Researchers from Kansas City University School of Medicine published a scoping review on Jul. 14 examining the role of astrocytes in chronic traumatic encephalopathy (CTE). The review synthesizes evidence from 40 studies and suggests that astrocytic dysfunction, neuroinflammation, impaired waste clearance, and disrupted glutamate homeostasis may significantly contribute to the development and progression of CTE. The findings support a shift away from a neuron-centric view of CTE toward a broader neuroglial disease model.
Chronic traumatic encephalopathy is a progressive neurodegenerative disease associated with repetitive head impacts and traumatic brain injuries. It has been most commonly identified in contact-sport athletes, military personnel, and others exposed to repeated brain trauma. Traditionally, researchers have viewed CTE primarily as a neuron-centered disease characterized by the accumulation of abnormal tau proteins in the brain. However, this new review suggests that another type of brain cell—astrocytes—may play a much larger role in the disease process than previously recognized.
The review was led by Dr. Kameron Hahn and his team at Kansas City University School of Medicine. They examined 40 studies spanning postmortem human brain analyses, experimental models, molecular investigations, and biomarker research. "We studied the role of astrocytes in the pathogenesis of CTE, and to what extent astrocytic mechanisms contribute to disease initiation, propagation, and clinical manifestation relative to neuronal pathology," says Dr. Hahn.
Four major themes emerged across the literature: interface-specific astrogliosis; disruption of aquaporin-4-mediated waste-clearance pathways; astrocytic degeneration associated with impaired glutamate regulation; and chronic neuroinflammation driven by interactions between astrocytes and microglia. The authors observed that astrocytic abnormalities often appear early in the disease process—particularly around blood vessels or within cortical sulci subject to mechanical stress—which may indicate an active influence on subsequent neurodegeneration.
The review also highlights how disruption in aquaporin-4 water channels impairs metabolic waste clearance via the glymphatic system after repeated injury—a dysfunction potentially contributing to accumulation of hyperphosphorylated tau proteins characteristic of CTE pathology. Evidence further indicates that persistent inflammatory responses involving both astrocytes and microglia may accelerate tissue damage over time.
Clinical implications discussed include glial fibrillary acidic protein (GFAP) as a promising biomarker for monitoring neuroglial damage after injury—even though no definitive diagnostic marker for living individuals currently exists—and suggest that future approaches could incorporate such markers into multimodal diagnostics for earlier detection or prevention strategies. "The findings may ultimately help guide the development of earlier diagnostic tools and more effective interventions for individuals affected by repetitive head injuries," concludes Dr. Hahn.
