Definition - What does Gasotransmitter mean?
Gasotransmitters are a group of small gaseous molecules such as NO (Nitric Oxide), H2S (Hydrogen Sulphide), and CO (Carbon Monoxide). Due to high lipid solubility, the molecules can penetrate easily through the cell membrane without requiring significant transporters or receptors. This makes the gasotransmitters responsible for numerous biological functions taking place inside the body at the cellular level, including maintenance of cell metabolism, development, and survival, as well as immunity and vascular biology.
Gasotransmitters do not have to solely depend on the environment for production. In fact, they can also be generated endogenously by particular enzymes. They target specific molecular or cellular sites to exhibit the full potential of their functions.
Safeopedia explains Gasotransmitter
Since the 1977 discovery of the first gasotransmitter, NO, much information is now available about their role and nature. NO was first described by Furchgott, who said that several components caused the stimulation of the endothelium (which resulted in the production of volatile substances). These substances could straightforwardly cause the relaxation of the smooth muscles present in the blood vessels. Hence, it was named as EDRF.
In the mammalian body, NO is produced by an enzymatic reaction that makes use of L-arginase as the primary substrate. NO helps in modulation of the hair cycle, vasodilation, and neurotransmission. It also maintains vessel homeostasis by preventing the growth and contraction of the vascular smooth muscle.
H2S was discovered after both NO and CO. It is produced in mammalian cells by the enzymatic reaction between Cystathionine γ- lyase, Cystathionine β-synthase, and 3-Mercaptopyruvate sulfurtransferase. The primary substrates are homocysteine and L-cysteine. H2S has the smell of rotten eggs and is toxic in nature. It plays the role as an important signaling molecule, owing to its various functions like neuromodulation and neurotransmission. It also helps with learning and memory.
In 1993, the first report was presented that labeled CO as a gasotransmitter. In the human body, CO is produced by heme oxygenase-1and heme oxygenase-2 in heme metabolism. CO acts as a potential therapeutic agent and prevents the adhesion between platelets. It also regulates the functions of the cardiovascular system and performs the role of an important endogenous signaling molecule.
A few recent pieces of research have shown the marked effect of gasotransmitters in the developing oocytes and also in the early embryonic development. The gasotransmitters have additionally been found to be involved in the response to environmental stresses in plants. In grapes, H2S has been found to reduce the post-harvest senescence, which helps in maintaining the firmness in grapes. This protective role of H2S in grapes can be a result of the induction of the antioxidant enzymes that may help to maintain the cell membrane structure. They have also been associated with health, disease, and medicine. Understanding their mechanisms can certainly help in further disclosing their role in medicine.