In vivo immunomodulatory effects of the methanolic leaf extract of Gymnema sylvestre in Swiss albino mice

Abstract

In the present study we performed a comparative phytochemical analysis of the immunomodulating activities of the methanol leaf extract of Gymnema sylvestre (MLEGS) in Swiss albino mice. The phytochemical screening conducted on MLEGS revealed the presence of several phytoconstituents, including saponins, alkaloids, glycosides, phenols, tannins, and flavonoids. Immunomodulatory activities were determined by hemagglutination antibody (HA) titer and delayed-type hypersensitivity (DTH) tests for determining specific and non-specific immune responses. Flow cytometric techniques were performed for the estimation of B lymphocytes (CD3 and CD19) and Th2 cytokines (IL-2, IFN-? and IL-4). The response produced by oral administration of MLEGS elicited a significant reduction in a dose-related manner in the primary and secondary antibody response and DTH response. The response produced by oral administration of MLEGS elicited significant reduction in a dose-related manner in the primary and secondary antibody and DTH responses, with maximum reduction observed at 200 mg/kg-body wt. The maximal reductions in the production of CD3, CD19, IL-2, IFN-? and IL-4 were 31.59, 32.12, 29.51, 32.45 and 33.53%, respectively, at 200 mg/kg body weight. This study demonstrates that G. sylvestre exerts immunosuppressive effects on the components of the immune system of mice, and points to its significant immunomodulatory potential.