Gut Microbiota Dysbiosis in Obesity-Linked Metabolic Diseases and Prebiotic Potential of Polyphenol-Rich Extracts

Exploring Therapeutic Advances: A Comprehensive Review of Intestinal Microbiota Modulators

The gut microbiota establishes a mutually beneficial relationship with the host starting from birth, impacting diverse metabolic and immunological processes. Dysbiosis, characterized by an imbalance of microorganisms, is linked to numerous medical conditions, including gastrointestinal disorders, cardiovascular diseases, and autoimmune disorders. This imbalance promotes the proliferation of toxin-producing bacteria, disrupts the host's equilibrium, and initiates inflammation. Genetic factors, dietary choices, and drug use can modify the gut microbiota. However, there is optimism. Several therapeutic approaches, such as probiotics, prebiotics, synbiotics, postbiotics, microbe-derived products, and microbial substrates, aim to alter the microbiome. This review thoroughly explores the therapeutic potential of these microbiota modulators, analysing recent studies to evaluate their efficacy and limitations. It underscores the promise of microbiota-based therapies for treating dysbiosis-related conditions. This article aims to ensure practitioners feel well-informed and up to date on the most influential methods in this evolving field by providing a comprehensive review of current research.

Untargeted metabolomics analysis of probiotic jujube juice and its anti-obesity effects on high-fat-diet-induced obese mice

BACKGROUND

Dietary intervention, including polyphenol consumption, is recognized as an effective strategy to prevent obesity. Although fermented jujube juice (FJJ) with lactic acid bacteria has been shown to be rich in polyphenols and have strong antioxidant properties, little is known about its anti-obesity properties.

RESULTS

Untargeted metabolomics was employed to identify and analyze the differential metabolites between FJJ and raw jujube juice. A total of 431 metabolites belonging to diverse classes and with various functional active ingredients were quantitatively identified. The animal experiments results showed that FJJ administration for 13 weeks significantly inhibited high-fat-diet-induced body and epididymal adipose weight gain, and improved the serum lipid parameters in obese mice. Additionally, DNA-sequencing results revealed that FJJ treatment increased Akkermansia abundance in the gut and changed the composition of fecal microbiota by decreasing the Firmicutes/Bacteroidota ratio and Helicobacter pylori abundance.

CONCLUSION

These findings suggest that FJJ contributes to regulating lipid accumulation and gut microbiota composition in high-fat-diet-induced obese mice, which helps to prevent obesity. Hence, FJJ has the potential to be a beneficial beverage for controlling obesity. © 2024 Society of Chemical Industry.

Diet composition drives tissue-specific intensity of murine enteric infections

Diet composition plays a large role in regulating gut health and enteric infection. In particular, synthetic "Western-style" diets may predispose to disease, while whole-grain diets containing high levels of crude fiber are thought to promote gut health. Here, we show that, in contrast to this paradigm, mice fed with unrefined chow are significantly more susceptible to infection with Trichuris muris, a caecum-dwelling nematode, than mice fed with refined, semi-synthetic diets (SSDs). Moreover, mice fed with SSD supplemented with inulin, a fermentable fiber, developed chronic T. muris burdens, whereas mice fed with SSD efficiently cleared the infection. Diet composition significantly impacted infection-induced changes in the host gut microbiome. Mice infected with the bacterium Citrobacter rodentium were also more susceptible to pathogen colonization when fed with either chow or inulin-enriched SSD. However, transcriptomic analysis of tissues from mice fed with either SSD or inulin-enriched SSD revealed that, in contrast to T. muris, increased C. rodentium infection appeared to be independent of the host immune response. Accordingly, exogenous treatment with interleukin (IL)-25 reduced T. muris burdens in inulin-fed mice, whereas IL-22 treatment was unable to restore resistance to C. rodentium colonization. Diet-mediated effects on pathogen burden were more pronounced for large intestine-dwelling pathogens, as effects on small the intestinal helminth (Heligmosomoides polygyrus) were less evident, and protozoan (Giardia muris) infection burdens were equivalent in mice fed with chow, inulin-enriched SSD, or SSD, despite higher cyst excretion in chow-fed mice. Collectively, our results point to a tissue- and pathogen-restricted effect of dietary fiber levels on enteric infection intensity.IMPORTANCEEnteric infections induce dysbiosis and inflammation and are a major public health burden. As the gut environment is strongly shaped by diet, the role of different dietary components in promoting resistance to infection is of interest. While diets rich in fiber or whole grain are normally associated with improved gut health, we show here that these components predispose the host to higher levels of pathogen infection. Thus, our results have significance for interpreting how different dietary interventions may impact on gastrointestinal infections. Moreover, our results may shed light on our understanding of how gut flora and mucosal immune function is influenced by the food that we eat.

Exploring global research status and trends in anti-obesity effects of traditional Chinese medicine through intestinal microbiota: a bibliometric study

Background

The intestinal microbiota (IM) has been found to contribute to metabolic disorders that lead to excessive fat accumulation, systemic and chronic low-grade inflammation, and insulin resistance in the host. Current research highlights a pivotal interaction between IM and traditional Chinese medicine (TCM) in mitigating obesity-related diseases. Undeniably, IM stands as a central focus in TCM research aimed at preventing and treating obesity. Therefore, tracing the progress and trends in this field can offer valuable references and insights for future studies.

Methods

On June 17, 2023, we conducted a literature search on the topic of "IM and obesity in TCM" spanning the period from 2009 to 2023. We extracted the primary information of the publications, which includes complete records and reference citations, from the Science Citation Index Expanded (SCI-E) within the Web of Science Core Collection (WoSCC). To visualize and analyze the literature, we utilized CiteSpace and VOSviewer for bibliometric analysis.

Results

During the past fifteen years, a rapid increase in the number of publications has been observed. The cooperative networks demonstrate China, Beijing University of Chinese Medicine, and Food & Function as the most active countries, organizations, and journals in this field, respectively. Liu Bin has contributed the most publications. A paper by Xu Jia, published in 2014, holds the highest Local Citation Score (LCS). Analyses of keyword co-occurrence and reference co-citation indicate that the research hotspots of IM and obesity in TCM are primarily focused on the metabolic benefits driven by endogenous functional metabolic molecules generated by TCM regulation of IM. Other focal points include the mechanism by which TCM regulates IM to restore the intestinal mucosal barrier This is a provisional file, not the final typeset article, and manages the gut-organ axis, the metabolic advantages of acupuncture's regulation of IM, and the process by which Chinese medicine small molecules transform IM.

Conclusion

This research offers a comprehensive understanding of the current status, hotspots, and trends in global TCM research. Additionally, it provides a comprehensive summary and exploration of the latest advancements in this field, thereby emphasizing the essence of TCM more effectively.

Emerging Paradigms in Inflammatory Disease Management: Exploring Bioactive Compounds and the Gut Microbiota

The human gut microbiota is a complex ecosystem of mutualistic microorganisms that play a critical role in maintaining human health through their individual interactions and with the host. The normal gastrointestinal microbiota plays a specific physiological function in host immunomodulation, nutrient metabolism, vitamin synthesis, xenobiotic and drug metabolism, maintenance of structural and functional integrity of the gut mucosal barrier, and protection against various pathogens. Inflammation is the innate immune response of living tissues to injury and damage caused by infections, physical and chemical trauma, immunological factors, and genetic derangements. Most diseases are associated with an underlying inflammatory process, with inflammation mediated through the contribution of active immune cells. Current strategies to control inflammatory pathways include pharmaceutical drugs, lifestyle, and dietary changes. However, this remains insufficient. Bioactive compounds (BCs) are nutritional constituents found in small quantities in food and plant extracts that provide numerous health benefits beyond their nutritional value. BCs are known for their antioxidant, antimicrobial, anticarcinogenic, anti-metabolic syndrome, and anti-inflammatory properties. Bioactive compounds have been shown to reduce the destructive effect of inflammation on tissues by inhibiting or modulating the effects of inflammatory mediators, offering hope for patients suffering from chronic inflammatory disorders like atherosclerosis, arthritis, inflammatory bowel diseases, and neurodegenerative diseases. The aim of the present review is to summarise the role of natural bioactive compounds in modulating inflammation and protecting human health, for their safety to preserve gut microbiota and improve their physiology and behaviour.

Probiotic Supplementation, Hepatic Fibrosis, and the Microbiota Profile in Patients with Nonalcoholic Steatohepatitis: A Randomized Controlled Trial

BACKGROUND

Promising results in improvement of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis (NASH) have been identified following probiotic (PRO) treatment.

OBJECTIVES

To evaluate PRO supplementation on hepatic fibrosis, inflammatory and metabolic markers, and gut microbiota in NASH patients.

