Malibatol A Enhances Alternative Activation Of Microglia By Inhibiting Phosphorylation Of Mammalian Ste20-like Kinasel In OGD-BV-2 Cells

Purpose:To investigate the polarization effect of Malibatol A on oxygen-glucose deprivation (OGD)-BV-2 cells, and the possible molecular mechanism involved in c-Abl-MST signaling pathway.Methods:The OGD BV-2 cell model was established. BV-2 cells were exposed to OGD 8h followed reperfusion 24h with Malibatol A at different concentration of 0.5, 1,2,4,8,16μM or without it. And then cells, mRNA and protein were harvested respectively. The cell viability and apoptosis were measured by MTT assay and flow cytometry. The mRNA of classical activated microglia (M1) markers (MCP-1, IL-1 and TNF-a) and alternatively activated microglia (M2) markers (Ym-1, CD206 and TGF-β) in BV-2 cells were measured by RT-PCR. Meanwhile, the protein of Ym-1 and CD206 were assayed by flow cytometry. Furthermore, the expression of c-Abl and MST were measured by Western blot.Results:Malibatol A significantly decreased apoptosis and increased viability of OGD BV-2 cells in a dose-dependent manner. At the presence of Malibatol A, the mRNA level of Ym-1, CD206,IL-10 and TGF-β mRNA were significantly increased in OGD-BV-2 cells, while the mRNA level of MCP-1, IL-1 and TNF-a were obviously down-regulated. Meanwhile, the protein of Ym-1 and CD206 were raised in OGD BV-2 cells with Malibatol A. Besides, Malibatol A also inhibited OGD-induced p-MST1(Y433) in BV-2 cells.Conclusions:Malibatol A could attenuate OGD-induced BV-2 cell injury and promote M2 microglia polarization. The mechanism may be related to inhibition of MST1 phosphorylation at Y433.