Objective: The aim of this study was to investigate the impact of the sodium-glucose cotransporter 2 (SGLT2) inhibitor dapagliflozin on tissue fatty acid (FA) uptake in the skeletal muscle, brain, small intestine, and subcutaneous and visceral adipose tissue of individuals with type 2 diabetes by using positron emission tomography (PET).
Research Design And Methods: In a 6-week randomized double-blind placebo-controlled trial, 53 patients with type 2 diabetes treated with metformin received either 10 mg dapagliflozin or placebo daily. Tissue FA uptake was quantified at baseline and end of treatment with PET and the long-chain FA analog radiotracer 14(R,S)-[18F]fluoro-6-thia-heptadecanoic acid.
Context: Studies on human renal metabolism are scanty. Nowadays, functional imaging allows the characterization of renal metabolism in a noninvasive manner. We have recently demonstrated that fluorodeoxyglucose F18 (18F FDG) positron emission tomography can be used to analyze renal glucose uptake (GU) rates, and that the renal cortex is an insulin-sensitive tissue.
View Article and Find Full Text PDFAims: We sought to evaluate the mechanism of angiotensin receptor-neprilysin inhibitor (ARNI) sacubitril/valsartan therapy and compare it with a valsartan-only control group in patients with heart failure with reduced ejection fraction (HFrEF).
Methods And Results: The study was a phase IV, prospective, randomized, double-blind, parallel-group study in patients with New York Heart Association class II-III heart failure and left ventricular ejection fraction (LVEF) ≤35%. During a 6-week run-in period, all patients received valsartan therapy, which was up-titrated to the highest tolerated dose level (80 mg bid or 160 mg bid) and then randomized to either valsartan or sacubitril/valsartan.
The human brain undergoes metabolic adaptations in obesity, but the underlying mechanisms have remained largely unknown. We compared concentrations of often reported brain metabolites measured with magnetic resonance spectroscopy (H-MRS, 3 T MRI) in the occipital lobe in subjects with obesity and lean controls under different metabolic conditions (fasting, insulin clamp, following weight loss). Brain glucose uptake (BGU) quantified with F-fluorodeoxyglucose positron emission tomography (F-FDG-PET)) was also performed in a subset of subjects during clamp.
View Article and Find Full Text PDFIntroduction: During the transcatheter aortic valve replacement (TAVR) procedure, hemodynamic measurements can be used to evaluate transcatheter heart valve (THV) performance. We hypothesized that the occurrence of a significant decrease in invasive aortic pressure immediately after annular contact by a self-expanding THV indicates effective annular sealing. This phenomenon could thus be used as a marker for the occurrence of paravalvular leak (PVL).
View Article and Find Full Text PDFEur J Nucl Med Mol Imaging
May 2023
Purpose: Secretin activates brown adipose tissue (BAT) and induces satiation in both mice and humans. However, the exact brain mechanism of this satiety inducing, secretin-mediated gut-BAT-brain axis is largely unknown.
Methods And Results: In this placebo-controlled, single-blinded neuroimaging study, firstly using [F]-fluorodeoxyglucose (FDG) PET measures (n = 15), we established that secretin modulated brain glucose consumption through the BAT-brain axis.
Purpose: Photoperiod determines the metabolic activity of brown adipose tissue (BAT) and affects the food intake and body mass of mammals. Sympathetic innervation of the BAT controls thermogenesis and facilitates physiological adaption to seasonal changes, but the exact mechanism remains elusive. Previous studies have shown that central opioid signaling regulates BAT thermogenesis, and that the expression of the brain mu-opioid receptor (MOR) varies seasonally.
View Article and Find Full Text PDFNeurofilament light chain (NfL) is a novel biomarker reflecting neuroaxonal damage and associates with brain atrophy, and glial fibrillary acidic protein (GFAP) is a marker of astrocytic activation, associated with several neurodegenerative diseases. Since obesity is associated with increased risk for several neurodegenerative disorders, we hypothesized that circulating NfL and GFAP levels could reflect neuronal damage in obese patients. 28 morbidly obese and 18 lean subjects were studied with voxel based morphometry (VBM) MRI to assess gray and white matter densities.
View Article and Find Full Text PDFAm J Physiol Endocrinol Metab
January 2022
The cardiac benefits of gastrointestinal hormones have been of interest in recent years. The aim of this study was to explore the myocardial and renal effects of the gastrointestinal hormone secretin in the GUTBAT trial (NCT03290846). A placebo-controlled crossover study was conducted on 15 healthy males in fasting conditions, where subjects were blinded to the intervention.
View Article and Find Full Text PDFFront Endocrinol (Lausanne)
February 2022
Secretin is the first hormone that has been discovered, inaugurating the era and the field of endocrinology. Despite the initial focus, the interest in its actions faded away over the decades. However, there is mounting evidence regarding the pleiotropic beneficial effects of secretin on whole-body homeostasis.
View Article and Find Full Text PDFPurpose: While brown adipose tissue (BAT) activity is known to be associated with both muscle and adipose tissue volumes, the association between BAT and muscle composition remains unclear, especially in adults. Therefore, the present study aimed to examine the association between BAT parameters (glucose uptake and fat-fraction) and muscle volumes and intramuscular adipose tissue contents among healthy young and middle-aged men.
Methods: BAT glucose uptake was determined using positron emission tomography with [F]-2-deoxy-2-fluoro-D-glucose (F-FDG) during cold exposure in 19 young and middle-aged men (36.
Brown adipose tissue (BAT) thermogenesis is activated by feeding. Recently, we revealed a secretin-mediated gut-BAT-brain axis, which stimulates satiation in mice, but the purpose of meal-induced BAT activation in humans has been unclear. In this placebo-controlled, randomized crossover study, we investigated the effects of intravenous secretin on BAT metabolism (measured with [F]FDG and [O]HO positron emission tomography) and appetite (measured with functional magnetic resonance imaging) in healthy, normal weight men (GUTBAT trial no.
View Article and Find Full Text PDFAim: To explore the early effects of dapagliflozin on myocardial function and metabolism in patients with type 2 diabetes without heart failure.
Materials And Methods: Patients with type 2 diabetes on metformin treatment were randomized to double-blind, 6-week placebo or dapagliflozin 10 mg daily treatment. Investigations included cardiac function and structure with myocardial resonance imaging; cardiac oxygen consumption, perfusion and efficiency with [ C]-acetate positron emission tomography (PET); and cardiac and hepatic fatty acid uptake with [ F]-6-thia-heptadecanoic acid PET, analysed by ANCOVA as least square means with 95% confidence intervals.
The aim of this study was to examine the associations of cardiometabolic health markers with device-measured sedentary behavior (SB) duration and different intensities of physical activity (PA) among overweight working-aged adults with low self-reported PA levels. This cross-sectional analysis included 144 subjects (42 men) with mean age of 57 (SD 6.5) years and mean BMI of 31.
View Article and Find Full Text PDFThe molecular mediator and functional significance of meal-associated brown fat (BAT) thermogenesis remains elusive. Here, we identified the gut hormone secretin as a non-sympathetic BAT activator mediating prandial thermogenesis, which consequentially induces satiation, thereby establishing a gut-secretin-BAT-brain axis in mammals with a physiological role of prandial thermogenesis in the control of satiation. Mechanistically, meal-associated rise in circulating secretin activates BAT thermogenesis by stimulating lipolysis upon binding to secretin receptors in brown adipocytes, which is sensed in the brain and promotes satiation.
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