Protective effect of essential oil of bark on hepatic and renal toxicity induced by carbon tetrachloride in rats.

The inner bark of cinnamon () is widely used as a spice. Cinnamon plants are also a valuable source of essential oil used for medicinal purposes. The present study aimed to investigate the composition and in vitro antioxidant activity of essential oil of bark (CvEO) and its protective effects in vivo on CCl-induced hepatic and renal toxicity in rats. Groups of animals were pretreated for 7 days with CvEO (70 or 100 mg/kg body weight) or received no treatment and on day 7 a single dose of CCl was used to induce oxidative stress. Twenty-four hours after CCl administration, the animals were euthanized. In the untreated group, CCl induced an increase in serum biochemical parameters and triggered oxidative stress in both liver and kidneys. CvEO (100 mg/kg) caused significant reductions in CCl-elevated levels of alanine transaminase, aspartate transaminase, alkaline phosphatase, γ-glutamyl transferase, lactate dehydrogenase, total cholesterol, triglycerides, low-density lipoprotein, urea, and creatinine and increased the level of high-density lipoprotein compared with the untreated group. Moreover, pretreatment with CvEO at doses of 70 and 100 mg/kg before administration of CCl produced significant reductions in thiobarbituric acid reactive substances and protein carbonyl levels in liver and kidney tissues compared with the untreated group. The formation of pathological hepatic and kidney lesions induced by the administration of CCl was strongly prevented by CvEO at a dose of 100 mg/kg. Overall, this study suggests that administration of CvEO has high potential to quench free radicals and alleviate CCl-induced hepatorenal toxicity in rats.