NOS2 and Cognitive impairment: The link between aging and neuroinflammation has largely emerged and implicates the aberrant modulation of multiple sets of genes and proteins, such as an increased activation of microglia and astrocytes by both NF-kB and cyclooxygenase-2 (COX2) and inducible nitric oxide synthase (iNOS) levels; this, in turn, induces the release of pro-inflammatory cytokines, leading to neuronal death and subsequent cognitive deficits [51].