报告题目: Effect of Stress on Intestinal Microbiota and Gut Integrity in Fish

报告人: Rolf Erik Olsen 教授，挪威科技大学(NTNU)鱼类生理学实验室主任/中挪鱼类肠道菌群联合实验室主任

主持人: 杜震宇 教授

报告时间: 2017年4月18日 9:00-9:40 （周二上午）

报告地点: 天美娱乐534报告厅

报告人简介：Olsen教授是挪威科技大学资深教授🫰🏼，任鱼类生理学实验室主任和中挪鱼类肠道菌群联合实验室主任，多年从事鱼类逆境生理学、鱼类肠道健康和脂代谢研究，迄今已发表论文120多篇⏭，H因子达到46，是国际著名的鱼类生理学家。

报告摘要🍩：

The gastro-intestinal tract faces several levels of challenges to homeostasis. While it needs to be highly permeable to nutritional components, it must provide protection against the attack of endogenous digestive enzymes. A stable and dense microbial community is important for proper intestinal functioning, but increased permeability or the establishment of pathogenic agents provides serious threats to the fish health and welfare.

Stressors have many levels of effects on the intestine. Brain-gut pathways include direct effect of stress hormones on the intestine, while gut- brain pathways include cytokine and inflammatory responses (Keightley et al 2015). Release of intestinal mucin is a common response to stress in mammals (Castagliuolo et al. 1996) and fish (Olsen et al 2005). This release participates in a significant alteration of the intestinal microbial community which could increase the probability for establishment of a pathogen (Ringø et al. 2014). Stress also alters the intestinal morphology weakening the junctional complexes (Olsen et al. 2002) and increases intestinal permeability (Olsen et al 2002,2005). The effects may be long lasting even after exposure to single stressors. Increased permeability in rainbow trout following acute stress can last for more than 48h (Olsen et al. 2005), and biochemical alterations like altered content of eicosanoids regulating gut function can last for more than 24h (Olsen et al. 2012, Figure 1). In addition to pathogen threats, altered gut functions can also reduce nutrient utilization and growth as seen in for example subordinate Arctic charr (Olsen et al. 1999).

Functional feeds are an emerging area that can contribute to stabilize the gastrointestinal tract to environmental stressors. The use of probiotics and prebiotics are examples with major potentials in fish. Introducing prebiotics and probiotics may not only boost growth but can also be used to propagate bacterial strains with anti-pathogen properties (e.g. Ringø et al. 2010, Bidhan et al. 2014). 

Simple nutritional modulations using compounds like amino acids or organic acids so also have the potential to optimize gut functions and to support endocrine pathways.