Targeting Cx40 (Connexin40) Expression or Function Reduces Angiogenesis in the Developing Mouse Retina.

Jacques-Antoine Haefliger, Florent Allagnat, Lauriane Hamard, Loïc Le Gal, Paolo Meda, Denise Nardelli-Haefliger, Elisabeth Génot, Florian Alonso

Arteriosclerosis, thrombosis, and vascular biology 2017 Nov

filter terms:

Cx40 (Connexin40) forms intercellular channels that coordinate the electric conduction in the heart and the vasomotor tone in large vessels. The protein was shown to regulate tumoral angiogenesis; however, whether Cx40 also contributes to physiological angiogenesis is still unknown. Here, we show that Cx40 contributes to physiological angiogenesis. Genetic deletion of Cx40 leads to a reduction in vascular growth and capillary density in the neovascularization model of the mouse neonatal retina. At the angiogenic front, vessel sprouting is reduced, and the mural cells recruited along the sprouts display an altered phenotype. These alterations can be attributed to disturbed endothelial cell functions as selective reexpression of Cx40 in these cells restores normal angiogenesis. In vitro, targeting Cx40 in microvascular endothelial cells, by silencing its expression or by blocking gap junction channels, decreases their proliferation. Moreover, loss of Cx40 in these cells also increases their release of PDGF (platelet-derived growth factor) and promotes the chemoattraction of mural cells. In vivo, an intravitreal injection of a Cx40 inhibitory peptide, phenocopies the loss of Cx40 in the retinal vasculature of wild-type mice. Collectively, our data show that endothelial Cx40 contributes to the early stages of physiological angiogenesis in the developing retina, by regulating vessel growth and maturation. Cx40 thus represents a novel therapeutic target for treating pathological ocular angiogenesis. © 2017 American Heart Association, Inc.

Citation

Jacques-Antoine Haefliger, Florent Allagnat, Lauriane Hamard, Loïc Le Gal, Paolo Meda, Denise Nardelli-Haefliger, Elisabeth Génot, Florian Alonso. Targeting Cx40 (Connexin40) Expression or Function Reduces Angiogenesis in the Developing Mouse Retina. Arteriosclerosis, thrombosis, and vascular biology. 2017 Nov;37(11):2136-2146