Faculty of Kinesiology, Human Performance Laboratory, University of Calgary, Calgary, Canada.
Eye Contact Lens. 2012 Jan;38(1):27-35. doi: 10.1097/ICL.0b013e31823f7041.
Proteoglycan 4 (PRG4), also known as lubricin, is a boundary lubricating mucin-like glycoprotein present on several tissue surfaces in the body. The objectives of this study were to (1) implement and characterize an in vitro boundary lubrication test at a human cornea-polydimethylsiloxane (PDMS) biointerface and (2) determine the dose-dependent and synergistic effects of PRG4, with hyaluronan (HA), on ocular surface boundary lubrication using this test.
Human corneas and model PDMS material were articulated against each other, at effective sliding velocities v(eff) between 0.3 and 30 mm/sec under physiologic loads of approximately 8 to 25 kPa. Samples were tested serially in (1) saline, PRG4 at 30, 100, 300 μg/mL resuspended in saline, then saline again or (2) saline, AQuify Comfort Eye Drops (containing 0.1% HA), 300 μg/mL PRG4 in saline, 300 μg/mL PRG4 in AQuify, then saline again. Both static and kinetic friction coefficients were calculated.
PRG4 effectively lowered friction at the cornea-PDMS biointerface, both alone in a dose-dependent manner and in combination with HA. PRG4 reduced kinetic friction coefficients, <μ(kinetic, Neq)>, from approximately 0.30 in saline, to approximately 0.30, 0.24, and 0.17 in 30, 100, and 300 μg/mL PRG4, respectively. Values of <μ(kinetic, Neq)> in AQuify, approximately 0.32, were similar to those in saline; however, when combined with 300 μg/mL PRG4, values of <μ(kinetic, Neq)> were reduced to approximately 0.15.
PRG4 functions as an effective ocular surface boundary lubricant, both alone in a dose-dependent manner and in combination with HA.
蛋白聚糖 4（PRG4），也称为黏蛋白-4，是一种存在于体内几种组织表面的边界润滑黏蛋白样糖蛋白。本研究的目的是：（1）在人眼角膜-聚二甲基硅氧烷（PDMS）生物界面实施并表征一种体外边界润滑试验；（2）使用该试验确定 PRG4 与透明质酸（HA）剂量依赖性和协同作用对眼表面边界润滑的影响。
在大约 8 至 25kPa 的生理负荷下，将人眼角膜和模型 PDMS 材料以 0.3 至 30mm/sec 的有效滑动速度 v(eff)相互对接。样品依次在（1）生理盐水、30、100、300μg/mL 的 PRG4 悬浮于生理盐水中，然后再用生理盐水；或（2）生理盐水、AQuify Comfort Eye Drops（含 0.1%HA）、300μg/mL 的 PRG4 生理盐水、300μg/mL 的 PRG4 在 AQuify 中，然后再用生理盐水进行测试。计算了静态和动态摩擦系数。
PRG4 以剂量依赖的方式单独作用或与 HA 联合作用，都能有效降低角膜-PDMS 生物界面的摩擦力。PRG4 降低了动力学摩擦系数<μ(kinetic, Neq)>，从生理盐水的约 0.30 降低至 30μg/mL、100μg/mL 和 300μg/mL 的 PRG4 分别为约 0.30、0.24 和 0.17。AQuify 中的<μ(kinetic, Neq)>值约为 0.32，与生理盐水相似；然而，当与 300μg/mL 的 PRG4 结合使用时，<μ(kinetic, Neq)>值降低至约 0.15。
PRG4 作为一种有效的眼表面边界润滑剂，无论是单独使用还是与 HA 联合使用，都具有剂量依赖性。
