The Role of Fatty Acids in Neurodegenerative Diseases: Mechanistic Insights and Therapeutic Strategies

Fatty acids (FAs) play multifaceted roles in neurodegenerative diseases (NDDs), including Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). This review systematically summarizes current understanding of fatty acid metabolism and its diverse implications in NDD pathology. Short-chain fatty acids (SCFAs), primarily generated by gut microbiota, regulate neuroinflammation, gut-brain communication, and blood-brain barrier (BBB) integrity via epigenetic modifications and immune modulation. Medium-chain fatty acids (MCFAs) exhibit therapeutic potential by improving energy metabolism and neuromuscular function, particularly in ALS models. Long-chain polyunsaturated fatty acids (PUFAs), notably docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), contribute to neuronal membrane integrity, synaptic plasticity, and antioxidant defense, mitigating oxidative stress and neuroinflammation. Conversely, saturated and certain n-6 fatty acids may exacerbate neurodegeneration through pro-inflammatory and oxidative pathways. Emerging evidence highlights fatty acid involvement in key pathological processes such as lipid peroxidation, mitochondrial dysfunction, ferroptosis, and BBB disruption. Therapeutically, targeted supplementation, dietary modification, microbiome manipulation, and advanced nanotechnology-based delivery systems are promising strategies. Nevertheless, precise therapeutic efficacy depends critically on disease stage, dosage, genetic background, and individual metabolic context. Integrating personalized medicine with precision nutritional strategies and novel drug-delivery platforms offers promising avenues to translate fatty acid-based interventions into clinical practice, potentially improving patient outcomes in the aging global population.