Bioenergetics and lipid metabolism in Alzheimer's disease: From cell biology to systemic health.

Alzheimer's disease (AD) is a complex neurodegenerative disorder characterized by progressive cognitive decline. Although amyloid-β and tau pathologies remain central to our understanding of AD, growing evidence suggests that disrupted lipid metabolism and impaired bioenergetics are closely linked to these hallmark features. Genetic, lipidomic and functional studies point to alterations in cholesterol, phospholipids and polyunsaturated fatty acids, which can influence mitochondrial function, organelle communication and glial responses. These processes are further modulated by apolipoprotein E (APOE) genotype, sex differences and systemic metabolic states such as obesity and diabetes, contributing to neuroinflammation and cognitive decline. Although findings are sometimes conflicting, an emerging theme is that lipid and energy metabolisms are central to how genetic and environmental risk factors shape AD pathogenesis. This integrated perspective highlights lipid and bioenergetic pathways as promising therapeutic targets, where metabolic modulators, lipid-directed interventions and lifestyle strategies may complement amyloid-based therapies and offer opportunities for precision approaches, particularly in women and APOE ε4 carriers.