Qinghaosu derivatives in protozoal diseases & schistosomiasis

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Hi All,

 

I asked if Qinghao, or its derivatives had been tried in protozoal

diseases other than malaria.

 

Yesterday, I did a Medline search on the topic. Here is a summary:

 

Quinine (from Jinjinapi Cx Cinchonae, Peruvian Bark) was one of

the first antiprotozoal, esp antimalarial, drugs. Jinjinapi is bitter and

its actions include: Febrifuge; Appetiser; Ease Spasm /

Spasmolytic; Antiprotozoal; ST-Antacid; Calm HT; Digestive. Its

clinical uses include: Stress; HT~palpitation; general debility;

protozoal infection; malaria & fever; SP~enlarged / splenomegaly;

muscle spasm / cramp; myalgia (fibromyalgia); anorexia;

indigestion; dyspepsia; ST hyperchlorhydria / acidity. It is

contraindicated in Pregnancy; TOXIC; excess may cause

blindness & coma; Used in malaria & given in pregnancy only to

malaria sufferers under professional guidance

 

In recent years, Qinghaosu/artemisinin derivatives have been

shown to have potent antimalarial effects, even in multi-drug-

resistant strains of Plasmodium falciparum.

 

Qinghaosu (artemisinin, artemesinin, artemisinine) is an active

ingredient of Qinghao (Herba Artemisiae (Artemesiae) annuae).

Qinghaosu/Artemesinin derivatives include dihydroqinghaosu

(dihydroartemisinin (dihydroartemisinine)), arteether, beta-arteether,

artelinate, artelinic acid, beta-artelinic acid, artemether, beta-

artemether, artesunate and artesunic acid.

 

There is some evidence from research in-vitro, and in lab animals,

that some of these derivatives have other antiprotozoal effects, for

example in avian coccidiosis (Eimeria spp), babesiosis,

Neosporiasis and toxoplasmosis (T. gondii).

 

Artemisinin derivatives also have useful activity against

schistosoma (fluke) spp, in humans.

 

Combination of clindamycin & quinine has been the traditional

therapy to treat human Babesia microti infections but some

patients have not responded to this regimen. Babesia resistance to

atovaquone is documented. However, combination of azithromycin

& atovaquone/quinine can treat resistant human & animal

babesiosis. Arteether+buparvaquone combination could be a better

choice than imidocarb for treating Babesia equi infection, but

further trials are required.

 

Azithromycin combined with paromomycin shows promise to treat

cryptosporidiosis (and toxoplasmosis when combined with

pyrimethamine) in patients with the acquired immunodeficiency

syndrome (AIDS).

 

HOWEVER, Qinghaosu derivatives are NOT free of side effects.

High doses, or prolonged use can cause neurotoxicity and other

side-effects.

 

Also, see this:

 

Int J Parasitol. 1998 Jul;28(7):1131-40. Dietary modulation of avian

coccidiosis. Allen PC, Danforth HD, Augustine PC. USDA/ARS,

Livestock and Poultry Sciences Institute, Parasite Biology and

Epidemiology Laboratory, Beltsville, MD 20705, USA. During the

past several years, our laboratory has been investigating the

anticoccidial activities of various natural products that have

potential use as dietary supplements for coccidiosis control.

Sources of fats containing high concentrations of n-3 fatty acids

such as menhaden oil and flaxseed oil and flaxseed, when added

to starter rations and fed to chicks from one day of age, effectively

reduce lesions caused by the caecal parasite Eimeria tenella, but

not lesions caused by Eimeria maxima. Our results are consistent

with reports of effects of diets high in n-3 fatty acids on other

protozoan parasites which suggest that the state of oxidative

stress induced by these diets in the cells of both host and

parasites is responsible for their parasitic actions. Artemisinin, a

naturally occurring (Artemisia annua) endoperoxide and effective

antimalarial significantly lowers lesions from E. tenella when given

at low levels as a feed additive. The mechanism of its action is also

considered to involve induction of oxidative stress. Diets

supplemented with 8 p.p.m. gamma-tocopherol (abundant in

flaxseeds) or with 1% of the spice tumeric, reduce mid-small

intestinal lesion scores and improve weight gains during E. maxima

infections. These compounds may exert their anticoccidial activity

because they are effective antioxidants. Betaine, a choline

analogue found in high concentrations in sugar beets, improves

nutrient utilisation by animals under stress. When provided as a

dietary supplement at a level of 0.15% it has enhanced the

anticoccidial activity of the ionophore, salinomycin. Betaine may

act as an osmoprotectant whereby it improves the integrity and

function of the infected intestinal mucosa. In in vivo studies, betaine

plus salinomycin significantly inhibit invasion of both E. tenella and

E. acervulina. However, subsequent development of E. acervulina is

inhibited more effectively with this combination treatment than

development of E. tenella. Publication Types: · Review ·

Review, Tutorial PMID: 9724884 [PubMed - indexed for MEDLINE]

 

 

Best regards,

 

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