The Study Of The Effect Of SGLT2 Inhibitors In Prevent Contrast-induced Acute Kidney Injury

Research background and purpose:Contrast induced acute kidney injury(CI-AKI)refers to acute kidney injury that occurs after intravascular injection of contrast medium,which is a common complication.The incidence of acute kidney injury caused by contrast medium is about10%,and it is the third cause of new-onset acute kidney injury in hospitalized patients.CI-AKI will increase the adverse outcomes of patients,including increasing the incidence of early or late cardiovascular events,prolonging the length of hospital stay,and increasing the risk of death.Therefore,the prevention and treatment of CI-AKI is worthy of attention.At present,methods such as hydration are often used clinically to prevent contrast medium acute kidney injury,but the existing methods are not satisfactory for the prevention and treatment of contrast medium acute kidney injury,especially in the elderly,hypertension,renal insufficiency and heart failure.Hydration methods commonly used in patients are limited.Acetylcysteine and statins may have some effect,but this conclusion is still controversial.Therefore,we urgently need to find new ways to prevent CI-AKI.At present,it is generally believed that the pathogenesis of CI-AKI is closely related to the toxic effects of contrast agents,changes in renal hemodynamics,oxidative stress,endoplasmic reticulum stress,inflammatory response,and apoptosis,but the mechanism has not yet been clarified.Among them,oxidative stress is at the center of the above mechanisms.Due to its high viscosity and permeability,the contrast agent will change the hemodynamics of the kidney,cause renal ischemia and hypoxia,and prolong its residence time in the kidney.Its toxic effect on cells will lead to Swelling and vacuolation of tubular epithelial cells.The above processes all produce reactive oxygen species,excessive reactive oxygen species can directly damage renal tubular epithelial cells,and can further aggravate renal injury by inhibiting the production of vasodilation substances and inducing apoptosis.Endoplasmic reticulum stress and oxidative stress are closely related to contrast medium-induced acute kidney injury,and the local ischemic stimulation caused by contrast medium in renal tubules interferes with the folding of proteins in the endoplasmic reticulum,causing misfolded proteins to accumulate and bind to the endoplasmic three endoplasmic reticulum stress sensors in the reticulum lumen—inositol requirement enzyme 1,protein kinase RNA-like endoplasmic reticulum kinase,and transcriptional activator 6—competitively bind glucose regulatory protein 78 to trigger the endoplasmic reticulum stress pathway.The endoplasmic reticulum stress pathway can stimulate the release of calcium ions and enter the mitochondria to generate reactive oxygen species,and the excessively generated reactive oxygen species can interfere with protein folding in the endoplasmic reticulum,induce unfolded protein responses,and aggravate endoplasmic reticulum stress.When cells experience irreversible endoplasmic reticulum stress,it will lead to apoptosis of renal tubular epithelial cells and aggravate renal injury.Sodium-glucose cotransporter 2 inhibitors are a new type of oral hypoglycemic drugs,and many studies evaluating the safety and effectiveness of sodium-glucose cotransporter 2 inhibitors,such as the DAPA-CKD study and the CREDENCE study,have confirmed that sodium-glucose cotransporter 2 inhibitors can improve the prognosis of chronic kidney disease in both diabetic and non-diabetic patients.Regulate renal hemodynamic,reduce inflammation and oxidative stress,and improve renal hypoxia.Some early case reports suggested that sodium-glucose cotransporter 2inhibitors may increase the risk of acute kidney injury,but no sodium-glucose cotransporter 2 inhibitors were observed increased the incidence of acute kidney injury in subsequent large phase III clinical trials.In the EMPA-REG study and the DECLARE study,the incidence of acute kidney injury in the empagliflozin treatment group and the dapagliflozin treatment group was lower,and the incidence of acute renal failure in the dapagliflozin treatment group was lower than that in the placebo group.In lipopolysaccharide-induced septic acute kidney injury mice,sodium-glucose cotransporter 2 inhibitors can reverse renal tubular structural damage and inhibit inflammatory responses,oxidative stress and renal tubular cells death in the kidney during septic acute kidney injury,and improved lipopolysaccharide-induced