T-2毒素和硒对人软骨蛋白聚糖酶的影响

目的 研究T-2毒素和硒对人软骨蛋白聚糖代谢的影响.方法 体外培养胎儿软骨细胞,根据施加的实验措施将其分为8组,对照组(T-2毒素:0 mg/L,硒:0 mg/L)、1、10、20μg/L T-2毒素组、加硒(0.1mg/L)组、1、10、20 μg/L T-2毒素加硒(0.1 mg/L)组,每组设3个平行样.在T-2毒素和(或)硒作用5d后,采用免疫蛋白印迹法检测软骨细胞蛋白聚糖的蛋白表达水平,用RT-PCR方法检测软骨细胞蛋白聚糖酶-1和蛋白聚糖酶-2的mRNA表达水平.结果 硒、T-2毒素对蛋白聚糖的蛋白表达量、蛋白聚糖酶-1 mRNA表达水平、蛋白聚糖酶-2的mRNA表达水平有影响(F=0.294、27.71,107.45、362.25,34.68、22.26,P均＜0.05),硒与T-2毒素存在交互作用(F=79.99、230.76、388.33,P均＜0.05),表现为拮抗作用.在硒水平为0 mg/L时,1、10、20 μg/L的T-2毒素组蛋白聚糖的蛋白表达(0.278±0.015、0.235±0.029、0.195±0.028)均低于0 mg/L的T-2毒素组(0.472±0.0358,P均＜0.05)；在硒水平为0.1 mg/L时,1、10、20 μg/L的T-2毒素组的蛋白聚糖的蛋白表达(0.399±0.028、0.299±0.020、0.263±0.019)均高于0 mg/L的T-2毒素组(0.197±0.018,P均＜0.05).在T-2毒素分别为1、10、20μg/L时,0.1 mg/L硒组的蛋白聚糖的蛋白表达均高于0 mg/L硒组(P均＜ 0.05).在硒水平为0 mg/L时,1、10、20μg/L的T-2毒素组蛋白聚糖酶-1 mRNA表达(0.535±0.033、1.071±0.043、1.454±0.058)均高于0 mg/L的T-2毒素组(0.481±0.023,P均＜0.05)；在硒水平为0.1 mg/L时,1、10、20μg/L的T-2毒素组的蛋白聚糖酶-1 mRNA表达(1.057±0.048、0.555±0.036、0.902±0.045)均高于0 mg/L的T-2毒素组(0.346±0.020,P均＜0.05).在硒水平为0 mg/L时,1、10、20μg/L的T-2毒素组蛋白聚糖酶-2 mRNA表达(0.596±0.038、0.656±0.033、0.949±0.049)均高于0 mg/L的T-2毒素组(0.387±0.020,P均＜0.05)；在硒水平为0.1 mg/L时,1、10、20μg/L的T-2毒素组的蛋白聚糖酶-2 mRNA表达(0.600±0.040、0.453±0.031、0.164±0.011)均低于0 mg/L的T-2毒素组(1.021±0.046,P均＜0.05)；在T-2毒素分别为10、20μg/L时,0.1 mg/L硒组的蛋白聚糖酶-1和蛋白聚糖酶-2 mRNA表达均低于0 mg/L硒组(P均＜ 0.05).结论 T-2毒素通过上调蛋白聚糖的主要代谢酶蛋白聚糖酶-1和蛋白聚糖酶-2达到降解蛋白聚糖的作用,微量元素硒对T-2毒索引起的软骨细胞蛋白聚糖降解有一定保护作用.

Effects of T-2 toxin and selenium on expression of aggrecanase in human chondrocyte

Objective To determine effects of T-2 toxin and selenium on expression of aggrecanase in human chondrocyte.Methods Human chondrocytes were treated with T-2 toxin(0,1,10,20 μg/L),and/or sodium selenite(final concentration of selenium 0,0.1 mg/L) for 5 days.Aggrecan expression was determined by Western blotting,aggrecanase-1 and aggrecanase-2 mRNA levels were measured by RT-PCR.Results Selenium and T-2 toxin had effects on both aggrecan protein levels and its aggrecanases (include aggrecanase-1 and aggrecanase-2 ) mRNA levels(F =0.294,27.71 for aggrecan,F =107.45,362.25 for aggrecanase-l,F =34.68,22.26 for aggrecanase-2,respectively,all P ＜ 0.05),and there was interaction between selenium and T-2 toxin on aggrecan,aggrecanase-1 and aggrecanase-2 expression(F =79.99,230.76,388.33,all P ＜ 0.05).Furthermore,selenium presented significant antagonism to T-2 toxin on aggrecan,aggrecanase-1 and aggrecanase-2 expression.Aggrecan expression levels(0.278 ± 0.015,0.235 ± 0.029,0.195 ± 0.028,0.399 ± 0.028,0.299 ± 0.020,0.263 ±0.019) induced by both 1,10,20 μg/L T-2 toxin and 0,0.1 mg/L selenium were significantly decreased than the levels(0.472 ± 0.0358,0.197 ± 0.018,all P ＜ 0.05) in control group(0 mg/L toxin).Selenium partially blocked the effects induced by 1,10,and 20 μg/L T-2 toxin(all P＜ 0.05).One,10,20 μg/L T-2 toxin and 0,0.1 mg/L selenium increased both aggrecanase-1 mRNA levels(0.535 ± 0.033,1.071 ± 0.043,1.454 ± 0.058,1.057 ±0.048,0.555 ± 0.036,0.902 ± 0.045) and aggrecanase-2 mRNA levels(0.596 ± 0.038,0.656 ± 0.033,0.949 ±0.049,0.600 ± 0.040,0.453 ± 0.031,0.164 ± 0.011),when compared with control(0.481 ± 0.023,0.346 ±0.020 for aggrecanase-1 and 0.387 ± 0.020,1.021 ± 0.046 for aggrecanase-2,respectively,all P ＜ 0.05).Selenium partially blocked 10,20 μg/L T-2 toxins induced upregulation of aggrecanase-1 (all P ＜ 0.05) and aggrecanase-2 (all P ＜ 0.05 ).Conclusions These data suggest a possible molecular mechanism that T-2 toxin could induce cartilage matrix degradation through the upregulation of aggrecanases expression and enzyme activities.Trace element selenium has some protective effect on cartilage proteoglycan degradation induced by T-2 toxins.