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Chris Boesch - One of the best experts on this subject based on the ideXlab platform.

  • The Effect of Aerobic Exercise on Intrahepatocellular and Intramyocellular Lipids in Healthy Subjects
    2016
    Co-Authors: Andrea Egger, Chris Boesch, Peter Diem, Sabin Allemann, Christoph Stettler, Tania Buehler, Emanuel R. Christ
    Abstract:

    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. The acute effect of aerobic exercise on IHCL is unknown. Possible regulatory factors include exercise capacity, insulin sensitivity and fat availability subcutaneous and visceral fat mass). Aim: To concomitantly investigate the effect of aerobic exercise on IHCL and IMCL in healthy subjects, using Magnetic Resonance spectroscopy. Methods: Normal weight, healthy subjects were included. Visit 1 consisted of a determination of VO2max on a treadmill. Visit 2 comprised the assessment of hepatic and peripheral insulin sensitivity by a two-step hyperinsulinaemic euglycaemic clamp. At Visit 3, subcutaneous and visceral fat mass were assessed by whole body MRI, IHCL and IMCL before and after a 2-hours aerobic exercise (50 % of VO2max) using 1H-MR-spectroscopy. Results: Eighteen volunteers (12M, 6F) were enrolled in the study (age, 37.663.2 years, mean6SEM; VO2max, 53.462.9 mL/ kg/min). Two hours aerobic exercise resulted in a significant decrease in IMCL (222.663.3, % from baseline) and increase i

  • the effect of aerobic exercise on intrahepatocellular and Intramyocellular Lipids in healthy subjects
    PLOS ONE, 2013
    Co-Authors: Andrea Egger, Chris Boesch, Roland Kreis, Peter Diem, Sabin Allemann, Christoph Stettler, Tania Buehler, Emanuel Christ
    Abstract:

    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. The acute effect of aerobic exercise on IHCL is unknown. Possible regulatory factors include exercise capacity, insulin sensitivity and fat availability subcutaneous and visceral fat mass). AIM To concomitantly investigate the effect of aerobic exercise on IHCL and IMCL in healthy subjects, using Magnetic Resonance spectroscopy. METHODS Normal weight, healthy subjects were included. Visit 1 consisted of a determination of VO2max on a treadmill. Visit 2 comprised the assessment of hepatic and peripheral insulin sensitivity by a two-step hyperinsulinaemic euglycaemic clamp. At Visit 3, subcutaneous and visceral fat mass were assessed by whole body MRI, IHCL and IMCL before and after a 2-hours aerobic exercise (50% of VO(2max)) using ¹H-MR-spectroscopy. RESULTS Eighteen volunteers (12M, 6F) were enrolled in the study (age, 37.6±3.2 years, mean±SEM; VO(2max), 53.4±2.9 mL/kg/min). Two hours aerobic exercise resulted in a significant decrease in IMCL (-22.6±3.3, % from baseline) and increase in IHCL (+34.9±7.6, % from baseline). There was no significant correlation between the exercise-induced changes in IMCL and IHCL and exercise capacity, subcutaneous and visceral fat mass and hepatic or peripheral insulin sensitivity. CONCLUSIONS IMCL and IHCL are flexible ectopic lipid stores that are acutely influenced by physical exercise, albeit in different directions. TRIAL REGISTRATION ClinicalTrial.gov NCT00491582.

  • restricted or severely hindered diffusion of Intramyocellular Lipids in human skeletal muscle shown by in vivo proton mr spectroscopy
    Magnetic Resonance in Medicine, 2012
    Co-Authors: Vaclav Brandejsky, Roland Kreis, Chris Boesch
    Abstract:

    Although magnetic resonance spectroscopy can be used as a unique tool to study molecular diffusion, it is rarely used to measure the diffusion properties of Intramyocellular and extramyocellular Lipids. Lipids have very low apparent diffusion coefficients (ADCs), which make these measurements difficult and necessitate strong diffusion gradients and long diffusion times. Consequence is that these measurements have inherently low signal-to-noise ratio and are prone to artifacts. The addition of physiological triggering and individual storage and processing of the spectra is seen to be a possible approach to maximize signal intensity and achieve high reproducibility of the experiments. Thus, the optimized measurement protocol was used to investigate the diffusion properties of Lipids in human skeletal muscle in vivo. At a diffusion time of about 110 ms, Intramyocellular Lipids show a significantly lower ADC (2.0 × 10(-6) mm(2)/s, 95% confidence interval 1.10 × 10(-6) to 2.94 × 10(-6) mm(2)/s) than extramyocellular Lipids (1.58 × 10(-5) mm(2)/s, 95% confidence interval 1.41 × 10(-5) to 1.75 × 10(-5) mm(2)/s). Because the chemical properties of both lipid pools can be assumed to be similar, the difference can only be attributed to restricted or severely hindered diffusion in the Intramyocellular droplets.

