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The Role of Lung and Gut Microbiota in the Pathology of Asthma.
Barcik, W, Boutin, RCT, Sokolowska, M, Finlay, BB
Immunity. 2020;52(2):241-255
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Over 300 million people suffer with asthma worldwide and it has emerged that microbiome analysis of the lung and gut bacteria, fungi, viruses, and archaea may help with disease management. This microbiome plays an important role in immune response. Disturbances to these microbes, known as dysbiosis, may influence onset of disease and the body’s ability to respond naturally, and/or to pharmaceutical treatments. Asthma is not a singular disease and there are great variations in symptom severity and underlying immune mechanisms. Patients are typically classified as type 2 or non-type 2. Type 2 patients tend to be allergic to common air-born allergens which can trigger an attack. Treatment usually consists of glucocorticosteroids or novel biologicals. Non type-2 asthma is associated with obesity-related asthma and typically responds poorly to steroid treatment. For a long time, researchers believed the human lungs to be sterile, so they were initially not included in the 2007 Human Microbiome Project. It has since been shown that, like the gut, the lungs and respiratory tract also host various microbes, and this healthy-airway microbiota influence innate and adaptive immune processes. The Gut-Lung axis also confers additional microbial benefits from the intestines. In asthma patients, there is often an over-dominance of pathogenic bacteria. Fungal dysbiosis is associated with high-risk asthma phenotypes in childhood. Viral infections have been shown as a primary cause of asthmatic episodes. Future diagnosis and treatment of patients with asthma should be assisted by analysis of the composition and metabolic activity of an individual’s microbiome.
Abstract
Asthma is a common chronic respiratory disease affecting more than 300 million people worldwide. Clinical features of asthma and its immunological and molecular etiology vary significantly among patients. An understanding of the complexities of asthma has evolved to the point where precision medicine approaches, including microbiome analysis, are being increasingly recognized as an important part of disease management. Lung and gut microbiota play several important roles in the development, regulation, and maintenance of healthy immune responses. Dysbiosis and subsequent dysregulation of microbiota-related immunological processes affect the onset of the disease, its clinical characteristics, and responses to treatment. Bacteria and viruses are the most extensively studied microorganisms relating to asthma pathogenesis, but other microbes, including fungi and even archaea, can potently influence airway inflammation. This review focuses on recently discovered connections between lung and gut microbiota, including bacteria, fungi, viruses, and archaea, and their influence on asthma.
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Gut microbiota plasticity is correlated with sustained weight loss on a low-carb or low-fat dietary intervention.
Grembi, JA, Nguyen, LH, Haggerty, TD, Gardner, CD, Holmes, SP, Parsonnet, J
Scientific reports. 2020;10(1):1405
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Obesity is responsible for a substantial number of deaths and is associated with considerable economic costs. Dietary intervention can help with weight loss; however, success varies between individuals. Gut microbiota could influence weight loss as they have been shown in previous studies to affect feelings of hunger. This cohort study taken from an RCT of 161 obese adults aimed to determine if differing gut microbiota communities could be involved in determining weight loss success when on a low-carbohydrate or a low-fat diet over 12 months. The results showed that specific gut microbiota did not predict weight loss success. However, having a diverse gut microbiota prior to starting a low-fat diet, predicted higher weight loss. This was only observed in those on a low-carbohydrate diet after 10 weeks of dieting. Interestingly individuals that reported better dietary adherence weren’t necessarily more successful with weight loss. It was concluded that gut microbiota diversity is important in sustained weight loss, especially if on a low-fat diet. This study could be used by healthcare professionals to understand that microbial diversity may determine the success of a diet regime and the importance of personalising recommendations.
