Exercise training promotes neurogenesis in the adult hippocampus with a particular focus on cell cycle regulation

Adult neurogenesis is predominantly restricted to two neurogenic regions in the mammalian brain: the subventricular zone (SVZ) of the lateral ventricle and the subgranular zone (SGZ) of the dentate gyrus (DG) within the hippocampus. The hippocampus serves as a critical brain structure involved in learning and memory processes, and the continuous generation of new neurons contributes to enhanced synaptic plasticity. Accumulating evidence has demonstrated that impaired hippocampal neurogenesis is closely associated with various neuropsychiatric disorders, including Alzheimer's disease, epilepsy, and traumatic brain injury. Although the precise molecular and cellular mechanisms underlying adult neurogenesis remain incompletely elucidated, extensive research over the past several decades has identified numerous endogenous, exogenous, and environmental factors that modulate this process. Notably, exercise training, as a key exogenous stimulus, has been shown to promote adult hippocampal neurogenesis by influencing the neurochemical environment and functional integration of newly generated neurons. This review aims to summarize the relationship between cell cycle dynamics and adult hippocampal neurogenesis, with a particular emphasis on how physical exercise regulates the cell cycle to activate and promote the proliferation of neural stem cells (NSCs) in the DG, thereby facilitating the differentiation and lineage progression of neural progenitor cells. A deeper understanding of the regulatory mechanisms by which exercise enhances adult hippocampal neurogenesis may provide novel insights into the development of therapeutic strategies for neurological and psychiatric disorders.