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Aims: The growing interest in epicardial adipose tissue (EAT) as a biomarker of atrial fibrillation is limited by the difficulties in isolating EAT from other paracardial adipose tissues. We tested the feasibility and value of measuring the pure EAT contained in the atrioventricular groove (GEAT) using cardiovascular magnetic resonance (CMR) imaging in patients with distinct metabolic disorders. Methods and results: CMR was performed on 100 patients from the MetaCardis cohort: obese (n = 18), metabolic syndrome (MSD) (n = 25), type-2 diabetes (T2D) (n = 42), and age- and gender-matched healthy controls (n = 15). GEAT volume measured from long-axis views was obtained in all patients with a strong correlation between GEAT and atrial EAT (r = 0.95; P < 0.0001). GEAT volume was higher in the three groups of patients with metabolic disorders and highest in the MSD group compared with controls. GEAT volume, as well as body mass and body fat, allowed obese, T2D, and MSD patients to be distinguished from controls. GEAT T1 relaxation and peak longitudinal left atrial (LA) strain in CMR were decreased in T2D patients. Logistic regression and random forest machine learning methods were used to create an algorithm combining GEAT volume, GEAT T1, and peak LA strain to identify T2D patients from other groups with an area under curve (AUC) of 0.81 (Se: 77%, Spe: 80%; 95% confidence interval 0.72-0.91, P < 0.0001). Conclusion: Atrioventricular groove adipose tissue characteristics measured during routine CMR can be used as a proxy of atrial EAT and integrated in a multi-parametric CMR biomarker for early identification of atrial cardiomyopathy.
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BACKGROUND: Persons living with HIV (PWH) harbor an altered gut microbiome (higher abundance of Prevotella and lower abundance of Bacillota and Ruminococcus lineages) compared to non-infected individuals. Some of these alterations are linked to sexual preference and others to the HIV infection. The relationship between these lineages and metabolic alterations, often present in aging PWH, has been poorly investigated. METHODS: In this study, we compared fecal metagenomes of 25 antiretroviral-treatment (ART)-controlled PWH to three independent control groups of 25 non-infected matched individuals by means of univariate analyses and machine learning methods. Moreover, we used two external datasets to validate predictive models of PWH classification. Next, we searched for associations between clinical and biological metabolic parameters with taxonomic and functional microbiome profiles. Finally, we compare the gut microbiome in 7 PWH after a 17-week ART switch to raltegravir/maraviroc. RESULTS: Three major enterotypes (Prevotella, Bacteroides and Ruminococcaceae) were present in all groups. The first Prevotella enterotype was enriched in PWH, with several of characteristic lineages associated with poor metabolic profiles (low HDL and adiponectin, high insulin resistance (HOMA-IR)). Conversely butyrate-producing lineages were markedly depleted in PWH independently of sexual preference and were associated with a better metabolic profile (higher HDL and adiponectin and lower HOMA-IR). Accordingly with the worst metabolic status of PWH, butyrate production and amino-acid degradation modules were associated with high HDL and adiponectin and low HOMA-IR. Random Forest models trained to classify PWH vs. control on taxonomic abundances displayed high generalization performance on two external holdout datasets (ROC AUC of 80-82%). Finally, no significant alterations in microbiome composition were observed after switching to raltegravir/maraviroc. CONCLUSION: High resolution metagenomic analyses revealed major differences in the gut microbiome of ART-controlled PWH when compared with three independent matched cohorts of controls. The observed marked insulin resistance could result both from enrichment in Prevotella lineages, and from the depletion in species producing butyrate and involved into amino-acid degradation, which depletion is linked with the HIV infection.
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Microbioma Gastrointestinal , Infecções por HIV , Resistência à Insulina , Humanos , Microbioma Gastrointestinal/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Fezes/microbiologia , Antirretrovirais/uso terapêutico , MetagenomaRESUMO
Glutamine and glutamate are interconverted by several enzymes and alterations in this metabolic cycle are linked to cardiometabolic traits. Herein, we show that obesity-associated insulin resistance is characterized by decreased plasma and white adipose tissue glutamine-to-glutamate ratios. We couple these stoichiometric changes to perturbed fat cell glutaminase and glutamine synthase messenger RNA and protein abundance, which together promote glutaminolysis. In human white adipocytes, reductions in glutaminase activity promote aerobic glycolysis and mitochondrial oxidative capacity via increases in hypoxia-inducible factor 1α abundance, lactate levels and p38 mitogen-activated protein kinase signalling. Systemic glutaminase inhibition in male and female mice, or genetically in adipocytes of male mice, triggers the activation of thermogenic gene programs in inguinal adipocytes. Consequently, the knockout mice display higher energy expenditure and improved glucose tolerance compared to control littermates, even under high-fat diet conditions. Altogether, our findings highlight white adipocyte glutamine turnover as an important determinant of energy expenditure and metabolic health.
