A next generation probiotic,Akkermansia muciniphila

Abstract

Akkermansia muciniphila, a symbiotic bacterium of the mucus layer, can utilize mucin as its sole carbon, nitrogen, and energy source. As an abundant resident in the intestinal tract of humans and animals, the probiotic effects of A. muciniphila including metabolic modulation, immune regulation and gut health protection, have been widely investigated. Various diseases such as metabolic syndromes and auto-immnue diseases have been reported to be associated with the disturbance of the abundance of A. muciniphila. In this review, we describe the biological characterization of A. muciniphia, the factors that influence its colonization of the intestinal tract; and discuss the current state of our knowledge on its role in host health and disease.     

Akkermansia muciniphila的分离培养及其在不同人群的定植比较研究进展

Akkermansia muciniphila是定植在胃肠道黏液层的可特异性降解黏蛋白的革兰氏阴性严格厌氧菌,最先从 人体粪便中分离得到。A. muciniphila在宿主内腔黏膜表面充当重要角色,调节机体健康,近年来逐渐成为肠道微生 态和益生菌研究热点。本文针对A. muciniphila最新的基因组信息及其分子生物学鉴定、分型技术以及菌株分离与纯 化技术进行综述,探讨了现有的A. muciniphila培养条件、分离和纯化方法的优缺点,比较其在不同人群肠道定植的差 异性,旨在分析菌群移植的可能性,从而深入研究A. muciniphila的分子作用机制,以期实现新型益生菌的开发。     

嗜黏蛋白阿克曼氏菌对高尿酸血症小鼠血清尿酸及组织炎症的影响及机制

目的：研究活的和巴氏杀菌处理的嗜黏蛋白阿克曼氏菌（Akkermansia muciniphila）对高尿酸血症小鼠血清尿酸水平及组织炎症的影响和潜在机制。方法：使用氧嗪酸钾和次黄嘌呤联合含20%（以体系质量计）酵母膏的饲料对ICR小鼠进行为期3周的高尿酸血症造模,同时分别灌胃活的和巴氏杀菌处理的嗜黏蛋白阿克曼氏菌作为处理组,采集小鼠血液和组织样品,测定小鼠血清尿酸浓度以及肝脏黄嘌呤氧化酶活力,并通过苏木精-伊红染色法进行小鼠肾和肠道病理分析。结果：不同形式的嗜黏蛋白阿克曼氏菌均能一定程度地降低小鼠血清尿酸浓度。肝脏黄嘌呤氧化酶活力检测以及蛋白印迹分析结果表明两种形式的嗜黏蛋白阿克曼氏菌能下调该酶活性及蛋白表达,从而减少肝脏尿酸的生成。肾和肠道组织病理分析结果表明模型组小鼠肾脏和肠道均有损伤,包括肾小球萎缩、肾间质炎性细胞浸润以及肠绒毛变短,嗜黏蛋白阿克曼氏菌处理能减轻这些症状。嗜黏蛋白阿克曼氏菌干预还能下调肾脏及肠道Toll样受体4和Caspase 1水平,从而抑制白细胞介素-1β表达,有效缓解小鼠脏器中的炎症反应。结论：嗜黏蛋白阿克曼氏菌能用于改善小鼠高尿酸血症,并且巴氏杀菌处理后的...     

多酚对肠道微生物影响的研究进展及对多酚指示菌的探讨

肠道微生物近年来越来越受到人们重视,它们不仅数量庞大而且与宿主的健康息息相关。肠道微生物生态平衡的紊乱会导致肥胖、炎症、胰岛素抵抗甚至是精神性疾病。多酚类物质是重要的植物源功能性成分,许多研究表明多酚可以调节肠道微生物的生态平衡,改善其结构组成。现基于国内外多酚对肠道微生物影响的研究,总结了对多酚敏感的肠道菌,发现双歧杆菌(Bifidobacterium)、乳杆菌属(Lactobacillus)、Akkermansia muciniphila(简称A.muciniphila)等有成为多酚指示菌的潜质。希望本文能够为未来多酚对肠道微生物生态平衡影响的研究提供新思路。     