Abstract
While low-carbohydrate and low-fat diets can both lead to weight-loss, a substantial variability in achieved long-term outcomes exists among obese but otherwise healthy adults. We examined the hypothesis that structural differences in the gut microbiota explain a portion of variability in weight-loss using two cohorts of obese adults enrolled in the Diet Intervention Examining The Factors Interacting with Treatment Success (DIETFITS) study. A total of 161 pre-diet fecal samples were sequenced from a discovery cohort (n = 66) and 106 from a validation cohort (n = 56). An additional 157 fecal samples were sequenced from the discovery cohort after 10 weeks of dietary intervention. We found no specific bacterial signatures associated with weight loss that were consistent across both cohorts. However, the gut microbiota plasticity (i.e. variability), was correlated with long-term (12-month) weight loss in a diet-dependent manner; on the low-fat diet subjects with higher pre-diet daily plasticity had higher sustained weight loss, whereas on the low-carbohydrate diet those with higher plasticity over 10 weeks of dieting had higher 12-month weight loss. Our findings suggest the potential importance of gut microbiota plasticity for sustained weight-loss. We highlight the advantages of evaluating kinetic trends and assessing reproducibility in studies of the gut microbiota.
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Non-Systematic Review of Diet and Nutritional Risk Factors of Cardiovascular Disease in Obesity.
Rychter, AM, Ratajczak, AE, Zawada, A, Dobrowolska, A, Krela-Kaźmierczak, I
Nutrients. 2020;12(3)
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Nutrition is a major factor influencing obesity associated heart disease risk, however many people with this disease do not follow nutritional recommendations. This review of 155 studies aimed to summarise dietary aspects of heart disease prevention. The paper began by outlining the role of obesity through the development of other disorders that contribute to heart disease, such as type 2 diabetes, high blood pressure and blood sugar imbalance. The quantity and distribution of fat tissue also can contribute to heart disease risk, especially if it is located within the heart or around the major organs of the body. Dietary factors which can increase heart disease risk were described as an increased intake of processed foods, sugar, salt and certain fats and low intakes of fruit, vegetables, fibre, whole grains, beans and nuts. The Mediterranean diet, the dietary approaches to stop hypertension (DASH) diet, plant-based diets, the portfolio dietary pattern and low carbohydrate diets were all reviewed and although mixed results were stated for low carbohydrate diets, most of the diets reviewed reported improved heart disease outcomes. The role of intestinal microbiota in heart disease were also reviewed and the influence of a poor diet was implicated in imbalanced gut microbiota and the development of heart disease. It was concluded that an unhealthy diet can contribute to heart disease and that dietary patterns such as the Mediterranean diet and plant-based diets may be favourable for its management. This study could be used by healthcare professionals to individualise dietary recommendations for patients with heart disease or who are at risk of it.
Abstract
Although cardiovascular disease and its risk factors have been widely studied and new methods of diagnosis and treatment have been developed and implemented, the morbidity and mortality levels are still rising-cardiovascular disease is responsible for more than four million deaths each year in Europe alone. Even though nutrition is classified as one of the main and changeable risk factors, the quality of the diet in the majority of people does not follow the recommendations essential for prevention of obesity and cardiovascular disease. It demonstrates the need for better nutritional education in cardiovascular disease prevention and treatment, and the need to emphasize dietary components most relevant in cardiovascular disease. In our non-systematic review, we summarize the most recent knowledge about nutritional risk and prevention in cardiovascular disease and obesity.
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Walnuts and Vegetable Oils Containing Oleic Acid Differentially Affect the Gut Microbiota and Associations with Cardiovascular Risk Factors: Follow-up of a Randomized, Controlled, Feeding Trial in Adults at Risk for Cardiovascular Disease.
