EFFECTS OF Acacia polyacantha CRUDE BARK EXTRACTS ADMINISTRATION IN MICE INFECTED WITH Leishmania donovani.

Abstract

Visceral leishmaniasis (kala-azar) is the severest form of leishmaniasis and is ranked the second deadliest parasitic disease in the world after malaria. Drugs of choice for the treatment of kala-azar are Pentavalent antimonials and Amphotericin B (AmB), which are toxic, and costly and the causative parasites are becoming resistant to them. Cheaper and safer alternative medicines are needed. Acacia polyacantha has shown medicinal properties. This study investigated the in vitro and in vivo efficacy of methanolic and aqueous crude bark extracts of Acacia polyacantha against Leishmania donovani. Experimental mice were infected with L. donovani and treated with plant extract, conventional drugs, and PBS. Their spleen weights and parasite loads were measured and equated between the groups. Data analysis was done using T-test and ANOVA to establish any statistically significant differences in the tested parameters. P values of < 0. 05 were considered significant. It was found that the crude bark extract of A. polyacantha, is potent against L. donovani with MIC of 1.47mg/ml. Spleen weight means of BALB/c mice were significantly reduced by aqueous crude bark extract of A. polyacantha by 44% in SAB mice while the methanolic crude bark extract reduced spleen parasite loads by 63% in BALB/c mice, when the extracts were given intra-peritoneally. The methanolic bark extract of A. polyacantha was more effective, reducing spleen parasite loads by 63% compared to a reduction of 32% using the aqueous crude bark extract in BALB/c mice when both extracts were given by intra-peritoneal route. The study found that the intra- peritoneal route was more effective than the oral route in reducing spleen parasite loads ( IP, LDU = 5.99) and (Oral, LDU = 15.34 ) in SAB mice, the difference was statistically significant (p < 0.05). The study concluded that the methanolic crude bark extract of A. polyacantha, administered intra-peritoneally was potent in lowering spleen parasite loads. The study recommends that the methanolic Acacia polyacantha bark extract should be administered intra-peritoneally to reduce spleen parasite loads in primates before humans. Further studies should be done on root and leaf extracts of A. polyacantha to establish if they have better action against L. donovani