中药单体成分大黄素对胰岛β细胞NIT-1的影响

Effects of Emodin on insulinoma cell line NIT-1

目的研究中药提取的单体成分大黄素对胰岛β细胞NIT-1增殖、凋亡及胰岛素分泌作用的影响。方法不同浓度的大黄素分别作用于NIT-1细胞不同时间。以MTT法检测细胞的增殖活性;收集细胞,以Annexin V/PI染色,经流式细胞术检测细胞凋亡发生率;收集细胞培养上清液测定基础和高糖刺激后胰岛素分泌量。结果2.5μg/mL大黄素作用于NIT-1细胞时对其增殖无明显影响,5.0μg/mL以上对NIT-1细胞增殖的影响呈时间和剂量依赖性降低(P<0.01);0～25.0μg/mL大黄素分别作用于NIT-1细胞24h后,细胞凋亡率呈浓度依赖性增加(P<0.05);0～5.0μg/mL大黄素分别作用于NIT-1细胞24h后,基础胰岛素分泌量呈浓度依赖性降低(P<0.05);高糖刺激后胰岛素分泌量在大黄素0和2.5μg/mL组间无差别,而在5.0μg/mL组则明显降低(P<0.05)。结论大黄素可诱导胰岛细胞凋亡,并抑制胰岛素分泌。

[Objective] To study the effects of Emodin on proliferation and apoptosis and insulin secretion of insulinoma cell line NIT-1. [Methods] NIT-1 cells were cultured with Emodin（0-25.0μg/mL respectively）. NIT- 1cells were incubated for 24-96 h, and then the vability were determined by MTT. Emodin-induced apoptosis was /dent/fled by flow cytometry stained with Annexin V/PI. Insulin concentrations in culture medium were determined by radio immunoassay. [Results] The proliferation of NIT-1 cell was inhibited significantly by Emodin in time- and dose-dependent manner （P 〈0.01）. The ratio of apoptosis of emodin treated NIT-1 cell was significantly higher than the control group （P 〈0.05）. The basic insulin secretion was inhibited by Emodin at the concentration of 2.5 and 5.0 μg/mL, the high glucose-stimulated insulin secretion was inhibited at 5.0 μg/mL （P 〈0：05）. [Conclusion] The results suggested that Emodin might induce NIT-1 cell apoptosis, and inhibit insulin secretion.