Effect of a low dose of dietary resveratrol on colon microbiota, inflammation and tissue damage in a DSS-induced colitis rat model

Ulcerative colitis: Gut microbiota, immunopathogenesis and application of natural products in animal models

Ulcerative colitis (UC) is an inflammatory bowel disease with increasing incidence in the world, especially in developing countries. Although knowledge of its pathogenesis has progressed over the last years, some details require clarification. Studies have highlighted the role of microbial dysbiosis and immune dysfunction as essential factors that may initiate the typical high-grade inflammatory outcome. In order to better understand the immunopathophysiological aspects of UC, experimental murine models are valuable tools. Some of the most commonly used chemicals to induce colitis are trinitrobenzene sulfonic acid, oxazolone and dextran sodium sulfate. These may also be used to investigate new ways of preventing or treating UC and therefore improving targeting in human studies. The use of functional foods or bioactive compounds from plants may constitute an innovative direction towards the future of alternative medicine. Considering the above, this review focused on updated information regarding the 1. gut microbiota and immunopathogenesis of UC; 2. the most utilized animal models of the disease and their relevance; and 3. experimental application of natural products, not yet tested in clinical trials.

Gastrointestinal Disorders and Metabolic Syndrome: Dysbiosis as a Key Link and Common Bioactive Dietary Components Useful for their Treatment

Gastrointestinal (GI) diseases, which include gastrointestinal reflux disease, gastric ulceration, inflammatory bowel disease, and other functional GI disorders, have become prevalent in a large part of the world population. Metabolic syndrome (MS) is cluster of disorders including obesity, hyperglycemia, hyperlipidemia, and hypertension, and is associated with high rate of morbidity and mortality. Gut dysbiosis is one of the contributing factors to the pathogenesis of both GI disorder and MS, and restoration of normal flora can provide a potential protective approach in both these conditions. Bioactive dietary components are known to play a significant role in the maintenance of health and wellness, as they have the potential to modify risk factors for a large number of serious disorders. Different classes of functional dietary components, such as dietary fibers, probiotics, prebiotics, polyunsaturated fatty acids, polyphenols, and spices, possess positive impacts on human health and can be useful as alternative treatments for GI disorders and metabolic dysregulation, as they can modify the risk factors associated with these pathologies. Their regular intake in sufficient amounts also aids in the restoration of normal intestinal flora, resulting in positive regulation of insulin signaling, metabolic pathways and immune responses, and reduction of low-grade chronic inflammation. This review is designed to focus on the health benefits of bioactive dietary components, with the aim of preventing the development or halting the progression of GI disorders and MS through an improvement of the most important risk factors including gut dysbiosis.

Biotransformation of dietary phytoestrogens by gut microbes: A review on bidirectional interaction between phytoestrogen metabolism and gut microbiota

Phytoestrogens are a class of plant produced polyphenolic compounds with diphenolic structure, which is similar to 17β-estradiol. These phytoestrogens preferentially bind to estrogen receptors, however, with weak affinity. Recently, many studies have found that these phytoestrogens can be transformed by gut microbiota through novel enzymatic reactions into metabolites with altered bioactivity. Recent studies have also implied that these metabolites could possibly modulate the host gut ecosystem, gene expression, metabolism and the immune system. Thus, isolating gut microbes capable of biotransforming phytoestrogens and characterizing the novel enzymatic reactions involved are principal to understand the mechanisms of beneficial effects brought by gut microbiota and their metabolism on phytoestrogens, and to provide the theoretical knowledge for the development of functional probiotics. In the present review, we summarized works on gut microbial biotransformation of phytoestrogens, including daidzin (isoflavone), phenylnaringenin (prenylflavonoid), lignans, resveratrol (stilbene) and ellagitannins. We mainly focus on gut bacterial isolation, metabolic pathway characterization, and the bidirectional interaction of phytoestrogens with gut microbes to illustrate the novel metabolic capability of gut microbiota and the methods used in these studies.

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.

Resveratrol rescues TNF‑α‑induced inhibition of osteogenesis in human periodontal ligament stem cells via the ERK1/2 pathway

Periodontitis is a common inflammatory disorder affecting the tissues surrounding the teeth, which can lead to the destruction of periodontal tissue and tooth loss. Resveratrol, a natural phytoalexin, exerts multiple biological effects. For example, its anti-inflammatory activity has been widely studied for the treatment of inflammatory bowel disease for a number of years. However, its effect on bone repair and new bone formation in an inflammatory microenvironment is not well understood. Accordingly, the effect of resveratrol on inflammation-affected human periodontal ligament stem cells (hPDLSCs) requires further investigation. In the present study, the effect of tumor necrosis factor-α (TNF-α), resveratrol, or the combination of both on the osteogenic differentiation of hPDLSCs, as well as the underlying mechanisms involved, were investigated. Cell Counting Kit-8 assay, alkaline phosphatase staining, Alizarin red staining, Oil Red O staining, reverse transcription-quantitative PCR and western blotting were used in the present study. It was demonstrated that resveratrol enhanced hPDLSC osteogenesis and reversed the inhibitory effects of TNF-α on this process. Further mechanistic studies indicated that resveratrol exerted anti-inflammatory activity by activating the ERK1/2 pathway, decreasing the secretion of interleukin (IL)-6 and IL-8 induced by TNF-α, and enhancing hPDLSCs osteogenesis. The present study suggested that resveratrol may be a novel and promising therapeutic choice for periodontitis.

Phytochemical drug candidates for the modulation of peroxisome proliferator-activated receptor γ in inflammatory bowel diseases

Plant-based compounds or phytochemicals such as alkaloids, glycosides, flavonoids, volatile oils, tannins, resins, and polyphenols have been used extensively in traditional medicine for centuries and more recently in Western alternative medicine. Extensive evidence suggests that consumption of dietary polyphenolic compounds lowers the risk of inflammatory diseases. The anti-inflammatory properties of several phytochemicals are mediated through ligand-inducible peroxisome proliferator-activated receptors (PPARs), particularly the PPARγ transcription factor. Inflammatory bowel disease (IBD) is represented by ulcerative colitis, which occurs in the mucosa of the colon and rectum, and Crohn's disease (CD) that can involve any segment of gastrointestinal tract. Because of the lack of cost-effective pharmaceutical treatment options, many IBD patients seek and use alternative and unconventional therapies to alleviate their symptoms. PPARγ plays a role in the inhibition of inflammatory cytokine expression and activation of anti-inflammatory immune cells. The phytochemicals reported here are ligands that activate PPARγ, which in turn modulates inflammatory responses. PPARγ is highly expressed in the gut making it a potential therapeutic target for IBDs. This review summarizes the effects of the currently published phytochemicals that modulate the PPARγ pathway and reduce or eliminate colonic inflammation.

