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International Journal of Molecular... Jun 2024Consumption of a high-fat diet (HFD) has been suggested as a contributing factor behind increased intestinal permeability in obesity, leading to increased plasma levels...
Consumption of a high-fat diet (HFD) has been suggested as a contributing factor behind increased intestinal permeability in obesity, leading to increased plasma levels of microbial endotoxins and, thereby, increased systemic inflammation. We and others have shown that HFD can induce jejunal expression of the ketogenic rate-limiting enzyme mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase (HMGCS). HMGCS is activated via the free fatty acid binding nuclear receptor PPAR-α, and it is a key enzyme in ketone body synthesis that was earlier believed to be expressed exclusively in the liver. The function of intestinal ketogenesis is unknown but has been described in suckling rats and mice pups, possibly in order to allow large molecules, such as immunoglobulins, to pass over the intestinal barrier. Therefore, we hypothesized that ketone bodies could regulate intestinal barrier function, e.g., via regulation of tight junction proteins. The primary aim was to compare the effects of HFD that can induce intestinal ketogenesis to an equicaloric carbohydrate diet on inflammatory responses, nutrition sensing, and intestinal permeability in human jejunal mucosa. Fifteen healthy volunteers receiving a 2-week HFD diet compared to a high-carbohydrate diet were compared. Blood samples and mixed meal tests were performed at the end of each dietary period to examine inflammation markers and postprandial endotoxemia. Jejunal biopsies were assessed for protein expression using Western blotting, immunohistochemistry, and morphometric characteristics of tight junctions by electron microscopy. Functional analyses of permeability and ketogenesis were performed in Caco-2 cells, mice, and human enteroids. Ussing chambers were used to analyze permeability. CRP and ALP values were within normal ranges and postprandial endotoxemia levels were low and did not differ between the two diets. The PPARα receptor was ketone body-dependently reduced after HFD. None of the tight junction proteins studied, nor the basal electrical parameters, were different between the two diets. However, the ketone body inhibitor hymeglusin increased resistance in mucosal biopsies. In addition, the tight junction protein claudin-3 was increased by ketone inhibition in human enteroids. The ketone body β-Hydroxybutyrate (βHB) did not, however, change the mucosal transition of the large-size molecular FD4-probe or LPS in Caco-2 and mouse experiments. We found that PPARα expression was inhibited by the ketone body βHB. As PPARα regulates HMGCS expression, the ketone bodies thus exert negative feedback signaling on their own production. Furthermore, ketone bodies were involved in the regulation of permeability on intestinal mucosal cells in vitro and ex vivo. We were not, however, able to reproduce these effects on intestinal permeability in vivo in humans when comparing two weeks of high-fat with high-carbohydrate diet in healthy volunteers. Further, neither the expression of inflammation markers nor the aggregate tight junction proteins were changed. Thus, it seems that not only HFD but also other factors are needed to permit increased intestinal permeability in vivo. This indicates that the healthy gut can adapt to extremes of macro-nutrients and increased levels of intestinally produced ketone bodies, at least during a shorter dietary challenge.
Topics: Humans; Permeability; Male; Intestinal Mucosa; Diet, High-Fat; Ketone Bodies; Adult; Jejunum; Hydroxymethylglutaryl-CoA Synthase; Female; Animals; Mice; Claudin-3
PubMed: 38928261
DOI: 10.3390/ijms25126555 -
Journal of Medical Case Reports Jun 2024Insulin autoantibody syndrome (IAS), or Hirata disease, is caused by high concentrations of insulin autoantibodies, which result in spontaneous, mainly post-prandial,...
BACKGROUND
Insulin autoantibody syndrome (IAS), or Hirata disease, is caused by high concentrations of insulin autoantibodies, which result in spontaneous, mainly post-prandial, hypoglycemic episodes. We report a case of a previously healthy 67-year-old man presenting with recurrent fasting hypoglycemia culminating in a diagnosis of insulin autoimmune syndrome linked to omeprazole and probably spices, namely, coriander, and ginger.
