The Role of Collagen-Binding Integrin β1 in Scleral Remodelling during Induced Myopia and Recovery
Abstract: Objective: To investigate the role of collagen-binding integrin β1 in sclera remodeling process of the guinea pig form-deprivation myopia (FDM). Methods: 128 young guinea pigs, aged 2 to 3 weeks, were randomized into experimental group (n = 64) and normal control group (n = 64). FDM models were monocular deprived by placement of a facemask over the right eye in the experimental group, and the fellow eyes served as the contralateral control eyes. The guinea pigs in the normal control group were raised with both eyes untreated. The FDM eyes were monocular deprived for 1, 2 and 4 weeks, and recovered 1, 3, 5, 7, 14 days after occluding for 4 weeks. Optical measurements and axial length were accomplished at all of the time points. The histological analysis was applied to assess the posterior sclera changes, and immunohistochemical staining and quantitative real-time PCR (QRT-PCR) were applied to investigate the expression of integrin β1 protein and mRNA. Results: After 2 and 4 weeks, compared with the fellow eyes and the normal control group, the refraction diopter of the experimental group was (−3.00 ± 0.50) D and (−5.50 ± 1.08) D, and the axial length elongated (0.22 ± 0.06) mm and (0.49 ± 0.11) mm, showing significant differences respectively (P < 0.05); but in 1 week, the statistics showed no difference among those groups (P > 0.05). After re-exposure, the right eyes of guinea pigs in the experimental group experienced re-normalization and the refraction was rapidly recovered in the initial 7 days (P > 0.05); the axial length gradually shortened, and it was statistically non-significant after 14-day recovery (P > 0.05). The morphological observation of sclera found that the posterior sclera collagen fiber arrangement of guinea pigs with FDM was disordered and the sclera became thinner. Scleral integrin β1 mRNA and protein expression in FDM eyes were significantly lower than those in the controls after monocular deprived 1 week (P < 0.05). One day after occlusion had been removed, the expression of integrin β1 was up-regulated but lower than that in the controls (P < 0.05), and the difference was non-significant after 7-day recovery (P > 0.05). The difference of all the above statistics between contralateral control eyes and the normal control group was not remarkable (P > 0.05). Conclusion: Form-deprivation myopia was able to be induced by monocular covering. Guinea pigs aged 2 to 3 weeks with form-deprivation can experience re-normalization after recovery, along with the shortening of the axial length. The main recovery stage of ocular biometric parameters was in the initial 7 days. The expression of integrin β1 in FDM sclera was found to be lower, but could be restored during the recovery period. This suggests that collagen- binding integrin β1 may be involved in the pathogenesis of myopia, and further study needs to be done on the mechanism of the scleral remodeling in myopia.
文章引用: 王 园 , 杨 先 , 刘 静 , 王 青 , 刘桂波 (2015) 胶原相关整合素β1在形觉剥夺性近视诱导及恢复期中调节巩膜重塑作用的研究。 眼科学， 4， 1-9. doi: 10.12677/HJO.2015.41001
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