Falconi M, Teti G, Zago M, Pelotti S, Breschi L, Mazzotti G
Dipartimento di Scienze Anatomiche Umane e Fisiopatologia dell'Apparato Locomotore, Università di Bologna, Italy.
Cell Biol Toxicol. 2007 Sep;23(5):313-22. doi: 10.1007/s10565-006-0148-3. Epub 2007 May 4.
The cytotoxicity of dental composites has been attributed to the release of residual monomers from polymerized adhesive systems due to degradation processes or the incomplete polymerization of materials. 2-Hydroxyethyl methacrylate (HEMA) is one of the major components released from dental adhesives. Cytotoxic effects due to high concentrations of HEMA have already been investigated, but the influence of minor toxic concentrations on specific proteins such as type I collagen has not been studied in depth. The objective of this project was to study the effect of minor toxic concentrations of HEMA on human gingival fibroblasts (HGFs), investigating modification in cell morphology, cell viability, and the influence on type I collagen protein. Primary lines of human gingival fibroblasts were exposed to 3 mmol/L HEMA for different periods of time (24 h, 72 h, 96 h). The cell vitality was determined by MTT assay, and high-resolution scanning electron microscopy analysis was performed to evaluate differences in cell morphology before and after treatment. The presence and localization of type I collagen was determined by immunofluorescence in HGFs treated with HEMA for the same period of time. The vitality of the cells decreased after 72 h of exposure. The HGFs grown in monolayer and observed by field emission in-lens scanning electron microscopy demonstrated a preserved surface morphology after 24 h of treatment, while they showed an altered morphology after 96 h of treatment. Immunofluorescence demonstrated a reduction of type I collagen due to HEMA exposure after 96 h. From these results, we conclude that low concentrations of HEMA can significantly alter the morphology of human gingival fibroblasts and interfere with the presence of type I collagen protein.
牙科复合材料的细胞毒性归因于聚合粘合剂系统因降解过程或材料不完全聚合而释放的残留单体。甲基丙烯酸2-羟乙酯（HEMA）是牙科粘合剂释放的主要成分之一。高浓度HEMA的细胞毒性作用已得到研究，但微量毒性浓度对特定蛋白质（如I型胶原蛋白）的影响尚未深入研究。本项目的目的是研究微量毒性浓度的HEMA对人牙龈成纤维细胞（HGFs）的影响，研究细胞形态、细胞活力的变化以及对I型胶原蛋白的影响。将人牙龈成纤维细胞原代细胞暴露于3 mmol/L HEMA不同时间（24小时、72小时、96小时）。通过MTT法测定细胞活力，并进行高分辨率扫描电子显微镜分析以评估处理前后细胞形态的差异。通过免疫荧光法测定相同时间段用HEMA处理的HGFs中I型胶原蛋白的存在和定位。暴露72小时后细胞活力下降。在单层生长并通过场发射内透镜扫描电子显微镜观察的HGFs在处理24小时后表面形态保持不变，而在处理96小时后形态发生改变。免疫荧光显示96小时后由于HEMA暴露I型胶原蛋白减少。从这些结果，我们得出结论，低浓度的HEMA可显著改变人牙龈成纤维细胞的形态并干扰I型胶原蛋白的存在。
