摘要
目的探讨同型半胱氨酸(Hcy)对克隆的胰岛β细胞NIT-1细胞株的存活率和凋亡的影响,以及对细胞内超氧化物歧化酶(SOD)的影响。方法将不同浓度的Hcy作用于NIT-1细胞后,用MTT的方法检测细胞生存率;用流式细胞仪Annexin V/PI双染色法和琼脂糖凝胶电泳检测不同浓度的Hcy作用不同时间对NIT-1细胞凋亡的影响;用黄嘌呤氧化酶法和WST结合的方法检测Hcy作用后的NIT-1细胞内SOD的活性。结果Hcy以时间、剂量依赖性的方式抑制NIT-1细胞的存活率(P<0.01)。Hcy可诱导NIT-1细胞的凋亡,随作用时间的延长和Hcy浓度增加NIT-1细胞的凋亡率逐渐增加,浓度为100μmol/L的Hcy作用24 h细胞凋亡明显增加,凋亡率为7.21%(P<0.01),250μmol/L的Hcy作用12 h后细胞凋亡率达8.91%(P<0.01)。100μmol/L的Hcy作用24 h后NIT-1细胞内SOD活性较正常组细胞下降20.2%(P<0.01)。结论Hcy可抑制NIT-1细胞的存活率,并以时间和剂量依赖性的方式诱导细胞凋亡;这些有害作用可能是通过抑制细胞内的SOD的活性而发挥作用,为研究保护胰岛细胞功能提供一种新的思路。
Objective To study the possible effect of homocysteine on apoptosis and superoxide dismutase （SOD） activity in cells of NIT-1 cell line, which is a mouse pancreatic beta-cell line derived from a transgenic NOD/Lt mouse. Methods NIT-1 cells were cultured in the culture medium containing 5.6mmol/L glucose. Homocysteine at various concentrations was added to the culture medium according to a time schedule. The cell viability was determined by MTT colorimetric assay. The apoptosis of NIT-1 cells was evaluated by flow cytometry Annexin V/PI double staining method and electrophoresis on agarose gel. The SOD activity in NIT-1 cells was also assayed. Results In comparison with that in the control group, the cell viability was inhibited by homocysteine in a time- and concentration-dependent manner. Both Annexin V/PI FACS and electrophoresis analysis on agarose gel indicated that cell apoptosis could be induced by homocysteine in a time- and concentration-dependent manner. In comparison with the control group, intra-cellular SOD activity significantly declined as the concentration of homocysteine increased to 100 μmol/L （P 〈 0.01）. Conclusion Homocysteine can inhibit the cell viability and induce cell apoptosis of NIT-1 cells in a time- and dose-dependent manner. These detrimental effects may be effectuated throngh inhibiting SOD activity in the cells. This provides a new thought for studying protection of pancreatic islet cell function.
出处
《中华老年多器官疾病杂志》
2008年第1期51-54,共4页
Chinese Journal of Multiple Organ Diseases in the Elderly
