Mechanism of action of homocysteine and its thiolactone in hemostasis system.

The disturbance of hemostasis induced by hyperhomocysteinemia; the role of antioxidants.

Elevated concentration of homocysteine (Hcy) in human tissues, definied as hyperhomocysteinemia has been correlated with some diseases, such as cardiovascular, neurodegenerative, and kidney disorders. Homocysteine occurs in human blood plasma in several forms, including the most reactive one, the homocysteine thiolactone (HTL) - a cyclic thioester, which represents up to 0.29% of total plasma H...

Mechanism action of homocysteine and its thiolactone in haemostasis system

Metabolism of homocysteine thiolactone in human cell cultures. Possible mechanism for pathological consequences of elevated homocysteine levels.

Editing of the non-protein amino acid homocysteine, a frequent type of error-correcting process in amino acid selection for protein synthesis by an aminoacyl-tRNA synthetase, results in formation of a cyclic thioester, homocysteine thiolactone. Here it is shown that human cells in which homocysteine metabolism is deregulated by a mutation in the cystathionine beta-synthase gene and/or by an ant...

An in vitro evaluation of the effects of homocysteine thiolactone on key steps of angiogenesis and tumor invasion.

Homocysteine thiolactone is a highly reactive homocysteine derivative that can react easily with proteins. Protein homocysteinylation has been suggested as a possible mechanism underlying the pathological consequences of impaired homocysteine metabolism. Homocysteine inhibits key steps of angiogenesis and tumor invasion. It can be hypothesized that homocysteine thiolactone could mimic the descr...

Calcium-dependent human serum homocysteine thiolactone hydrolase. A protective mechanism against protein N-homocysteinylation.

Homocysteine thiolactone is formed in all cell types studied thus far as a result of editing reactions of some aminoacyl-tRNA synthetases. Because inadvertent reactions of thiolactone with proteins are potentially harmful, the ability to detoxify homocysteine thiolactone is essential for biological integrity. This work shows that a single specific enzyme, present in mammalian but not in avian s...