With regard to AD, pre-clinical and clinical trials have shown that EGCG can act at different steps, such inhibiting TAU aggregation, reducing Aβ accumulation, suppressing tumor necrosis factor α (TNFα), inducible nitric oxide synthase (iNOS) or interleukin 6 (IL-6) expression, or even protecting mitochondrial function [[19], [20], [21], [22]]. Here, NOS2 is linked to Alzheimer disease.