NOS2 and nervous system disorder: In particular, HFD causes neuroinflammation through overexpression of proinflammatory cytokines, inducible nitric oxide synthase (iNOS), tumour necrosis factor alpha (TNF-α), as well as through a significant increase of mTOR (mammalian target of rapamycin) activation, which is involved in the pathogenesis of both metabolic and neurological diseases [83,84,85].