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Artemisia, malaria, chlorogenic acid, diabetes

novembre 3, 2018

The concentration of caffeoylquinic (chlorogenic) acids is on the average 5-10 times higher than flavonoids in all Artemisia species. A Russian paper shows a strong inhibitory effect of the caffeoylquinic acids on α-glucosidase and α-amylase. These are digestive enzymes responsible for starch and carbohydrate cleaving them into smaller fragments, producing glucose in the final product. Plasmodium falciparum is feeding on glucose. If indeed the chlorogenic acids inhibit the glucose production in the human body they may have an influence on malaria. They will starve Plasmodium.

Boudelial A, Siracusa L, Henchiri C, Antidiabetic effects of aqueous infusions of Artemisia herba-alba. Planta Med. 2015 81, 696-704.

Along the same lines it was found that 2-deoxy glucose (2DG) prevented the development of cerebral malaria.

Wang A, Huen SC2. Glucose metabolism mediates disease tolerance in cerebral malaria. Proc Natl Acad Sci U S A. 2018 Oct 23;115(43):11042-11047. doi: 10.1073/pnas.1806376115..

Publicités

La Paramécie nous permettra-t-elle de comprendre le Plasmodium

septembre 28, 2018

De premiers essais en 2009 menés par IFBV-BELHERB avaient montré que la tisane Artemisia annua et la lumière UV tétanisaient les Paramécies dans l’eau. Ce protozoaire est souvent utilisé pour étudier la présence de substances chimiques dans les milieux aquatiques. Nous avons suggéré à une équipe de jeunes chercheurs katangais, Dr Jérôme Munya et Dr Constant Kansongo de reprendre ces expériences sur base du document en annexe pour voir si des essais sur Paramécie permettraient éventuellement de mieux comprendre l’action in vivo de certaines herbes médicinales sur le Plasmodium. Rappelons que les essais in vivo sur humains avec la tisane Artemisia annua sont interdits par l’OMS,.ce qui équivaut à une interdiction de la tisane, et de toutes autre herbe médicinale contre le Plasmodium. Les premiers résultats de Jérôme Munya réalisés à Paris montrent un effet quasi létal des infusions de Artemisia annua et Artemisia afra sur les Paramécies. Un énorme espoir donc pour mieux comprendre l’impact de ces tisanes et de leurs constituants sur le Plasmodium falciparum qui tue chaque année de 600 000 à 1 000 000 d’Africains. Cet engagement des jeunes Africains à trouver eux-mêmes des solutions à leurs problèmes nous enthousiasme. Pierre Lutgen

Malaria transmission vaccines fail, but Artemisia plants are very efficient

août 4, 2018

Vaccines blocking the invasion of malaria sporozoites failed so far, after 30 years of efforts, millions spent, and disastrous human clinical trials. The efforts and the millions are now focused on vaccines blocking transmission by gametocytes. The results are not yet encouraging but the updated Malaria Vaccine Technology Roadmap foresees that there will be a TBV vaccine available in 2030. The update was necessary as the program launched by WHO in 2000 ( TDR/RBM/MAL/VAC/2000.1) has not yet progressed very far.

Ogobara K. Doumbo, Karamoko Niaré, Sara A. Healy, Issaka Sagara and Patrick E. Duffy. Blocking Vaccines: Present Status and Future Perspectives. In Book: Towards Malaria Elimination – A leap forward 2018. Edited by Sylvie Manguin and Dr Vas Dev ISBN: 978-1-78923-551-7

Talaat KR, Ellis RD, Hurd J, Hentrich A, Gabriel E, Hynes NA, et al. (2016) Safety and Immunogenicity of Pfs25-EPA/Alhydrogel1, a Transmission Blocking Vaccine against Plasmodium falciparum: An Open Label Study in Malaria Naïve Adults. PLoS ONE 2016 11(10): e0163144. doi:10.1371/journal.pone.0163144

Ishino T, Tsuboi T. Progress toward a transmission-blocking vaccine against malaria. Lancet Infect Dis. 2018 Jul 27. pii: S1473-3099(18)30358-X. doi: 10.1016/S1473-3099(18)30358-X.

One may wonder why the authors of these recent papers do not mention the breathtaking transmission blocking results obtained with Artemisia plants in Africa.  These authors and research teams sponsored by Bigpharma are still on the laboratory bench and far from the community. Meanwhile a team of medical doctors in RDCongo, Jerome Munyangi and Michel Idumbo, have run randomized clinical trials on a large scale in the Maniema province with the participation of some 1000 malaria infected patients. The trials were run in conformity with the WHO procedures and compared Artemisia annua and Artemisia afra with ACTs (Coartem and ASAQ). For all the parameters tested herbal treatment was significantly better than ACTs: faster clearance for fever and parasitemia, absence of parasites on day 28 for 99.5% of the Artemisia treatments and 79.5% only for the ACT treatments…. The efficiency was equivalent for Artemisia annua and Artemisia afra. The results of this RDCongo team confirm previous results on the extraordinary prophylactic, suppressive and curative power of Artemisia plants

More important even is the observation for the total absence of gametocytes after 7 days treatment with the herb and that up to 28 days.

Pierre Lutgen.  Breaking news from clinical trials with Artemisia plants. http://www.malariaworld.org. January 5, 2016 

So far this document had 34830 readers. It was also published in a peer reviewed scientific journal.

Jérôme Munyangi, Pierre Lutgen, Lucile Cornet-Vernet, Artemisia plants, a deadly weapon against tropical diseases. Int J Clin Res Trials 2016, 1: 109. http://dx.doi.org/10.15344/ijcrt/2016/109

A tremendous hope for malaria eradication.

Palm wine and malaria

juillet 16, 2018

In a large scale clinical trial with malaria infected patients in RDCongo comparing ACTs with Artemisia infusion we observed a gender difference. Whilst both genders responded equally well to Artemisia, in the ACT-treated arm there was significantly more gametocyte carriage in females than males for days 14-28. Having no valid explanation for this observation, one may wonder if it due to differences in enzyme between males and females, like those which are responsible for a lower susceptibility of males to alcohol consumption. It is well known on the other hand that alcohol consumption, especially palm wine, is much higher for males than for females in tropical countries.
Jerome Munyangi; Lucile Cornet-Vernet, M.D.; Michel Idumbo; Chen Lu; Pierre Lutgen; Christian Perronne; Nadège Ngombe; Jacques Bianga; Bavon Mupenda; Paul Lalukala; Guy Mergeai; Dieudonné Mumba; Melissa Towler; Pamela Weathers. Artemisia annua and Artemisia afra tea infusions were equal to or better than artesunate-amodiaquine (ACT) in treating Plasmodium falciparum malaria in a large scale, double blind, randomized clinical trial. Submitted to Phytomedicine for publication Jan 2018
Chrostek L, Jelski W, Szmitkowski M, Puchalski Z. Gender-related differences in hepatic activity of alcohol dehydrogenase isoenzymes and aldehyde dehydrogenase in humans. J Clin Lab Anal. 2003;17(3):93-6.
During gametocytogenenesis malaria parasites hide in the bone marrow. Ethanol has an effect on bone marrow. Biopsies from 30 alcohol-dependent individuals were investigated. The findings took the form of heightened ineffective erythropoiesis in bone marrow associated with impaired iron utilization. Both may be detrimental to the survival of the gametocytes.
Michot F, Gut J. Alcohol-induced bone marrow damage. A bone marrow study in alcohol-dependent individuals. Acta Haematol. 1987;78(4):252-7.
The effect of ethanol on the in vitro growth of the malaria parasite Plasmodium falciparum was investigated during six days of incubation. A significant growth inhibition for ethanol concentrations was observed on each day. Malarial parasites are strongly inhibited by ethanol concentrations.
Lell B, Binh VQ, Kremsner PG. Effect of alcohol on growth of Plasmodium falciparum. Wien Klin Wochenschr. 2000 May 19;112(10):451-2.
N.F. Milan et al., Alcohol consumption as self-medication against blood-borne parasites in the fruit fly, Current Biology, 2012.01.04, 2012.
Fever is accompanied by glycogen destruction. This was already discovered more than 100 years ago. Glycogen disappears from the liver during tetanus, diphteria and pneumonia. A natural way of our body to fight parasites and diseases. It makes thus complete nonsense to fight fever in the early stages of a malaria infection.
G Graham EP Poulton. The Influence of High Temperature on Protein Metabolism with reference to Fever, Inter. Journal of Medicine, Volume os6, Issue 1, 1 October 1912, Pages 82–124.
Colla A, Archiv Ital de Biologie, 1896, XXVI, p120
Alcohol also removes glycogen from the liver.
W Salant. The Influence of Alcohol on the Metabolism of Hepatic Glycogen. Proceedings of the Society for Experimental Biology and Medicine, 1905, iii, p 58.
Chronic ethanol consumption also results in a dramatic decrease in liver glycogen concentrations, which could be related to either a depressed rate of synthesis or an increased rate of breakdown.
Van Horn CG, Ivester P, Cunningham CC. Chronic ethanol consumption and liver glycogen synthesis. Arch Biochem Biophys. 2001 Aug 1;392(1):145-52.
Macrophages, including Kuppfer cells, appear to increase their production of cytokines in patients with alcoholic liver disease. Precursors of macrophages, i.e. monocytes with alcohol induced hepatitis produce greater amounts of TNF-α and reactive oxygen species. These data have been confirmed in animals. Malaria parasites are destroyed by oxidative species, like NO, H₂O₂ or artemisinin peroxides.
Wheeler MD, Endotoxin and Kupffer cell activation in alcoholic liver disease. Alcohol Res Health. 2003;27(4):300-6.
Honchel R, Ray MB, Marsano L, Cohen D, Lee E, Shedlofsky S, McClain CJ. Tumor necrosis factor in alcohol enhanced endotoxin liver injury. Alcohol Clin Exp Res. 1992 Aug;16(4):665-9.
Sheth NK, Wisniewski TR, Franson TR Survival of enteric pathogens in common beverages: an in vitro study. Am J Gastroenterol. 1988 Jun;83(6):658-60.
Wine is efficient against other pathogens. An in vitro study was undertaken to determine the potential for survival of enteric pathogens in common drinking beverages. Three carbonated soft drinks, two alcoholic beverages, skim milk, and water were inoculated with Salmonella, Shigella, and enterotoxigenic Escherichia coli, and quantitative counts were performed over 2 days. The study showed poorest survival of all three organisms in wine, and greatest growth in milk and water.
Long-term intake of alcohol affects the immune system. Serum levels of immunoglobulins (total IgE, IgG, IgM, and IgA) therefore, were analyzed in adult chronic alcoholics in Indian population and were correlated with different epidemiological and alcohol-related parameters. The results showed that 98% of alcoholics had abnormal immunoglobulin levels and 92% showed high or very high total serum IgE levels compared to 24% of the control group. Several other studies have shown that that total serum IgE concentrations are increased in moderate alcohol consumers with respect to abstainers. This increase is independent of cofounders such as age, sex, liver disease, cigarette smoking,
Yashwant Kumar, Lakshmi PVM, Ranjana Walker Minz, Evaluation of Serum Immunoglobulins IgG, IgA, IgM and Total IgE in Chronic Alcoholics: A Community-based Study. Immunochemistry & Immunopathology. 2015, 1,1, 1000102
Lomholt FK, Nielsen SF, Nordestgaard BG. High alcohol consumption causes high IgE levels but not high risk of allergic disease, J Allergy Clin Immunol. 2016 Nov;138(5):1404-1413.e13. doi: 10.1016/j.jaci.2016.05.022.
C Vidal. Influence of alcohol consumption on serum IgE levels. Alcohol Clin Exp Research. 2002, 26, 59-64
A Gonzalez-Quintela, C Vidal, ++Alcohol-induced alterations in serum immunoglobulin IgE levels in human subjects Front bioscop 2002, 1:7, 234-44
In a recent paper we have shown how IgE contributes to malaria prophylaxis.
Pierre Lutgen, Antibodies, Prophylaxis, Transmission. Pharm Pharmacol Int J 2018, 6(2): 00155
Alcohol can increase the solubility of poorly soluble drugs and hence increase their bioavailability. And increases the intestinal permeability to indigested macromolecules.
Jonas H. Fagerberg, Erik Sjögren, Christel A.S. Bergström. Concomitant intake of alcohol may increase the absorption of poorly soluble drugs. European Journal of Pharmaceutical Sciences. Volume 67, 25 January 2015, Pages 12-20
Worthington BS, Meserole L, Syrotuck JA. Effect of daily ethanol ingestion on intestinal permeability to macromolecules. Am J Dig Dis. 1978 Jan;23(1):23-32.
Palm wines
A study from Niger showed that palm wine consumption may deplete the body’s antioxidants against free radical attacks and render the body in a state of oxidative stress.
Ogunro PS, Ologunagba PO. The effect of palm wine on lipid peroxidation and antioxidant status of rural dwellers in South West Nigeria. Niger Postgrad Med J. 2011 Sep;18(3):186-90.
In Nigeria a face-to-face ethno-medical survey on 1000 randomly selected families in confirmed the use of palm wines as antimicrobial agents and prophylactic agents against malaria. The hypothesized mechanism is that the ethanol content of the palm wines may increase membrane fluidity, altering ion channels and K⁺ content of the infected erythrocytes thereby impairing motor performance of Plasmodia.
Ibegbulem CO, Alisi CS, Medicinal values of Elaeis guineensis and Raphia hookeri wines. Journal of Research in Biology 2012, 2, 6, 589-595
Chi LM, Wu WG, Mechanism of hemolysis of red blood cell mediated by ethanol. Biochimica and Biophysica Acta 1991, 1062, 46-50
Medicinal herbs can be infused in palm wine. Palm wine is added to the decoctions of bitter herbs to increase their palatability.
Palm wine is very rich in potassium, sodium is only present in traces, a situation very similar to that of Artemisia annua.
Chukwujindu M A Iwegbue, A survey of metal profiles in some traditional alcoholic beverages in Nigeria. Food Sci Nutr. 2014 Nov; 2(6): 724–733.
Many palmwines are rich in anthocyanins concentrated in the pericarp. Anthocyanins have a strong effect on hemozoin inhibition like in black or red grapes or in pomegranate (Mutaz Akkawi , personal communication).
Rajinder Singh, Eng-Ti L. R Sambanthamurthi The oil palm VIRESCENS gene controls fruit colour . Nature Communications 2014, volume 5, Article number: 4106
Mutaz Akkawi, Saleh Abu-Lafi, Qassem Abu-Remeleh, Marah Kiswani, Mutaz Qutob, Sameh Nusseibeh, Pierre Lutgen. HPLC separation of phenolic phytochemicals from grape peels and seeds water extracts and their invitro antimalarial activities. Pharm Pharmacol. Int. J. Volume 6 Issue 4 – 2018

