Endoplasmic reticulum stress promote hepatocyte apoptosis by mediating glycogen synthase kinase 3β / 中华微生物学和免疫学杂志

ABSTRACT

Objective To analyze the role of a key intracellular signaling molecule GSK3β in hepatocyte apoptosis induced by endoplasmic reticulum stress (ERS).Methods Using mouse hepatoma cell lines(Hepa 1) as cell apoptosis model triggered by tunicamycin,an endoplasmic reticulum stress inducer.One hour before Hepa 1 apoptosis induced by tunicamycin,SB216763 specifically inhibited the activity of GSK3β.Living cells/apoptotic cells were detected using acetoxymethyl (AM)/propidium iodide (PI) staining; Furthermore,the measurement of lactate dehydrogenase(LDH) of cell culture supernatant to evaluate the apoptosis.We detect p-GSK3β,GSK3β,the ERS-related protein(GRP78,CHOP and caspase-12) and caspase-3,cleaved caspase-3 protein expression using Western blot.Results Endoplasmic reticulum stress induced by tunicamycin promotes GSK3β activity; Inhibition of GSK3β activity alleviates endoplasmic reticulum stressthe expression of GRP78,CHOP and caspase-12 expression are inhibited.At the same time,GSK3β activity inhibition significantly reduced the endoplasmic reticulum stress-induced apoptosiscompared to cell apoptosis model group,the intervention group of SB216763 showed that the level of LDH decreased significantly,and PI staining of apoptotic cells was also significant reduction.Western blot results showed that the inhibition of GSK 3 β activity reduced reactive cleaved caspase-3 protein.Conclusion GSK3β is an important signaling molecule in the apoptosis pathway induced by endoplasmic reticulum stress ;Endoplasmic reticulum stress promotes hepatocyte apoptosis by mediating GSK3β.