APP and Alzheimer disease: In a recent study by Dai et al., echinacoside treatment effectively inhibited ER stress in hippocampal neurons of APP/PS1 mice through activating the PERK/eIF2α (protein kinase RNA-like endoplasmic reticulum kinase/eukaryotic translation initiation factor-2α) signalling pathway, indicating that ER stress is a key therapeutic target of echinacoside for AD treatment [53].