Conclusion
It is hard to outline a conclusion. Heavy alcohol drinking certainly never should be recommended. Alcoholism is a health problem. Lets rather listen to the French” Boire du vin rouge modérément est bon pour la santé”.
Pierre Lutgen

Dried Artemisia is stable after ageing

juillet 15, 2018

In 2001 WHO posted a statement on their home page, without signatures, without references: « Due to the instability of artemisinin in raw materials of Artemisia annua L, the leaves need to be stored in cool conditions — preferably below 20°C. Most malaria endemic countries have warm climates and people generally lack access to refrigeration, so it is difficult for patients to keep artemisinin-containing tea bags under 20°C in their homes” A statement not substantiated by scientific papers. Cui bono?

Our associations immediately gathered available data which prove the contrary

– The analysis done by Rosine Chougouo at the LNS at Luxembourg on 3 year old samples

– The data from Fr VanderKooy

– The data from the VUB for samples stored > 3 years

– The thesis of Ivanescu in Romania.

– The data from Pamela Weathers, Worcester Polytech Institute.

Scattered data of course, but which gave us good confidence. We than discovered an important paper from South Africa which shows that Artemisia afra improves with age in 16 years of dry storage.

Stephen O Amoo, Adeyemi O Aremu. Antioxidant and acetylcholinesterase-inhibitory properties of long-term storedmedicinal plants. BMC Complementary and Alternative Medicine 2012, 12:87 doi:10.1186/1472-6882-12-87

The instability is rather a problem of ACTs, artesunate and other antimalarials as demonstrated in the scientif literrature.

S Houzé, A Munier. Shelflife of Predosed Plates containing Mefloquine, Artemisinine, Artesunate. J. Clin. Microb 2007, 4, 8. 2734-36

Malaria and silica particles

juin 5, 2018

Chronic inhalation of crystalline silica is an occupational hazard that results in silicosis due to the toxicity of silica particles to lung cells
It is thus surprising to read that silica nanoparticles are extensively applied for drug delivery Silica particles are used as conveyors of drugs with low bioavailability. Even for artemether.
Jaywant N.Pawara Harita R.Desaia Kailas Exploring the potential of porous silicas as a carrier system for dissolution rate enhancement of artemether. Asian Journal of Pharmaceutical Sciences 2016. 11, 760-770
Silica nanoparticles have the advantage of a high specific surface area and can therefore guest a considerable amount of drug. Silica may enhance in some cases the vaccination efficiency. In vitro internalization of silica particles has also been described to stimulate macrophages to release inflammation promoting mediators.
Silica and immunoglobulins E
Silica may boost the immune system and stimulate IgE production. This effect is known since 40 years. IgE is probably the most important item in acquired humoral activity against malaria.
Pierre Lutgen. Antibodies, prophylaxis, transmission. Pharmacy & Pharmacology International Journal. Published Feb 2018.
O Aminian, O Giahi, Humoral immune system alterations in silica exposed workers. Iranian Journal Public Health, 2008, 37, 142-145
D Massé, C Voisine. Increased vaccination efficiency with apoptotic cells by silica-induced, dendritic-like cells. Cancer Research . 2002 Feb 15;62(4):1050-6.
Mancino D, Buono G, Cusano M, Minucci M. Adjuvant effects of a crystalline silica on IgE and IgG1 antibody production in mice and their prevention by the macrophage stabilizer poly-2-vinylpyridine N-oxide. Int Arch Allergy Appl Immunol. 1983;71(3):279-81.
Mancino D. and Bevilacqua N. Persistent and boosterable IgE antibody production in mice injected with low doses of ovalbumin and silica. Int Arch. Allergy Appl. Immunol. 57:155, 1978
Nermin Zawilla, Fatma Taha, and Yasser Ibrahim. Liver functions in silica-exposed workers in Egypt: possible role of matrix remodeling and immunological factors. Int J Occup Environ Health. 2014 Apr; 20(2): 146–156.
A single dose of standard quartz with particle size <5μm is able to stimulate in Balb/c mice the production of IgE and IgG1 antibody.
Mancino D, Buono G, Minucci M. Adjuvant effects of crystalline silica on IgE and IgG1 andibody production in mice. Int Arch Allergy Immunol 1983, 71, 279-281
Silica in plants and in Artemisia
This mineral has barely been studied in plants. Plants take up silicon as mono-silicic acid and later it is deposited in its polymerized form as amorphous hydrated silica. Major silica depositions occur in root endodermis, leaf epidermal cells and trichomes.
The ability of a plant to accumulate Si varies greatly between species. It is up to 2% in wheat, rice, oats, close to 0 % in flowers, and intermediate in kitchen and medicinal herbs: 0.4 % in spinach, 0,1 in ginseng, 0.32%, in parsley, 0.56 in salvia, 0,56 in tilia, 0.26 % in dill, 0,67 in inula, 0,6 in hibiscus, 0.61% in mint, 0.35% in Artemisia annua, 0,22% in Artemisia absinthium, 0,57%, in Artemisia frigida, but only 0.002% in Artemisia maritima. Horsetail (Equisetum arvense) and nettle (Urtica dioica) containing 1.1% silica were used in Europe against malaria
Giuseppe Tagarelli, Antonio Tagarelli. Folk medicine used to heal malaria in Calabria (southern Italy). J Ethnobiol Ethnomed. 2010; 6: 27.
MJ Hodson, PJ White. Phylogenetic variation in the silicon composition of plants, Annals of Botany, 2005, 96, 1027-1046
Heather A. Currie and Carole C. Perry.. Silica in Plants: Biological, Biochemical and Chemical Studies. Ann Bot. 2007 Dec; 100(7): 1383–1389.
A Smis, F Ancin. Determination of plant silicon content with near IR reflectance spectrocopy. Frontiers in Plant Science, 22014,5. 496.
Rahimi Rahmatollah and Rabani Mahbobeh. Mineral contents of some plants used in Iran. Pharmacognosy Res. 2010 Jul-Aug; 2(4): 267–270
In many plants silica is present in the form of phytoliths in cell walls for their strenghtening. Families with high phytolith production are Acanthaceae, Aceraceae, Annonaceae, Asteraceae, Artemisia tridentata and Artemisia spicata for example contain phytoliths.
Mikhail Blinnikov. Phytoliths in plants and soils of the interior Pacific Northwest, US Review of Paleobotany and Palynology 2005 135 , 71 -98
Phytoliths are present in the glandular trichomes of the plants. Trichomes are fine outgrowths or appendages on plants. Trichomes serve as the plant’s phalanx of little shields responsible for the developing protection against fungus and insects.
Cristina Rostkowska, Caroline M. Mota,Taísa C. Oliveira, Si-Accumulation In Artemisia annua Glandular Trichomes Increases Artemisinin Concentration, but Does Not Interfere In the Impairment of Toxoplasma gondii Growth. Front Plant Science, 2016, 7, 1430.
The presence of trichomes is ubiquitous in the genus Artemisia. 15 taxa were examined to this effect to be used as taxonomic markers.
M Q Hayat, M Ashraf, Diversity of foliar trichomes and their systematic implications in the genus Artemisia. Int J Agriculture & Biology, 2009, 11 : 542-546
Food products have been shown to contain silica in the nanometer size range (i.e. 5 – 200 nm). Rats orally exposed to silica nanoparticles saw a 1.5 to 2 times increase of the silica content in lung, kidney, liver, brain, testis, spleen but no clear target organ could be identified after 28 days of exposure. The trial showed accumulative properties, and the particles were retained in liver and spleen for at least 4 weeks.
M van der Zande, R Vandebriel, Sub-chronic toxicity study in rats orally exposed to nanostructured silica. Particle and Fibre Toxicology, 2014, 11 :8
Bioavailability of silica particles does not depend on particle size. The bioavailability of nanoparticles versus their bulk counterparts was evaluated in rats after a single oral administration and intravenous injection, respectively. The results demonstrated that all bulk materials had slightly higher crystallinity than nanoparticles, however, their dissolution properties were not affected by particle size. No significant difference in oral absorption and bioavailability was found between nano- and bulk-sized materials. Silica particles are retained for over 30 days in the tissues because of the endocytosis by macrophages,
Kim MK, et al. Bioavailability of Silica, Titanium Dioxide, and Zinc Oxide Nanoparticles in Rats.J Nanosci Nanotechnol. 2016. PMID 2742775
African diet is rich in cereals and starch, loaded in silicium, even bananas, thus promoting IgE build-up. European food contains more vegetables, fruits, milk products, meat, very poor in silicium.

