Regulation of OGD/R-induced inflammatory responses and M1-M2 phenotype switch of BV2 microglia by Lobetyolin

Abstract Objective To evaluate the protective mechanism of Lobetyolin on OGD/R-induced damage in BV2 cells. Methods BV2 cells were pretreated with Lobetyolin, and OGD/R modeling was established using chemical modeling methods to simulate in vivo brain ischemia. The dosage of Lobetyolin and the time and concentration of OGD/R modeling were screened. Changes in cell morphology were observed, and levels of TNF-α, IL-6, iNOS, CD206, and other factors were detected using ELISA. The expression of CKLF1, HIF-1α, TNF-α, CD206, and other proteins was detected using Western Blot. The gene levels of M1 and M2 BV2 markers were analyzed using qPCR. The localization of M1 and M2 BV2 markers was detected using immunofluorescence analysis. Results The study found that Lobetyolin could protect BV2 cells from OGD/R damage. In OGD/R-induced BV2 cells, the protein expression of CKLF1/CCR4 increased, while pretreatment with Lobetyolin reduced this increase. In addition, OGD/R-induced BV2 cells tended to be M1 type, but Lobetyolin could make BV2 cells shift from M1 type to M2 type. Lobetyolin could also reduce the expression of TNF-α, HIF-α and increase the expression of TGF-β protein in BV2 cells, which showed a dose-effect relationship. In the qPCR experiment, Lobetyolin reduced the expression of CD16, CD32, and iNOS at the gene level and increased the expression of CCL-22 and TGF-β. Immunofluorescence analysis showed that Lobetyolin could reduce the expression of CD16/CD32 and increase the expression of CD206. Conclusion Lobetyolin can protect BV2 cells from OGD/R damage by regulating BV2 polarization and reducing inflammatory responses. CKLF1/CCR4 may participate in the process of regulating BV2 cells polarization by Lobetyolin by regulating the HIF-1α pathway.