AQP4 and early-onset autosomal dominant Alzheimer disease: The study of Wang et al. has confirmed that BHB can antagonize the decrease of SNTA1 expression by inhibiting histone deacetylase 1 (HDAC1) expression and thus restore AQP4 polarity in mice with Alzheimer’s disease, and it was concordant with the results of Wang et al. (2019) and Li et al. (2020).