The effects of caffeine on the renal antioxidant activity in rats

Objective: In our study, the short-term effects of caffeine on the renal antioxidant activity in rats were investigated. Methods: Caffeine was given orally at two different doses: 30 mg/kg and 100 mg/kg (a high non-toxic dose). The current study included 30 rats, which were divided into 3 groups: a control group and two caffeine-treated groups. Group 1 was given caffeine at 30 mg/kg and Group 2 was given caffeine at 100 mg/kg for 14 days. We measured advanced oxidation protein products (AOPP), malondialdehyde (MDA) and nitric oxide (NO) levels in the kidney tissue following caffeine administration. In addition, we also evaluated superoxide dismutase (SOD), and glutathione S transferase (GST) activities in the kidney tissue. Results: Our results showed that caffeine administration decreased lipid peroxidation and advanced oxidation protein products in kidney. Especially, MDA levels in the kidney tissue of the caffeine-treated groups decreased significantly as a result of the dose. NO levels in the kidney tissue of the caffeine-treated groups were higher than those in the control group. GST activities in the kidney tissue of rats in the caffeine groups also increased significantly. In our study, we did not observe significant changes in renal SOD activities upon caffeine consuption. Conclusion: These results show that short-term consumption of two different doses of caffeine may protect against oxidative stress in the kidney tissue of rats. This effect is related to the caffeine dosage. Determining the mechanisms and antioxidant effects of caffeine at suitable dose requires advanced animal and human studies.