In vitro and in vivo activity of Aloe vera leaf exudate in experimental visceral leishmaniasis.
The leishmanicidal activity of Aloe vera leaf exudate (AVL) has been demonstrated in promastigotes and axenic amastigotes, but its effectiveness in animal models has not been evaluated. The presence of alkaloids, triterpenes, cyanidines, proanthocyanidines, tannins, and saponins in AVL was identified. Its effectiveness in four Leishmania donovani strains was studied both in promastigotes (IC50 ranged from 70-115 microg/ml) and amastigotes (IC50 ranged from 3.1-11.4 microg/ml). In amastigotes, the killing by AVL was facilitated through its induction of nitric oxide in leishmania-infected macrophages. The safety index was good as AVL up to 300 microg/ml remained non-toxic to monocytes and macrophages. In a L. donovani BALB/c mouse model, oral or subcutaneous administration of AVL (15 mg/kg body weight x 5 days) reduced parasitemia by >90% in the liver, spleen, and bone marrow without impairment of hepatic and renal functions. Collectively, we conclude that AVL shows promising antileishmanial activity and may provide a new lead agent in the treatment of Leishmaniasis.
Dutta
Avijit
A
Department of Infectious Disease and Immunology, Indian Institute of Chemical Biology, 4 Raja SC Mullick Road, Kolkata 700032, India.
Sarkar
Debjani
D
Gurib-Fakim
Ameenah
A
Mandal
Chitra
C
Chatterjee
Mitali
M
D000504:Aloe / Q000737:chemistry*; D000818:Animals; D000981:Antiprotozoal Agents / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use* / Q000633:toxicity; D001853:Bone Marrow / Q000469:parasitology; D002470:Cell Survival; D020128:Inhibitory Concentration 50; D007893:Leishmania donovani / Q000187:drug effects*; D007898:Leishmaniasis, Visceral / Q000188:drug therapy*; D008099:Liver / Q000469:parasitology; D008264:Macrophages / Q000187:drug effects / Q000276:immunology / Q000469:parasitology; D051379:Mice; D008807:Mice, Inbred BALB C; D009569:Nitric Oxide / Q000096:biosynthesis; D018512:Parasitemia / Q000188:drug therapy; D021261:Parasitic Sensitivity Tests; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use* / Q000633:toxicity; D013154:Spleen / Q000469:parasitology
D000981:Antiprotozoal Agents; D010936:Plant Extracts; D009569:Nitric Oxide