Chemical composition of cold-pressed blackberry seed flour extract and its potential health-beneficial properties

The blackberry seed flour was cold-extracted using 50% acetone and examined for its phytochemical composition and health-beneficial properties including in vitro gut microbiota modulatory, free radical scavenging, anti-inflammatory, and antiproliferative capacities. Among identified thirteen components of blackberry seed flour extract through UHPLC-MS analysis, sanguiin H6 was the primary component and followed by ellagic acid and pedunculagin. For health-beneficial properties, the blackberry seed flour extract increased the total number of gut bacteria and shifted the abundance of specific bacterial phylum, family, or genus. The extract had RDSC, ORAC, HOSC, and ABTS•+ scavenging capacities of 362, 304, 2,531, and 267 μmol Trolox equivalents (TE)/g, respectively. In addition, the blackberry seed flour extract showed capacities for anti-inflammation and antiproliferation by suppressing LPS induced IL-1β mRNA expressions in the cultured J774A.1 mouse macrophages and the proliferation of LNCaP prostate cancer cells. The results suggest potential health benefits and further utilization of blackberry seed flour as functional foods.

Resveratrol attenuates intestinal injury in irradiated rats via PI3K/Akt/mTOR signaling pathway

Radiation-induced enteritis is one of the greatest challenges in radiotherapy. The current study was designed to evaluate the ameliorative effect of resveratrol, which exhibits anti-inflammatory property, against radiation-induced intestinal injury in rats and to explore the underlying mechanism. Rats were exposed to a single dose of 5 Gy. Resveratrol (20 mg/kg/day) was orally administered to irradiated rats over 3 weeks. Results showed that resveratrol ameliorated the intestinal oxidative stress parameters; malondialdehyde (MDA) content, glutathione (GSH) level, and catalase (CAT) activity compared to irradiated group. Furthermore, resveratrol reduced the contents of inflammatory cytokines; tumor necrosis factor α (TNF-α), nuclear factor-kappa (NF-κB), and interleukin 1β (IL-1β) in intestine. Western blotting analysis revealed that resveratrol down-regulated the proteins expression of phosphoinositide 3-kinases (PI3K), protein kinase B (Akt) as well as the mammalian target of rapamycin (mTOR) in intestinal tissues of irradiated rats and thus reduced the inflammatory mediator production. These results were confirmed by histopathological investigation. In conclusion, resveratrol attenuated intestinal inflammation following irradiation via modulating PI3K/Akt/mTOR pathway and thereby could be a promising adjuvant in radiotherapy.

Grape peel powder attenuates the inflammatory and oxidative response of experimental colitis in rats by modulating the NF-κB pathway and activity of antioxidant enzymes

Most phenolic compounds and dietary fiber reach intact to the colon. We hypothesized that grape peel powder (GPP), a rich source of these bioactive compounds, modulates inflammatory and oxidative pathways collaborating to attenuate colonic damage in experimental colitis. To determine which bioactive fraction would be responsible for this effect, the aim of this study was to evaluate the effect of dietary supplementation with whole GPP or the isolated bioactive-rich fractions from GPP (extractable polyphenols [EP], dietary fiber and fiber-bound polyphenols [NEP-F], and dietary fiber) in rats with experimental colitis. Colitis was induced by intrarectal injection of 2,4,6-trinitrobenzene sulfonic acid (TNBS) after 15 days of dietary supplementation. EP diet did not reverse the decrease in feed intake and indeed worsened colon shortening and increased spleen weight; however, these effects were not observed for the GPP group, which had polyphenols associated to the matrix besides the extractable ones. Colitis impaired the activity of colonic antioxidant enzymes and increased lipid peroxidation, protein oxidation, nitric oxide (NO) levels, and proinflammatory cytokines in serum and in the colon tissue. GPP restored the activity of antioxidant enzymes and decreased colon oxidation and NO levels. All grape peel fractions reduced the protein expression of the inhibitor of kappa kinase beta and NO levels in colon tissue, but only NEP-F reduced the expression of phosphorylated nuclear factor kappa B and myeloperoxidase activity. Results demonstrated that GPP attenuates inflammatory and oxidative response in TNBS-induced colitis by downregulating the nuclear factor kappa B pathway and upregulating antioxidant enzymes, with NEP-F being the fraction most likely associated to these protective effects.

Dietary resveratrol attenuated colitis and modulated gut microbiota in dextran sulfate sodium-treated mice

Accumulating evidence suggests that the gut microbiota plays an important role in the pathogenesis of colitis and that its composition could be modulated by exposure to dietary components. Thus, it may be possible to ameliorate the severity of colitis through administration of dietary components. Herein, we determined the effects of orally administered resveratrol on the gut microbiota composition and the resulting inflammatory status of a dextran sodium sulfate (DSS)-induced colitis mouse model. Our results supported our hypothesis that dietary resveratrol altered the microbial composition and restored microbial community diversity in DSS-treated mice. Specifically, resveratrol effectively decreased the abundance of the genera Akkermansia, Dorea, Sutterella and Bilophila, and increased the proportion of Bifidobacterium in colitic mice. Resveratrol was also able to prevent mouse body weight loss, reduce the disease activity index, attenuate tissue damage, and down-regulate the expression of pro-inflammatory cytokines such as IL-2, IFN-γ, GM-CSF, IL-1β, IL-6, KC/GRO, and TNF-α in the colon of DSS-treated mice. Pearson's correlation analysis indicated significant correlations between the relative levels of these pro-inflammatory cytokines and alterations of the gut microbiota. Our results demonstrated that dietary resveratrol attenuated the inflammatory status and alleviated gut microbiota dysbiosis in a colitis mouse model.

