A randomized controlled trial on the efficacy of resistant dextrin, as functional food, in women with type 2 diabetes: Targeting the hypothalamic-pituitary-adrenal axis and immune system

Human T-cell activation with Toxoplasma gondii antigens loaded in maltodextrin nanoparticles

Toxoplasmosis is the most prevalent parasitic zoonosis worldwide, causing ocular and neurological diseases. No vaccine has been approved for human use. We evaluated the response of peripheral blood mononuclear cells (PBMCs) to a novel construct of Toxoplasma gondii total antigen in maltodextrin nanoparticles (NP/TE) in individuals with varying infectious statuses (uninfected, chronic asymptomatic, or ocular toxoplasmosis). We analyzed the concentration of IFN-γ after NP/TE ex vivo stimulation using ELISA and the immunophenotypes of CD4+ and CD8+ cell populations using flow cytometry. In addition, serotyping of individuals with toxoplasmosis was performed by ELISA using GRA6-derived polypeptides. Low doses of NP/TE stimulation (0.9 μg NP/0.3 μg TE) achieved IFN-γ-specific production in previously exposed human PBMCs without significant differences in the infecting serotype. Increased IFN-γ expression in CD4+ effector memory cell subsets was found in patients with ocular toxoplasmosis with NP/TE but not with TE alone. This is the first study to show how T-cell subsets respond to ex vivo stimulation with a vaccine candidate for human toxoplasmosis, providing crucial insights for future clinical trials.

Increasing dietary fiber intake for type 2 diabetes mellitus management: A systematic review

BACKGROUND

Type 2 diabetes is a chronic, non-communicable disease with a substantial global impact, affecting a significant number of individuals. Its etiology is closely tied to imbalanced dietary practices and sedentary lifestyles. Conversely, increasing die-tary fiber (DF) intake has consistently demonstrated health benefits in numerous studies, including improvements in glycemic control and weight management.

AIM

To investigate the efficacy of DF interventions in the management of type 2 diabetes mellitus (T2DM).

METHODS

A systematic literature review was conducted to explore the association between DF intake and the management of T2DM. Following the inclusion and exclusion criteria, a total of 26 studies were included in this review.

RESULTS

The main strategies implied to increased DF intake were: High DF diet plus acarbose (2 studies); DF supplements (14 studies); and high DF diets (10 studies). Overall, most studies indicated that increased DF intake resulted in im-provements in glycemic control and weight management in T2DM patients.

CONCLUSION

DF represents a valuable strategy in the treatment of type 2 diabetes, improving health outcomes. DF intake offers the potential to improve quality of life and reduce complications and mortality associated with diabetes. Likewise, through supplements or enriched foods, DF contributes significantly to the control of several markers such as HbA1c, blood glucose, triglycerides, low-density lipoprotein, and body weight.

Polysaccharide-dextrin thickened fluids for individuals with dysphagia: recent advances in flow behaviors and swallowing assessment methods

The global aging population has brought about a pressing health concern: dysphagia. To effectively address this issue, we must develop specialized diets, such as thickened fluids made with polysaccharide-dextrin (e.g., water, milk, juices, and soups), which are crucial for managing swallowing-related problems like aspiration and choking for people with dysphagia. Understanding the flow behaviors of these thickened fluids is paramount, and it enables us to establish methods for evaluating their suitability for individuals with dysphagia. This review focuses on the shear and extensional flow properties (e.g., viscosity, yield stress, and viscoelasticity) and tribology (e.g., coefficient of friction) of polysaccharide-dextrin-based thickened fluids and highlights how dextrin inclusion influences fluid flow behaviors considering molecular interactions and chain dynamics. The flow behaviors can be integrated into the development of diverse evaluation methods that assess aspects such as flow velocity, risk of aspiration, and remaining fluid volume. In this context, the key in-vivo (e.g., clinical examination and animal model), in-vitro (e.g., the Cambridge Throat), and in-silico (e.g., Hamiltonian moving particles semi-implicit) evaluation methods are summarized. In addition, we explore the potential for establishing realistic assessment methods to evaluate the swallowing performance of thickened fluids, offering promising prospects for the future.

Integrated Analysis of Gut Microbiome and Adipose Transcriptome Reveals Beneficial Effects of Resistant Dextrin from Wheat Starch on Insulin Resistance in Kunming Mice

Systemic chronic inflammation is recognized as a significant contributor to the development of obesity-related insulin resistance. Previous studies have revealed the physiological benefits of resistant dextrin (RD), including obesity reduction, lower fasting glucose levels, and anti-inflammation. The present study investigated the effects of RD intervention on insulin resistance (IR) in Kunming mice, expounding the mechanisms through the gut microbiome and transcriptome of white adipose. In this eight-week study, we investigated changes in tissue weight, glucose-lipid metabolism levels, serum inflammation levels, and lesions of epididymal white adipose tissue (eWAT) evaluated via Hematoxylin and Eosin (H&E) staining. Moreover, we analyzed the gut microbiota composition and transcriptome of eWAT to assess the potential protective effects of RD intervention. Compared with a high-fat, high-sugar diet (HFHSD) group, the RD intervention significantly enhanced glucose homeostasis (e.g., AUC-OGTT, HOMA-IR, p < 0.001), and reduced lipid metabolism (e.g., TG, LDL-C, p < 0.001) and serum inflammation levels (e.g., IL-1β, IL-6, p < 0.001). The RD intervention also led to changes in the gut microbiota composition, with an increase in the abundance of probiotics (e.g., Parabacteroides, Faecalibaculum, and Muribaculum, p < 0.05) and a decrease in harmful bacteria (Colidextribacter, p < 0.05). Moreover, the RD intervention had a noticeable effect on the gene transcription profile of eWAT, and KEGG enrichment analysis revealed that differential genes were enriched in PI3K/AKT, AMPK, in glucose-lipid metabolism, and in the regulation of lipolysis in adipocytes signaling pathways. The findings demonstrated that RD not only ameliorated IR, but also remodeled the gut microbiota and modified the transcriptome profile of eWAT.

Characterization, health benefits, and food applications of enzymatic digestion- resistant dextrin: A review

Resistant dextrin or resistant maltodextrin (RD), a short-chain glucose polymer that is highly resistant to hydrolysis by human digestive enzymes, has shown broad developmental prospects in the food industry and has gained substantial attention owing to its lack of undesirable effects on the sensory features of food or the digestive system. However, comprehensive fundamental and application information on RD and how RD improves anti-diabetes and obesity have not yet been received. Therefore, the characterization, health benefits and application of RD in various fields are summarized and discussed in the current study. Typically, RD is prepared by the acid thermal method and possesses excellent physicochemical properties, including low viscosity, high solubility, storage stability, and low retro-gradation, which are correlated with its low molecular weight (Mw) and non-digestible glycosidic linkages. In contrast, RD prepared by the simultaneous debranching and crystallization method has low solubility and high crystallinity. The ingestion of RD can positively affect metabolic diseases (diabetes and obesity) in animals and humans by producing short-chain fatty acids (SCFAs), and facilitating the inflammatory response. Moreover, RD has been widely used in the beverage, dairy products, and dessert industries due to its nutritional value and textural properties without unacceptable quality loss. More studies are required to further explore RD application potential in the food industry and its role in the management of different chronic metabolic disorders.

Fiber intake and fiber intervention in depression and anxiety: a systematic review and meta-analysis of observational studies and randomized controlled trials

CONTEXT

Dietary fibers hold potential to influence depressive and anxiety outcomes by modulating the microbiota-gut-brain axis, which is increasingly recognized as an underlying factor in mental health maintenance.

OBJECTIVE

Evidence for the effects of fibers on depressive and anxiety outcomes remains unclear. To this end, a systematic literature review and a meta-analysis were conducted that included observational studies and randomized controlled trials (RCTs).

