Henan Key Laboratory of Environmental and Animal Product Safety, Henan University of Science and Technology, Kaiyuan Avenue 263, Luoyang, 471003, Henan, People's Republic of China.
Biol Trace Elem Res. 2020 Sep;197(1):115-122. doi: 10.1007/s12011-019-01967-1. Epub 2020 Jan 25.
The role of pro-inflammatory cytokines in the toxicity of fluoride to tumor cells was investigated by culturing Hepa1-6 cells in medium containing gradient concentrations of fluoride (0, 0.5, 1, 1.5, 2, 3, 4, and 5 mmol/L). The viability of Hepa1-6 cells was detected via MTT assay. Interleukin (IL)-2, IL-6, tumor necrosis factor (TNF)-α, and IL-1β levels in the supernatant were determined via an enzyme-linked immunosorbent assay, and the protein expression levels of these enzymes in Hepa1-6 cells were evaluated by immunofluorescence staining. Results showed that the viability of Hepa1-6 cells remarkably decreases after fluoride exposure, especially at concentration of 3, 4, and 5 mmol/L fluoride. Levels of IL-2, TNF-α, and IL-1β in the supernatant markedly decreased when cells were exposed to fluoride at concentrations of 1 mmol/L or higher. However, levels of TNF-α and IL-1β substantially increased and IL-2 showed no remarkable change when the fluoride concentration was 0.5 mmol/L. The content of IL-6 remarkably increased with increasing fluoride concentrations up to 2 mmol/L, and then markedly decreased at 3, 4, and 5 mmol/L fluoride; the decreasing trend of IL-6 content under high fluoride exposure is consistent with the decrease in Hepa1-6 cell viability observed at the same concentration. The protein expression levels of IL-2, IL-6, TNF-α, and IL-1β were in accordance with their contents in the supernatant. In summary, our study demonstrated that fluoride inhibits Hepa1-6 cell growth and results in disorders in the expression and secretion pro-inflammatory cytokines.
采用含不同浓度氟化物（0、0.5、1、1.5、2、3、4 和 5 mmol/L）的培养液培养 Hepa1-6 细胞，研究促炎细胞因子在氟化物对肿瘤细胞毒性中的作用。采用 MTT 法检测 Hepa1-6 细胞活力。酶联免疫吸附试验检测上清液中白细胞介素（IL）-2、IL-6、肿瘤坏死因子（TNF）-α和 IL-1β水平，免疫荧光染色法评价 Hepa1-6 细胞中这些酶的蛋白表达水平。结果显示，氟化物暴露后 Hepa1-6 细胞活力显著下降，尤其是在 3、4 和 5 mmol/L 氟化物浓度下。当细胞暴露于 1 mmol/L 或更高浓度的氟化物时，上清液中 IL-2、TNF-α和 IL-1β水平显著降低。然而，当氟化物浓度为 0.5 mmol/L 时，TNF-α和 IL-1β水平显著增加，而 IL-2 没有明显变化。随着氟化物浓度的增加，IL-6 含量显著增加，直至 2 mmol/L，然后在 3、4 和 5 mmol/L 氟化物时显著降低；在相同浓度下，高氟暴露下 IL-6 含量的下降趋势与 Hepa1-6 细胞活力的下降一致。IL-2、IL-6、TNF-α和 IL-1β的蛋白表达水平与上清液中的含量一致。综上所述，本研究表明氟化物抑制 Hepa1-6 细胞生长，并导致促炎细胞因子表达和分泌紊乱。