Recent Advances on the Anti-Inflammatory and Antioxidant Properties of Red Grape Polyphenols: In Vitro and In Vivo Studies

In this review, special emphasis will be placed on red grape polyphenols for their antioxidant and anti-inflammatory activities. Therefore, their capacity to inhibit major pathways responsible for activation of oxidative systems and expression and release of proinflammatory cytokines and chemokines will be discussed. Furthermore, regulation of immune cells by polyphenols will be illustrated with special reference to the activation of T regulatory cells which support a tolerogenic pathway at intestinal level. Additionally, the effects of red grape polyphenols will be analyzed in obesity, as a low-grade systemic inflammation. Also, possible modifications of inflammatory bowel disease biomarkers and clinical course have been studied upon polyphenol administration, either in animal models or in clinical trials. Moreover, the ability of polyphenols to cross the blood-brain barrier has been exploited to investigate their neuroprotective properties. In cancer, polyphenols seem to exert several beneficial effects, even if conflicting data are reported about their influence on T regulatory cells. Finally, the effects of polyphenols have been evaluated in experimental models of allergy and autoimmune diseases. Conclusively, red grape polyphenols are endowed with a great antioxidant and anti-inflammatory potential but some issues, such as polyphenol bioavailability, activity of metabolites, and interaction with microbiota, deserve deeper studies.

The Two-Way Polyphenols-Microbiota Interactions and Their Effects on Obesity and Related Metabolic Diseases

Metabolic diseases can change the gut microbiota composition and function, and pathogenic bacteria contribute to the development of metabolic disorders. Polyphenols may act in the gut microbiota to favor the increase of beneficial bacteria and hamper the increase of pathogenic bacteria. In addition, the microbiota may act on polyphenols to increase their bioavailability. This two-way interactions between polyphenols and the gut microbiota could affect human metabolism and reduce cardiometabolic risk. Despite the possible benefits of polyphenols for human health through modulating the microbiome, studies are scarce, and present several limitations. This review provides an overview of the polyphenol-microbiota interactions and its effects on metabolic disorders.

Synthetic Imine Resveratrol Analog 2-Methoxyl-3,6-Dihydroxyl-IRA Ameliorates Colitis by Activating Protective Nrf2 Pathway and Inhibiting NLRP3 Expression

Resveratrol (RSV) is a naturally occurring polyphenol that exhibits pleiotropic health benefits, including anticolitis and colon cancer-protective activity. Recently, we identified the novel imine RSV analog (IRA), 2-methoxyl-3,6-dihydroxyl-IRA 3,4,5,4-tetramethoxystilbene (C33), as a putative activator of nuclear factor erythroid 2-related factor 2 (Nrf2). The present study was designed to evaluate the ability of C33 to activate the Nrf2 signaling pathway and its anticolitis effect in comparison to RSV. The anticolitis action of C33 was assessed in a mouse model of colitis induced by dextran sulfate sodium (DSS). The effect of C33 on the Nrf2 signaling pathway was examined in vitro and in vivo. Compared to RSV, C33 triggered a more dramatic increase in the expression of genes downstream of Nrf2 in LS174T cells as well as in the small intestine and colon of wild-type (WT) mice. Correlated with its superior ability to activate the cytoprotective Nrf2 pathway, C33 was significantly better in ameliorating DSS-induced colitis by improving the inflammation score, as well as downregulating the markers of inflammation in WT mice. Moreover, induction of the NOD-like receptors family pyrin domain containing 3 (NLRP3) inflammasome by colitis was also significantly inhibited by the IRA. Nrf2 knockout completely abolished the effects of C33, indicating that Nrf2 is the important mechanistic target of C33 in vivo. In conclusion, the novel IRA, C33, has stronger anticolitis effects than RSV. Further studies are warranted to evaluate C33 as a potential therapeutic agent for inflammatory bowel disease and cancer chemoprevention.

Polyphenol Effects on Cholesterol Metabolism via Bile Acid Biosynthesis, CYP7A1: A Review

Atherosclerosis, the main contributor to coronary heart disease, is characterised by an accumulation of lipids such as cholesterol in the arterial wall. Reverse cholesterol transport (RCT) reduces cholesterol via its conversion into bile acids (BAs). During RCT in non-hepatic peripheral tissues, cholesterol is transferred to high-density lipoprotein (HDL) particles and returned to the liver for conversion into BAs predominantly via the rate-limiting enzyme, cholesterol 7 α-hydroxylase (CYP7A1). Numerous reports have described that polyphenol induced increases in BA excretion and corresponding reductions in total and LDL cholesterol in animal and in-vitro studies, but the process whereby this occurs has not been extensively reviewed. There are three main mechanisms by which BA excretion can be augmented: (1) increased expression of CYP7A1; (2) reduced expression of intestinal BA transporters; and (3) changes in the gut microbiota. Here we summarise the BA metabolic pathways focusing on CYP7A1, how its gene is regulated via transcription factors, diurnal rhythms, and microRNAs. Importantly, we will address the following questions: (1) Can polyphenols enhance BA secretion by modulating the CYP7A1 biosynthetic pathway? (2) Can polyphenols alter the BA pool via changes in the gut microbiota? (3) Which polyphenols are the most promising candidates for future research? We conclude that while in rodents some polyphenols induce CYP7A1 expression predominantly by the LXRα pathway, in human cells, this may occur through FXR, NF-KB, and ERK signalling. Additionally, gut microbiota is important for the de-conjugation and excretion of BAs. Puerarin, resveratrol, and quercetin are promising candidates for further research in this area.

Evaluation of the therapeutic activity of melatonin and resveratrol in Inflammatory Bowel Disease: A longitudinal PET/CT study in an animal model

Inflammatory Bowel Disease (IBD) is a group of chronic disorders of the gastrointestinal tract, which two main types are Crohn's disease and ulcerative colitis. Although conventional therapeutic strategies have demonstrated to be effective in the IBD treatment, it is necessary to incorporate novel therapeutic agents that target other mechanisms involved in the pathogenesis of the disease, such as oxidative stress. For this reason, the efficacy in vivo of two antioxidant compounds, melatonin and resveratrol, has been investigated in an animal model of TNBS (2, 4, 6-trinitrobenzenesulfonic acid) induced colitis. PET/CT (Positron emission tomography/Computer Tomography) scans were performed to assess disease activity and evaluate treatment response. SUV_max (Standardized Uptake Value) values, body weight changes and histological evaluation were used as inflammatory indices to measure the efficacy of both treatments. SUV_max values increased rapidly after induction of colitis, but after the beginning of the treatment (day 3) a statistically significant decrease was observed on days 7 and 10 in treated animals compared to the non-treated group. This remission of the disease was also confirmed by histological analysis of the colon tissue using the Nancy histological index (p value < 0.05 for differences between non-treated and both groups of treated animals). Moreover, statistical analysis showed a correlation (R² = 65.52%) between SUV_max values and weight changes throughout the treatment. Overall, this study demonstrates the potential of resveratrol, and melatonin in lower extent, as therapeutic agents in the IBD treatment.