DATA SOURCES

The PubMed, Embase, CENTRAL, CINAHL, and PsychINFO databases were searched for eligible studies.

DATA EXTRACTION

Study screening and risk-of-bias assessment were conducted by 2 independent reviewers.

DATA ANALYSIS

Meta-analyses via random effects models were performed to examine the (1) association between fiber intake and depressive and anxiety outcomes in observational studies, and (2) effect of fiber intervention on depressive and anxiety outcomes compared with placebo in RCTs. A total of 181 405 participants were included in 23 observational studies. In cross-sectional studies, an inverse association was observed between fiber intake and depressive (Cohen's d effect size [d]: -0.11; 95% confidence interval [CI]: -0.16, -0.05) and anxiety (d = -0.25; 95%CI, -0.38, -0.12) outcomes. In longitudinal studies, there was an inverse association between fiber intake and depressive outcomes (d = -0.07; 95%CI, -0.11, -0.04). In total, 740 participants were included in 10 RCTs, all of whom used fiber supplements. Of note, only 1 RCT included individuals with a clinical diagnosis of depression. No difference was found between fiber supplementation and placebo for depressive (d = -0.47; 95%CI, -1.26, 0.31) or anxiety (d = -0.30; 95%CI, -0.67, 0.07) outcomes.

CONCLUSION

Although observational data suggest a potential benefit for higher fiber intake for depressive and anxiety outcomes, evidence from current RCTs does not support fiber supplementation for improving depressive or anxiety outcomes. More research, including RCTs in clinical populations and using a broad range of fibers, is needed.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42021274898.

[The Therapeutic Potential of Prebiotics and Probiotics in Child and Adolescent Psychiatric Disorders]

The Therapeutic Potential of Prebiotics and Probiotics in Child and Adolescent Psychiatric Disorders Abstract: This short review summarizes the literature available on therapeutic interventions with prebiotics and probiotics and their potential use in psychiatric disorders in childhood, adolescence, and adulthood. Most studies of children and adolescents are done on ADHD and autism spectrum disorders, whereas single reports exist largely on positive effects on cognitive symptoms and quality of life. Initial studies regarding anorexia nervosa point to a potential effect of weight gain and reduction of gastrointestinal symptoms. To date, the effects of prebiotics and probiotics in depression, bipolar disorder, anxiety disorders, and schizophrenia have been mainly investigated in adults. The best reported evidence exists for depression, whereas the effects on depressive symptomatology are small. Positive effects are seen on gastrointestinal symptoms in these disorders. Given these positive effects, the mixed literature reports may result from very heterogeneous study designs. Nevertheless, the high potential of prebiotics and probiotics may be seen for minors with mental health problems. Further studies that include child and adolescent psychiatric populations and reflect the complexity of the gut-brain axis are urgently needed.

Abnormal tryptophan catabolism in diabetes mellitus and its complications: Opportunities and challenges

In recent years, the incidence rate of diabetes mellitus (DM), including type 1 diabetes mellitus(T1DM), type 2 diabetes mellitus(T2DM), and gestational diabetes mellitus (GDM), has increased year by year and has become a major global health problem. DM can lead to serious complications of macrovascular and microvascular. Tryptophan (Trp) is an essential amino acid for the human body. Trp is metabolized in the body through the indole pathway, kynurenine (Kyn) pathway and serotonin (5-HT) pathway, and is regulated by intestinal microorganisms to varying degrees. These three metabolic pathways have extensive regulatory effects on the immune, endocrine, neural, and energy metabolism systems of the body, and are related to the physiological and pathological processes of various diseases. The key enzymes and metabolites in the Trp metabolic pathway are also deeply involved in the pathogenesis of DM, playing an important role in pancreatic function, insulin resistance (IR), intestinal barrier, and angiogenesis. In DM and its complications, there is a disruption of Trp metabolic balance. Several therapy approaches for DM and complications have been proven to modify tryptophan metabolism. The metabolism of Trp is becoming a new area of focus for DM prevention and care. This paper reviews the impact of the three metabolic pathways of Trp on the pathogenesis of DM and the alterations in Trp metabolism in these diseases, expecting to provide entry points for the treatment of DM and its complications.

Ex Vivo Colonic Fermentation of NUTRIOSE® Exerts Immuno-Modulatory Properties and Strong Anti-Inflammatory Effects

NUTRIOSE® (Roquette, Lestrem, France) is a resistant dextrin with well-established prebiotic effects. This study evaluated the indirect effects of pre-digested NUTRIOSE® on host immune response and gut barrier integrity. Fecal samples from eight healthy donors were inoculated in a Colon-on-a-plate® system (ProDigest, Ghent, Belgium) with or without NUTRIOSE® supplementation. Following 48 h fermentation, colonic suspensions were tested in a Caco-2/THP1-Blue™ co-culture system to determine their effects on gut barrier activity (transepithelial electrical resistance) and immune response following lipopolysaccharide stimulation. Additionally, changes in short-chain fatty acid levels (SCFA) and microbial community composition following a 48 h fermentation in the Colon-on-a-plate® system were measured. Across all donors, immune-mediated intestinal barrier damage was significantly reduced with NUTRIOSE®-supplemented colonic suspensions versus blank. Additionally, IL-6 and IL-10 levels were significantly increased, and the level of the neutrophil chemoattractant IL-8 was significantly decreased with NUTRIOSE®-supplemented colonic suspensions versus blank in the co-culture models following lipopolysaccharide stimulation. These beneficial effects of NUTRIOSE® supplementation were likely due to increased acetate and propionate levels and the enrichment of SCFA-producing bacteria. NUTRIOSE® was well fermented by the colonic bacteria of all eight donors and had protective effects on inflammation-induced disruption of the intestinal epithelial barrier and strong anti-inflammatory effects.

Microbiota-accessible carbohydrates (MACs) as novel gut microbiome modulators in noncommunicable diseases

The gut microbiota has a significant role in human health and is affected by many factors. Diet and dietary components have profound impacts on the composition of the gut microbiome and largely contribute to the change in bacterial flora. A high-fiber diet increased dietary fiber (DF) fermentation and the production of short-chain fatty acids (SCFAs), which increased the number of microorganisms. Microbiota-accessible carbohydrates (MACs), a subgroup of fermentable carbohydrates such as DF, are defined as indigestible carbohydrates metabolized by microbes. These carbohydrates are important components to sustain the microbial environment of the complicated digestive tract and avoid intestinal dysbiosis. Each MAC has a unique property and can therefore be used as a sensitive output microbiota modulator to support host homeostasis and modulate health. In addition to the overall health-developing effects, MACs are thought to have a promising effect on the prevention of non-communicable diseases (NCDs), which are major health problems worldwide. The aim of the manuscript was to describe microbiota-accessible carbohydrates and summarize their effects on gut modulation and NCDs.

Effects of a high-prebiotic diet versus probiotic supplements versus synbiotics on adult mental health: The "Gut Feelings" randomised controlled trial

Background

Preliminary evidence supports the use of dietary interventions and gut microbiota-targeted interventions such as probiotic or prebiotic supplementation for improving mental health. We report on the first randomised controlled trial (RCT) to examine the effects of a high-prebiotic dietary intervention and probiotic supplements on mental health.

Methods

"Gut Feelings" was an 8-week, 2 × 2 factorial RCT of 119 adults with moderate psychological distress and low prebiotic food intake. Treatment arms: (1) probiotic supplement and diet-as-usual (probiotic group); (2) high-prebiotic diet and placebo supplement (prebiotic diet group); (3) probiotic supplement and high-prebiotic diet (synbiotic group); and (4) placebo supplement and diet-as-usual (placebo group). The primary outcome was assessment of total mood disturbance (TMD; Profile of Mood States Short Form) from baseline to 8 weeks. Secondary outcomes included anxiety, depression, stress, sleep, and wellbeing measures.

