RESUMO
Arsenic, an environmental pollutant and poisonous metalloid, has adverse effects on different body organs, including the kidneys. Betaine is a natural nutrient that has many beneficial health effects. This research was conducted to examine the impact of betaine on nephrotoxicity caused by inorganic arsenic (NaAsO2) in mice. Mice were separated into following groups: control, NaAsO2 (50 ppm), NaAsO2 (50 ppm) + betaine (500 mg/kg), and betaine (500 mg/kg). Mice were received NaAsO2 via drinking water for 8 consecutive weeks and betaine was given to the animals via gavage once daily in the 7th and 8th weeks of the study. Upon completion of the study, the mice were euthanized and samples of serum and kidney were obtained for further evaluations. Administration of NaAsO2 increased the levels of blood urea nitrogen and creatinine in the serum. It enhanced the amounts of renal malondialdehyde and decreased the total thiol levels, as well as the activity of antioxidant enzymes (catalase, superoxide dismutase, and glutathione peroxidase). Furthermore, it enhanced the levels of renal inflammatory indicators (tumor necrosis factor-alpha and nitric oxide). Western blot results exhibited an increase in the protein expression of nuclear factor kappa B (NF-κB), and phosphorylated NF-κB in NaAsO2-treated mice. Histopathological results also confirmed kidney damage caused by NaAsO2. However, treatment with betaine improved NaAsO2-related kidney injuries in mice. The results of this work indicated that betaine can attenuate kidney damage caused by NaAsO2 by inhibiting oxidative stress and inflammation.
