Gaseous mediators are chemicals that are produced in small amounts by some cells of the mammalian body and have a number of biological signalling functions. There are three so-far-identified gaseous mediator molecules: nitric oxide (NO), hydrogen sulfide (H2S), and carbon monoxide (CO). [1]
Endogenous gaseous mediators have shown anti-inflammatory and cytoprotective properties [2] Combination nonsteroidal anti-inflammatory drugs featuring both a cyclooxygenase inhibitor and gaseous mediator releasing component are being investigated as a safer alternative to current anti-inflammatory drugs [3] due to their potential reduction in risk for gastrointestinal ulcer formation. [4]
When septic shock occurs in the human body due to bacterial toxins, nitric oxide is released by a variety of cells through the expression of inducible nitric oxide synthase in order to induce vasodilation as part of the inflammatory response. [5] The released nitric oxide can be crucial to the body by reducing instances of platelet and leukocyte adhesion while also counteracting apoptosis. [6] However, prolonged septic shock could lead to the overproduction of nitric oxide, which could lead to cell damage due to nitric oxide radical formation and peroxynitrite (ONOO−) formation after interacting with oxygen in the body. [5] In order to alleviate the toxic effects caused by overproduction of nitric oxide during septic shock, a single high dose (5g IV) of Vitamin B12 has shown the potential to inhibit nitric oxide synthase while acting as a radical scavenger that assists in the elimination of excess nitric oxide produced during prolonged septic shock. [6]