Results

A modified intention-to-treat analysis using linear mixed effects models revealed that the prebiotic diet reduced TMD relative to placebo at 8 weeks [Cohen's d = -0.60, 95% confidence interval (CI) = -1.18, -0.03; p = 0.039]. There was no evidence of symptom improvement from the probiotic (d = -0.19, 95% CI = -0.75, 0.38; p = 0.51) or synbiotic treatments (d = -0.03, 95% CI = -0.59, 0.53; p = 0.92). Improved anxiety, stress, and sleep were noted in response to the prebiotic diet while the probiotic tentatively improved wellbeing, relative to placebo. No benefit was found in response to the synbiotic intervention. All treatments were well tolerated with few adverse events.

Conclusion

A high-prebiotic dietary intervention may improve mood, anxiety, stress, and sleep in adults with moderate psychological distress and low prebiotic intake. A synbiotic combination of high-prebiotic diet and probiotic supplement does not appear to have a beneficial effect on mental health outcomes, though further evidence is required. Results are limited by the relatively small sample size.

Clinical trial registration

https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=372753, identifier ACTRN12617000795392.

Potential of gut microbiota for lipopolysaccharide biosynthesis in European women with type 2 diabetes based on metagenome

The abnormal accumulation of lipopolysaccharide (LPS) plays a crucial role in promoting type 2 diabetes (T2D). However, the capability of the gut microbiota to produce LPS in patients with T2D is still unclear, and evidence characterizing the patterns of gut microbiota with LPS productivity remains rare. This study aimed to uncover the profiles of LPS-biosynthesis-related enzymes and pathways, and explore the potential of LPS-producing gut microbiota in T2D. The gut metagenomic sequencing data from a European female cohort with normal glucose tolerance or untreated T2D were analyzed in this study. The sequence search revealed that the relative abundance of the critical enzymes responsible for LPS biosynthesis was significantly high in patients with T2D, especially for N-acetylglucosamine deacetylase, 3-deoxy-D-manno-octulosonic-acid transferase, and lauroyl-Kdo2-lipid IVA myristoyltransferase. The functional analysis indicated that a majority of pathways involved in LPS biosynthesis were augmented in patients with T2D. A total of 1,173 species from 335 genera containing the gene sequences of LPS enzymes, including LpxA/B/C/D/H/K/L/M and/or WaaA, coexisted in controls and patients with T2D. Critical taxonomies with discriminative fecal abundance between groups were revealed, which exhibited different associations with enzymes. Moreover, the identified gut microbial markers had correlations with LPS enzymes and were subsequently associated with microbial pathways. The present findings delineated the potential capability of gut microbiota toward LPS biosynthesis in European women and highlighted a gut microbiota−based mechanistic link between the disturbance in LPS biosynthesis and T2D. The restoration of LPS levels through gut microbiota manipulation might offer potential approaches for preventing and treating T2D.

Short-Clustered Maltodextrin Activates Ileal Glucose-Sensing and Induces Glucagon-like Peptide 1 Secretion to Ameliorate Glucose Homeostasis in Type 2 Diabetic Mice

Reconstructing molecular structure is an effective approach to attenuating glycemic response to starch. Previously, we rearranged α-1,4 and α-1,6-glycosidic bonds in starch molecules to produce short-clustered maltodextrin (SCMD). The present study revealed that SCMD slowly released glucose until the distal ileum. The activated ileal glucose-sensing enabled SCMD to be a potent inducer for glucagon-like peptide-1 (GLP-1). Furthermore, SCMD was found feasible to serve as the dominant dietary carbohydrate to rescue mice from diabetes. Interestingly, a mixture of normal maltodextrin and resistant dextrin (MD+RD), although it caused an attenuated glycemic response similar to that of SCMD, failed to ameliorate glucose homeostasis because it hardly induced GLP-1 secretion. The serum GLP-1 levels seen in MD+RD-fed mice (5.25 ± 1.51 pmol/L) were significantly lower than those seen in SCMD-fed mice (8.25 ± 2.01 pmol/L, p < 0.05). Further investigation revealed that the beneficial effects of SCMD could be abolished by a GLP-1 receptor (GLP-1R) antagonist. These results identify GLP-1R signaling as a critical contributor to SCMD-exerted health benefits and highlight the role of ileal glucose-sensing in designing dietary carbohydrates.

Effects of inulin supplementation on inflammatory biomarkers and clinical symptoms of women with obesity and depression on a calorie-restricted diet: a randomised controlled clinical trial

Major depressive disorder (MDD) is regarded as an inflammatory disorder. Gut microbiota dysbiosis, observed in both MDD and obesity, leads to endotoxemia and inflammatory status, eventually exacerbating depressive symptoms. Manipulation of gut microbiota by prebiotics might help alleviate depression. The present study aimed to investigate the effects of inulin supplementation on psychological outcomes and biomarkers of gut permeability, endotoxemia, inflammation, and brain-derived neurotrophic factor (BDNF) in women with obesity and depression on a calorie-restricted diet. In a double-blind randomised clinical trial, forty-five women with obesity and MDD were allocated to receive 10 g/d of either inulin or maltodextrin for 8 weeks; all the patients followed a healthy calorie restricted diet as well. Anthropometric measures, dietary intakes, depression, and serum levels of zonulin, lipopolysaccharide (LPS), inflammatory biomarkers (TNF-α, IL-10, monocyte chemoattractant protein-1, toll-like receptor-4 and high-sensitivity C-reactive protein), and BDNF were assessed at baseline and end of the study. Weight and Hamilton Depression Rating Scale (HDRS) scores decreased in both groups; between-group differences were non-significant by the end of study (P = 0·333 for body weight and P = 0·500 for HDRS). No between-group differences were observed for the other psychological outcomes and serum biomarkers (P > 0·05). In this short-term study, prebiotic supplementation had no significant beneficial effects on depressive symptoms, gut permeability, or inflammatory biomarkers in women with obesity and depression.

Improvement of sleep by resistant dextrin prebiotic in type 2 diabetic women coincides with attenuation of metabolic endotoxemia: involvement of gut-brain axis

BACKGROUND

Resistant dextrin, as a prebiotic and functional food, may possess favorable effects in type 2 diabetes. This study was conducted to assess whether supplementation with resistant dextrin can improve sleep and quality of life in obese type 2 diabetic women.

RESULTS

In this randomized controlled trial, female obese type 2 diabetic patients (n = 76) were randomly assigned into intervention group (n = 38) and placebo group (n = 38), and received 10 g day^-1 of resistant dextrin or maltodextrin for a period of 8 weeks, respectively. Sleep quality and quality of life (QOL) were assessed by Pittsburgh Sleep Quality Index (PSQI) and SF-36 health survey, respectively. Fasting blood samples were driven to measure serum bacterial endotoxin, fasting blood sugar, glycosylated hemoglobin (HbA1c), pro-inflammatory/anti-inflammatory biomarkers (IL-18, IL-6, IL-10, TNF-α), and biomarkers of hypothalamic-pituitary-adrenal (HPA) axis function [tryptophan (TRP), adrenocorticotropic hormone (ACTH), kynurenine (KYN), cortisol]. Supplementation with resistant dextrin improved sleep (P < 0.001) and QOL (P < 0.001) significantly. It also caused a significant decrease in levels of endotoxin, HbA1c, IL-18, IL-6, TNF-α and a significant increase in IL-10 levels. Significant and positive correlations were found between endotoxin (r = 0.488, P = 0.003), IL-6 (r = 0.436, P = 0.008), IL-18 (r = 0.475, P = 0.003), cortisol (r = 0.545, P = 0.048), KYN/TRP (r = 0.527, P = 0.001), and PSQI scores.

