脱氧雪腐镰刀菌烯醇对小鼠胸腺细胞凋亡和增殖的影响

Effects of deoxynivalenol on apoptosis and proliferation of mouse thymocytes in vivo

目的 :探讨脱氧雪腐镰刀菌烯醇 (DON)对小鼠胸腺细胞凋亡和增殖的影响。方法 :以动物实验、形态学观察、DNA琼脂糖凝胶电泳、流式细胞术方法研究了不同剂量DON对小鼠胸腺细胞凋亡和增殖的影响及其量效关系。结果 :FCM检测结果表明 ,不同浓度DON均能诱导并促进体内小鼠胸腺细胞凋亡 ,DON 0 5mg/kg、1mg/kg、2mg/kg、4mg/kg、8mg/kg组胸腺细胞的平均凋亡百分率分别为 6 35 %± 1 30 %、8 30 %± 1 33%、8 89%± 2 15 %、10 70 %± 0 6 2 %和 12 5 4 %± 2 0 8% ,在 0 5mg/kg到 8mg/kg的浓度范围内 ,随DON浓度的增高 ,胸腺细胞的凋亡率也相应增高 ,两者呈显著正相关 (r=0 788,P <0 0 1)。DNA琼脂糖凝胶电泳结果显示 ,大剂量 (8mg/kg和 4mg/kg)DON处理组小鼠胸腺细胞出现了凋亡特有的梯状条带。超微结构观察可见DON处理组小鼠胸腺部分细胞出现核染色质固缩凝聚、胞芽等细胞凋亡的超微结构特征表现。大剂量 (8mg/kg和 4mg/kg)DON可明显降低小鼠胸腺细胞增殖活性 (用PI表示 ,P <0 0 1)。结论 :脱氧雪腐镰刀菌烯醇可剂量依赖地诱导并促进小鼠胸腺细胞的凋亡和抑制其增殖。

AIM: To explore the effect of deoxynivalenol on apoptosis and proliferation of mouse thymocytes in vivo. METHODS: Effect of deoxynivalenol at different concentrations on apoptosis and proliferation of mouse thymocytes in vivo were studied with animal experiment, electron microscopic observation, DNA agarose gel electrophoresis and flow cytometric analyses. RESULTS: FCM analysis showed that the apoptosis rates of the thymocytes in DON groups (0 5 mg/kg, 1 mg/kg, 2 mg/kg, 4 mg/kg and 8 mg/kg) were significantly higher than that in control ( P< 0 01). In the concentration ranging from 0 5 mg/kg to 8 mg/kg, a significant dose-dependant response correlation could be found between apoptosis rate and DON concentration. The result of DNA agarose gel electrophoresis showed that characteristic DNA ladder was found in groups treated DON at relatively higher concentrations (8 mg/kg and 4 mg/kg). Ultrastructurally, chromatin condensation and nuclear budding phenomenon could be found in the cells treated with DON. In addition to the effects on apoptosis, 4 mg/kg and 8 mg/kg DON treatment could significantly decrease the PIs of the treated thymocytes in vivo as compared with control. CONCLUSION:DON can induce and enhance murine thymocytes apoptosis in a dose-dependant manner and inhibit the proliferation activities of the treated cells.