[Diet as a source of hydrogen sulfide and its effects on health and disease].

Initially known for its deleterious health effects, hydrogen sulfide (H2S) has recently been recognized as a biologically important gas carrier, like nitric oxide and carbon monoxide. H2S is produced endogenously in mammalian cells by enzymatic and non-enzymatic pathways. When it is produced by the enzymatic pathway, its synthesis is carried out from the amino acid L-cysteine through the transsulfuration pathway.

Oxidative stress in early metabolic syndrome impairs cardiac RyR2 and SERCA2a activity and modifies the interplay of these proteins during Ca waves.

We investigated how oxidative stress (OS) alters Ca handling in ventricular myocytes in early metabolic syndrome (MetS) in sucrose-fed rats. The effects of -acetyl cysteine (NAC) or dl-Dithiothreitol (DTT) on systolic Ca transients (SCaTs), diastolic Ca sparks (CaS) and Ca waves (CaW), recorded by confocal techniques, and L-type Ca current (I), assessed by whole-cell patch clamp, were evaluated in MetS and Control cells. MetS myocytes exhibited decreased SCaTs and CaS frequency but unaffected CaW propagation.