NOS2 and Stroke: The protective effects of estrogen against neuroinflammation are well established in stroke and traumatic brain injury models, where female sex hormones reduce the production of pro-inflammatory cytokines, such as IL-1β, tumor necrosis factor-alpha (TNF-α), inducible nitric oxide synthase (NOS), and nuclear factor kappa B subunit 1 (NF-κB) activation [16].