Silica, sporozoites and Kupffer cells
Since several decades it is suspected that Kupffer cells have a supportive role in the homing of sporozoites. Macrophages were thought to act as a barrier to sporozoite entry in liver cells. Evidence is gathering for a possible dual role of macrophages under different sets of conditions. Before activation macrophages might act as transporting agents of sporozoites to the parenchymal cells of the liver. It is now recognized that Kupffer cells function as portals for malaria sporozoites to the liver. They are the resident macrophages of the liver and should phagocytose sporozoites. These traverse Kupffer cells, yet suffer no harm. It seems plausible that Plasmodium evolution produced sporozoites with the ability to manipulate Kupffer cell function. They have learned to use Kupffer cells as an affable portal and hepatocytes as a relatively secure niche and nutritional “Schlaraffenland” (land of plenty), thereby providing a jump start towards a successful blood infection.
Vreden SG, The role of Kupffer cells in the clearance of malaria sporozoites from the circulation. Parasitol Today 1994, 10, 304-8
Klotz C, Plasmodium yoelii sporozoites modulate cytokine profile and induce apoptosis in murine Kupffer cells. Int J Parasitol. 2008.
It was already recognized 30 years ago that silica particles might strongly affect sporozoite uptake in the liver. A reduction in Kupffer cell number and activity, induced by silica treatment, resulted in a very significant decline in uptake of infective sporozoites Plasmodium yoelii nigeriensis by the perfused liver–and a parallel fall in the successful infection of the host by inoculated sporozoites in vivo. Silica treatment produced no significant detectable pathological changes in hepatocytes. Light microscopy revealed some focal degeneration in the blood vessels of silica-treated animals, but the sinusoids remained unaffected except that the numbers of Kupffer cells were markedly reduced. Scanning electron microscopy confirmed that the silica treatment had little effect on the structure of the capillaries and sinusoids. This evidence suggests that the silica pretreatment reduces the phagocytic properties of liver by specifically removing Kupffer cells. The-uptake of sporozoites is significantly reduced in silica-treated livers with 59 % of the original sporozoite load disappearing after 15 min perfusion.
Sinden RE, Smith JE. The role of the Kupffer cell in the infection of rodents by sporozoites of Plasmodium: uptake of sporozoites by perfused liver and the establishment of infection in vivo. Acta Trop. 1982 Mar;39(1):11-27.
Macrophages internalize silica. Exposure of cultured macrophages to crystalline silica leads to cell death; however, the mechanism of cell–particle interaction, the fate of particles, and the cause of death are unknown. Eighty percent of macrophages die within 12 hours of silica exposure. Latex beads of the same size are also phagocyted rapidly but do not lead to macrophage death. Macrophages gather particles by extending protrusions. These draw the particles to the cell body where they stick avidly.

Renée M. Gilberti, Gaurav N. Joshi, The Phagocytosis of Crystalline Silica Particles by Macrophages. Am J Respir Cell Mol Biol. 2008 Nov; 39(5): 619–627.

Kupffer cells stimulated by silica nanoparticles release large amounts of reactive oxygen species, tumor necrosis factor-α and nitric oxide. Silica particles also increase production of interleukin-6. This oxidative and inflammatory burst is evidently detrimental for sporozoites.
Chen Q, Xue Y, Sun J. Kupffer cell-mediated hepatic injury induced by silica nanoparticles in vitro and in vivo. Int J Nanomedicine. 2013;8:1129-40. doi: 10.2147/IJN.S42242. Epub 2013 Mar 15
C. Allison, J. S. Harington, and M. Birbeck. An examination of the cytotoxic effects of silica on macrophages. J Exp Med. 1966 Aug 1; 124(2): 141–154.
Rocha-Parise M, et al. Lymphocyte activation in silica-exposed workers. Int J Hyg Environ Health. 2014 Apr-May.
Silica particles also adsorb hydrogen peroxide and other peroxides present in Artemisia and its infusion, These stabilized peroxides progressively attack Kupffer cells.
D Lewandowski, D Bajerlein, Adsorption of hydrogen peroxide on functionalized mesoporous silica surfaces. Structural Chemistry, 2014, 25, 1505-1512.
Silica treated mice were challenged with Plasmodium berghei. A dose up to 5 mg per mouse before challenge resulted in protection of the animal. No mortality was recorded in mice which received silica alone (35 mg; 5 mg/day x 7 days). Death due to lethal P.berghei infection could be delayed or prevented by altering/reducing the functional activities of macrophages during the course of infection.
Pillai CR, Devi CU, Choudhury DS, Singh NN. Role of macrophages in experimental malaria: IV–Bioassay of silica in immunity against Plasmodium berghei infection. Indian J Exp Biol. 1997 Aug;35(8):861-5.
Before recommending the administration of silica against malaria caution however is recommended. As described previously silica particles affect the population and functionality of macrophages. And this may have a detrimental effect on the resistance against other infections. It was shown for example that the inoculation of silica a few days before infecting mice intraperitoneally with Salmonella typhimurium severely reduced the survival of these mice.
A O’Brien, I Scher, S Formal. Effect of silica on the innate resistance of inbred mice to Salmonella typhimurium infection. Infection and Immunity. 1979, 25, 513-520.

Interaction of silica particles with erythrocytes

Incubation of erythrocytes with silica nanoparticles caused a dose-dependent hemolytic effect. Transmission electron microscopy analysis revealed that the particles are taken up by erythrocytes. Lipid erythrocyte susceptibility to in vitro peroxidation measured by malondialdehyde showed a significant and dose-dependent increase.
Nemmar A, et al. Interaction of amorphous silica nanoparticles with erythrocytes in vitro: role of oxidative stress. Cell Physiol Biochem. 2014.
H E Kettiger, Silica nanoparticles and their interaction with cells: a multidisciplinary approach. PhD Thesis, Basel 2014

The influence of five varieties of silica dust on lipid peroxidation in erythrocytes was studied in vitro. All the varieties of silica dust investigated induced a significantly higher level of lipid peroxides than was found in the control samples. The hemolysis produced by silica dusts was associated with the formation of an appreciable amount of malonaldehyde, indicating peroxidative cleavage of the polyunsaturated fatty acids. The results obtained suggest that lipid peroxidation of membrane-bound polyunsaturated fatty acids may be involved in the cytotoxic activity of SiO2 dust.

Silvia Gabor, Zoe Anca. Effect of silica on lipid peroxidation in the red cells. Internationales Archiv für Arbeitsmedizin. January 1974, Volume 32, Issue 4, pp 327–332

Slawson V, Adamson AW, Mead JF. Autoxidation of polyunsaturated fatty esters on silica. Lipids. 1973 Mar;8(3):129-34.
Silica particles also have an effect on erythrocyte morphology. They become swollen and take irregular shapes and even fragment.
L. Jiang, Y Yu, Oxidative damage and energy metabolism disorder contribute to the hemolytic effect of amorphous silica nanoparticles. Nanoscale Research Letters, 2016 11 :57
The authors of this paper conclude that amorphous silica nanoparticles cause dose-dependent hemolytic effects and remarkably alter the shape and deformability of erythrocytes. The abilities of ·OH elimination is inhibited to facilitate ROS accumulation in erythrocytes. Silica nanoparticles induce a dose-dependent ROS production, leading to oxidative damage of erythrocyte membrane by increasing the lipid peroxidation and decreasing the antioxidant ability, consequently causing hemolysis. ATPase activities are inhibited, and the energy metabolism disorder of membrane contributes to the hemolytic effects in human erythrocytes.
In vitro studies studies on the destruction (lysis) of red blood cells by some silicate minerals showed the reaction to be complete in less than one hour and very destructive to the cell membrane. Surprisingly, the activity of silica was stronger for silica than for chrisotyle (asbestos). Aluminium oxide and hydroxide did not show this hemolytic effect.
DW Oscarson, JL Ahlrichs, Lysis of erytrocytes by silicate mineerals Clays and Clay Minerals, 1986, 34, 74-80.
M Waldecker, A Dasanna, M Lanzer. Differential time-dependent volumetric and surface area changes and delayed induction of new permeation pathways in P falciparum infected erythrocytes. Cellular Microbiology, 2012. 19 :e12650
The human malaria parasite Plasmodium falciparum drastically changes the volume and morphological properties of the host cell. Malaria-infected erythrocytes are characterized by a complex ultrastructure with knobs, caveolae and clefts. This is an open door for silica entrance, further increasing the osmotic pressure, and provoking bursting of the erythrocyte before the schizont-trophozoites maturation is completed.
The action of silica particles on erythrocytes may be similar to the toxicity they have on bacteria. Athors of a recent study have demonstrated the bactericidal effect of these nanoparticles to both susceptible and even multiple resistant E. coli, in which the free-antibiotic could not efficiently kill the bacteria. This occurs because the nanoparticle itself can also kill the bacteria
Larissa Brentano Capeletti, Luciane França de Oliveira, Kaliandra de Almeida Gonçalves, Jessica Fernanda Affonso de Oliveira, Ângela Saito, Jörg Kobarg, João Henrique Zimnoch dos Santos, and Mateus Borba Cardoso. “Tailored Silica–Antibiotic Nanoparticles: Overcoming Bacterial Resistance with Low Cytotoxicity”, Langmuir, 2014, 30 (25), pp 7456–7464. DOI: 10.1021/la4046435
Silica particles and CYP3A4
Because silica nanoparticles are used in food and drugs, their effects on metabolic enzymes such as cytochrome P450s (CYPs) are of particular interest. Xenobiotics such as drugs are metabolized by CYPs which are expressed at the highest levels in the liver. Cytochrome P450 3A4 (CYP3A4) is involved in the metabolism of approximately half of the drugs in use. Drugs, some foods and beverages affect the activity of CYPs. For example grapefruit juice inhibits CYP3A4 activity and thus can lead to side effects when taken with drugs metabolized by CYP3A4. In contrast, St. John’s wort induces CYP3A4 and thus reduces the efficacy of some drugs that undergo CYP3A4-dependent metabolism.
Nanomaterials have also been reported to affect CYP3A4 activity. The small size and high surface area of nanomaterials give them useful properties such as unique chemical reactivity ; therefore, silica nanoparticles have the opportunity to react with CYPs.
Some recent work from Japan clearly shows that silica nanoparticles inhibit CYP3A4, again more than ketoconazol, the strongest inhibitor known.
Shunji Imai, Yasuo Yoshioka, Yuki Morishita Size and surface modification of amorphous silica particles determine their effects on the activity of human CYP3A4 in vitro. Nanoscale Res Lett. 2014; 9(1): 651.
Beatrice Camarota, Sonia Fiorilli. Immobilization of CYP3A4 Enzyme onto SBA-15-like Mesoporous Silica and Porous Silicon Matrices. Politecnico di Torino, C.so Duca degli Abruzzi 24, Turin, Italy
Previously Japanese authors had shown that silica nanoparticles may drastically enhance the efficacy or toxicity of chemicals
Nishimori H, Kondoh M, Isoda K, Influence of 70 nm silica particles in mice with cisplatin or paraquat-induced toxicity. Pharmazie. 2009 Jun;64(6):395-7.
Li X, Kondoh M, Watari A, Hasezaki T, Effect of 70-nm silica particles on the toxicity of acetaminophen, tetracycline, trazodone, and 5-aminosalicylic acid in mice. Pharmazie. 2011 Apr;66(4):282-6.
Artemisia plants are known for their strong CYP3A4 and CYP 2B6 inhibition activities. In a pionneering study in 2010, the University of Louvain had studied the anti-inflammatory effect and modulation of cytochrome P450 activities by Artemisia annua tea infusions in human intestinal Caco-2 cells
Melillo de Magalhães, Yves-Jacques Schneider. Anti-inflammatory effect and modulation of cytochrome P450 activities by Artemisia annua tea infusions in human intestinal Caco-2 cell Food Chemistry 134(2):864-71 · September 2012
These assays were done on aqueous infusionsof Artemisia annua samples from 7 different origins. For all samples there was a significant reduction in the CYP3A4 activity with the highest reduction down to 37% of the control value for the sample from Luxembourg (registration number MNHNL17732 at the herbarium of Luxembourg). Ketoconazole, a well-known specific and potent CYP3A4 inhibitor used for comparison at 50 µM, completely inhibited the CYP3A4 activity. Artemisinin, rosmarinic and chlorogenic acids tested at plausible intestinal concentrations had no effect on the CYP3A4 activity.
More recently similar assays were run at the Vrije Universiteit Brussel. They used ethanolic extracts 32 gr dried leaves of Artemisia plant material extracted by Soxhlet in 1 litre ethanol. They worked with Artemisia plants from different origins, including the species Artemisia abrotanum, Artemisia apiacea, Artemisia pontica, Artemisia herba alba, Artemisia absintium, Artemisia afra. The CYP3A4 inhibition was surprisingly high for all Artemisia samples, up to 6 times higher the for ketoconazol (0.11 µg/mL) or for diluted grapefruit juice. This is surprising because grapefruit juice has the reputation to be the strongest CYP3A4 inhibitor from plant origin. Surprising is also the fact that all Artemisia samples show CYP3A4 inhibition, except one.
Lazaridi Kristina. Invloed van de chemische samenstelling van Artemisia annua op CYP3A4-activiteit en antioxidant vermogen. Masterproef VUB, 2014
This is confirmed by a recent study from Egypt on the extracts of 57 medicinal plants. Generally aqueous extracts have a stronger effect than ethanolic extracts. Among all these plants, for a concentration of 100 µg/ml, Artemisia annua and Artemisia capillaris are ranking at the top with a few others with an inhibition of 83.96 and 82,36 % respectively. No difference thus between the two species, indicating that artemisinin plays no role.
ML Ashour, F Youssef, H Gad, M Wink, Inhibition of CYP3A4 activity by extracts from 57 plants used in TCM. Pharmacognosy Magazine, 2017, 13 :300-8s.
In search of a conclusion
It has been demonstrated elsewhere that high IgE levels strongly decrease the gametocyte concentration
Pierre Lutgen, Antibodies, Prophylaxis, Transmission. Pharm Pharmacol Int J 2018, 6(2): 00155
R Lawaly, L Konate, R Paul. Impact of mosquito bites on gametocyte prevalence in asymptomatic chronic Plasmodium falciparum infections and correlations with IgE and IgG titers. Infection and Immunity, 2012, 80, 2240-46
If silica particles truly have such a dramatic effect on sporozoite invasion, on drug efficacy, on infected erythrocytes and on gametocytes one may wonder why all the laboratories desperately looking for a solution to the alarming malaria catastrophy ignored this possibility. Maybe because all studies are based on in vitro efficiencies of potential antimalarials against parasites. Silica particles have no direct toxic effect on sporozoites, merozoites, trophozoites, gamatocytes, at least no scientific paper describes a similar effect. These particles like other nanoclay particles don’t have a toxic effect on Paramecium caudatum either.
M Kryuchkova, A Danilushkina, Y Lvov, Evaluation of toxicity of nanoclays in vivo : a Paramecium caudatum study. Environ Sci Nano, 2016, 3, 442-452
Maybe because most of the studies are based on extracts obtained with organic solvents, and this approach ignores minerals and hydrophilic substances.
Maybe Bigpharma is looking desperately for new organic molecules for new antimalarial monotherapies and silica particles are difficult to sell with a sizeable profit margin.

