Department of Invertebrate Zoology, St. Petersburg State University, 199034 Universitetskaya Emb. 7/9, St. Petersburg, Russia.
Research Park Centre for Molecular and Cell Technologies, St. Petersburg State University, 199034 Universitetskaya Emb. 7/9, St. Petersburg, Russia.
Parasitol Res. 2024 May 31;123(6):229. doi: 10.1007/s00436-024-08244-8.
The intricate relationships between parasites and hosts encompass a wide range of levels, from molecular interactions to population dynamics. Parasites influence not only the physiological processes in the host organism, but also the entire ecosystem, affecting mortality of individuals, the number of offspring through parasitic castration, and matter and energy cycles. Understanding the molecular mechanisms that govern host-parasite relationships and their impact on host physiology and environment remains challenging. In this study, we analyzed how infection with Microphallus trematodes affects the metabolome of two Littorina snail species inhabiting different intertidal zone shore levels. We applied non-targeted GC-MS-based metabolomics to analyze biochemical shifts induced by trematode infection in a host organism. We have identified changes in energy, amino acid, sugar, and lipid metabolism. In particular, we observed intensified amino acid catabolism and nitrogenous catabolites (glutamine, urea) production. These changes primarily correlated with infection and interspecies differences of the hosts rather than shore level. The changes detected in the host metabolism indicate that other aspects of life may have been affected, both within the host organism and at a supra-organismal level. Therefore, we explored changes in microbiota composition, deviations in the host molluscs behavior, and acetylcholinesterase activity (ACE, an enzyme involved in neuromuscular transmission) in relation to infection. Infected snails displayed changes in their microbiome composition. Decreased ACE activity in snails was associated with reduced mobility, but whether it is associated with trematode infection remains unclear. The authors suggest a connection between the identified biochemical changes and the deformation of the shell of molluscs, changes in their behavior, and the associated microbiome. The role of parasitic systems formed by microphallid trematodes and Littorina snails in the nitrogen cycle at the ecosystem level is also assumed.
寄生虫与宿主之间的复杂关系涵盖了广泛的层次，从分子相互作用到种群动态。寄生虫不仅影响宿主生物体的生理过程，还影响整个生态系统，影响个体死亡率、寄生虫去势导致的后代数量以及物质和能量循环。理解控制宿主-寄生虫关系的分子机制及其对宿主生理和环境的影响仍然具有挑战性。在这项研究中，我们分析了感染 Microphallus 吸虫如何影响栖息在不同潮间带海岸水平的两种扁玉螺物种的代谢组。我们应用基于非靶向 GC-MS 的代谢组学来分析寄生虫感染对宿主生物体生化变化的影响。我们已经确定了能量、氨基酸、糖和脂质代谢的变化。特别是，我们观察到氨基酸分解代谢和含氮分解产物（谷氨酰胺、尿素）的产生加剧。这些变化主要与感染和宿主的种间差异有关，而与潮位无关。宿主代谢中检测到的变化表明，其他方面的生命可能受到了影响，无论是在宿主生物体内部还是在超生物体水平上。因此，我们探索了微生物群落组成的变化、宿主软体动物行为的偏差以及与感染相关的乙酰胆碱酯酶活性（ACE，一种参与神经肌肉传递的酶）。感染的蜗牛表现出微生物群落组成的变化。蜗牛的 ACE 活性降低与移动性降低有关，但这是否与吸虫感染有关尚不清楚。作者提出了所确定的生化变化与软体动物壳变形、行为变化以及相关微生物群落之间的联系。还假设了微球蚴吸虫和扁玉螺形成的寄生系统在生态系统水平上对氮循环的作用。
