Circulating miRNAs as Biomarkers of Subclinical Atherosclerosis associated to Severe Obesity before and after Bariatric Surgery.

INTRODUCTION: severe obesity results in high cardiovascular risk, increasing morbidity and mortality. New and improved methods are needed to detect cardiovascular diseases rapidly in severe obesity. microRNAs (miRNAs) has shown promise as diagnostic tools. This study aimed to identify plasma miRNAs useful as biomarkers of cardiovascular risk (CVR) in people with severe obesity. METHODS: The study included 66 people with severe obesity classified in groups with atheroma (n = 32) and free of plaques (n = 34). Plasma samples were collected 1 month before bariatric surgery and at 6 and 12 months of follow-up. Participants were screened for the levels of 188 miRNAs, and 24 promising candidates were individually validated by quantitative polymerase chain reaction. RESULTS: After validation, 5 of the 24 miRNAs showed significant differences over time in both groups: miR-375 increased after bariatric surgery, whereas miR-144-5p, miR-20a-3p, miR-145-5p and miR-21-3p exhibited decreased expression after bariatric surgery. The expression of 3 of the 24 miRNAs also differed between patients with and without atheroma: subjects with plaque had lower miR-126 but higher miR-21-3p and miR-133a-3p. Only miR-133a-3p exhibited exceptional discriminatory ability between subjects with and without plaque (area under the curve, 0.90; 95% confidence interval, 0.81-0.99). CONCLUSION: A specific signature of c-miRNA comprising miR-375, miR-144-5p, miR-20a-3p, miR-145-5p and miR-21-3p may facilitate CVR monitoring after bariatric surgery. Furthermore, miR-21-3p, miR-126-3p and miR-133a-3p show potential as specific biomarkers for subclinical atherosclerosis, with miR-133a-3p potentially able to diagnose subclinical atherosclerosis early in severe obesity.

Metabolome biomarkers linking dietary fibre intake with cardiometabolic effects: results from the Danish Diet, Cancer and Health-Next Generations MAX study.

Biomarkers associated with dietary fibre intake, as complements to traditional dietary assessment tools, may improve the understanding of its role in human health. Our aim was to discover metabolite biomarkers related to dietary fibre intake and investigate their association with cardiometabolic risk factors. We used data and samples from the Danish Diet Cancer and Health Next Generation (DCH-NG) MAX-study, a one-year observational study with evaluations at baseline, six and 12 months (n = 624, 55% female, mean age: 43 years, 1353 observations). Direct associations between fibre intake and plasma concentrations of 2,6-dihydroxybenzoic acid (2,6-DHBA) and indolepropionic acid were observed at the three time-points. Both metabolites showed an intraclass-correlation coefficient (ICC) > 0.50 and were associated with the self-reported intake of wholegrain cereals, and of fruits and vegetables, respectively. Other metabolites associated with dietary fibre intake were linolenoyl carnitine, 2-aminophenol, 3,4-DHBA, and proline betaine. Based on the metabolites associated with dietary fibre intake we calculated predicted values of fibre intake using a multivariate, machine-learning algorithm. Metabolomics-based predicted fibre, but not self-reported fibre values, showed negative associations with cardiometabolic risk factors (i.e. high sensitivity C-reactive protein, systolic and diastolic blood pressure, all FDR-adjusted p-values <0.05). Furthermore, different correlations with gut microbiota composition were observed. In conclusion, 2,6-DHBA and indolepropionic acid in plasma may better link dietary fibre intake with its metabolic effects than self-reported values. These metabolites may represent a novel class of biomarkers reflecting both dietary exposure and host and/or gut microbiota characteristics providing a read-out that is differentially related to cardiometabolic risk.

Irisin as a Novel Biomarker of Subclinical Atherosclerosis in Severe Obesity.