Resveratrol Protects against Restraint Stress Effects on Stomach and Spleen in Adult Male Mice

The objectives were to investigate whether restraint stress (which is known as a mixture of psychologic and physical stress) exerts negative effects on the stomach and spleen, and whether the phenolic compound resveratrol (RES) exerts any protective roles. Fifty adult male mice were divided into five groups, with 10 mice per group as follows: control (C), restraint stress (RS), RS with vehicle (RS + V), RS with 2 mg/kg of resveratrol (RS + 2 mg RES), and RS with 20 mg/kg of resveratrol (RS + 20 mg RES). Mice were restrained in conical centrifuge tubes for 4 h daily to establish the RS model. RS + 2 mg RES, RS + 20 mg RES, and RS + V groups were given an oral dose of resveratrol or vehicle for 15 consecutive days, while the control group was not exposed to restraint stress. Herein, we showed that restraint stress decreased body weight and food and water consumption in stressed groups RS and RS + V compared to controls, while the groups treated with resveratrol showed improvements. Moreover, restraint stress caused acute damage to the morphology of gastric cells and reduced the quantitative distribution of parietal cells along with their decreased size and diameter, pointing to gastritis or ulcer. Furthermore, the antibody against the apoptosis-inducing factor (AIF) was highly attached in the RS groups. Splenic size, weight, and length were also greatly augmented in the stressed groups compared to the controls, while these phenomena were not observed in the RS + 2 mg RES group. Our findings proved significant ameliorating effects of resveratrol against restraint stress in adult male mice.

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

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.

Beneficial Effects of Dietary Polyphenols on Gut Microbiota and Strategies to Improve Delivery Efficiency

The human intestine contains an intricate ecological community of dwelling bacteria, referred as gut microbiota (GM), which plays a pivotal role in host homeostasis. Multiple factors could interfere with this delicate balance, including genetics, age, antibiotics, as well as environmental factors, particularly diet, thus causing a disruption of microbiota equilibrium (dysbiosis). Growing evidences support the involvement of GM dysbiosis in gastrointestinal (GI) and extra-intestinal cardiometabolic diseases, namely obesity and diabetes. This review firstly overviews the role of GM in health and disease, then critically reviews the evidences regarding the influence of dietary polyphenols in GM based on preclinical and clinical data, ending with strategies under development to improve efficiency of delivery. Although the precise mechanisms deserve further clarification, preclinical and clinical data suggest that dietary polyphenols present prebiotic properties and exert antimicrobial activities against pathogenic GM, having benefits in distinct disorders. Specifically, dietary polyphenols have been shown ability to modulate GM composition and function, interfering with bacterial quorum sensing, membrane permeability, as well as sensitizing bacteria to xenobiotics. In addition, can impact on gut metabolism and immunity and exert anti-inflammatory properties. In order to overcome the low bioavailability, several different approaches have been developed, aiming to improve solubility and transport of dietary polyphenols throughout the GI tract and deliver in the targeted intestinal regions. Although more research is still needed, particularly translational and clinical studies, the biotechnological progresses achieved during the last years open up good perspectives to, in a near future, be able to improve the use of dietary polyphenols modulating GM in a broad range of disorders characterized by a dysbiotic phenotype.

Effects of resveratrol on intestinal oxidative status and inflammation in heat-stressed rats

Heat stress, experienced by humans and animals under high ambient temperatures, is known to induce oxidative stress and inflammation, which endangers human health as well as animal welfare and production. The gastrointestinal tract is predominantly responsive to heat stress and compromised intestinal functions can contribute to multi-organ injury under heat environment. Resveratrol (RSV) has significant antioxidant and anti-inflammatory activities. The aim of this study was to investigate the potential effects of RSV on intestinal function (digestion and barrier), oxidative stress and inflammation in heat-stressed rats. Male Sprague-Dawley rats were orally fed with 100 mg RSV/kg body weight/day prior to daily heat stress (40 °C per day for 1.5 h) exposure for 3 consecutive days. The results showed that RSV reversed the increased serum cortisol level and diamine oxidase activity, the altered jejunal morphology, the decreased jejunal disaccharidase activities, the elevated malondialdehyde and tumor necrosis factor alpha concentrations and antioxidant enzymes activities in the jejunum, as well as the increased jejunal mRNA expression of toll-like receptor 4, cytokines, antioxidant enzymes and tight junction proteins in heat-stressed rats, to various degrees. In conclusion, RSV could alleviate intestinal injury and dysfunctions by improving oxidative status and suppressing inflammation in heat-stressed rats.

Polyphenols in the management of brain disorders: Modulation of the microbiota-gut-brain axis

The modulation of the microbiota-gut-brain axis with a view to preventing and treating brain disorders became recently a hot topic for the scientific community. Dietary polyphenols are multifaceted compounds that have demonstrated to be highly advantageous to counteract inflammation, oxidative stress, and neurodegeneration, among other pathological conditions, being useful in the prevention and treatment of several chronic disorders. The potential of these compounds to prevent and treat brain disorders has not been only related to their capacity to reach the brain, depending on their chemical structure, and interact directly with brain cells, but also to their ability to modulate the communication between the brain and the gut, interfering with multiple branches of this axis. Preclinical studies have demonstrated the potential of these food bioactive compounds in brain diseases, namely, neurodevelopmental, such as Down's syndrome and Autism spectrum disorder, neurodegenerative, such as Parkinson's disease and Alzheimer's disease, and psychiatric disorders, such as depression and anxiety. Until now, dietary polyphenols have been recognized as promising nutraceuticals to combat brain disorders. However, the impact of these compounds on the gut-brain interconnection remains poorly elucidated. Also, clinical assays are crucial to further support the beneficial effects of these compounds as demonstrated in preclinical research.

