TGFB1 and Alzheimer disease: The serum VEGF concentration in AD patients is significantly lower than in patients with (aMCI) and healthy controls. The VEGF level in aMCI patients is also significantly lower than in healthy controls. Additionally, TGF-β1 levels are significantly reduced in both AD and aMCI patients compared to controls. Serum VEGF/TGF-β1 levels are negatively correlated with Clinical Dementia Rating (CDR), while serum VEGF levels are positively correlated with TGF-β1 levels.