Metabolic Effects of Glucose-Fructose Co-Ingestion Compared to Glucose Alone during Exercise in Type 1 Diabetes.

This paper aims to compare the metabolic effects of glucose-fructose co-ingestion (GLUFRU) with glucose alone (GLU) in exercising individuals with type 1 diabetes mellitus. Fifteen male individuals with type 1 diabetes (HbA1c 7.0% ± 0.

Test-retest analysis of multiple P magnetization exchange pathways using asymmetric adiabatic inversion.

Purpose: A P-MR inversion transfer (IT) method with a short adiabatic inversion pulse is proposed and its test-retest reliability was evaluated for two spectral fitting strategies.

Methods: Assessment in a test-retest design (3 Tesla, vastus muscles, 12 healthy volunteers, 14 inversion times, 22 ms asymmetric adiabatic inversion pulse, adiabatic excitation); spectral fitting in Fitting Tool for Interrelated Arrays of Datasets (FitAID) and Java Magnetic Resonance User Interface (jMRUI); least squares solution of the Bloch-McConnell-Solomon matrix formalism including all 14 measured time-points with equal weighting.

Results: The cohort averages of k[PCr→γ-ATP] (phosphocreatine, PCr; adenosine triphosphate, ATP) are 0.

Methodological and physiological test-retest reliability of (13) C-MRS glycogen measurements in liver and in skeletal muscle of patients with type 1 diabetes and matched healthy controls.

Glycogen is a major substrate in energy metabolism and particularly important to prevent hypoglycemia in pathologies of glucose homeostasis such as type 1 diabetes mellitus (T1DM). (13) C-MRS is increasingly used to determine glycogen in skeletal muscle and liver non-invasively; however, the low signal-to-noise ratio leads to long acquisition times, particularly when glycogen levels are determined before and after interventions. In order to ease the requirements for the subjects and to avoid systematic effects of the lengthy examination, we evaluated if a standardized preparation period would allow us to shift the baseline (pre-intervention) experiments to a preceding day.

Effects of aerobic exercise on ectopic lipids in patients with growth hormone deficiency before and after growth hormone replacement therapy.

Growth hormone replacement therapy (GHRT) increases exercise capacity and insulin resistance while it decreases fat mass in growth hormone-deficient patients (GHD). Ectopic lipids (intramyocellular (IMCL) and intrahepatocellular lipids (IHCL) are related to insulin resistance. The effect of GHRT on ectopic lipids is unknown.

Metabolic and hormonal response to intermittent high-intensity and continuous moderate intensity exercise in individuals with type 1 diabetes: a randomised crossover study.

Aims/hypothesis: To investigate exercise-related fuel metabolism in intermittent high-intensity (IHE) and continuous moderate intensity (CONT) exercise in individuals with type 1 diabetes mellitus.

Methods: In a prospective randomised open-label cross-over trial twelve male individuals with well-controlled type 1 diabetes underwent a 90 min iso-energetic cycling session at 50% maximal oxygen consumption ([Formula: see text]), with (IHE) or without (CONT) interspersed 10 s sprints every 10 min without insulin adaptation. Euglycaemia was maintained using oral (13)C-labelled glucose.

Noninvasive estimation of oxygen consumption in human calf muscle through combined NMR measurements of ASL perfusion and T₂ oxymetry.

The objective of this work was to demonstrate the feasibility of measuring muscle O2 consumption (V˙O2) noninvasively with a combination of functional nuclear magnetic resonance (NMR) imaging methods, and to verify that changes in muscle V˙O2 can be detected with a temporal resolution compatible with physiological investigation and patient ease. T2-based oxymetry of arterial and venous blood was combined with the arterial-spin labeling (ASL)-based determination of muscle perfusion. These measurements were performed on 8 healthy volunteers under normoxic and hypoxic conditions in order to assess the sensitivity of measurements over a range of saturation values.