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Adipócitos , Metabolismo Energético , Glutaminase , Camundongos Knockout , Animais , Glutaminase/metabolismo , Camundongos , Humanos , Masculino , Adipócitos/metabolismo , Feminino , Obesidade/metabolismo , Resistência à Insulina , Glutamina/metabolismo , Dieta Hiperlipídica , GlicóliseRESUMO
Amino acids, metabolized by host cells as well as commensal gut bacteria, have signaling effects on host metabolism. Oral supplementation of the essential amino acid histidine has been shown to exert metabolic benefits. To investigate whether dietary histidine aids glycemic control, we performed a case-controlled parallel clinical intervention study in participants with type 2 diabetes (T2D) and healthy controls. Participants received oral histidine for seven weeks. After 2 weeks of histidine supplementation, the microbiome was depleted by antibiotics to determine the microbial contribution to histidine metabolism. We assessed glycemic control, immunophenotyping of peripheral blood mononucelar cells (PBMC), DNA methylation of PBMCs and fecal gut microbiota composition. Histidine improves several markers of glycemic control, including postprandial glucose levels with a concordant increase in the proportion of MAIT cells after two weeks of histidine supplementation. The increase in MAIT cells was associated with changes in gut microbial pathways such as riboflavin biosynthesis and epigenetic changes in the amino acid transporter SLC7A5. Associations between the microbiome and MAIT cells were replicated in the MetaCardis cohort. We propose a conceptual framework for how oral histidine may affect MAIT cells via altered gut microbiota composition and SLC7A5 expression in MAIT cells directly and thereby influencing glycemic control. Future studies should focus on the role of flavin biosynthesis intermediates and SLC7A5 modulation in MAIT cells to modulate glycemic control.
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Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Histidina , Células T Invariantes Associadas à Mucosa , Humanos , Histidina/metabolismo , Diabetes Mellitus Tipo 2/microbiologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/imunologia , Microbioma Gastrointestinal/efeitos dos fármacos , Pessoa de Meia-Idade , Masculino , Feminino , Células T Invariantes Associadas à Mucosa/imunologia , Células T Invariantes Associadas à Mucosa/metabolismo , Controle Glicêmico , Suplementos Nutricionais , Estudos de Casos e Controles , Fezes/microbiologia , Glicemia/metabolismo , Idoso , Adulto , Bactérias/classificação , Bactérias/metabolismo , Bactérias/genética , Administração Oral , Metilação de DNARESUMO
Diet composition impacts metabolic health and is now recognized to shape the immune system, especially in the intestinal tract. Nutritional imbalance and increased caloric intake are induced by high-fat diet (HFD) in which lipids are enriched at the expense of dietary fibers. Such nutritional challenge alters glucose homeostasis as well as intestinal immunity. Here, we observed that short-term HFD induced dysbiosis, glucose intolerance and decreased intestinal RORγt+ CD4 T cells, including peripherally-induced Tregs and IL17-producing (Th17) T cells. However, supplementation of HFD-fed male mice with the fermentable dietary fiber fructooligosaccharides (FOS) was sufficient to maintain RORγt+ CD4 T cell subsets and microbial species known to induce them, alongside having a beneficial impact on glucose tolerance. FOS-mediated normalization of Th17 cells and amelioration of glucose handling required the cDC2 dendritic cell subset in HFD-fed animals, while IL-17 neutralization limited FOS impact on glucose tolerance. Overall, we uncover a pivotal role of cDC2 in the control of the immune and metabolic effects of FOS in the context of HFD feeding.