CONCLUSIONS

It is concluded that resistant dextrin improves sleep and QOL in obese women with type 2 diabetes. Its beneficial effects may be attributed in part to modulation of glycemia, metabolic endotoxemia and subsequently a decrease in biomarkers of inflammation and HPA axis activity. © 2022 Society of Chemical Industry.

Microbial-derived metabolites as a risk factor of age-related cognitive decline and dementia

A consequence of our progressively ageing global population is the increasing prevalence of worldwide age-related cognitive decline and dementia. In the absence of effective therapeutic interventions, identifying risk factors associated with cognitive decline becomes increasingly vital. Novel perspectives suggest that a dynamic bidirectional communication system between the gut, its microbiome, and the central nervous system, commonly referred to as the microbiota-gut-brain axis, may be a contributing factor for cognitive health and disease. However, the exact mechanisms remain undefined. Microbial-derived metabolites produced in the gut can cross the intestinal epithelial barrier, enter systemic circulation and trigger physiological responses both directly and indirectly affecting the central nervous system and its functions. Dysregulation of this system (i.e., dysbiosis) can modulate cytotoxic metabolite production, promote neuroinflammation and negatively impact cognition. In this review, we explore critical connections between microbial-derived metabolites (secondary bile acids, trimethylamine-N-oxide (TMAO), tryptophan derivatives and others) and their influence upon cognitive function and neurodegenerative disorders, with a particular interest in their less-explored role as risk factors of cognitive decline.

Diet Supplementation with NUTRIOSE, a Resistant Dextrin, Increases the Abundance of Parabacteroides distasonis in the Human Gut

SCOPE

An imbalance of the gut microbiota ("dysbiosis") is associated with numerous chronic diseases, and its modulation is a promising novel therapeutic approach. Dietary supplementation with soluble fiber is one of several proposed modulation strategies. This study aims at confirming the impact of the resistant dextrin NUTRIOSE (RD), a soluble fiber with demonstrated beneficial health effects, on the gut microbiota of healthy individuals.

METHODS AND RESULTS

Fifty healthy women are enrolled and supplemented daily with either RD (n = 24) or a control product (n = 26) during 6 weeks. Characterization of the fecal metagenome with shotgun sequencing reveals that RD intake dramatically increases the abundance of the commensal bacterium Parabacteroides distasonis. Furthermore, presence in metagenomes of accessory genes from P. distasonis, coding for susCD (a starch-binding membrane protein complex) is associated with a greater increase of the species. This suggests that response to RD might be strain-dependent.

CONCLUSION

Supplementation with RD can be used to specifically increase P. distasonis in gut microbiota of healthy women. The magnitude of the response may be associated with fiber-metabolizing capabilities of strains carried by subjects. Further research will seek to confirm that P. distasonis directly modulates the clinical effects observed in other studies.

The Promising Role of Microbiome Therapy on Biomarkers of Inflammation and Oxidative Stress in Type 2 Diabetes: A Systematic and Narrative Review

Background

One in 10 adults suffer from type 2 diabetes (T2D). The role of the gut microbiome, its homeostasis, and dysbiosis has been investigated with success in the pathogenesis as well as treatment of T2D. There is an increasing volume of literature reporting interventions of pro-, pre-, and synbiotics on T2D patients.

Methods

Studies investigating the effect of pro-, pre-, and synbiotics on biomarkers of inflammation and oxidative stress in T2D populations were extracted from databases such as PubMed, Scopus, Web of Science, Embase, and Cochrane from inception to January 2022.

Results

From an initial screening of 5,984 hits, 47 clinical studies were included. Both statistically significant and non-significant results have been compiled, analyzed, and discussed. We have found various promising pro-, pre-, and synbiotic formulations. Of these, multistrain/multispecies probiotics are found to be more effective than monostrain interventions. Additionally, our findings show resistant dextrin to be the most promising prebiotic, followed closely by inulin and oligosaccharides. Finally, we report that synbiotics have shown excellent effect on markers of oxidative stress and antioxidant enzymes. We further discuss the role of metabolites in the resulting effects in biomarkers and ultimately pathogenesis of T2D, bring attention toward the ability of such nutraceuticals to have significant role in COVID-19 therapy, and finally discuss few ongoing clinical trials and prospects.

Conclusion

Current literature of pro-, pre- and synbiotic administration for T2D therapy is promising and shows many significant results with respect to most markers of inflammation and oxidative stress.

Effect of the Consumption of Alcohol-Free Beers with Different Carbohydrate Composition on Postprandial Metabolic Response

Background: We investigated the postprandial effects of an alcohol-free beer with modified carbohydrate (CH) composition compared to regular alcohol-free beer. Methods: Two randomized crossover studies were conducted. In the first study, 10 healthy volunteers received 25 g of CH in four different periods, coming from regular alcohol-free beer (RB), alcohol-free beer enriched with isomaltulose and a resistant maltodextrin (IMB), alcohol-free beer enriched with resistant maltodextrin (MB), and a glucose-based beverage. In the second study, 20 healthy volunteers were provided with 50 g of CH from white bread (WB) plus water, or with 14.3 g of CH coming from RB, IMB, MB, and extra WB. Blood was sampled after ingestion every 15 min for 2 h. Glucose, insulin, incretin hormones, TG, and NEFAs were determined in all samples. Results: The increase in glucose, insulin, and incretin hormones after the consumption of IMB and MB was significantly lower than after RB. The consumption of WB with IMB and MB showed significantly less increase in glucose levels than WB with water or WB with RB. Conclusions: The consumption of an alcohol-free beer with modified CH composition led to a better postprandial response compared to a conventional alcohol-free beer.

The Effects of Prebiotics, Synbiotics, and Short-Chain Fatty Acids on Respiratory Tract Infections and Immune Function: A Systematic Review and Meta-Analysis

Prebiotics, synbiotics, and SCFAs have been shown to decrease systemic inflammation and play a protective role in chronic respiratory conditions. However, their effects on infection and immune function are unclear. The objective of this systematic review was to summarize the current evidence for prebiotic, synbiotic, and SCFA supplementation on respiratory tract infections (RTIs) and immune function. The protocol for this systematic review was registered with PROSPERO (National Institute for Health Research, University of York, UK), accessed online at https://www.crd.york.ac.uk/prospero (CRD42019118786). Relevant English-language articles up to May 2021 were identified via online databases: MEDLINE, EMBASE, CINAHL, and Cochrane Library. Included studies (n = 58) examined the effect of prebiotics, synbiotics, or SCFA, delivered orally, on the incidence, severity, or duration of RTIs and/or markers of immune function (e.g., peripheral blood immunophenotyping, NK cell activity). The majority of studies were randomized controlled trials reporting on RTIs in infants and children. The meta-analysis indicated that the numbers of subjects with ≥1 RTI were reduced with prebiotic (OR, 0.73; 95% CI: 0.62-0.86; P = 0.0002; n = 17) and synbiotic (OR, 0.75; 95% CI: 0.65-0.87; P = 0.0001; n = 9) supplementation compared to placebo. Further, NK cell activity was increased with synbiotic (standardized mean difference, 0.74; 95% CI: 0.42-1.06; P < 0.0001, n = 3) supplementation. This review provides evidence that prebiotic, specifically oligosaccharide, supplementation may play a protective role in RTIs in infants and children. There is less evidence for this effect in adults. Supplementation with prebiotic and synbiotic treatment may alter immune function by increasing NK cell activity, though effects on immunophenotype were less clear.

