Suppression of Proinflamatroy cytokine gene expression with Aqueous Extract of Berberin

Abstract

Based on knowledge from traditional Iranian herbal medicine, this ex vitro study aims to examine the anti-inflammatory mechanism of Berberis vulgaris L by measuring the expression and release of pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α), cyclooxygenase-1 (COX-1), and interleukine-18 (IL-6), IL-1β and inducible nitric oxide synthase (iNOS) in THP-1. The effects were assessed by measuring the levels of secretory proteins and mRNA of TNF-α and IL-6, the levels of nitric oxide (NO) secretion and the expression of iNOS in THP-1 cells. Cells were treated with 20 ng lipopolysaccharide/ml (LPS) in the presence and absence of concentrations of extracts from the Berberis vulgaris L. During the entire experimental period, we used extract concentrations (0.3 μg/mL) that had no cytotoxic effects, as measured with MTT, MTT and LDH assays. Berberis vulgaris extracts remarkably suppressed the LPS-induced NO release, significantly attenuated the LPS-induced transcription of iNOS and inhibited in a dose-dependent manner the expression and release of TNF-α. significant effects were observed on the release of IL-6. Taken together, these results suggest that Berberis vulgaris probably exerts anti-inflammatory effects through the suppression of TNF-α and iNOS expressions.