Interplay Between Aging and Tau Pathology in Alzheimer’s Disease: Mechanisms and Translational Perspectives
Mohammed Alrouji, Mohammed S. Alshammari, Tasqeeruddin Syed, Anas Shamsi
Abstract
Aging is a key risk factor for neurodegenerative disorders and is associated with widespread systemic and brain-specific changes. Alzheimer's disease (AD), a progressive and irreversible brain disorder, primarily affects older adults and leads to a gradual decline in cognitive function. The underlying disease mechanisms often begin years before clinical symptoms appear, limiting the effectiveness of current treatments. Several factors linked to aging-including inflammation, oxidative stress, impaired metabolism, and protein aggregation-contribute to the onset and progression of AD. A central feature of AD is the abnormal accumulation of amyloid beta (Aβ) and tau, a microtubule-associated protein, driven by post-translational modifications such as acetylation and hyperphosphorylation. These modifications lead to structural changes in tau, promoting the formation of neurofibrillary tangles (NFTs), which are more closely associated with cognitive decline than Aβ plaques. Interestingly, tau accumulation and the resulting cognitive impairments are often observed in aged individuals without Aβ deposition, highlighting tauopathy as a distinct contributor to age-related cognitive decline. This review focuses on new developments in therapeutic approaches that target oxidative stress, protein aggregation, and neuroinflammation, and our current understanding of the molecular pathways relating aging and tau pathology in AD.