Efficiency of Resistant Starch and Dextrins as Prebiotics: A Review of the Existing Evidence and Clinical Trials

In well-developed countries, people have started to pay additional attention to preserving healthy dietary habits, as it has become common knowledge that neglecting them may easily lead to severe health impairments, namely obesity, malnutrition, several cardiovascular diseases, type-2 diabetes, cancers, hypertensions, and inflammations. Various types of functional foods were developed that are enriched with vitamins, probiotics, prebiotics, and dietary fibers in order to develop a healthy balanced diet and to improve the general health of consumers. Numerous kinds of fiber are easily found in nature, but they often have a noticeable undesired impact on the sensory features of foods or on the digestive system. This led to development of modified dietary fibers, which have little to no impact on taste of foods they are added to. At the same time, they possess all the benefits similar to those of prebiotics, such as regulating gastrointestinal microbiota composition, increasing satiety, and improving the metabolic parameters of a human. In the following review, the evidence supporting prebiotic properties of modified starches, particularly resistant starches and their derivatives, resistant dextrins, was assessed and deliberated, which allowed drawing an interesting conclusion on the subject.

Potential Dietary Interventions for COVID-19 Infection Based on the Gut-Immune Axis: An Update Review on Bioactive Component of Macronutrients

Recently emerged coronavirus, known as SARS-CoV-2 or Covid-19 is considered as a serious threat for human health. Due to unavailable specific drugs for this virus, there is an urgent need for supportive cares. Epigenetic immune boosting approaches and developing anti-inflammatory agents by gut-associated bioactive macronutrients can be plausible protective cares for COVID-19. Suitable intake of bioactive macronutrients including prebiotics, fatty acids, proteins and branched-chain amino acids may result in anti-viral responses through modulating macrophages and dendritic cells via Toll-like receptors, decreasing viral load, inactivating the enveloped viruses, increasing the anti-inflammatory metabolites and inhibiting the proliferation of microbial organisms. Bioactive macronutrients may help in promotion of immunological responses and recovery acceleration against Covid-19. This review focuses on the mechanisms of bioactive macronutrients and related clinical trials on enveloped viruses with emphasis on gut-microbiome-immune axis. Macronutrients and this axis may be conducive strategies to protect host against the viral infection.

Co-supplementation of camelina oil and a prebiotic is more effective for in improving cardiometabolic risk factors and mental health in patients with NAFLD: a randomized clinical trial

This trial evaluated the effects of co-supplementing Camelina sativa oil (CSO) and a prebiotic as modulators of the gut microbiota on cardiometabolic risk factors and mental health in NAFLD patients. In all, 44 subjects with NAFLD were allocated to either an intervention (20 g d-1 CSO + resistant dextrin) or a placebo (20 g d-1 CSO + maltodextrin) group and received a calorie-restricted diet (-500 kcal d-1) for 12 weeks. Fasting plasma levels of gucose, insulin, hs-CRP, endotoxin, antioxidant enzyme activity, total antioxidant capacity (TAC), malondialdehyde (MDA), 8-iso-prostaglandin F2α, and uric acid were measured at the baseline and post-intervention. The depression, anxiety and stress scale (DASS) and the general health questionnaire (GHQ) were used to assess mental health. Co-supplementing CSO and resistant dextrin significantly decreased the level of insulin concentration (-0.84 μU ml-1, p = 0.011), HOMA-IR (-0.27, p = 0.021), hs-CRP (-1.25 pg ml-1, p = 0.023), endotoxin (-3.70 EU mL-1, p = 0.001), cortisol (-2.43, p = 0.033), GHQ (-5.03, p = 0.035), DASS (-9.01, p = 0.024), and MDA (-0.54 nmol mL-1, p = 0.021) and increased the levels of TAC (0.16 mmol L-1, p = 0.032) and superoxide dismutase (106.32 U g-1 Hb, p = 0.45) in the intervention group compared with the placebo group. No significant changes were observed in the levels of other biomarkers. Co-supplementing CSO and resistant dextrin in combination with a low-calorie diet may improve metabolic risk factors and mental health in NAFLD patients.

Diet and the Microbiota-Gut-Brain Axis: Sowing the Seeds of Good Mental Health

Over the past decade, the gut microbiota has emerged as a key component in regulating brain processes and behavior. Diet is one of the major factors involved in shaping the gut microbiota composition across the lifespan. However, whether and how diet can affect the brain via its effects on the microbiota is only now beginning to receive attention. Several mechanisms for gut-to-brain communication have been identified, including microbial metabolites, immune, neuronal, and metabolic pathways, some of which could be prone to dietary modulation. Animal studies investigating the potential of nutritional interventions on the microbiota-gut-brain axis have led to advancements in our understanding of the role of diet in this bidirectional communication. In this review, we summarize the current state of the literature triangulating diet, microbiota, and host behavior/brain processes and discuss potential underlying mechanisms. Additionally, determinants of the responsiveness to a dietary intervention and evidence for the microbiota as an underlying modulator of the effect of diet on brain health are outlined. In particular, we emphasize the understudied use of whole-dietary approaches in this endeavor and the need for greater evidence from clinical populations. While promising results are reported, additional data, specifically from clinical cohorts, are required to provide evidence-based recommendations for the development of microbiota-targeted, whole-dietary strategies to improve brain and mental health.

Gutted! Unraveling the Role of the Microbiome in Major Depressive Disorder

Microorganisms can be found in virtually any environment. In humans, the largest collection of microorganisms is found in the gut ecosystem. The adult gut microbiome consists of more genes than its human host and typically spans more than 60 genera from across the taxonomic tree. In addition, the gut contains the largest number of neurons in the body, after the brain. In recent years, it has become clear that the gut microbiome is in communication with the brain, through the gut-brain axis. A growing body of literature shows that the gut microbiome plays a shaping role in a variety of psychiatric disorders, including major depressive disorder (MDD). In this review, the interplay between the microbiome and MDD is discussed in three facets. First, we discuss factors that affect the onset/development of MDD that also greatly impinge on the composition of the gut microbiota-especially diet and stressful life events. We then examine the interplay between the microbiota and MDD. We examine evidence suggesting that the microbiota is altered in MDD, and we discuss why the microbiota should be considered during MDD treatment. Finally, we look toward the future and examine how the microbiota might become a therapeutic target for MDD. This review is intended to introduce those familiar with the neurological and psychiatric aspects of MDD to the microbiome and its potential role in the disorder. Although research is in its very early days, with much yet to be the understood, the microbiome is offering new avenues for developing potentially novel strategies for managing MDD.

Higher intake of microbiota-accessible carbohydrates and improved cardiometabolic risk factors: a meta-analysis and umbrella review of dietary management in patients with type 2 diabetes

BACKGROUND

Microbiota-accessible carbohydrates (MACs) are critical substrates for intestinal microbes; the subsequent production of SCFAs may have some potential benefits for patients with type 2 diabetes mellitus (T2DM).

OBJECTIVES

We conducted a meta-analysis of randomized controlled trials (RCTs) to assess the effects of higher compared with lower MAC intakes on cardiovascular risk factors in T2DM patients and performed an umbrella review of RCTs to evaluate the evidence quality concerning existing dietary T2DM interventions.

METHODS

Publications were identified by searching MEDLINE, EMBASE, and CINAHL. In the meta-analysis, random-effects models were used to calculate pooled estimates, and sensitivity analyses, meta-regression, subgroup analyses, and Egger's test were performed. For the umbrella review, we summarized pooled estimates, 95% CIs, heterogeneity, and publication bias. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) and modified NutriGrade were used to assess the quality of evidence in the meta-analysis and umbrella review, respectively.

RESULTS

Forty-five RCTs with 1995 participants were included in the meta-analysis. High MAC intake significantly reduced glycated hemoglobin (HbA1c) (weighted mean difference [WMD] -0.436% [-0.556, -0.315]), fasting glucose (WMD -0.835 mmol/L [-1.048, -0.622]), total cholesterol (WMD -0.293 mmol/L [-0.397, -0.190]), triglycerides (WMD -0.118 mmol/L [-0.308, -0.058]), BMI (WMD -0.476 [-0.641, -0.312]), and systolic blood pressure (WMD -3.066 mmHg [-5.653, -0.478]), with a moderate-to-high quality of evidence, compared with low intake. Region, dose, and MAC type were key variables. The umbrella review of all dietary interventions for cardiovascular risk factors in patients with T2DM included 26 meta-analyses with 158 pooled estimates. The evidence quality of MACs, dietary fiber, high-protein diet, ω-3 (n-3), viscous fiber, vitamin D, and vitamin E intake was moderate to high.

