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.     

Bidirectional interactions between dietary curcumin and gut microbiota

Abstract

Curcumin is a polyphenolic compound with a long history of use as an herbal remedy, dietary spice, and food-coloring agent. Despite curcumin possesses a wide range of biological and pharmacological activities, it exhibits extremely poor bioavailability, which makes its pharmacology intriguing and also hinders its clinical application. In recent years, there is ample evidence supporting the associations between the alteration of gut microbiota and many diseases. Interestingly, after oral administration, curcumin shows its preferential distribution and accumulation in the intestine. In view of the above aspects, we reviewed the updated knowledge regarding the bidirectional interactions between curcumin and gut microbiota from two perspectives: (1) gut microbiota regulation by curcumin and (2) curcumin biotransformation by digestive microbiota. Besides the study deals with 3 potential pharmacological implications: (1) identification of metabolites being more active and bioavaliable than parent curcumin; (2) assessment of contribution of gut microbiota regulation of curcumin to its pharmacological effects and (3) development of gut microbiota regulation-based disease prevention/treatment strategy for curcumin in view of its clinical safety. This review is important to deepen our understanding of the mechanisms of action of curcumin and to provide future directions about how to use this natural compound to combat human diseases.     

Dietary compounds and traditional Chinese medicine ameliorate type 2 diabetes by modulating gut microbiota

Abstract

Diabetes mellitus (DM) and its complications are major public health concerns which strongly influence the quality of humans’ life. Modification of gut microbiota has been widely used for the management of diabetes. In this review, the relationship between diabetes and gut microbiota, as well as the effects of different dietary components and traditional Chinese medicine (TCM) on gut microflora are summarized. Dietary compounds and TCM possessing bioactive components (fiber and phytochemicals) first change the composition of gut microbiota (inhibiting pathogens and promoting the beneficial bacteria growth) and then influence the production of their metabolites, which would further modify the intestinal environment through inhibiting the production of detrimental compounds (such as lipopolysaccharide, hydrogen sulfide, indol, etc.). Importantly, metabolites (short chain fatty acids and other bioactive components) fermented/degraded by gut microbiota can target multiple pathways in intestine, liver, pancreas, etc., resulting in the improvement of gut health, glycemic control, lipids profile, insulin resistance and inflammation. Furthermore, understanding the interaction between different dietary components and gut microbiota, as well as underlying mechanisms would help design different diet formula for the management of diabetes. Further researches could focus on the combination of different dietary components for preventing and treating diabetes, based on the principle of “multiple components against multiple targets” from the perspective of gut microbiota.     

Reciprocal interactions between resveratrol and gut microbiota deepen our understanding of molecular mechanisms underlying its health benefits

BackgroundResveratrol is a stilbene-based phytochemical, which possesses multiple pharmacological activities. However, the low bioavalibility of resveratrol mystifies its pharmacology.Scope and approachWe discussed the reciprocal interactions of resveratrol with gut microbiota as investigated by in vitro, animal models as well as humans studies.Key findings and conclusionsThe first part described the current in vitro and in vivo evidence concerning the modulative effect of resveratrol on gut microbiota composition, particularly focusing on the involvement of gut microbiota modulation in the anti-diabetic, anti-obesity, and anti-atherosclerosis effects of resveratrol. The second part summarized the bioconversion of resveratrol by gut microbiota, and the identification of metabolites along with bacterial species as generators of these metabolites. This may not only help reconcile the bioavailability conundrum of resveratrol, but also provide directions to expedite its medical applications.     