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Células Dendríticas , Dieta Hiperlipídica , Homeostase , Camundongos Endogâmicos C57BL , Oligossacarídeos , Animais , Oligossacarídeos/farmacologia , Dieta Hiperlipídica/efeitos adversos , Células Dendríticas/imunologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Masculino , Camundongos , Células Th17/imunologia , Células Th17/metabolismo , Células Th17/efeitos dos fármacos , Glucose/metabolismo , Interleucina-17/metabolismo , Fibras na Dieta/farmacologia , Intolerância à Glucose/imunologia , Intolerância à Glucose/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Disbiose/imunologia , Microbioma Gastrointestinal/efeitos dos fármacosRESUMO
This lecture delves into the pivotal role of adipose tissue in obesity and its response to weight loss, particularly via bariatric surgery. Adipose tissue, responsible for storing excess energy, undergoes significant changes during obesity, marked by inflammation and fibrosis. Bariatric surgery, serving as a model, allow the exploration of adipose tissue remodeling post-weight loss, inducing metabolic and fibro-inflammatory shifts. Despite successful weight loss, inflammation and fibrosis persist, as evidenced by changes in immune cells, altered cytokine profiles and the accumulation of extracellular matrix (ECM). Unfortunately, these lingering effects impair the normal adipose tissue function. In this context, adipose progenitors, an heterogenous resident population of mesenchymal stromal cells, display functions important to fibrosis development, capable of differentiating into myofibroblasts and contributing to ECM deposition. Particularly, a distinct subpopulation of adipose progenitors with high CD9 expression (CD9high) is associated with fibrosis and insulin resistance in human obesity. The persistence of fibrosis post-weight loss poses challenges, correlating with metabolic dysfunction despite improved glucose tolerance. A comprehensive understanding of the mechanisms driving adipose tissue remodeling and fibrosis post-weight loss is imperative for the development of effective treatments for obesity. The intricate interplay between adipose tissue, inflammation, and fibrosis underscores the necessity for further in-depth research to elucidate these mechanisms and formulate targeted therapies for obesity-related complications.
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Tecido Adiposo , Cirurgia Bariátrica , Fibrose , Obesidade , Redução de Peso , Humanos , Cirurgia Bariátrica/métodos , Tecido Adiposo/metabolismo , Obesidade/cirurgia , Obesidade/metabolismo , Redução de Peso/fisiologia , Inflamação/patologia , Resistência à Insulina/fisiologiaRESUMO
The importance of the proper localization of most receptors at the cell surface is often underestimated, although this feature is essential for optimal receptor response. Endospanin 1 (Endo1) (also known as OBRGRP or LEPROT) is a protein generated from the same gene as the human leptin receptor and regulates the trafficking of proteins to the surface, including the leptin receptor. The systemic role of Endo1 on whole-body metabolism has not been studied so far. Here, we report that general Endo1-KO mice fed a high-fat diet develop metabolically healthy obesity with lipid repartitioning in organs and preferential accumulation of fat in adipose tissue, limited systematic inflammation, and better controlled glucose homeostasis. Mechanistically, Endo1 interacts with the lipid translocase CD36, thus regulating its surface abundance and lipid uptake in adipocytes. In humans, the level of Endo1 transcripts is increased in the adipose tissue of patients with obesity, but low levels rather correlate with a profile of metabolically healthy obesity. We suggest here that Endo1, most likely by controlling CD36 cell surface abundance and lipid uptake in adipocytes, dissociates obesity from diabetes and that its absence participates in metabolically healthy obesity.
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Tecido Adiposo , Antígenos CD36 , Dieta Hiperlipídica , Camundongos Knockout , Obesidade , Animais , Feminino , Humanos , Masculino , Camundongos , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Antígenos CD36/metabolismo , Antígenos CD36/genética , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Metabolismo dos Lipídeos/genética , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Obesidade/genéticaRESUMO
Nearly 90 clinicians and researchers from around the world attended the first IMPROVE 2022 International Meeting on Pathway-Related Obesity. Delegates attended in person or online from across Europe, Argentina and Israel to hear the latest scientific and clinical developments in hyperphagia and severe, early-onset obesity, and set out a vision of excellence for the future for improving the diagnosis, treatment, and care of patients with melanocortin-4 receptor (MC4R) pathway-related obesity. The meeting co-chair Peter Kühnen, Charité Universitätsmedizin Berlin, Germany, indicated that change was needed with the rapidly increasing prevalence of obesity and the associated complications to improve the understanding of the underlying mechanisms and acknowledge that monogenic forms of obesity can play an important role, providing insights that can be applied to a wider group of patients with obesity. World-leading experts presented the latest research and led discussions on the underlying science of obesity, diagnosis (including clinical and genetic approaches such as the role of defective MC4R signalling), and emerging clinical data and research with targeted pharmacological approaches. The aim of the meeting was to agree on the questions that needed to be addressed in future research and to ensure that optimised diagnostic work-up was used with new genetic testing tools becoming available. This should aid the planning of new evidence-based treatment strategies for the future, as explained by co-chair Martin Wabitsch, Ulm University Medical Center, Germany.
