[Resveratrol reduces apoptosis of mouse RAW264.7 macrophage via down-regulating HIF-1α]

Objective To investigate the protective effect of resveratrol (Res) against mouse RAW264.7 macrophage injury induced by cobalt chloride (CoCl₂) and its mechanism. Methods Macrophages were divided into control group, CoCl₂ group and Res pretreatment group. CoCl₂ group was treated with 500 μmol/L CoCl₂ for 8 hours, and Res pretreatment group was pretreated with 40 μmol/L Res for 2 hours followed by 500 μmol/L CoCl₂ treatment for 8 hours. The cell vitality and apoptotic rate in every group were detected by CCK-8 assay and flow cytometry. The distributions of caspase-3 and hypoxia-inducible factor 1 alpha (HIF-1α), as well as the influences of CoCl₂ and Res on their expression were detected by immunofluorescence cytochemistry. The levels of superoxide dismutase (SOD) and malondialdehyde (MDA) in every group were measured by the corresponding kits. The expression levels of Bcl2, BAX, c-caspase-3 and HIF-1α in every group were observed by Western blot analysis. Results Compared with the CoCl₂ group, pretreatment with Res increased cell vitality, decreased apoptosis, enhanced the activity of SOD, and reduced the level of MDA. The caspase-3 was mainly distributed in the cytoplasm, and HIF-1α was mainly distributed on the nucleus. Compared with the CoCl₂ group, Res up-regulated the expression of Bcl2 and down-regulated the expression of BAX, cleaved caspase-3 and HIF-1α. Conclusion Res can decrease apoptosis in macrophages, which may occur via reducing the accumulation of intracellular reactive oxygen species, enhancing cell antioxidant capacity, and down-regulating the expression of HIF-1α on cells.