VDAC1 Participates OGD/R Injury Induced Cell Death Via Regulating Mitochondrial Membrane Pore Open In R28 Cells

Objective:To explore whether Voltage-dependent anion channel 1（VDAC1）participates Oxygen and glucose deprivation-recovery（OGD/R）injury induced R28 cell death by regulating mitochondrial membrane pore open and its mechanism.Methods:In vitro,R28 cells were subjected to OGD/R injury（2 h）,and then recovered for 0 h,2 h,4 h,6 h,and 8 h,respectively.PI staining and LDH release assay were used to detect necrosis,TUNEL staining and cleaved caspase 3 expression were used to determine cell apoptosis.Mito-tracker Green,JC-1,DHCF-DA and Fluo-3AM marked mitochondrial morphology,mitochondrial membrane potential,intracellular reactive oxygen species（ROS）and intracellular Ca²⁺,respectively,western blot was used to detect CYCS expression change to confirm mitochondrial damage.Western blot was used to detect VDAC1 and its oligomerization form.VBIT-12,a specific inhibitor of VDAC1,was used to further verify the role of VDAC1 in OGD/R-induced R28 cells death.In vivo,SD rats（200～250 g）were selected for acute hight intraocular pressure（a HIOP）treatment.TUNEL staining was used to detect retinal neurons apoptosis.Intravitreal injection of VBIT-12 to inhibit the VDAC1 oligomerization,further to verify the role of VDAC1 in a HIOP induced retinal neurons death.Results:（1）OGD/R injury induced R28 cell death;（2）OGD/R injury induced mitochondrial dysfunction;（3）OGD/R injury increased the expression of VDAC1 and its oligomerization;（4）VBIT-12 effectively inhibited VDAC1 oligomerization and alleviated mitochondrial damage and cell death by reducing mitochondrial membrane pore opening;（5）VBIT-12 alleviated a HIOP injury-induced retinal neurons death in SD rats.Conclusion:After OGD/R injury,the level of VDAC1oligomerization increased in R28 cells,VDAC1 oligomerization leads to the opening of mitochondrial membrane pores,and releases mitochondrial contents which induced R28 cells and retinal neurons death.