Ni2+与EGCG相互作用对人牙龈成纤维细胞的生物学效应

 目的 分析表没食子儿茶素没食子酸酯（epigallocatechin gallate，EGCG）、Ni²⁺及其相互作用对人牙龈成纤维细胞（human gingival fibroblast cells，HGF）的生物学效应。方法 用MTT法检测HGF的存活率，运用彗星电泳检测细胞的DNA损伤情况，使用流式细胞仪法检测HGF周期变化。结果 Ni²⁺可呈时间依赖性抑制HGF的生长，造成细胞DNA损伤，并且可使细胞周期阻滞于S期，诱导细胞凋亡。高浓度的EGCG（>200 μmol/L）可明显抑制HGF生长，使细胞的DNA损伤。Ni²⁺与EGCG相互作用后增加了对HGF的抑制（P<0.01），DNA的损伤及凋亡细胞也明显增加（P<0.05）。结论 Ni²⁺和EGCG相互作用后使Ni²⁺对HGF的抑制作用增强，加剧HGF的DNA损伤和细胞周期阻滞，并明显增加细胞凋亡。

The biological effect of interaction of Ni2+ and epigallocatechin gallate on human gingival fibroblast cells

Objective To determine the biological effects of epigallocatechin gallate (EGCG), Ni²⁺ and their interactions on human gingival fibroblast (HGF) cells. Methods The viability of cells was determined by the MTT reduction assay. To measure DNA damage, we followed a modified version of comet assay. Cell cycle was analyzed by flow cytometry. Results Ni²⁺ significantly inhibited the growth of HGF cells. Concentrations of Ni²⁺ greater than 100 μmol/L significantly increased DNA strand breaks damage and arrested the cell cycle. The high concentrations of EGCG (greater than 200 μmol/L) could inhibit the growth of HGF cells. Greater than 150 μmol/L EGCG could increase the DNA strand break damage. The co-treatment of Ni²⁺ and EGCG could increase Ni²⁺-induced inhibit effect on HGF cells (P<0.01), and the DNA damage was significantly increased (P<0.01). Conclusions Ni²⁺ mixed with EGCG could increase the Ni²⁺-induced damage on the HGF cells and the blockage of cell cycle.