Tindall, AM, McLimans, CJ, Petersen, KS, Kris-Etherton, PM, Lamendella, R
The Journal of nutrition. 2020;150(4):806-817
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Recent evidence suggests that microbes present in the gut may have a role in the risk of heart disease development. Walnuts have in previous studies shown to be of benefit for cardiovascular health and gut microbes are thought to be the mediator of this. This secondary analysis of a randomised control trial aimed to assess diets which differentiated in walnut composition on the species diversity of gut microbes and heart disease risk in 46 individuals with obesity over an 18-week period. The results showed that a diet of walnuts and the fats they contain enriched the microbes present in the gut compared to a Western-style diet. Interestingly, a whole walnut diet showed enrichment of a species that is better able to break down and use the components of walnuts compared to a diet where only the walnut fats were present. When on a diet rich in walnuts, an increase in a species of gut bacteria related to improved heart disease risk factors was observed. It was concluded that the positive effects of walnuts on gut bacteria and heart disease risk are due to the fibre and bioactive compounds, not simply the fats they contain. This study could be used by health care professionals to recommend the inclusion of whole walnuts into the diet of individuals with obesity to enrich gut bacteria that are involved in reducing heart disease risk.
Abstract
BACKGROUND It is unclear whether the favorable effects of walnuts on the gut microbiota are attributable to the fatty acids, including α-linolenic acid (ALA), and/or the bioactive compounds and fiber. OBJECTIVE This study examined between-diet gut bacterial differences in individuals at increased cardiovascular risk following diets that replace SFAs with walnuts or vegetable oils. METHODS Forty-two adults at cardiovascular risk were included in a randomized, crossover, controlled-feeding trial that provided a 2-wk standard Western diet (SWD) run-in and three 6-wk isocaloric study diets: a diet containing whole walnuts (WD; 57-99 g/d walnuts; 2.7% ALA), a fatty acid-matched diet devoid of walnuts (walnut fatty acid-matched diet; WFMD; 2.6% ALA), and a diet replacing ALA with oleic acid without walnuts (oleic acid replaces ALA diet; ORAD; 0.4% ALA). Fecal samples were collected following the run-in and study diets to assess gut microbiota with 16S rRNA sequencing and Qiime2 for amplicon sequence variant picking. RESULTS Subjects had elevated BMI (30 ± 1 kg/m2), blood pressure (121 ± 2/77 ± 1 mmHg), and LDL cholesterol (120 ± 5 mg/dL). Following the WD, Roseburia [relative abundance (RA) = 4.2%, linear discriminant analysis (LDA) = 4], Eubacterium eligensgroup (RA = 1.4%, LDA = 4), LachnospiraceaeUCG001 (RA = 1.2%, LDA = 3.2), Lachnospiraceae UCG004 (RA = 1.0%, LDA = 3), and Leuconostocaceae (RA = 0.03%, LDA = 2.8) were most abundant relative to taxa in the SWD (P ≤ 0.05 for all). The WD was also enriched in Gordonibacter relative to the WFMD. Roseburia (3.6%, LDA = 4) and Eubacterium eligensgroup (RA = 1.5%, LDA = 3.4) were abundant following the WFMD, and Clostridialesvadin BB60group (RA = 0.3%, LDA = 2) and gutmetagenome (RA = 0.2%, LDA = 2) were most abundant following the ORAD relative to the SWD (P ≤ 0.05 for all). Lachnospiraceae were inversely correlated with blood pressure and lipid/lipoprotein measurements following the WD. CONCLUSIONS The results indicate similar enrichment of Roseburia following the WD and WFMD, which could be explained by the fatty acid composition. Gordonibacter enrichment and the inverse association between Lachnospiraceae and cardiovascular risk factors following the WD suggest that the gut microbiota may contribute to the health benefits of walnut consumption in adults at cardiovascular risk. This trial was registered at clinicaltrials.gov as NCT02210767.
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Effect of Hesperidin on Cardiovascular Disease Risk Factors: The Role of Intestinal Microbiota on Hesperidin Bioavailability.
