MAPT and Alzheimer disease: The great advances have been reported in currently studies of protection against AD by the antioxidant melatonin; this is achieved since melatonin inhibits Aβ-induced toxicity [20, 21, 38, 67, 74, 133] and attenuating tau hyperphosphorylation [14, 45, 54, 56, 118, 119, 121].