CASE PRESENTATION
A previously healthy 67-year-old Sinhalese man presented with recurrent syncopal attacks for 3 months, which were found to be hypoglycemic episodes. He experienced mainly fasting hypoglycemic attacks, at a frequency gradually increasing to daily attacks. His cardiovascular, respiratory, abdominal, and neurologic examinations were normal. He was found to have insulin levels > 6000 mU/L and a post-polyethylene glycol insulin recovery of less than 9.5%. Contrast-enhanced computed tomography of the pancreas was normal. The diagnosis of insulin autoantibody syndrome was confirmed by testing for the insulin autoantibody level, yielding a level of > 300 U/mL. With regard to a possible trigger, he had a history of omeprazole intake for 2 weeks, 4 weeks prior to the onset of symptoms. He also consumed an herbal supplement containing coriander and ginger extracts daily for a period of 1 year, approximately 2 years prior to the onset of hypoglycemic attacks. He was commenced on prednisolone 30 mg daily, and hypoglycemic episodes responded dramatically, and thus he was tapered off corticosteroids.
CONCLUSION
Omeprazole-induced insulin autoantibody syndrome is likely in this patient; however, the known hypoglycemic effects of coriander and ginger make it worthwhile to consider a possible association with insulin autoantibody syndrome. In addition, this case report highlights the need to consider insulin autoantibody syndrome even in patients presenting with fasting hypoglycemic attacks.
Topics: Humans; Male; Aged; Hypoglycemia; Insulin Antibodies; Omeprazole; Autoimmune Diseases; Insulin; Zingiber officinale; Syndrome; Autoantibodies
PubMed: 38926797
DOI: 10.1186/s13256-024-04616-x -
Experimental Physiology Jun 2024The aim of this work is to determine the effect of upper-body high intensity interval training (HIIT) on cardiometabolic risks in individuals with chronic paraplegia....
The aim of this work is to determine the effect of upper-body high intensity interval training (HIIT) on cardiometabolic risks in individuals with chronic paraplegia. Twenty-seven individuals (14 females, 13 males, mean ± SD age: 46 ± 9 years) with chronic paraplegia (spinal cord injury between T2 and L5 >1-year post-injury) took part in a randomized controlled trial and were included in the final analysis. Participants in the HIIT group (n = 18) performed ∼30 min of arm crank exercise (60 s intervals at 80%-90% peak heart rate) four times per week, for 6 weeks. Participants in the control (CON) group (n = 9) were asked to maintain their habitual diet and physical activity patterns over the study period. Outcome measures were taken at baseline and follow-up. The primary outcome measures were fasting insulin, peak power output (PPO) and peak aerobic capacity ( ). Secondary outcome measures included body composition, postprandial glycaemic control, fasting blood lipids, inflammatory biomarkers and resting blood pressure. Differences between groups were assessed by ANCOVA, using baseline values as a covariate. PPO was higher in the HIIT (101 W, 97-106) compared to the CON (90 W, 83-96) group at follow-up (P = 0.006). There were no differences in fasting insulin (P = 0.415) or relative (P = 0.417). Postprandial Matsuda insulin sensitivity index (ISI) was higher in the HIIT (5.42, 4.69-6.15) compared to the CON (3.75, 2.46-5.04) group at follow-up (P = 0.036). Six weeks of upper-body HIIT increased PPO and ISI, with no other beneficial effect on cardiometabolic component risks in persons with chronic paraplegia. HIGHLIGHTS: What is the central question of this study? What is the effect of upper-body high intensity interval training (HIIT) on cardiometabolic component risks in individuals with chronic paraplegia? What is the main finding and its importance? Six weeks of upper-body HIIT increased PPO and improved insulin sensitivity, but had no beneficial effect on other cardiometabolic component risks in persons with chronic paraplegia. The large effect size observed for insulin sensitivity may be important in terms of reducing the risk of type-2 diabetes in this population.
