Endogenous SO2 Controls Cell Apoptosis: The State-of-the-Art

Abstract

SO2, previously known as the product of industrial waste, has recently been proven to be a novel gasotransmitter in the cardiovascular system. It is endogenously produced from the metabolism pathway of sulfur-containing amino acids in mammalians. Endogenous SO2 acts as an important controller in the regulation of many biological processes including cardiovascular physiological and pathophysiological events. Recently, the studies on the regulatory effect of endogenous SO2 on cell apoptosis and its pathophysiological significance have attracted great attention. Endogenous SO2 can regulate the apoptosis of vascular smooth muscle cells, endothelial cells, cardiomyocytes, neuron, alveolar macrophages, polymorphonuclear neutrophils and retinal photoreceptor cells, which might be involved in the pathogenesis of hypertension, pulmonary hypertension, myocardial injury, brain injury, acute lung injury, and retinal disease. Therefore, in the present study, we described the current findings on how endogenous SO2 is generated and metabolized, and we summarized its regulatory effects on cell apoptosis, underlying mechanisms, and pathophysiological relevance.

Gaseous signal molecule SO2 regulates autophagy through PI3K/AKT pathway inhibits cardiomyocyte apoptosis and improves myocardial fibrosis in rats with type II diabetes

“…With further research on endogenous SO 2 , the physiological protective effect of SO 2 in the body has been gradually revealed. SO 2 has been considered the fourth endogenous gas signal molecule newly discovered after NO, CO, and H 2 S. It exhibits the functions of vasodilator, anti-oxidation, anti-inflammatory, inhibition of apoptosis, and smooth muscle proliferation while having an important protective effect on the cardiovascular system at a proper concentration [ 30 , 53 - 55 ]. However, the correlation between SO 2 and myocardial fibrosis and remodeling remains unclear, and the internal regulatory mechanism is unknown [ 56 ].…”

Image‐guided diagnosis and treatment of glioblastoma

“…SO 2 is a messenger molecule of physiological process, 125 which is expected to treat tumors by inducing oxidative stress and inhibiting protein expression. 126 In 2022, Liu et al prepared dye-sensitized up/down-conversion luminescence NaYf4:Yb/Tm@NaYF4:Nd nanoparticles for NIR-II imaging and SO 2 gas therapy of orthotopic GBM.…”

A Whiff of Sulfur: One Wind a Day Keeps the Doctor Away

“…Furthermore, endogenous SO 2 is closely linked with the pathogenesis of blinding retinal disease since the downregulation of endogenous SO 2 has been reported to result in increased apoptosis of 661w retinal photoreceptor cells [ 69 ]. Then again, in the respiratory system, endogenous SO 2 has been reported to assist the apoptosis of polymorphonuclear neutrophils (PMNs) and to inhibit the apoptosis of alveolar macrophages in order to provide protection against acute lung injury [ 63 , 70 ]. In any case, the relationship between SO 2 and apoptosis is complicated, often dependent upon its exact concentration and the cell type exposed to it, and clearly requires further investigation.…”

“… In humans, SO 2 is produced from L-cysteine and metabolized to SO 3 2− and SO 4 2− , which are excreted via the urine. A brief list of biological activities is provided and more details can be found in the text [ 62 , 63 , 64 ]. …”