Protective Effect of Irbesartan by Inhibiting ANGPTL2 Expression in Diabetic Kidney Disease

Angiopoietin-like protein 2(ANGPTL2)stimulates inflammation and is important in the pathogenesis of diabetic kidney disease(DKD).Irbesartan is helpful in reducing diabetes-induced renal damage.In this study,the effects of irbesartan on DKD and its renal protective role involving ANGPTL2 in DKD rats were examined.Wistar rats were divided into normal,DKD,and DKD+irbesartan groups.The DKD+irbesartan group was treated once daily for 8 weeks with 50 mg/kg irbesartan via intragastric gavage.The 24-h urinary albumin was determined each week,renal pathological changes were observed,and expression of ANGPTL2 and nuclear factor-kappa B(NF-κB)in rat renal tissue was assessed by immunohistochemistry.Mouse podocytes cultured in a high concentration of glucose were classified into four groups based on the irbesartan concentrations(0,25,50,and 75ºg/mL).Expression of ANGPTL2 and phosphorylated IκB-αwas assessed by Western blotting.The mRNA levels of ANGPTL2 and monocyte chemotactic protein 1(MCP-1)were assessed by real-time polymerase chain reaction.The DKD rats displayed proteinuria,podocyte injury,and increased ANGPTL2 and NF-κB expression.All were relieved by irbesartan treatment.In podocytes cultured in elevated glucose,ANGPTL2 and phosphorylated IκB-αwere overexpressed at the protein level,and ANGPTL2 and MCP-1 were highly expressed at the mRNA level.Irbesartan down-regulated ANGPTL2 and phosphorylated IκB-αexpression at the protein level and inhibited ANGPTL2 and MCP-1 expression at the mRNA level.The ameliorative effects of irbesartan against DKD involves podocyte protection and suppression of ANGPTL2.