VDR and Alzheimer disease: This result suggested that the Aβ42 impairment of the VDR/RXR pathway was not rescued by vitamin D. Because our previous work had demonstrated that Aβ42 switched VDR binding partner from RXR to p53 to transduce the non‐genomic vitamin D signal in AD brain (Lai et al., 2021), we wanted to investigate whether the VDR/p53 complex formation was enhanced by vitamin D. We performed co‐immunoprecipitation assays and found that the Aβ‐triggered VDR/p53 complex was indeed further enhanced by the treatment of vitamin D3 (Figure 2b).