Dietary polysaccharide from Mung bean [Vigna radiate (Linn.) Wilczek] skin modulates gut microbiota and short-chain fatty acids in mice

Cumulative evidence revealed that the gut microbiota play important role in human health. Polysaccharide from Mung bean [Vigna radiate (Linn.) Wilczek] skin has been confirmed to have a variety of biological activities, but its effect on the gut microbiota has not been considered. This study aimed to investigate the effect of hot water extraction of mung bean skin water-soluble polysaccharides (MBP-2) on the gut microbiota of Balb/c mice and its main metabolite short-chain fatty acids (SCFAs). The results showed that supplementation with MBP-2 increased the colon length and the production of SCFAs in Balb/c mice, and improved the intestinal microenvironment by producing SCFAs, which is beneficial to the intestinal health of mice. MBP-2 increased the Chao1 index and ACE index in a dose-depended manner, and changed the structure of the gut microbiota and significantly promoted the growth of probiotic bacteria in Balb/c mice. The faecal bacterial flora of mice is mainly composed of nine phyla and twenty-seven genera, MBP-2 can regulate the composition of intestinal flora by increasing Firmicutes, Bacteroidetes, Clostridium and decreasing TM7, thereby maintaining intestinal health.     

Consumption of Fish in Chronic Kidney Disease – A Matter of Depth

Fish is an excellent source of ω-3 polyunsaturated fatty acids (PUFAs), amino acids, collagen, vitamins, and iodine and its intake is associated with health benefits, mainly reduces risk of cardiovascular mortality. However, recent studies have shown that fish is also an important source of trimethylamine N-oxide (TMAO), a uremic toxin produced by the gut microbiota that promotes an increased risk of cardiovascular diseases. In patients with chronic kidney disease (CKD), TMAO levels are markedly increased due to gut dysbiosis and reduced kidney function. No study has yet evaluated the effects of a fish-rich diet on TMAO plasma levels and cardiovascular outcomes. This review discusses the pros and cons of a fish-rich diet in patients with CKD – a matter of depth.     

枸杞多糖体外调节人体肠道菌群的功能研究

为研究枸杞多糖(LBP)对人体肠道菌群结构和代谢产物的影响,对6名健康人的粪便提取物进行单独样本与混合样本的体外模拟厌氧发酵,利用16S rRNA基因高通量测序技术对发酵后肠道菌群进行结构和功能分析,并利用超高效液相色谱(UPLC)检测发酵液中的短链脂肪酸(SCFAs)浓度。结果表明,LBP能够明显改变人体肠道菌群结构与功能,提高肠道菌群中益生菌乳酸杆菌属与双歧杆菌属的丰度,并促进了SCFAs的产生。因此,LBP能够显著影响人体肠道菌群结构与功能。     

Dietary fat and gut microbiota: mechanisms involved in obesity control

ABSTRACT

Obesity is a serious global health problem that is directly related to various morbidities manifestation. Intestinal dysbiosis has been implicated on obesity pathogenesis. Diet composition can alter gut microbiota, regardless of energy intake. Dietary fatty acids quality may affect gut microbiota composition, which in turn may affect host metabolic health. The mechanisms by which the different type of FFA modulate gut microbiota is yet poor elucidate and there is a lack of studies regard to this. Fatty acids may act in cell membrane, interfere with energy production, inhibit enzymatic activities, impair nutrient absorption and generate toxic compounds to cells, leading to growth inhibition or even bacterial death. The beneficial effect of the consumption of n-3 polyunsaturated fatty acids (PUFA) and conjugated linoleic acid (CLA) on microbiota, unlike n-6 PUFA and saturated fatty acids has been suggested. n-3 PUFA consumption promotes desirable changes on obese intestinal microbiota making it similar to that of normal weight individuals. More studies are needed to better understand the effect of CLA on microbiota and host health. Long term human controlled clinical trials must be conducted to allow us to understand the complex interaction between dietary fat, intestinal microbiota and obesity.     

The Gut Microbiota and Its Metabolites,Novel Targets for Treating and Preventing Non‐Alcoholic Fatty Liver Disease

Non‐alcoholic fatty liver disease (NAFLD) is one of the most prevalent metabolic disorders worldwide, along with obesity and type 2 diabetes. NAFLD involves a series of liver abnormalities from simple hepatic steatosis to non‐alcoholic steatohepatitis, which can ultimately lead to liver cirrhosis and cancer. The gut–liver axis plays an important role in the development of NAFLD, which depends mainly on regulation of the gut microbiota and its bacterial products. These intestinal bacterial species and their metabolites, including bile acids, tryptophan catabolites, and branched‐chain amino acids, regulate adipose tissue and intestinal homeostasis and contribute to the pathogenesis of NAFLD/non‐alcoholic steatohepatitis. In this review, the current evidence regarding the key role of the gut microbiota and its metabolites in the pathogenesis and development of NAFLD is highlighted, and the advances in the progression and applied prospects of gut microbiota‐targeted dietary and exercise therapies is also discussed.     

