甲状腺激素T_3诱导K562细胞铁蛋白表达与细胞凋亡和生长的关系

Ferritin expression of K562 cell induced by thyroid hormone T_3 and apoptosis and proliferation cycle of the cells

目的 探讨甲状腺激素T3对K562细胞铁蛋白表达及其对细胞凋亡和增殖的影响。方法 收集各组细胞胞浆蛋白,用放射免疫法检测铁蛋白含量,并用流式细胞术分析各组细胞凋亡百分率及细胞周期变化。结果 中等浓度及高浓度的T3均能增加K562细胞铁蛋白表达,与空白对照相比有显著性差异（P<0.05）,且随T3浓度增加,铁蛋白的表达亦增高。同一浓度T3与K562细胞共培养,随时间延长,铁蛋白表达增加,与空白对照相比具有显著性差异（P<0.01）。24h培养组细胞凋亡率较空白对照略有下降,差异有统计学意义,72h培养组T3=200nM时凋亡百分率明显下降。T3各处理组中S+G2期细胞比例较空白对照组明显减少（P<001）,且72h各组G2+S细胞百分率较24h明显下降。结论 甲状腺激素T3能诱导K562细胞铁蛋白表达增加,且能干预细胞凋亡和细胞增殖周期。

Objectives To explore the effect of thyroid hormone T3 on ferritin expression of K562 cell and on the apoptosis and proliferation cycle of the cells. Methods Plasmic protein in groups of cells was collected and radioimmunoassay (RIA) was used for plasmic ferritin measurement. Flow cytometry was used to analyze the percentage of cell apoptosis and the modulation of cell cycle. Results T3 at moderate and high concentrations (T3 = 100 nM and 200 nM) could induce ferritin expression of K562 cell to increase markedly (92.25±3.55 ng/μl and 90.55±1.33 ng/μl). Incubation of cells with T3 = 100 nM the ferritin expression was time deper-dent: 35.6±4.8 ng/μl for 24 h, 49.4± 2.2 ng/μl for 48 h and 91.4± 3.3 ng/μl for 72 h, and all the values were significantly higher than control group(P <0. 01). Incubation of the cells with T3 at different concentration made the apoptosis rate decrease markedly, while for 72 h groups only when T3 = 200 nM the apoptosis (9.53 % +0.34 % ) was caused to decrease significantly compared with the control group. The cell rate of S + G2 stage decreased when incubated with T3 at different concentrations. Conclusions Thyroid hormone T3 can enhance ferritin expression of K562 cells and it may also influence cell apoptosis and cell proliferation cycle.