Toxicity and Anti-inflammatory Activities of an Extract of the Eleutherine bulbosa Rhizome on Collagen Antibody-induced Arthritis in a Mouse Model

Abstract

As a continuation of our interest in the anti-inflammatory activities of Vietnamese plants, we searched for novel anti-inflammatory agents in Eleutherine bulbosa and evaluated the anti-inflammatory effects of an ethanol extract of the rhizome of E. bulbosa (EBE) on lipopolysaccharide-stimulated RAW 264.7 macrophages in vitro and in a collagen antibody-induced arthritic (CAIA) mouse model in vivo. Treatment of the CAIA mice with EBE decreased the incidence of arthritis, especially at a dose of 1000 mg/kg body weight. A significant (P<0.05) decrease in the arthritis score was seen after high-dose EBE treatment between days 10 and 14 in comparison with the negative control. The serum levels of the inflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, and IL-10 in the mice were measured using commercial ELISA kits. The results suggest that an ethanol extract of the E. bulbosa rhizome has beneficial effects on inflammatory cytokine regulation in an experimental CAIA model.