A critical review of the relationship between dietary components,the gut microbe Akkermansia muciniphila,and human health

Abstract

The human gut contains trillions of microorganisms with a great diversity that are associated with various health benefits. Recent studies have reported an increasing correlation between diet, gut microbiota, and human health, indicating rapid development in the field of gut health. Diet is an important factor that determines the gut microbiota composition. The gut comprises great diversities of microbes involved in immune modulation and other functions. In particular, Akkermansia muciniphila is a mucin-degrading bacterium is believed to have several health benefits in humans. Several studies have evaluated the prebiotic effects of various dietary components on A. muciniphila and their association with various ailments, such as diabetes mellitus, atherosclerosis, and cancer. Hence, this review aims to provide a plausible mechanistic basis for the interactions between dietary components, and A. muciniphila and for the therapeutic benefits of this interaction on various illnesses.     

Modulation of the human gut microbiota by phenolics and phenolic fiber‐rich foods

The gut microbiota plays a prominent role in human health. Alterations in the gut microbiota are linked to the development of chronic diseases such as obesity, inflammatory bowel disease, metabolic syndrome, and certain cancers. We know that diet plays an important role to initiate, shape, and modulate the gut microbiota. Long‐term dietary patterns are shown to be closely related with the gut microbiota enterotypes, specifically long‐term consumption of carbohydrates (related to Prevotella abundance) or a diet rich in protein and animal fats (correlated to Bacteroides). Short‐term consumption of solely animal‐ or plant‐based diets have rapid and reproducible modulatory effects on the human gut microbiota. These alterations in microbiota profile by dietary alterations can be due to impact of different dietary macronutrients, carbohydrates, protein, and fat, which have diverse modulatory effects on gut microbial composition. Food‐derived phenolics, which encompass structural variants of flavonoids, hydroxybenzoic acids, hydroxycinnamic acids, coumarins, stilbenes, ellagitannins, and lignans can modify the gut microbiota. Gut microbes have been shown to act on dietary fibers and phenolics to produce functional metabolites that contribute to gut health. Here, we discuss recent studies on the impacts of phenolics and phenolic fiber‐rich foods on the human gut microbiota and provide an insight into potential synergistic roles between their bacterial metabolic products in the regulation of the intestinal microbiota.     

Current and future experimental approaches in the study of grape and wine polyphenols interacting gut microbiota

Interactions between polyphenols and gut microbiota are indeed a major issue of current interest in food science research. Knowledge in this subject is progressing as the experimental procedures and analysis techniques do. The aim of this article is to critically review the more leading-edge approaches that have been applied so far in the study of the interactions between grape/wine polyphenols and gut microbiota. This is the case of in vitro dynamic gastrointestinal simulation models that try to mitigate the limitations of simple static models (batch culture fermentations). More complex approaches include the experimentation with animals (mice, rats, pigs, lambs and chicks) and nutritional intervention studies in humans. Main advantages and limitations as well as the most relevant findings achieved by each approach in the study of how grape/wine polyphenols can modulate the composition and/or functionality of gut microbiota, are detailed. Also, common findings obtained by the three approaches (in vitro, animal models and human nutritional interventions) such as the fact that the Firmicutes/Bacteroidetes ratio tends to decrease after the feed/intake/consumption of grape/wine polyphenols are highlighted. Additionally, a nematode (Caenorhabditis elegans) model, previously used for investigating the mechanisms of processes such as aging, neurodegeneration, oxidative stress and inflammation, is presented as an emerging approach for the study of polyphenols interacting gut microbiota. © 2020 Society of Chemical Industry     

Is gut microbiota a relevant and competitive dietary target for cardio-metabolic health? Proceedings of an expert workshop