Resveratrol-mediated glycemic regulation is blunted by curcumin and is associated to modulation of gut microbiota

The polyphenols resveratrol (RSV) and curcumin (Cur) are phytoalexines and natural antibiotics with numerous pharmacological functions and metabolic impacts. Recent evidences show a broad control of gut microbiota by polyphenols which could influence glycemic regulation. The aim of this work is to estimate the respective effect of RSV and Cur alone or in association on the control of glycemia and on gut microbiota. A 5-week chronic treatment of hyperglycemic mice with RSV and/or Cur resulted in a differential effect on glucose tolerance test and modified gut microbiome. We precisely identified groups of bacteria representing a specific signature of the glycemic effect of RSV. Inferred metagenomic analysis and metabolic pathway prediction showed that the sulfur and branched-chain amino-acid (BCAA) metabolic activities are tightly correlated with the efficacy of RSV for the control of glycaemia. The impact on BCAA metabolism was further validated by serum metabolomics analysis. Altogether, we show that polyphenols specifically impact gut microbiota and corresponding metabolic functions which could be responsible for their therapeutic role.

Dietary Supplementation with Sea Bass (Lateolabrax maculatus) Ameliorates Ulcerative Colitis and Inflammation in Macrophages through Inhibiting Toll-Like Receptor 4-Linked Pathways

Sea bass (Lateolabrax maculatus) is a kind of food material commonly consumed in daily life. In traditional Chinese medicinal books, it has been indicated that sea bass can be applied for managing many inflammation-associated conditions. However, the studies on the pharmacological mechanisms of inflammation of sea bass remain scarce. Hence, this study aims to investigate the molecular mechanisms of the anti-inflammatory activity of sea bass. Anti-inflammatory activities of sea bass were assessed using dextran sulfate sodium (DSS)-induced colitis in a mice model and lipopolysaccharide (LPS)-activated macrophages model. Low body weight and short colon length were observed in DSS-fed mice that were significantly recovered upon sea bass treatments. Moreover, the colon histopathology score showed that sea bass-treated mice had decreased crypt damage, focal inflammation infiltration and the extent of inflammation, suggesting that treatment with sea bass could attenuate intestinal inflammation. In addition, the in-vitro study conjointly indicated that sea bass could suppress the inflammatory mediators in LPS-activated macrophage by inhibiting the TLR4-linked pathway. The present findings demonstrated that sea bass has an inhibitory effect on TLR4 signaling; thus, it could be a promising candidate for treating inflammation-associated conditions. A further justification for the clinical application of sea bass in treating inflammation-associated conditions is necessary.

Intestinal Immunomodulation and Shifts on the Gut Microbiota of BALB/c Mice Promoted by Two Bifidobacterium and Lactobacillus Strains Isolated from Human Samples

Bifidobacterium animalis subsp. lactis IPLA 20020 and Lactobacillus gasseri IPLA 20212, two strains isolated from human samples, were evaluated for safety and influence over the intestinal microbiota and cytokine production by the intestinal tissue of adult BALB/c mice. Mice were divided into four groups receiving during 8 days PBS or a suspension of each strain, prepared fresh or lyophilized (bifidobacteria), at an amount of 4x10⁸ viable cells/day. This dose could be comparable to the probiotic intake of a human adult who consumed about 100-200 mL of functional fermented milk per day, considering the usual level of probiotics in commercial products. No microbial translocation to liver or alterations in food intake, weight, and behavior were observed in treated mice. Intestinal content of secretory immunoglobulin A (s-IgA) was not affected, discarding any adverse effect on the mucosa-associated immunity. The profile of intestinal proinflammatory/regulatory cytokines after intervention evidenced that the microbial strain administered and its cellular state (fresh or lyophilized) as well as the host tissue analyzed (small or large intestine) influenced the immune response and suggests a moderate shift towards a T helper 1 profile (Th1) in the large intestine after the administration of both strains. Changes on relative levels of some intestinal microbial groups were evidenced after intervention. It is noteworthy that butyrate was positively associated with a balanced pro-Th1 immune response. Therefore, B. animalis subsp. lactis IPLA20020 and L. gasseri IPLA 20212 could be considered potential probiotic candidates to be included in functional foods for balancing the intestinal immune response.

Flaxseed Lignans as Important Dietary Polyphenols for Cancer Prevention and Treatment: Chemistry, Pharmacokinetics, and Molecular Targets

Cancer causes considerable morbidity and mortality across the world. Socioeconomic, environmental, and lifestyle factors contribute to the increasing cancer prevalence, bespeaking a need for effective prevention and treatment strategies. Phytochemicals like plant polyphenols are generally considered to have anticancer, anti-inflammatory, antiviral, antimicrobial, and immunomodulatory effects, which explain their promotion for human health. The past several decades have contributed to a growing evidence base in the literature that demonstrate ability of polyphenols to modulate multiple targets of carcinogenesis linking models of cancer characteristics (i.e., hallmarks and nutraceutical-based targeting of cancer) via direct or indirect interaction or modulation of cellular and molecular targets. This evidence is particularly relevant for the lignans, an ubiquitous, important class of dietary polyphenols present in high levels in food sources such as flaxseed. Literature evidence on lignans suggests potential benefit in cancer prevention and treatment. This review summarizes the relevant chemical and pharmacokinetic properties of dietary polyphenols and specifically focuses on the biological targets of flaxseed lignans. The consolidation of the considerable body of data on the diverse targets of the lignans will aid continued research into their potential for use in combination with other cancer chemotherapies, utilizing flaxseed lignan-enriched natural products.

Grape peel powder promotes intestinal barrier homeostasis in acute TNBS-colitis: A major role for dietary fiber and fiber-bound polyphenols

Inflammatory bowel diseases are characterized by impaired intestinal barrier function. This study aimed to evaluate the effects of grape peel powder (GPP) and its bioactive rich-fractions on the barrier function and colonic injury in a model of colitis induced by 2,4,6 trinitrobenzene sulfonic acid (TNBS). Wistar rats received diets supplemented with either GPP (8%), extractable polyphenols (EP), non-extractable polyphenols-rich fraction (NEP-F), or polyphenols-poor, fiber-rich fraction (F) from grapes at amounts equivalent to the GPP group during 15 days before and for 7 days after colitis induction. NEP-F has decreased the extension of colonic lesion but the other grape peel bioactive fractions did not protect against macroscopic or microscopic colonic damage, EP diet increased macroscopic colonic damage. GPP, EP, and NEP-F reduced claudin-2 mRNA expression, whereas GPP and F fraction increased occludin and ZO-1 mRNA expression. All experimental diets reduced the colitis-triggered increase of MMP-9 mRNA expression. Colitis reduced by 30% the production of cecal short-chain fatty acids (SCFA). GPP and NEP-F completely protected against this effect, whereas F fraction was ineffective. Only GPP and NEP-F were able to decrease the upregulation of GRP94 mRNA triggered by colitis. Dietary fiber seems to reestablish the intestinal barrier function, whereas fiber-bound phenolics were able to restore cecal metabolism to produce beneficial metabolites like SCFA and to reduce the activation of the unfolded protein response.

