RESUMO
BACKGROUND: Cyclosporine (CyA) nephrotoxicity is partly due to some oxidative stress. Ubiquinol, the reduced form of coenzyme Q10 (rCoQ10), has recently gained attention for its anti-oxidative potential. The aim of this study is to evaluate the effect of rCoQ10 on a CyA nephrotoxic rat model. MATERIALS AND METHODS: Six-week-old male Wistar rats were divided into three groups (five animals each). Group 1 received a medium only. Group 2 received 30 mg/kg/day of CyA only. Group 3 received both the same dose of CyA and 600 mg/kg/day of rCoQ10. CyA and rCoQ10 were both given orally for four weeks. Systolic blood pressure (BP), daily urinary albumin secretion (u-Alb), serum creatinine (s-Cr) level, and super-oxide anion (SO) level in the renal tissue were measured and compared among those three groups. Immunohistochemistry using an antibody for the transforming growth factor-beta (TGF-beta) was also examined. RESULTS: BPs, u-Albs, s-Crs, and SO levels of groups 1, 2, and 3 were 114 ± 3, 132 ± 4, and 129 ± 5 mmHg, 2.6 ± 0.5, 42.1 ± 7.2, and 22.8 ± 3.4 micro-g/day, 1.1 ± 0.2, 1.7 ± 0.2, and 1.3 ± 0.2 mg/dl, and 224 ± 84, 1251 ± 138, and 512 ± 109 RLU/g kidney respectively. U-Albs, s-Crs, and SO levels were significantly ameliorated by rCoQ10. Micro-vacuolar changes and TGF-beta positive deposits in the proximal renal tubular cells of CyA group rats disappeared in those of CyA and rCoQ10 group rats. CONCLUSION: RCoQ10, an antioxidants, may have potential for preventing CyA nephrotoxicity.