BackgroundThe gut microbiota is a putative target for dietary interventions for cardio-metabolic health (CMH), including prevention of obesity, type 2 diabetes, and cardiovascular disease. This has generated considerable interest, but the actual feasibility for diet or specific foods to induce measurable, sustained and meaningful benefits for CMH risk by this route remains uncertain.Scope and approachThis report summarises an expert workshop assessing the gut microbiota as a relevant, feasible and competitive target for CMH benefits by dietary interventions. It summarises the expert presentations and overall view of participants on the current status and outlook, considering also implications for the food industry.Key findings and conclusionsChanging the gut microbiota by diet is possible, but an assessment of the impact on CMH risk is still needed, including clarifying advantages above other known dietary routes. The individual gut microbiota composition may in part determine the impact of diet and its effects on health. Therefore, future developments may identify individuals at risk and thus possible modification of the microbiota to achieve benefits in susceptible (sub) populations depending on their initial microbiota composition. Prebiotics currently appear to be the most promising ingredients; however, required doses may be relatively high and the actual role of gut microbiota needs further assessment. Overall, causal evidence linking gut microbiota interventions with CMH benefits are developing in preclinical models but are still lacking in humans. A significant research effort is needed and ongoing to determine whether potential effects can be reliably substantiated.     

Human health-promoting interactions between hydrocolloid-structured foods and the gut microbiome in the digestive tract: Editorial

There is a growing interest to overcome such diet-related health issues through the interactions with gut microbiome. A complex network of interactions between nutrition, gut microbiota and health has gradually emerged, which has been rarely explored in its whole. Imbalance of the normal gut microbiota has been linked with gastrointestinal conditions. This editorial highlighted the recent developments in the hydrocolloid-structured foods and the gut microbiome in the digestive tract.     

Rethinking the Mechanism of the Health Benefits of Proanthocyanidins: Absorption,Metabolism, and Interaction with Gut Microbiota

Proanthocyanidins, as the oligomers or polymers of flavan‐3‐ol, are widely discovered in plants such as fruits, vegetables, cereals, nuts, and leaves, presenting a major part of dietary polyphenols. Although proanthocyanidins exert several types of bioactivities, such as antioxidant, antimicrobial, cardioprotective, and neuroprotective activity, their exact mechanisms remain unclear. Due to the complexity of the structure of proanthocyanidins, such as their various monomers, different linkages and isomers, investigation of their bioavailability and metabolism is limited, which further hinders the explanation of their bioactivities. Since the large molecular weight and degree of polymerization limit the bioavailability of proanthocyanidins, the major effective site of proanthocyanidins is proposed to be in the gut. Many studies have revealed the effects of proanthocyanidins from different sources on changing the composition of gut microbiota based on in vitro and in vivo models and the bioactivities of their metabolites. However, the metabolic routes of proanthocyanidins by gut microbiota and their mutual interactions are still sparse. Thus, this review summarizes the chemistry, absorption, and metabolic pathways of proanthocyanidins ranging from monomers to polymers, as well as the mutual interactions between proanthocyanidins and gut microbiota, in order to better understand how proanthocyanidins exert their health‐promoting functions.     

Interplay between gut microbiota,its metabolites and human metabolism: Dissecting cause from consequence

BackgroundAlterations in gut microbiota composition and bacterial metabolites have been increasingly recognized to affect host metabolism and are at the basis of metabolic diseases such as obesity and type 2 diabetes (DM2). Intestinal enteroendocrine cells (EEC's) sense gut luminal content and accordingly secrete hormones that modulate glucose and lipid metabolism and affect satiety. It has become evident that microbial metabolic products significantly affect EEC function.Scope and approachIn this review, we will discuss current insights in the role of the gut microbiota and its metabolites in development of obesity and DM2 and elaborate on interventions that modulate EEC action.Key findings and conclusionsStudies including fecal transplantation and Roux-en-Y gastric bypass (RYGB) in humans and animal models suggest that the gut microbiota and its metabolites causally contribute to development of obesity and DM2. Emerging evidence suggests that the gut microbiota and its metabolites can modulate secretion of EEC hormones that regulate appetite and insulin secretion. Dispersed intestinal expression and low abundance make EEC's difficult to study. Since current intestinal sampling methods in humans are mostly limited to the colon, this leaves a large part of EEC function understudied. It would therefore be relevant to develop means to extend sampling methods throughout to entire GI tract.     

