A blog posted on www.malariaworld.org on June 21. 2014 « Aspirin and artemisinin, beware » and another one on July 8 of the same year « Antiretrovirals and antimalarials : a deadly mix » had already highlighted the fact that drugs sold on a large scale in Africa showed strong antagonism with several antimalarial drugs. ARVs reduce the concentration of artemether , quinine, malarone in the blood. Aspirin has an effect on the endothelium and platelet adherence.
Pierre Lutgen's blog
A paper published twenty years ago should have attracted more attention (NM Anstey et al., J Exp Med 1996, 184, 557-567) : the suppression of NO synthesis in cerebral malaria appears to enhance pathogenesis and increased NO synthesis protects against clinical disease. The work was based on in vivo results obtained in Tanzanian children. Already five years earlier the killing of Plasmodium falciparum in vitro by nitric oxide derivatives (NO, nitrite, nitrate) had been demonstrated (KA Rockett et al., Infection and Immunity, 1991, 59, 3280-3283).
Plasmodium falciparum generates substantial amounts of ammonia as a metabolic by-product, but lacks detoxification mechanisms (S Kimoloi et al., Hypothesis and Theory, 2015, 9,article 234). It imports large amounts of glutamine from the host serum. Deamidation and deamination reactions generate two molecules of ammonia per glutamine molecule, particularly in the early trophozoite stages (T Zeuthen et al., Mol Microbiol 2006, 61, 1598-608).
A review paper published by Frank van der Kooy in 2013 (Journal of Ethnopharmacology, 150, 1-13) revived our interest in the question why the solubility of artemisinin is higher in Artemisia annua infusions than for the pure substance in distilled water.
Parasites are endowed with powerful and host-independant mechanisms which de novo synthesize or regenerate reduced glutathione (GSH) and protect the parasites from oxidative damage. GSH can penetrate from the extracellular space into the host cytosol but the parasite membrane is impermeable to peptides (H Atamna et al., Eur J Biochem 1997, 15, 670-9).. Glutathione is one of the most powerful anti-oxidants. It is a tripeptide formed by the amino acids glycine, cysteine and glutamic acid. It inhibits the action of arginine which produces NO and expels it from the food vacuole.
200 years ago, in 1830 the anthelmintic properties of santonin were discovered , simultaneously by Dr Kahler in Düsseldorf and Dr Alms in Mecklenburg in a plant from Turkestan, Artemisia cina. Its presence, although at lower concentrations, was later found in Artemisia maritima, Artemisia campesris, Artemisia gallica, Artemisia absinthium, Artemisia sieberi. (Berichte der Deutschen Chemischen Gesellschaft , 1867, Vol 6, 875-1670). Stanislao Cannizzaro is known widely for his , "Sunto di un corso di filosofia chimica", on santonin which he presented at the Karlsruhe Congress of 1860.
In 1957 the University of London found that dietary cod liver oil suppressed the multiplication of Plasmodium berghei in mice (DG Godfrey, Experimental Parasitology, 1957, 6, 555-565), of Babesia rodhaini (DG Godfrey, Experimental Parasitology 1957, 6-5, 465-485) and of Trypanosoma congolense (D G Godfrey , Experimental Parasitology, 1958, 3, 255-268).
Bilharzia, schistosomiasis, snail fever, is a disease caused by parasitic worms of the Schistosoma type. It may infect the urinary tract or the intestines. Signs and symptoms may include abdominal pain, diarrhea, bloody stool, or blood in the urine. In those who have been infected for a long time, liver damage, kidney failure, infertility, or bladder cancer may occur. Schistosomiasis affects almost 210 million people worldwide, and an estimated 200,000 people die from it a year,
A team of medical doctors and traditional healers in the Eastern part of the DR Congo just completed the first part of clinical trials studying the efficacy of Artemisia annua against gametocytes. The trials were following a protocol based on the procedures recommended by WHO and are coordinated with a team of medical doctors from France.
Polyphenols are a large group of antioxidants naturally known for their protective effect against oxygen metabolites, acting as free radical scavengers. In contrast to the beneficial effects it has recently been reported that some polyphenols may promote oxidative damage. These harmful effects are suspected to result from a pro-oxidant action.