CONCLUSIONS

When compared with lower intake, increased MAC intake improved glycemic control, blood lipid, body weight, and inflammatory markers for people with T2DM. This trial was registered at PROSPERO (https://www.crd.york.ac.uk/PROSPERO/#recordDetails) as CRD42019120531.

Changes in leptin, serotonin, and cortisol after eight weeks of aerobic exercise with probiotic intake in a cuprizone-induced demyelination mouse model of multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is the most common non-traumatic neurological cause of disability in young adults. Physical activity, particularly exercise training, is an evidence-based approach to managing symptoms, restoring function, and improving overall wellness in people with MS. As well, the use of probiotics can be effective in reducing the damage from inflammation in MS patients.

OBJECTIVE

The study aimed to address changes in leptin, serotonin, and cortisol following eight weeks of aerobic exercise along with probiotic intake in a cuprizone-induced demyelination mouse model of MS.

METHODS

Mice were exposed to cuprizone for 12 weeks. After 5 weeks, beam and performance tests were performed on them. The mice (n = 5 per group) were randomly divided into five groups: control (C), MS, MS with exercise (MS + Exe), MS with probiotic (MS + Prob), and MS with probiotic and exercise (MS + Prob + Exe). Exercise groups performed aerobic exercises 5 days a week, 10 min in the first week, 20 min in the second week, and 30 min daily in the third week until the eighth week. In the probiotic groups, the mice received probiotic by gavage. They were sacrificed after 3 months. Biochemical and molecular biology analyses were performed.

RESULTS

The results showed that leptin gene expression values in the MS + Prob + Exe, MS + Prob, and MS + Exe groups showed a decrease compared to the MS group, but the reduction was not significant (p > 0.05). Also, the leptin Elisa test in these intervention groups showed a significant decrease (P < 0.05). The serotonin gene expression values in the MS + Prob + Exe, MS + Prob, and MS + Exe groups were increased compared to the MS group, but the increase was not significant (p > 0.05). Furthermore, the serotonin Elisa test in these intervention groups showed a significant increase (P < 0.05). The cortisol Elisa test values in the MS + Exe and MS + Prob groups exhibited a decrease compared to the MS group, but the reduction was not significant (p > 0.05).

CONCLUSION

Overall, these results suggest that lifestyle interventions can be effective in improving pathological factors in patients with MS.

The effects of nondigestible fermentable carbohydrates on adults with overweight or obesity: a meta-analysis of randomized controlled trials

CONTEXT

Nondigestible fermentable carbohydrates (NDFCs) can be fermented by microbiota, thereby yielding metabolites that have a beneficial role in the prevention and treatment of obesity and its complications. However, to our knowledge, no meta-analysis has been conducted to evaluate the effects of NDFCs on obesity.

OBJECTIVE

To conduct a meta-analysis of randomized controlled trials (RCTs) to summarize existing evidence on the effects of numerous NDFCs on adiposity and cardiovascular risk factors in adults with overweight or obesity with ≥2 weeks of follow-up.

DATA SOURCES

The following databases were searched: MEDLINE, Embase, and CINAHL.

DATA EXTRACTION

Seventy-seven RCTs with 4535 participants were identified for meta-analysis from the 3 databases.

DATA ANALYSIS

The findings suggest that increased intake of NDFCs is significantly effective in reducing body mass index by 0.280 kg/m2, weight by 0.501 kg, hip circumference by 0.554 cm, waist circumference by 0.649 cm, systolic blood pressure by 1.725 mmHg, total cholesterol by 0.36 mmol/L, and low-density lipoprotein by 0.385 mmol/L, with evidence of moderate-to-high quality.

CONCLUSION

Convincing evidence from meta-analyses of RCTs indicates that increased NDFC intake improves adiposity, blood lipid levels, and systolic blood pressure in people with overweight and obesity.

The microbiota-gut-brain axis: A novel nutritional therapeutic target for growth retardation

Growth retardation (GR), which commonly occurs in childhood, is a major health concern globally. However, the specific mechanism remains unclear. It has been increasingly recognized that changes in the gut microbiota may lead to GR through affecting the microbiota-gut-brain axis. Microbiota interacts with multiple factors such as birth to affect the growth of individuals. Microbiota communicates with the nerve system through chemical signaling (direct entry into the circulation system or stimulation of enteroendocrine cells) and nervous signaling (interaction with enteric nerve system and vagus nerve), which modulates appetite and immune response. Besides, they may also influence the function of enteric glial cells or lymphocytes and levels of systemic inflammatory cytokines. Environmental stress may cause leaky gut through perturbing the hypothalamic-pituitary-adrenal axis to further result in GR. Nutritional therapies involving probiotics and pre-/postbiotics are being investigated for helping the patients to overcome GR. In this review, we summarize the role of microbiota in GR with human and animal models. Then, existing and potential regulatory mechanisms are reviewed, especially the effect of microbiota-gut-brain axis. Finally, we propose nutritional therapeutic strategies for GR by the intervention of microbiota-gut-brain axis, which may provide novel perspectives for the treatment of GR in humans and animals.

Prebiotic and probiotic supplementation and the tryptophan-kynurenine pathway: A systematic review and meta analysis

This systematic review aimed to synthesise the results from studies investigating the effects of prebiotics and probiotics on kynurenine pathway metabolism. Thirteen studies were identified for inclusion, comprising 12 probiotic and two prebiotic arms. Participants included healthy individuals and individuals with various clinical conditions. Twelve metabolites were examined across the studies, using a range of biological samples. Across all interventions, 11 reported an effect on ≤ metabolite. Although limited by clinical and methodological heterogeneity, pooled analysis (n = 253) found probiotics to significantly affect serum kynurenine (g = 0.315, CI = 0.070 to 0.560, p = 0.012, 4 studies, I² = 0%) and the kynurenine:tryptophan ratio (g = 0.442, CI = 0.074 to 0.810, p = 0.018, 4 studies, I² = 42 %). Risk of bias across the studies was generally low. The results provide preliminary evidence that probiotics can modulate kynurenine pathway metabolism, with less evidence available regarding prebiotics. Future studies which further consider methodological confounds and sample characteristics are required, to establish intervention efficacy. PROSPERO registration #CRD42019154677.

Resistant Maltodextrin Alleviates Dextran Sulfate Sodium-Induced Intestinal Inflammatory Injury by Increasing Butyric Acid to Inhibit Proinflammatory Cytokine Levels

Inflammatory bowel disease (IBD), one kind of intestinal chronic inflammatory disease, is characterized by colonic epithelial barrier injury, overproduction of proinflammatory cytokines, and fewer short-chain fatty acids (SCFAs). The present study is aimed at testing the hypothesis that resistant maltodextrin (RM), a soluble dietary fiber produced by starch debranching, alleviated dextran sulfate sodium- (DSS-) induced colitis in mice. Female C57BL/6 mice with or without oral administration of 50 mg/kg RM for 19 days were challenged with 3% DSS in drinking water to induce colitis (from day 14 to day 19). Although RM could not reverse DSS-induced weight loss or colon shortening, it reduced inflammatory cell infiltration and epithelial damage in colon tissue, as well as the transfer of intestinal permeability indicators including serum diamine oxidase (DAO) and D-lactic acid (D-LA). ELISA analysis indicated that RM significantly suppressed the increase of Th1 cytokines induced by DSS in the colon such as tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). The levels of proinflammatory cytokines interleukin-1β (IL-1β), IL-17, and IL-8 in the DSS group were significantly higher than those in the control group and RM group, but no significant difference was observed in the RM-DSS group compared with the RM group. Interestingly, IL-10 levels of the DSS group were significantly higher than those of the other groups. With respect to SCFAs, DSS administration significantly decreased the concentration of faecal butyric acid while the RM-DSS group showed a tendency to increase (P = 0.08). In general, RM alleviated dextran sulfate sodium-induced intestinal inflammation through increasing the level of butyric acid and subsequently inhibiting the expression of proinflammatory cytokines.

