Glutathione is a powerful suppoort to the antioxidant system that plays a role in methylation, a process by which methyl groups are added to DNA, RNA, and proteins. This process can affect the expression of genes and can play a role in the development of metabolic misfires
One way in which glutathione is involved in methylation is through its role in the methylation cycle. This cycle is a series of reactions that converts homocysteine to methionine, and then converts methionine to S-adenosylmethionine (SAM). SAM is a methyl donor that is used in many methylation reactions, including the methylation of DNA and proteins.
Additionally, glutathione also can act as a methylation protector by removing toxic methylation intermediates, such as S-adenosylhomocysteine (SAH), which can inhibit methylation reactions.