ApoE Expression in Glomerulus and Correlation with Glomerulosclerosis Induced by Adriamycin in Rats

Abstract

Lipid deposition in glomerulus plays an important role in the progression of glomerulosclerosis (GS), and apolipoprotein E (apoE) is an important protein in cholesterol homeostasis. This investigation was performed to explore whether there exists an association between apoE and GS susceptibility. Eighty Wistar rats were randomly divided into two groups: sham operation group and glomerulosclerosis model group, n = 40. The GS disease in rat was induced by uninephrectomy and injecting adriamycin (5 mg/kg) through the tail vein. At the end of 9 and 13 weeks, 20 rats in each group were killed and the relative samples were collected. Serum creatinine, blood urea nitrogen, and 24-h urine protein were determined. Immunohistochemical analysis was performed on renal tissue to detect the expression of apoE, collagen IV, fibronectin, α-smooth muscle actin, and transforming growth factor-β1 in glomerulus. Real-time reverse transcription polymerase chain reaction was conducted to detect the apoE mRNA expression in renal tissue. Compared with sham operation group at the end of 9/13 weeks, glomerulosclerosis model group exhibited levels of serum creatinine, blood urea nitrogen, 24-h urine protein, and a glomerulosclerosis index that were significantly elevated ( p < 0.01), and collagen IV, fibronectin, α-smooth muscle actin, and transforming growth factor-β1 protein expression and apoE expression (protein and mRNA) were significantly upregulated (p < 0.01). In conclusion, apoE can increase the accumulation of extracellular matrix in glomerulus and may take part in the progression of GS.