AKAP1 Alleviates Renal Ischemia-reperfusion Injury By Inhibiting Mitochondria Division

Background In recent years,the incidence and mortality of acute kidney injury have gradually increased,and its prognosis is poor,and it is easy to progress to chronic kidney disease or even end-stage renal disease,which has become a global public health problem.Objective Renal ischemia-reperfusion injury is one of the main causes of acute kidney injury.This study aims to explore the role of A Kinase Anchor Protein 1(AKAP1)in renal ischemia-reperfusion injury and its mechanism through classic ischemia-reperfusion injuryinduced AKI model.To provide a potential intervention target for clinical prevention and treatment of AKI.Methods(1)In vivo:In this study,20 SPF male C57BL/6(20-25 g)mice were randomly divided into sham group and IRI group.Bilateral renal arteries were clipped for 28 min of ischemia and 48 h of reperfusion to establish mouse IRI model.Renal function was assessed by measuring creatinine and urea nitrogen,the pathological results of kidney were observed by HE staining,the expression of AKAP1 was detected by immunohistochemical staining,western blot analysis and real-time fluorescence quantitative PCR.(2)In vitro:Proximal renal tubular epithelial cells(m PTC)were cultured and randomly divided into 6 groups: Blank control group(control group),hypoxia and reoxygenation group(H/R group),pc DNA3.1+control group,pc DNA 3.1+H/R group,pc DNA 3.1-AKAP1+control group,pc DNA3.1-AKAP1+H/R group.The H/R model was established by Anning anoxic packet,and the transfection was observed by fluorescence microscope.The expressions of AKAP1 and Drp1Ser637 were detected by western blotting and real-time quantitative PCR.Mitochondrial membrane potential was detected by JC-1 staining,ATP content was determined by ATP detection kit,and mitochondrial morphology was observed by plasmid transfection with MitoRed.Results(1)After successful establishment of mouse IRI model,AKAP1 expression decreased after renal ischemia-reperfusion injury.(2)Decreased AKAP1 expression and mitochondrial dysfunction were observed in mouse renal tubular epithelial cells after hypoxia and reoxygenation.(3)AKAP1 was successfully overexpressed by plasmid transfection in m PTC cells.(4)AKAP1 overexpression inhibited the mitochondrial dysfunction of renal tubular epithelial cells induced by lack of reoxygenation.(5)Mitochondrial division can be alleviated by regulating Drp1 after AKAP1 overexpression.Conclusion AKAP1 expression decreased after renal ischemia reperfusion injury in vitro and in vivo,accompanied by mitochondrial dysfunction.Overexpression of AKAP1 alleviates mitochondrial division by reducing Drp1 Ser637 dephosphorylation.In conclusion,AKAP1 can reduce renal ischemia-reperfusion injury by inhibiting mitochondrial dysfunction.