METHODS

In a double-blind, placebo-controlled clinical trial, 48 patients with NASH with a median age of 58 y and median BMI of 32.7 kg/m2 were randomly assigned to receive PROs (Lactobacillus acidophilus 1 × 109 colony forming units and Bifidobacterium lactis 1 × 109 colony forming units) or a placebo daily for 6 mo. Serum aminotransferases, total cholesterol and fractions, C-reactive protein, ferritin, interleukin-6, tumor necrosis factor-α, monocyte chemoattractant protein-1, and leptin were assessed. To evaluate liver fibrosis, Fibromax was used. In addition, 16S rRNA gene-based analysis was performed to evaluate gut microbiota composition. All assessments were performed at baseline and after 6 mo. For the assessment of outcomes after treatment, mixed generalized linear models were used to evaluate the main effects of the group-moment interaction. For multiple comparisons, Bonferroni correction was applied (α = 0.05/4 = 0.0125). Results for the outcomes are presented as mean and SE.

RESULTS

The AST to Platelet Ratio Index (APRI) score was the primary outcome that decreased over time in the PRO group. Aspartate aminotransferase presented a statistically significant result in the group-moment interaction analyses, but no statistical significance was found after the Bonferroni correction. Liver fibrosis, steatosis, and inflammatory activity presented no statistically significant differences between the groups. No major shifts in gut microbiota composition were identified between groups after PRO treatment.

CONCLUSIONS

Patients with NASH who received PRO supplementation for 6 mo presented improvement in the APRI score after treatment. These results draw attention to clinical practice and suggest that supplementation with PROs alone is not sufficient to improve enzymatic liver markers, inflammatory parameters, and gut microbiota in patients with NASH. This trial was registered at clinicaltrials.gov as NCT02764047.

Gut microbiota and obesity: an overview of microbiota to microbial-based therapies

The increasing prevalence of obesity and overweight is a significant public concern throughout the world. Obesity is a complex disorder involving an excessive amount of body fat. It is not just a cosmetic concern. It is a medical challenge that increases the risk of other diseases and health circumstances, such as diabetes, heart disease, high blood pressure and certain cancers. Environmental and genetic factors are involved in obesity as a significant metabolic disorder along with diabetes. Gut microbiota (GM) has a high potential for energy harvesting from the diet. In the current review, we aim to consider the role of GM, gut dysbiosis and significant therapies to treat obesity. Dietary modifications, probiotics, prebiotics, synbiotics compounds, using faecal microbiota transplant, and other microbial-based therapies are the strategies to intervene in obesity reducing improvement. Each of these factors serves through various mechanisms including a variety of receptors and compounds to control body weight. Trial and animal investigations have indicated that GM can affect both sides of the energy-balancing equation; first, as an influencing factor for energy utilisation from the diet and also as an influencing factor that regulates the host genes and energy storage and expenditure. All the investigated articles declare the clear and inevitable role of GM in obesity. Overall, obesity and obesity-relevant metabolic disorders are characterised by specific modifications in the human microbiota's composition and functions. The emerging therapeutic methods display positive and promising effects; however, further research must be done to update and complete existing knowledge.

Microbiota and plant-derived vesicles that serve as therapeutic agents and delivery carriers to regulate metabolic syndrome

The gut is a fundamental organ in controlling human health. Recently, researches showed that substances in the intestine can alter the course of many diseases through the intestinal epithelium, especially intestinal flora and exogenously ingested plant vesicles that can be transported over long distances to various organs. This article reviews the current knowledge on extracellular vesicles in modulating gut homeostasis, inflammatory response and numerous metabolic disease that share obesity as a co-morbidity. These complex systemic diseases that are difficult to cure, but can be managed by some bacterial and plant vesicles. Vesicles, due to their digestive stability and modifiable properties, have emerged as novel and targeted drug delivery vehicles for effective treatment of metabolic diseases.

A clinical trial about effects of prebiotic and probiotic supplementation on weight loss, psychological profile and metabolic parameters in obese subjects

INTRODUCTION

The management of obesity is difficult with many failures of lifestyle measures, hence the need to broaden the range of treatments prescribed. The aim of our work was to study the influence of pre and probiotics on weight loss psychological profile and metabolic parameters in obese patients.

METHODS

It is a clinical trial involving 45 obese patients, recruited from the Obesity Unit of the National Institute of Nutrition between March and August 2022 divided into three groups: diet only (low-carbohydrate and reduced energy diet), prebiotics (30 g of carob/day) and probiotics (one tablet containing Bifidobacterium longum, Lactobacillus helveticus, Lactococcus lactis, Streptococcus thermophilus/day). The three groups were matched for age, sex and BMI. Patients were seen after 1 month from the intervention. Anthropometric measures, biological parameters, dietary survey and psychological scores were performed.

RESULTS

The average age of our population was 48.73 ± 7.7 years, with a female predominance. All three groups showed a significant decrease in weight, BMI and waist circumference with p < .05. Only the prebiotic and probiotic group showed a significant decrease in fat mass (p = .001) and a significant increase in muscle strength with p = .008 and .004, but the differences were not significant between the three groups. Our results showed also a significant decrease in insulinemia and HOMA-IR in the prebiotic group compared to the diet-alone group (p = .03; p = .012) and the probiotic group showed a significant decrease in fasting blood glucose compared to the diet alone group (p = .02). A significant improvement in sleep quality was noted in the prebiotic group (p = .02), with a significant decrease in depression, anxiety and stress in all three groups.

CONCLUSIONS

The prescription of prebiotics and probiotics with the lifestyle measures seems interesting for the management of obesity especially if it is sarcopenic, in addition to the improvement of metabolic parameters and obesity-related psychiatric disorders.

TOTUM-63, a plant-based polyphenol-rich extract, improves glycaemic control in subjects with prediabetes or early stage newly-diagnosed type 2 diabetes in a randomized, double-blind, placebo-controlled trial

AIM

The plant-based polyphenol-rich extract TOTUM-63 improves glucose homeostasis in various preclinical models of obesity and type 2 diabetes (T2D). A pilot exploratory study showed that TOTUM-63 has good safety and tolerability profiles, and beneficial effects on postprandial glucose control in healthy individuals with overweight. The aim of this study was to assess the effects of TOTUM-63 on glycaemic control in individuals with prediabetes or early stage newly-diagnosed T2D (which does not require pharmacological treatment).

MATERIALS AND METHODS

This study was a multicentre, randomized, double-blind, placebo-controlled trial. Individuals with prediabetes or early stage newly-diagnosed T2D and with overweight/abdominal obesity received TOTUM-63 (5 g/day) or placebo for 6 months. The primary outcome was the change in fasting blood glucose.

RESULTS

Fifty-one participants (age: 57.1 ± 10 years; body mass index: 31.3 ± 5.7 kg.m² ; 35 women and 16 men) completed the study (n = 38 TOTUM-63, n = 13 placebo). After 6 months, blood glucose concentration after fasting and after the 2-h oral glucose tolerance test was reduced in the TOTUM-63-treated group compared with the placebo group (placebo-corrected difference between baseline and month 6: -0.71 mmol/L, p < .05, and -1.93 mmol/L, p < .05, respectively). TOTUM-63 was safe and well tolerated and significantly reduced body weight gain (-1.9 kg; p < .05), waist circumference (-4.5 cm; p < .001), circulating triglycerides (-0.54 mmol/L; p < .01) and low-density lipoprotein-cholesterol (-0.38 mmol/L; p < .05) compared with placebo.

CONCLUSIONS

TOTUM-63 lowered fasting blood glucose in participants with impaired fasting glycaemia and glucose intolerance. Moreover, TOTUM-63 showed a good safety and tolerability profile and improved several metabolic syndrome features. Therefore, TOTUM-63 is a promising candidate for T2D prevention.

The effect of synbiotic and vitamin D co-supplementation on body composition and quality of life in middle-aged overweight and obese women: A randomized controlled trial

BACKGROUND & AIMS

Obesity is a worldwide problem which has involved large populations. Since some dietary factors might modify obesity through various signaling pathways, the aim of this study was to investigate the effect of synbiotic plus vitamin D co-supplementation on body composition parameters and quality of life, in middle-aged overweight and obese women.

METHODS

A randomized, controlled, double-blinded trial was performed and 88 overweight and obese women were assigned to 4 groups (22 per group), receiving synbiotic plus vitamin D, synbiotic, vitamin D and placebo for 8 weeks. At the beginning and at the end of the trial, anthropometric indices, body composition indicators, physical activity level, dietary intake, and quality of life score were measured by trained nutritionists. Statistical analysis was performed with SPSS version 22.

RESULTS

The results showed significant difference between 4 groups in waist circumference (WC), fat mass (FM), body fat percentage (BFP) and visceral fat area (VFA) values after 8 weeks of treatment (P = 0.005, P = 0.007, P = 0.003, and P = 0.009, respectively), with the greatest reduction in synbiotic plus vitamin D group compare to placebo. No significant results were demonstrated between groups in relation to other body composition variables. In addition, there were no significant differences between the 4 groups regarding physical, mental and total aspects of life quality over time.

CONCLUSIONS

Our study demonstrated that synbiotic and vitamin D co-supplementation for 8 weeks, had favorable effect on various anthropometric indices and body composition indicators, but no desirable change in life quality score.

CLINICAL TRIAL REGISTRY

IRCT (registration no. IRCT20090822002365N25).