Mas-Capdevila, A, Teichenne, J, Domenech-Coca, C, Caimari, A, Del Bas, JM, Escoté, X, Crescenti, A
Nutrients. 2020;12(5)
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Cardiovascular diseases (CVDs) cause around 31% of all deaths worldwide. Certain dietary patterns have been associated with a reduction in CVDs and so the use of natural-based products has gained importance as a preventive strategy. Hesperidin is a bioactive compound found in high levels in citrus fruits. The reported beneficial properties include antitumor, antioxidant, anti-inflammatory; cholesterol and glucose lowering effects. Many animal studies show multiple beneficial effects but are inconclusive in human studies. The aim of this review is to describe the effects of hesperidin on CVD factors and to highlight the individual differences in its bioavailability and effectiveness. The gut bacteria play an important role in this. Hesperidin is not broken down by the normal digestive process and reaches the colon largely intact. It is the job of the gut bacteria to break it down into bioavailable substances that can be absorbed and utilised. The discrepancies observed in some of the results from human clinical trials may be partly due to individual differences, including that of the gut bacteria. Further clinical trials should be considered as well as classifying individuals according to individual differences in metabotypes.
Abstract
Recently, hesperidin, a flavonone mainly present in citrus fruits, has emerged as a new potential therapeutic agent able to modulate several cardiovascular diseases (CVDs) risk factors. Animal and in vitro studies demonstrate beneficial effects of hesperidin and its derived compounds on CVD risk factors. Thus, hesperidin has shown glucose-lowering and anti-inflammatory properties in diabetic models, dyslipidemia-, atherosclerosis-, and obesity-preventing effects in CVDs and obese models, and antihypertensive and antioxidant effects in hypertensive models. However, there is still controversy about whether hesperidin could contribute to ameliorate glucose homeostasis, lipid profile, adiposity, and blood pressure in humans, as evidenced by several clinical trials reporting no effects of treatments with this flavanone or with orange juice on these cardiovascular parameters. In this review, we focus on hesperidin's beneficial effects on CVD risk factors, paying special attention to the high interindividual variability in response to hesperidin-based acute and chronic interventions, which can be partly attributed to differences in gut microbiota. Based on the current evidence, we suggest that some of hesperidin's contradictory effects in human trials are partly due to the interindividual hesperidin variability in its bioavailability, which in turn is highly dependent on the α-rhamnosidase activity and gut microbiota composition.
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6.
Probiotics for Immunity – a Look at the Research
OptiBac Probiotics specialise entirely in probiotics. One of their core values is encouraging people to take health into their own hands in a responsible manner. Training and education is a cornerstone of this, and with their expertise, they hope to help raise awareness of probiotics and their potential to help change lives.
2020
Abstract
This blog post presents the evidence available about the links between the gut microbiome, probiotics and the human immune system. With a useful run through of the different aspects of our immune systems, it provides details of the evidence for specific probiotic strains and in what circumstances they can be effectively and safely used to boost immunity.
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The Differences between Gluten Sensitivity, Intestinal Biomarkers and Immune Biomarkers in Patients with First-Episode and Chronic Schizophrenia.
Dzikowski, M, Juchnowicz, D, Dzikowska, I, Rog, J, Próchnicki, M, Kozioł, M, Karakula-Juchnowicz, H
Journal of clinical medicine. 2020;9(11)
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Schizophrenia is a heterogeneous neuroimmune disorder with unknown mechanisms and aetiology. The goal of this clinical study was to compare and evaluate IgG and IgA sensitivity, inflammation, and gut integrity between 52 first episode Schizophrenia patients, 50 chronic Schizophrenia patients, and 60 healthy controls to explain whether there were any associations between these markers. Study results show that antigliadin IgG and IgA antibodies, as well as inflammatory markers such as hs-CRP and IL-6, were significantly higher in the first episodes of schizophrenia and chronic schizophrenia patients when compared to the healthy controls. Schizophrenia risk was 4-7% higher among those with elevated Antigliadin IgG and IgA antibody levels. In addition, smoking cigarettes has been shown to increase the risk of developing schizophrenia. Patients with chronic schizophrenia showed elevated levels of anti-Saccharomyces cerevisiae antibody and soluble CD14, indicating bacterial translocation and immune activation. To understand the mechanisms behind chronic Schizophrenia, which link inflammation, immune responses, and the gut-brain axis, further robust larger studies are necessary. The results of this study can be used by healthcare professionals to understand the relationship between intestinal permeability, inflammation, and food hypersensitivity.