MIM Dakar 2018 ignores African pionneering research on Artemisia

avril 30, 2018

MIM was established in 1997 with a mission to strengthen the capacity of malaria-endemic countries in Africa to carry out research that is required to develop and improve tools for malaria control.
It is thus surprising that none of the recent clinical trials carried out in several African countries by African doctors and universities, with Artemisia plants, which not only give cure rates close to 100%, eliminate gametocytes and transmission but also show stronger prophylactic properties than current antimalarial vaccines, that none of these be presented and discussed at the Dakar conference.

Immunoglobulins and malaria prophylaxis

février 11, 2018

Immunoglobulins and malaria prophylaxis

Elevated levels of immunoglobulin IgE are found in many infections and allergies. IgE is increased in the majority of individuals living in areas of high malaria endemicity. Plasmodium can give rise to IgE in the absence of other pathogens, such as helminths which also are known to induce IgE elevation. IgE in association with monocytes or platelets may give rise to reactions that are protective and/or pathogenic. Most children and adults living in areas where the endemicity of Plasmodium falciparum malaria is high, have significantly elevated levels of both total IgE antibodies and specific antimalarial IgE bodies in blood. IgE containing immune complexes are known to give rise to monocyte activation via the NO transduction pathway. A recent study in Nigeria shows that the malaria infection specifically raises IgE, but that IgG and IgM remain virtually stable. There is a strong positive correlation between IgE and parasite density. IgE raises almost exponentially with the severity of the disease. The increase is the same for males and females as has been shown in several studies.
P Perlmann, M Aikawa. Contrasting functions of IgG and IgE antimalarial antibodies in uncomplicated and severe Plasmodium falciparum malaria. Am J TropMed Hyg, 2000, 62, 373-377.
Eze Evelyn Mgbeoma, C Serekara. Immunoglobulin levels in Plasmodium falciparum malaria infected subjects in Port Harcourt, Nigeria. Int J Adv Multidipl Res, 2016. 3, 49-55
SGO Johansson, Immunological levels in Ethiopian preschool children with special reference to high concentrations of IgE. The Lancet, 1968 291, 1118-1121
J Seka-Seka, Y Brouth. The role of serum immunoglobulin E in the pathogenesis of Plasmodium falciparum malaria in Ivorian children. Scandinavian J of Immunol, 2004, 59, 228-230.
C Calissano, D Modiano, B Sodiomon, IgE antibodies to Plasmodium falciparum and severity of malaria in children of one ethnic group living in Burkina Faso. Am J Trop Med Hyg, 2003, 69, 31-35
IgE elevations are the expression of CD4+ cells and we have been able to demonstrate that these are increased by the administration of Artemisia annua and Artemisia afra. CD4+ cells are already induced in the pre-erythrocytic stages of malaria. This leads to a wide range of antibodies including some specific against the circumsporozoite protein (CSP).
Constant Kansango Tchandema, Pierre Lutgen. In vivo trials on the therapeutic effects of encapsulated Artemisia annua and Artemisia afra. Global Journal for Research analysis 2016, 6, 228-234
D Perez-Mazliah, J Langhorne. CD4 T-cell subsets in malaria revisited: Frontiers in Immunology, 2015,5, article 671.
The elevation of specific Plasmodium falciparum antibodies is age dependent. The prolonged and repeated exposure to malaria parasites is necessary for the induction of these specific antibodies and there is a significant correlation between their level and the number of malaria attacks.
Srisin Khusmith, J Panitchakorn. IgE Elevation and anti-Plasmodium falciparum IgE antibodies: association of high level with malaria resistance. Southeast Asian J trop Med Public Health 2001, 32, 4, 696-702
The ability to resist Plasmodium falciparum malaria is an important adaptive trait of human populations living in endemic areas. The detection of significant differences in the expression of this trait and the identification of the factors involved should improve the understanding of the host-parasite relationship and might lead to advances in control strategies. In a study in Tanzania it was clearly demonstrated that high anti-Plasmodium falciparum IgE levels were associated with reduced acute risk of acute malaria in all age groups, independently of the total IgE level. High levels of IgG weren’t associated eiher with a reduced risk to succumb to a new clinical episode.
Bereczky S, Montgomery SM. Elevated anti-malarial IgE in asymptomatic individuals is associated with reduced risk for subsequent clinical malaria. Int J Parasitol. 2004 Jul;34(8):935-42.
Reactions to mosquito bites, being immunological in nature, lead to swelling, wheal and flare of the skin. They are due to the mosquito salivary proteins. Mosquito saliva contains many biological materials, anticlotting and antiplatelet factors and vasodilators which presumably increase the speed sat which blood from the host is imbibed. But also immunomodulators, allergens which bind to IgE and induce histamine release. Sporozoites express α-gal (galactose-alpha-1,3-galactose), and the bite of mosquitoes like the bite of ticks may lead to an overload with immunoglobulin E antibodies. The molecule α-gal is also present on Trypanosoma and Leishmania parasites.
Avila JL, Rojas M, Immunogenic Gal alpha 1 eptopes are present on pathogenic American Trypanosoma and Leishmania. J Immunol 1989, 142, 2028-2834
Peng Z, Simons FE, Cross-reactivity of skin and serum specific IgE responses and allergen analysis for three mosquito species with worldwide distribution. J Allergy Clin Immunol, 1997, 100, 192-8.
Allergens are present in the saliva of most of the mosquitoes, even those which are not infected. A study has shown in a murine model that bites from uninfected mosquitoes prior to Plasmodium yoelii infection influences the local and systemic immune responses and limits parasite development within the host. The difference in liver parasite burdens becomes evident at 20 hours post infection. Another strange way to achieve vaccination! And it may explain why people living in countries with dense Anopheles populations are immunized by these bites. And even if regular consumption of Artemisia infusion or vaccines have a prophylactic action the IgE related immunity does not decrease because people are continuously biten by mosquitoes with the concommittant injection of saliva. Although most of these people are asymptomatic, they do not develop high levels of parasitemia and fever because the saliva of the mosquitoes maintains a high level of IgE.
There are also seasonal increases in IgE, after the rainy season. They are absent or low in the absence of bites
Palosuoa K, Reunula T. Seasonal increase in human IgE and IgG4 antisaliva antibodies to Aedes mosquito bites. Int Arch Allergy Immunol 1997 114, 367-72
F Remoue, E Alix, IgE and IgG4 antibody responses to Aedes saliva in African children. Acta Tropica, 2007, 108-115
Although the mechanism has yet to be completely elucidated, a similar phenomenon has been noticed: repeated infestation with Ixodes scapularis ticks induces resistance to Borrelia burgdorferi transmission. And multiple exposure to bites from uninfected sand flies prior to infection confer resistance to Leishmania major.
MJ Donovan, AS Messmore, MA McDowell, Uninfected mosquito bites confer protection against infection with malaria parasites, Infection and Immunity, 2007, 75, 2523-2530
Kamhawi SY, Belkaid G, Sacks D. Protection against cutaneous leishmaniasis resulting from the bites on uninfected sand flies, Science, 290:1351-1354
Immunoglobulins are associated with protection against malaria inoculation, by activating monocytes. The role of monocytes in malaria prophylaxis was first proposed by a research team from Uganda. Monocytes have a limited life span. In the absence of appropriate stimuli, they undergo apoptosis, but under the influence of survival signals, these cells differentiate into macrophages or dendritic cells. It has been shown that ligation of IgE on human monocytes markedly reduces the apoptosis. A cooperative, synergistic effect between immunoglobulins and monocytes was demonstrated. The addition of monocytes from healthy individuals to Plasmodium falciparum cultures in the presence of serum from immune individuals markedly inhibits the proliferation of the parasite in vitro. The activity of monocytes alone and immunoglobulins alone was moderate and inconsistent.
Patrick E Ogwang, Jasper O Ogwal, Artemisia annua L. Infusion Consumed Once a Week Reduces Risk of Multiple Episodes of Malaria: ARandomised Trial in a Ugandan Community Tropical Journal of Pharmaceutical Research June 2012; 13 (3): 445-453
S Khusmith, P Druilhe. Cooperation between antibodies and monocytes that inhibit in vitro proliferation of Plasmodium falciparum. Infection and Immunity, 1983, 219-223
Immunoglobulins protect efficiently by targeting α-gal on sporozoites immediately after inoculation by Anopheles mosquitoes; but not against the disease once the erythrocytic stage of malaria is established. IgE also interfers with the 14-3-3 ε protein during the invasion of hepatocytes by sporozoites. Antibodies are capable of blocking infection of the liver by Plasmodium falciparum. They could block infection at the pre-erythrocytic stage in several ways, either by neutralizing sporozoites directly, opsonizing sporozoites for phagocytosis or blocking invasion of sporozoites into hepatozoites.
Duarte J. Herbert F, Pied S, High levels of immunoglobulin E autoantibody to 14-3-3 epsilon protein correlate with protection against severe Plasmodium falciparum malaria, J Inf Dis 2012, 206, 1781-9
Orlandi-Pradines E, Almeras L, Rogier C, Antibody response against saliva antigens of Anopheles gambiae and Aedes aegypti in travellers in tropical Africa. Microbes Infect, 2007, Oct 9, 1454-62
Waitayakul A, Somsri S, Natural human humoral response to salivary gland proteins of anopheles mosquitoes in Thailand. Acta Trop 2008 Apr 98 66-73
Tapchaisri P, Asavanich A, Limsuwan S, Tharavanij S, Harinasuta KT. Antibodies against malaria sporozoites in patients with acute uncomplicated malaria and patients with cerebral malaria. Am J Trop Med Hyg. 1985 Sep;34(5):831-6.
N Katoh, S Kraft, T Biebeer. The high affinity IgE receptor (FcεRI) blocks apoptosis in normal human monocytes, Journal of Clinical Investigation, Jan 2000
The inhibition of sporozoite’s cell traversal activity seems to be an import element. The immunoglobulin 3D11 for example neutralizes 90% of the sporozoite infectivity by interacting with CSP. Circumsporozoite protein is the antigenic target of RTS,S and of other pre-erythrocytic malaria vaccines currently undergoing clinical trials.
S Mishra, R Hussenzeig. Antibodies to Plasmodium circumsporozoite protein CSP inhibit sporozoite’s cell traversal activity. J Immunol Methods 2012 377, 47-52.
Ferreira A, Monimoto T Use of DNA probe to measure the neutralization of Plasmodium berghei sporozoites by a monoclonal antibody. J Immunol 1987 138 , 1256-9
A similar protection mechanism by IgE has been documented for leishmaniasis. IgE antibodies bind strongly to promastigotes.
Lynch NR, Malavé C, Infante B, IgE antibody against surface antigens of Leishmania promastigotes in American cutaneous leishmaniasis, Parasite Immunol, 1986 8, 109-16.
It happens that Artemisia infusions are less efficient for non-immune Caucasians. It is probably not related to genetic strains, but to the absence of acquired immunity. In sub-Saharan Africa most people are almost continuously infected by Plasmodium falciparum parasites, and the majority of infected adults rarely experience overt disease. In naïve individuals Plasmodium falciparum infection is almost always symptomatic, and clinical symptoms can be observed at very low parasitemia levels.
D Doolan, C Dobano, JK Baird. Acquired immunity in malaria: Clinical Microbiology Reviews. Jan 2009, 13-36.
A study involving several African ethnic groups, some of caucasian ascent, others of the negroid type, was unable to detect genetic factors able to explain the significant differences in immune response.
D Modiano, V Petrarca, M Coluzzi, Different response to Plasmodium falciparum malaria in West African sympatric ethnic groups. Proc Natl Acad sci 1996 93, 13206-11.
But in an Indian study no circulating free antibodies were detected in some individuals. The significance of this trait present in some individuals deserves to be studied in depth.
Biswas S, Saxena QB, The natural occurrence of circulating antibodies in populations of endemic malarious disease. Indian J Malariol, 1990 27, 139-48
The total IgE level in a population is strongly related to the malaria endemicity in that area.

