Serum and liver tissue biotinidase enzyme activity in rats which were administrated to valproic acid

Valproic acid (VPA) is an antiepileptic drug widely used and well-tolerated by most of patients. Its non-dose-dependent side effects seen mostly are the temporary gastrointestinal disturbances including anorexia and nausea, and hepatoxicity. As to its dose-dependent side effects are the weight loss, tremor, skin eruption and the alopecia. In this study we aimed to put forward the biotinidase deficiency considered as a possible cause of alopecia in the rats administered with valproic acid, and the correlation between liver and serum biotinidase enzyme activities (BEA) and transaminases, albumin and serum valproic acid levels. In our study, 4 groups of which one of them was a control group, each consisting of 15 male Wistar rats was organized. 200, 400, and 600 mg/kg/day of VPA, and distilled water, two divided doses per day, were administered per orally to VPA-1, VPA-2, VPA-3, and control group, respectively, in 60 days. Their serum and liver biotinidase enzyme activities, serum AST, ALT, albumin, and valproic acid levels were measured. Alopecia was seen in the subjects of 6.6% of VPA-1, 13.3% of VPA-2, and 26.6% of VPA-3. Significant difference in the liver tissues BEA was noted only between VPA-3 and the control group. Reductions were observed both in the liver tissues BEA and the serum BEA levels, which are inversely proportional to the VPA doses. A positive correlation between the liver biotinidase enzyme activities and the serum valproic acid levels, and the negative correlation between the liver tissues biotinidase activities and the serum valproic acid levels were noted, respectively. As a conclusion, the partial alopecia which is an initial symptom of reduced biotinidase activity may also be created depending on the reduction of biotinidase activity during valproic acid therapy. The alopecia which may further be observed in the patients receiving valproic acid therapy may be prevented by means of administration of biotin in a dose of 10 mg/day.