Abstract
Schizophrenia is a heterogeneous disorder without a fully elucidated etiology and mechanisms. One likely explanation for the development of schizophrenia is low-grade inflammation, possibly caused by processes in the gastrointestinal tract related to gluten sensitivity. The aims of this study were to: (1) compare levels of markers of gluten sensitivity, inflammation and gut permeability, and (2) determine associations between gluten sensitivity, inflammation, and intestinal permeability in patients with first-episode/chronic (FS/CS) schizophrenia and healthy individuals (HC). The total sample comprised 162 individuals (52 FS; 50 CS, and 60 HC). The examination included clinical variables, nutritional assessment, and serum concentrations of: high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), soluble CD14 (sCD14), anti-Saccharomyces cerevisiae antibody (ASCA), antigliadin antibodies (AGA) IgA/IgG, antibodies against tissue transglutaminase 2 (anti-tTG) IgA, anti-deamidated gliadin peptides (anti-DGP) IgG. A significant difference between groups was found in sCD14, ASCA, hs-CRP, IL-6 and AGA IgA levels. AGA IgG/IgA levels were higher in the FS (11.54%; 30.77%) and CS (26%; 20%) groups compared to HC. The association between intestinal permeability and inflammation in the schizophrenic patients only was noted. The risk for developing schizophrenia was odds ratio (OR) = 4.35 (95% confidence interval (CI 1.23-15.39) for AGA IgA and 3.08 (95% CI 1.19-7.99) for positive AGA IgG. Inflammation and food hypersensitivity reactions initiated by increased intestinal permeability may contribute to the pathophysiology of schizophrenia. The immune response to gluten in FS differs from that found in CS.
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Effects of oral probiotic supplements on vaginal microbiota during pregnancy: a randomised, double-blind, placebo-controlled trial with microbiome analysis.
Husain, S, Allotey, J, Drymoussi, Z, Wilks, M, Fernandez-Felix, BM, Whiley, A, Dodds, J, Thangaratinam, S, McCourt, C, Prosdocimi, EM, et al
BJOG : an international journal of obstetrics and gynaecology. 2020;127(2):275-284
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Bacterial vaginosis (BV), in which the normally dominant lactobacilli of the vagina are replaced with anaerobic bacteria, is associated with adverse pregnancy outcomes including preterm birth (PTB). Antibiotics are effective in eradicating BV during pregnancy and are recommended for use in symptomatic pregnant women. The aim of this study was to determine the biological effects of oral probiotics on the vaginal microbiota and the feasibility of conducting a full-scale trial of oral probiotic supplementation of women from early pregnancy to delivery in preventing PTB. This study is a pragmatic randomised, double-blind, placebo-controlled trial with microbiome analysis. The study recruited pregnant women in early pregnancy who were randomised to one of the two groups: intervention or control. Results show that daily oral administration of probiotics from early pregnancy did not affect the prevalence of BV, common neonatal pathogens or alter the composition of the vaginal microbiota at 18–20 weeks’ gestation. Authors conclude that their findings did not show evidence of an effect of oral probiotics on the vaginal microbiota in pregnancy.