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.

Gut microbiota-derived metabolite trimethylamine N-oxide (TMAO) potentially increases the risk of obesity in adults: An exploratory systematic review and dose-response meta- analysis

It has been suggested that trimethylamine N-oxide (TMAO) is associated with increased risk of diabetes and cardiovascular disease (CVD) morbidity and mortality. However, it is not known whether increased TMAO concentrations is associated with obesity. In the current study, we summarized the evidence related to the association of circulating TMAO with the risk of obesity measurements, including body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) in a two-class and dose-response meta-analysis of observational studies. A systematic search carried out in PubMed, SCOPUS, Cochrane, and ProQuest through September 30, 2019 resulted in 12 eligible studies which were included in the current meta-synthesis. In these studies, BMI was reported but there were no reports of WC or WHR. Meta-analysis of two-class variables and dose-response meta-analysis of continuous variables were performed. Subgroup analysis and meta-regression were also performed to identify the source of heterogeneity. There was a dose-response association between circulating TMAO concentration and increased BMI in studies involving healthy individuals (P nonlinearity = .007), while no evidence of departure from linearity was observed according to study design or among patients with CVD. Results showed the highest category of TMAO was associated with 0.56 kg/m² increase in BMI (weighted mean difference [WMD], 0.563; CI, 0.026-1.100; P = .04). The results of the current meta-analysis revealed a positive association between circulating TMAO and obesity as presented by increased BMI. Moreover, a dose-dependent association between circulating TMAO and obesity was also identified in apparently healthy individuals. This is the first meta-analysis to reveal positive dose-dependent associations between circulating TMAO concentration and obesity.

Resistant dextrin reduces obesity and attenuates adipose tissue inflammation in high-fat diet-fed mice

Resistant dextrin (RD), a short chain glucose polymer, has been shown to improve type 2 diabetes mellitus (T2DM) in clinical studies. However, the improvement of adipose tissue inflammation and specific mechanisms of RD supplementation in obesity have not been fully investigated. Therefore, we examined whether RD attenuates obesity and adipose tissue inflammation in high-fat diet (HFD)-fed mice. Male C57BL/6 mice were fed a chow diet, a HFD or a HFD with RD supplementation for 12 weeks. Body weight (BW), fasting blood glucose (FBG), epididymal fat accumulation, serum total triglyceride (TG), free fatty acid (FFA) and inflammatory cytokine levels (TNF-α, IL-1β, IL-6, IL-10) were measured. Inflammation markers and macrophage infiltration in epididymal adipose tissue were observed. After 12 weeks of intervention, the body weight gain of mice in RD supplementation group was less than that in HFD group. FBG, epididymal fat accumulation, serum TG and FFA levels were reduced in RD supplementation group compared with HFD group. Moreover, serum and mRNA levels of IL-6 were significantly reduced in the RD supplementation group. In addition, RD supplementation reduced macrophage infiltration, regulated polarization of macrophage and inhibited NF-κB signaling in epididymal adipose tissue. In conclusion, RD reduces obesity and attenuates adipose tissue inflammation in HFD-fed mice, and the inhibition of NF-κB signaling may be a presumed mechanism for its effects.

A Diabetes Self-Management Education/Support (DSME/S) Program in Reference to the Biological, Psychological and Social Aspects of a Patient with Type 2 Diabetes Mellitus: A Systematic Review

Introduction: Various efforts have been made to improve the self-care management of patients with type 2 diabetes mellitus (T2DM). One of them is by using a Diabetes Self-Management Education and Support (DSME/S) program. DSME/S produces positive effects in relation to patient behavior and health status. This is a systematic review of randomized controlled trials published where the aim was to evaluate the impact of the DSME/S program in term of biological. psychological and social aspects.Methods: The articles were searched for using the PRISMA approach from within Scopus, Sage Journal, ProQuest, Google Scholar and PubMed to identify the relevant English publications on DSME over the last 5 years (2013-2018). In total, 15 studies met the inclusion criteria.Results: The articles included at least one result that covered the biological, psychological, and social aspects that are more general and relevant for T2DM patients who received the DSME program. DSME had a positive impact on T2DM, namely the reduction of HbA1c, blood glucose, LDL, cholesterol, blood pressure, weight, waist circumference, decreased distress, anxiety and increased self-efficacy and self-empowerment.Conclusion: It can increase the social and family support, improve self-management motivation, increase knowledge and improve the behavior of T2DM patients. The findings of our review showed that DSME has a positive impact on the biological, psychological and social aspects of type 2 diabetes mellitus.

Prebiotic supplementation modulates advanced glycation end-products (AGEs), soluble receptor for AGEs (sRAGE), and cardiometabolic risk factors through improving metabolic endotoxemia: a randomized-controlled clinical trial

PURPOSE

The oxidative stress plays a key role in the initiation, propagation, and development of the complications of type 2 diabetes mellitus (T2DM). This trial aimed to evaluate the effects of resistant dextrin as a prebiotic on the cardiometabolic risk factors and the status of oxidative stress in patients with T2DM.

METHODS

Sixty-five female subjects with T2DM were assigned to either the intervention (n = 33) or control (n = 32) groups receiving 10 g/day of resistant dextrin or placebo, respectively, for 8 weeks. Fasting blood samples were collected at baseline and post-intervention to determine the serum levels of glycemic indices, lipid profile, atherogenic indices, and soluble receptor for AGEs (sRAGE), carboxymethyl lysine (CML), pentosidine, malondialdehyde (MDA), 8-iso-prostaglandin F2α (8-iso-PGF2α), total antioxidant capacity (TAC), antioxidant enzymes activity, and uric acid. Data were analyzed using SPSS software 17. Paired, unpaired Student's t tests, and analysis of covariance were used to compare the quantitative variables.

RESULTS

Resistant dextrin caused a significant decrease in FPG (- 17.43 mg/dl, 9.80%), TG (- 40.25 mg/dl, 23.01%), TC/HDL (- 0.80, 21.87%), LDL-c/HDL-c (- 0.80, 17.85%), Atherogenic index (- 0.40, 15.80%), LPS (- 6.5 EU/ml, 23.40%) and hs-CRP (- 8.02 ng/ml, 54.00%), MDA (- 1.21 nmol/mL, 25.58%), CML (- 93.40 ng/ml, 26.30%), 8-iso-PGF2α (- 4.65 pg/ml, 15.00%), and a significant increase in TAC (0.33 mmol/L, 36.25%) and s-RAGE (2.10 ng/ml, 28.90%) in the intervention group compared with the control group. No significant changes were observed in glycosylated hemoglobin, total cholesterol, LDL-c, HDL-c, superoxide dismutase, glutathione peroxidase and catalase, pentosidine, and uric acid in the intervention group compared with the control group.

CONCLUSIONS

Supplementation with resistant dextrin may improve the advanced glycation end-products, sRAGE, and cardiometabolic risk factors in women with type 2 diabetes mellitus.

