Fig. 1

Alzheimer’s disease and neuronal apoptosis. Apoptosis is conducted through intrinsic and extrinsic pathways in the pathogenesis of Alzheimer’s disease. Inflammatory cytokines, such as TNFα, IL-6 and IL-1β, can trigger the neuronal apoptosis through membrane receptor or extrinsic pathway (i.e., TNFα/caspase-8/caspase-3). The intrinsic pathway of neuronal apoptosis is activated by intracellular insults including tau aggregates, mitochondrial dysfunction, endoplasmic reticulum (ER) stress, free radicals, etc. Mitochondrial cytochrome c (Cyt c) is released to initiate apoptosis signaling through the Cyto c/caspase-9/caspase-3 cascade. The pathological manifestations of Alzheimer’s disease depend on the comprehensive effect of diverse mechanisms. There is a complicated network to modulate the development of Alzheimer’s disease. The red line represents inhibitory effect. Bcl-2, B-cell lymphoma 2; IL-1β, interleukin-1β; ROS, reactive oxygen species