Emerging roles of transforming growth factor β signaling in wet age-related macular degeneration.

Age-related macular degeneration (AMD) is one of the major causes of irreversible blindness among aging populations in developed countries and can be classified as dry or wet according to its progression. Wet AMD, which is characterized by angiogenesis on the choroidal membrane, is uncommonly seen but more severe. Controlling or completely inhibiting the factors that contribute to the progression of events that lead to angiogenesis may be an effective strategy for treating wet AMD. Emerging evidence has shown that transforming growth factor- (TGF-) signaling plays a significant role in the progression of wet AMD. In this review, we described the roles of and changes in TGF- signaling in the development of AMD and discussed the mechanisms of the TGF- superfamily in choroidal neovascularization (CNV) and wet AMD, including the modulation of angiogenesis-related factors, inflammation, vascular fibrosis, and immune responses, as well as cross-talk with other signaling pathways. These remarkable findings indicate that TGF- signaling is a potential target for wet AMD treatment.