Investigating the Role of PPARβ/δ in Retinal Vascular Remodeling Using Pparβ / δ -Deficient Mice.

Peroxisome proliferator-activated receptor (PPAR)beta/delta is a member of the nuclear receptor superfamily of transcription factors, which plays fundamental roles in cell proliferation and differentiation, inflammation, adipogenesis, and energy homeostasis. Previous studies demonstrated a reduced choroidal neovascularization (CNV) in Ppar beta/delta-deficient mice. However, PPAR beta/delta's role in physiological blood vessel formation and vessel remodeling in the retina has yet to be established. Our study showed that PPAR beta/delta is specifically required for disordered blood vessel formation in the retina. We further demonstrated an increased arteriovenous crossover and wider venous caliber in Ppar beta/delta-haplodeficient mice. In summary, these results indicated a critical role of PPAR beta/delta in pathological angiogenesis and blood vessel remodeling in the retina.