acute kidney injury in sepsis.Both in vitro and in vivo experiments prove,sodium-glucose cotransporter 2 inhibitors can inhibit endoplasmic reticulum stress through the elf2α-ATF4-CHOP pathway,reduce proximal tubular epithelial cell apoptosis,and attenuate renal injury.Previous studies have confirmed that sodium-glucose cotransporter 2 inhibitors have a protective effect in some acute kidney injuries,but their role in CI-AKI is still unclear.Therefore,this study intends to use C57BL/6J mice as the experimental objects to construct a CI-AKI model that conforms to clinicopathological characteristics,and to pre-intervene with sodium-glucose cotransporter 2 inhibitor Dapagliflozin to explore the specific role and mechanism of glucose cotransporter 2 inhibitors in the prevention of CI-AKI,in order to provide an experimental basis for finding new ways to prevent CI-AKI in clinic.Materials and Methods:Thirty-six mice(SPF grade,male,wild type,6-8 weeks old,C57BL/6J)were randomly divided into 6 groups,6 mice in each group.They were control group(Control),contrast induced acute kidney injury(CI-AKI),vehicle group(Vehicle),and dapagliflozin intervention group: low dose dapagliflozin group(LD+CI-AKI),medium dose dapagliflozin group(MD+CI-AKI),and high dose dapagliflozin group(HD+CI-AKI).The CI-AKI model was constructed by intraperitoneally injecting indomethacin and nitroso-L-arginine methyl ester sequentially after 24 hours of water deprivation,and then injecting iodixanol.The vehicle group was treated with the same amount of solvent before modeling intervention;the Dapagliflozin intervention group was given low,medium and high doses of Dapagliflozin by intragastric administration 2hour before modeling.Blood and kidney samples were taken 24 hours after the intervention,and serum creatinine,creatinine clearance rate,blood urea nitrogen,renal pathological changes,oxidative stress levels,endoplasmic reticulum stress levels,and cell apoptosis were observed in each group of mice.Result:1.Compared with the CI-AKI group,the serum creatinine concentration and blood urea nitrogen concentration of each group in the dapagliflozin intervention group were significantly decreased(P<0.001),and the creatinine clearance rate was significantly increased(P<0.001),The concentration of kim-1 molecules was significantly reduced(P<0.001);the pathological damage of kidneys was alleviated,and the scores of renal tubular damage were significantly reduced(P<0.001).2.Compared with the CI-AKI group,the apoptotic cells in the kidney tissue of each group in the dapagliflozin intervention group were significantly reduced,and the positive rate of TUNEL cells was significantly reduced(P<0.001),and the expression level of Cleaved-Casepase3 protein in the kidney tissue comparable to Casepase3 protein expression level decreased significantly(P<0.001),and the ratio of Bcl-2protein content to Bax protein content increased significantly(P<0.05).3.Compared with the CI-AKI group,the levels of ROS and MDA in each group of Dapagliflozin intervention group were significantly decreased(P<0.001),and the content of MDA was significantly decreased(P<0.001).Nrf2 and HO-1 protein The expression levels were significantly decreased(P<0.001).4.Compared with the CI-AKI group,the GSH concentration and SOD activity in the serum and kidney tissue of each group in the dapagliflozin intervention group were significantly increased(P<0.001).5.Compared with the CI-AKI group,the damage and expansion of the endoplasmic reticulum in the kidney tissue of each group in the dapagliflozin intervention group were significantly reduced,and the protein expressions of ATF6 and XBP-1 were significantly reduced(P< 0.001).Conclusion:1.Dapagliflozin intervention improved the renal function decline caused by the contrast medium;alleviated the renal histopathological damage caused by the contrast medium;alleviated the apoptosis of renal tissue cells caused by the contrast medium.2.Dapagliflozin intervention inhibited the increase of ROS level in kidney tissue caused by contrast medium,reduced the concentration of MDA in serum and kidney tissue,reduced the expression of Nrf2 and HO-1 in kidney tissue,and Increase the SOD activity and GSH concentration in serum and kidney tissue,improve the level of oxidative stress in kidney tissue.3.The intervention of dapagliflozin inhibited the structural damage of endoplasmic reticulum in kidney tissue caused by contrast medium,reduced the expression of ATF6 and XBP-1 proteins in kidney tissue,and improved the level of endoplasmic reticulum stress in kidney tissue.