Antioxidant Role of Methionine: As an Essential Sulfur-containing Amino Acids

Methionine is one of the essential sulfur-containing amino acids that are used in building proteins. In the body, methionine condenses with ATP to form S-adenosylmethionine (SAM), which acts as a methylation donor in various biological pathways. Methionine is characterized by its antioxidant activity and its ability to modify tissue sensitivity against oxidizing agents. Therefore, this study’s aim included using hydrogen peroxide 0.5% in drinking water to induce oxidative stress in the male rats and testing the ability of different concentrations of methionine for protection or prevention the oxidative stress during 10, 20 and 30 days. Forty male rats with the age of 3-4 months and of weights ranging between 300 to 400 gm were divided into 4 groups: Group (1): control group received drinking tap water, group (2): treated with H2O2 0.5% in drinking water, group (3): treated with H2O2 and methionine 0.3%, group (4): treated with H2O2 and methionine 0.6%. The following parameters in the serum were measured: Vit. C, Vit. E, peroxynitrite, albumin, selenium, zinc, and copper. Treatment with 0.3% methionine produced clear effects on the vit C, peroxynitrite, Zn and Cu levels in the serum, while the treatment with 0.6% methionine produced clear effects on the serum vit E, albumin, and Se levels