Fig. 1

CHI3L1 and its Role in the Pathogenesis of Acute and Chronic Brain Disorders. CHI3L1 contributes to neuronal death, degeneration, increased blood–brain barrier (BBB) permeability, neuroinflammation, and angiogenesis. Activated microglia and reactive astrocytes play a central role in these brain conditions. The activation of these glial cells leads to the release of inflammatory cytokines, such as IL-6, TNF-α, IL-1β, and IFN-γ, causing neuronal damage and driving the progression of brain diseases