The Microbiota-Gut-Brain Axis

The importance of the gut-brain axis in maintaining homeostasis has long been appreciated. However, the past 15 yr have seen the emergence of the microbiota (the trillions of microorganisms within and on our bodies) as one of the key regulators of gut-brain function and has led to the appreciation of the importance of a distinct microbiota-gut-brain axis. This axis is gaining ever more traction in fields investigating the biological and physiological basis of psychiatric, neurodevelopmental, age-related, and neurodegenerative disorders. The microbiota and the brain communicate with each other via various routes including the immune system, tryptophan metabolism, the vagus nerve and the enteric nervous system, involving microbial metabolites such as short-chain fatty acids, branched chain amino acids, and peptidoglycans. Many factors can influence microbiota composition in early life, including infection, mode of birth delivery, use of antibiotic medications, the nature of nutritional provision, environmental stressors, and host genetics. At the other extreme of life, microbial diversity diminishes with aging. Stress, in particular, can significantly impact the microbiota-gut-brain axis at all stages of life. Much recent work has implicated the gut microbiota in many conditions including autism, anxiety, obesity, schizophrenia, Parkinson’s disease, and Alzheimer’s disease. Animal models have been paramount in linking the regulation of fundamental neural processes, such as neurogenesis and myelination, to microbiome activation of microglia. Moreover, translational human studies are ongoing and will greatly enhance the field. Future studies will focus on understanding the mechanisms underlying the microbiota-gut-brain axis and attempt to elucidate microbial-based intervention and therapeutic strategies for neuropsychiatric disorders.

Regulation of Gut Microbiota and Metabolic Endotoxemia with Dietary Factors

Metabolic endotoxemia is a condition in which blood lipopolysaccharide (LPS) levels are elevated, regardless of the presence of obvious infection. It has been suggested to lead to chronic inflammation-related diseases such as obesity, type 2 diabetes mellitus, non-alcoholic fatty liver disease (NAFLD), pancreatitis, amyotrophic lateral sclerosis, and Alzheimer’s disease. In addition, it has attracted attention as a target for the prevention and treatment of these chronic diseases. As metabolic endotoxemia was first reported in mice that were fed a high-fat diet, research regarding its relationship with diets has been actively conducted in humans and animals. In this review, we summarize the relationship between fat intake and induction of metabolic endotoxemia, focusing on gut dysbiosis and the influx, kinetics, and metabolism of LPS. We also summarize the recent findings about dietary factors that attenuate metabolic endotoxemia, focusing on the regulation of gut microbiota. We hope that in the future, control of metabolic endotoxemia using dietary factors will help maintain human health.

Calorie restriction in combination with prebiotic supplementation in obese women with depression: effects on metabolic and clinical response

BACKGROUND

Major depressive disorder (MDD) is a common psychiatric disorder, closely associated with obesity. This study aimed to assess the effects of prebiotics combined with calorie restriction on clinical and metabolic response in obese women with MDD.

METHODS

In an 8-week double-blind placebo-controlled randomized clinical trial, 62 obese women with MDD were equally allocated into either prebiotic (10 g/day Inulin) or placebo (10 g/day Maltodextrin) group. In addition, all the participants were also prescribed a 25% calorie-restricted diet (registration ID: IRCT20100209003320N15). Depression was assessed by Hamilton depression rating scale (HDRS) and Beck depression inventory (BDI-II) pre- and post-intervention. Anthropometric measures, fasting serum levels of glucose, insulin and lipid profile were assessed, and dietary assessments were performed pre- and post-intervention. Insulin resistance was estimated by homeostasis model assessment of insulin resistance (HOMA-IR).

RESULTS

45 patients completed the trial. There were no significant between-group differences for MDD symptoms and other study outcomes, post-intervention. Weight, waist and hip circumferences, systolic blood pressure, and HDRS score significantly decreased in both groups, while fat mass and total cholesterol (TC) declined only in the prebiotic arm. Those who had ≥1.9 kg weight loss showed significantly improved HDRS score, compared to women with <1.9 kg weight reduction, irrespective of the supplement they took.

CONCLUSION

Although prebiotic supplementation had some beneficial metabolic effects, calorie restriction and weight loss seem to play a more important role in improving depressive symptoms among obese women with MDD.

Effects of regulating intestinal microbiota on anxiety symptoms: A systematic review

Background

Anxiety symptoms are common in mental diseases and a variety of physical disorders, especially in disorders related to stress. More and more basic studies have indicated that gut microbiota can regulate brain function through the gut-brain axis, and dysbiosis of intestinal microbiota was related to anxiety. However, there is no specific evidence to support treatment of anxiety by regulating intestinal microbiota.

Aims

To find evidence supporting improvement of anxiety symptoms by regulation of intestinal microbiota.

Methods

This systematic review of randomised controlled trials was searched based on the following databases: PubMed, EMBASE, the Cochrane Library, OVID, Web of Knowledge, China National Knowledge Infrastructure (CNKI), Wanfang Data, VIP databases and SinoMed. The retrieval time dated back to 25 July 2018. Then we screened research literatures based on established inclusion and exclusion criteria. Quality evaluation for each included study was done using the Cochrane risk of bias and the Jadad scale.

Results

A total of 3334 articles were retrieved and 21 studies were included which contained 1503 subjects. In the 21 studies, 14 chose probiotics as interventions to regulate intestinal microbiota and six chose non-probiotic ways such as adjusting daily diets. Probiotic supplements in seven studies contained only one kind of probiotic, two studies used a product that contained two kinds of probiotics and the supplements used in the other five studies included at least three kinds of probiotics. In the studies that used treatment as usual plus interventions regulating intestinal flora (IRIF) as interventions (five studies), only non-probiotic ways were effective (two studies), which means 40% of studies were effective; in the studies that used IRIF alone (16 studies, 11 studies used probiotic ways and 5 studies used non-probiotic ways), 56% of studies could improve anxiety symptoms, and 80% of studies that conducted the non-probiotic interventions were effective, while 45% of studies that used probiotic supplementations had positive effects on anxiety symptoms. Overall, 11 studies showed a positive effect on anxiety symptoms by regulating intestinal microbiota, which indicated 52% of the 21 studies were effective, and there were five studies that used probiotic supplements as interventions and six used non-probiotic interventions. In addition, it should be noted that six of seven studies showed that regulation of intestinal microbiota could treat anxiety symptoms, the rate of efficacy was 86%.

Conclusions

We find that more than half of the studies included showed it was positive to treat anxiety symptoms by regulation of intestinal microbiota. There are two kinds of interventions (probiotic and non-probiotic interventions) to regulate intestinal microbiota, and it should be highlighted that the non-probiotic interventions were more effective than the probiotic interventions. More studies are needed to clarify this conclusion since we still cannot run meta-analysis so far.

Use of Lactobacillus crispatus to produce a probiotic cheese as potential gender food for preventing gynaecological infections

This research is aimed to evaluate the suitability of Squacquerone cheese to support the viability of Lactobacillus crispatus BC4, a vaginal strain endowed with a strong antimicrobial activity against urogenital pathogens and foodborne microorganisms, in order to recommend a gender food for woman wellbeing. The viability of L. crispatus BC4, used as adjunct culture, was evaluated during the refrigerated storage of Squacquerone cheese, as well as when the cheese was subjected to simulated stomach-duodenum passage tested by the patented Simulator of the Human Intestinal Microbial Ecosystem (SHIME). Moreover, the effects of L. crispatus BC4 addition were evaluated on product hydrolytic patterns, in terms of proteolysis, lipolysis and volatile molecule profiles. The data showed that L. crispatus BC4 maintained high viability, also in presence of physiological stress conditions, until the end of the refrigerated storage. Moreover, the inclusion of L. crispatus BC4 gave rise to cheese product with higher score of overall acceptability when compared to control cheese. In addition, the survival of L. crispatus BC4, carried in test cheese, in gastro intestinal conditions was confirmed by SHIME. The results showed that the vaginal Lactobacillus strain was more affected by the low pH of the stomach, simulated by the SHIME reactor, rather than to bile salts and pancreatic juices. Although only in vivo trials will be able to confirm the functionality of the cheese in the vaginal environment, these data represent a first step towards the employment of the Squacquerone cheese as probiotic food able to promote the woman’s health by preventing gynaecological infections.