Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany.
Invest Ophthalmol Vis Sci. 2010 May;51(5):2721-9. doi: 10.1167/iovs.09-4661. Epub 2009 Dec 17.
To reveal the effects of minocycline, an anti-inflammatory and neuroprotective agent, on the viability and physiological properties of retinal pigment epithelial (RPE) cells and to compare the effects with those of triamcinolone acetonide.
The proliferation of human RPE cells in vitro was investigated with a bromodeoxyuridine immunoassay; chemotaxis was examined with a Boyden chamber assay. Cell viability was determined by trypan blue exclusion. The gene expression of growth factors and MMP-9 was determined with real-time RT-PCR, and the secretion of VEGF was examined with ELISA. The phosphorylation of p38 MAPK and ERK1/2 proteins was determined with Western blot analysis.
Minocycline at low concentrations (50 nM-20 microM) stimulated chemotaxis and decreased the proliferation of RPE cells. Minocycline at high concentrations (above 5 microM) decreased the viability of RPE cells through the induction of cell necrosis. The chemotactic effect of minocycline was mediated by the stimulation of autocrine PDGF signaling and the activation of p38 MAPK. Minocycline promoted the expression of PDGF-B, HGF, VEGF, and MMP-9 and increased the amounts of phosphorylated p38 and ERK1/2 proteins in RPE cells. Triamcinolone reduced PDGF-evoked chemotaxis and VEGF expression and secretion and had no significant effects on cell viability and proliferation. Triamcinolone did not reverse the effects of minocycline on cell proliferation, chemotaxis, or viability or the expression of VEGF.
Low-dose minocycline induces the activation of RPE cells, as indicated by the activation of p38 and ERK1/2 and by enhanced chemotaxis mediated by autocrine PDGF signaling. High-dose minocycline induces RPE cell degeneration.
揭示米诺环素（一种抗炎和神经保护剂）对视网膜色素上皮（RPE）细胞活力和生理特性的影响，并将其与曲安奈德的作用进行比较。
通过溴脱氧尿苷免疫测定法检测体外人 RPE 细胞的增殖；用 Boyden 室测定法检测趋化性。通过台盼蓝排除法测定细胞活力。用实时 RT-PCR 测定生长因子和 MMP-9 的基因表达，用 ELISA 测定 VEGF 的分泌。用 Western blot 分析测定 p38 MAPK 和 ERK1/2 蛋白的磷酸化。
米诺环素在低浓度（50 nM-20 microM）下刺激趋化作用并降低 RPE 细胞的增殖。米诺环素在高浓度（5 microM 以上）下通过诱导细胞坏死降低 RPE 细胞的活力。米诺环素的趋化作用是通过刺激自分泌 PDGF 信号和激活 p38 MAPK 介导的。米诺环素促进 PDGF-B、HGF、VEGF 和 MMP-9 的表达，并增加 RPE 细胞中磷酸化的 p38 和 ERK1/2 蛋白的量。曲安奈德降低 PDGF 诱导的趋化作用和 VEGF 表达和分泌，对细胞活力和增殖没有显著影响。曲安奈德不能逆转米诺环素对细胞增殖、趋化作用或活力或 VEGF 表达的影响。
低剂量米诺环素诱导 RPE 细胞激活，表现为 p38 和 ERK1/2 的激活以及自分泌 PDGF 信号介导的趋化作用增强。高剂量米诺环素诱导 RPE 细胞退化。
