In vitro antileishmanial activity and apoptosis induction of Pleurotus ostreatus alcoholic extract on Leishmania major

Abstract

<strong>Background and objectives: </strong>Leishmaniasis is caused by the genus <em>Leishmania</em>. Medications such as antimony compounds for the treatment of the disease are associated with limitations along with several side effects and disease recurrence; thus, evaluation of natural compounds with history of antimicrobial properties such as <em>Pleurotus ostreatus</em>, is of a great importance. The purpose of this study was to evaluate the apoptotic and leishmanicidal effects of <em>Pleurotus ostreatus</em> alcoholic extract on <em>Leishmania major </em>promastigote <em>in vitro.</em> <strong>Methods:</strong> Different concentrations of <em>Pleurotus ostreatus</em> extract (50, 100, 150, 200 and 250 μg/mL) were tested at 6, 24, 48 and 72 h on <em>Leishmania major</em> (MRHO/IR/75/ER) promastigotes. The leishmanicidal effects were determined using MTT [3-(4,5-dimethyl thiazolyl- 2)-2,5-diphenyle tetrazolium bromide] assay. Also, apoptosis induction was measured by flow cytometry and DNA fragmentation analysis. <strong>Results:</strong>The MTT results showed that leishmanicidal effect of <em>Pleurotus ostreatus</em> extract was dependent to extract concentration in a way that the lowest number of live promastigotes was obtained after treatment with 200 μg/mL of extract preparation at 72 h. The IC₅₀ of <em>Pleurotus ostreatus</em> extract was 160±2 μg/mL. Flow cytometric analysis showed that the extract could induce apoptosis in promastigotes at its IC₅₀. Also, the result of gel electrophoresis showed that DNA fragmentation of treated promastigotes at the same concentration. <strong>Conclusion:</strong> The results indicated that <em>Pleurotus ostreatus </em>alcoholic extract have a strong toxic effect on cultivated <em>Leishmania</em> parasites. Based on these results <em>in vivo</em> studies using rodent models and human cutaneous leishmaniasis CL is recommended.