Methionine is an aliphatic, sulfur-containing, essential amino acid, and a precursor of
succinyl-CoA, homocysteine, cysteine, creatine, and carnitine. Recent research has …

Elevation of plasma homocysteine level is a risk factor for cardiovascular disease, stroke,
and venous thromboembolism. It is still uncertain, however, whether hyperhomocysteinemia …

Biosynthesis is a necessary process to maintain life. In recent years, research has fully
shown that three kinds of biothiols (Cys, Hcy, GSH) mainly play the role in oxidative stress …

The mitochondrial free radical theory of aging is reviewed. Only two parameters currently
correlate with species longevity in the right sense: the mitochondrial rate of reactive oxygen …

Glutathione (GSH) is a critical endogenous antioxidant found in all eukaryotic cells. Higher
GSH concentrations protect against cellular damage, tissue degeneration, and disease …

Cysteine is considered a nonessential amino acid in mammals as it is synthesized from
methionine via trans-sulfuration. However, premature infants or patients with hepatic failure …

Deficiencies in vitamins or other factors (B6, B12, folic acid, betaine) and genetic disorders
for the metabolism of the non-protein amino acid-homocysteine (Hcy) lead to …

Homocysteine is a sulfur amino acid whose metabolism stands at the intersection of 2
pathways: remethylation, which requires folic acid and B-12 coenzymes, and …

The metabolism of methionine and cysteine in the body tissues determines the
concentrations of several metabolites with various biologic activities, including …

Comparative studies indicate that long-lived mammals have low rates of mitochondrial
reactive oxygen species production (mtROSp) and oxidative damage in their mitochondrial …