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Obesidade , Receptor Tipo 4 de Melanocortina , Humanos , Hiperfagia , Obesidade/terapia , Receptor Tipo 4 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/metabolismo , Transdução de SinaisRESUMO
BACKGROUND/OBJECTIVES: Proinflammatory cytokines are increased in obese adipose tissue, including inflammasome key masters. Conversely, IL-18 protects against obesity and metabolic dysfunction. We focused on the IL-18 effect in controlling adipose tissue remodeling and metabolism. MATERIALS/SUBJECTS AND METHODS: We used C57BL/6 wild-type (WT) and interleukine-18 deficient (IL-18-/-) male mice fed a chow diet and samples from bariatric surgery patients. RESULTS: IL-18-/- mice showed increased adiposity and proinflammatory cytokine levels in adipose tissue, leading to glucose intolerance. IL-18 was widely secreted by stromal vascular fraction but not adipocytes from mice's fatty tissue. Chimeric model experiments indicated that IL-18 controls adipose tissue expansion through its presence in tissues other than bone marrow. However, IL-18 maintains glucose homeostasis when present in bone marrow cells. In humans with obesity, IL-18 expression in omental tissue was not correlated with BMI or body fat mass but negatively correlated with IRS1, GLUT-4, adiponectin, and PPARy expression. Also, the IL-18RAP receptor was negatively correlated with IL-18 expression. CONCLUSIONS: IL-18 signaling may control adipose tissue expansion and glucose metabolism, as its absence leads to spontaneous obesity and glucose intolerance in mice. We suggest that resistance to IL-18 signaling may be linked with worse glucose metabolism in humans with obesity.
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Tecido Adiposo , Interleucina-18 , Camundongos Endogâmicos C57BL , Obesidade , Animais , Interleucina-18/metabolismo , Camundongos , Masculino , Tecido Adiposo/metabolismo , Humanos , Obesidade/metabolismo , Intolerância à Glucose/metabolismo , Modelos Animais de Doenças , Camundongos KnockoutRESUMO
BACKGROUND: The determinants of early-onset obesity (< 6 years) are not completely elucidated, however eating behavior has a central role. To date no study has explored eating behavior in children with severe, early-onset obesity. Self-administered questionnaire data from these children were examined to evaluate eating behavior and the etiology of early-onset obesity. METHODS: Children with severe, early-onset obesity (body mass index [BMI] > International Obesity Task Force [IOTF] 30) of different etiologies (hypothalamic obesity [HO], intellectual disability with obesity [IDO], common polygenic obesity [CO]) were prospectively included. BMI history and responses from the Dykens' Hyperphagia Questionnaire and an in-house Impulsivity Questionnaire at first visit were compared between groups. RESULTS: This cohort of 75 children (39 girls; mean age ± standard deviation [SD] 10.8 ± 4.4 years) had severe, early-onset obesity at an age of 3.8 ± 2.7 years, with a BMI Z-score of 4.9 ± 1.5. BMI history varied between the 3 groups, with earlier severe obesity in the HO group versus 2 other groups (BMI > IOTF40 at 3.4 ± 1.6 vs. 4.6 ± 1.6 and 8.4 ± 4.1 years for the IDO and CO groups, respectively [P < 0.01]). Absence of adiposity rebound was more prevalent in the HO group (87% vs. 63% and 33% for the IDO and CO groups, respectively [P < 0.01]). The Dykens' mean total score for the cohort was 22.1 ± 7.2 with no significant between-group differences. Hyperphagia (Dykens' score > 19) and impulsivity (score > 7) were found in 50 (67%) and 11 children (15%), respectively, with no difference between the HO, IDO and CO groups regarding the number of patients with hyperphagia (10 [67%], 14 [74%], and 26 [63%] children, respectively) or impulsivity (2 [13%], 1 [7%], and 8 [19%] children, respectively). Children with food impulsivity had significantly higher total and severity scores on the Dykens' Questionnaire versus those without impulsivity. CONCLUSION: The Dykens' and Impulsivity questionnaires can help diagnose severe hyperphagia with/without food impulsivity in children with early-onset obesity, regardless of disease origin. Their systematic use can allow more targeted management of food access control in clinical practice and monitor the evolution of eating behavior in the case of innovative therapeutic targeting hyperphagia.
