Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, Ube City, Yamaguchi, Japan.
Invest Ophthalmol Vis Sci. 2012 Jun 28;53(7):4213-9. doi: 10.1167/iovs.11-8822.
To examine the effect of medroxyprogesterone 17-acetate (MPA) on interleukin-1β (IL-1β)-induced collagen degradation by corneal fibroblasts.
Rabbit corneal fibroblasts were cultured in three-dimensional collagen gels with or without MPA. Collagen degradation was determined by measurement of hydroxyproline after acid hydrolysis. The expression or activity of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) was evaluated by immunoblot analysis or gelatin zymography. The phosphorylation of mitogen-activated protein kinases (MAPKs) in corneal fibroblasts was examined by immunoblot analysis. Cell proliferation and viability were evaluated by measurement of bromodeoxyuridine incorporation and the release of lactate dehydrogenase, respectively.
MPA inhibited IL-1β-induced collagen degradation by corneal fibroblasts in a concentration- and time-dependent manner. MMP expression and activation as well as TIMP expression in corneal fibroblasts exposed to IL-1β were also inhibited by MPA. MPA had no effect on cell proliferation or viability. MPA inhibited the IL-1β-induced phosphorylation of p38 MAPK without affecting that of the MAPKs ERK or JNK. IL-1β-induced MMP expression and activation as well as collagen degradation were also blocked by the p38 MAPK inhibitor SB203580.
MPA inhibited MMP expression and thereby suppressed collagen degradation by corneal fibroblasts induced by IL-1β. Furthermore, inhibition of p38 MAPK phosphorylation by MPA may contribute to its inhibition of collagen degradation.
研究醋酸甲羟孕酮（MPA）对白细胞介素-1β（IL-1β）诱导的角膜成纤维细胞胶原降解的影响。
将兔角膜成纤维细胞在含或不含 MPA 的三维胶原凝胶中培养。通过酸水解后羟脯氨酸的测定来确定胶原降解。通过免疫印迹分析或明胶酶谱法评估基质金属蛋白酶（MMPs）和金属蛋白酶组织抑制剂（TIMPs）的表达或活性。通过免疫印迹分析检查角膜成纤维细胞中丝裂原活化蛋白激酶（MAPKs）的磷酸化。通过溴脱氧尿苷掺入和乳酸脱氢酶释放分别测量细胞增殖和活力。
MPA 以浓度和时间依赖的方式抑制 IL-1β诱导的角膜成纤维细胞胶原降解。暴露于 IL-1β的角膜成纤维细胞中 MMP 的表达和激活以及 TIMP 的表达也被 MPA 抑制。MPA 对细胞增殖或活力没有影响。MPA 抑制了 IL-1β诱导的 p38 MAPK 磷酸化，而不影响 ERK 或 JNK 等 MAPKs 的磷酸化。p38 MAPK 抑制剂 SB203580 也阻断了 IL-1β诱导的 MMP 表达和激活以及胶原降解。
MPA 抑制 MMP 的表达，从而抑制 IL-1β诱导的角膜成纤维细胞胶原降解。此外，MPA 抑制 p38 MAPK 磷酸化可能有助于其抑制胶原降解。
