Traumatic brain injury (TBI) represents a major global public health challenge. It is propelled by a cascade of secondary injuries. These injuries include inflammation, endothelial dysfunction, hypoxia, cerebral edema, and disruption of epigenetic homeostasis. These processes can precipitate necrosis and apoptosis. They also significantly heighten the risk of long-term cognitive deficits, dementia, and other neurodegenerative disorders. TBI progression is typically segmented into acute and chronic phases. Each phase is characterized by distinct pathological mechanisms and epigenetic alterations. The acute phase is dominated by direct tissue damage and robust inflammatory responses. In contrast, chronic TBI often evolves into long-term neurodegenerative conditions like chronic traumatic encephalopathy (CTE). CTE is marked by persistent neuroinflammation and cognitive decline. A critical gap exists in prior research. It lies in the frequent failure to disentangle the unique epigenetic reprogramming specific to each phase. This failure hinders the development of precisely timed interventions. This review systematically delineates the spatiotemporal dynamics of epigenetic regulation following TBI. It aims to construct a phase-specific framework for precision intervention. Acute-phase hallmarks involve DNA methylation. An example is DNMT3A-mediated silencing of homeostatic genes. They also include histone acetylation and m6A RNA methylation. The WTAP/YTHDF1-Lcn2 axis exemplifies this m6A regulation. Conversely, the chronic phase is defined by sustained neuroinflammation, tau hyperphosphorylation, and ferroptosis. These processes are modulated by noncoding RNAs. Examples include miR-29b and lncRNA 4933431K23Rik. Epigenetic drift also plays a regulatory role. Mitochondrial and endoplasmic reticulum stress further interact with these pathways. They amplify secondary damage. We underscore the clinical promise of time-stratified, personalized epigenetic interventions. These interventions aim to improve long-term outcomes. They forge a critical link between fundamental epigenetic discovery and precision management of neurotrauma. This work deepens the understanding of TBI pathophysiology. It also lays a conceptual and target-oriented groundwork. This groundwork advances neurotrauma care into an era of temporally tailored, individualized precision therapy.
Yan et al. (Wed,) studied this question.