The Bidirectional Interactions between Resveratrol and Gut Microbiota: An Insight into Oxidative Stress and Inflammatory Bowel Disease Therapy

Dysbiosis and oxidative stress in the gut have contributed to the progression of intestinal inflammatory bowel disease (IBD). The current study has reported that enteric bacteria mediate redox homeostasis through the regulation of reactive oxygen species (ROS) production. Resveratrol, one of the most abundant polyphenols, with poor oral bioavailability, is considered as a scavenger of ROS and other free radicals. Recent studies have shown that resveratrol effectively enhances the growth of Lactococcus lactis and inhibits the growth of Enterococcus faecalis. (1) In terms of the two-way relationship between gut microbiota and resveratrol, resveratrol modulates gut microbiota; (2) in terms of resveratrol biotransformation by gut microbiota, we speculate that gut microbiota could be a target of resveratrol to maintain gut homeostasis. Here, we reviewed the current researches about the cellular signaling pathways in intestinal epithelial cells triggered by gut microbiota in response to oxidative stress. These results suggest that the modulation of the gut microbiota through resveratrol supplementation appears as a promising potential approach for the therapy of inflammatory bowel disease.

The gut microbiota composition affects dietary polyphenols-mediated cognitive resilience in mice by modulating the bioavailability of phenolic acids

Dietary polyphenols promote memory in models of sleep deprivation (SD), stress, and neurodegeneration. The biological properties of dietary polyphenols greatly depend upon the bioavailability of their phenolic metabolites derivatives, which are modulated by gut microbiota. We recently demonstrated that supplementation with grape-derived bioactive dietary polyphenol preparation (BDPP) improves SD-induced cognitive impairment. This study examined the role of the gut microbiota in the ability of BDPP to prevent memory impairment in response to SD. C57BL6/J mice, treated with antibiotics mix (ABX) or BDPP or both, were sleep-deprived at the end of a fear conditioning training session and fear memory was assessed the next day. Gut microbiota composition was analyzed in fecal samples and BDPP-driven phenolic acid metabolites extraction was measured in plasma. We report that the beneficial effect of BDPP on memory in SD is attenuated by ABX-induced dysbiosis. We identified specific communities of fecal microbiota that are associated with the bioavailability of BDPP-derived phenolic acids, which in turn, are associated with memory promotion. These results suggest the gut microbiota composition significantly affects the bioavailability of phenolic acids that drive the dietary polyphenols' cognitive resilience property. Our findings provide a preclinical model with which to test the causal association of gut microbiota-polyphenols, with the ultimate goal of potential developing dietary polyphenols for the prevention/treatment of cognitive impairment.

Effect of Selected Stilbenoids on Human Fecal Microbiota

Dietary phenolics or polyphenols are mostly metabolized by the human gut microbiota. These metabolites appear to confer the beneficial health effects attributed to phenolics. Microbial composition affects the type of metabolites produced. Reciprocally, phenolics modulate microbial composition. Understanding this relationship could be used to positively impact health by phenolic supplementation and thus create favorable colonic conditions. This study explored the effect of six stilbenoids (batatasin III, oxyresveratrol, piceatannol, pinostilbene, resveratrol, thunalbene) on the gut microbiota composition. Stilbenoids were anaerobically fermented with fecal bacteria from four donors, samples were collected at 0 and 24 h, and effects on the microbiota were assessed by 16S rRNA gene sequencing. Statistical tests identified affected microbes at three taxonomic levels. Observed microbial composition modulation by stilbenoids included a decrease in the Firmicutes to Bacteroidetes ratio, a decrease in the relative abundance of strains from the genus Clostridium, and effects on the family Lachnospiraceae. A frequently observed effect was a further decrease of the relative abundance when compared to the control. An opposite effect to the control was observed for Faecalibacterium prausnitzii, whose relative abundance increased. Observed effects were more frequently attributed to resveratrol and piceatannol, followed by thunalbene and batatasin III.

Role of Intestinal Microbiota in the Bioavailability and Physiological Functions of Dietary Polyphenols

Polyphenols are categorized as plant secondary metabolites, and they have attracted much attention in relation to human health and the prevention of chronic diseases. In recent years, a considerable number of studies have been published concerning their physiological function in the digestive tract, such as their prebiotic properties and their modification of intestinal microbiota. It has also been suggested that several hydrolyzed and/or fission products, derived from the catabolism of polyphenols by intestinal bacteria, exert their physiological functions in target sites after transportation into the body. Thus, this review article focuses on the role of intestinal microbiota in the bioavailability and physiological function of dietary polyphenols. Monomeric polyphenols, such as flavonoids and oligomeric polyphenols, such as proanthocyanidins, are usually catabolized to chain fission products by intestinal bacteria in the colon. Gallic acid and ellagic acid derived from the hydrolysis of gallotannin, and ellagitannin are also subjected to intestinal catabolism. These catabolites may play a large role in the physiological functions of dietary polyphenols. They may also affect the microbiome, resulting in health promotion by the activation of short chain fatty acids (SCFA) excretion and intestinal immune function. The intestinal microbiota is a key factor in mediating the physiological functions of dietary polyphenols.

Resveratrol and Its Human Metabolites-Effects on Metabolic Health and Obesity

Resveratrol is one of the most widely studied polyphenols and it has been assigned a plethora of metabolic effects with potential health benefits. Given its low bioavailability and extensive metabolism, clinical studies using resveratrol have not always replicated in vitro observations. In this review, we discuss human metabolism and biotransformation of resveratrol, and reported molecular mechanisms of action, within the context of metabolic health and obesity. Resveratrol has been described as mimicking caloric restriction, leading to improved exercise performance and insulin sensitivity (increasing energy expenditure), as well as having a body fat-lowering effect by inhibiting adipogenesis, and increasing lipid mobilization in adipose tissue. These multi-organ effects place resveratrol as an anti-obesity bioactive of potential therapeutic use.