Country IgE ng/ml
Sweden 8
Madagascar 301
Thailand 647
Liberia 2134

H Perlmann, H Helmby, IgE elevation and anti-malarial antibodies in Plasmodium falciparum malaria. Cl
IgE titers are negatively correlated with gametocyte carriage and this may be an important factor in a area of high endemicity.
R Lawaly, L Konate, R Paul. Impact of mosquito bites on asexual parasite density and gametocyte prevalence in asymptomatic chronic Plasmodium falciparum infections and correlation with IgE and IgG titers. Infection and Immunology, 2012, 80. 2240-2246.
Baird JK, Jones Tr, Leksana B. Evidence for specific suppression of gametocytemia by Plasmodium falciparum in residents of hyperendemic Irian Jaya. Am J Tro Med Hyg, 1991, 44, 183-90.
During stage II to V gametocytes hide in the bone marrow for their development. IgE is well present in the bone marrow, it is even generated there in case of stress (anemia, drugs, parasites, bacteria…). Also mast cells originate from a bone marrow progenitor and subsequently develop different phenotype characteristics locally in tissues. Mast cells play an important protective role, are involved in wound healing, immune tolerance, defense against pathogens and blood-brain barrier functions. These cells are known to accumulate at sites of inflammation in response to parasite and bacterial infections. There they degranulate and set free histamines, IgE and TNF-alpha. Degranulation is proportional to parasitemia, increasing from virtually 0 to 40% in the case of complicated malaria. It is difficult to understand why gametocytes hide in the bone marrow for their development. Mast cells express a high affinity for IgE. Often mast cells are coated with IgE
Lee J, Veatch SL, Baird B, Holowka D. Molecular mechanisms of spontaneous and directed mast cell motility. J Leukoc Biol. 2012 Nov;92(5):1029-41. doi: 10.1189/jlb.0212091. Epub 2012 Aug 2.
P Wilainam, R Nintase, Mast cell activation in the skin of Plasmodium falciparum malaria patients. Malaria Journal, 2015, 14-67
Naohiro Watanabe, Takahisa Furuta. Cell-Derived TNF in Murine Malaria Protective Roles of Mast Cells and Mast J Immunol 2006; 177:3294-3302
A Corrado C Tipton, E Waller, Human IgE Plasma cells in the blood, nasal polyp and the bone marrow. Am J Resp Crit Care Med 193:2016:A6696
MacDermott RP, Jendrisak GA, Nash GS. Human rib bone marrow mononuclear cells spontaneously synthesize and secrete IgE in vitro. Clin Exp Immunol. 1991 Jan;83(1):163-8.
Artesunate is antagonistic with the formation of IgE and its mechanisms of action against parasites.
Cheng C, Wong WS, Anti-allergic action of anti-malarial drug artesunate in experimental mast cell-mediated anaphylactic models. Allergy, 2013, 68, 195-203
Wei M, Xie X, Dihydroartemisinin suppresses ovalbumin-induced airway inflammation and reduces IgE in a mouse allergic asthma model. Immunopharmacol Immunotoxicol. 2013 Jun;35(3):382-9. doi: 10.3109/08923973.2013.785559.
Worse even, a 5-fold increase in gametocytogenesis in Plasmodium falciparum has been documented for chloroquine in vitro.
Buckling A, Read AF. Chloroquine increases Plasmodium falciparum gametocytogenesis in vitro. Parasitology, 1999, 118, 339-46.
It is shocking to read in a recent paper that while chloroquine may significantly reduce mortality, but whether it will interfere with the host immune system is currently unknown. And the authors demonstrate in a mice model that a single dose of chloroquine soon after malaria infection significantly suppresses both the cellular and humoral immunity of the host. The authors conclude that chloroquine only is efficient in the well established erythrocytic stage by inhibiting hemozoin formation, but, if used in prophylaxis, may have dramatic impacts on the immune system and malaria prevalence.
Xiaosong Qin, Yaming Cao, Guang Chen Early Treatment with Chloroquine Inhibits the Immune Response against Plasmodium yoelii Infection in Mice. 271 Tohoku J. Exp. Med., 2014, 234, 271-285; doi: 10.1620/tjem.234.271.
This is not surprising as chloroquine reduces CD4+ activation.

Ralf L. J. Schmidt, Sabrina Jutz, Katrin Goldhahn, Chloroquine inhibits human CD4+ T-cell activation by AP-1 signaling modulation. Sci Rep. 2017; 7: 42191.
Is is dramatic negligence not to have studied in the European Institutes of Tropical Medicine and elsewhere the impact this inhibition of the of the immune system might have on prophylaxis and transmission and not to have alerted the African communities against these risks. Chloroquine is still massively sold in Africa and the second most preferred medicine after ACTs.
Conclusion
Thousands of research papers have been written on artemisinin. But this molecule has no effect on sporozoites and gametocytes, on prevention and transmission. Curative and preventive strategies for malaria treatment should ideally target three malarial life-cycle stages: exoerythrocytic forms, the asexual blood stages, and the transmission stages.

Lipids against malaria

janvier 9, 2018

Artemisia ketone, lipids and ketogenic diet.

Artemisia ketone is the major constituent of essential oil of Artemisia annua, often up to 60 %, in Artemisia afra up to 35%, in Artemisia absinthium 14% . But it is absent in many other Artemisia species, for example in East Russia

