ObjectiveTo investigate the mechanism of the early kidney injury in rats caused by intermittent hypoxia, and investigate the intervention effect of edaravone.MethodsEighty male Wistar rats were randomly divided into a control group (NC), an intermittent hypoxia group (IH), an intermittent hypoxia edaravone treatment group (IH+NE), and an intermittent hypoxia normal saline matched group (IH+NS). After 4 weeks of model establishment, serum urea nitrogen and creatinine concentration were determined. Pathological changes of kidney were observed under light microscope, and ultrastructural changes of glomeruli and renal tubules were observed under electron microscope. The kidney injury molecule 1 (KIM-1) protein was detected by immunohistochemistry. The levels of superoxide dismutase (SOD), malondialdehyde (MDA), hydroxyl radical and Bcl-2 mRNA, Caspase-3 mRNA, Bax mRNA in homogenate of kidney tissue were measured.ResultsSerum urea nitrogen in each group showed no significant difference. Serum creatinine increased significantly in IH group and significantly decreased after edaravone treatment. There were no significant pathological damages in NC group under light and electron microscopy. IH group showed varying degrees of renal tubule damages compared with NC group. Compared with NC group, the mean optical density of KIM-1 protein in IH group and IH + NS group significantly increased (P<0.01), and the mean optical density of KIM-1 protein in IH+NE group significantly decreased (P<0.01). Compared with NC group, the activity of SOD in IH group and IH+NS group significantly decreased, the content of MDA and hydroxyl radical increased, the expression of Bcl-2 mRNA decreased, the expression of Caspase-3 mRNA and Bax mRNA increased, Bcl-2/Bax?decreased.?After edaravone intervention, the activity?of SOD in?kidney tissue?of rats significantly?increased, the content of MDA and hydroxyl radical?significantly?decreased, the expression?of Bcl-2 mRNA?increased, the expression of Caspase-3 mRNA?and Bax mRNA decreased, Bcl-2/Bax increased.ConclusionsIntermittent hypoxia can cause kidney injury through oxidative stress and regulation of Bcl-2, Bax and Caspase-3. KIM-1 may be used as a sensitive indicator for monitoring early kidney injury. Edaravone can prevent kidney injury induced by intermittent hypoxia though scavenging oxygen free radical, improving antioxidant capacity, regulating cell apoptosis mediated by regulating Bcl-2/Bax and Caspase-3.
