The Effect of Pioglitazone on the Expression of Transforming Growth Factor (TGF)-β1 and Fibronectin in Diabetic Nephropathy

Background: Peroxisome proliferator-activated receptor (PPAR)- y is a member of the nuclear receptor superfamily. PPAH- r plays an important role in numerous cellular processes including adipogenesis, insulin sensitivity, cell cycle progression, cell differentiation, inflammation, and extracellular matrix production. This study investigated the effect of a PPAR- { agonist on the progression of diabetic nephropathy in OLETF rats. Methods: 30 week-old male OLETF rats were treated for 10 weeks as follows: diabetic control (DM), no treatment: pioglitazone therapy (DM+Pio). LETO rats were used as non-diabetic control (contro]). Body weight, blood pressure, blood sugar, creatinine, total cholesterol, triglyceride, and urinary protein excretion were measured. Histological analysis was taken with light microscope. Glomerular protein and mRNA expression of transforming growth factor (TGF)- fJ 1 and fibronectin were estimated by Western blot and RT-PCR Kidney sections were stained for fibronectin by immunohistochemistry. Results: Serum glucose, triglyceride and urinary protein excretion were decreased in DM+Pio rats compared to DM rats (p