Radulović NS, Randjelović PJ, Stojanović NM, Blagojević PD, Stojanović-Radić ZZ, Ilić IR, Djordjević VB. Toxic essential oils. Part II: chemical, toxicological, pharmacological and microbiological profiles of Artemisia annua L. volatiles. Food Chem Toxicol. 2013 Aug; 58:37-49. doi: 10.1016/j.fct.2013.04.016
L Chagonda, C Makonda.The essential oil of cultivated Artemisia afra (Jacq.) from Zimbabwe. Flavour and Fragrance Journal Volume 14, Issue 2 March/April 1999 Pages 140–142
Anne Orav, Ain Raal, Elmar Arak, Mati Müürisepp, and Tiiu Kailas. Composition of the essential oil of Artemisia absinthium L. of different geographical origin; Proceedings of the Estonian Academy of Sciences.Chemistry. Volume 55 No. 3 September 2006 155–165
Gulmira Özek, Yerlan Suleimen, Nurhayat Tabanca, Chemical Diversity and Biological Activity of the Volatiles of Five Artemisia Species from Far East Russia. Rec Nat Prod 8:3, 2014, 242-261
Artemisia apiacea in old Chinese documents has the reputation to be more effective than Artemisia annua against malaria. It contains a lot of artemisia ketone but is very, very poor in artemisinine.
Artemisia annua from Luxembourg is very rich in artemisia ketone, probably because it is a wild chemotype similar to the one from Serbia studied by Radovic. High artemisinin hybrids do not contain any artemisia ketone or only traces
Artemisia annua herb of Chinese origin in pharmacies in Luxembourg and Germany has an average artemisinine content of 0.08% and the artemisia ketone content is very high at 42% of the essential oil. An analysis of Chinese Artemisia annua reported in 1990 even gives a value of 66.7 %.
Simon, J.E., Charles, D., Cebert, E., Grant, L., Janick, J., Whipkey, A., 1990. Artemisia annua L: a promising aromatic and medicinal. In: J. Janick and J.E., Simon (eds.) Advances in New Crops. Timber Press, Portland, Oregon, USA. 522-526
Most of these analytic data from the literature were confirmed by the extensive analytical work done at the Université des Montagnes, Cameroun and Laboratoire National de la Santé. Luxembourg.
Rosine Desiree K. Chougouo, Jonas Kouamouo, Titilayo O. Johnson, Dalia Fomekong Fotsop1, Gilbert Hansen, Pierre Lutgen, Marc Flies, Marc Fischer, Simon Sven, Lysette Kouemeni, Mathieu Tene, Denis Wouessidjiwe, Jean M. Tekam, Lazare Kaptue, Pierre Comparative study of chemical composition of Artemisia annua Essential oil from Cameroon and Luxembourg by µCTE/TD/GC/MS . North Asian International Research J Consortium NAIRJC ISSN 2454-2326
Our “antimalarial” interest was attracted upon artemisia ketone, by a paper from Serbia (Radulovic op.cit.) where they show that artemisia ketone has a stronger free radical scavenging effect and a stronger antimicrobial activity than other wellknown monoterpenes in Artemisia annua. It is important also to remember that thujone is a ketone with strong antimalarial properties and is present in significant concentrations in most artemisia species.
In studies on inflammation the plant from Luxembourg shows higher inhibition of IL-6 and IL-8 than Artemisia annua plants from other origins
de Magalhães PM, Dupont I, Hendrickx A, Joly A, Raas T, Dessy S, Sergent T, Schneider Y-J. Anti-inflammatory effect and modulation of cytochrome P450 activities by Artemisia annua tea infusions in human intestinal Caco-2 cells. Food Chemistry. 2012; 134:864–871
Our interest was further raised when we read in another recent paper.
David N. Ruskin Masahito Kawamura Jr, Susan A. Masino. Reduced Pain and Inflammation in Juvenile and Adult Rats Fed a Ketogenic Diet. PLOS 2009.doi.org/10.1371/journal.pone.0008349
that ketones can reduce pain and inflammation. We had noticed in our own work that during surgical interventions Artemisia annua has an antinociceptive effect.
Onimus M, Carteron S, Lutgen P (2013) The Surprising Efficiency of. Artemisia annua Powder Capsules. Med Aromat Plants 2: 125.
but we were not able to relate this precisely to one or several molecules. The PlosOne paper (D Roskin op.cit.) relates the antinociceptive effect to ketones, as they are generated in a ketogenic diet. The restricted carbohydrate content of ketogenic diet minimizes glucose metabolism and produces ketone bodies as alternate energy sources for heart and brain. The heart almost exclusively relies on lipid metabolism while Plasmodium during its erythrocytic stages produces its energy mainly through anaerobic glycolysis. Methylglyoxal is produced in larger quantities during glycolysis and is highly toxic. The most common pathway for methylglyoxal detoxification is based on glutathione which converts it to lactate. Lipids are more efficient than glucose to produce ATP, without leaving as much “garbage”. The byproduct of ketogenesis is acetone which is eliminated in urine or breath.
The name given to artemisia ketone may be misleading. It is a small linear molecule which is not parent of heavier molecules with several rings like artemisinic acid, arteannuin B or artemisinin.
A range of ketones act as antimalarials, for example chalcones. They inhibit the plasmodial cysteine protease enzyme. In in vivo trials run in India
SS Mahajan, VR Kamath. Synergistic antimalarial activity of ketones with rufigallol and vitamin C. Parasitology. Volume 131, Issue 4 2005, pp. 459-466
five ketones out of twenty showed good antimalarial activity, when tested individually. Nine out of twenty showed good activity, when tested in combination with rufigallol but none when tested with Vitamin C. Rufigallol is known for its oxidant properties and is by itself a strong antimalarial.
RW Winter, KA Cornell, LL Johnson. Potentiation of the Antimalarial Agent Rufigallol. Antimicrob ag and Chemotherapy, 1996, 40,6, 1408-11
It is likely that ketone bodies also work synergistically with other antimalarials, but it is possible that they are antimalarials per se. Several plants of the Asteraceae family well known as medicinal plants are rich in the ketone davanone: Artemisia pallens, persica, sieberi, herba alba, capillaris.
Is a high fat, ketogenic diet beneficial against malaria.
People living in the poorest countries are the most afflicted to malaria and this may be related to nutrition. Their basic staple is rich in carbohydrates (starch). The main source of energy is thus glucose, but not lipids and ketone bodies. Glucose is food for Plasmodium which needs 60 times more of this fuel than the healthy erythrocyte.
Fatty, ketogenic diet will provide less nutrients to the parasite although this has not been explored in depth. Breastfeeding seems to contribute to the immunity of newborns during 6 months and breast milk is rich in fat. Breast milk is also rich in taurine.
The effect of fatty ketogenic diet might also explain many anecdoctical results on the effect of lipids on Artemisia annua efficiency. In 2009 at the 2d Symposium on Tropical Diseases at Luxembourg, D Rezelman showed that the addition of arachid oil enhanced the efficiency of Artemisia annua extract by a factor 3 in mice. The Brewer Science Library reports that some physicians recommend to take artemisinin with whole milk, cod liver oil, almond oil or flaxseed oil. At the ICEI malaria conference at Roma in April 2010 B Isacchi from the Universitate di Firenze showed that olive extract enhanced the effectiveness of artemisinin. In 2011 clinical trials run by IFBV-BELHERB in Dagana, Senegal showed that a mixture of Artemisia annua leaf powder and peanut butter gave cure rates > 95%. Dr F Roelofsen (personal communication, 2012) showed that when Artemisia annua leaves mixed with 10% fatty yoghurt gave a higher AUC and an extension of half-life for artemisinin from 30 minutes to 2-3 hours.
There are several pathways to explain the positive effect of lipids delivered in conjunction with tea. It is possible that an oil rich diet has an effect on the erythrocyte membrane lipid composition, stimulation of calcium channels and permeability.
A Pagnan, R Corrocher, G Ambrosio. Effects of an olive-oil-rich diet on erythrocyte membrane lipid composition and cation transport systems. Clinical Science (1989) 76, 87-93 87
Lipids may increase the bioavailability of lipophilic substances like artemisinin or essential oils. This effect has been documented for lumefantrine
Ashley EA, Stepniewska K, Lindegårdh N, Annerberg A, Kham A, Brockman A, Singhasivanon P, White NJ, Nosten F. How much fat is necessary to optimize lumefantrine oral bioavailability? Trop Med Int Health. 2007 Feb;12(2):195-200.
The positive effect of a ketogenic diet on malaria is known since 60 years. In a trial in India, of 10 rats, 8 weeks old, 5 received a standard diet and 5 a ketogenic diet containing 93% per cent., butter. After a week, all were inoculated with Plasmodium berghei. The number of parasites observed daily and at the peak of infection was much less in the rats given the ketogenic diet.
S P Ramakrishnan. Studies on Plasmodium berghei Vincke and Lips 1948. 16. Effect of ketogenic diet on the course of blood-induced infection of rats. Indian Journal of Malariology 1954 Vol.8 pp.85-88
Mother’s milk is rich in fats: 4.4 % versus 3.3% in bovine milk. A fatty diet kills the sporozoites in the hepatocytes by mediating oxidative stress.
V Zusarte-Luis, MM Mota. Dietary alterations modulate susceptibility to Plasmodium infection. Nature Microbiology Letters, 25 Sept 2017
Cats and dogs are immune against malaria and this may be related to the fact that they can only survive on a diet with meat.
More recently this was confirmed in a French paper
Vincent Robert, Catherine Bourgouin, Delphine Depoix, Catherine Thouvenot, Marie-Noëlle Lombard and Philippe Grellier Malaria and obesity: obese mice are resistant to cerebral malaria Malaria Journal 2008 7:81 DOI: 10.1186/1475-2875-7-81
PubMed searches with « obesity » and « malaria » yielded 107,545 and 46,653 references, respectively. However, association of the two terms produced only 17 entries, indicating that the two communities of researchers occupy distinct scientific niches that do not overlap. Finally, a search in the French database of all recorded malaria cases (about 45,000) was eloquent: the bodyweight of the studied patients was simply not recorded
Dr. Elliot Joslin’s Diabetic Diet in 1923 consisted of « meats, poultry, game, fish, clear soups, gelatin, eggs, butter, olive oil » and contained approximately 5% of energy from carbohydrates, 20% from protein, and 75% from fat.
Recent research now finds that low-carbohydrate, ketogenic diet is effective for improving glycemia, reducing obesity and body weight.
William S Yancy, Marjorie Foy, Allison M Chalecki, Mary C Vernon and Eric C Westman. A low-carbohydrate, ketogenic diet to treat type 2 diabetes. Nutrition & Metabolism 2005 2:34 DOI: 10.1186/1743-7075-2-34
A review paper confirms these findings. It revisits the meaning of ketosis in the light of this evidence and considers possible mechanisms for the therapeutic actions of the ketogenic diet on different diseases. The present review also questions whether there are still some preconceived ideas about ketogenic diets, which may be presenting unnecessary barriers to their use as therapeutic tools in the physician’s hand.
Paoli A, Rubini A, Volek JS, Grimaldi KA. Beyond weight loss: a review of the therapeutic uses of very-low-carbohydrate (ketogenic) diets. Eur J Clin Nutr. 2014 May;68(5):641.
Diabetes, malaria and diet are fields which needs much more research.