Abstract
OBJECTIVE To determine the effects on the vaginal microbiota of an oral probiotic preparation administered from early pregnancy. DESIGN Randomised, double blind, placebo-controlled trial. SETTING Four maternity units in the UK. POPULATION Women aged 16 years or older recruited at 9-14 weeks' gestation. METHODS Participants were randomly allocated to receive oral capsules of probiotic containing Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 each at 2.5 × 109 colony-forming units (CFUs) or placebo once daily from recruitment until the end of pregnancy. MAIN OUTCOME MEASURE Rates of bacterial vaginosis (BV, defined as Nugent score ≥7) at 18-20 weeks' gestation compared by logistic regression adjusted for possible confounders. RESULTS The primary analysis included 78% (238/304) of participants who initially consented (probiotic group 123, placebo group 115). Of these participants, 95% (227/238) reported an intake of 93% or more of the required number of capsules. The rates of BV did not differ between groups at 18-20 weeks' gestation (15% (19/123) in the probiotic group vs. 9% (10/115) in the placebo group, adjusted odds ratio 1.82, 95% confidence interval 0.64-5.19). There were also no differences between the groups in the proportion of women colonised with the probiotic strains, Escherichia coli, group B streptococci or other vaginal microbiota. There were no differences in the alpha diversity or composition of the bacterial communities between or within the probiotic and placebo groups at 9-14 and 18-20 weeks' gestation. CONCLUSIONS Oral probiotics taken from early pregnancy did not modify the vaginal microbiota. TWEETABLE ABSTRACT The oral probiotic preparation used in this study does not prevent BV in pregnant women.
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PROFAST: A Randomized Trial Assessing the Effects of Intermittent Fasting and Lacticaseibacillus rhamnosus Probiotic among People with Prediabetes.
Tay, A, Pringle, H, Penning, E, Plank, LD, Murphy, R
Nutrients. 2020;12(11)
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The prevalence of diabetes is increasing worldwide, and with it, the risk of cardiovascular disease is also increasing. Intermittent fasting has been shown to reduce weight and improve glycaemic control. Weight control and glycaemic control were also improved with probiotic Lacticaseibacillus rhamnosus HN001 supplementation. This pilot, 12-week, double-blinded, two-armed, randomized 1:1 study aimed to investigate the combined effects of intermittent fasting with daily probiotic Lacticaseibacillus rhamnosus HN001 supplementation on glycaemic management in participants with prediabetes. For two days, participants restricted their calorie intake to 600-650 kcal, followed by five days of ad libitum consumption (5:2). Intermittent fasting for 12 weeks improved glycaemic control (reduced HbA1c) and reduced body weight by 5%. The supplementation with Lacticaseibacillus rhamnosus HN001 did not significantly improve these outcomes. Probiotic supplementation significantly improved mental health and social functioning in participants. There is a need for further large, robust studies to assess the effects of intermittent fasting alone and when it is combined with different exercise forms and different prebiotic and probiotic supplements on cardiometabolic markers and mental health. The findings of this study may be useful to healthcare professionals in understanding the effects of fasting on metabolism as well as the psychological benefits of Lacticaseibacillus rhamnosus HN001 supplementation.
Abstract
Both intermittent fasting and specific probiotics have shown promise in improving glucose tolerance with a potential for synergistic effects through alterations to gut microbiota. In this randomized, double-blinded, two-arm feasibility study, we investigated whether intermittent fasting, supplemented with Lacticaseibacillus rhamnosus HN001 probiotic, reduces HbA1c in individuals with prediabetes. All participants with HbA1c 40-50 mmol/mol commenced intermittent fasting (2 days per week of calorie restriction to 600-650 kcal/day) and were randomized 1:1 to either daily probiotic (Lacticaseibacillus rhamnosus HN001) or placebo for 12 weeks. The primary outcome was a change in HbA1c. Secondary outcomes included changes in anthropometry, body composition, glucoregulatory markers, lipids, hunger hormones, liver enzymes, inflammatory markers, gut hormones, calorie and macronutrient intake, quality of life, hunger, mood and eating behavior. Of 33 participants who commenced the trial, 26 participants (mean age 52 years, body mass index (BMI) 34.7 kg/m2) completed the intervention (n = 11 placebo, n = 15 probiotic). HbA1c decreased from 43 ± 2.7 mmol/mol to 41 ± 2.3 mmol/mol, p < 0.001, with average of 5% weight loss. No significant between-group differences were seen in primary or secondary outcomes except for social functioning (p = 0.050) and mental health (p = 0.007) scores as improvements were seen in the probiotic group, but not in the placebo group. This study shows additional psychological benefits of probiotic supplementation during intermittent fasting to achieve weight loss and glycemic improvement in prediabetes.