Comparison of (31)P saturation and inversion magnetization transfer in human liver and skeletal muscle using a clinical MR system and surface coils.

(31)P MRS magnetization transfer ((31)P-MT) experiments allow the estimation of exchange rates of biochemical reactions, such as the creatine kinase equilibrium and adenosine triphosphate (ATP) synthesis. Although various (31)P-MT methods have been successfully used on isolated organs or animals, their application on humans in clinical scanners poses specific challenges. This study compared two major (31)P-MT methods on a clinical MR system using heteronuclear surface coils.

The effect of aerobic exercise on intrahepatocellular and intramyocellular lipids in healthy subjects.

Background: Intrahepatocellular (IHCL) and intramyocellular (IMCL) lipids are ectopic lipid stores. Aerobic exercise results in IMCL utilization in subjects over a broad range of exercise capacity. IMCL and IHCL have been related to impaired insulin action at the skeletal muscle and hepatic level, respectively.

Effects of supplementation with essential amino acids on intrahepatic lipid concentrations during fructose overfeeding in humans.

Background: A high dietary protein intake has been shown to blunt the deposition of intrahepatic lipids in high-fat- and high-carbohydrate-fed rodents and humans.

Objective: The aim of this study was to evaluate the effect of essential amino acid supplementation on the increase in hepatic fat content induced by a high-fructose diet in healthy subjects.

Design: Nine healthy male volunteers were studied on 3 occasions in a randomized, crossover design after 6 d of dietary intervention.

Magnetic resonance imaging based determination of body compartments with the versatile, interactive sparse sampling (VISS) method.

Purpose: To investigate the inhomogeneity of radiofrequency fields at higher field strengths that can interfere with established volumetric methods, in particular for the determination of visceral (VAT) and subcutaneous adipose tissue (SCAT). A versatile, interactive sparse sampling (VISS) method is proposed to determine VAT, SCAT, and also total body volume (TBV).

Materials And Methods: VISS is based on a separation of major components by contour lines, followed by a sparse sampling algorithm, and eventually a quick manual correction.

Effect of two β-alanine dosing protocols on muscle carnosine synthesis and washout.

Carnosine (β-alanyl-L-histidine) is found in high concentrations in skeletal muscle and chronic β-alanine (BA) supplementation can increase carnosine content. This placebo-controlled, double-blind study compared two different 8-week BA dosing regimens on the time course of muscle carnosine loading and 8-week washout, leading to a BA dose-response study with serial muscle carnosine assessments throughout. Thirty-one young males were randomized into three BA dosing groups: (1) high-low: 3.

Fructose and galactose enhance postexercise human liver glycogen synthesis.

Purpose: Both liver and muscle glycogen stores play a fundamental role in exercise and fatigue, but the effect of different CHO sources on liver glycogen synthesis in humans is unclear. The aim was to compare the effect of maltodextrin (MD) drinks containing galactose, fructose, or glucose on postexercise liver glycogen synthesis.

Methods: In this double-blind, triple crossover, randomized clinical trial, 10 well-trained male cyclists performed three experimental exercise sessions separated by at least 1 wk.

Effects of a whey protein supplementation on intrahepatocellular lipids in obese female patients.

Background & Aims: High protein diets have been shown to improve hepatic steatosis in rodent models and in high-fat fed humans. We therefore evaluated the effects of a protein supplementation on intrahepatocellular lipids (IHCL), and fasting plasma triglycerides in obese non diabetic women.

Methods: Eleven obese women received a 60 g/day whey protein supplement (WPS) for 4-weeks, while otherwise nourished on a spontaneous diet, IHCL concentrations, visceral body fat, total liver volume (MR), fasting total-triglyceride and cholesterol concentrations, glucose tolerance (standard 75 g OGTT), insulin sensitivity (HOMA IS index), creatinine clearance, blood pressure and body composition (bio-impedance analysis) were assessed before and after 4-week WPS.