NOS2 and COVID-19: In sepsis (a condition that shares many pathophysiological and clinical features with COVID-19 [60]) the iNOS nitric oxide synthesis is dysregulated with exaggerated production, leading to cardiovascular dysfunction, bioenergetic failure, and cellular toxicity whilst at the same time impaired microvascular function may be driven in part by the reduced nitric oxide synthesis by the endothelium [61].