PubMed: 38924175
DOI: 10.1113/EP091803 -
BioRxiv : the Preprint Server For... Jun 2024Humans with obesity and insulin resistance exhibit lipid accumulation in skeletal muscle, but the underlying biological mechanisms responsible for the accumulation of...
CONTEXT
Humans with obesity and insulin resistance exhibit lipid accumulation in skeletal muscle, but the underlying biological mechanisms responsible for the accumulation of lipid in the muscle of these individuals remain unknown.
OBJECTIVE
We investigated how plasma insulin modulates the extraction of circulating triglycerides (TGs) and non-esterified fatty acids (NEFAs) from dietary and endogenous sources in the muscle of lean, insulin-sensitive humans (Lean-IS) and contrasted these responses to those in humans with obesity and insulin resistance (Obese-IR).
METHODS
The studies were performed in a postprandial state associated with steady-state plasma TG concentrations. The arterio-venous blood sampling technique was employed to determine the extraction of circulating lipids across the forearm muscle before and after insulin infusion. We distinguished kinetics of TGs and NEFAs from dietary sources across muscle from those from endogenous sources by incorporating stable isotope-labeled triolein in ingested fat.
RESULTS
Plasma insulin rapidly suppressed the extraction of plasma TGs from endogenous, but not dietary, sources in the Lean-IS, but same response was absent in the Obese-IR. Furthermore, in the muscle of Lean-IS, plasma insulin decreased the extraction of circulating NEFAs from both dietary and endogenous sources, but in Obese-IR subjects this response was absent for NEFAs from dietary sources.
CONCLUSIONS
Partitioning of circulating lipids away from the skeletal muscle when plasma insulin increases, such as during the postprandial period, is impaired in humans with obesity and insulin resistance. Trial Registration: ClinicalTrials.gov ( NCT01860911 ).
PubMed: 38915696
DOI: 10.1101/2024.06.11.598550 -
PloS One 2024We overview of our whole room indirect calorimeter (WRIC), demonstrate validity and reliability of our WRIC, and explore a novel application of Bayesian hierarchical...
We overview of our whole room indirect calorimeter (WRIC), demonstrate validity and reliability of our WRIC, and explore a novel application of Bayesian hierarchical modeling to assess responses to small carbohydrate loads. To assess WRIC validity seven gas infusion studies were performed using a gas blender and profiles designed to mimic resting and postprandial metabolic events. Sixteen participants underwent fasting and postprandial measurements, during which they consumed a 75-kcal drink containing sucrose, dextrose, or fructose in a crossover design. Linear mixed effects models were used to compare resting and postprandial metabolic rate (MR) and carbohydrate oxidation. Postprandial carbohydrate oxidation trajectories for each participant and condition were modeled using Bayesian Hierarchical Modeling. Mean total error in infusions were 1.27 ± 0.67% and 0.42 ± 0.70% for VO2 and VCO2 respectively, indicating a high level of validity. Mean resting MR was similar across conditions ([Formula: see text] = 1.05 ± 0.03 kcal/min, p = 0.82, ICC: 0.91). While MR increased similarly among all conditions (~13%, p = 0.29), postprandial carbohydrate oxidation parameters were significantly lower for dextrose compared with sucrose or fructose. We provide evidence validating our WRIC and a novel application of statistical methods useful for research using WRIC.