Ⅱ型糖尿病与肠道菌群及益生菌的相关性研究进展

Ⅱ型糖尿病是一种常见的慢性代谢性疾病,其发病机制十分复杂,其中肠道菌群在其发病早期和加重过程中都起着重要的作用。益生菌作为调节肠道菌群的有效手段,可以通过改善肠道通透性、调节血脂、增强机体免疫力等多种机制对II型糖尿病起到预防和改善作用。现就近年来肠道菌群和2型糖尿病的相关性以及益生菌的作用研究进展作一综述。     

Effects of deep frying vegetable oils rich in PUFAs on gut microbiota in rats

Vegetable oils rich in PUFAs are widely used in daily cooking and food industry, and PUFAs could be utilised by gut microbiota and present prebiotic effects. However, PUFAs are unstable in high-temperature cooking like frying. In the current study, we aimed to explore the influence of thermally oxidised oils rich in PUFA on gut microbiota. Two vegetable oils: omega-3 alpha-linolenic acid (ALA)-rich perilla oil or omega-6 linoleic acid-rich sunflower oil were heated at 180 °C for 10 h, and then fed to male SD rats for 14 weeks. Administration of heated perilla oil dramatically increased the relative abundance of Akkermansia muciniphila, a recent identified probiotics which may weaken intestinal mucus barrier, and inhibited the expression of several tight junction-related genes including occludin and claudin-1 in colon. Consumption of thermally oxidised sunflower oil stimulated the proliferation of Bifidobacterium. Our findings suggested that thermally processing has complicated effects on the prebiotic effects of vegetable oils rich in PUFAs, and perilla oil fried foods may be potential sources to stimulate Akkermansia proliferation in gut.     

肠道菌群微生态平衡与人体健康的研究进展

人体肠道微生物种类繁多且数量庞大。正常肠道菌群作为人体的天然屏障,对维持人体健康起着重要的作用。机体内外环境的变化可影响肠道菌群的结构,造成肠道菌群失衡,继而引发或加重疾病,影响人体健康。通过膳食补充益生菌和益生元,选择性地剌激和调节肠道菌群的数量和组成,保持肠道菌群的微生态平衡,是预防和治疗疾病,促进人体健康的有效措施。本文综述了国内外关于肠道菌群的组成及功能、与相关疾病及治疗的关系以及维持肠道微生态平衡的措施。      

Influence of functional food components on gut health

Intestinal epithelial cells (IECs) lining the gastrointestinal tract establish a barrier between external environments and the internal milieu. An intact intestinal barrier maintains gut health and overall good health of the body by preventing from tissue injury, pathogen infection and disease development. When the intestinal barrier function is compromised, bacterial translocation can occur. Our gut microbiota also plays a fundamentally important role in health, for example, by maintaining intestinal barrier integrity, metabolism and modulating the immune system, etc. Any disruption of gut microbiota composition (also termed dysbiosis) can lead to various pathological conditions. In short, intestinal barrier and gut microbiota are two crucial factors affecting gut health. The gastrointestinal tract is a complex environment exposed to many dietary components and commensal bacteria. Dietary components are increasingly recognized to play various beneficial roles beyond basic nutrition, resulting in the development of the functional food concepts. Various dietary modifiers, including the consumption of live bacteria (probiotics) and ingestible food constituents such as prebiotics, as well as polyphenols or synbiotics (combinations of probiotics and prebiotics) are the most well characterized dietary bioactive compounds and have been demonstrated to beneficially impact the gut health and the overall well-being of the host. In this review we depict the roles of intestinal epithelium and gut microbiota in mucosal defence responses and the influence of certain functional food components on the modulation of gut health, with a particular focus on probiotics, prebiotics and polyphenols.     