Gut Microbiota Dysbiosis Induced by a High-Fat Diet Increases Susceptibility to Atrial Fibrillation

BACKGROUND

Obesity is a significant risk factor for atrial fibrillation (AF), and the gut microbiota is closely related to obesity-induced diseases. However, whether the gut microbiota is involved in regulating obesity-induced AF has not been studied. This study investigated whether gut microbiota dysbiosis affects obesity-related AF.

METHODS

Fecal microbes derived from normal diet (ND)-fed and high-fat diet (HD)-fed mice were transplanted into those fed normally. Morphologic, biochemical, functional, histologic, electrophysiological studies, molecular analysis, 16S rRNA gene amplicon sequencing, and RNA-sequencing were performed.

RESULTS

Transplantation of the HD gut microbes in ND-maintained (THD) mice led to a significant increase in the susceptibility to AF. Gut microbiota analysis showed a significant increase in Desulfovibrionaceae, which generated metabolic endotoxemia in THD mice. Transplantation with HD microbes also resulted in significantly increased levels of circulating lipopolysaccharide (LPS), significant disruption in the histologic architecture of the intestinal tissue, and significantly increased proinflammatory cytokines in the left atrium, indicating that atrial inflammation likely contributed to AF susceptibility. RNA-sequencing showed that the THD group had enhanced activation of ferroptosis and TLR4/NF-κB/NLRP3 inflammasome signalling pathway. Inhibiting the ferroptosis or NLRP3 inflammasome signalling pathway significantly improved atrial fibrosis and reduced susceptibility to obesity-related gut dysbiosis-induced AF.

CONCLUSIONS

This study provides evidence showing an original causal role of gut microbiota dysbiosis in the pathogenesis of obesity-related AF, which showed elevated LPS and dysregulation of atrial pathologic remodelling by activating ferroptosis and the TLR4/NF-κB/NLRP3 inflammasome signalling pathway.

Tackling the Future Pandemics: Broad-Spectrum Antiviral Agents (BSAAs) Based on A-Type Proanthocyanidins

A-type proanthocyanidins (PAC-As) are plant-derived natural polyphenols that occur as oligomers or polymers of flavan-3-ol monomers, such as (+)-catechin and (-)-epicatechin, connected through an unusual double A linkage. PAC-As are present in leaves, seeds, flowers, bark, and fruits of many plants, and are thought to exert protective natural roles against microbial pathogens, insects, and herbivores. Consequently, when tested in isolation, PAC-As have shown several biological effects, through antioxidant, antibacterial, immunomodulatory, and antiviral activities. PAC-As have been observed in fact to inhibit replication of many different human viruses, and both enveloped and non-enveloped DNA and RNA viruses proved sensible to their inhibitory effect. Mechanistic studies revealed that PAC-As cause reduction of infectivity of viral particles they come in contact with, as a result of their propensity to interact with virion surface capsid proteins or envelope glycoproteins essential for viral attachment and entry. As viral infections and new virus outbreaks are a major public health concern, development of effective Broad-Spectrum Antiviral Agents (BSAAs) that can be rapidly deployable even against future emerging viruses is an urgent priority. This review summarizes the antiviral activities and mechanism of action of PAC-As, and their potential to be deployed as BSAAs against present and future viral infections.

Synergic interactions between berry polyphenols and gut microbiota in cardiovascular diseases

Now a days, scientific community has been taking initiatives to decrease burden of metabolic disorders including diabetes mellitus, chronic hypertension, cardiovascular diseases and many others. Many nutraceuticals and functional food have a crucial function in preventing and decreasing burden of chronic diseases. Main purpose of the study was to relate association between mechanism of gut microbiota effecting cardiovascular diseases, moreover, to find out advantageous effects of berry polyphenols on gut microbiota and cardiovascular diseases. To summarize, we explore literature for beneficial effects of berry polyphenols by using multiple search engines including Google Scholar, Science Direct and PubMed. Original research article, review articles, experimental trials (human and animal studies) and abstract were also included in the current study based on relevancy to the characteristics of berries and their potential benefit on human health. This detailed review revealed that all classes of berries and their metabolites possess a definite impact on human health by preventing onset of chronic diseases by its anti-inflammatory property, thus, consider as one of the beneficial natural compounds that can be consumed on daily basis to prevent various disorders. There is also a positive association between berry polyphenols and modulation of gut microbiota and their metabolites, furthermore, showed a relationship between gut microbiome and incidence of cardiovascular disease.

The Role of Prunes in Modulating Inflammatory Pathways to Improve Bone Health in Postmenopausal Women

The prevalence of osteoporosis among women aged 50 y and older is expected to reach 13.6 million by 2030. Alternative nonpharmaceutical agents for osteoporosis, including nutritional interventions, are becoming increasingly popular. Prunes (dried plums; Prunus domestica L.) have been studied as a potential whole-food dietary intervention to mitigate bone loss in preclinical models of osteoporosis and in osteopenic postmenopausal women. Sixteen preclinical studies using in vivo rodent models of osteopenia or osteoporosis have established that dietary supplementation with prunes confers osteoprotective effects both by preventing and reversing bone loss. Increasing evidence from 10 studies suggests that, in addition to antiresorptive effects, prunes exert anti-inflammatory and antioxidant effects. Ten preclinical studies have found that prunes and/or their polyphenol extracts decrease malondialdehyde and NO secretion, increase antioxidant enzyme expression, or suppress NF-κB activation and proinflammatory cytokine production. Two clinical trials have investigated the impact of dried plum consumption (50-100 g/d for 6-12 mo) on bone health in postmenopausal women and demonstrated promising effects on bone mineral density and bone biomarkers. However, less is known about the impact of prune consumption on oxidative stress and inflammatory mediators in humans and their possible role in modulating bone outcomes. In this review, the current state of knowledge on the relation between inflammation and bone health is outlined. Findings from preclinical and clinical studies that have assessed the effect of prunes on oxidative stress, inflammatory mediators, and bone outcomes are summarized, and evidence supporting a potential role of prunes in modulating inflammatory and immune pathways is highlighted. Key future directions to bridge the knowledge gap in the field are proposed.

The effects of Clostridium butyricum on Ira rabbit growth performance, cecal microbiota and plasma metabolome

Clostridium butyricum (C. butyricum) can provide many benefits for animals’ growth performance and gut health. In this study, we investigated the effects of C. butyricum on the growth performance, cecal microbiota, and plasma metabolome in Ira rabbits. A total of 216 Ira rabbits at 32 days of age were randomly assigned to four treatments supplemented with basal diets containing 0 (CG), 200 (LC), 400 (MC), and 600 mg/kg (HC) C. butyricum for 35 days, respectively. In comparison with the CG group, C. butyricum supplementation significantly improved the average daily gain (ADG) and feed conversion rate (FCR) at 53 and 67 days of age (P < 0.05) and digestibilities of crude protein (CP) and crude fiber (CF) at 67 days of age (P < 0.05). The cellulase activity in the HC group was higher respectively by 50.14 and 90.13% at 53 and 67 days of age, than those in the CG groups (P < 0.05). Moreover, at 67 days of age, the diet supplemented with C. butyricum significantly increased the relative abundance of Verrucomicrobia at the phylum level (P < 0.05). Meanwhile, the concentrations of different metabolites, such as amino acids and purine, were significantly altered by C. butyricum (P < 0.05). In addition, 10 different genera were highly correlated with 52 different metabolites at 53-day-old and 6 different genera were highly correlated with 18 different metabolites at 67-day-old Ira rabbits. These findings indicated that the C. butyricum supplementation could significantly improve the growth performance by modifying the cecal microbiota structure and plasma metabolome of weaned Ira rabbits.

Impact of Blueberry Consumption on the Human Fecal Bileacidome: A Pilot Study of Bile Acid Modulation by Freeze-Dried Blueberry

Cholesterol-derived bile acids (BAs) affect numerous physiological functions such as glucose homeostasis, lipid metabolism and absorption, intestinal inflammation and immunity, as well as intestinal microbiota diversity. Diet influences the composition of the BA pool. In the present study, we analyzed the impact of a dietary supplementation with a freeze-dried blueberry powder (BBP) on the fecal BA pool composition. The diet of 11 men and 13 women at risk of metabolic syndrome was supplemented with 50 g/day of BBP for 8 weeks, and feces were harvested before (pre) and after (post) BBP consumption. BAs were profiled using liquid chromatography coupled with tandem mass spectrometry. No significant changes in total BAs were detected when comparing pre- vs. post-BBP consumption samples. However, post-BBP consumption samples exhibited significant accumulations of glycine-conjugated BAs (p = 0.04), glycochenodeoxycholic (p = 0.01), and glycoursodeoxycholic (p = 0.01) acids, as well as a significant reduction (p = 0.03) in the secondary BA levels compared with pre-BBP feces. In conclusion, the fecal bileacidome is significantly altered after the consumption of BBP for 8 weeks. While additional studies are needed to fully understand the underlying mechanisms and physiological implications of these changes, our data suggest that the consumption of blueberries can modulate toxic BA elimination.