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Hiperfagia , Obesidade , Criança , Feminino , Humanos , Lactente , Pré-Escolar , Hiperfagia/complicações , Obesidade/etiologia , Índice de Massa Corporal , Comportamento Alimentar , Comportamento Impulsivo , Inquéritos e QuestionáriosRESUMO
Hyaluronan is an important extracellular matrix component, with poorly documented physiological role in the context of lipid-rich adipose tissue. We have investigated the global impact of hyaluronan removal from adipose tissue environment by in vitro exposure to exogenous hyaluronidase (or heat inactivated enzyme). Gene set expression analysis from RNA sequencing revealed downregulated adipogenesis as a main response to hyaluronan removal from human adipose tissue samples, which was confirmed by hyaluronidase-mediated inhibition of adipocyte differentiation in the 3T3L1 adipose cell line. Hyaluronidase exposure starting from the time of induction with the differentiation cocktail reduced lipid accumulation in mature adipocytes, limited the expression of terminal differentiation marker genes, and impaired the early induction of co-regulated Cebpa and Pparg mRNA. Reduction of Cebpa and Pparg expression by exogenous hyaluronidase was also observed in cultured primary preadipocytes from subcutaneous, visceral or brown adipose tissue of mice. Mechanistically, inhibition of adipogenesis by hyaluronan removal was not caused by changes in osmotic pressure or cell inflammatory status, could not be mimicked by exposure to threose, a metabolite generated by hyaluronan degradation, and was not linked to alteration in endogenous Wnt ligands expression. Rather, we observed that hyaluronan removal associated with disrupted primary cilia dynamics, with elongated cilium and higher proportions of preadipocytes that remained ciliated in hyaluronidase-treated conditions. Thus, our study points to a new link between ciliogenesis and hyaluronan impacting adipose tissue development.
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Cílios , Ácido Hialurônico , Camundongos , Humanos , Animais , Ácido Hialurônico/metabolismo , Cílios/metabolismo , PPAR gama/metabolismo , Hialuronoglucosaminidase/genética , Hialuronoglucosaminidase/metabolismo , Diferenciação Celular/fisiologia , Tecido Adiposo Marrom/metabolismo , LipídeosRESUMO
AIMS: Gut microbiota have been linked to blood lipid levels and cardiovascular diseases (CVDs). The composition and abundance of gut microbiota trophic networks differ between ethnicities. We aim to evaluate the relationship between gut microbiotal trophic networks and CVD phenotypes. METHODS AND RESULTS: We included cross-sectional data from 3860 individuals without CVD history from 6 ethnicities living in the Amsterdam region participating in the prospective Healthy Life in Urban Setting (HELIUS) study. Genetic variants were genotyped, faecal gut microbiota were profiled, and blood and anthropometric parameters were measured. A machine learning approach was used to assess the relationship between CVD risk (Framingham score) and gut microbiota stratified by ethnicity. Potential causal relationships between gut microbiota composition and CVD were inferred by performing two-sample Mendelian randomization with hard CVD events from the Pan-UK Biobank and microbiome genome-wide association studies summary data from a subset of the HELIUS cohort (n = 4117). Microbial taxa identified to be associated with CVD by machine learning and Mendelian randomization were often ethnic-specific, but some concordance across ethnicities was found. The microbes Akkermansia muciniphila and Ruminococcaceae UCG-002 were protective against ischaemic heart disease in African-Surinamese and Moroccans, respectively. We identified a strong inverse association between blood lipids, CVD risk, and the combined abundance of the correlated microbes Christensenellaceae-Methanobrevibacter-Ruminococcaceae (CMR). The CMR cluster was also identified in two independent cohorts and the association with triglycerides was replicated. CONCLUSION: Certain gut microbes can have a potentially causal relationship with CVD events, with possible ethnic-specific effects. We identified a trophic network centred around Christensenellaceae, Methanobrevibacter, and various Ruminococcaceae, frequently lacking in South-Asian Surinamese, to be protective against CVD risk and associated with low triglyceride levels.
