Increase of Homocysteinemia/Hydrogen Sulfide (Hcy/H2S) Ratio Raises Cardiovascular Injuries

Increased Homocysteine Levels (HHcy) is an independent risk factor for atherosclerosis. On the other hand, hydrogen sulfide (H2S) exerts a protection against cardiovascular injuries. On the contrary, accumulating evidences showed that downregulation of defective catabolism of HHcy, with reduced H2S synthesis, is involved in the pathogenesis of a variety of cardiovascular diseases. In that occurrence, the detrimental actions on cardiovascular structures performed by HHcy are added to the negative consequences of reduced H2S (in part unlike each HHcy) on cardiovascular system. Therefore, when the reduced re-methylation pathway of Hcy towards Met (resulting in HHcy) is contemporarily added to the decreased trans-sulfuration pathway (inducing a reduction of H2S synthesis) cardiovascular impairment significantly increases.