Cellular Antioxidant Effect of an Aronia Extract and Its Polyphenolic Fractions Enriched in Proanthocyanidins, Phenolic Acids, and Anthocyanins

Oxidative stress and chronic inflammation contribute to some chronic diseases. Aronia berries are rich in polyphenols. The aim of the present study was to characterize the cellular antioxidant effect of an aronia extract to reflect the potential physiological in vivo effect. Cellular in vitro assays in three cell lines (Caco-2, HepG2, and SH-SY5Y) were used to measure the antioxidant effect of AE, in three enriched polyphenolic fractions (A1: anthocyanins and phenolic acids; A2: oligomeric proanthocyanidins; A3: polymeric proanthocyanidins), pure polyphenols and microbial metabolites. Both direct (intracellular and membrane radical scavenging, catalase-like effect) and indirect (NRF2/ARE) antioxidant effects were assessed. AE exerted an intracellular free radical scavenging activity in the three cell lines, and A2 and A3 fractions showed a higher effect in HepG2 and Caco-2 cells. AE also exhibited a catalase-like activity, with the A3 fraction having a significant higher activity. Only A1 fraction activated the NRF2/ARE pathway. Quercetin and caffeic acid are the most potent antioxidant polyphenols, whereas cyanidin and 5-(3',4'-dihydroxyphenyl)-γ-valerolactone showed the highest antioxidant effect among polyphenol metabolites. AE rich in polyphenols possesses broad cellular antioxidant effects, and proanthocyanidins are major contributors. Polyphenol metabolites may contribute to the overall antioxidant effect of such extract in vivo.

Grape seed and skin extract, a potential prebiotic with anti-obesity effect through gut microbiota modulation

Background

Obesity is a worldwide health problem and a significant risk factor for diabetes and cardiovascular diseases. Gut microbiota (GM) plays an essential role in obesity, and prebiotics such as polyphenols could be one way to improve microbial dysbiosis-induced obesity.

Objective

This study was designed to assess the effectiveness of grape seed and skin extract (GSSE), and/or orlistat on obese rats fed with high fat diet by targeting GM modulations. The impact of treatments was also studied in non-obese rats.

Material and methods

Rats were rendered obese or kept with a standard diet for three months. Then they were treated either with GSSE or orlistat or with the combined treatment (GSOR) during three months and then sacrificed. Adipose tissues, blood and faeces were collected and analyzed.

Results

In obese rats and to a lesser extent in non-obese rats, treatments decreased the weight of various adipose tissues and the serum levels of cholesterol, LDL, triglycerides, lipase, and CRP and increased HDL and adiponectin. GSOR treatment was even more efficient that orlistat. Obese rats had less GM diversity than non-obese rats and orlistat reduced it even more. However, diversity was restored with GSSE and GSOR treatments. Potential pathogenic Streptococcus alactolyticus/gallolyticus species were greatly increased in obese rats and drastically reduced with the treatments, as wells as other potential pathobionts.

Conclusions

GSSE exerts beneficial effects in obese rats and restores, at least partially, the observed dysbiosis. GSOR induced the highest beneficial effect. Moreover, the various treatments could also enhance physiological and GM modifications in non obese rats.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13099-022-00505-0.

Curcuminoids for Metabolic Syndrome: Meta-Analysis Evidences Toward Personalized Prevention and Treatment Management

The metabolic syndrome (MS) is a multifactorial syndrome associated with a significant economic burden and healthcare costs. MS management often requires multiple treatments (polydrug) to ameliorate conditions such as diabetes mellitus, insulin resistance, obesity, cardiovascular diseases, hypertension, and non-alcoholic fatty liver disease (NAFLD). However, various therapeutics and possible drug-drug interactions may also increase the risk of MS by altering lipid and glucose metabolism and promoting weight gain. In addition, the medications cause side effects such as nausea, flatulence, bloating, insomnia, restlessness, asthenia, palpitations, cardiac arrhythmias, dizziness, and blurred vision. Therefore, is important to identify and develop new safe and effective agents based on a multi-target approach to treat and manage MS. Natural products, such as curcumin, have multi-modalities to simultaneously target several factors involved in the development of MS. This review discusses the recent preclinical and clinical findings, and up-to-date meta-analysis from Randomized Controlled Trials regarding the effects of curcumin on MS, as well as the metabonomics and a pharma-metabolomics outlook considering curcumin metabolites, the gut microbiome, and environment for a complementary personalized prevention and treatment for MS management.

The Nutrition-Microbiota-Physical Activity Triad: An Inspiring New Concept for Health and Sports Performance

The human gut microbiota is currently the focus of converging interest in many diseases and sports performance. This review presents gut microbiota as a real “orchestra conductor” in the host’s physio(patho)logy due to its implications in many aspects of health and disease. Reciprocally, gut microbiota composition and activity are influenced by many different factors, such as diet and physical activity. Literature data have shown that macro- and micro-nutrients influence gut microbiota composition. Cumulative data indicate that gut bacteria are sensitive to modulation by physical activity, as shown by studies using training and hypoactivity models. Sports performance studies have also presented interesting and promising results. Therefore, gut microbiota could be considered a “pivotal” organ for health and sports performance, leading to a new concept: the nutrition-microbiota-physical activity triad. The next challenge for the scientific and medical communities is to test this concept in clinical studies. The long-term aim is to find the best combination of the three elements of this triad to optimize treatments, delay disease onset, or enhance sports performance. The many possibilities offered by biotic supplementation and training modalities open different avenues for future research.

Tea Polyphenols Prevent and Intervene in COVID-19 through Intestinal Microbiota

Although all countries have taken corresponding measures, the coronavirus disease 2019 (COVID-19) is still ravaging the world. To consolidate the existing anti-epidemic results and further strengthen the prevention and control measures against the new coronavirus, we are now actively pioneering a novel research idea of regulating the intestinal microbiota through tea polyphenols for reference. Although studies have long revealed the regulatory effect of tea polyphenols on the intestinal microbiota to various gastrointestinal inflammations, little is known about the prevention and intervention of COVID-19. This review summarizes the possible mechanism of the influence of tea polyphenols on COVID-19 mediated by the intestinal microbiota. In this review, the latest studies of tea polyphenols exhibiting their own antibacterial and anti-inflammatory activities and protective effects on the intestinal mucosal barrier are combed through and summarized. Among them, (−)-epigallocatechin-3-gallate (EGCG), one of the main monomers of catechins, may be activated as nuclear factor erythroid 2 p45-related factor 2 (Nrf2). The agent inhibits the expression of ACE2 (a cellular receptor for SARS-CoV-2) and TMPRSS2 to inhibit SARS-CoV-2 infection, inhibiting the life cycle of SARS-CoV-2. Thus, preliminary reasoning and judgments have been made about the possible mechanism of the effect of tea polyphenols on the COVID-19 control and prevention mediated by the microbiota. These results may be of great significance to the future exploration of specialized research in this field.

Influence of 8-week daily consumption of a new product combining green coffee hydroxycinnamates and beta-glucans on polyphenol bioavailability in subjects with overweight and obesity

Nutraceuticals based on plant extracts rich in polyphenols, as well as dietary fibres, are new means to fight overweight/obesity and associated diseases. However, to understand the potential effects of polyphenols on health it is critical to study their bioavailability and metabolic fate. Consumption of a green coffee phenolic extract (GCPE) in combination with oat beta-glucan (BG) could affect the pharmacokinetic profile of the main polyphenols present in coffee (hydroxycinnamates). Moreover, the regular intake of the combination could also induce changes. Nine overweight men and women consumed a novel nutraceutical product containing 300 mg of green coffee hydroxycinnamic acids and 2.5 g of BG twice a day for 8 weeks. A pharmacokinetic study was carried out in blood and urine samples taken before (baseline) and at week 8 after the nutraceutical intervention, collecting samples at different times in a 0-24 h interval. Faecal samples were also obtained at 0 and 24 h after the intake of the nutraceutical at baseline and week 8. Phenolic metabolites were analysed by LC-MS-QToF. Results showed that polyphenols were differentially absorbed and extensively metabolized throughout the gastrointestinal tract. An apparent reduction in the excretion of small intestinal metabolites was accompanied by a tendency to increase colonic metabolites after sustained intake (p = 0.052). In conclusion, continued consumption of the GCPE/BG nutraceutical appears to enhance the absorption of hydroxycinnamates by increasing the colonic bioavailability of their derived metabolites compared to baseline, although the regular intake of the nutraceutical did not modify the metabolite profile in any of the biological samples.

The gut microbiota of non-obese Japanese pregnant women with gestational diabetes mellitus

Recent evidence has shown that gut microbiota dysbiosis is associated with development of gestational diabetes mellitus (GDM). However, the gut microbiota composition of non-obese women with GDM, which accounts for a relatively large percentage of Asian GDM, is unknown. We investigated the characteristics of gut microbiota of Japanese pregnant women with GDM. Fecal samples from Japanese pregnant women with GDM (n=20) and normal glucose tolerance (NGT, n=16) were collected at the time of GDM diagnosis (T1), at 35-37 weeks of gestation (T2), and at 4 weeks postpartum (T3). Gut microbiota composition was characterized from fecal DNA by sequencing of 16S rRNA genes. Serum samples were collected late in the third trimester, and the circulating levels of adiponectin and IL-6 were measured by ELISA. At the genus level, Peptostreptococcaceae Romboutsia was enriched in GDM women at T1 (p=0.008) and T2 (p=0.047). The women with lower serum adiponectin tended to have more Romboutsia. The Shannon index was significantly lower in the GDM women at T3 than in the NGT women (p=0.008), and that of the GDM women decreased significantly from T2 to T3 (p=0.02). No significant difference in bacterial community structure was found in a beta diversity analysis. The non-obese GDM women (body mass index <25.0 kg/m²) showed a lower abundance of Coriobacteriaceae Collinsella at T1 (p=0.03) and higher abundance of Akkermansia at T2 (p=0.04) than the normal control. The non-obese GDM women had the distinctive gut microbiota profiles. Analysis of gut microbiota is potentially useful for risk assessment of GDM in non-obese pregnant women.

