Rosuvastatin Attenuates Inflammation, Apoptosis and Fibrosis in a Rat Model of Cyclosporine-Induced Nephropathy

Abstract

Background/Aim: Cyclosporine (CsA)-induced kidney injury is characterized by renal dysfunction with inflammatory cell infiltrations, apoptosis and fibrosis. Pleiotropic effects of statins may exert anti-inflammatory, antiapoptotic and antifibrotic actions beyond lipid control. The aim of this study is to investigate whether rosuvastatin (RUS) has anti-inflammatory, antiapoptotic and antifibrotic effects on chronic CsA-induced nephropathy in a rat model. Methods: Male Sprague-Dawley rats fed a low-sodium diet were divided into three treatment groups: control (0.9% saline injection), CsA (15 mg/kg/day by subcutaneous injection), CsA + RUS (10 mg/kg/day by gastric gavage). Renal function, CsA level and lipid levels were measured at the end of 4 weeks. The expression of ED-1, transforming growth factor-β₁ (TGF-β₁) and α-smooth muscle actin (α-SMA) for inflammation and fibrosis were examined by Western blot analysis. The expression levels of apoptosis-associated factors were examined by Western blot analysis. Apoptosis was evaluated using the terminal deoxynucleotidyl transferase-mediated biotin nick end-labeling (TUNEL) method. Results: Kidney function was decreased in CsA-treated rats compared with controls, which was attenuated by RUS. RUS did not affect the lipid level or the blood CsA level. TUNEL staining showed that RUS inhibited CsA-induced tubular apoptosis. RUS decreased CsA-induced increased expression of Bax/Bcl-2 ratio. The expressions of ED-1, α-SMA, TGF-β₁, Smad2/3, Smad4 and p-JNK were increased in CsA-treated rats, which were attenuated by RUS. Tubular atrophy and interstitial fibrosis in CsA-treated rats were attenuated by RUS supplementation. Conclusion: RUS supplementation attenuates proinflammatory and apoptosis-related factors and inhibits the fibrotic pathways including the smad-dependent and smad-independent pathways in a rat model of CsA-induced nephropathy.