BDNF and glaucoma: Prolonged anxiety elevates glucocorticoid levels, affecting glaucoma progression through dual mechanisms: cortisol directly inhibits trabecular meshwork cell phagocytosis by activating glucocorticoid receptors, leading to abnormal protein deposition in the aqueous outflow pathway (29); HPA axis dysfunction downregulates retinal neurotrophic factors such as brain-derived neurotrophic factor (BDNF), as validated in the chronic unpredictable mild stress (CUMS) animal model, where RGC survival rate decreases by 43% (30).