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Doenças Cardiovasculares , Etnicidade , Microbioma Gastrointestinal , Humanos , Bactérias/genética , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/microbiologia , Estudos Transversais , Estudo de Associação Genômica Ampla , Lipídeos , Estudos Prospectivos , Fatores de Risco , Países BaixosRESUMO
PURPOSE OF REVIEW: Understanding the spectrum of drivers that influence the gut microbiome (GM) remains a crucial field of investigation. Among these factors, diet has received particular attention, as it could explain up to 20% of the variability in GM composition between individuals. This review focuses on the complex relationships between different dietary patterns and GM in humans, based on recent findings. RECENT FINDINGS: Current evidence underscores the multifaceted impact of diet on GM richness, diversity, and overall composition. Key contributing factors encompass dietary habits, nutritional interventions, food quality and variety, macronutrient distribution, timing of feeding, and selective exclusion of certain foods. SUMMARY: The intricate interplay between diet and GM is of fundamental importance in shaping the interaction between the host and the environment. Further understanding the causal impact of diet on GM has promising potential for the advancement of strategies to promote health and mitigate cardio-metabolic disease risks through dietary interventions. GRAPHICAL ABSTRACT: http://links.lww.com/COCN/A21.
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Dieta , Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/fisiologia , Dieta/métodos , Comportamento Alimentar/fisiologia , Interações entre Hospedeiro e Microrganismos/fisiologiaRESUMO
The study of the gut microbiome holds great promise for understanding and treating metabolic diseases, as its functions and derived metabolites can influence the metabolic status of the host. While research on the fecal microbiome has provided valuable insights, it tells us only part of the story. This limitation arises from the substantial variations in microorganism distribution throughout the gastrointestinal tract due to changes in physicochemical conditions. Thus, relying solely on the fecal microbiome may not be sufficient to draw comprehensive conclusions about metabolic diseases. The proximal part of the small intestine, particularly the jejunum, indeed, serves as the crucial site for digestion and absorption of nutrients, suggesting a potential role of its microbiome in metabolic regulation. Unfortunately, it remains relatively underexplored due to limited accessibility. This review presents current evidence regarding the relationships between the microbiome in the upper small intestine and various phenotypes, focusing on obesity and type 2 diabetes, in both humans and rodents. Research on humans is still limited with variability in the population and methods used. Accordingly, to better understand the role of the whole gut microbiome in metabolic diseases, studies exploring the human microbiome in different niches are needed.
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Diabetes Mellitus Tipo 2 , Doenças Metabólicas , Microbiota , Humanos , Doenças Metabólicas/metabolismo , Obesidade/terapia , Intestino Delgado/metabolismoRESUMO
The gut microbiome plays a significant role in the development of Type 2 Diabetes Mellitus (T2DM), but the functional mechanisms behind this association merit deeper investigation. Here, we used the nanopore sequencing technology for metagenomic analyses to compare the gut microbiome of individuals with T2DM from the United Arab Emirates (n = 40) with that of control (n = 44). DMM enterotyping of the cohort resulted concordantly with previous results, in three dominant groups Bacteroides (K1), Firmicutes (K2), and Prevotella (K3) lineages. The diversity analysis revealed a high level of diversity in the Firmicutes group (K2) both in terms of species richness and evenness (Wilcoxon rank-sum test, p value < 0.05 vs. K1 and K3 groups), consistent with the Ruminococcus enterotype described in Western populations. Additionally, functional enrichment analyses of KEGG modules showed significant differences in abundance between individuals with T2DM and controls (FDR < 0.05). These differences include modules associated with the degradation of amino acids, such as arginine, the degradation of urea as well as those associated with homoacetogenesis. Prediction analysis with the Predomics approach suggested potential biomarkers for T2DM, including a balance between a depletion of Enterococcus faecium and Blautia lineages with an enrichment of Absiella spp or Eubacterium limosum in T2DM individuals, highlighting the potential of metagenomic analysis in predicting predisposition to diabetic cardiomyopathy in T2DM patients.