A critical review on diet-induced microbiota changes and cardiovascular diseases

Abstract

Background: Cardiovascular diseases (CVDs) commonly denote the disorders that generally occur as a result of unhealthy food habits. Heart failure, cerebrovascular illness, rheumatic heart disease are the common CVDs. The prevalence of CVD is increased considerably in recent decades upon unhealthy food habits and varied alternative factors such as diabetes, smoking and excessive use of alcohol. A change into a healthy food habit can reverse the strategy during a course of time.

Objectives of the study: The objective of this review is to summarize the research findings and elaborate the relationship between the diet, gut microbiota, and CVD.

Results: The dietary products containing the least saturated, trans-fat and cholesterol have the tendency to scale back the burden of CVDs, for instance, vegetables and fruits. The potential reason for the cardioprotective activity of the diet ought to be its high-unsaturated fatty acid composition and less saturated fat. Recent studies have found that gut microbiota plays a key role in mediating disease prevention. The metabolism of dietary products into varied bioactive metabolites is regulated by gut microbiota. The contributory role of gut microbiota in dietary metabolism and CVD prevention studies are increasing with promising outcomes.

Conclusion: Hence, the review was proposed to reach the researchers within this field of study and share the available knowledge in gut microbiota-mediated CVD prevention. In our current review, we have updated all the research findings within the field of diet-mediated cardiovascular prevention through gut microbiota.     

肠道菌群与食物过敏性疾病研究进展

食物过敏作为食品安全的热点问题在全球引起了广泛关注,食物过敏发病率的不断增加与肠道菌群结构和功能的变化密切相关。生活环境和膳食结构的改变、抗生素的使用等诸多因素都可引起肠道菌群失衡,而肠道菌群丰度和多样性的变化可导致肠道菌群与宿主免疫系统相互作用的变化,从而破坏口服耐受增加食物过敏的发病率。近年来随着肠道菌群-宿主相互作用等相关研究的不断深入,调整肠道菌群结构为过敏性疾病的防治提供了新的思路,因而益生菌在预防和治疗食物过敏中的作用开始备受关注。本文首先从细胞和分子水平总结了口服耐受和食物过敏的产生的相关机理,进一步综述了目前对于肠道菌群通过与宿主黏膜免疫系统相互作用调节食物过敏的相关机制研究,并探讨益生菌防治食物过敏的潜在机理,以期为益生菌在预防和治疗食物过敏中的应用提供理论依据。     

肠道微生物调控肠道肿瘤的相关性研究进展

肠道微生物与肿瘤的发生发展密切相关,一直是基础医学、生物学和食品安全等多个领域的研究热点。由于肠道微生物的种类、机体肿瘤类型及其研究方法多样化,所以目前肠道微生物与肿瘤的关系尚未完全明晰。文章对近几年国内外关于肠道微生物与肿瘤发生抑制的关系及其分子机理等相关研究文献进行了梳理,以期为肠道微生物防治肿瘤提供参考。      

肠道菌群利用膳食纤维及其与人体健康关系研究进展

膳食纤维具有提供能量、增强机体免疫的功能,对于人体健康至关重要,被营养学界认定为与蛋白质、脂肪、碳水化合物、维生素、矿物质与水并列的第7类营养素。肠道菌群能激活和维持人的免疫系统和新陈代谢的稳定性,肠道菌群的稳态对人体的发育和成熟至关重要。肠道菌群能够消化膳食纤维,二者之间存在着复杂的相互作用,共同促进和维持肠道健康。近年来,膳食纤维与肠道菌群之间的相互作用受到了科学家广泛关注并取得很大进展。该文就膳食纤维、肠道菌群及其与人体健康关系的研究现状进行了回顾和展望,为深入了解膳食纤维对人体的作用,合理调整膳食结构,促进肠道健康提供参考。     

