Role Of Neutrophil Extracellular Traps In Chronic Kidney Injury Induced By Bisphenol-A

ObjectiveChronic kidney disease(CKD)is a group of kidney diseases characterized by a decrease in glomerular filtration rate,environmental pollutants is one of the risk factors for CKD.Bisphenol-A(BPA)is a common environmental pollutant,According to the report,BPA levels are positively correlated with the proteinuria and impaired renal function.However,its pathological mechanism has not yet been fully elucidated.Neutrophil Extracellular Traps(NETs),which abnormalities in the generation or clearance are associated with multiple kidney injuries.This study aimed to investigate the role of NETs in BPA-induced chronic kidney injury.MethodIn vivo,we treated C57 mice with BPA at 0,5,50,500 ug/kg/day for 8weeks,then collected the serum and kidney tissue in order to detected changes in kidney function and morphology,NETs-related markers such as dDNA,MPO,and citH3 where detected in the whole body and kidneytissue.Subsequently,200 U DNase combine with 500 ug/kg/day BPA were injection twice a week in order to inhibit NETs,? repeat the above indicators to observe whether the kidney injuries is relieved.In vitro,we extracted neutrophils from human peripheral venous blood and stimulated with BPA,extracted the produced NETs to treat podocytes,IF and WB methods were used to detect the expression podocyte marker and skeletal protein.DNase-pretreated NETs treatment were done to observe whether DNase could potect podocytes in vitro.ResultsIn vivo,exposure to BPA results in impaired renal function in C57 mice,confirmed by elevated serum creatinine,blood urea nitrogen,and urinary albumin.renal morphology were also changed,including expansion mesangial matrix and increased renal fibrosis.The structure of the glomerular filtration barrier was destroyed observed electron microscope.At the same time,BPA exposure increased the expression of NETs related markers in C57 mice,including serum dsDNA,and NETs-related proteins MPO and citH3 which were deposited in the kidney.After DNase injection,it was found that BPA exposure-induced renal injury was significantly improved,showing decreased proteinuria,glomerular sclerosis and fibrosis of the kidney.No obviously abnormal in glomerular filtration barrier structure.In vitro,the treat of BPA and/or NETs could cause podocyte injury.The expression of podocyte marker podocin and nephrin is detected by IHC,IF and WB,while the disorder in the cytoskeletal structure were identified by decreased microfimlament marker F-actin.After pretreatment with DNase,the expression of podocyte marker was significantly increased,and no obvious damage was observed in the cell actin.ConclusionNETs were increasing during BPA exposure and participate in BPA-induced chronic kidney injury.