Phytosterols, chlorogenic acid, cholesterol, virus

janvier 9, 2018

The Plasmodium parasite needs cholesterol for survival and multiplication. This fact was well documented in a WHO document in 1977 and in subsequent papers
George G. Holz, Jr. Lipids and the malarial parasite. Bull World Health Organ. 1977; 55(2-3): 237–248
Krishnegowda G, Gowda DC Intraerythrocytic Plasmodium falciparum incorporates extraneous fatty acids to its lipids without any structural modification. Mol Biochem Parasitol. 2003 Nov;132(1):55-8.
Moll GN, Vial HJ, Ancelin ML, Op den Kamp JA, Roelofsen B, van Deenen L. Phospholipid uptake by Plasmodium knowlesi infected erythrocytes. FEBS Lett. 1988 May 23;232(2):341-6.
Mi-Ichi F, Kita K, Mitamura T. Intraerythrocytic Plasmodium falciparum utilize a broad range of serum-derived fatty acids with limited modification for their growth. Parasitology. 2006 Oct;133(Pt 4):399-410.
The replicative capacity of Plasmodium liver forms is remarkable, achieving the fastest growth rates known. Plasmodium starts its lifecycle in the liver. Cholesterol either originates from the diet or is synthesized, mostly in the liver. Cholesterol and malaria sporozoites may use the same doorway into liver cells. A research group from Lisbon
Rodrigues, C. D., Hannus, M., Prudencio, M., Martin, C., Goncalves, L. A., Portugal, S. Mota, M. M. (2008). Host scavenger receptor SR-BI plays a dual role in the establishment of malaria parasite liver infection. Cell Host & Microbe, 4(3), 271-282. DOI: 10.1016/j.chom.2008.07.012
Hanson KK, Ressurreição AS, Beatty WL, Wirth DF, Hänscheid T, Moreira R, Marti M, Mota MM. (2013) Torins are potent antimalarials that block replenishment of Plasmodium liver stage parasitophorous vacuole membrane proteins. Proc Natl Acad Sci USA. 110(30): E2838-47
showed that the SR-BI receptor which is the entry port for HDL cholesterol also opens the door for malaria parasites. This establishes a first clear link between malaria infection and cholesterol uptake pathways, and a new intervention strategy against malaria. This was confirmed by CORDIS project 235864: uptake of exogenous cholesterol, rather than host cell de novo biosynthesis is important for the Plasmodium falciparum liver stage.
Infected erythrocytes contain twice as much cholesterol as the uninfected. Increases in the membrane surface area of the parasite, and in some cases of the erythrocyte, parallel parasite growth and segmentation. Augmentation of all the membrane systems of the infected erythrocyte causes the lipid content to rise rapidly, but the parasite lipid composition differs from that of the erythrocyte
Nirianne Marie Q. Palacpac, Yasushi Hiramine, Fumika Mi-ichi, Motomi Torii, Kiyoshi Kita, Ryuji Hiramatsu, Toshihiro Horii, Toshihide Mitamura. Developmental-stage-specific triacylglycerol biosynthesis, degradation and trafficking as lipid bodies in Plasmodium falciparum-infected erythrocytes. Journal of Cell Science 2004 117: 1469-1480; doi: 10.1242/jcs.00988
In vitro human HDL cholesterol is also necessary for the culture of P falciparum. Several intraerythrocytic growth cycles of Plasmodium falciparum could be achieved in vitro using a serum free medium supplemented only with a human high density lipoprotein (HDL) fraction (d = 1.063-1.210). The parasitemia obtained was similar to that in standard culture medium containing human serum. The parasite development was incomplete with the low density lipoprotein (LDL) fraction and did not occur with the VLDL fraction.
Devendra Bansal, Harinderpal Singh Bhatti and Rakesh Sehgal. Role of cholesterol in parasitic infections. Lipids in Health and Disease20054:10. DOI: 10.1186/1476-511X-4-10
Grellier P1, Rigomier D, Clavey V, Fruchart JC, Schrevel J. Lipid traffic between high density lipoproteins and Plasmodium falciparum-infected red blood cells. J Cell Biol. 1991 Jan;112(2):267-77.
In vivo Plasmodium continuously diverts cholesterol from hepatocytes and erythrocytes which leads to a lower cholesterol level in malaria patients. In malaria endemic areas significantly lower levels of cholesterol and triglycerides are found in children infected with Plasmodium falciparum.
Chuckwuocha, UM. and Eke, KN., Malaria parasite status and cholesterol level of malaria patients in the IMO River Basin Nigeria. Asian Pac J Trop Med., 4-12, 2011, 993-4
A recent paper from Saudi Arabia showed that Ithere is a significant inverse correlation between parasite count and cholesterol level in patients. The same effect on cholesterol depletion in murine malaria has been noticed. And more recently in malaria infected children in Cameroon, malaria patients presented significantly lower levels of total cholesterol and HDL cholesterol than control. On the other hand LDL cholesterol and triglycerides were higher.
A. Al-Omar, A.M. Eligail, R.M. Al-Ashban, A.H. Shah. Effect of falciparum malaria infection on blood cholesterol and platelets Volume 14, Journal of Saudi Chemical Society. Issue 1, January 2010, Pages 83–89 doi.org/10.1016/j.jscs.2009.12.013
Tuekam Kouam Hermine, Evaluation du profil lipidique chez les enfants paludens de 0 à 5 ans de Douala, Maîtrise en Biochimie, 2005, Université de Douala.
Several studies confirm the same trend. In summary, it may be said that HDL is significantly decreased, LDL moderately but VLDL and tryglycerides are increased. HDL cholesterol is essential for a good health. Too low values lead to general weakness, prostration and finally to death. The liver is also rich in glycogen, another nutrient for the parasites. Any perturbation in this power plant will put the parasite in a state of starvation and inhibit formation of merozoites. It had already been shown in 1957 that the liver glycogen of rats infected with Plasmodium berghei is depleted.
Mercado TI. Paralysis associated with Plasmodium berghei malaria in the rat13982. J. Infect Dis 1965 115:465–472
Different sterols occur in different life forms: cholesterol is the predominant sterol in vertebrates, ergosterol in yeast and other fungi, and phytosterols are the major sterols in plants. Most animal and human studies show that phytosterols reduce serum /or plasma total cholesterol and low density lipoprotein (LDL) cholesterol levels. Phytosterols are structurally very similar to cholesterol except that they always contain some substitutions at the C24 position on the sterol side chain. Plasma phytosterol levels in mammalian tissue are normally very low due primarily to poor absorption from the intestine and faster excretion from liver compared to cholesterol. It is however sufficient to displace cholesterol from the micelles. Phytosterols alter whole-body cholesterol metabolism in a dose-dependent manner. They increase the fecal cholesterol excretion.
Susan B Racette, Xiaobo Lin, Michael Lefevre, Catherine Anderson Spearie, Marlene M Most, Lina Ma, and Richard E Ostlund, Dose effects of dietary phytosterols on cholesterol metabolism: a controlled feeding study1 Jr Am J Clin Nutr. 2010 Jan; 91(1): 32–38.
A recent study from Maastricht shows that plant sterols not only reduce the bioavailability of cholesterol in a high fat diet but they also have a strong protective role in liver inflammation.
Jogchum Plat, Tim Hendrikx, Veerle Bieghs, Mike L. J. Jeurissen, Sofie M. A. Walenbergh, Patrick J. van Gorp, Ronit Shiri-Sverdlov. Protective Role of Plant Sterol and Stanol Esters in Liver Inflammation: Insights from Mice and Humans. PLOS October 30, 2014 doi.org/10.1371/journal.pone.0110758
The cholesterol lowering effect of plant sterols was discovered first in the early 1950s. Plant sterols have the same structure as cholesterol but have a higher solubility and are more easily hydrolyzed than cholesterol. Their presence in the intestine thus adversely affects the solubilization and absorption of cholesterol from food.
G V Vahouny, W E Connor, S Subramaniam, D S Lin, and L L Gallo. Comparative lymphatic absorption of sitosterol, stigmasterol, and fucosterol and differential inhibition of cholesterol absorption. Am J Clin Nutr May 1983 vol. 37 no. 5 805-809
This is the main reason phytosterols are added to margarine. But they are not all taken up to the same degree: it is higher for campesterol in many animal species. In the protozoan Paramecium they even are the main nutrient and cholesterol not. The question remains and needs to be resolved: do phytosterols reduce the number of merozoites and trophozoites because of the lower availability of cholesterol or are they a more efficient replacement? They could also promote hemozoin crystallization as cholesterol does.
Phytosterols are well present in many vegetal oils (on the average 600 mg/100g), in nuts and kernels like avocado (250 mg/kg) and in most vegetables (30mg/kg) and fruits (20 mg/kg). Medicinal herbs contain higher concentrations than other plants. The Artemisia genus contains around 200 mg of phytosterols per 100g of dry matter.
Bianca Ivanescu, PhD Thesis IASI University Romania, 2010
All species of Artemisia contain phytosterols.
Tan, RX; Lu, H; Wolfender, JL; Yu, TT; Zheng, WF; Yang, L; Gafner, S; Hostettmann, K.Mono- and sesquiterpenes and antifungal constituents from Artemisia species. Planta Med 1999, 65-1, 64-67)
Tang HQ, Hu J, Yang L, Tan RX. Terpenoids and flavonoids from Artemisia species. Planta Med. 2000 May;66(4):391-3.
A review of Chinese traditional herbal medicines confirms that they are rich in phytosterols. Some contain up to 280 mg/100g.
Han J, He M, Zhou S, Wang G. Analysis of phytosterol contents in food plant materials and Chinese traditional medicines. Wei Sheng Yan Jiu. 2009 Mar;38(2):188-91.
The fact that phytosterols have been neglected in the fingerprint analysis of A annua and other medicinal plants is because they are difficult to analyze. They lack a good chromophore and thus require derivatization for measurement by HPLC-UV.
The claim that a diet rich in dietary fibres may reduce the level of cholesterol could be related to the high concentration of phytosterols in fibres and dry plant matter. Nuts are claimed to reduce cardiovascular problems. But the dietary fibres or polysaccharides like inulin decrease cholesterol by themselves.
Elke A. Trautwein, Dörte Rieckhoff, and Helmut F. Erbersdobler. Dietary Inulin Lowers Plasma Cholesterol and Triacylglycerol and Alters Biliary Bile Acid Profile in Hamsters. J. Nutr. November 1, 1998 vol. 128 no. 11 1937-1943
Corn stigmasterols are also used in conditions of high uric acid such as gout and some types of arthritis. The same effect was noticed by (personal communication) for Artemisia annua stem infusions. It is also the case for the plant Costus igneus used in India as cure against urinary stones. The aqueous stem extract of this plant is very rich in stigmasterol and lupeol. All this is relevant to malaria because plasmodium generates pro-inflammatory uric acid.
Many medicinal plants are known for their hypolipidemic and hypoglycemic effect, essentially by the action of phytosterols. This is the case for Hypericum perforatum (St John’s Wort), Azaradirachta indica (Neem), Moringa olifeira, Hypoxis hemerocalliedea (African potato).
Artemisia plants are known for their lipid-lowering effect, an effect similar to that obtained with statins. The aqueous extracts of Artemisia sieberi significantly lower total cholesterol, HDL, LDL and triglycerides in diabetic rats.
Mansi K, Lahham J. Effects of Artemisia sieberi Besser (A. herba-alba) on heart rate and some hematological values in normal and alloxan-induced diabetic rats. J Basic ApplSci. 2008; 1(4): 57-62.
This is also the case for ethanolic extract of Artemisia princeps.
U J Jung, N-I Baek, , J-S Yoo, T S Jeong, K-T Lee, Y J Kang, M K Lee, H J Kim, J Y Yeo, M S Choi.The anti-diabetic effects of ethanol extract from two variants of Artemisia princeps Pampanini in C57BL/KsJ-db/db mice. Food Chem Toxicol 2007 Oct 22;45(10):2022-9.
A recent paper from Korea documents similar effects for Artemisia capillaris. Their results show that extracts of this plant enhance the lipid metabolism, reduce cholesterol, reduce hepatic lipid contents and the serum ALAT and ASAT levels.
Dong Wook Lim, Yun Tai Kim , Yu-Jung Jang, Young-Eon Kim and Daeseok Han . Anti-Obesity Effect of Artemisia capillaris Extracts in High-Fat Diet-Induced Obese Rats Molecules 2013, 18(8), 9241-9252; doi:10.3390/molecules18089241