Camu Camu effects on microbial translocation and systemic immune activation in ART-treated people living with HIV: protocol of the single-arm non-randomised Camu Camu prebiotic pilot study (CIHR/CTN PT032)

INTRODUCTION

Despite the success of antiretroviral therapy (ART) in transforming HIV disease into a chronic infection, people living with HIV (PLWH) remain at risk for various non-AIDS inflammatory comorbidities. Risk of non-AIDS comorbidities is associated with gut dysbiosis, epithelial gut damage and subsequent microbial translocation, and increased activation of both circulating CD4+ and CD8+ T-cells. Therefore, in addition to ART, novel gut microbiota-modulating therapies could aid in reducing inflammation and immune activation, gut damage, and microbial translocation. Among various gut-modulation strategies under investigation, the Amazonian fruit Camu Camu (CC) presents itself as a prebiotic candidate based on its anti-inflammatory and antioxidant properties in animal models and tobacco smokers.

METHOD AND ANALYSIS

A total of 22 PLWH on ART for more than 2 years, with a viral load <50 copies/mL, a CD4 +count >200 and a CD4+/CD8 +ratio <1 (suggesting increased inflammation and risk for non-AIDS comorbidities), will be recruited in a single arm, non-randomised, interventional pilot trial. We will assess tolerance and effect of supplementation with CC in ART-treated PLWH on reducing gut damage, microbial translocation, inflammation and HIV latent reservoir by various assays.

ETHICS AND DISSEMINATION

The Canadian Institutes of Health Research (CIHR)/Canadian HIV Trials Network (CTN) pilot trial protocol CTNPT032 was approved by the Natural and Non-prescription Health Products Directorate of Health Canada and the research ethics board of the McGill university Health Centre committee (number 2020-5903). Results will be made available as free access through publications in peer-reviewed journals and through the CIHR/CTN website.

TRIAL REGISTRATION NUMBER

NCT04058392.

Curcumin and Weight Loss: Does It Work?

Obesity is a global health problem needing urgent research. Synthetic anti-obesity drugs show side effects and variable effectiveness. Thus, there is a tendency to use natural compounds for the management of obesity. There is a considerable body of knowledge, supported by rigorous experimental data, that natural polyphenols, including curcumin, can be an effective and safer alternative for managing obesity. Curcumin is a is an important compound present in Curcuma longa L. rhizome. It is a lipophilic molecule that rapidly permeates cell membrane. Curcumin has been used as a pharmacological traditional medicinal agent in Ayurvedic medicine for ∼6000 years. This plant metabolite doubtless effectiveness has been reported through increasingly detailed in vitro, in vivo and clinical trials. Regarding its biological effects, multiple health-promoting, disease-preventing and even treatment attributes have been remarkably highlighted. This review documents the status of research on anti-obesity mechanisms and evaluates the effectiveness of curcumin for management of obesity. It summarizes different mechanisms of anti-obesity action, associated with the enzymes, energy expenditure, adipocyte differentiation, lipid metabolism, gut microbiota and anti-inflammatory potential of curcumin. However, there is still a need for systematic and targeted clinical studies before curcumin can be used as the mainstream therapy for managing obesity.

Anti-obesity natural products and gut microbiota

The link between gut microbiota and obesity or other metabolic syndromes is growing increasingly clear. Natural products are appreciated for their beneficial health effects in humans. Increasing investigations demonstrated that the anti-obesity bioactivities of many natural products are gut microbiota dependent. In this review, we summarized the current knowledge on anti-obesity natural products acting through gut microbiota according to their chemical structures and signaling metabolites. Manipulation of the gut microbiota by natural products may serve as a potential therapeutic strategy to prevent obesity.

Cinnamomum verum-derived bioactives-functionalized gold nanoparticles for prevention of obesity through gut microbiota reshaping

Existing drugs have limited success in managing obesity in human due to their low efficacy and severe side-effects. Surface-modified gold nanoparticles have now received considerable attention of researchers for efficient biomedical applications owing to their superior uptake by cells, biocompatibility, hydrophilicity and non-immunogenicity. Here we prepared Cinnamomum verum derived bioactives-functionalized gold nanoparticles (Au@P-NPs) and assessed their impact on obesity and related immune-metabolic complications in high-fat diet (HFD)-induced obese mice using metabolic experiments along with 16S RNA gene-based gut microbial profiling and faecal microbiota transplantation (FMT). Au@P-NPs treatment prevented weight gain, decreased fat deposition, reduced metabolic inflammation and endotoxaemia in HFD-fed mice. Au@P-NPs-treated group exhibited better glucose tolerance and insulin sensitivity than HFD-fed control mice, and got completely protected against hepatic steatosis. These impacts were related to increased energy expenditure and enhanced Ucp1 expression in the brown adipose tissues of Au@P-NPs-administered animals, which strongly linked with the mRNA expression of the membrane bile acid receptor TGR5. Treatment of HFD-fed animals with Au@P-NPs altered plasma bile acid profile, and increased Akkermansia muciniphila and decreased Lactobacillus populations in the faeces. Au@P-NPs-treated animals revealed altered plasma bile acid profile, and increased Akkermansia muciniphila and decreased Lactobacillus populations in the faeces. FMT experiments showed lesser weight gain and greater energy expenditure in the mice fed with faecal suspension from Au@P-NPs-treated animals than that from HFD-fed mice. These results clearly establish that gold nanoparticles functionalized with bioactive compounds of C. verum have high potential to be an anti-obesity drug.

Polyphenols-Gut Microbiota Interrelationship: A Transition to a New Generation of Prebiotics

The present review summarizes the studies carried out on this topic in the last five years. According to the new definitions, among all the compounds included in the group of prebiotics, polyphenols are probably the most important secondary metabolites produced by the plant kingdom. Many of these types of polyphenols have low bioavailability, therefore reaching the colon in unaltered form. Once in the colon, these compounds interact with the intestinal microbes bidirectionally by modulating them and, consequently, releasing metabolites. Despite much research on various metabolites, little is known about the chemistry of the metabolic routes used by different bacteria species. In this context, this review aims to investigate the prebiotic effect of polyphenols in preclinical and clinical studies, highlighting that the consumption of polyphenols leads to an increase in beneficial bacteria, as well as an increase in the production of valuable metabolites. In conclusion, there is much evidence in preclinical studies supporting the prebiotic effect of polyphenols, but further clinical studies are needed to investigate this effect in humans.

Ulcerative colitis results in differential metabolism of cranberry polyphenols by the colon microbiome in vitro

The microbiome plays a major role in polyphenol metabolism, producing metabolites that are bioavailable and potentially more bioactive than the compounds from which they are derived. However, the microbiome can vary among individuals, and especially for those with co-morbidities, such as ulcerative colitis. In subjects with ulcerative colitis, the consequence of a 'dysbiotic' microbiome is characterized by decreased diversity of microbiota that may impact their capability to metabolize polyphenols into bioavailable metabolites. On this premise, the microbiome metabolism of cranberry polyphenols between healthy individuals and those with ulcerative colitis was compared in vitro. Fecal samples from volunteers, with or without diagnosed ulcerative colitis, were cultured anaerobically in the presence of cranberry polyphenols. The resulting metabolites were then quantified via LC-ESI-MS/MS. 16S rRNA metagenomics analysis was also utilized to assess differences in microbiota composition between healthy and ulcerative colitis microbiomes and the modulatory effects of cranberry polyphenols on microbiota composition. Healthy microbiomes produced higher (p < 0.05) concentrations of 5-(3',4'-dihydroxyphenyl)-gamma-valerolactone and 3-hydroxyphenylacetic acid in comparison to ulcerative colitis microbiomes. Additionally, healthy microbiomes contained a higher (p < 0.05) abundance of Ruminococcaceae, which could explain their ability to produce higher concentrations of cranberry polyphenol metabolites. Health status and the presence of cranberry polyphenols also significantly impacted the production of several short-chain and branched-chain fatty acids. These results suggest that efficiency of polyphenol metabolism is dependent on microbiota composition and future works should include metabolite data to account for inter-individual differences in polyphenol metabolism.

