Abstract
Aging is the greatest risk factor for Alzheimer's disease (AD), but the mechanisms connecting the two remain unclear. The mammalian target of rapamycin (mTOR) pathway, particularly its downstream effector S6 kinase 1 (S6K1), has emerged as a key regulator of aging and neurodegeneration. S6K1 controls translation, autophagy, and mitochondrial function-processes disrupted in both aging and AD. This review examines how S6K1 influences mitochondrial metabolism, autophagy, and metabolic dysfunction in aging. We also discuss its role in the nervous system, including effects on synaptic plasticity, memory, glial activation, and neuroinflammation. In AD, S6K1 contributes to amyloid and tau pathology by regulating translation of BACE1 and tau, and its hyperactivation is linked to synaptic deficits and cognitive decline. We further explore therapeutic strategies targeting S6K1, which have shown benefits for lifespan extension and neuroprotection in preclinical models. Finally, we consider the emerging link between S6K1 and necroptosis, a form of programmed cell death implicated in AD-related neuronal loss. Together, these findings highlight S6K1 as a promising target for interventions aimed at slowing aging and mitigating AD pathogenesis.