RHI Causes Neuronal Loss in Young Athletes

Background: Chronic traumatic encephalopathy (CTE) has become an increasingly recognized consequence of contact sports, particularly American football. The characteristic finding is the postmortem finding of p-tau aggregates in neurons around blood vessels. The antecedent changes are not well understood. Objective: To identify the earlier changes that lead to the pathologic findings of CTE. Design: Postmortem brain tissue analysis. Methods: 28 brains were analyzed: 8 controls, 9 with repetitive head injury (RHI; 8 football players, 1 soccer player), and 11 with CTE. Tissue from the area typically involved in CTE was obtained and processed to obtain specific brain cell types such as astrocytes, endothelial cells, microglia, and neurons. Gene expression in each cell type was assessed for each group: controls, RHI, and CTE. Results: In microglia, there was an increase in inflammatory states and a change in microglial subpopulations in RHI- and CTE-exposed individuals but not in the cont more...