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Link between gut microbiota and health outcomes in inulin -treated obese patients: Lessons from the Food4Gut multicenter randomized placebo-controlled trial.
Hiel, S, Gianfrancesco, MA, Rodriguez, J, Portheault, D, Leyrolle, Q, Bindels, LB, Gomes da Silveira Cauduro, C, Mulders, MDGH, Zamariola, G, Azzi, AS, et al
Clinical nutrition (Edinburgh, Scotland). 2020;39(12):3618-3628
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A global obesity epidemic has become a growing concern today. Modifying the microbial population in our gut has been identified as a nutritional intervention strategy for managing obesity. Fermentable dietary fibres such as inulin-type fructans may alter the microbial population in the gut. In this randomised, single-blind, multicentric, placebo-controlled study, researchers examined the effect of 16g/d native inulin supplementation with inulin-rich vegetables on obesity and gut bacteria composition over three months in 106 Caucasian subjects. Furthermore, the study examined the synergistic effects of metformin and inulin on gut microbial composition. 75% of the participants lost body weight after taking inulin and making dietary changes. In addition, BMI, fat mass and other metabolic markers decreased in this group. Combined with inulin, metformin showed gut microbial modulation, although an increase in Bifidobacterium species was less noticeable. Supplementing inulin with inulin-rich vegetables caused uncomfortable side effects such as bloating and flatulence. Even though subjects showed a reduction in side effects after the first month of supplementation, it should be considered when making intervention decisions for people prone to digestive issues. Nutrition practitioners can use these results when developing obesity intervention strategies.
Abstract
BACKGROUND The gut microbiota is altered in obesity and is strongly influenced by nutrients and xenobiotics. We have tested the impact of native inulin as prebiotic present in vegetables and added as a supplement on gut microbiota-related outcomes in obese patients. Metformin treatment was analyzed as a potential modulator of the response. METHODS A randomized, single-blinded, multicentric, placebo-controlled trial was conducted in 150 obese patients who received 16 g/d native inulin versus maltodextrin, coupled to dietary advice to consume inulin-rich versus -poor vegetables for 3 months, respectively, in addition to dietary caloric restriction. Anthropometry, diagnostic imaging (abdominal CT-scan, fibroscan), food-behavior questionnaires, serum biology and fecal microbiome (primary outcome; 16S rDNA sequencing) were analyzed before and after the intervention. RESULTS Both placebo and prebiotic interventions lowered energy intake, BMI, systolic blood pressure, and serum γ-GT. The prebiotic induced greater weight loss and additionally decreased diastolic blood pressure, AST and insulinemia. Metformin treatment compromised most of the gut microbiota changes and metabolic improvements linked to prebiotic intervention. The prebiotic modulated specific bacteria, associated with the improvement of anthropometry (i.e. a decrease in Desulfovibrio and Clostridium sensu stricto). A large increase in Bifidobacterium appears as a signature of inulin intake rather than a driver of prebiotic-linked biological outcomes. CONCLUSIONS Inulin-enriched diet is able to promote weight loss in obese patients, the treatment efficiency being related to gut microbiota characteristics. This treatment is more efficacious in patients who did not receive metformin as anti-diabetic drugs prior the intervention, supporting that both drug treatment and microbiota might be taken into account in personalized nutrition interventions. Registered under ClinicalTrials.gov Identifier no NCT03852069.