Protective effect of remote ischemic preconditioning separating medium on hypoxic injury of human renal tubular epithelial cells
Objective:To investigate the effect and mechanism of remote ischemic preconditioning(RIPC)separa-ting medium on hypoxia/reoxygenation(H/R)injury of human renal tubular epithelial cells(HK-2).Methods:HK-2 cells were divided into time control group,H/R,RIPC treatment group and autophagy intervention group.Cells in the time control group were cultured under normal conditions.Cells in the RIPC group were pretreated with RIPC separa-ting medium.Cells in the autophagy intervention group were treated with autophagy inhibitor 3-methyladenine(3MA)on the basis of RIPC treatment.Cells in the latter three groups were subjected to H/R in a three-gas incubator to con-struct a damage model.After the success of the model,the cell status of each group was observed by optical microscope,and the expression levels of LC3Ⅱ/Ⅰprotein and Beclin1 protein were observed by Western blot.Results:Under the microscope,RIPC separating medium could significantly reduce the damage of H/R to HK-2 cells.After adding auto-phagy inhibitor,the protective effect of RIPC separating medium on H/R injury of HK-2 cells was blocked.The results of Western blot showed that RIPC separating medium could increase the expression levels of autophagy-specific proteins LC3Ⅱ/Ⅰand Beclin1 in mitochondria of HK-2 cells.The results of Real-time PCR showed that the mRNA expres-sion of LC3 and Beclin1 in RIPC group was significantly higher than that in H/R group;the expression of autophagy-specific proteins LC3Ⅱ/Ⅰand Beclin1 in mitochondria of HK-2 cells was decreased by adding autophagy inhibitors,and the mRNA expression of LC3 and Beclin1 was also significantly decreased.Conclusion:RIPC separating medium has a protective effect on HK-2 cells after H/R injury,and the mechanism may be related to mitophagy.