Topics: Humans; Calorimetry, Indirect; Male; Female; Adult; Reproducibility of Results; Bayes Theorem; Postprandial Period; Cross-Over Studies; Young Adult; Energy Intake; Energy Metabolism; Oxidation-Reduction; Fasting
PubMed: 38900814
DOI: 10.1371/journal.pone.0304030 -
Science Translational Medicine Jun 2024The human ileum contains a high density of enteroendocrine L-cells, which release the appetite-suppressing hormones glucagon-like peptide-1 (GLP-1) and peptide tyrosine... (Randomized Controlled Trial)
Randomized Controlled Trial
The human ileum contains a high density of enteroendocrine L-cells, which release the appetite-suppressing hormones glucagon-like peptide-1 (GLP-1) and peptide tyrosine tyrosine (PYY) in response to food intake. Recent evidence highlighted the potential role of food structures in PYY release, but the link between food structures, ileal metabolites, and appetite hormone release remains unclear owing to limited access to intact human ileum. In a randomized crossover trial (ISRCTN11327221; isrctn.com), we investigated the role of human ileum in GLP-1 and PYY release by giving healthy volunteers diets differing in fiber and food structure: high-fiber (intact or disrupted food structures) or low-fiber disrupted food structures. We used nasoenteric tubes to sample chyme from the intact distal ileum lumina of humans in the fasted state and every 60 min for 480 min postprandially. We demonstrate the highly dynamic, wide-ranging molecular environment of the ileum over time, with a substantial decrease in ileum bacterial numbers and bacterial metabolites after food intake. We also show that high-fiber diets, independent of food structure, increased PYY release compared with a low-fiber diet during 0 to 240 min postprandially. High-fiber diets also increased ileal stachyose, and a disrupted high-fiber diet increased certain ileal amino acids. Treatment of human ileal organoids with ileal fluids or an amino acid and stachyose mixture stimulated expression in a similar profile to blood PYY concentrations, confirming the role of ileal metabolites in PYY release. Our study demonstrates the diet-induced changes over time in the metabolite environment of intact human ileum, which play a role in PYY release.
Topics: Humans; Ileum; Peptide YY; Diet; Adult; Male; Dietary Fiber; Glucagon-Like Peptide 1; Female; Metabolome; Postprandial Period; Cross-Over Studies; Young Adult
PubMed: 38896603
DOI: 10.1126/scitranslmed.adm8132 -
Drug Design, Development and Therapy 2024This study compared the pharmacokinetics, safety and bioequivalence (BE) of generic and original apremilast tablets in healthy Chinese subjects under fasting and... (Randomized Controlled Trial)
Randomized Controlled Trial Clinical Trial
OBJECTIVE
This study compared the pharmacokinetics, safety and bioequivalence (BE) of generic and original apremilast tablets in healthy Chinese subjects under fasting and postprandial conditions, providing sufficient evidence for abbreviated new drug application.
METHODS
A randomized, open-label, two-formulation, single-dose, two-period crossover pharmacokinetic study was performed. Thirty-two eligible healthy Chinese subjects were enrolled in fasting and postprandial studies, respectively. In each trial, subjects received a single 30-mg dose of the test or reference apremilast tablet, followed by a 7-day washout interval between periods. Serial blood samples were obtained for up to 48 h post-intake in each period, and the plasma concentrations of apremilast were determined by a validated method. The primary pharmacokinetic (PK) parameters, including the maximum plasma concentration (C), the areas under the plasma concentration-time curve (AUC, AUC), were calculated using the non-compartmental method. The geometric mean ratios of the two formulations and the corresponding 90% confidence intervals (CIs) were acquired for bioequivalence analysis. The safety of both formulations was also evaluated.
RESULTS
Under fasting and postprandial states, the PK parameters of the test drug were similar to those of the reference drug. The 90% CIs of the geometric mean ratios of the test to reference formulations were 94.09-103.44% for C, 94.05-103.51% for AUC, and 94.56-103.86% for AUC under fasting conditions, and 99.18-112.48% for C, 98.79-106.02% for AUC, and 98.95-105.89% for AUC under postprandial conditions, all of which were within the bioequivalence range of 80.00-125.00%. Both formulations were well tolerated, and no serious adverse events occurred during the study.
CONCLUSION
The trial confirmed that the PK parameters of the generic and original apremilast tablets were bioequivalent in healthy Chinese subjects under fasting and postprandial states, which met the predetermined regulatory standards. Both formulations were safe and well tolerated.
CLINICAL TRIAL REGISTRATION
chinaDrugtrials.org.cn, identifier CTR20191056 (July 30, 2019); chictr.org.cn, identifier ChiCTR2300076806 (October 19, 2023).
