De Novo Design of Potent and Selective Neuronal Nitric Oxide Synthase (nNOS) Inhibitors by a Fragment-Based Approach (original) (raw)

Nitric oxide, a gaseous free radical molecule (NO) behaves, as a secondary messenger in various tissues. It is responsible for different physiological functions and pathological symptoms. Mammals contain three different nitric oxide synthase (NOS) isoforms: neuronal NOS (nNOS: in the brain, in peripheral nervous system and muscle tissues), inducible NOS (iNOS: in macrophage cells), endothelial NOS (eNOS: in endothelial cells). Under certain pathological conditions and/or after certain ages excessive NO produced in brain causes tissue damage and oxidative stress. It also reacts with other free radicals to create specific molecular modifications. The excessive production of NO, especially by nNOS (in brain) is implicated in various disease states such as neurodegeneration, stroke, migraine and Parkinsons, Alzheimers, and Huntingtons diseases. The active sites of three NOS isoforms show great similarity; therefore, designing of selective nNOS inhibitors is not an easy task. The computa...