Study on glomerular microvascular injury and repair in patients with IgA nephropathy and its relationship with intermedin

Objective To investigate the glomerular microvascular injury and repair in patients with IgA nephropathy (IgAN) as well as its relationship with intermedin (IMD). Methods Eighty cases of renal tissue taken from patients first diagnosed as IgAN in Shanxi Provincial People's Hospital Affiliated to Shanxi Medical University and 15 cases of normal renal tissue were detected by the expression of glomerular IMD, CD31, and VE-cadherin through immunohistochemical method. ELISA method was used to detect VEGF and IMD of plasm from 31 normal subjects and 36 cases chosen from the IgAN patients. Their changes and internal relationship were analyzed according to Lee's and chronic kidney disease (CKD) classification. Results (1) Compared with the control group the expressions of CD31, IMD, and VE-cadherin in IgAN patients were statistically significant (P＜0.01). Compared with the control group the levels of IMD and VEGF in plasma of IgAN patients in early stage of CKD group and late stage of CKD group were statistically significant (P＜0.01). (2) Correlation analysis: the expression of glomerular CD31 and Lee's classification were negatively correlated (r=-0.232, P＜0.05); glomerular IMD was negatively correlated with Lee's classification (r=-0.241, P＜0.05), while positively correlated with glomerular VE-cadherin (r=0.417, P＜0.01). VEGF in plasma of IgAN patients was positive correlated with CKD classification, BUN (r=0.458, 0.409, P＜0.05), and negatively correlated with serum ALB (r=-0.532, P＜0.01). Conclusion Microvascular injury exists in patients with IgAN. The expression of VE-cadherin and IMD are positively correlated, suggesting that IMD may be involved in the progression of vascular protection and angiogenesis in IgAN. The contents of IMD and VEGF in plasma of IgAN patients increase, indicating that they may play a role in the progression of IgAN.