RESUMO
OBJECTIVES: Tinospora cordifolia (Willd.) Miers is an inevitable ingredient of Ayurvedic rasayanas for the treatment of disorders with unregulated inflammation. However, studies regarding the mechanism of anti-inflammatory potential of this plant at the molecular level are lacking. METHODS: In vitro evaluations were conducted in RAW264.7 macrophages which were preincubated with chloroform extract of T. cordifolia (CETC) and subsequently stimulated with LPS. The expressions of COX-2, TNF-α and iNOS genes were analysed by SQRT-PCR and Western blot, cytokines (IL-6, IL-1ß and PGE2 ) levels by ELISA, NF-κB activation and p38 MAPK phosphorylation by Immunoblot and confocal imaging. Anti-inflammatory potential of CETC was validated further in a rat model of carrageenan-induced hind paw edema. Phytochemical characterisation was carried out using the HPLC technique. KEY FINDINGS: The LPS-induced upregulation of proinflammatory biomarkers was significantly prevented by CETC, without inhibiting COX-1. CETC- and LPS-incubated cells showed reduced phosphorylated p38 MAPK levels, and higher levels NF-κB were retained in cytoplasm. Rats pretreated with CETC showed a statistically significant decrease in paw oedema (P ≤ 0.05), and HPLC characterisation detected stigmasterol and ß-sitosterol. The LD50 of CETC lies above 2000 mg/Kg body weight. CONCLUSIONS: These findings encourage us strongly to focus on CETC to develop anti-inflammatory drugs with lower degree of inhibition to the constitutively expressing COX-1.