Hydrogen Sulfide: Physiological and Pathophysiological Functions

Abstract

Hydrogen sulfide (H2S) has been recognized as an endogenous gaseous mediator. The past decade has seen an exponential growth of scientific interest in the physiological and pathological significance of H2S especially with respect to its roles in the central nervous and the cardiovascular systems. In cardiovascular system, H2S regulates heart contractile function and may serve as a cardioprotectant for treating ischemic heart diseases and heart failure. Alterations of the endogenous H2S level have been found in animal models with various pathological conditions such as myocardial ischemia, spontaneous hypertension, and hypoxic pulmonary hypertension. In the central nervous system, H2S facilitates long-term potentiation and regulates intracellular calcium concentration in brain cells. Intriguingly, H2S produces antioxidant, anti-inflammatory, and anti-apoptotic effects that may be of relevance to neurodegenerative disorders. Abnormal generation and metabolism of H2S have been reported in the pathogenesis of ischemic stroke, Alzheimer’s disease, Parkinson’s disease, and recurrent febrile seizure. Exogenously applied H2S is demonstrated to be valuable in the treatment against febrile seizure and Parkinson’s disease. In addition, H2S also regulates the physiological and pathological functions of kidney, pancreas and bone. Exogenously applied H2S may protect against ischemic kidney injuries and osteoporosis. This article surveys the growing recognition of H2S as an endogenous signaling molecule in mammals and its functions in different biological systems. We will emphasize on its physiological and pathological functions in the cardiovascular, central nervous and renal systems.