Increased vascular leakage and endothelial cell (EC) dysfunction are major features of neurodegenerative diseases. Here, we investigated the mechanisms leading to EC dysregulation and asked whether altered mitochondrial dynamics in ECs impinge on vascular barrier integrity and neurodegeneration. We show that ocular hypertension, a major risk factor for developing glaucoma, induced mitochondrial fragmentation in retinal capillary ECs, accompanied by increased oxidative stress and ultrastructural ...