Severe obesity (SO) can accelerate atherosclerosis and the onset of acute cardiovascular events. The diagnosis of atherosclerosis in the context of a high body mass index (BMI) can be challenging, making the identification of biomarkers clinically relevant. We aimed to assess the usefulness of irisin as a biomarker for subclinical atherosclerosis in participants with SO. This prospective observational study included 61 participants undergoing bariatric surgery for SO, defined as a BMI >40 kg/m2 or >35 kg/m2 with at least one comorbidity. Atherosclerotic plaques were detected by ultrasound. Plasma samples were obtained 1 month before and at 6 and 12 months after bariatric surgery to measure irisin by ELISA. Additionally, subcutaneous samples of adipose tissue were taken and genotyped to identify irisin polymorphism rs3480. Irisin levels were positively correlated with BMI (r = 0.23, p = 0.0064), negatively correlated with atheroma-related parameters (e.g., carotid intima-media thickness), and lower in subjects with atheroma (p < 0.0002). Irisin also showed good overall accuracy for discriminating plaque presence (AUC, 0.81; 95% CI, 0.6956-0.9156). However, the rs3480 polymorphism correlated with neither the irisin levels nor the presence of atheromas. Iirisin could identify subclinical atherosclerosis in SO and might facilitate clinical diagnosis.

Dietary Sources of Anthocyanins and Their Association with Metabolome Biomarkers and Cardiometabolic Risk Factors in an Observational Study.

Anthocyanins (ACNs) are (poly)phenols associated with reduced cardiometabolic risk. Associations between dietary intake, microbial metabolism, and cardiometabolic health benefits of ACNs have not been fully characterized. Our aims were to study the association between ACN intake, considering its dietary sources, and plasma metabolites, and to relate them with cardiometabolic risk factors in an observational study. A total of 1351 samples from 624 participants (55% female, mean age: 45 ± 12 years old) enrolled in the DCH-NG MAX study were studied using a targeted metabolomic analysis. Twenty-four-hour dietary recalls were used to collect dietary data at baseline, six, and twelve months. ACN content of foods was calculated using Phenol Explorer and foods were categorized into food groups. The median intake of total ACNs was 1.6mg/day. Using mixed graphical models, ACNs from different foods showed specific associations with plasma metabolome biomarkers. Combining these results with censored regression analysis, metabolites associated with ACNs intake were: salsolinol sulfate, 4-methylcatechol sulfate, linoleoyl carnitine, 3,4-dihydroxyphenylacetic acid, and one valerolactone. Salsolinol sulfate and 4-methylcatechol sulfate, both related to the intake of ACNs mainly from berries, were inversely associated with visceral adipose tissue. In conclusion, plasma metabolome biomarkers of dietary ACNs depended on the dietary source and some of them, such as salsolinol sulfate and 4-methylcatechol sulfate may link berry intake with cardiometabolic health benefits.

A mixture of four dietary fibres ameliorates adiposity and improves metabolic profile and intestinal health in cafeteria-fed obese rats: an integrative multi-omics approach.

The aim of this study was to assess the effects of a mixture of four dietary fibers on obese rats. Four groups of male Wistar rats were fed with either standard chow (STD) or cafeteria diet (CAF) and were orally supplemented with either fibre mixture (2 g kg-1 of body weight) (STD+F or CAF+F groups) or vehicle (STD+VH or CAF+VH groups). We studied a wide number of biometric, biochemical, transcriptomic, metagenomic and metabolomic variables and applied an integrative multivariate approach based on multiple factor analysis and Pearson's correlation analysis. A significant reduction in body weight, adiposity, HbA1c and HDL-cholesterol serum levels, and colon MPO activity was observed, whereas cecal weight and small intestine length:weight ratio were significantly increased in F-treated groups compared to control animals. CAF+F rats displayed a significant enhancement in energy expenditure, fat oxidation and fresh stool weight, and a significant reduction in adiponectin and LPS serum levels, compared to control group. Animals in STD+F group showed reduced serum LDL-cholesterol levels and a significant reduction in total cholesterol levels in the liver compared to STF+VH group. The intervention effect was reflected at the metabolomic (i.e., production of short-chain fatty acids, phenolic acids, and amino acids), metagenomic (i.e., modulation of Ruminococcus and Lactobacillus genus) and transcriptomic (i.e., expression of tight junctions and proteolysis) levels. Altogether, our integrative multi-omics approach highlights the potential of supplementation with a mixture of fibers to ameliorate the impairments triggered by obesity in terms of adiposity, metabolic profile, and intestinal health.

Mortality in Elderly Patients Taking Furosemide: Prospective Cohorts Study.

