Microgliamediated neuroinflammation in intracerebral hemorrhage: Pathological mechanisms and implications for

Xuehui Fan1, Changzhi Pu2, Luyi Zhong1

  • 1Key Laboratory of Medical Electrophysiology, Ministry of Education and Medical Electrophysiological Key Laboratory of Sichuan, Collaborative Innovation Center for Prevention of Cardiovascular Diseases, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, Sichuan 646000, P.R. China.

Intracerebral hemorrhage (ICH), a life‑threatening subtype of stroke accounting for 10‑15% of global stroke cases, is characterized by high disability and mortality rates, imposing a heavy socioeconomic burden worldwide. Despite its clinical importance, no effective therapeutic interventions exist for this condition. As the resident immune cells of the central nervous system, microglia play a pivotal role in the pathophysiology of ICH. These cells can be activated to adopt either anti‑inflammatory or pro‑inflammatory phenotypes. Following ICH, pro‑inflammatory mediators derived from microglia act as key drivers of neuroinflammation, thereby exacerbating secondary brain injury. By contrast, promoting the phenotypic shift of microglia toward an anti‑inflammatory state has been shown to mitigate an inflammatory response and facilitate neurological recovery. In the present study, existing evidence was reviewed to propose that post‑ICH brain injury and repair are orchestrated not by isolated cells, but by a highly dynamic neuroimmune network centered on microglia. Elucidating the spatiotemporal dynamics and key communicative nodes within this network represents a critical frontier. Moving beyond the classical M1/M2 dichotomy to target this network contextually offers a promising and precise therapeutic aim for future investigations.

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