赤子爱胜蚓对不同浓度四溴双酚A代谢的急性与亚急性毒性响应

Metabolic responses of Eisenia fetida after both acute and sub-lethal exposure to different concentrations of Tetrabromobisphenol A

运用核磁共振一维氢谱研究不同浓度四溴双酚A(TBBPA)急性暴露与亚急性暴露对赤子爱胜蚓(Eisenia fetida)的代谢影响.通过设置不同剂量TBBPA进行急性暴露和亚急性暴露,运用正交偏最小二乘投影分析法(OPLS)比较急性和亚急性暴露下蚯蚓的代谢差异,研究蚯蚓代谢水平与暴露剂量的关系,以找出差异代谢物作为TBBPA毒性效应的代谢标志物.结果表明,急性暴露和亚急性暴露均能很好地区分不同剂量染毒组间的代谢差异,且TBBPA暴露剂量越大,蚯蚓体内代谢与空白组的差异越大.急性暴露和亚急性暴露后,亮氨酸、赖氨酸和甜菜碱等代谢物剂量随TBBPA剂量增加的变化趋势是一致的,亚急性暴露中的变化幅度大于急性暴露.TBBPA暴露剂量为100 mg·kg^(-1)时,赤子爱胜蚓受到毒害作用,体内代谢物变化显著,代谢平衡遭到破坏,差异代谢物对毒性效应的指示作用比较敏感.甜菜碱、亮氨酸和赖氨酸可作为标志性代谢物揭示TBBPA对赤子爱胜蚓在渗透压调节、能量供给以及免疫功能方面的毒性效应,为进一步探索TBBPA毒性机理提供理论基础.

In this paper,both acute and sub-lethal exposure of earthworm Eisenia fetida to Tetrabromobisphenol A（ TBBPA） were investigated using1 H NMR metabolomics. Metabolic responses of both acute and sub-lethal exposure were investigated using orthogonal partial least-squares discriminant analysis（ OPLS） in order to find out metabolic markers of TBBPA toxicity. The results show that,metabolic differences between different concentrations of TBBPA were significant in both acute and sub-lethal exposures compared to the blank group,and the greater of the concentration of TBBPA,the more significant the difference. Trends of most metabolites such as leucine,lysine and betaine in acute and sub-lethal exposures were consistent,while the change in sub-lethal exposure was much greater. The experiment results also show that when exposure concentration of TBBPA reached 100 mg·kg^-1,metabolites changed significantly and metabolic balance of earthworms was destroyed,so metabolites were sensitive for indicating toxicity of TBBPA.Betaine,leucine,lysine could be taken as metabolic markers for TBBPA toxicity on osmoregulation,energy supply and immune function. This research provides theoretical basis for further studies of TBBPA toxicity mechanism.