Abstract
Abstract: :
Purpose: The Krüppel–like factors (KLFs) nuclear transcription factors family regulate numerous cell processes in various human tissues as digestive tract, placenta and lung. Accumulating publications supports an important role for these factors in vascular biology. Neovascularization remains a severely disabling condition, resulting in loss of the immunologic privilege of the cornea and in visual impairment. Given the fact that we recently demonstrated that the KLFs were expressed in human ocular surface, we sought to explore KLFs implication in corneal angiogenesis. The first step was to evaluate the mRNA levels of key genes in angiogenesis in a sutured–induced mouse corneal model of neovascularization. Then we determine mRNA levels of KLFs (fifteen members) in angiogenesis versus normal mouse cornea. Materials and Methods: Eight mice used for suture–induced CNV experiments (Right eye versus Left eye control) were between 8 and 12 weeks of age and were treated in accordance with the ARVO Statement for the Use of Animals in Ophthalmic and Vision Research. In order to evaluate the mRNA levels of key genes in angiogenesis and KLFs, total RNA was isolated from cornea (eight days after suture–induced CNV). Relative quantitative RT–PCR was performed with key genes in angiogenesis–specific primers (VEGFA, VEGFR2, FGF2, FGF2R, TGFb1, TGFbR, endoglin, Angiopoietin, Tie2, PDGF, PDGFR, Thrombospondin, TNFAIP2, Akt3, uPA, MMP19, PAI–1, PECAM), KLFs–specific primers and primer sets for GAPDH RNA used as an internal standard. In order to check the localization of PECAM proteins, immunohistochemistry experiments were realized on normal and angiogenesis cornea. Results: The mRNA levels of key genes demonstrate their classical variation in this late stage of angiogenesis. The immunohistochemistry confirm the corneal neovasularization process. We find significant increase of KLF2, KLF7, KLF9, KLF10 and significant decrease of KLF4, KLF5, and KLF14. Conclusions: In conclusion, the present study demonstrates for the first time, the potential implications of some KLFs in corneal neovascularization, using an established mouse corneal angiogenesis model.
Keywords: cornea: basic science • transcription factors