Objectives: Low blood pressure (BP) has been proposed as a risk factor of death in elderly patients. However, this association could be partially accounted for by the deleterious effects of BP-lowering drugs. We analyzed whether these drugs are associated to an increased risk of death in elderly patients taking multiple potential confounders into account. Design: This is a prospective cohort study. Setting and Participants. Probabilistic sample of 772 community-dwelling patients aged >65 years living in Spain, who were appointed for an initial clinical visit and followed up through telephone calls 4, 6, 9, 12, and 60 months afterwards. Methods: At baseline visit, BP was measured using standardized methods, and BP medications and risk factors of death in elderly patients (BMI, oxygen saturation, toxic habits, comorbidity, muscular strength, and functional and cognitive capacity) were collected. During the follow-up, the vital status of patients and the date of death were ascertained. Results: During a median 5-year follow-up, 226 all-cause deaths occurred among the 686 participants included in the analysis. In a Cox regression model that included all the BP drug classes, diuretics and nitrites were significantly associated with mortality (p < 0.005). Within diuretics, furosemide was found to be responsible for the association of the group. In multivariable Cox regression models adjusted for BP and the rest of the mortality risk factors, furosemide remained as the only BP drug that was independently associated with mortality (hazard ratio 2.34; p < 0.01). Conclusions: Furosemide was prospectively associated with increased mortality in older people. If confirmed, this drug should be taken into account by prescribers and considered a confounder in BP studies.

The relevance of urolithins-based metabotyping for assessing the effects of a polyphenol-rich dietary intervention on intestinal permeability: A post-hoc analysis of the MaPLE trial.

A polyphenol-rich diet reduced intestinal permeability (IP) in older adults. Our aim was to evaluate if participants categorized according to urolithin metabotypes (UMs) exhibited different responses in the MaPLE trial. Fifty-one older adults (mean age: 78 years) completed an 8-week randomized-controlled-crossover trial comparing the effects of a polyphenol-rich vs. a control diet on IP, assessed through zonulin levels. Plasma and urinary metabolomics were evaluated with a semi-targeted UHPLC-MS/MS method. Gut microbiota was characterized by 16S rRNA gene profiling. UMs were determined according to urolithin excretion in 24 h urine samples. Multivariate statistics were used to characterize the differences in metabolomic and metataxonomic responses across UMs. Thirty-three participants were classified as urolithin metabotype A (UMA), 13 as urolithin metabotype B (UMB), and 5 as urolithin metabotype 0 (UM0) according to their urinary excretion of urolithins. Clinical, dietary, and biochemical characteristics at baseline were similar between UMs (all p > 0.05). After the polyphenol-rich diet, UMB vs. UMA participants showed a 2-fold higher improvement of zonulin levels (p for interaction = 0.033). Moreover, UMB vs. UMA participants were characterized for alterations in fatty acid metabolism, kynurenine pathway of tryptophan catabolism, and microbial metabolization of phenolic acids. These changes were correlated with the reduction of zonulin levels and modifications of gut microbes (increased Clostridiales, including, R. lactaris, and G. formicilis). In conclusion, urolithin-based metabotyping identified older adults with a higher improvement of IP after a polyphenol-rich diet. Our results reinforce the concept that UMs may contribute to tailor personalized nutrition interventions.

A Polyphenol-Rich Diet Increases the Gut Microbiota Metabolite Indole 3-Propionic Acid in Older Adults with Preserved Kidney Function.

SCOPE: Dietary polyphenols can alter the gut microbiota (GM) and promote the production of bioactive metabolites. Several indoles result of GM metabolism of dietary tryptophan have been associated with intestinal barrier integrity. Our aim is to study the changes in GM-derived indoles during a polyphenol-rich (PR) diet intervention in older adults. METHODS AND RESULTS: Randomized, controlled, crossover trial in adults ≥ 60 years living in a residential care facility during an 8-week PR versus control diet (n = 51). Seven GM-tryptophan metabolites are measured in serum, and metataxonomic analysis of GM is performed on fecal samples. Exploratory subgroup analyses are performed based on renal function (RF). The PR-diet significantly increases serum indole 3-propionic acid (IPA) in subjects with normal RF, but not in subjects with impaired RF. Other GM-tryptophan metabolites are not affected. Comparison of baseline GM composition shows shifts in Bacteroidales order members as well as higher abundance of Clostridiales in participants with normal RF. During the trial, variations of IPA are associated with changes in C-reactive protein (ß = 0.32, p = 0.010) and GM, particularly with the Clostridiales (r = 0.35, p < 0.001) and Enterobacteriales (r = -0.15, p < 0.05) orders. CONCLUSION: A PR diet increases the serum concentration of IPA in older adults with normal RF. Our findings may be important when defining appropriate dietary interventions for older adults. TRIAL REGISTRATION NUMBER: ISRCTN10214981 (https://doi.org/10.1186/ISRCTN10214981).

