Nitric oxide (NO), a multifunctional gasotransmitter, is now considered an endocrine hormone that essentially contributes to the regulation of glucose and insulin homeostasis. Here, we discuss current genetic data linking NO metabolism to metabolic disorders, especially insulin resistance and type 2 diabetes (T2D). Although several gene variants of NO synthases [NOSs, i.e., neuronal NOS (nNOS), endothelial NOS (eNOS), and inducible NOS (iNOS)] isoforms have been identified in humans that affect NO bioactivity and metabolism, only the eNOS polymorphisms are reported to be associated with insulin resistance and T2D. Among the functional eNOS gene polymorphisms, the single nucleotide polymorphisms (SNPs) rs2070744 (T786C), rs1799983 (G894T), and rs869109213 (eNOS 4b/4a) are related to the risk of developing insulin resistance and T2D.
Keywords: Endothelial Nitric Oxide Synthase, Gene Polymorphisms, Inducible Nitric Oxide Synthase, Insulin Resistance, Neuronal Nitric Oxide Synthase, Nitric Oxide, Type 2 Diabetes.
