Hematoma-driven immuno-epigenetic remodeling after intracerebral hemorrhage: cell-type-specific mechanisms and therapeutic opportunities
Intracerebral hemorrhage (ICH) is a life-threatening subtype of stroke characterized by the acute accumulation of blood within the brain parenchyma and progressive secondary brain injury. After ICH, dysregulated neuroinflammation drives a cascade of secondary injury processes that shape neurological deterioration and long-term recovery. However, the molecular mechanisms that determine the magnitude, temporal evolution, and resolution of immune-inflammatory responses after ICH remain incompletely understood, limiting the development of targeted therapeutic strategies. Accumulating evidence indicates that epigenetic regulation constitutes a critical layer controlling neuroinflammatory programs after ICH. Hematoma-derived stimuli, including hemoglobin degradation products, iron overload, oxidative stress, and damage-associated molecular patterns, create a unique inflammatory microenvironment that reshapes gene-regulatory landscapes in resident and infiltrating cells. DNA methylation remodeling, histone modification dynamics, chromatin accessibility alterations, and non-coding RNA regulatory networks collectively orchestrate cell-type–specific transcriptional reprogramming in microglia, astrocytes, endothelial cells, neurons, and infiltrating leukocytes. Rather than serving as passive consequences of tissue injury, these epigenetic processes actively modulate innate immune activation, cytokine production, leukocyte recruitment, blood–brain barrier integrity, and the balance between neurotoxic and reparative inflammatory states. In this review, we synthesize current evidence on the immuno-epigenetic regulation of neuroinflammation after ICH, with emphasis on cell-specific mechanisms, temporal dynamics, and immune–vascular interactions. We discuss how epigenetic reprogramming contributes to inflammatory amplification, glial phenotypic transitions, endothelial dysfunction, and the potential persistence of maladaptive inflammatory memory. Finally, we highlight emerging precision strategies, including locus-specific epigenome editing and RNA-based therapeutics, that may enable targeted modulation of neuroinflammation after ICH. An immuno-epigenetic perspective may provide a conceptual framework for developing precision neurotherapeutics for ICH.