Basic Science and Pathogenesis.

Background: Mitochondria plays a crucial role at synapses in providing synaptic energy, healthy synaptic function, and cognitive functions. Amyloid-beta and phosphorylated tau protein oligomers cause severe mitochondrial defects in Alzheimer's disease (AD), which leads to the lack of synaptic energy and impaired synapse functions in AD. MicroRNAs (miRNAs) present within the mitochondria are involved in multiple mitochondrial activities and mitochondrial function.