The Relationship Betweenα3β1 Integrin Expression And Podocyte Loss In Diabetic Nephropathy

Objective To investigate the changes ofα3β1 integrin mRNA levels, and the correlation with podocyte loss,microalbuminuria in diabetic rats.Methods An animal model of diabetic nephropathy was induced by intraperitoneal injection of streptozotocin.The rats were sacrificed at week 2,4,6,8,12 after model established.Blood glucose,urea nitrogen,creatinine of blood and urine,urine volume of 24 hours were tested.Wilm's tumor1,microalbumin of urine,renal cortex expression ofα3β1 integrins were examined.Results Compared with the control group, from the second week the podocytes significantly decreased, the urine volume of 24 hours and the microalbuminuria significantly increased, so did the blood urea nitrogen in the fourth week and the blood creatinine in the eighth week.The mRNA levels ofα3β1 integrin obviously decreased from the second week,the mRNA level ofβ1 integrin was the lowest in the twelth week,but the mRNA level ofα3 integrin later didn't decrease any more. The mRNA expression ofα3 integrin correlated positively with the intensity of wilm's tumor1(r=0.782,p<0.01),however,correlated negatively with the amount of urinary albumin per creatinine(r=-0.632,p<0.01); the mRNA expression ofβ1 integrin correlated positively with the intensity of wilm's tumor1(r= 0.574,p<0.01),however, correlated negatively with the amount of urinary albumin per creatinine(r=--0.724,p<0.01).Conclusion The downregulation ofα3β1 integrins in DN may lead to podocyte loss and proteinuria.