Hydroxycinnamic acids and human health: recent advances

There is an urgent need to improve human diet globally. Compelling evidence gathered over the past several decades suggests that a suboptimal diet is associated with many chronic diseases and may be responsible for more deaths than any other risks worldwide. The main components in our diet that need higher intake are whole grains, fruit and vegetables, and nuts and seeds; all of these are important sources of dietary fiber and polyphenols. The health benefits of dietary fiber and polyphenols are also supported by several decades of valuable research. However, the conclusions drawn from interventional human trials are not straightforward and the action mechanisms in improving human health are not fully understood. Moreover, there is a great inter-individual variation caused by different individual capabilities of processing, absorbing and using these compounds effectively. Data on the bioavailability and bioefficacy of hydroxycinnamic acids (HCAs) are limited when compared to other classes of polyphenols (e.g. anthocyanins). This review aims to summarize the latest research advances related to HCA bioavailability and their biological effects revealed by epidemiological data, pre-clinical and clinical studies. Moreover, we aim to review the effects of HCAs on gut microbiota diversity and function and its respective influence on host health. © 2019 Society of Chemical Industry     

高脂膳食与肠道微生态相关性研究进展

近年来,随着人们的生活习惯向高脂膳食转变,高脂膳食诱发的食源性肥胖、心血管疾病、糖尿病等相关 慢性代谢疾病已经成为困扰全球的公共卫生问题。越来越多的研究表明,肠道微生态和高脂膳食诱发的代谢紊乱关 系密切。受膳食、遗传背景和生活方式等因素的影响,肠道微生态的组成存在着很大的个体差异。膳食不仅仅为宿 主提供营养物质,也是肠道微生物营养的来源,能影响肠道微生态的组成和功能。宿主的能量代谢、肠道通透性的 保持以及一些炎症反应和免疫反应均与肠道微生态的改变相关。本文综述了高脂膳食、肠道微生态和宿主健康之间 的相互影响及其可能的作用机理。虽然目前的研究结果还无法证实肠道微生态与高脂膳食诱发的相关慢性代谢疾病 是否存在因果关系,但肠道微生态与宿主健康之间的相互影响为肥胖及其相关代谢疾病的防治提供了新思路。     

肠源性短链脂肪酸生成机制及其饮食调控

短链脂肪酸(short chain fatty acids, SCFAs)作为肠道微生物的重要代谢产物,将宿主饮食与肠道微生物之间复杂的相互作用关系有机地联系在一起。SCFAs是近年来微生物代谢产物与人体健康科研领域研究热点,SCFAs不仅作为肠道上皮细胞的重要能源物质,也是游离脂肪酸受体的天然配体,因此发挥着多种健康作用,如调节脂质代谢、免疫、炎症反应和食欲等。阐述了肠源性SCFAs前体物质的主要食物来源,详细探讨了参与SCFAs生成的肠道微生物及代谢途径,并提出了肠源性SCFAs的饮食调控策略。从化学结构上看,SCFAs是一类碳原子数小于7的挥发性有机酸,肠源性SCFAs主要包括乙酸、丙酸、丁酸,它们主要是由SCFAs前体物质在肠道菌群的酵解作用下转化生成。SCFAs前体物质的食物来源多种多样,不易消化的碳水化合物是SCFAs的主要食物前体,包含抗性淀粉、非淀粉多糖、低聚糖等。肠道中的多种微生物能够通过不同代谢途径独立或者协同利用SCFAs前体物质产生SCFAs。补充富含SCFAs前体物质的食物,不仅能够影响肠源性SCFAs的含量,还可选择性地促进肠道中有益菌的生长,从质和量上维护肠道微生态稳态、直接或者间接地调节机体多种生理功能,促进人体健康功能。希望可为预防和治疗相关代谢和免疫疾病提供新的思路。