Ulinastatin Inhibits M1 Polarization Of BV2 Microglia Via Notch/Jagged-1 Signaling

Objective Perioperative neurocognitive disorder is a common complication after surgery and anesthesia.Rencent research suggests that M1 polarization of microglia is relevant to PND.Ulinastatin is a urinary trypsin inhibitor that can inhibit inflammation.It is reported that ulinastatin can effectively reduce the incidence of POCD.However,the mechanism has not been fully elucidated.Therefore,this experiment was planned to use LPS-activated microglia as a neuroinflammation model to investigate the effect of ulinastatin pretreatment on the polarization process of microglia and its molecular mechanism to alleviate PND.Methods LPS(100ng/m L)activated BV2 microglia cell line is used as an neuroinflammation model in vitro.Cells were grouped as following:(1)Control group: use complete medium only;(2)LPS group: treated with medium containing LPS(100ng/m L)for 24h;(3)UTI group: cultured in medium containing different concentrations of Ulinastatin for 2h,and then cultured in medium containing LPS for 24 h to obtain(1)Low-dose UTI group: UTI(10U/ml)+ LPS(100ng/m L)(2)Medium-dose UTI group: UTI(100U/ml)+ LPS(100ng/m L)(3)High-dose UTI group: UTI(1000U/ml)+ LPS(100ng/m L)(4)UTI+Jagged-1 group: cells were cultured in medium containing Ulinastatin(1000U/ml)and Jagged-1(0.5μg/ml)for 2h,and then cultured in medium containing LPS for 24 h.MTT assay was used to detect the effect of ulinastatin on the viability of microglia.Inflammation-related m RNA and partial protein expression levels in BV2 cells were measured by RT-PCR and ELISA.The expression level of Notch signaling pathway proteins were evaluated by Western Blot.Results 1.Ulinastatin less than 1000U/ml is not toxic to LPS activated BV2 cells.2.Compared with the control group,after LPS incubation,the expression levels of TNF-α,IL-1β and i NOS secreted by M1 type BV2 cells increased significantly,and mainly M2 type The expression levels of IL-10 and Arg-1 proteins secreted by BV2 cells did not change significantly.In ulinastatin pretreatment group,TNF-α,IL-1β and i NOS decrease compared with LPS group,while IL-10 increased significantly.3.Compared with the control group,after LPS incubation,the expression of Notch1 and Hes1 proteins in the LPS group alone increased significantly,while the Notch1 and Hes1 protein levels were was not significant changed in cells pretreated with both ulinastatin and Jagged-1 compared with the control group.4.Compared with the group pretreated with Ulinastatin only,the cells pretreated with both Ulinastatin and Jagged-1,expressed more IL-1β and i NOS.Conclusions Ulinastatin can inhibit LPS-induced M1 polarization of BV2 cells through Notch/Jagged-1 signaling pathway...