Correlations of podocyte injury with glucose regulated protein 78 expression and proteinuria in patients with diabetic nephropathy.

OBJECTIVE: To explore the podocyte injury in patients with diabetic nephropathy (DN) and analyze its relationship with glucose regulated protein 78 (GRP78) and proteinuria. METHODS: The clinical data of 48 patients diagnosed as DN by renal biopsy were reviewed. All patients were divided into two groups according to proteinuria (>3.5 g/d, n=31 and 3.5 g/d, n=17). The density of podocytes was illustrated by immunohistochemistry staining of Wilms tumor-1 (WT-1), and the immunofluorescence double-staining results of synaptopodin and GRP78 in podocytes were detected. RESULTS: The podocyte dentistry of urine protein > 3.5 g/d group was significantly lower than that of urine protein>3.5 g/d group urine protein<3.5 g/d group(P=0.003), and it was negatively correlated with proteinuria (P=0.005). The expressions of synaptopodin and GRP78 in podocytes were also negatively correlated with proteinuria (P=0.004 and P=0.001). CONCLUSION: The podocyte injury is aggravated with increased proteinuria in DN patients, along with the decrease of the adaptive ability of endoplasmic reticulum to stress.