The dynamic expression of CD146 in corneal neovascularization and its significance

Abstract

Objective To investigate the expression and localization of CD146 in corneal neovascularization. Methods Fifty SPF male SD rats with the age of 8 weeks were randomly divided into 1 day group, 3 days group, 7 days group, 14 days group and normal control group by using random number table method, 10 rats for each group.Corneal neovascularization models were established by sticking the filter papers with NaOH on the central corneas.The area of corneal neovascularization was observed at different time points by slit lamp microscopy.The expression of CD146 mRNA and protein were detected by reverse transcription PCR and Western blot, respectively.The location of CD146 expression was observed by using immunohistochemical staining method.The animal feeding and use was in accordance with the standards set by the ARVO, and the experiment was approved by the Ethic Committee for Experimental Animal of Affiliated Hospital of Xuzhou Medical University (2016012). Results Corneal neovascularization occurred at 3 days and peaked at 7 days after alkali burn, then gradually subsided.The area of corneal neovascularization was (1.9±0.7), (10.3±1.1), (29.6±2.4) and (11.8±1.0)mm2 in 1 day, 3 days, 7 days and 14 days after alkali burn, respectively, the overall difference was statistically significant (F=650.976, P=0.000), and the area of corneal neovascularization in 1 day group, 3 days group, 14 days group was significantly shrinked compared with that in the 7 days group after alkali burn, with significant differences between them(t=-33.293, -20.475, 20.744, all at P=0.000), while there was no significant differences between the other groups (all at P>0.05). The relative expression levels of CD146 mRNA in the 1 day, 3 days, 7 days and 14 days group after alkali burn was 0.3±0.1, 1.1±0.2, 3.5±0.4 and 1.3±0.3, and the relative expression levels of CD146 protein was 0.2±0.1, 1.4±0.2, 4.1±0.5 and 1.3±0.2, respectively, the overall differences between the four groups were statistically significant (F=1 176.920, P=0.000; F=233.127, P=0.000), and the relative expression levels of CD146 mRNA and protein in the 1 day, 3 days, 7 days and 14 days group were lower than those in the 7 days group after alkali burn, with significant differences between them (mRNA: t=-58.109, -33.725, 31.006; all at P=0.000.protein: t=-59.873, -38.762, 39.153, all at P=0.000). Immunohistochemical results showed that CD146 was highly expressed in corneal neovascular endothelial cells at 7 days after alkali burn, forming lumen structure, while only weak expression of CD146 could be detected in mature corneal neovascularization at 14 days after modeling. Conclusions CD146 is closely related to corneal neovascularization formation, and it is promising as a new target for treatment. Key words: Corneal neovascularization; CD146; Animal model