Publications by authors named "Albert Groen"

Imidazole Propionate (ImP), a gut-derived metabolite from histidine, affects insulin signaling in mice and is elevated in type 2 diabetes (T2D). However, the source of histidine and the role of the gut microbiota remain unclear. We conducted an intervention study in mice and humans, comparing ImP kinetics in mice on a high-fat diet with varying histidine levels and antibiotics, and assessed ImP levels in healthy and T2D subjects with histidine supplementation.

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  • The trans intestinal cholesterol excretion (TICE) pathway is a strategy to lower LDL cholesterol by promoting the direct excretion of cholesterol from enterocytes into feces, which was previously stimulated in mice using hydrophilic bile acids.* -
  • A clinical trial tested whether the bile acid ursodeoxycholic acid (UDCA) could increase fecal cholesterol excretion in humans, involving 20 male participants who received either UDCA or a placebo after a run-in with ezetimibe.* -
  • Results showed that while UDCA did increase the hydrophilicity of bile acids, it did not elevate fecal neutral sterols nor decrease LDL cholesterol levels, indicating TICE may not be influenced by bile acid hydroph
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Background And Objective: Patients who underwent Roux-en-Y Gastric Bypass surgery for treatment of obesity or diabetes can suffer from post-bariatric hypoglycemia (PBH). It has been assumed that PBH is caused by increased levels of the hormone GLP-1. In this research, we elucidate the role of GLP-1 in PBH with a physiology-based mathematical model.

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Background And Aims: Gallstone disease (GSD) associates with significant morbidity and mortality. Decreased secretion of bile acids has been suggested as a driving factor for GSD. Recently, we linked the protein phosphatase 1 regulatory subunit 3 beta ( rs4240624 genotype to decreased bile acid levels in bile.

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Aims/hypothesis: Post-bariatric hypoglycemia (PBH) is caused by postprandial hyperinsulinemia, due to anatomical alterations and changes in post-prandial metabolism after bariatric surgery. The mechanisms underlying the failing regulatory and compensatory systems are unclear. In this study, we investigated the differences in post-prandial hormones and metabolic profiles between patients with and without PBH.

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  • - This study tested the effects of a 14-day L2-7 supplement on blood sugar levels in 25 White Dutch men with type 2 diabetes who were already taking metformin.
  • - Results showed that the supplement significantly reduced variations in blood sugar levels and improved blood pressure compared to a placebo, but did not significantly change levels of short-chain fatty acids or bile acids.
  • - While the L2-7 supplement was well-tolerated and effective, the authors suggest that more studies with larger and more diverse groups are needed to confirm these findings.
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Background: Bariatric surgery is an effective treatment option for obesity and provides long-term weight loss and positive effects on metabolism, but the underlying mechanisms are poorly understood. Alterations in bile acid metabolism have been suggested as a potential contributing factor, but comprehensive studies in humans are lacking.

Methods: In this study, we analysed the postprandial responses of bile acids, C4 and FGF19 in plasma, and excretion of bile acids in faeces, before and after bariatric surgery in patients (n = 38; 74% females) with obesity with or without type 2 diabetes from the BARIA cohort.

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Background And Aims: Bile acids (BA) are vital regulators of metabolism. BAs are AQ6 secreted in the small intestine, reabsorbed, and transported back to the liver, where they can modulate metabolic functions. There is a paucity of data regarding the portal BA composition in humans.

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Context/objective: In order to better understand which metabolic differences are related to insulin resistance in metabolic syndrome (MetSyn), we used hyperinsulinemic-euglycemic (HE) clamps in individuals with MetSyn and related peripheral insulin resistance to circulating biomarkers.

Design/methods: In this cross-sectional study, HE-clamps were performed in treatment-naive men (n = 97) with MetSyn. Subjects were defined as insulin-resistant based on the rate of disappearance (Rd).

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Background: Bile acids play vital roles in control of lipid-, glucose-, and energy metabolism by activating Takeda G protein-coupled receptor 5 (TGR5) and Farnesoid X receptor (FXR), the latter promoting production of the endocrine-acting fibroblast growth factor 19 (FGF19). Short-term administration of single bile acids has been reported to enhance plasma levels of GLP-1 and to enhance energy expenditure. However, prolonged bile acid supplementation, e.

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The manifestation of metabolic deteriorations that accompany overweight and obesity can differ greatly between individuals, giving rise to a highly heterogeneous population. This inter-individual variation can impede both the provision and assessment of nutritional interventions as multiple aspects of metabolic health should be considered at once. Here, we apply the Mixed Meal Model, a physiology-based computational model, to characterize an individual's metabolic health A population of 342 personalized models were generated using data for individuals with overweight and obesity from three independent intervention studies, demonstrating a strong relationship between the model-derived metric of insulin resistance (ρ = 0.

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  • Gut microbiota may influence blood lipid levels and cardiovascular disease (CVD) risk, with differences observed among various ethnic groups.
  • A study involving 3,860 participants without CVD history showed that specific gut microbes were linked to CVD phenotypes, often varying by ethnicity, using machine learning and Mendelian randomization methods.
  • Key findings include protective microbes like Akkermansia muciniphila associated with ischaemic heart disease in certain ethnicities and a significant inverse relationship between blood lipids and the abundance of a microbial cluster named CMR.
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Background: Oxidized phospholipids play a key role in the atherogenic potential of lipoprotein(a) (Lp[a]); however, Lp(a) is a complex particle that warrants research into additional proinflammatory mediators. We hypothesized that additional Lp(a)-associated lipids contribute to the atherogenicity of Lp(a).

