Experimental chemotherapy with Allium sativum (Liliaceae) methanolic extract in rodents infected with Leishmania major and Leishmania donovani.
OBJECTIVE
Several plant products have been tested and found to possess antileishmanial activity. The present study was undertaken to establish whether methanolic extract of Allium sativum Linn has antileishmanial activity in comparison to standard drugs.


METHODS
Methanolic extract of A. sativum bulbs was screened for in vitro and in vivo antileishmanial activity against Leishmania major strain (NLB 145) and L. donovani strain (NLB 065). Pentostam and Amphotericin B were used as standard drugs. BALB/c mice and golden hamsters (Mesocricetus auratus) were used in in vivo studies on L. major and L. donovani respectively.


RESULTS
The extract exhibited very low cytotoxicity (IC50 >450 μg/ml) against Vero cells. The extract had significantly better (p <0.001) leishmanicidal activity against both species (IC50 34.22 μg/ml to L. major, 37.41 μg/ml to L. donovani) than Pentostam. However, the activity was significantly lower (p <0.001) than that of Amphotericin B against both the species. At a concentration of 250 μg/ml, the extract induced the production of 60 μM of nitric oxide, a ten-fold up-regulation in activated macrophages. The multiplication indices for L. major amastigotes treated in 100 μg/ml were significantly different (p <0.05). Treatment with the extract, daily for 28 days led to a significant reduction (p <0.05) in footpad swelling in BALB/c mice; similar activity noticed in the treatment with standard drugs. The Leishman-Donovan Units (LDU) for the extract treated animals were significantly higher (p <0.05) than those of standard drugs, but lower compared to the negative control.


CONCLUSIONS
Since the mechanism of action for the methanolic extract is apparently immunomodulatory, garlic compounds could be purified and tried as complementary medicine in the management of leishmaniases.
Wabwoba
Byrum W
BW
Mombasa Technical Training Institute, Department of Applied Sciences, Mombasa, Kenya. bwabwoba@gmail.com
Anjili
Christopher O
CO
Ngeiywa
Moses M
MM
Ngure
Peter K
PK
Kigondu
Elizabeth M
EM
Ingonga
Johnstone
J
Makwali
Judith
J
D000818:Animals; D000967:Antimony Sodium Gluconate / Q000008:administration & dosage; D000981:Antiprotozoal Agents / Q000008:administration & dosage* / Q000009:adverse effects; D002522:Chlorocebus aethiops; D006224:Cricetinae; D004195:Disease Models, Animal; D005737:Garlic / Q000737:chemistry*; D006801:Humans; D007893:Leishmania donovani / Q000187:drug effects* / Q000502:physiology; D018320:Leishmania major / Q000187:drug effects* / Q000502:physiology; D007896:Leishmaniasis / Q000188:drug therapy* / Q000469:parasitology; D008647:Mesocricetus; D000432:Methanol / Q000737:chemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D010936:Plant Extracts / Q000008:administration & dosage* / Q000009:adverse effects; D014709:Vero Cells
D000981:Antiprotozoal Agents; D010936:Plant Extracts; D000967:Antimony Sodium Gluconate; D000432:Methanol