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Diabetes Mellitus Tipo 2 , Cardiomiopatias Diabéticas , Microbioma Gastrointestinal , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Microbioma Gastrointestinal/genética , Firmicutes , MetagenomaRESUMO
INTRODUCTION: Obesity is associated with low-grade inflammation, including intestinal inflammation based on fecal or serum calprotectin (FC-SC) measurement. Roux-en-Y gastric bypass (RYGB) improves obesity-related parameters. However, the association between FC-SC levels and postoperative course and the link with metabolic and inflammatory phenotypes before and after RYGB remains unclear. METHODS: We determined SC levels in 48 patients before (T0) and 6 months after (T6M) RYGB. We then analyzed postoperative changes in FC-SC levels and the relationship with inflammation and metabolic status. RESULTS: Twenty-three patients (48%) had elevated SC levels (Ë2.9 µg/mL) at T0 and T6M. Six of 29 patients (20.7%) had elevated FC concentrations (>50 µg/g) at T0 vs. 16 of 17 patients (94.1%) at T6M (p=0.006). At T0, FC levels correlated with BMI (Rho=0.63; p=0.001) and systemic inflammation (CRP: Rho=0.66, p=0.0006; IL-6: Rho=0.48, p=0.03; haptoglobin: Rho=0.75; p= 0.0006). SC tended to be positively associated with triglyceride levels (Rho=0.34; p=0.08), BMI (Rho=0.34; p=0.08), and inflammatory markers (CRP: Rho=0.33; p=0.09; IL-6: Rho=0.36; p=0.06). FC levels were associated with increased jejunal IL-17+CD8+ T-cell densities (Rho:0.90; p=0.0002). FC and SC were correlated together at T0 (Rho=0.83; p<0.001) but not at T6M. At T6M, SC decreased by 53.6%, whereas FC increased by 79.7%. SC and FC were not associated with any of the variables studied at T6M. CONCLUSION: FC is a surrogate marker of systemic and intestinal inflammation and adiposity, whereas SC only tends to correlate with systemic inflammation. At 6 months after RYGB, SC-based systemic inflammation decreased, whereas FC-based intestinal inflammation increased. FC and SC levels follow different trajectories and are unrelated to improvements following bariatric surgery.
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Derivação Gástrica , Obesidade Mórbida , Humanos , Obesidade Mórbida/cirurgia , Complexo Antígeno L1 Leucocitário , Estudos Prospectivos , Interleucina-6 , Obesidade/cirurgia , InflamaçãoRESUMO
The melanocortin-4 receptor agonist setmelanotide is now recommended for the treatment of genetic obesity due to proopiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1), or leptin receptor (LEPR) deficiency in patients aged 6 years and older. Here, we describe the clinical benefit of setmelanotide administration in a 5-year-old child with severe hyperphagia and obesity due to POMC deficiency. Daily administration of 0.5â mg setmelanotide for 12 months resulted in significant weight loss of -30â kg from baseline (-36% of weight loss) and improvements in hyperphagia and metabolic status. No major side effects were observed, except for hyperpigmentation and transient spontaneous erections. Interestingly, the clinical improvement of the child was associated with a remarkable improvement in the quality of life of the parents, along with a decrease in their emotional scores. This observation supports the early use of setmelanotide in young children with melanocortin pathway variants, in order to limit the adverse consequences of early and extreme weight gain, and to improve the quality of life of patients and of their relatives.
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We previously reported that autologous-fecal-microbiota-transplantation (aFMT), following 6 m of lifestyle intervention, attenuated subsequent weight regain and insulin rebound for participants consuming a high-polyphenol green-Mediterranean diet. Here, we explored whether specific changes in the core (abundant) vs. non-core (low-abundance) gut microbiome taxa fractions during the weight-loss phase (0-6 m) were differentially associated with weight maintenance following aFMT. Eighty-two abdominally obese/dyslipidemic participants (age = 52 years; 6 m weightloss = -8.3 kg) who provided fecal samples (0 m, 6 m) were included. Frozen 6 m's fecal samples were processed into 1 g, opaque and odorless aFMT capsules. Participants were randomly assigned to receive 100 capsules containing their own fecal microbiota or placebo over 8 m-14 m in ten administrations (adherence rate > 90%). Gut microbiome composition was evaluated using shotgun metagenomic sequencing. Non-core taxa were defined as ≤ 66% prevalence across participants. Overall, 450 species were analyzed. At baseline, 13.3% were classified as core, and Firmicutes presented the highest core proportion by phylum. During 6 m weight-loss phase, abundance of non-core species changed more than core species (P < .0001). Subject-specific changes in core and non-core taxa fractions were strongly correlated (Jaccard Index; r = 0.54; P < .001). Following aFMT treatment, only participants with a low 6 m change in core taxa, and a high change in non-core taxa, avoided 8-14 m weight regain (aFMT = -0.58 ± 2.4 kg, corresponding placebo group = 3.18 ± 3.5 kg; P = .02). In a linear regression model, low core/high non-core 6 m change was the only combination that was significantly associated with attenuated 8-14 m weight regain (P = .038; P = .002 for taxa patterns/treatment intervention interaction). High change in non-core, low-abundance taxa during weight-loss might mediate aFMT treatment success for weight loss maintenance.ClinicalTrials.gov: NCT03020186.
