褐藻膳食纤维对机体代谢及其肠道菌群调节作用的研究进展

褐藻膳食纤维（海藻酸盐,Alg）是存在于海洋食用藻类中的一种酸性多糖,具有多种生物活性作用。研究表明,褐藻膳食纤维可有效地改善肠道菌群的组成结构,通过菌群代谢膳食纤维发酵产物调节宿主机体的代谢水平,从而改善肥胖、糖尿病等代谢相关性疾病。从作为食品添加剂的角度出发,对褐藻膳食纤维作用于人和动物模型体重、血糖、脂代谢以及肠道菌群的效果加以综述,并探讨其潜在机制,为海洋功能性产品的开发和应用提供科学依据。     

膳食纤维对肥胖相关的肠道微生态的影响

研究发现,肠道微生态的改变与肥胖等代谢性疾病相关。膳食纤维作为饮食的一部分,通过在肠道的作用改变肠道菌群比例及丰度、改善炎症反应、调节肠道激素及脂质代谢来改善肥胖,但膳食纤维在防治肥胖方面的推荐摄入量、种类及与肠道菌群的作用机制还需进一步研究。本文对膳食纤维对肥胖相关的肠道微生态的影响的研究进展进行了综述。     

基于肠道微生态探讨黄连素在代谢性疾病中的抗炎作用

肠道菌群与能量代谢密切相关,其组成和代谢紊乱可通过多种途径导致胰岛素抵抗,肥胖和2型糖尿病。黄连素因具有减重、降糖、调脂等作用被广泛用于肥胖、2型糖尿病及非酒精性脂肪性肝病等代谢性疾病的辅助治疗;研究表明,黄连素可调节肠道菌群的组成和代谢,改善肠道微生态环境,从而改善胰岛素抵抗和代谢。本文综述了黄连素通过肠道菌群-炎症轴在干预代谢性疾病的研究进展,以期为代谢性疾病的治疗寻找新的策略,并为今后该领域的深入研究提供指导意义。     

肠道菌群与高血压病主要危险因素的相关性及中药干预研究现状

近年来国内、外文献报道高血压病的发生可能与肠道菌群失调相关。肠道菌群与高血压病主要危险因素（肥胖、高血脂、糖尿病、代谢综合征、动脉粥样硬化）具有一定的相关性,某些益生菌或其发酵产品可能通过改善肠道菌群的方式为高血压病的治疗提供新的思路和途径。近年来研究显示中药具有较长的肠道停留时间,从而有利于其发挥调节肠道菌群的作用,提示某些中药具有调节肠道菌群的作用。但目前国内、外尚无关于中药直接通过肠道菌群作用而干预高血压病的文献报道,而近年来国内有研究显示肠道菌群可能是中药干预高血压病主要危险因素的作用机制之一。     

常见几种功能性低聚糖对肠道菌群调节机制的研究进展

低聚糖(oligosaccharides)又称寡糖,是一种新型功能性糖源。它可分为普通低聚糖和功能性低聚糖,目前研究较多的是功能性低聚糖。功能性低聚糖对肠道菌群的调节机制已成为医学研究的热点之一。目前研究比较成熟的功能性低聚糖主要有低聚果糖、低聚木糖、大豆低聚糖、低聚异麦芽糖和低聚半乳糖等。同时,由于香蕉的润肠通便作用,对香蕉低聚糖的研究日益成为热点。现就常见的几种功能性低聚糖对肠道菌群调节机制的研究进展作一综述。     

Faecalibacterium prausnitzii与人类疾病关系的研究进展

Faecalibacterium prausnitzii（F. prausnitzii）是定植于哺乳动物胃肠道中的共生菌,同时也是健康成人肠道菌群中最丰富的细菌之一。本研究主要对F. prausnitzii与人体代谢性疾病如肥胖、糖尿病及宿主的消化道疾病如炎症性疾病、结肠癌等疾病的相关研究现状进行综述,着重讨论了F. prausnitzii作为潜在益生菌在肠道疾病中的重要作用,进而通过使用益生菌或者改变肠道内F. prausnitzii的数量达到预防或治疗肥胖、糖尿病及肠道疾病的目的。     

肥胖相关的肠道微生物群落结构动力学与功能解析研究

肥胖及相关的慢性代谢性疾病近年来已经成为威胁全球的公共健康问题。越来越多的证据表明,在宿主的营养、免疫和代谢中有不可替代的作用的肠道菌群不仅可以通过调节宿主脂肪吸收存储相关的基因,影响后者的能量平衡,更重要的是其结构失调导致宿主循环系统中内毒素增加,诱发慢性、低水平炎症,导致肥胖和胰岛素抵抗。运用微生物分子生态学、元基因组学和代谢组学的方法,揭示与代谢性疾病相关的菌群结构失调,并鉴定出相关的特定细菌类群及其功能,使得通过以菌群为靶点的营养干预手段防止慢性代谢性疾病成为可能,将带来代谢性疾病预防和控制策略的革命性的变化。     

