Histopathological nephrotoxic features of high oral doses of ubiquinone in rats

Co-enzyme Q10 (Co-Q10) plays a key role in the cellular respiration for the production of ATP. The toxicity of quinones to the kidney appears to depend on variety of factors, including genetic polymorphisms and the individual’s comorbidites. The aim of the present study was to assess histologically the nephrotoxic effects of 6 weeks daily oral intake of Co-Q10 in experimental animals.

Twenty-five Wistar rats weighing between 220-270 g were randomly divided into two groups: experimental “treated” and control “untreated” groups (n=15, n=10, respectively). The animals of the experimental group received 300 mg/kg daily dose of gelatinous capsules of Co-Q10 by oral gavage for six weeks. At the end of the study, all animals were sacrificed under general anesthesia and samples of the kidneys were excised for microscopic histopathological assessment of renal tissue using stain. The experimental group showed a range of mild to severe dilatation of Bowman’s space, with a mean corpuscular diameter of 294±38 µm that was significantly higher (p <0.05) than that of the untreated control group 208±31 µm. Shrinkage to complete destruction of the glomeruli was observed in the experimental group only. The long-term use of high doses of Co-Q10 had revealed a selective nephrotoxicity towards podocytes. This might be a risk factor leading to renal proximal tubular necrosis in rats and the subsequent renal function deterioration.