Exogenous Collagen Cross-linking Reduces Scleral Permeability: Modeling the Effects of Age-Related Cross-link Accumulation
Exogenous Collagen Cross-linking Reduces Scleral Permeability: Modeling the Effects of Age-Related Cross-link Accumulation
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DOI：
10.1167/iovs.08-2300
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发表时间：
2009-01-01
影响因子：
4.4
通讯作者：
Trinidad, Monique L.
中科院分区：
文献类型：
--
作者：
Stewart, Jay M.;Schultz, David S.;Trinidad, Monique L.
目的.探讨巩膜通透性与非酶交联密度之间的关系。从60只尸体猪眼的内侧和外侧赤道区解剖出直径18 mm的巩膜盘。将样品与对照溶液或浓度为0.001%、0.01%、0.10%和1.00%的甲基乙二醛孵育24小时。使用木瓜蛋白酶消化和荧光分光光度法定量测定处理组和对照组的非酶交联密度。将经处理的巩膜盘安装在连接到垂直管的定制的Ussing型室中，并且根据脱气盐水柱在室温下的下降来确定比水力传导率。对于另一组经处理的巩膜样本，测定静态室中荧光素扩散的渗透性。甲基乙二醛处理有效地增加了非酶交联含量，如各组的平均荧光所示。比导水率（m（2））随交联密度的增加而降低。同样地，荧光素溶质的渗透系数随着丙酮醛浓度的增加而一致地降低，表明来自处理的扩散阻抗。非酶交联密度可以显着增加与甲基乙二醛处理。随着交联密度的增加，猪巩膜的溶质渗透性和比导水率呈非线性降低。该模型表明，年龄相关的非酶交联积累可以对巩膜渗透性产生实质性影响。（Invest Ophthalmol维斯科学。2009; 50：352-357）DOI：10.1167/iovs.08-2300
PURPOSE. To investigate the relationship between scleral permeability and nonenzymatic cross-link density.METHODS. Scleral discs 18 mm in diameter were dissected from the medial and lateral equatorial regions of 60 cadaveric porcine eyes. Samples were incubated for 24 hours with control solution or methylglyoxal at concentrations of 0.001%, 0.01%, 0.10%, and 1.00%. Nonenzymatic cross-link density in treated and control groups was quantified with the use of papain digest and fluorescence spectrophotometry. Treated scleral discs were mounted in a customized Ussing-type chamber connected to vertical tubing, and specific hydraulic conductivity was determined according to the descent of a column of degassed saline at room temperature. Permeability to diffusion of fluorescein in a static chamber was determined for another set of treated scleral samples.RESULTS. Methylglyoxal treatment effectively increased nonenzymatic cross-link content, as indicated by the average fluorescence for each group. Specific hydraulic conductivity (m(2)) was reduced with increasing cross-link density. Similarly, the permeability coefficient for the fluorescein solute consistently decreased with increasing methylglyoxal concentration, indicating diffusion impedance from the treatment.CONCLUSIONS. Nonenzymatic cross-link density can be significantly increased by treatment with methylglyoxal. Porcine sclera showed a nonlinear reduction in solute permeability and specific hydraulic conductivity with increasing cross-link density. This model indicates that age-related nonenzymatic cross-link accumulation can have a substantial impact on scleral permeability. (Invest Ophthalmol Vis Sci. 2009; 50: 352-357) DOI: 10.1167/iovs.08-2300