Additive antifibrotic effects of pioglitazone and candesartan on experimental renal fibrosis in mice

Aim: To examine the additive protective effects of the peroxisome proliferator-activated receptor-gamma agonist pioglitazone (Pio) and the angiotensin II receptor blocker candesartan (Cand) in a murine model of renal fibrosis: mice with unilateral ureteral obstruction (UUO). Methods: Mice were randomly assigned into four groups that after UUO received i.p. injections of either Pio (10 mg/kg/day), Cand (1 mg/kg/day), Cand + Pio or vehicle for 10 days. Physiological parameters, the degree of renal fibrosis and molecules related to renal fibrosis were analysed, and sham-operated mice were used as controls. Results: Total collagen assay showed prominent renal fibrosis in the vehicle-treated mice, significantly attenuated renal fibrosis in the Cand-treated and the Pio-treated mice, and further attenuated renal fibrosis in the (Cand + Pio)-treated mice. Real-time reverse transcription polymerase chain reaction revealed that this attenuation pattern was also evident in the expression of the mRNA for transforming growth factor-beta, collagens I and III, and plasminogen activator inhibitor-1. Conclusion: Pioglitazone and candesartan have additive protective effects on renal fibrosis due to UUO in mice, suggesting that their use in combination would be an effective treatment for chronic kidney disease.