Additionally, the accumulation of tau protein is also gaining attention as a significant feature of AD.117 Increased phosphorylation of eIF2α has been observed in postmortem samples from sporadic AD patients and transgenic mouse models.118 In 2016, a study reported that Gastrodin suppressed BACE1 expression in the hippocampi of Tg2576 AD mice under oxidative stress by inhibiting the PKR/eIF2α signaling pathway. Here, BACE1 is linked to Alzheimer disease.