In the erythrocytes it is likely that the parasite converts cholesterol into fragments and lipids, which are activating the hemozoin formation.
Orjih AU. On the mechanism of hemozoin production in malaria parasites: activated erythrocyte membranes promote beta-hematin synthesis. Exp Biol Med (Maywood). 2001 Sep;226(8):746-52.
Phytosterols are able to replace cholesterol in cell membranes. Artemisia plants differ from other plants by a higher proportion of stigmasterol than beta-sitosterol which is the predominant sterol in all plants. Stigmasterol was found to modify the properties of cell
Hac-Wydro K. The replacement of cholesterol by phytosterols and the increase of total sterol content in model erythrocyte membranes. Chem Phys Lipids. 2010 Sep;163(7):689-97. doi: 10.1016/j.chemphyslip.2010.07.001.
It also inhibits the synthesis of cholesterol much more than beta-sitosterol.
Phytosterols also inhibit isoprenylation of proteins in Plasmodium falciparum.
Yang C, Yu L, Li W, Xu F, Cohen JC, Hobbs HH. Disruption of cholesterol homeostasis by plant sterols. J Clin Invest. 2004 Sep;114(6):813-22.
To survive the parasite needs to digest the proteins present in cholesterol. The need of intracellular parasites to retrieve nutrients and fulfill their energy needs is achieved by manipulating the host metabolism. Apicomplexa parasites like Plasmodium have lost a substantial number of genes related to biosynthetic functions. Phytosterols may deactivate the parasite’s final digestive machinery, thus making it impossible to survive as it stops receiving nutrients.
The cholesterol absorption from test meals is substantially lower after consumption of phytosterol rich food.
Ostlund RE Jr, Racette SB, Stenson WF. Inhibition of cholesterol absorption by phytosterol-replete wheat germ compared with phytosterol-depleted wheat germ. Am J Clin Nutr. 2003 Jun;77(6):1385-9.
Some polysaccharides also have a cholesterol lowering effect.
Y Cheng, K Tang, S Wu, B Liu. Astragalus polysaccharides lowers plasma cholesterol through mechanisms distinct from statins. PLOS ONE 2011, 6, 11, e 27437
This leads to a depletion of erythrocyte membrane of cholesterol and inhibits the “raft” function of cholesterol for the inward transport of nutrients to the vacuole of the parasite
Sarah Frankland, Timothy Schneider, Salenna R. Elliott, Ellen Knuepfer, Alan F. Cowman, Chris I. Newbold and Leann TilleyDelivery of the Malaria Virulence Protein PfEMP1 to the Erythrocyte Surface Requires Cholesterol-Rich Domains. Eukaryotic Cell, 2006, 849-860
and the penetration of parasites into cells. Steroids and sterols may influence the biological membrane function of erythrocytes by modifying permeability, metabolite transport and energy metabolism. Research work from Colombia shows that the majority of merozoites are unable to invade RBCs which have been treated with steroids of Solanum nudum.
Mary Luz López, Silvia Blair, Jairo Sáez, Cesar Segura. Effect of Solanum nudum steroids on uninfected and Plasmodiumfalciparum-infected erythrocytes. Mem Inst Oswaldo Cruz, Rio de Janeiro, Vol. 104(5): 683-688, August 2009
This also is valid for viral infections. This was first described in a paper from India.
M.M. Abid Ali Khan, D.C. Jain, R.S. Bhakuni, Mohd. Zaim and R.S. Thakur Occurrence of some antiviral sterols in Artemisia annua (1991)., Plant Science (Ireland) 75, 161-165.
A study comparing the antiviral effect of 7 Artemisia species found that Artemisia annua was always the strongest and often stronger than acyclovir.
MK Karamoddini, SA Emami, MS Ghannad, A Sahebcar. Asian Biomedicine vol 5-1, 2011, 63-68.
Out of the 21 medicinal plants evaluated for their virus inhibitory activity against tobamoviruses on their test hosts reacting hypersensitively, extracts of Lawsonia alba, Artemisia annua and Cornus capitata showed high virus inhibitory activity. The virus inhibitory agent (s) occurring in A. annua plant was isolated by conventional methods and identified as sterols as sitosterol and stigmasterol.
M.M. Abid Ali Khan ∗, D.C. Jain, R.S. Bhakuni, Mohd. Zaim, R.S. Thakur. Occurrence of some antiviral sterols in Artemisia annua. Plant Science. Volume 75, Issue 2, 1991, Pages 161-165 doi:10.1016/0168-9452(91)90230-6
In another study, the sterols from Artemisia annua had higher virus inhibitory properties than other molecules from this plant, like artemisinin or arteannuin-B, and Artemisia annua had higher virus inhibitory activity than 20 other medicinal plants. Many viruses build up a cholesterol envelope to enter the cells. This is for example the case for influenza virus where envelope cholesterol depletion markedly influences influenza virus aggression.
Xiangjie Sun and Gary R. Whittaker. Role for Influenza Virus Envelope Cholesterol in Virus Entry and Infection. J Virol. 2003 Dec; 77(23): 12543–12551. doi: 10.1128/JVI.77.23.12543-12551.2003
Dengue virus infection increases intracellular cholesterol levels at early stages post infection by triggering the uptake of LDL particles.
Rubén Soto-Acosta, Clemente Mosso, Rosa María del Angel. The increase in cholesterol levels at early stages after dengue virus infection correlates with an augment in LDL particle uptake and HMG-CoA reductase activity. Virology, Volume 442, Issue 2, Pages 132-147
We need to report here an anecdotic report from Vanuatu. A major dengue fever outbreak took place in this island in 2014, with several hundred cases. A female person living in Vanuata was infected by this virus. The infection was classified as dengue by clinical analysis in the hospital where she spent a week. She claims to have recovered after drinking Artemisia annua infusion (origin of the herb: Luxembourg). Subsequently several of her relatives suffered from the same symptoms and were all cured in a few days after tea A annua consumption. The Health Authorities confirm that these people were infected by the dengue virus. This is the first in vivo report on the efficiency of Artemisia annua against dengue. It needs of course to be confirmed by clinical trials in accordance with the WHO protocol.
Saddi M, Sanna A, Cottiglia F, Chisu L, Casu L. Antiherpevirus activity of Artemisia arborescens essential oil and inhibition of lateral diffusion in Vero cells. Ann Clin Microbiol Antimicrob. 2007; 6.
Calderone V, Nicoletti E, Martinotti E. In vitro antiviral effects of an aqueous extract of Artemisia verlotorum Lamotte (Asteraceae). Phytother Res. 1998; 12:595-7.
Efferth T, Romero MR, Wolf DG, Stamminger T, Marin. JJG, Marschall M. The antiviral activities of artemisinin and artesunate. Clin Infect Dis. 2008; 47:804-11.
Abid Ali Khan MM, Jain DC, Bhakuni RS, Zaim Mohd Thakur RS. Occurrence of some antiviral sterols in Artemisia annua. Plant Sci. 1991; 75:161-5.
Several plants were studied in Colombia for their inhibitory effect against the yellow fever virus which is of the same Flavivirus genus as dengue. Essential oil from Artemisia vulgaris like several other plants seems to lead to a direct virus inactivation.
Rocío Meneses, Raquel E Ocazionez, Jairo R Martínez and Elena E Stashenko. Inhibitory effect of essential oils obtained from plants grown in Colombia on yellow fever virus replication in vitro. Annals of Clinical Microbiology and Antimicrobials20098:8. DOI: 10.1186/1476-0711-8-8
Proanthocyanidins also are efficient against virus.
Masahiko Takeshita, Yo-ichi Ishida, Ena Akamatsu, Yusuke Ohmori, Hiroaki Kataoka. Proanthocyanidin from Blueberry Leaves Suppresses Expression of Subgenomic Hepatitis C Virus RNA. J Biol Chem. 2009 Aug 7; 284(32): 21165–21176. doi: 10.1074/jbc.M109.004945
Beta-sitosterol and stigmasterol inhibit pro-inflammatory leukines TNF-α, IL-1β. Il-8 and are probably responsible for the anti-osteoarthritic properties of Artemisia tea. Stigmasterol is a phytosterol with potential anti-osteoarthritic properties
O. Gabay, C. Sanchez, C. Salvat, F. Chevy, M. Breton, G. Nourissat, C. Wolf. Stigmasterol: a phytosterol with potential anti-osteoarthritic properties. DOI: doi.org/10.1016/j.joca.2009.08.019. Osteoarthritis and Cartilage, 2010, 18, 106-116.
Stigmasterol and β-sitosterol from Artemisia ageratum are effective topic anti-inflammatory agents.
M. A. G ómez, M. T. Sáenz, M. D. G arcía and M. A. Fernández. Study of the Topical Anti-Inflammatory Activity of Achillea ageratum on Chronic and Acute Inflammation Models. Z.Naturforsch, 54c, 1999, 937-941
Infection with HIV is also associated with elevated IL-6 levels and production which phytosterols are able to lower.
Breen EC, Rezai AR, Nakajima K, Beall GN, Martinez-Maza O Infection with HIV is associated with elevated IL-6 levels and production. J Immunol. 1990 Jan 15;144(2):480-4.
In fact, the antiviral effect of β-sitosterol and stigmasterol from Artemisia annua is well known by the Chinese, since 30 years.
Tan RV, Zheng WF, Tang HQ. Biologically active substances from the genus Artemisia. Planta Med. 1998; 64:295-302.
This antiviral effect however is not an inherent property of these molecules but attributable to enhanced activity of cell-mediated immune response which controls viral replication.
The antiviral properties of β-sitosterol and β-sitosterol glucoside have event been patented.
against HIV. They stabilize the CD4 of infected persons and reduce the IL-6. The authors of the patent describe these effects in a paper.
Use of a combination of beta-sitosterol and beta-sitosterol glucoside for treating HIV infection EP 0858806 A1
Bouic PJ, Lamprecht JH. Plant sterols and sterolins: a review of their immune-modulating properties. Altern Med Rev. 1999 Jun;4(3):170-7.
Artemisia plants are also rich in chlorogenic acid and other caffeoylquinic acids and are used for the treatment of hepatitis and other viral diseases. And as the Chinese claim the plant Artemisia annua contains other interesting and potent molecules.
Zhan Y, Geng CA, Chen JJ, Anti-HBV active chlorogenic acid analogues from Artemisia capillaris as a tradional Chines herb for treating hepatitis. J Ethnopharmacol 2014 156 147-54
Wenwen Zhao, Weina Zhang, Kewe Dai, Identification and purification of novel chlorogenic acids in Artemisia annua. J Exp Biol and Agricult Sc. ISSN 2320-8694
Wu YH, Hao BJ, Anti-hepatitis B virus effect and possible mechanism of action of 3,4-o-dicaffeoylquinic acid in vitro and in vivo. Evid Based Complement Anternat Med, 2012:356806
Ding Y, Cao Z, Xiao W, Antiviral activity of chlorogenic acid against influenza A (H1N1/H3N2 virus. Sci Rep 2017 10:7:45723
Heyman HM, Senejoux F, Meyer JJ, Idenditication of anti-HIV active dicaffeoylquinic and tricaffeoylquinic acids. Fitoterapia. 2015 103. 155-164.
MM Makola, IA Dubery, NE Madala, The effect of geometric isomerism of 3,5.dicaffeoylquinic acid on its binding affinity to the HIV-Integrase enzyme. Evid Based Compl Aölter Medicine, 2016, article 4138263.
The antiviral and antimalarial properties of Inula viscosa are well known in the Middle East. The plant is rich in dicaffeoylquinic acid
M. Akkawi. Abbasi, S. Jaber, Q. Aburemeleh, A. Naseredin and Pierre Lutgen. Investigation of Traditional Palestinian Medicinal Plant Inula viscosa as Potential Antimalarial Agent British Journal of Pharmacology and Toxicology 2014
Dicaffeoylquinic acid in propolis also has antiviral properties.
T Takemura. K Kuwata. 3,4-dicaffeoylquinic from Brazilian propolis extends the lifetime of mice infected with the Influena A virus. Evid Based Compl Alt Med, 2012 article 946867
Breaking news on anti-HIV had already come from the University of Leiden in 2012. This was confirmed recently by a US study and they relate this anti-HIV property to dicaffeoylquinic acids.
Andrea Lubbe, Isabell Seibert, Thomas Klimkait, Frank van der Kooy. Ethnopharmacology in overdrive: The remarkable anti-HIV activity of Artemisia annua. Journal of Ethnopharmacology (2012) JEP-7371;
X Zheng, R Renslow, M Makola, E Baker. Structural eleucidation of cis/trans dicaffeoylquinic acid J Phys Chem Letters 2017, 8, 1381-1388.
A Japanese patent describes the antiviral properties od Artemisia absinthium
Nakamura T, Matsuda Kosuke. Virus diffusion preventing agent obtained from Artemisia absinthium WO/2015/155903