Institute of Endemic Diseases, School of Public Health of Health Science Center, Xi'an Jiaotong University, Key Laboratory of Trace Elements and Endemic Diseases, National Health and Family Planning Commission, Xi'an 710061, China.
Hospital for Special Surgery, Weill Cornell Medical College, New York, NY, USA.
J Trace Elem Med Biol. 2017 Dec;44:218-224. doi: 10.1016/j.jtemb.2017.08.009. Epub 2017 Aug 12.
To explore the metabolism of T-2 toxin in human chondrocytes (HCs) and determine the impact of selenium supplementation. For determination of cytotoxicity using the MTT assay, optical density values were read with an automatic enzyme-linked immunosorbent assay reader at 510nm. Cell survival was calculated and the cytotoxicity estimated. To identify the metabolites of T-2 toxin, the medium supernatants and C28/I2 cells were analyzed by high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) separately. For HPLC-MS/MS, the mobile phase A was water and phase B was 98% methanol. The gradient for the elution was: 0-0.5min, 50% of B; 0.5-2.0min, 100% of B; 2.0-3.5min, 100% of B; 3.6-6min, 50% of B. T-2 toxin increased the toxicity to C28/I2 cells significantly in a dose- and time-dependent manner (viability range 91.5-22.0%). Supplementation with selenium (100ng/mL) could increase the cell viability after the 24h incubation. The concentration of T-2 toxin in the cell medium decreased from 20 to 6.67±1.02ng/mL, and the concentration of HT-2 toxin increased from 0 to 6.88±1.23ng/mL during the 48h incubation, whereas the relative concentration of T-2 toxin in cells increased from 0 to 12.80±1.84ng/g. Supplementary selenium in the HCs cultures reduced the cytotoxicity induced by T-2 toxin significantly, and was associated with rapid conversion of T-2 toxin in the culture medium to HT-2 toxin. T-2 toxin was more toxic to HCs than HT-2 toxin at equivalent concentrations. HT-2 toxin was a detectable metabolite of T-2 toxin in cultured HCs, and selenium enhanced the metabolic conversion of T-2 toxin, reducing its cytotoxicity to HCs.
探讨 T-2 毒素在人软骨细胞（HCs）中的代谢情况，并确定硒补充的影响。采用 MTT 法测定细胞毒性，在 510nm 处用自动酶联免疫吸附测定读取吸光度值。计算细胞存活率并估计细胞毒性。为了鉴定 T-2 毒素的代谢物，分别通过高效液相色谱串联质谱（HPLC-MS/MS）分析培养基上清液和 C28/I2 细胞。对于 HPLC-MS/MS，流动相 A 为水，相 B 为 98%甲醇。洗脱梯度为：0-0.5min，B 为 50%；0.5-2.0min，B 为 100%；2.0-3.5min，B 为 100%；3.6-6min，B 为 50%。T-2 毒素以剂量和时间依赖的方式显著增加 C28/I2 细胞的毒性（活力范围 91.5-22.0%）。24 小时孵育后，硒（100ng/mL）的补充可提高细胞活力。细胞培养基中 T-2 毒素的浓度从 20ng/mL 降低到 6.67±1.02ng/mL，48 小时孵育期间 HT-2 毒素的浓度从 0ng/mL 增加到 6.88±1.23ng/mL，而细胞中 T-2 毒素的相对浓度从 0ng/g 增加到 12.80±1.84ng/g。HCs 培养物中补充的硒可显著降低 T-2 毒素诱导的细胞毒性，并与培养基中 T-2 毒素向 HT-2 毒素的快速转化有关。在等效浓度下，T-2 毒素对 HCs 的毒性大于 HT-2 毒素。HT-2 毒素是培养的 HCs 中 T-2 毒素的可检测代谢物，而硒增强了 T-2 毒素的代谢转化，降低了其对 HCs 的细胞毒性。
