APP and Alzheimer disease: In our study, the discrepant reaction of cerebral tau metabolism to low VA diet in C57 and APP/PS1 mice, as indicated by the change of cortical p-tau expression and p-tau/t-tau ratio, suggested that a low VA diet aggravated the dysregulation of the self-protective compensatory mechanism and AD-like phenotype in APP/PS1 mice, further promoting the development of AD8.