Kiełbik Paula, Witkowska-Piłaszewicz Olga
Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland.
Animals (Basel). 2024 Jul 12;14(14):2048. doi: 10.3390/ani14142048.
Canine behavioral disorders have become one of the most common concerns and challenging issues among dog owners. Thus, there is a great demand for knowledge about various factors affecting dogs' emotions and well-being. Among them, the gut-brain axis seems to be particularly interesting, especially since in many instances the standard treatment or behavioral therapies insufficiently improve animal behavior. Therefore, to face this challenge, the search for novel therapeutic methods is highly required. Existing data show that mammals' gut microbiome, immune system, and nervous system are in continuous communication and influence animal physiology and behavior. This review aimed to summarize and discuss the most important scientific evidence on the relationship between mental disorders and gut microbiota in dogs, simultaneously presenting comparable outcomes in humans and rodent models. A comprehensive overview of crucial mechanisms of the gut-brain axis is included. This refers especially to the neurotransmitters crucial for animal behavior, which are regulated by the gut microbiome, and to the main microbial metabolites-short-chain fatty acids (SCFAs). This review presents summarized data on gut dysbiosis in relation to the inflammation process within the organism, as well as the activation of the hypothalamic-pituitary-adrenal (HPA) axis. All of the above mechanisms are presented in this review in strict correlation with brain and/or behavioral changes in the animal. Additionally, according to human and laboratory animal studies, the gut microbiome appears to be altered in individuals with mental disorders; thus, various strategies to manipulate the gut microbiota are implemented. This refers also to the fecal microbiome transplantation (FMT) method, based on transferring the fecal matter from a donor into the gastrointestinal tract of a recipient in order to modulate the gut microbiota. In this review, the possible effects of the FMT procedure on animal behavioral disorders are discussed.
犬类行为障碍已成为犬主们最普遍关注且颇具挑战性的问题之一。因此，对于影响犬类情绪和健康的各种因素的知识需求巨大。其中，肠脑轴似乎特别引人关注，尤其是因为在许多情况下，标准治疗或行为疗法并不能充分改善动物行为。因此，为应对这一挑战，迫切需要寻找新的治疗方法。现有数据表明，哺乳动物的肠道微生物群、免疫系统和神经系统处于持续的交流之中，并影响着动物的生理和行为。本综述旨在总结和讨论关于犬类精神障碍与肠道微生物群之间关系的最重要科学证据，同时呈现人类和啮齿动物模型中的可比结果。文中还对肠脑轴的关键机制进行了全面概述。这尤其涉及到对动物行为至关重要且受肠道微生物群调节的神经递质，以及主要的微生物代谢产物——短链脂肪酸（SCFAs）。本综述呈现了与机体炎症过程相关的肠道菌群失调以及下丘脑 - 垂体 - 肾上腺（HPA）轴激活的汇总数据。上述所有机制在本综述中均与动物的大脑和/或行为变化紧密相关地呈现出来。此外，根据人类和实验动物研究，精神障碍患者的肠道微生物群似乎发生了改变；因此，实施了各种操纵肠道微生物群的策略。这也涉及到粪便微生物群移植（FMT）方法，即基于将供体的粪便物质转移到受体的胃肠道中以调节肠道微生物群。在本综述中，讨论了FMT程序对动物行为障碍可能产生的影响。
