Decreased expression of gap junction delta-2 (GJD2) messenger RNA and connexin 36 protein in form-deprivation myopia of guinea pigs

作     者：Guo-Yuan Yang Feng-Yang Liu Xia Li Qiu-Rong Zhu Bing-Jie Chen Long-Qian Liu Yang Guo-Yuan;Liu Feng-Yang;Li Xia;Zhu Qiu-Rong;Chen Bing-Jie;Liu Long-Qian

作者机构：Department of OpthalmologyWest China HospitalSichuan UniversityChengduSichuan 610041China Department of OphthalmologyFirst Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China 

出 版 物：《Chinese Medical Journal》 (中华医学杂志（英文版）)

年 卷 期：2019年第132卷第14期

页      面：1700-1705页

核心收录：

学科分类：1002[医学-临床医学] 10[医学] 

基　　金：supported by a grant from Department of Science and Technology of Sichuan Province Fund for Medical Sciences 

主　　题：Connexin 36 Myopia Guinea pigs Gap junction 

摘      要：Background:More than ten genome-wide association studies have identified the significant association between the gap junction delta-2 (GJD2) gene and myopia.However,no functional studies have been performed to confirm that this gene is correlated with myopia.This study aimed to observe how this gene changed in mRNA and protein level in the form-deprivation myopia (FDM) animal model.Methods:Four-week-old guinea pigs were randomly divided into two groups:control and FDM groups (n =12 for each group).The right eyes of the FDM group were covered with opaque hemispherical plastic lenses for 3 weeks.For all the animals,refractive status,axial length (AL),and corneal radius of curvature were measured at baseline and 3 weeks later by streak retinoscope,A-scan ultrasonography,and keratometer,respectively.Retinal GJD2 mRNA expression and connexin 36 (Cx36) levels in FDM and control groups were measured by quantitative real-time PCR and Western blot analyses,respectively.Those results were compared using independent t test,Mann-Whitney U test,or paired t test.A significance level of P 0.05 was used.Results:Three weeks later,the FDM group (form-deprived eyes) showed about a myopic shift of approximately-6.75 (-7.94 to -6.31) D,while the control group remained hyperopic with only a shift of-0.50 (-0.75 to 0.25) D (Z =-3.38,P 0.01).The AL increased by 0.74 (0.61-0.76) and 0.10 (0.05-0.21) mm in FDM and control groups,respectively (Z =-3.37,P 0.01).The relative mRNA expression of GJD2 in the FDM group decreased 31.58% more than the control group (t =11.44,P 0.01).The relative protein expression of CX36 on the retina was lowered by 37.72% in form-deprivation eyes as compared to the controls (t=17.74,P 0.01).Conclusion:Both the mRNA expression of GJD2 and Cx36 protein amount were significantly decreased in the retina of FDM guinea pigs.This indicates that Cx36 is involved in FDM development,providing compensating evidence for the results obtained from genome-wide association studies.