Contribution of Hydrogen Sulfide to Physiological and Pathological Events and Clinical Use

Hydrogen sulfide (H2S), synthesized by enzymatic or non-enzymatic means, is a third gas neurotransmitter similar to nitric oxide (NO) and carbon monoxide (CO). Enzymes responsible for their synthesis in the body are expressed in various tissues. H2S has many physiological effects such as anti-inflammatory, antiapoptotic, neuroprotective, gastroprotective, antispasmodic, cytoprotective antioxidant, a bronchodilator, blood pressure regulation. Also, it is known that H2S has a role in various pathological conditions such as hypertension, atherosclerosis, depression, asthma, chronic obstructive pulmonary disease (COPD), ulcer, erectile dysfunction, Alzheimer's, and Parkinson's disease. Considering its potential importance in physiopathological conditions, various drugs have been developed in combination with H2S-releasing aspirin and naproxen. In this context, some drugs with anti-inflammatory, analgesic, antioxidant, cytoprotective, and cardioprotective effects have been developed. ATB-346, GIC-1001, NBS-1120, SG-1002, AP-39, and MZe76 are among the candidate drugs. Phase studies of S-zofenopril have been completed. The realization of preclinical and clinical studies on the L-cysteine/H2S pathway is important physiologically, pathologically, and therapeutically, and the development of new drugs in this direction is considered to be promising for treatment approaches.