脂多糖对甲状腺上皮细胞增殖、吞噬及胞内活性氧产生的影响

目的: 研究脂多糖（lipopolysaccharides，LPS）对甲状腺上皮细胞（thyroid follicular cells，TFCs）的增殖、凋亡、吞噬和胞内活性氧产生的影响，探讨脂多糖对TFCs的病理损伤作用。方法: 用0、10、20、100、150 ng·mL-1的脂多糖作用TFCs系Nthy-ori 3-1细胞48 h及100 ng·mL-1的脂多糖作用Nthy-ori 3-1细胞24 h和48 h，MTT法检测各组细胞的增殖；流式细胞术检测100 ng·mL-1脂多糖作用Nthy-ori 3-1细胞48 h时的凋亡率。荧光微球摄入法检测0、10、20、100 ng·mL-1脂多糖作用12 h后Nthy-ori 3-1细胞的吞噬功能；荧光探针DCFH-DA法检测0、10、20、100 ng·mL-1脂多糖作用4 h后Nthy-ori 3-1细胞胞内活性氧水平。结果： 与未处理组比较，100 ng·mL-1脂多糖明显促进Nthy-ori 3-1细胞的增殖和提高胞内活性氧的水平（P<0.01），20 ng·mL-1和100 ng·mL-1脂多糖促进Nthy-ori 3-1细胞的吞噬功能（P<0.01和P<0.05），而100 ng·mL-1脂多糖对Nthy-ori 3-1细胞凋亡的影响无统计学意义（P>0.05）。 结论： 脂多糖通过促进TFCs增殖、上调吞噬功能和提高胞内活性氧水平，发挥对TFCs的病理损伤作用,提示脂多糖对桥本甲状腺炎的发生可能有重要作用。

Effects of LPS on the proliferation,phagocytosis and ROSproduction in thyroid follicular cells in vitro

Abstract] Objective: To investigate the effect of lipopolysaccharide(LPS) on the proliferation,apoptosis, phagocytosis and reactive oxygen species(ROS) production in thyroid follicular cells(TFCs) in vitro, and to determine the pathologic damage of TFCs in response to LPS. Methods: Nthy-ori 3-1 cells were incubated with gradient concentrations of 0, 10, 20, 100, 150 ng·mL-1 LPS for 48 h and with 100 ng·mL-1 for 24 h or 48 h, MTT assay was used to measure cell proliferation. Nthy-ori 3-1 cells were treated with 100 ng·mL-1 LPS for 48 h, and flow cytometry was used to measure cell apoptosis. Nthy-ori 3-1 cells were incubated with gradient concentrations of 0, 10, 20, 100 ng·mL-1 LPS for 12 h, and Nile red fluorescent FluoSpheres beads uptake method was used to measure phagocytosis of cells. Nthy-ori 3-1 cells were treated with gradient concentrations of 0, 10, 20, 100 ng·mL-1 LPS for 4 h, and fluorescent probe DCFH-DA was used to measure ROS level of cells. Results: Compared with controls, 100 ng·mL-1 LPS promoted the proliferation and significantly increased the level of ROS of Nthy-ori 3-1 cells(P<0.01). In addition, 20 ng·mL-1 and 100 ng·mL-1 LPS promoted the phagocytic function of Nthy-ori 3-1 cells(P<0.01). However, 100 ng·mL-1 LPS did not increase the apoptosis of Nthy-ori 3-1cells(P>0.05). Conclusion: LPS promoted the pathologic damage of TFCs through up-regulation of the proliferation, phagocytosis and the level of intracellular ROS of TFCs, suggesting that LPS may play an important role in the development of Hashimoto′s thyroiditis. ［Key words］thyroid follicular cells; phagocytosis; lipopolysaccharide; reactive oxygen species