Increased VEGF-A promotes multiple distinct aging diseases of the eye through shared pathomechanisms

While increased VEGF-A has been associated with neovascular age-related macular degeneration (AMD), it is not known whether VEGF-A may also promote other age-related eye diseases. Here, we show that an increase in VEGF-A is sufficient to cause multiple distinct common aging diseases of the eye, including cataracts and both neovascular and non-exudative AMD-like pathologies. In the lens, increased VEGF-A induces age-related opacifications that are associated with ERK hyperactivation, increased oxidative damage, and higher expression of the NLRP3 inflammasome effector cytokine IL-1β. Similarly, increased VEGF-A induces oxidative stress and IL-1β expression also in the retinal pigment epithelium (RPE). Targeting NLRP3 inflammasome components or Il1r1 strongly inhibited not only VEGF-A-induced cataract formation, but also both neovascular and non-exudative AMD-like pathologies. Moreover, increased VEGF-A expression specifically in the RPE was sufficient to cause choroidal neovascularization (CNV) as in neovascular AMD, which could be inhibited by RPE-specific inactivation of Flk1, while Tlr2 inactivation strongly reduced CNV. These findings suggest a shared pathogenic role of VEGF-A-induced and NLRP3 inflammasome-mediated IL-1β activation for multiple distinct ocular aging diseases.