School of Marine Sciences, Ningbo University, Ningbo, 315211, China; Collaborative Innovation Center for Zhejiang Marine High-Efficiency and Healthy Aquaculture, Ningbo, 315211, China.
School of Marine Sciences, Ningbo University, Ningbo, 315211, China.
Fish Shellfish Immunol. 2018 Sep;80:191-199. doi: 10.1016/j.fsi.2018.05.040. Epub 2018 May 24.
Aquatic animals are frequently suffered from starvation due to restricted food availability or deprivation. It is currently known that gut microbiota assists host in nutrient acquisition. Thus, exploring the gut microbiota responses would improve our understanding on physiological adaptation to starvation. To achieve this, we investigated how the gut microbiota and shrimp digestion and immune activities were affected under starvation stress. The results showed that the measured digestion activities in starved shrimp were significantly lower than in normal cohorts; while the measured immune activities exhibited an opposite trend. A structural equation modeling (SEM) revealed that changes in the gut bacterial community were directly related to digestive and immune enzyme activities, which in turn markedly affected shrimp growth traits. Notably, several gut bacterial indicators that characterized the shrimp nutrient status were identified, with more abundant opportunistic pathogens in starved shrimp, although there were no statistical differences in the overall diversity and the structures of gut bacterial communities between starved and normal shrimp. Starved shrimp exhibited less connected and cooperative interspecies interaction as compared with normal cohorts. Additionally, the functional pathways involved in carbohydrate and protein digestion, glycan biosynthesis, lipid and enzyme metabolism remarkably decreased in starved shrimp. These attenuations could increase the susceptibility of starved shrimp to pathogens infection. In summary, this study provides novel insights into the interplay among shrimp digestion, immune activities and gut microbiota in response to starvation stress.
水生动物常因食物有限或缺乏而遭受饥饿。目前已知肠道微生物群有助于宿主获取营养。因此，探索肠道微生物群的反应将有助于我们更好地理解饥饿对生理的适应。为了实现这一目标，我们研究了在饥饿胁迫下，肠道微生物群和虾的消化和免疫活动是如何受到影响的。结果表明，饥饿虾的测量消化活性明显低于正常虾群；而测量的免疫活性则呈现相反的趋势。结构方程模型（SEM）表明，肠道细菌群落的变化与消化和免疫酶活性直接相关，而这些酶活性又显著影响虾的生长特征。值得注意的是，鉴定出了一些能够描述虾营养状况的肠道细菌指标，在饥饿的虾中，机会致病菌更为丰富，尽管饥饿和正常虾的肠道细菌群落的整体多样性和结构没有统计学差异。与正常虾群相比，饥饿的虾表现出较少的种间相互作用的连接和协作。此外，参与碳水化合物和蛋白质消化、聚糖生物合成、脂质和酶代谢的功能途径在饥饿的虾中显著减少。这些衰减会增加饥饿虾对病原体感染的易感性。总之，本研究为虾在饥饿应激下消化、免疫活动和肠道微生物群之间的相互作用提供了新的见解。