COVID-19: Clinical Presentation and Prognostic Factors of Severe Disease and Mortality in the Oldest-Old Population: A Cohort Study.

INTRODUCTION: The oldest-old population (80 years or older) has the highest lethality from COVID-19. There is little information on the clinical presentation and specific prognostic factors for this group. This trial evaluated the clinical presentation and prognostic factors of severe disease and mortality in the oldest-old population. METHODS: This is an ambispective cohort study of oldest-old patients hospitalized for respiratory infection associated with COVID-19 and with a positive test by RT-PCR. The clinical presentation and the factors associated with severe disease and mortality were evaluated (logistic regression). All patients were followed up until discharge or death. RESULTS: A total of 103 patients (59.2% female) were included. The most frequent symptoms were fever (68.9%), dyspnoea (60.2%), and cough (39.8%), and 11.7% presented confusion. Fifty-nine patients (57.3%) presented severe disease, and 59 died, with 43 patients (41.7%) presenting both of these. In the multivariate analysis, female sex (odds ratio [OR] 0.31, 95% confidence interval [95% CI] 0.13-0.73, p 0.0074) and serum lactate dehydrogenase (LDH) (OR 2.55, 95% CI 1.21-5.37, p 0.0139) were associated with severe disease, and serum sodium was associated with mortality (OR 3.12, 95% CI 1.18-8.26, p 0.0222). No chronic disease or pharmacological treatment was associated with worse outcomes. CONCLUSIONS: The typical presenting symptoms of respiratory infection in COVID-19 are less frequent in the oldest-old population. Male sex and LDH level are associated with severe disease, and the serum sodium level is associated with mortality in this population.

Crosstalk among intestinal barrier, gut microbiota and serum metabolome after a polyphenol-rich diet in older subjects with "leaky gut": The MaPLE trial.

BACKGROUND &AIM: The MaPLE study was a randomized, controlled, crossover trial involving adults ≥60 y.o. (n = 51) living in a residential care facility during an 8-week polyphenol-rich (PR)-diet. Results from the MaPLE trial showed that the PR-diet reduced the intestinal permeability (IP) in older adults by inducing changes to gut microbiota (GM). The present work aimed at studying the changes in serum metabolome in the MaPLE trial, as a further necessary step to depict the complex crosstalk between dietary polyphenols, GM, and intestinal barrier. METHODS: Serum metabolome was monitored using a semi-targeted UHPLC-MS/MS analysis. Metataxonomic analysis (16S rRNA gene profiling) of GM was performed on faecal samples. Clinical characteristics and serum levels of the IP marker zonulin were linked to GM and metabolomics data in a multi-omics network. RESULTS: Compared to the control diet, the PR-diet increased serum metabolites related to polyphenols and methylxanthine intake. Theobromine and methylxanthines, derived from cocoa and/or green tea, were positively correlated with butyrate-producing bacteria (the order Clostridiales and the genera Roseburia, Butyricicoccus and Faecalibacterium) and inversely with zonulin. A direct correlation between polyphenol metabolites hydroxyphenylpropionic acid-sulfate, 2-methylpyrogallol-sulfate and catechol-sulfate with Butyricicoccus was also observed, while hydroxyphenylpropionic acid-sulfate and 2-methylpyrogallol-sulfate negatively correlated with Methanobrevibacter. The multi-omics network indicated that participant's age, baseline zonulin levels, and changes in Porphyromonadaceae abundance were the main factors driving the effects of a PR-diet on zonulin. CONCLUSION: Overall, these results reveal the complex relationships among polyphenols consumption, intestinal permeability, and GM composition in older adults, and they may be important when setting personalized dietary interventions for older adults. TRIAL REGISTRATION NUMBER: ISRCTN10214981.