2型糖尿病肠道菌群研究进展

2型糖尿病是一种常见的慢性消耗性疾病,其发病机制十分复杂,流行病学研究表明,肥胖、高热量饮食、体力活动不足及年龄增大是2型糖尿病最主要的环境因素。它是一种以胰岛素抵抗和胰岛素分泌不足为特征的代谢性疾病。肠道菌群作为进入人体的一个重要环境因素,肠道微生物的菌群变化影响宿主能量物质的吸收,调节肠道的分泌功能和非特异性免疫功能,从营养、代谢、疾病等各方面与我们生命活动相关。肠道菌群已成为我们身体的一部分,影响宿主的免疫,在肥胖、糖尿病、代谢综合征等疾病中都具有非常重要的作用。     

肠道菌群在代谢手术改善肥胖代谢性疾病中的研究进展

肥胖不仅是体内脂肪细胞的增加,而且是机体代谢状态的异常改变,导致肥胖患者出现2型糖尿病、非酒精性脂肪性肝病、心血管疾病和多囊卵巢综合征等代谢紊乱性疾病。代谢手术在减重的同时,能够治疗和缓解由肥胖导致的相关疾病。对代谢手术改善肥胖及其合并症的机制研究发现,肠道微生物在术后显著改变,这促使肠道菌群及其代谢产物（短链脂肪酸和胆汁酸）等成为代谢手术改善代谢效应机制研究的热点。随着粪菌移植和口服益生菌治疗肥胖及其合并症的报道,进一步验证了肠道菌群在改善肥胖及其相关并发症中发挥有益作用。本综述将总结肠道菌群在代谢手术领域中的最新研究进展。     

肠道菌群对2型糖尿病的调节机制

2型糖尿病(type 2 diabetes mellitus,T2DM)是一种遗传和环境因素共同作用的复杂的代谢性疾病,约占糖尿病患者总数的90％以上。以往,人们一直认为导致T2DM发生的肥胖是外部因素所致,但目前已有证据表明,身体内部因素同样是导致肥胖的诱因之一。人体微生物群的最新研究表明,个体肠道中的特定菌群可能促进肥胖、炎症或胰岛素抵抗的发生,最终诱发T2DM。这使得肠道菌群及其在T2DM中的作用以及肠道益生菌的潜在治疗价值成为T2DM领域中的一个重要研究方向。本综述旨在通过研究健康人群和T2DM患者肠道菌群的分布,探讨肠道菌群与T2DM的相互作用及调节机制。     

肠道菌群在肥胖发病中的作用

近十年来,肠道菌群在人类许多疾病发病机制中的潜在作用引起了人们的广泛关注。已被证实肠道菌群与肥胖和肥胖相关的代谢性疾病的发生发展密切相关。与肥胖相关的肠道微生物可调控宿主的能量代谢、胰岛素抵抗和脂肪组织堆积,这些在肥胖发生中都起着至关重要的作用。本综述重点介绍了代谢紊乱中肠道菌群组成的变化以及肠道菌群在肥胖发病机制中的作用,包括能量代谢、中枢食欲、免疫系统和宿主昼夜节律。在不久的将来,该领域的研究将为治疗肥胖及其并发症开辟新的途径。     

Obesity and the gut microbiota: does up-regulating colonic fermentation protect against obesity and metabolic disease?

Obesity is now considered a major public health concern globally as it predisposes to a number of chronic human diseases. Most developed countries have experienced a dramatic and significant rise in obesity since the 1980s, with obesity apparently accompanying, hand in hand, the adoption of "Western"-style diets and low-energy expenditure lifestyles around the world. Recent studies report an aberrant gut microbiota in obese subjects and that gut microbial metabolic activities, especially carbohydrate fermentation and bile acid metabolism, can impact on a number of mammalian physiological functions linked to obesity. The aim of this review is to present the evidence for a characteristic "obese-type" gut microbiota and to discuss studies linking microbial metabolic activities with mammalian regulation of lipid and glucose metabolism, thermogenesis, satiety, and chronic systemic inflammation. We focus in particular on short-chain fatty acids (SCFA) produced upon fiber fermentation in the colon. Although SCFA are reported to be elevated in the feces of obese individuals, they are also, in contradiction, identified as key metabolic regulators of the physiological checks and controls mammals rely upon to regulate energy metabolism. Most studies suggest that the gut microbiota differs in composition between lean and obese individuals and that diet, especially the high-fat low-fiber Western-style diet, dramatically impacts on the gut microbiota. There is currently no consensus as to whether the gut microbiota plays a causative role in obesity or is modulated in response to the obese state itself or the diet in obesity. Further studies, especially on the regulatory role of SCFA in human energy homeostasis, are needed to clarify the physiological consequences of an "obese-style" microbiota and any putative dietary modulation of associated disease risk.     