Regulation of Adaptive Thermogenesis and Browning by Prebiotics and Postbiotics

Prebiotics are non-digestible food components able to modify host microbiota toward a healthy profile, concomitantly conferring general beneficial health effects. Numerous research works have provided wide evidence regarding the effects of prebiotics on the protection against different detrimental phenotypes related to cancer, immunity, and features of the metabolic syndrome, among others. Nonetheless, one topic less studied so far, but relevant, relates to the connection between prebiotics and energy metabolism regulation (and the prevention or treatment of obesity), especially by means of their impact on adaptive (non-shivering) thermogenesis in brown adipose tissue (BAT) and in the browning of white adipose tissue (WAT). In the present review, a key link between prebiotics and the regulation of adaptive thermogenesis and lipid metabolism (in both BAT and WAT) is proposed, thus connecting prebiotic consumption, microbiota selection (especially gut microbiota), production of microbiota metabolites, and the regulation of energy metabolism in adipose tissue, particularly regarding the effects on browning promotion, or on BAT recruitment. In this sense, various types of prebiotics, from complex carbohydrates to phenolic compounds, have been studied regarding their microbiota-modulating role and their effects on crucial tissues for energy metabolism, including adipose tissue. Other studies have analyzed the effects of the main metabolites produced by selected microbiota on the improvement of metabolism, such as short chain fatty acids and secondary bile acids. Here, we focus on state-of-the-art evidence to demonstrate that different prebiotics can have an impact on energy metabolism and the prevention or treatment of obesity (and its associated disorders) by inducing or regulating adaptive thermogenic capacity in WAT and/or BAT, through modulation of microbiota and their derived metabolites.

Maternal dietary resveratrol alleviates weaning-associated diarrhea and intestinal inflammation in pig offspring by changing intestinal gene expression and microbiota

Maternal dietary resveratrol alters intestinal gene expression and microbiota in offspring.

Effect of caseinate glycation with oligochitosan and transglutaminase on the intestinal barrier function of the tryptic caseinate digest in IEC-6 cells

The oligochitosan-glycated caseinate digest has higher activity than the caseinate digest to strengthen the intestinal barrier function of IEC-6 cells.

Interaction between gut microbiota and ethnomedicine constituents

This highlight reviews the interaction processes between gut microbiota and ethnomedicine constituents, which may conceptualize future therapeutic strategies.

Influence of the Maillard-type caseinate glycation with lactose on the intestinal barrier activity of the caseinate digest in IEC-6 cells

The glycated caseinate digest of the Maillard-type shows lower capability than the caseinate digest to enhance the intestinal barrier function of IEC-6 cells.

Causal Relationship between Diet-Induced Gut Microbiota Changes and Diabetes: A Novel Strategy to Transplant Faecalibacterium prausnitzii in Preventing Diabetes

The incidence of metabolic disorders, including diabetes, has elevated exponentially during the last decades and enhanced the risk of a variety of complications, such as diabetes and cardiovascular diseases. In the present review, we have highlighted the new insights on the complex relationships between diet-induced modulation of gut microbiota and metabolic disorders, including diabetes. Literature from various library databases and electronic searches (ScienceDirect, PubMed, and Google Scholar) were randomly collected. There exists a complex relationship between diet and gut microbiota, which alters the energy balance, health impacts, and autoimmunity, further causes inflammation and metabolic dysfunction, including diabetes. Faecalibacterium prausnitzii is a butyrate-producing bacterium, which plays a vital role in diabetes. Transplantation of F. prausnitzii has been used as an intervention strategy to treat dysbiosis of the gut’s microbial community that is linked to the inflammation, which precedes autoimmune disease and diabetes. The review focuses on literature that highlights the benefits of the microbiota especially, the abundant of F. prausnitzii in protecting the gut microbiota pattern and its therapeutic potential against inflammation and diabetes.

Aqueous extract of berry (Plinia jaboticaba) byproduct modulates gut microbiota and maintains the balance on antioxidant defense system in rats

Previous studies have assessed the properties of aqueous extracts, using byproducts such as jaboticaba peel. We have assessed potential antioxidant effects of jaboticaba extract (Plinia jaboticaba) (JAE = 50 g/L) in vitro and in vivo. Healthy Wistar rats received ad libitum JAE for either 15 or 49 days in vivo. Cyanidin-3-O-glucoside, delphinidin-3-O-glucoside, gallic acid, rutin, myricetin, and quercetin were identified as the main polyphenols in JAE. Lipid peroxidation values in the serum and colon were similar throughout the groups. In addition, JAE did not disturb the antioxidant systems. JAE also altered gut microbiota, increasing since Lactobacillus, Bifidobacterium and Enterobacteriaceae counts. Bacterial metabolites were higher in the colon content of rats fed with JAE than in the control group. Given these results, under healthy conditions, JAE dietary supplementation could perform in vivo modulation of gut microbiota, without disturbing the antioxidant system. PRACTICAL APPLICATION: Jaboticaba (Plinia jaboticaba) peel is a rich and often-wasted source of bioactive compounds, such as polyphenols. Previous studies have shown that physiological benefits of this berry. The jaboticaba peel could contribute to antioxidant defense systems; it may also have an effect over gut microbiota related to polyphenols contents. Aqueous extraction may be a practical way of employing the bioactive compounds of jaboticaba peel; these compounds can be consumed daily and safely, and thus have attracted particular attention. This work showed positive impacts of jaboticaba peel treatments on microbiota and antioxidant defense systems, and could guide future clinical studies.

Prebiotic-Like Effects of Water Soluble Chitosan on the Intestinal Microflora in Mice

In the present work, water soluble chitosan (WSC) was prepared and growth curves of Lactobacillus delbrueckii and Escherichia coli were examined in vitro. In vivo, mice were randomly divided into three groups (10 mice in each group), treated with water, 1 g/kg WSC and 0.25 g/kg of WSC respectively for 24 days. Subsequently, levofloxacin (65 mg/kg) was given for 6 days. The dynamic changes of bacterial communities were evaluated by denaturing gradient gel electrophoresis periodically. L. delbrueckii and E. coli have been inhibited by WSC in vitro. The bacteria from the genera of Bacteroides, Lactobacillus, Enterococcus and Devosia were dominant gut flora in the intestinal tract of mice. The growth of Lactobacillus has been dramatically stimulated, whereas Enterococcus faecium and Parabacteroides distasonis which were opportunistic bacterial pathogens have been inhibited. So WSC can be considered as a new food supplement to protect the intestinal microflora and regulate imbalance.

