Modulatory effects of Momordica balsamina on Th1/Th2 cytokine profiles in immune-challenged rats

Abstract

There is an ever-growing interest to identify plants that boost the immune system functions. The objective of the present study was to evaluate the immunomodulatory effects of Momordica balsamina (MB) leaves extract in BCG-immunized rats. Thirty rats were randomly divided into five groups (n = 6). MB extract was suspended in 1% carboxymethyl cellulose (CMC). Firstly, animals were challenged subcutaneously with 0.05 ml BCG. The first group (vehicle control group) received 1% CMC (100 mg/kg body weight; p.o.), and the second group (positive control group) was provided with levamisole (18 mg/kg body weight; p.o.). The remaining groups (test groups) were dosed orally with different doses of MB extracts (50, 100 and 200 mg/kg body weight) for 14 consecutive days. Blood samples were collected on day 0, 7 and 14, and then plasma samples were analyzed for Th1 cytokines (TNF-α and IFNγ) and Th2 cytokines (IL-10 and TGF-β), using cytokine specific enzyme-linked immunosorbant assay (ELISA). MB extracts significantly increased (p ≤ 0.01) IFN-γ production in a doseand time-dependent manner and elicited significant increase (P ≤ 0.05) of TNF-α level at the dose 200 mg/kg after 14 days. Low doses (50 and 100 mg/kg) significantly increased (p ≤ 0.05) TGF-β levels while a high dose (200 mg/kg) significantly (p ≤ 0.05) reduced TGF-β levels in a time-dependent manner. No significant changes were observed on IL-10 level after plant extract treatment. MB shows immunostimulatory effects and significantly activates cell-mediated immunity.