Mitochondrial dysfunction, mitophagy, and role of dynamin-related protein 1 in Alzheimer's disease

Alzheimer's disease (AD) is the most common type of dementia and progressive neurodegenerative disease. The presence of β-amyloid (Aβ) plaques and phosphorylated Tau tangles are considered to be the two main hallmarks of AD. Recent findings have shown that different changes in the structure and dynamics of mitochondria play an important role in AD pathology progression. Mitochondrial changes in AD are expressed as enhanced mitochondrial fragmentation, altered mitochondrial dynamics, and changes in the expression of mitochondrial biogenesis genes in vitro and in vivo models. Therefore, targeting mitochondria and associated mitochondrial proteins seems to be a promising alternative instead of targeting Aβ and Tau in the prevention of Alzheimer's disease. The dynamin-related protein (Drp1) is one such protein that plays an important role in the regulation of mitochondrial division and maintenance of mitochondrial structures. Few researchers have shown that inhibition of Drp1 GTPase activity in neuronal cells rescues excessive mitochondrial fragmentation. In addition, the growing evidence revealed that Drp1 can interact with both Aβ and Tau protein in human brain tissues and mouse models. In this review, we would like to update existing knowledge about various changes in and around mitochondria related to the pathogenesis of Alzheimer's disease, with particular emphasis on mitophagy and autophagy.