血管内皮生长因子-A165对形觉剥夺性近视豚鼠巩膜重塑的影响

Effect of vascular endothelial growth factor-A165 on scleral remodeling of guinea pigs with form-deprivation myopia

摘要:

目的：探讨玻璃体腔内注射血管内皮生长因子-A165(VEGF-A165)对形觉剥夺性近视(FDM)豚鼠巩膜重塑的影响。方法：健康3周龄三色豚鼠120只随机分为6组，每组20只，其中空白组不做任何干预，FDM组仅建立FDM模型，PBS组建立FDM模型前玻璃体腔内注射PBS缓冲液2.5μL，1ng组、5ng组、10ng组建立FDM模型前玻璃体腔内分别注射VEGF-A165 1、5、10ng。用半透明气球遮盖豚鼠右眼14d建立FDM模型，造模前后测量豚鼠右眼屈光度和眼轴长度，造模14d后采用高效液相色谱法检测视网膜中多巴胺(DA)含量，用RT-PCR、Western blot法检测巩膜中基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶抑制剂-2(TIMP-2)、转化生长因子(TGF)-β1、TGF-β2、α-平滑肌肌动蛋白(α-SMA)的mRNA和蛋白表达情况。结果：造模前，各组豚鼠右眼屈光度和眼轴长度均无显著差异(P>0.05)。造模14d后，与空白组相比，FDM组豚鼠右眼近视度数升高，眼轴增长，视网膜中DA含量减少，巩膜中MMP-2、TGF-β2、α-SMA表达量均增加，TIMP-2、TGF-β1表达量均减少(P<0.01)； 与FDM组相比，1ng组、5ng组、10ng组豚鼠右眼近视度数均降低，眼轴增长趋势均减缓，视网膜中DA含量均增加，巩膜中MMP-2、TGF-β2、α-SMA表达量均减少，TIMP-2、TGF-β1表达量均增加(P<0.01)，且随着玻璃体腔注射VEGF-A165浓度的升高，豚鼠右眼近视度数逐渐升高，眼轴逐渐延长，视网膜中DA含量逐渐减少，巩膜中MMP-2、TGF-β2、α-SMA表达量均逐渐增加，TIMP-2、TGF-β1表达量均逐渐减少。结论：玻璃体腔内注射VEGF-A165可以增加FDM豚鼠视网膜中DA含量，影响巩膜中MMP-2、TIMP-2、TGF-β1、TGF-β2、α-SMA的表达，抑制巩膜重塑，其中1ng VEGF-A165效果最明显。

Abstract:

AIM: To investigate the effect of the intravitreal injection of vascular endothelial growth factor-A165(VEGF-A165)on the scleral remodeling of guinea pigs with form-deprivation myopia(FDM).METHODS: A total of 120 tricolor guinea pigs, aged three weeks, were randomly divided into 6 groups, with 20 in each group. The blank group did not undergo any intervention. In the FDM group, only the FDM model was established. In the phosphate buffer saline(PBS)group, 2.5 μL of PBS was injected into the vitreous cavity before establishing the FDM model. In the 1ng group, 5ng group, and 10ng group, VEGF-A165 was injected into the vitreous cavity at concentrations of 1, 5 and 10ng, respectively, before the establishment of the FDM model. The FDM model was established by covering the right eyes of guinea pigs with translucent balloons for 14d. The diopter and axial length of the right eyes were measured before and after covering. After 14d, the content of dopamine(DA)in retina was measured by high performance liquid chromatography. Additionally, the mRNA and protein expression levels of matrix metalloproteinase-2(MMP-2), tissue inhibitor of matrix metalloproteinase-2(TIMP-2), transforming growth factor(TGF)-β1, TGF-β2 and α-smooth muscle actin(α-SMA)in sclera were detected by reverse transcription polymerase chain reaction(RT-PCR)and Western blot.RESULTS: Before covering, there were no significant differences in the diopter and axial length of the right eyes of guinea pigs in all groups(P>0.05). After 14d of modeling, when compared with the blank group, FDM group showed an increase in the degree of myopia in the right eye, a prolongation of the axial length, a decrease in the content of DA in the retina, and an increase in the expression of MMP-2, TGF-β2 and α-SMA in the sclera. Conversely, the expression of TIMP-2 and TGF-β1 were decreased(P<0.01). However, in comparison to the FDM group, the degree of myopia in the 1ng, 5ng, and 10ng groups of guinea pigs decreased, the growth trend of axial length slowed, the content of DA in the retina increased, and the expression of MMP-2, TGF-β2 and α-SMA in the sclera decreased. Furthermore, the expression of TIMP-2 and TGF-β1 in the sclera increased(P<0.01). As the concentration of intravitreal injection of VEGF-A165 increased, the degree of myopia in the right eye of guinea pigs gradually increased, and the axial length gradually prolonged. The content of DA in the retina gradually decreased, the expression of MMP-2, TGF-β2, and α-SMA in the sclera gradually increased, while the expression of TIMP-2 and TGF-β1 decreased gradually.CONCLUSION: Intravitreal injection of VEGF-A165 can increase the content of DA in the retina of FDM guinea pigs, affect the expression of MMP-2, TIMP-2, TGF-β1, TGF-β2 and α-SMA in the sclera, and inhibit scleral remodeling of guinea pigs. Notably, the VEGF-A165 at the concentration of 1ng showed the most significant efficacy.