Objective To explore the effect of Osthole on neuroinflammation in Alzheimer's disease(AD)by regulating the lactylation of pyruvate kinase M2(PKM2).Methods(1)Animal experiments:18 mice were divided into three groups,namely wild-type(WT)group,APP/PS1 group and APP/PS1+Osthole group.Learning-and memory-related biobehavioral indicators were compared among the three groups.Immunohistochemistry was used to detect the positive expression of Iba1 in brain tissue,enzyme-linked immunosorbent assay(ELISA)was employed to detect the levels of interleukin(IL)-6,tumor necrosis factor(TNF)-α,and IL-1β in brain tissue,and Western Blot was used to detect the protein expression levels of Pan lactylation(Pan-kla)and PKM2 lactylation(PKM2-kla)in brain tissue.(2)Cell experiments:an in vitro AD model was constructed by treated in mouse microglia(BV2 cells)with LPS/Aβ1-42,and followed by treatment with Osthole.Cell viability was detected by methyl thiazolyl tetrazolium(MTT),expression of Iba1(a marker of microglial activation)was detected by Western Blot,nitric oxide(NO)production was assessed by Griess reagent,and levels of IL-6,TNF-α and IL-1β were detected by ELISA.BV2 cell-conditioned medium(CM)was co-cultured with neuroblastoma cells(Na2 cells)to assess the protective effect of Osthole on Na2 cells.(3)Molecular docking was performed between Osthole and PKM2,and experimental verification was conducted.Results In animal experiments,deficits of learning and memory in mice were aggravated in APP/PS1 group compared with that in WT group,which were improved upon treatment with Osthole.Furthermore,the APP/PS1 group mice showed an increase in Iba1 positive cells in brain tissue,an increase in the levels of pro-inflammatory factors IL-6,TNF-α and IL-1β,as well as an increase in the levels of Pan-kla and PKM2-kla compared with the WT group,while the above indexes were inhibited by the Osthole treatment.In cell experiments,Osthole had no significant effect on BV2 cell viability at concentrations up to 100 μmol/L.Treatment with LPS/Aβ1-42 upregulated the expression of Iba1,NO production,and levels of pro-inflammatory factors IL-6,TNF-α,and IL-1β in BV2 cells,while Osthole significantly inhibited the expression of these LPS/Aβ1-42-induced indicators.Meanwhile,Osthole attenuated the damage of BV2-CM on Na2 cells.The molecular docking results indicated a good binding affinity between Osthole and PKM2.Treatment with Osthole can down-regulated the levels of lactate,Pan-kla and PKM2-kla in the AD cell model.Conclusion Osthole can improve the condition of AD and reduce neuroinflammation by inhibiting the lactylation of PKM2.

Objective To study the role of hydrogen sulfide (H2S) in the effect of SB203580 on proliferation and apoptosis of hepatic stellate cells and the effects of H2S on expressions of collagenⅠand collagenⅢmRNA in hepatic stel-late cells. Methods There were five groups of HSC-T6 cells in this study including control group (DMEM medium contain-ing10%fetal bovine serum), dimethyl sulfoxide (DMSO) group, sodium hydrosulfide (NaHS)group,SB203580 (SB)group and SB+NaHS group. MTT method was used to detect the cell proliferation and inhibition rate of HSC-T6 cells treated by SB203580 and H2S. The apoptotic rate of HSC-T6 cells was detected by flow cytometry with annexin V-FITC/PI double staining. RT-PCR was used to detect the expressions of collagenⅠand collagenⅢmRNA in HSC-T6. Results The apop-totic rate of HSC-T6 cells was significantly higher in SB group and SB+NaHS group than that of control group, and the rate was significantly higher in SB+NaHS group than that of SB group (P＜0.05). There was no significant difference in the apop-totic rate of HSC-T6 cells between DMSO and NaHS groups than that of control group. The expressions of collagenⅠand col-lagenⅢmRNA were found in five groups of cells. There was a higher expression of collagenⅠand collagenⅢmRNA in NaHS group than that of control group (P＜0.05). The expressions of collagenⅠand collagenⅢmRNA were significantly lower in SB group and SB+NaHS group than those of control group and NaHS group (P＜0.05). Conclusion H2S activated P38MAPK signal pathway. And P38MAPK was specifically blocked by SB203580 in HSC-T6 cells, which inhibited the cell proliferation stimulated by H2S and promoted the apoptosis.