An In Vitro Protocol to Study the Modulatory Effects of a Food or Biocompound on Human Gut Microbiome and Metabolome

The gut microbiota plays a key role in gastrointestinal immune and metabolic functions and is influenced by dietary composition. An in vitro protocol simulating the physiological conditions of the digestive system helps to study the effects of foods/biocompounds on gut microbiome and metabolome. The Dynamic-Colonic Gastrointestinal Digester consists of five interconnected compartments, double jacket vessels that simulate the physiological conditions of the stomach, the small intestine and the three colonic sections, which are the ascending colon, transverse colon and descending colon. Human faeces are required to reproduce the conditions and culture medium of the human colon, allowing the growth of the intestinal microbiota. After a stabilization period of 12 days, a food/biocompound can be introduced to study its modulatory effects during the next 14 days (treatment period). At the end of the stabilization and treatment period, samples taken from the colon compartments are analysed. The 16S rRNA gene analysis reveals the microbiota composition. The untargeted metabolomics analysis gives more than 10,000 features (metabolites/compounds). The present protocol allows in vitro testing of the modulatory effects of foods or biocompounds on gut microbiota composition and metabolic activity.

In vitro co-metabolism of epigallocatechin-3-gallate (EGCG) by the mucin-degrading bacterium Akkermansia muciniphila

Akkermansia muciniphila is a Gram-negative bacterium that resides within the gut mucus layer, and plays an important role in promoting gut barrier integrity, modulating the immune response and inhibiting gut inflammation. Growth stimulation of A. muciniphila by polyphenols including epigallocatechin-3-gallate (EGCG) from difference sources is well-documented. However, no published in vitro culture data on utilization of polyphenols by A. muciniphila are available, and the mechanism of growth-stimulating prebiotic effect of polyphenols on it remains unclear. Here in vitro culture studies have been carried out on the metabolism of EGCG by A. muciniphila in the presence of either mucin or glucose. We found that A. muciniphila did not metabolize EGCG alone but could co-metabolize it together with both these substrates in the presence of mineral salts and amino acids for mucin and protein sources for glucose. Our metabolomic data show that A. muciniphila converts EGCG to gallic acid, epigallocatechin, and (-)-epicatechin through ester hydrolysis. The (-)-epicatechin formed is then further converted to hydroxyhydroquinone. Co-metabolism of A. muciniphila of EGCG together with either mucin or glucose promoted substantially its growth, which serves as a further demonstration of the growth-promoting effect of polyphenols on A. muciniphila and provides an important addition to the currently available proposed mechanisms of polyphenolic prebiotic effects on A. muciniphila.

Gut microbiota-based vaccination engages innate immunity to improve blood glucose control in obese mice

Objective

Obesity and diabetes increase circulating levels of microbial components derived from the gut microbiota. Individual bacterial factors (i.e., postbiotics) can have opposing effects on blood glucose.

Methods

We tested the net effect of gut bacterial extracts on blood glucose in mice using a microbiota-based vaccination strategy.

Results

Male and female mice had improved glucose and insulin tolerance five weeks after a single subcutaneous injection of a specific dose of a bacterial extract obtained from the luminal contents of the upper small intestine (SI), lower SI, or cecum. Injection of mice with intestinal extracts from germ-free mice revealed that bacteria were required for a microbiota-based vaccination to improve blood glucose control. Vaccination of Nod1^−/−, Nod2^−/−, and Ripk2^−/− mice showed that each of these innate immune proteins was required for bacterial extract injection to improve blood glucose control. A microbiota-based vaccination promoted an immunoglobulin-G (IgG) response directed against bacterial extract antigens, where subcutaneous injection of mice with the luminal contents of the lower SI elicited a bacterial extract-specific IgG response that is compartmentalized to the lower SI of vaccinated mice. A microbiota-based vaccination was associated with an altered microbiota composition in the lower SI and colon of mice. Lean mice only required a single injection of small intestinal-derived bacterial extract, but high fat diet (HFD)-fed, obese mice required prime-boost bacterial extract injections for improvements in blood glucose control.

Conclusions

Subversion of the gut barrier by vaccination with a microbiota-based extract engages innate immunity to promote long-lasting improvements in blood glucose control in a dose-dependent manner.

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Subcutaneous injection of gut bacterial extracts improved blood glucose control in mice.

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Microbiota-based vaccination engaged NOD1-NOD2-RIPK2 to alter blood glucose.

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Microbiota-based vaccination promoted a proximal gut IgG response.

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Microbiota-based vaccination altered the composition of the gut microbiome.

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Obese mice required prime-boost injections to improve blood glucose control.

Food phenolics stimulate adipocyte browning via regulating gut microecology

Fat browning has piqued the interest of researchers as a potential target for treating obesity and related metabolic disorders. Recruitment of brown adipocytes leads to enhanced energy dissipation and reduced adiposity, thus facilitating the maintenance of metabolic homeostasis. Evidence is increasing to support the crucial roles of polyphenols and gut microecology in turning fat "brown". However, it is not clear whether the intestinal microecology is involved in polyphenol-mediated regulation of adipose browning, so this concept is worthy of exploration. In this review, we summarize the current knowledge, mostly from studies with murine models, supporting the concept that the effects of food phenolics on brown fat activation and white fat browning can be attributed to their regulatory actions on gut microecology, including microbial community profile, gut metabolites, and gut-derived hormones. Furthermore, the potential underlying pathways involved are also discussed. Basically, understanding gut microecology paves the way to determine the underlying roles and mechanisms of food phenolics in adipose browning.

Mutual effects of free and nanoencapsulated phenolic compounds on human microbiota

Phenolic compounds (PC) have many health benefits such as antioxidant, anticarcinogenic, neuroprotective, and anti-inflammatory activities. All of these activities depend on their chemical structures and their interaction with biological targets in the body. PC occur naturally in polymerized form, linked to glycosides and requires metabolic transformation from their ingestion to their absorption. The gut microbiota can transform PC into more easily absorbed metabolites. The PC, in turn, have prebiotic and antimicrobial actions on the microbiota. Despite this, their low oral bioavailability still compromises biological performance. Therefore, the use of nanocarriers has been demonstrated to be a useful strategy to improve PC absorption and, consequently, their health effects. Nanotechnology is an excellent alternative able to overcome the limits of oral bioavailability of PC, since it offers protection from degradation during their passage through the gastrointestinal tract. Moreover, nanotechnology is also capable of promoting controlled PC release and modulating the interaction between PC and the microbiota. However, little is known about the impact of the nanotechnology on PC effects on the gut microbiota. This review highlights the use of nanotechnology for PC delivery on gut microbiota, focusing on the ability of such formulations to enhance oral bioavailability by applying nanocarriers (polymeric nanoparticles, nanostructured lipid carriers, solid lipid nanoparticles). In addition, the effects of free and nanocarried PC or nanocarriers per se on gut microbiota are also described.

A Cranberry Concentrate Decreases Adhesion and Invasion of Escherichia coli (AIEC) LF82 In Vitro

While many beneficial host-microbiota interactions have been described, imbalanced microbiota in the gut is speculated to contribute to the progression and recurrence of chronic inflammatory diseases such as Crohn's disease (CD). This in vitro study evaluated the impact of a cranberry concentrate Type M (CTM) on adherent-invasive Escherichia coli (AIEC) LF82, a pathobiont associated with CD. Different stages of pathogenic infection were investigated: (i) colonization of the mucus layer, and (ii) adhesion to and (iii) invasion of the epithelial cells. Following 48 h of fecal batch incubation, 0.5 and 1 mM of CTM significantly altered AIEC LF82 levels in a simulated mucus layer, resulting in a decrease of 50.5% in the untreated blank, down to 43.0% and 11.4%, respectively. At 1 mM of CTM, the significant decrease in the levels of AIEC LF82 coincided with a stimulation of the metabolic activity of the background microbiota. The increased levels of health-associated acetate (+7.9 mM) and propionate levels (+3.5 mM) suggested selective utilization of CTM by host microorganisms. Furthermore, 1 mM of both fermented and unfermented CTM decreased the adhesion and invasion of human-derived epithelial Caco-2 cells by AIEC LF82. Altogether, this exploratory in vitro study demonstrates the prebiotic potential of CTM and supports its antipathogenic effects through direct and/or indirect modulation of the gut microbiome.

Computational Analysis Illustrates the Mechanism of Qingfei Paidu Decoction in Blocking the Transition of COVID-19 Patients from Mild to Severe Stage

BACKGROUND

The epidemic of SARS-CoV-2 has made COVID-19 a serious threat to human health around the world. The severe infections of SARS-CoV-2 are usually accompanied by higher mortality. Although the Qingfei Paidu Decoction (QFPDD) has been proved to be effective in blocking the transition of COVID-19 patients from mild to severe stage, its mechanism remains unclear.

OBJECTIVE

This study aims to explore the mechanism of QFPDD in blocking the transition of COVID-19 patients from mild to severe stage.

MATERIALS AND METHODS

In the process of screening active ingredients, oral bioavailability (OB) and drug likeness (DL) are key indicators, which can help to screen out pivotal compounds. Therefore, with the criteria of OB≥30% and DL≥0.18 , we searched active ingredients of QFPDD in the Traditional Chinese Medicine Systems Pharmacology (TCMSP, https://tcmspw.com/) by using its 21 herbs as keywords.