膳食纤维通过调节肠道微生物及其代谢产物对动脉粥样硬化的影响研究进展

膳食纤维是一种不可被消化和吸收的碳水化合物聚合物,能够通过调节肠道微生物群的生长,促进肠道微生物区系的动态平衡,进而影响肠道微生物代谢产物如脂多糖、三甲胺N-氧化物、短链脂肪酸和胆汁酸的产生,达到调节宿主生理健康的目的.动脉粥样硬化是一种慢性炎症性疾病,其发生发展与脂质代谢紊乱和炎症反应关系密切.而肠道微生物及其代谢产...     

Dietary pectic substances enhance gut health by its polycomponent: A review

Pectic substances, one of the cell wall polysaccharides, exist widespread in vegetables and fruits. A surge of recent research has revealed that pectic substances can inhibit gut inflammation and relieve inflammatory bowel disease symptoms. However, physiological functions of pectins are strongly structure dependent. Pectic substances are essentially heteropolysaccharides composed of homogalacturonan and rhamnogalacturonan backbones substituted by various neutral sugar sidechains. Subtle changes in the architecture of pectic substances may remarkably influence the nutritional function of gut microbiota and the host homeostasis of immune system. In this context, developing a structure–function understanding of how pectic substances have an impact on an inflammatory bowel is of primary importance for diet therapy and new drugs. Therefore, the present review has summarized the polycomponent nature of pectic substances, the activities of different pectic polymers, the effects of molecular characteristics and the underlying mechanisms of pectic substances. The immunomodulated property of pectic substances depends on not only the chemical composition but also the physical structure characteristics, such as molecular weight (M_w) and chain conformation. The potential mechanisms by which pectic substances exert their protective effects are mainly reversing the disordered gut microbiota, regulating immune cells, enhancing barrier function, and inhibiting pathogen adhesion. The manipulation of pectic substances on gut health is sophisticated, and the link between structural specificity of pectins and selective regulation needs further exploration.     

Understanding the gut microbiome of dairy calves: Opportunities to improve early-life gut health

Early gut microbiota plays a vital role in the long-term health of the host. However, understanding of these microbiota is very limited in livestock species, especially in dairy calves. Neonatal calves are highly susceptible to enteric infections, one of the major causes of calf death, so approaches to improving gut health and overall calf health are needed. An increasing number of studies are exploring the microbial composition of the gut, the mucosal immune system, and early dietary interventions to improve the health of dairy calves, revealing possibilities for effectively reducing the susceptibility of calves to enteric infections while promoting growth. Still, comprehensive understanding of the effect of dietary interventions on gut microbiota—one of the key aspects of gut health—is lacking. Such knowledge may provide in-depth understanding of the mechanisms behind functional changes in response to dietary interventions. Understanding of host–microbial interactions with dietary interventions and the role of the gut microbiota during pathogenesis at the site of infection in early life is vital for designing effective tools and techniques to improve calf gut health.     

膳食组分与膳食模式对肠道微生物的影响研究进展

肠道微生物在人体内形成复杂的微观生态系统,能够对机体健康产生显著影响。膳食因素可以塑造肠道微生物,影响肠道微生物发挥功能。在此前的综述中,主要聚焦在膳食脂肪、膳食蛋白质、膳食碳水与高丰度菌门的相关研究,忽视了食品添加剂、功能性物质等膳食因素对于肠道微生物的影响,也少有聚焦于低丰度关键微生物的研究。本文综述了近年来有关膳食与肠道微生物的研究,对膳食种类、含量、膳食节律及其组合形成的膳食模式对于肠道微生物与机体健康的相关影响进行了论述,总结了肠道微生物与机体病理状态的相关研究,从状态相的角度解释膳食如何通过导向性饲喂影响肠道微生物组成结构,旨在能为进一步应用精准营养策略调控肠道微生物,保护机体健康与肠道平衡提供思路。