Possible Interaction: Homocysteine and Nitric Oxide

“Furthermore, homocysteine induces endothelial dysfunction by an increased inactivation of nitric oxide.”

“In addition, significant negative correlations were detected between the plasma concentration of nitric oxide and the plasma concentration of homocysteine (r=-0.592, P<0.0001) and ADMA (r=-0.789, P<0.0001).”

“Significant correlations were found between NO and homocysteine and NO and cholesterol.”

“ Homocysteine induced impairment of the endothelium-dependent vasorelaxation of rat aortic rings by isometric tension, while it also reduced the nitric oxide level and the nitric oxide synthase activity in human umbilical vein endothelial cells, followed by accumulation of superoxide anion and cholesterol.”

“Elevated levels of homocysteine also decrease the bioavailability of nitric oxide and modulate the levels of other metabolites including S-adenosyl methionine and S-adenosyl homocysteine which may result in cardiovascular diseases.”

“Moreover, in cultured human umbilical vein endothelial cells, homocysteine increased the synthesis of nitric oxide , an important regulatory molecule for VEGF.”

“Elevated levels of homocysteine also decreases the bioavailability of nitric oxide and modulates the levels of other metabolites including S-adenosyl methionine and S-adenosyl homocysteine which may result in cardiovascular or neurological disorders.”

“Furthermore, homocysteine exposure increased superoxide production and impaired agonist-stimulated nitric oxide release.”

“Other effects of homocysteine include: impaired generation and decreased bioavailability of endothelium-derived relaxing factor/nitric oxide ; interference with many transcription factors and signal transduction; oxidation of low-density lipoproteins; lowering of endothelium-dependent vasodilatation.”

“Taken together, these findings strongly suggest that the adverse vascular effects of homocysteine are at least partly mediated by oxidative inactivation of nitric oxide.”