RESULTS

We filtered out 6 pivotal ingredients from QFPDD by using the bioinformatics method, namely quercetin, luteolin, berberine, hederagenin, shionone and kaempferol, which can inhibit the highly expressed genes (i.e. CXCR4, ICAM1, CXCL8, CXCL10, IL6, IL2, CCL2, IL1B, IL4, IFNG) in severe COVID-19 patients. By performing KEGG enrichment analysis, we found seven pathways, namely TNF signaling pathway, IL-17 signaling pathway, Toll-like receptor signaling pathway, NF-kappa B signaling pathway, HIF-1 signaling pathway, JAK-STAT signaling pathway, and Th17 cell differentiation, by which QFPDD could block the transition of COVID-19 patients from mild to severe stage.

CONCLUSION

QFPDD can prevent the deterioration of COVID-19 in the following mechanisms, i.e. inhibiting SARS-CoV-2 invasion and replication, anti-inflammatory and immune regulation, and repairing body damage. These results will be helpful for the prevention and treatment of COVID-19.

Distinct Impact of Natural Sugars from Fruit Juices and Added Sugars on Caloric Intake, Body Weight, Glycaemia, Oxidative Stress and Glycation in Diabetic Rats

Although fruit juices are a natural source of sugars, there is a controversy whether their sugar content has similar harmful effects as beverages’ added-sugars. We aimed to study the role of fruit juice sugars in inducing overweight, hyperglycaemia, glycation and oxidative stress in normal and diabetic animal models. In diabetic Goto-Kakizaki (GK) rats, we compared the effects of four different fruit juices (4-weeks) with sugary solutions having a similar sugar profile and concentration. In vitro, the sugary solutions were more susceptible to AGE formation than fruit juices, also causing higher postprandial glycaemia and lower erythrocytes’ antioxidant capacity in vivo (single intake). In GK rats, ad libitum fruit juice consumption (4-weeks) did not change body weight, glycaemia, oxidative stress nor glycation. Consumption of a matched volume of sugary solutions aggravated fasting glycaemia but had a moderate impact on caloric intake and oxidative stress/glycation markers in tissues of diabetic rats. Ad libitum availability of the same sugary solutions impaired energy balance regulation, leading to higher caloric intake than ad libitum fruit juices and controls, as well as weight gain, fasting hyperglycaemia, insulin intolerance and impaired oxidative stress/glycation markers in several tissues. We demonstrated the distinct role of sugars naturally present in fruit juices and added sugars in energy balance regulation, impairing oxidative stress, glycation and glucose metabolism in an animal model of type 2 diabetes.

Plant Extracts Rich in Polyphenols as Potent Modulators in the Growth of Probiotic and Pathogenic Intestinal Microorganisms

Medicinal plants and their extracts contain substantial quantities of polyphenols. As metabolically active plant metabolites, polyphenols are food components with a wide range of biological activities. Given their poor absorbability in the digestive tract their activity toward the human host is typically mediated through interaction with intestinal microbes. As a result, polyphenols comprise a novel group of prebiotics. In this study, we tested the effect of five polyphenol-rich extracts from four medicinal herbs on the growth of probiotic and pathogenic microbes. The studied medicinal herbs were Gentiana asclepiadea L. (willow gentian), Hypericum perforatum L. (St. John's wort), Satureja montana L. (winter savory), and Achillea millefolium L. (yarrow). All these plants are traditionally used for the treatment of digestive problems. Extracts were prepared using safe solvent combinations. We tested the impact of addition of plant extracts on the growth of three probiotic lactobacilli and probiotic yeast Saccharomyces boulardii. The effect of addition of plant extracts to liquid media (concentration range 0.25–10 mg/mL) on the growth of probiotics, was tested in vitro. The antimicrobial activity of the extracts was tested against several opportunistic bacteria and yeast. St. John's wort, winter savory, and willow gentian extracts showed a stimulative effect on probiotic yeast growth, while the highest growth-stimulating effect was achieved when microwave-assisted yarrow extract was used in the concentration of 0.5 mg/mL. Under these conditions growth of S. boulardii was increased 130-fold. In addition, the yarrow extract stimulated the growth of Lactiplantibacillus plantarum 299v. The growth of two Lacticasibacillus rhamnosus strains was not stimulated by the addition of any extracts. Our results show that plant polyphenol-rich extracts can influence the growth of microorganisms that are typical members of the intestinal microbiota. For the first time we demonstrate that probiotic yeast growth can be stimulated by extracts of medicinal herbs, which when accompanied by suppression of Candida yeasts suggests a potential benefit of the treatment in diseases that are associated with fungal dysbiosis.

A flavonoid-rich Smilax china L. extract prevents obesity by upregulating the adiponectin-receptor/AMPK signalling pathway and modulating the gut microbiota in mice

The aim of this study was to investigate the effects of Smilax china L. flavonoid (SCF) on obesity and changes in gut microbiota high-fat/high-sucrose (HFHS)-fed mice. Male C57BL/6 mice fed either a normal-chow (NC) or a HFHS diet were treated with SCF for 12 weeks. The effect of SCF on the composition of gut microbiota was assessed by 16S rDNA sequencing. SCFA levels in the caecum were quantified by GC-MS. SCF supplementation alleviated the body weight gain, fat accumulation, serum lipid parameters, and hepatic steatosis and improved glucose homeostasis. SCF significantly increased plasma adiponectin level, adiponectin-receptor-gene (AdipoR1 and AdipoR2) expression in the liver, activated AMPKα, downregulated the expression of SREBP1-c, FAS, and ACCα, and upregulated the expression of PPARα, CPT-1α, and UCP-1. The anti-obesity effects of SCF might be through upregulation of adiponectin-receptor/AMPK signalling to improve lipid metabolism. SCF reversed HFHS-induced dysbiosis of gut microbiota and decreased SCFA production in the caecum, thus reducing energy absorption and leading to loss of body weight. Spearman's correlation analysis revealed significant correlations between obesity phenotypes, SCFA levels, and changes in gut microbiota. The results showed that SCF may be an effective dietary supplement that is useful for suppressing the development of obesity and associated disorders.

Prebiotic Effect of Berberine and Curcumin Is Associated with the Improvement of Obesity in Mice

Berberine and curcumin, used as food additives or food supplements, possess interesting anti-inflammatory and antioxidant properties. We tested the potential protective effect of both phytochemicals in genetically obese mice and we determined whether these effects can be related to the modulation of gut functions and microbiota. Ob/ob mice were fed a standard diet supplemented with or without 0.1% berberine and/or 0.3% curcumin for 4 weeks. By using targeted qPCR, we found that cecal content of Bifidobacterium spp. and Akkermansia spp. increased mainly upon berberine supplementation. Genes involved in innate immunity (Pla2g2a), mucus production (Muc2) and satietogenic peptide production (Gcg and Pyy) were upregulated in the colon of mice treated with both phytochemicals. Berberine supplementation alone reduced food intake, body weight gain, hypertriglyceridemia and hepatic inflammatory and oxidative stress markers, thus lessening hepatic injury. The increase in Bifidobacterium spp. and Akkermansia spp. was correlated with the improvement of gut barrier function and with the improvement of hepatic inflammatory and oxidative stresses in obese mice. These data support the fact that non-carbohydrate phytochemicals may modulate the gut microbiota in obesity and related gut and hepatic alterations.

In vitro gastrointestinal digestion and simulated colonic fermentation of pistachio nuts determine the bioaccessibility and biosynthesis of chronobiotics

Chronodisruption leads to obesity and other metabolic disorders that can be alleviated by food-derived potential chronobiotics, such as phytomelatonin (PMT), phenolic compounds (PCs) and dietary fiber rich pistachios. Pistachios with (PN + SC) or without (PN) the seed coat were investigated for their in vitro chronobiotic potential since they are one of the main reported PMT sources. Consequently we evaluated the bioaccessibility, permeability, and biosynthesis of pistachio chronobiotics, particularly PMT, during gastrointestinal and colonic fermentation. The maximum in vitro bioaccessibility and apparent permeability (efflux-prone) of PCs, flavonoids and PMT were sample-specific [∼1.3% (both), 27 and 3.4% (PN + SC)], but additional amounts (flavonoids > PCs > PMT) were released under simulated colonic conditions. Short-chain fatty acids (SCFAs; 38 mM; >50% butyrate, PN + SC > PN) and some metabolites (e.g., indole, benzaldehyde, phenolic acids, and aliphatic/aromatic hydrocarbons) were detected depending on the sample. The predominant pistachio butyrate production during in vitro colonic fermentation can improve chronodisruption and benefit obese individuals. Pistachio's digestion increases the bioaccessibility and intestinal permeability of potential chronobiotics (PMT and PCs) and the biosynthesis of colonic metabolites (SCFAs, among others) also with chronobiotic potential.

