Nitric oxide synthase and antioxidant systems (NOS/Antioxidant Pathway)

The Nitric Oxide Synthase (NOS) and Antioxidant Systems represent a complex regulatory network essential for vascular health, neurotransmission, and immune defense (StatPearls). Nitric oxide is synthesized from L-arginine by three distinct NOS isoforms: neuronal (nNOS/NOS1), inducible (iNOS/NOS2), and endothelial (eNOS/NOS3) (UniProt). These enzymes work in tandem with antioxidant systems—comprising enzymes like superoxide dismutase (SOD) and catalase, as well as molecules like glutathione—to maintain redox homeostasis and prevent cellular damage from reactive oxygen species (ROS) (PubMed). When this balance is disrupted, the resulting oxidative and nitrosative stress contributes to the pathogenesis of cardiovascular diseases, neurodegeneration, and chronic inflammation (NIH). Pharmacological intervention typically involves NO donors to treat angina, phosphodiesterase inhibitors to enhance NO signaling, or antioxidant therapies to mitigate tissue injury (PubChem). However, the broad distribution and diverse roles of these components make targeted therapy challenging, often leading to systemic side effects like hypotension or impaired host defense (StatPearls).

Other names

Nitric oxide pathwayRedox signaling systemNOS-ROS axisOxidative stress regulatory pathwayNitric oxide synthase (NOS) isoforms

Drugs targeting this system function by providing exogenous nitric oxide (NO donors), inhibiting specific NOS isoforms to reduce pathological NO production, or enhancing antioxidant capacity to neutralize reactive oxygen and nitrogen species (StatPearls, PubChem).