Topics: Humans; Therapeutic Equivalency; Thalidomide; Fasting; Postprandial Period; Adult; Male; Cross-Over Studies; Healthy Volunteers; Tablets; Young Adult; Female; Anti-Inflammatory Agents, Non-Steroidal; Asian People; Area Under Curve; Administration, Oral
PubMed: 38895175
DOI: 10.2147/DDDT.S461771 -
Nutrients Jun 2024Nutritional bars (NBs) are gaining popularity among healthy and athletic individuals, but postprandial antioxidative response has not been investigated. Therefore, the...
Nutritional bars (NBs) are gaining popularity among healthy and athletic individuals, but postprandial antioxidative response has not been investigated. Therefore, the current study examined the postprandial alterations in total phenolic content (TPC), total antioxidant capacity (T-AOC), malondialdehyde (MDA), and Superoxide dismutase (SOD) in the plasma of healthy individuals after the ingestion of 140 g (510 Kcal) from formulated date-based bars (DBBs) or fruit-based bars (FBBs). Firstly, the free and bound phenolic contents (PCs) were determined to be 10.15 and 12.98 and 6.19 and 3.57 mg GAE g, respectively. FBBs were significantly higher in free PC than DBBs, while DBBs were considerably higher in bound PC than FBBs. Secondly, twenty participants with age, height, weight, body mass index (BMI), fat mass, and fat-free mass averages of 21.4 years, 170.0 cm, 66.3 kg, 22.9 kg m, 14.5, and 29.2 kg, respectively, were subjected to metabolic experiments (ISRCTN19386758). Ingestion of 140 g of FBB or DBB resulted in 288.50 or 302.14 µg TPC mL blood, respectively. Postprandial TPC content increased with time progression and peaked after 120 min. T-AOC contents averaged 22.63 and 23.61 U mL before ingestion of FBBs or DBBs, respectively. The T-AOC content increased significantly 120 and 180 min after ingestion of DBBs, while no significant change was noted after consuming FBBs. A significant decrease in MDA content was observed 180 min after consuming DBBs, while no significant change was noted after consuming FBBs. SOD concentrations ranged from 193.99 to 201.07 U L in FBBs and DBBs, respectively. No considerable response was noted up to 3 h after ingestion of FBBs. On the contrary, a significant response was found 120 min after consuming DBBs. Pearson's correlation coefficient indicated a highly significant positive correlation coefficient ( < 0.01) between T-AOC and either MDA or SOD, as well as between MDA and SOD. The principal component analysis demonstrated a strong and positive relationship between SOD and TPC at 60 and 120 min after DBB ingestion. In conclusion, the relative changes in postprandial responses in T-AOC and MDA did not significantly ( > 0.05) differ between DBBs and FBBs, except for TPC ( = 0.04, paired -test) and SOD ( = 0.003, paired -test). Further studies with an extended experimental time are needed to confirm the current findings.
Topics: Humans; Postprandial Period; Antioxidants; Fruit; Male; Young Adult; Malondialdehyde; Female; Superoxide Dismutase; Adult; Phenols; Food, Formulated; Healthy Volunteers
PubMed: 38892726
DOI: 10.3390/nu16111794 -
Nutrients May 2024The consumption of protein-rich foods stimulates satiety more than other macronutrient-rich foods; however, the underlying mechanisms-of-action are not...
Examining the Direct and Indirect Effects of Postprandial Amino Acid Responses on Markers of Satiety following the Acute Consumption of Lean Beef-Rich Meals in Healthy Women with Overweight.