A Novel Grape-Derived Prebiotic Selectively Enhances Abundance and Metabolic Activity of Butyrate-Producing Bacteria in Faecal Samples

Inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) patients have different faecal microbiota profiles compared to healthy controls. Prebiotics intake influences intestinal microbiota composition which in turn influence the growth of short-chain fatty acids (SCFA) producing bacteria. This study aimed to evaluate the capacity of Previpect, a new prebiotic obtained from grapes fibre, to balance the dysbiosis found in patients with intestinal disorders. This was achieved through the analysis of specific bacterial markers and SCFA production using an in vitro fermentation system and comparing the obtained results with those obtained with other commercial prebiotics. Fresh faecal samples from patients with IBD (N = 6), IBS (N = 3), and control subjects (N = 6) were used. Previpect showed high fermentative ability enabling the growth of butyrate producing bacteria and increasing SCFA concentration up to 2.5-fold. Previpect is a promising prebiotic which may be used as a therapeutic strategy towards promotion of intestinal microbiota restoration, microbial healing, and as a preventive supplement for healthy individuals.

Effects of Clostridium butyricum on growth performance, metabonomics and intestinal microbial differences of weaned piglets

Background

Weaning stress of piglets causes a huge economic loss to the pig industry. Balance and stability of the intestinal microenvironment is an effective way to reduce the occurance of stress during the weaning process. Clostridium butyricum, as a new microecological preparation, is resistant to high temperature, acid, bile salts and some antibiotics. The aim of present study is to investigate the effects of C. butyricum on the intestinal microbiota and their metabolites in weaned piglets.

Results

There was no statistical significance in the growth performance and the incidence of diarrhoea among the weaned piglets treated with C. butyricum during 0–21 days experimental period. Analysis of 16S rRNA gene sequencing results showed that the operational taxonomic units (OTUs), abundance-based coverage estimator (ACE) and Chao index of the CB group were found to be significantly increased compared with the NC group (P < 0.05). Bacteroidetes, Firmicutes and Tenericutes were the predominant bacterial phyla in the weaned piglets. A marked increase in the relative abundance of Megasphaera, Ruminococcaceae_NK4A214_group and Prevotellaceae_UCG-003, along with a decreased relative abundance of Ruminococcaceae_UCG-005 was observed in the CB group, when compared with the NC group (P < 0.05). With the addition of C. butyricum, a total of twenty-two significantly altered metabolites were obtained in the feces of piglets. The integrated pathway analysis by MetaboAnalyst indicated that arginine and proline metabolism; valine, leucine and isoleucine biosynthesis; and phenylalanine metabolism were the main three altered pathways, based on the topology. Furthermore, Spearman’s analysis revealed some altered gut microbiota genus such as Oscillospira, Ruminococcaceae_NK4A214_group, Megasphaera, Ruminococcaceae_UCG-005, Prevotella_2, Ruminococcaceae_UCG-002, Rikenellaceae_RC9_gut_group and Prevotellaceae_UCG-003 were associated with the alterations in the fecal metabolites (P < 0.05), indicating that C. butyricum presented a potential protective impact through gut microbiota. The intestinal metabolites changed by C. butyricum mainly involved the variation of citrulline, dicarboxylic acids, branched-chain amino acid and tryptophan metabolic pathways.

Conclusions

Overall, this study strengthens the idea that the dietary C. butyricum treatment can significantly alter the intestinal microbiota and metabolite profiles of the weaned piglets, and C. butyricum can offer potential benefits for the gut health.

Carob fruit extract-enriched meat, as preventive and curative treatments, improves gut microbiota and colonic barrier integrity in a late-stage T2DM model

Epidemiological and experimental studies have suggested that dietary fiber and proanthocyanidins play an important role on gut microbiota (GM), colonic integrity and body health. Type 2 Diabetes Mellitus (T2DM) is a prevalent disease in which the modifications in the GM and colonic markers stand out. This manuscript hypothesizes the consumption of functional meat enriched in carob fruit extract [CFE; CFE-restructured meat (RM)] ameliorates the dysbiosis and colonic barrier integrity loss in a late-stage T2DM rat model induced by the conjoint action of a high-saturated-fat/high-cholesterol diet (Chol-diet) and a low dose of streptozotocin (STZ) plus a nicotinamide (NAD) injection. Three groups of eight rats were used: (1) D group, a T2DM control group, fed the Chol-diet; (2) ED group, a T2DM preventive strategy group fed the CFE-Chol-diet since the beginning of the study; and (3) DE group, a T2DM curative treatment group, fed the CFE-Chol-diet once the diabetic state was confirmed. The study lasted 8 weeks. Amount and variety of GM, feces short-chain-fatty acids (SCFAs), colonic morphology [crypt depth and density, goblet cells, proliferating cell nuclear antigen (PCNA) and transferase dUTP nick end labelling (TUNEL) indexes] and tight junctions were evaluated. A global colonic index combining 17 markers (GC_index) was calculated. ED rats displayed higher levels of GM richness, SCFAs production, crypt depth, and goblet cells than the D group. DE group showed lower Enterobacteriaceae abundance and greater TUNEL index and occludin expression in the distal colon than D counterpart. GC_index differentiated the colonic health status of the experimental groups in the order (ED > DE > D; P < 0.001) as a 17-51 range-quotation, ED, DE, and D groups displayed the values 43, 32.5, and 27, respectively. Thus, CFE-RM used as a T2DM preventive therapy could induce higher GM richness, more adequate SCFAs production, and better colonic barrier integrity. Furthermore, CFE-RM used with curative purposes induced more modest changes and mainly at the distal colonic mucosa. Further studies are needed to confirm this study's results, to ascertain the benefits of consuming proanthocyanidins-rich fiber during different T2DM stages.

Regulation of Enteric Infection and Immunity by Dietary Proanthocyanidins

The role of dietary components in immune function has acquired considerable attention in recent years. An important focus area is to unravel the role of bioactive dietary compounds in relation to enteric disease and their impact on gut mucosal immunity. Proanthocyanidins (PAC) are among the most common and most consumed dietary polyphenols, and are characterised by their variable molecular structures and diverse bioactivities. In particular, their anti-oxidative effects and ability to modulate gut microbiota have been widely described. However, there is limited evidence on the mechanism of action of PAC on the immune system, nor is it clearly established how PAC may influence susceptibility to enteric infections. Establishing the sites of action of PAC and their metabolites within the gut environment is fundamental to determine the applicability of PAC against enteric pathogens. Some mechanistic studies have shown that PAC have direct modulatory effects on immune cell signalling, isolated pathogens, and gut mucosal barrier integrity. Boosting the recruitment of immune cells and suppressing the amount of pro-inflammatory cytokines are modulating factors regulated by PAC, and can either be beneficial or detrimental in the course of re-establishing gut homeostasis. Herein, we review how PAC may alter distinct immune responses towards enteric bacterial, viral and parasitic infections, and how the modulation of gut microbiota may act as a mediating factor. Furthermore, we discuss how future studies could help unravel the role of PAC in preventing and/or alleviating intestinal inflammation and dysbiosis caused by enteric disease.

Efficacy of Polyphenols in the Management of Dyslipidemia: A Focus on Clinical Studies

Polyphenols (PLPs), phytochemicals found in a wide range of plant-based foods, have gained extensive attention in view of their antioxidant, anti-inflammatory, immunomodulatory and several additional beneficial activities. The health-promoting effects noted in animal models of various non-communicable diseases explain the growing interest in these molecules. In particular, in vitro and animal studies reported an attenuation of lipid disorders in response to PLPs. However, despite promising preclinical investigations, the effectiveness of PLPs in human dyslipidemia (DLP) is less clear and necessitates revision of available literature. Therefore, the present review analyzes the role of PLPs in managing clinical DLP, notably by dissecting their potential in ameliorating lipid/lipoprotein metabolism and alleviating hyperlipidemia, both postprandially and in long-term interventions. To this end, PubMed was used for article search. The search terms included polyphenols, lipids, triglycerides, cholesterol, LDL-cholesterol and /or HDL-cholesterol. The critical examination of the trials published to date illustrates certain benefits on blood lipids along with co-morbidities in participant’s health status. However, inconsistent results document significant research gaps, potentially owing to study heterogeneity and lack of rigor in establishing PLP bioavailability during supplementation. This underlines the need for further efforts in order to elucidate and support a potential role of PLPs in fighting DLP.

A Pilot Study for Metabolic Profiling of Obesity-Associated Microbial Gut Dysbiosis in Male Wistar Rats

Obesity is one of the most incident and concerning disease worldwide. Definite strategies to prevent obesity and related complications remain elusive. Among the risk factors of the onset of obesity, gut microbiota might play an important role in the pathogenesis of the disease, and it has received extensive attention because it affects the host metabolism. In this study, we aimed to define a metabolic profile of the segregated obesity-associated gut dysbiosis risk factor. The study of the metabolome, in an obesity-associated gut dysbiosis model, provides a relevant way for the discrimination on the different biomarkers in the obesity onset. Thus, we developed a model of this obesity risk factors through the transference of gut microbiota from obese to non-obese male Wistar rats and performed a subsequent metabolic analysis in the receptor rats. Our results showed alterations in the lipid metabolism in plasma and in the phenylalanine metabolism in urine. In consequence, we have identified metabolic changes characterized by: (1) an increase in DG:34:2 in plasma, a decrease in hippurate, (2) an increase in 3-HPPA, and (3) an increase in o-coumaric acid. Hereby, we propose these metabolites as a metabolic profile associated to a segregated dysbiosis state related to obesity disease.