Assuntos
Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Humanos , Pessoa de Meia-Idade , Fezes , Redução de Peso , Aumento de PesoRESUMO
The host-microbiota co-metabolite trimethylamine N-oxide (TMAO) is linked to increased cardiovascular risk but how its circulating levels are regulated remains unclear. We applied "explainable" machine learning, univariate, multivariate and mediation analyses of fasting plasma TMAO concentration and a multitude of phenotypes in 1,741 adult Europeans of the MetaCardis study. Here we show that next to age, kidney function is the primary variable predicting circulating TMAO, with microbiota composition and diet playing minor, albeit significant, roles. Mediation analysis suggests a causal relationship between TMAO and kidney function that we corroborate in preclinical models where TMAO exposure increases kidney scarring. Consistent with our findings, patients receiving glucose-lowering drugs with reno-protective properties have significantly lower circulating TMAO when compared to propensity-score matched control individuals. Our analyses uncover a bidirectional relationship between kidney function and TMAO that can potentially be modified by reno-protective anti-diabetic drugs and suggest a clinically actionable intervention for decreasing TMAO-associated excess cardiovascular risk.
Assuntos
Endocrinologia , Metilaminas , Adulto , Humanos , Causalidade , RimRESUMO
INTRODUCTION: Sleeve gastrectomy (SG) is a popular surgical weight-loss procedure, but there are increasing reports of revisional Roux-Y-gastric-bypass (R-RYGB) to manage weight-loss failure (WLF) or proton pump inhibitor (PPI)-refractory gastroesophageal reflux disease (GERD) after SG, with little data available in these settings. METHODS: This retrospective study included all consecutive patients undergoing R-RYGB for WLF or RGERD after SG in two bariatric care centers from 2012 to 2018. RESULTS: Of 720 patients, 46 (3.6%) underwent R-RYGB (RGERD, n = 25; 54.4%; WLF, n = 21; 45.6%) within 44.8 ± 27.5 months post-SG. SG had enabled 27% ± 11.6 total weight loss (TWL) in the RGERD group vs. 7.2% ± 12.5% TWL in the WLF group (p < 0.001). At R-RYGB, WLF-group patients had a higher BMI (47.8 ± 8.4 vs. 34.7 ± 6.1 kg/m2; p < 0.001) and a higher number of comorbidities (2.4 ± 1.5 vs 1.5 ± 1.2; p < 0.02) compared to RGERD-group patients, while severe morbidity (Clavien-Dindo ≥ IIIb) was not significantly different between groups (6.5% vs 2.1%, p = 0.6). %TWL was still higher in the RGERD group at 12 months post-R-RYGB (35.6% ± 10.4 vs. 23.8% ± 9.2; p < 0.01) but not after 24 months post-R-RYGB. R-RYGB corrected reflux symptoms in 32 (94%) patients and reduced PPI use in 29 (97%) patients (p < 0.001), with no significant between-group difference. A history of adjustable gastric banding (AGB) (N = 8;17.4%) prior to SG was associated with a similar prevalence of GERD at R-RYGB and a lower %TWL (AGB:13.1 ± 10.2 vs. No AGB:31.6 ± 8.5; p < 0.05) at 3 years post-R-RYGB. CONCLUSION: R-RYGB following SG provides remission of reflux symptoms in 94% of patients and extra weight loss in patients with WLF, except in patients with a history of AGB prior to SG.