Anti-inflammatory Activity of Methanolic Extract of Memecylon umbellatum: In vitro and In vivo Experimental Evidences

Abstract

In the present study, the methanolic leaf extract of Memecylon umbellatum (MLMU) was evaluated for anti-inflammatory activity in in vitro and in vivo models. Initially, the MLMU was evaluated on C2C12 cell lines, and the levels of pro-inflammatory cytokines, IL-6 mRNA levels were measured. Later, the MLMU at 250 mg/kg was evaluated on the carrageenan-induced paw edema model in db/db mice, and in this model, the paw edema and histopathological evaluations were performed. In MTT assay, the MLMU exhibited very negligible cytotoxicity at all the concentrations tested (0.1 to 1 mg/ml) in C2C12 cell lines. Further, In C2C12 cell lines, the positive control group exposed to 1 ng/ml TNF-α for 48 hours, showed a significant elevation of IL-6 mRNA levels compared to control. Interestingly, the reference standard indomethacin (p<0.001) and MLMU (500 μg/ml) (p<0.001) have significantly inhibited the elevation of IL-6 mRNA levels compared to the positive control. Further, in the in vivo experiment, intraplantar administration of carrageenan caused a significant increase in the paw volume in the positive control compared to control (p<0.001). Further, histopathology of the paw showed significant inflammatory changes such as edema, vascular congestion, leukocyte infiltration, and necrosis in the positive control group compared to control. However, pretreatment with indomethacin and MLMU have significantly ameliorated the carrageenan-induced paw edema and histopathological alterations in db/db mice.