Immunomodulatory Properties of Adipose-Derived Stem Cells Treated with 5-Azacytydine and Resveratrol on Peripheral Blood Mononuclear Cells and Macrophages in Metabolic Syndrome Animals

Endocrine disorders, including equine metabolic syndrome (EMS), are a serious issue in veterinary medicine and horse breeding. Furthermore, EMS was shown to affect the cytophysiological properties of adipose-derived stem cells, reducing their therapeutic potential. However, it was shown that those cells can be rejuvenated while using a combination of two chemicals: 5-azacytydine (AZA) and resveratrol (RES). In the present study, we decided to evaluate the immunomodulatory properties of AZA/RES-treated adipose-derived stem cells (ASC) isolated from EMS horses (ASCEMS). Thus, we co-cultured ASC with peripheral blood mononuclear cells (PBMC) and RAW264.7 macrophages. Most attention was placed on regulatory T lymphocytes (TREG), as well as the messenger RNA (mRNA) and protein levels of several cytokines (tumor necrosis factor α (TNF-α), interleukin (IL)-6, IL-10, and IL-1β). Moreover, we also investigated the expression of genes related to auto- and mitophagy in both PBMCs and ASCs. PBMCs were obtained from healthy and EMS-suffering individuals and were co-cultured with ASCs that were isolated from healthy and EMS horses cultured in control conditions and with AZA/RES. We discovered that cells treated with AZA/RES increase the TREG number while co-cultured with PBMCs. Moreover, the co-culture of PBMCs with AZA/RES-treated ASCEMS induced mitophagy in PBMCs. Furthermore, ASCEMS pre-treated with AZA/RES displayed anti-inflammatory properties, as decreased levels of TNF-α, nitric oxide (NO), and IL-6 were observed in those cells in comparison with their untreated counterparts in the co-culture with RAW264.7 macrophages. In summary, we demonstrated that ASCEMS treated with AZA/RES displayed increased anti-inflammatory properties, and was able to regulate and activate the TREG-related anti-inflammatory response.

Connection between Systemic Inflammation and Neuroinflammation Underlies Neuroprotective Mechanism of Several Phytochemicals in Neurodegenerative Diseases

Oxidative damage, mitochondrial dysfunction, and neuroinflammation are strongly implicated in the pathogenesis of neurodegenerative diseases including Alzheimer's disease (AD) and Parkinson's disease (PD), and a substantial portion of elderly population at risk of these diseases requires nutritional intervention to benefit health due to lack of clinically relevant drugs. To this end, anti-inflammatory mechanisms of several phytochemicals such as curcumin, resveratrol, propolis, polyunsaturated fatty acids (PUFAs), and ginsenosides have been extensively studied. However, correlation of the phytochemicals with neuroinflammation or brain nutrition is not fully considered, especially in their therapeutic mechanism for neuronal damage or dysfunction. In this article, we review the advance in antioxidative and anti-inflammatory effects of phytochemicals and discuss the potential communication with brain microenvironment by improved gastrointestinal function, enhanced systemic immunity, and neuroprotective outcomes. These data show that phytochemicals may modulate and suppress neuroinflammation of the brain by several approaches: (1) reducing systemic inflammation and infiltration via the blood-brain barrier (BBB), (2) direct permeation into the brain parenchyma leading to neuroprotection, (3) enhancing integrity of disrupted BBB, and (4) vagal reflex-mediated nutrition and protection by gastrointestinal function signaling to the brain. Therefore, many phytochemicals have multiple potential neuroprotective approaches contributing to therapeutic benefit for pathogenesis of neurodegenerative diseases, and development of strategies for preventing these diseases represents a considerable public health concern and socioeconomic burden.

The impact of exercise training and resveratrol supplementation on gut microbiota composition in high-fat diet fed mice

The aim of this study was to examine the effect of exercise training and dietary supplementation of resveratrol on the composition of gut microbiota and to test the hypothesis that exercise training and resveratrol can prevent high-fat diet (HFD)-induced changes in the gut microbiota. Mice fed a HFD supplemented with resveratrol (4 g/kg food) were protected against diet-induced obesity, while exercise trained HFD-fed animals (running on average 50 km/week) were not. Dietary resveratrol supplementation induced changes predominantly in the low-abundant bacteria, while exercise training induced changes in the high-abundant bacteria in the gut as analyzed by ADONIS test with Weighted UniFrac distances. Interestingly, the two interventions affected the gut microbiome independently of the inflammatory state of the HFD-fed animals as assessed by the systemic serum amyloid A levels. These results suggest that both resveratrol supplementation and regular physical activity modulate the composition of murine microbiota independently of the systemic inflammatory state. Moreover, the effects of exercise training on the microbiota seem to occur without changes in adiposity, while resveratrol-mediated alterations may relate to adipose tissue mass.

A role for plant science in underpinning the objective of global nutritional security?

Background

The challenges of achieving global food security have become more demanding as scientists have realized that not only calorie content but also food composition and colonic microbial content impact our health and well-being, dramatically. The ways that the nutrients we consume affect our health are highly complex due to the diversity of what we eat, the varying digestibility of what we eat, the changing composition and functioning of each individual's gut microbiota, the differences in absorption and bioavailability of the nutrients we eat, the differences in responses between individuals to what they eat and the multi-fold mechanisms of action that nutrients have on our health.

Perspective and Conclusions

It has been accepted for more than 50 years that diets rich in plants, particularly fruit and vegetables, protect health, and yet such diets have declined, with lower fruit and vegetable content and much more cheap, sugary, oily, processed foods, over the same period. These dietary shifts have had a marked impact on the incidence of chronic diseases: obesity, metabolic diseases, type 2 diabetes and cardiovascular diseases. Greater support for research into the ways that plant-based foods impact health will be essential for changing dietary patterns to protect health and to achieve global nutritional security.

Targeted Approaches for In Situ Gut Microbiome Manipulation

Microbial communities and their collective genomes form the gut microbiome, of which bacteria are the major contributor. Through their secreted metabolites, bacteria interact with the host, influencing human health and physiology. Perturbation of the microbiota and metabolome has been associated with various diseases and metabolic conditions. As knowledge on fundamental host-microbiome interactions and genetic engineering tools becomes readily available, targeted manipulation of the gut microbiome for therapeutic applications gains favourable attention. Manipulation of the gut microbiome can be achieved by altering the microbiota population and composition, or by modifying the functional metabolic activity of the microbiome to promote health and restore the microbiome balance. In this article, we review current works that demonstrate various strategies employed to manipulate the gut microbiome in situ to various degrees of precision.