产毒水华蓝藻胁迫下铜锈环棱螺的代谢响应机制研究

The theoretical problem in ecotoxicological studies of bloom-forming cyanobacteria and their toxins to aquatic organisms - - molecular response mechanism of animal to microcystins (MCs) is not yet clear. In order to answer the above question, this subject will be carried out the research on the accumulation of total MCs (bound and free MCs), the dynamic of metabolites and metabolic response mechanism in vertebrates. based on the animal model of Gastropoda Bellamya aeruginosa from pilot study, the content of the two-state MCs in two tissues of snail will be monitored after fed with toxic Microcystis aeruginosa. Using NMR-based metabolomics technology, the differences of the endogenous metabolites in snails between two treatments fed with the different toxigenic characteristics Microcystis aeruginosa will be analyzed, the dynamic pattern of metabonomics over time will be studied. metabolic response mechanism of snails to the MCs stress and related metabolites will be revealed, and the dynamic distribution of the two-state MCs in different tissues will be cleared at the same time. The results are expected to further enrich the achievement of interaction between bloom-forming cyanobatrica and gastropods, as well as providing a theoretical basis for screening the ideal species of biomonitor.

本项目针对水华蓝藻及其毒素对水生生物的生态毒理学研究中尚未明晰的理论问题- - 动物对微囊藻毒素（MCs）的分子响应机制，开展无脊椎动物体内总MCs负荷（结合态和非结合态MCs）、代谢物动态及代谢响应机制研究。以课题组现有淡水腹足纲模型动物,铜锈环棱螺为研究对象，在投喂产毒铜绿微囊藻后监测两态MCs在螺两种组织中的含量变化。在此基础上采用基于核磁共振的代谢组学技术，比较分析螺在投喂不同产毒特性铜绿微囊藻后其内源性代谢产物的差异，研究代谢组随时间的动态变化模式。旨在揭示螺类在受到MCs 胁迫时的代谢响应机制及相关的代谢产物，同时明晰不同组织内两态MCs的动态分布情况。丰富腹足纲动物与水华蓝藻间的相互作用的研究成果，为筛选理想的生物监测物种提供理论依据。

研究发现虽然投喂不产毒铜绿微囊藻处理组中铜锈环棱螺组织均未检出MCs的存在,但肝胰脏和性腺中检测到了MCs的存在，且在性腺中无论非结合态还是结合态毒素含量都低于同期肝胰脏中的含量。而在鳃、外套膜和腹足肌肉中没有检出MCs。虽然没有观察到不同处理间铜锈环棱螺肌肉代谢物表现出显著差异，但是微囊藻毒素（MCs）暴露能够显著提高螺肝胰脏中的多种氨基酸（亮氨酸、异亮氨酸、苏氨酸、丙氨酸、谷氨酸、蛋氨酸、肌氨酸、天冬氨酸和赖氨酸等）、有机酸（乳酸、乙酸和D-3 -羟基丁酸）和胆碱类物质（胆碱、磷酸胆碱和甘油磷酸胆碱）的水平。MCs的暴露可能导致螺肝胰脏能量耗尽，并严重的干扰了动物的脂类和细胞膜结构代谢、蛋白质合成和能量代谢。代谢紊乱还会随毒素的积累而逐步恶化。同时MCs的暴露也会使三角帆蚌也产生相似的代谢响应。此外还利用高通量测序方法建立了三角帆蚌转录组数据库。目前，本课题的实验内容已全部完成，并在SCI期刊发表论文2篇，在中文核心期刊发表论文5篇，参加学术会议2次，培养研究生2名。