Experimental therapeutic studies of Solanum aculeastrum Dunal. on Leishmania major infection in BALB/c mice

OBJECTIVES Solanum acueastrum Dunal. has been shown to have some chemotherapeutic value. Leaf and berry water and methanol compounds of S. acueastrum were evaluated for possible antileishmanial activity In vivo on BALB/c mice and in vitro against Leishmania major promastigotes, amastigotes and vero cells. MATERIALS AND METHODS Dry S. aculeastrum berry and leaf material were extracted in methanol and water. L. major parasites were exposed to different concentrations of S. aculeastrum fruit and leaf compounds and the IC50 on the promastigotes, percentage of infection rate of macrophages by amastigotes and the toxicological effect on vero cells were determined. BALB/c mice were infected subcutaneously with 1×10(6) promastigotes and kept for four weeks to allow for disease establishment. Infected mice were treated with fruit and leaf methanolic and water compounds, amphotericin B (AmB), and sterile phosphate buffered saline (PBS). RESULTS Fruit methanol compound was most effective in inhibiting the growth of promastigotes with IC5078.62 μg/ml. Fruit water compound showed the best activity in inhibiting infection of macrophages by amastigotes. Fruit methanol compound was more toxic at Ld50=8.06 mg/ml to vero cells than amphotericin B. Analysis of variance computation indicated statistically significant difference in lesion sizes between experimental and control mice groups (P=0.0001). Splenic impression smears ANOVA indicated a highly significant difference in parasitic numbers between the experimental and the control groups (P=0.0001). CONCLUSION The results demonstrate that compounds from S. aculeastrum have potential anti-leishmanial activities and the medicinal use of the plant poses considerable toxicity against dividing vero cells.