Beyond Fuel: Exercise-Induced Lactate as a Metabolic-Epigenetic Regulator in Central Nervous System Health and Disease

Lactate, as a pivotal metabolite generated by the body, has attracted considerable attention in numerous biological disciplines in recent years. In addition to its role in supplying energy, lactate also functions as a signaling molecule, with the capacity to mediate a diverse array of physiological effects. Within the central nervous system, lactate is involved in the regulation of critical physiological processes, including neurogenesis, synaptic plasticity, mitochondrial biogenesis, neuroinflammation, and cerebral angiogenesis. Furthermore, lactate has been implicated in the pathogenesis of several central nervous system diseases, such as Alzheimer's disease, stroke, and spinal cord injury, among others. Physical exercise is recognized as a significant neuroprotective strategy; however, further research is required to elucidate the underlying biological mechanisms. In essence, the role of lactate as a metabolic-epigenetic core is gradually becoming a subject of increasing academic interest. The regulatory function of lactate is thought to involve its production (via lactate dehydrogenase), shuttle (via monocarboxylate transporters), sensing (via G protein-coupled receptor 81), and lactylation modifications, among others. This review synthesizes current evidence to elucidate the multifaceted roles of lactate in central nervous system physiology and pathology under exercise regulation, with a view to bridging the gap between molecular mechanisms and therapeutic potential, thereby paving the way for novel strategies in central nervous system disease intervention.