T-2毒素对软骨Ⅱ型胶原蛋白和蛋白聚糖合成的影响以及硒的保护作用

目的探讨T-2毒素对软骨细胞主要间质成分Ⅱ型胶原蛋白和蛋白聚糖合成的影响和硒的保护作用。方法采用MTT法检测T-2毒素对软骨细胞存活率的影响；用TB染色法检测人软骨细胞蛋白聚糖表达；免疫组织化学检测人软骨细胞胶原蛋白Ⅱ表达；RT-PCR检测人软骨细胞Ⅱ型胶原蛋白和蛋白聚糖mRNA表达。结果T-2毒素在浓度为0．001～2mg／L的范围内．对软骨细胞的作用呈较典型的浓度依赖关系和时间依赖关系，而且随着作用时间的延长，浓度依赖关系更加明显。T-2毒素（10～20μg／L）可以抑制软骨细胞Ⅱ型胶原蛋白和蛋白聚糖的合成及其mRNA表达。而加硒能较明显刺激软骨细胞蛋白聚糖mRNA表达，部分减弱T-2毒素的这种抑制，有一定的保护作用，但不显示对T-2毒素引起的Ⅱ型胶原蛋白及其mRNA表达的保护作用。结论T-2毒素对软骨细胞Ⅱ型胶原蛋白和蛋白聚糖合成有明显的抑制作用，微量元素硒对T-2毒素引起的软骨细胞蛋白聚糖改变有一定保护作用。

Protective effect of selenium against T-2 toxin-induced inhibition of chondrocyte aggrecan and collagen Ⅱ synthesis

OBJECTIVE: To study the inhibitory effect of T-2 toxin on the expression of aggrecan and collagen II in chondrocytes and the protection of selenium against this effect. METHODS: Human chondrocytes cultured in vitro were treated with T-2 toxin at different concentrations for varied time periods (1-5 days), and the cell viability was measured by MTT assay. Aggrecan expression was detected by toluidine blue staining and collagen II expression by immunostaining using monoclonal antibody of collagen. Aggrecan and collagen II mRNA expressions were measured by semiquantitative RT-PCR. RESULTS: T-2 toxin dose- and time-dependently affected chondrocyte viability within the concentration range of 0.001-2 mg/L, the prolonged treatment time further enhanced the dose dependence of the inhibitory effect. T-2 toxin lowered aggrecan and collagen II synthesis in the chondrocytes and reduced their mRNA expressions. Selenium could partly attenuate the inhibitory effects of T-2 toxin on aggrecan mRNA expression, but showed no such effect against T-2-induced collagen II expression. CONCLUSION: T-2 toxin can obviously inhibit aggrecan and collagen II synthesis in human chondrocytes, and selenium can partly antagonize the inhibitory effects of T-2 toxin on aggrecan.