A study on the effect of Cucurbitacin B on the inflammatory reaction of murine alveolar macrophages induced by lipopolysaccharide / 预防医学

ABSTRACT

Objective To investigate the anti-inflammatory effect of Cucurbitacin B on the inflammatory reaction of murine alveolar macrophages induced by lipopolysaccharide and its molecular mechanism. Methods The alveolar macrophages were randomly divided into five groups blank group, LPS group, different concentrations of Cucurbitacin B (1μM, 2.5μM, 5μM)+) +LPS groups. All group cells were pretreated with different concentrations for 2 h, and followed by 1μg/mL LPS. The protein level of TNF-α, IL-1β, IL-6 and PGE2 were detected by ELISA assay, and the NO was detected by Griess methods, and its upstream protein i-NOS,COX-2, Nrf2 and HO-1 were detected by Western-blot. Results The secretion of TNF-α, IL-1β, IL-6 and PGE2 in LPS group were increased significantly than blank groups, while Cucurbitacin B suppressed its protein level inadose-dependent manner. The nuclear erythroid related factor 2 and antioxidant gene were activated while Cucurbitacin B was added into alveolar macrophages in adose-dependent manner. Conclusion Cucurbitacin B can inhibit the extracellar secretion of inflammatory cytokines production, and its molecular mechanism could be due to the promoting Nrf2 translocation to the nucleus, activating the expression of HO-1 gene, reducing the expression of iNOS and COX-2, and thereby alleviating the inflammatory reaction.