The consumption of protein-rich foods stimulates satiety more than other macronutrient-rich foods; however, the underlying mechanisms-of-action are not well-characterized. The objective of this study was to identify the direct and indirect effects of postprandial amino acid (AA) responses on satiety. Seventeen women (mean ± SEM, age: 33 ± 1 year; BMI: 27.8 ± 0.1 kg/m) consumed a eucaloric, plant-based diet containing two servings of lean beef/day (i.e., 7.5 oz (207 g)) for 7 days. During day 6, the participants completed a 12 h controlled-feeding, clinical testing day including repeated satiety questionnaires and blood sampling to assess pre- and postprandial plasma AAs, PYY, and GLP-1. Regression and mediation analyses were completed to assess AA predictors and hormonal mediators. Total plasma AAs explained 41.1% of the variance in perceived daily fullness ( < 0.001), 61.0% in PYY ( < 0.001), and 66.1% in GLP-1 ( < 0.001) concentrations, respectively. Several individual AAs significantly predicted fluctuations in daily fullness, PYY, and GLP-1. In completing mediation analyses, the effect of plasma leucine on daily fullness was fully mediated by circulating PYY concentrations (indirect effect = B: 0.09 [Boot 95% CI: 0.032, 0.17]) as no leucine-fullness direct effect was observed. No other mediators were identified. Although a number of circulating AAs predict satiety, leucine was found to do so through changes in PYY concentrations in middle-aged women.
Topics: Humans; Female; Adult; Postprandial Period; Amino Acids; Red Meat; Peptide YY; Satiation; Overweight; Glucagon-Like Peptide 1; Biomarkers; Meals; Animals; Cattle; Satiety Response
PubMed: 38892651
DOI: 10.3390/nu16111718 -
Nutrients May 2024Non-communicable diseases (NCDs) are becoming an increasingly important health concern due to a rapidly ageing global population. The fastest growing NCD, type 2... (Randomized Controlled Trial)
Randomized Controlled Trial
Understanding the Impact of Different Doses of Reducose Mulberry Leaf Extract on Blood Glucose and Insulin Responses after Eating a Complex Meal: Results from a Double-Blind, Randomised, Crossover Trial.
Non-communicable diseases (NCDs) are becoming an increasingly important health concern due to a rapidly ageing global population. The fastest growing NCD, type 2 diabetes mellitus (T2DM), is responsible for over 2 million deaths annually. Lifestyle changes, including dietary changes to low glycemic response (GR) foods, have been shown to reduce the risk of developing T2DM. The aim of this study was to investigate whether three different doses of Reducose, a mulberry leaf extract, could lower the GR and insulinemic responses (IR) to a full meal challenge in healthy individuals. A double-blind, randomised, placebo-controlled, repeat-measure, crossover design trial was conducted by the Oxford Brookes Centre for Nutrition and Health; 37 healthy individuals completed the study. Participants consumed capsules containing either 200 mg, 225 mg, 250 mg Reducose or placebo before a test meal consisting of 150 g white bread and egg mayo filler. Capillary blood samples were collected at 15-min intervals in the first hour and at 30-min intervals over the second and third hours to determine glucose and plasma insulin levels. The consumption of all three doses of Reducose resulted in significantly lower blood glucose and plasma insulin levels compared to placebo. All three doses of Reducose (200 mg, 225 mg, 250 mg) significantly lowered glucose iAUC 120 by 30% ( = 0.003), 33% ( = 0.001) and 32% ( = 0.002), respectively, compared with placebo. All three doses of Reducose (200 mg, 225 mg, 250 mg) significantly lowered the plasma insulin iAUC 120 by 31% ( = 0.024), 34% ( = 0.004) and 38% ( < 0.001), respectively. The study demonstrates that the recommended dose (250 mg) and two lower doses (200 mg, 225 mg) of Reducose can be used to help lower the GR and IR of a full meal containing carbohydrates, fats and proteins.
Topics: Humans; Cross-Over Studies; Plant Extracts; Double-Blind Method; Morus; Blood Glucose; Male; Insulin; Female; Adult; Plant Leaves; Postprandial Period; Middle Aged; Meals; Young Adult; Glycemic Index; Diabetes Mellitus, Type 2
PubMed: 38892603
DOI: 10.3390/nu16111670