Amino acid supplements and metabolic health: a potential interplay between intestinal microbiota and systems control

Dietary supplementation of essential amino acids (EAAs) has been shown to promote healthspan. EAAs regulate, in fact, glucose and lipid metabolism and energy balance, increase mitochondrial biogenesis, and maintain immune homeostasis. Basic science and epidemiological results indicate that dietary macronutrient composition affects healthspan through multiple and integrated mechanisms, and their effects are closely related to the metabolic status to which they act. In particular, EAA supplementation can trigger different and even opposite effects depending on the catabolic and anabolic states of the organisms. Among others, gut-associated microbial communities (referred to as gut microbiota) emerged as a major regulator of the host metabolism. Diet and host health influence gut microbiota, and composition of gut microbiota, in turn, controls many aspects of host health, including nutrient metabolism, resistance to infection, and immune signals. Altered communication between the innate immune system and the gut microbiota might contribute to complex diseases. Furthermore, gut microbiota and its impact to host health change largely during different life phases such as lactation, weaning, and aging. Here we will review the accumulating body of knowledge on the impact of dietary EAA supplementation on the host metabolic health and healthspan from a holistic perspective. Moreover, we will focus on the current efforts to establish causal relationships among dietary EAAs, gut microbiota, and health during human development.     

肠道菌群与代谢综合征研究进展

代谢综合征是导致心脑血管疾病的危险因素之一,被认为是威胁全球人类健康的公共卫生问题。肠道菌群紊乱与肥胖、2型糖尿病及非酒精性脂肪性肝病等代谢性疾病的相关性已被普遍接受,因此肠道菌群调控有望成为治疗代谢综合征的新靶点。本文对肠道菌群与代谢综合征的关系、肠道菌群影响代谢综合征的可能机制以及与肠道菌群相关的调控策略作一综述。

     

Metabolomics characterization of energy metabolism reveals glycogen accumulation in gut-microbiota-lacking mice

Microbiota in the gut are considered an important environmental factor associated with host metabolism and physiology. Although gut microbiota are known to contribute to hepatic lipogenesis and fat storage, little is known about how the condition influences the deposition of glycogen in the liver. To better understand and characterize the host energy metabolism in guts lacking microbiota, we compared the liver metabolome of specific pathogen-free and germ-free mice by gas chromatography-mass spectrometry combined with partial least-squares discriminant analysis. We identified 30 of 52 highly reproducible peaks in chromatograms of liver tissue extracts from the two groups of mice. The two groups showed significant differences in metabolic profile. Changes in liver metabolism involved metabolites such as amino acids, fatty acids, organic acids and carbohydrates. The metabolic profile of germ-free mice suggests that they synthesize glycogen and accumulate it in the liver through gluconeogenesis and glycogenesis. Our findings shed light on a new perspective of the role of gut microbiota in energy metabolism and will be useful to help study probiotics, obesity and metabolic diseases.     

Anti-obesity effects of gut microbiota are associated with lactic acid bacteria

The prevalence of obesity is rapidly becoming endemic in industrialized countries and continues to increase in developing countries worldwide. Obesity predisposes people to an increased risk of developing metabolic syndrome. Recent studies have described an association between obesity and certain gut microbiota, suggesting that gut microbiota might play a critical role in the development of obesity. Although probiotics have many beneficial health effects in humans and animals, attention has only recently been drawn to manipulating the gut microbiota, such as lactic acid bacteria (LAB), to influence the development of obesity. In this review, we first describe the causes of obesity, including the genetic and environmental factors. We then describe the relationship between the gut microbiota and obesity, and the mechanisms by which the gut microbiota influence energy metabolism and inflammation in obesity. Lastly, we focus on the potential role of LAB in mediating the effects of the gut microbiota in the development of obesity.     

益生菌以及益生元在肥胖及其代谢综合征中的潜在作用

肥胖以及相关的代谢综合征已经成为全球性的公共健康问题。大量的研究表明,肥胖形成以及减肥过程均与肠道菌群密切相关且相互影响。肠道菌群以及弱炎症反应成为肥胖以及相关代谢综合征的两大重要影响因素。本文综述了近几年来,肠道菌群失调对宿主能量储存以及新陈代谢的影响,以及弱炎症反应对肥胖引起的代谢综合征的影响。大量的研究证明,益生元有助于益生菌的生长,而益生菌可以调节肠道菌群以及改善肠道内弱炎症反应,借助于益生菌以及益生元的方法也许能为由肠道菌群失调以及弱炎症反应引起的肥胖及其代谢综合征提供一种新的治疗方法。     

Focus: Microbiome: Treating Obesity and Metabolic Syndrome with Fecal Microbiota Transplantation

The worldwide prevalence of metabolic syndrome, which includes obesity and its associated diseases, is rising rapidly. The human gut microbiome is recognized as an independent environmental modulator of host metabolic health and disease. Research in animal models has demonstrated that the gut microbiome has the functional capacity to induce or relieve metabolic syndrome. One way to modify the human gut microbiome is by transplanting fecal matter, which contains an abundance of live microorganisms, from a healthy individual to a diseased one in the hopes of alleviating illness. Here we review recent evidence suggesting efficacy of fecal microbiota transplant (FMT) in animal models and humans for the treatment of obesity and its associated metabolic disorders.