Effect of reduced form of coenzyme Q10 on cyclosporine nephrotoxicity.

OBJECTIVES

Cyclosporine, a potent immunosuppressant, has nephrotoxic adverse effects that may be mediated by oxidative stress. The reduced form of coenzyme Q10 has antioxidant effects. The aim of the present study was to evaluate the effect of the reduced form of coenzyme Q10 on cyclosporine nephrotoxicity.

MATERIALS AND

METHODS

Six-week-old male Wistar rats were divided into 3 groups (10 animals each). Group 1 (control) received olive oil only. Group 2 received cyclosporine (30 mg/kg/d, which is an experimentally nephrotoxic dose). Group 3 received cyclosporine (30 mg/kg/d) and the reduced form of coenzyme Q10 (600 mg/kg/d). The cyclosporine and the reduced form of coenzyme Q10 were given orally for 4 weeks. Daily urinary albumin excretion, serum creatinine level, and urinary 8-hydroxydeoxyguanosine level were measured, and renal tissue was evaluated by immunohistochemistry.

RESULTS

In rats treated with cyclosporine and the reduced form of coenzyme Q10 (group 3), there were significantly less abnormalities in mean urinary albumin excretion (group 1: 2.8 ± 0.5; group 2: 41 ± 7; group 3: 21 ± 4 μg/d), serum creatinine (group 1: 1.0 ± 0.2; group 2: 1.8 ± 0.4; group 3: 1.4 ± 0.3 mg/dL), and urine 8-hydroxydeoxyguanosine levels (group 1: 7 ± 3; group 2: 10 ± 3; group 3: 7 ± 1 mg/mL creatinine) than rats treated with cyclosporine alone (group 2). There were 8-hydroxydeoxyguanosine deposits seen in the proximal tubular cells of group 2 that were not present in rats treated with the reduced form of coenzyme Q10 (group 3).

CONCLUSIONS

The reduced form of coenzyme Q10 may prevent or minimize cyclosporine nephrotoxicity by an antioxidant effect.