Abstract 278: Enhanced Cystathionine ß-Synthase Nitration in Diet-Induced Hyperhomocysteinemic Rats Accelerates the Progression of Hyperhomocysteinemia

Hyperhomocysteinemia is an independent risk factor for cardiovascular diseases,which may be caused by genetic deficiencies in enzymes responsible for remethylation or transsulfuration of homocysteine, nutritional deficiencies in vitamins, or excessive intakes of methionine. Since transsulfuration pathway is the only irreversible pathway in homocysteine metabolism, its key enzyme cystathionine β-synthase is vital in terminal removement of homocysteine. In addition, Studies have observed that enhanced nitrative stress in hyperhomocysteinemic rats could induce cardiovascular injuries, and peroxynitrite stimulation in vitro resulting in decreased bioactivity of cystathionine β-synthase. Therefore, to determine the contribution of nitrative stress to progression of hyperhomocysteinemia, and how it is related to cystathionine β-synthase, we used three groups of rats (Con with normal diet, HHcy with 2.5% methionine diet, HHcy+FeTMPyP with 2.5% methionine diet +FeTMPyP) to observe the effects of nitrative stress ...