增龄对牙周细胞覆盖体外创面的影响

目的:以长期培养的牙周膜和牙龈成纤维细胞模拟老化细胞,在体外创面模型中,就增龄对牙周细胞覆盖创面的影响进行评价。方法:以反复传代12代以上的牙周膜、牙龈成纤维细胞作为老化(实验组)细胞,5代以内的牙周膜、牙龈成纤维细胞作为正常对照组。4种细胞接种于盖玻片直至融合。机械方法刮除部分融合细胞,形成宽约7mm的无细胞条带,即体外创面。创面形成后继续培养2、6、9d,固定玻片并作结晶紫染色。以计算机辅助图像分析系统对细胞覆盖体外创面的面积进行百分比定量,采用SAS6.12软件包进行样本均数的t检验。结果:实验组与对照组比较,实验组的牙周膜、牙龈成纤维细胞覆盖创面面积明显较少,创面形成第6、9d,其覆盖创面面积显著低于对照组,差异有显著性(P<0.05)。实验组与对照组牙周膜、牙龈成纤维细胞覆盖创面面积存在差异,对照组创面形成后第9d牙龈成纤维细胞覆盖创面面积显著高于牙周膜细胞,差异有显著性(P<0.05)。结论:老化牙周膜、牙龈成纤维细胞覆盖创面的能力弱于正常细胞。增龄可能损害牙周细胞对创面的覆盖能力。

Periodontal wound filling affected by aging in an in vitro model

PURPOSR: Using human periodontal ligament cells (PDLC) and gingival fibroblasts (GF) , that were cultured in vitro for a long period of time to simulate the aging cells, we evaluated the influence of aging on periodontal healing in an in vitro wound model. METHODS: Human PDLC and GF were cultured in vitro over to 12 passages as aging cells for experiment, the same type of cells that were cultured under 5 passages as younger for control. The in vitro wound models were mechanically created in subconfluent cultures of this 4 types of cells, by removing a 7mm wide band of the cell layer respectively. Wounded cultures were then incubated for 2, 6, 9 days in the same media. Slides were fixed, stained with crystal violet and cell filling area within the wound boundaries were quantified by computer-assisted histomorphometry. Statistical analysis was performed by SAS6.12 software package to determine the differences between the time points and groups. RESULTS: The ability of filling wound of aging PDLC and GF decreased,there was significant difference (P<0.05) at day 6, 9 between the experimental and control groups. There was difference between GF and PDLC in filling wound in vitro over 9 days of healing period in both groups, but only the experimental group showed significant difference (P<0.05) at 9th day after wound creating. CONCLUSION: The ability of filling wound of aging PDLC and GF were weaker then that of the younger. Within the limits of the present study, data analysis suggests that aging may impair the healing characterization of PDLC and GF. Supported by Research Fund of Shanghai Municipal Education Commission (Grant No.04BB25).