Methods: Untargeted lipidomics was performed on plasma and isolated lipoprotein fractions.

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  • Major advances in heart failure treatment haven't significantly reduced mortality, indicating that current therapies might be missing key biological pathways.
  • A study integrated genetic and molecular data from over 2,500 heart failure patients to identify critical pathways linked to mortality, validating the results with a separate group of nearly 1,800 patients.
  • Four major pathways associated with higher death rates were found: PI3K/Akt, MAPK, Ras signaling, and resistance to epidermal growth factor inhibitor, which are linked to reduced activation of the protective ERBB2 receptor influenced by neuregulin.
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High-protein diets are promoted for individuals with type 2 diabetes (T2D). However, effects of dietary protein interventions on (gut-derived) metabolites in T2D remains understudied. We therefore performed a multi-center, randomized-controlled, isocaloric protein intervention with 151 participants following either 12-week high-protein (HP; 30Energy %, N = 78) vs.

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Dyslipidemia in obesity results from excessive production and impaired clearance of triglyceride-rich (TG-rich) lipoproteins, which are particularly pronounced in the postprandial state. Here, we investigated the impact of Roux-en-Y gastric bypass (RYGB) surgery on postprandial VLDL1 and VLDL2 apoB and TG kinetics and their relationship with insulin-responsiveness indices. Morbidly obese patients without diabetes who were scheduled for RYGB surgery (n = 24) underwent a lipoprotein kinetics study during a mixed-meal test and a hyperinsulinemic-euglycemic clamp study before the surgery and 1 year later.

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Unlabelled: Diet modulates the development of insulin resistance during aging. This includes tissue-specific alterations in insulin signaling and mitochondrial function, which ultimately affect glucose homeostasis. Exercise stimulates glucose clearance and mitochondrial lipid oxidation and also enhances insulin sensitivity (IS).

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Diet modulates the development of insulin resistance during aging. This includes tissue-specific alterations in insulin signaling and mitochondrial function, which ultimately affect glucose homeostasis. Exercise stimulates glucose clearance, mitochondrial lipid oxidation and enhances insulin sensitivity.

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Weight loss through bariatric surgery is efficient for treatment or prevention of obesity related diseases such as type 2 diabetes and cardiovascular disease. Long term weight loss response does, however, vary among patients undergoing surgery. Thus, it is difficult to identify predictive markers while most obese individuals have one or more comorbidities.

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Emerging studies in the literature describe an association between high-fat, low-carbohydrate diets and severe hypercholesterolemia consistent with the levels observed in patients with (homozygous) familial hypercholesterolemia (FH). High levels of low-density lipoprotein cholesterol (LDL-C) may result from the reduced clearance of LDL particles from the circulation, the increased production of their precursor, or a combination of both. The increased intake of (saturated) fat and cholesterol, combined with limited to no intake of carbohydrates and fiber, are the main features of diets linked to hypercholesterolemia.

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Within the human population, considerable variability exists between individuals in their susceptibility to develop obesity and dyslipidemia. In humans, this is thought to be caused by both genetic and environmental variation. APOE*3-Leiden.

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To test the hypothesis that the gut microbiota of individuals with nonalcoholic fatty liver disease (NAFLD) produce enough ethanol to be a driving force in the development and progression of this complex disease, we performed one prospective clinical study and one intervention study. Ethanol was measured while fasting and 120 min after a mixed meal test (MMT) in 146 individuals. In a subset of 37 individuals and in an external validation cohort, ethanol was measured in portal vein blood.

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BACKGROUNDCytochrome P450 family 8 subfamily B member 1 (CYP8B1) generates 12α-hydroxylated bile acids (BAs) that are associated with insulin resistance in humans.METHODSTo determine whether reduced CYP8B1 activity improves insulin sensitivity, we sequenced CYP8B1 in individuals without diabetes and identified carriers of complete loss-of-function (CLOF) mutations utilizing functional assays.RESULTSMutation carriers had lower plasma 12α-hydroxylated/non-12α-hydroxylated BA and cholic acid (CA)/chenodeoxycholic acid (CDCA) ratios compared with age-, sex-, and BMI-matched controls.

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Article Synopsis
  • Previous studies showed a link between gut microbiome composition and the human genome, but the impact of ethnicity on this relationship was largely unexplored.
  • A large study of a multiethnic cohort (HELIUS) and a Mendelian randomization analysis using the Pan-UK Biobank revealed ethnicity-specific associations between host genomes and gut microbiota.
  • The findings suggest that certain gut microbes are linked to genetic factors across ethnicities and can influence cardiometabolic health traits like BMI, cholesterol, and blood pressure.
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Non-alcoholic fatty liver disease (NAFLD) is now the most frequent global chronic liver disease. Individuals with NAFLD exhibited an increased risk of all-cause mortality driven by extrahepatic cancers and liver and cardiovascular disease. Once the disease is established, women have a higher risk of disease progression and worse outcome.

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