Overexpression Of Sirt3 Promotes High Glucose Attenuated Corneal Epithelial Wound Healing By Regulating Mitophagy Via FOXO3a/PINK1-Parkin Pathway

Purpose To investagate how Sirtuin 3(silent mating type information regulation 2 homolog,Sirt3)promotes high glucose attenuated corneal epithelial wound healing by regulating mitophagy via FOXO3a/PINK1-Parkin Pathway.Methods 1.in vitro The effects of high glucose on Sirt3 expression and the symbolic protide of mitophagy,LC3 B were assessed in Mouse corneal epithelial stem / progenitor cells(TKE2)in treatment of normal glucose(NG,5 m M D-glucose)and high glucose(HG,25 m M D-glucose).An adenovirus was used for overexpression of Sirt3,then observe the influences on migration of TKE2 cells,on FOXO3a(Forkhead box O3)/PINK1-Parkin((PTEN Induced putative kinase protein 1)signal pathway.2.in vivo Establishe diabetic model mice inducing by streptozotocin(STZ).Then assess the expression of endogenous Sirt3 and LC3 B in epithelial between normal and diabetic mice.The corneal epithelial wounded models of normal and diabetic mice were established and administrated with subconjunctival injection of AD-Sirt3.Investigate the effects of exogenous Sirt3 on diabetic mice corneal epithelial repairation and the influences on mitophagy rugulated by FOXO3a/PINK1-Parkin pathway.Results HG induced the downregulation of Sirt3 and the level of mitophagy in TKE2 and corneas from diabetic mice.The results of cell migration assay and corneal wound healing from diabetic mice demonstrated that overexpressing Sirt3 strongly promote wound healing in the presence of HG levels via the upregulation of mitophagy.LC3 B protein,labeling the mitophagy,increased dramatically when the FOXO3a/PINK1-Parkin pathway was activated by Sirt3 overexpression in TKE2 cells,which suggested the mitophagy was involved in the response to cell injury under HG condition in TKE2 cells and corneal wound healing in diabetic miceConclusions Sirt3 promotes corneal epithelial wound healing.The molecular mechanism by which Sirt3 promotes corneal epithelial wound healing was involved in an enhancement of the FOXO3a/PINK1-Parkin pathway through the upregulatiom of mitophagy.This study suggests that Sirt3 plays a protective role in the pathogenesis of diabetic keratopathy.