  • Skeletal muscle 1H MRSI before and after prolonged exercise. I. muscle specific depletion of Intramyocellular Lipids
    Magnetic resonance in medicine, 2012
    Co-Authors: Peter Vermathen, Monica Zehnder, Pierre Saillen, Andreas Boss, Chris Boesch
    Abstract:

    Aim of the study was to determine distribution and depletion patterns of Intramyocellular Lipids (IMCL) in leg muscles before and after two types of standardized endurance exercise. ¹H-magnetic resonance spectroscopic imaging was performed (1) in the thigh of eight-trained cyclists after exercising on an ergometer for 3 h at 52 ± 8% of maximal speed and (2) in the lower leg of eight-trained runners after exercising on a treadmill for 3 h at 49 ± 3% of maximal workload. Pre-exercise IMCL contents were reduced postexercise in 11 out of 13 investigated upper and lower leg muscles (P < 0.015 for all). A strong linear correlation with a slope of ∼0.5 between pre-exercise IMCL content and IMCL depletion was found. IMCL depletion differed strongly between muscles. Absolute and also relative IMCL reduction was significantly higher in muscles with predominantly slow fibers compared to those with fast fibers. Creatine levels and fiber orientation were stable and unchanged after exercise, while trimethyl-ammonium groups increased. This is presented in the accompanying paper. In conclusion, a systematic comparison of metabolic changes in cross sections of the upper and lower leg was performed. The results imply that pre-exercise IMCL levels determine the degree of IMCL depletion after exercise.

  • effects of a short term overfeeding with fructose or glucose in healthy young males
    British Journal of Nutrition, 2010
    Co-Authors: Emilienne Tudor Ngo Sock, Chris Boesch, Roland Kreis, Michael Ith, Luc Tappy
    Abstract:

    Consumption of simple carbohydrates has markedly increased over the past decades, and may be involved in the increased prevalence in metabolic diseases. Whether an increased intake of fructose is specifically related to a dysregulation of glucose and lipid metabolism remains controversial. We therefore compared the effects of hypercaloric diets enriched with fructose (HFrD) or glucose (HGlcD) in healthy men. Eleven subjects were studied in a randomised order after 7 d of the following diets: (1) weight maintenance, control diet; (2) HFrD (3.5 g fructose/kg fat-free mass (ffm) per d, +35 % energy intake); (3) HGlcD (3.5 g glucose/kg ffm per d, +35 % energy intake). Fasting hepatic glucose output (HGO) was measured with 6,6-2H2-glucose. Intrahepatocellular Lipids (IHCL) and Intramyocellular Lipids (IMCL) were measured by 1H magnetic resonance spectroscopy. Both fructose and glucose increased fasting VLDL-TAG (HFrD: +59 %, P < 0.05; HGlcD: +31 %, P = 0.11) and IHCL (HFrD: +52 %, P < 0.05; HGlcD: +58 %, P = 0.06). HGO increased after both diets (HFrD: +5 %, P < 0.05; HGlcD: +5 %, P = 0.05). No change was observed in fasting glycaemia, insulin and alanine aminotransferase concentrations. IMCL increased significantly only after the HGlcD (HFrD: +24 %, NS; HGlcD: +59 %, P < 0.05). IHCL and VLDL-TAG were not different between hypercaloric HFrD and HGlcD, but were increased compared to values observed with a weight maintenance diet. However, glucose led to a higher increase in IMCL than fructose.

Roland Kreis - One of the best experts on this subject based on the ideXlab platform.

  • impaired repletion of Intramyocellular Lipids in patients with growth hormone deficiency after a bout of aerobic exercise
    Growth Hormone & Igf Research, 2018
    Co-Authors: Hannah Loher, Roland Kreis, Emanuel Christ, Stefan Jenni, Julie Bucher, Marion Krusi, Christoph Hans Boesch
    Abstract:

    Abstract Background Ectopic Lipids such as Intramyocellular Lipids (IMCL) are depleted by exercise and repleted by diet, whereas intrahepatocellular Lipids (IHCL) are increased immediately after exercise. So far, it is unclear how ectopic Lipids behave 24 h after exercise and whether the lack of growth hormone (GH) significantly affects ectopic Lipids 24 h after exercise. Methods Seven male patients with growth hormone deficiency (GHD) and seven sedentary male control subjects (CS) were included. VO2max was assessed by spiroergometry; visceral and subcutaneous fat by whole body MRI. 1H-MR-spectroscopy was performed in M. vastus intermedius and in the liver before and after 2 h of exercise at 50% VO2max and 24 h thereafter, while diet and physical activity were standardized. Results Sedentary male subjects (7 GHD, 7 CS) were recruited. Age, BMI, waist circumference, visceral and subcutaneous fat mass was not significantly different between GHD and CS. VO2max was significantly lower in GHD vs. CS. IMCL were diminished through aerobic exercise in both groups: (−11.5 ± 21.9% in CS; −8.9% ±19.1% in GHD) and restored after 24 h in CS (−5.5 ± 26.6% compared to baseline) but not in GHD (−17.9 ± 15.3%). IHCL increased immediately after exercise and decreased to baseline within 24 h. Conclusion These findings suggest that GHD may affect repletion of IMCL 24 h after aerobic exercise.

  • the effect of aerobic exercise on intrahepatocellular and Intramyocellular Lipids in healthy subjects
    PLOS ONE, 2013
    Co-Authors: Andrea Egger, Chris Boesch, Roland Kreis, Peter Diem, Sabin Allemann, Christoph Stettler, Tania Buehler, Emanuel Christ
    Abstract:

    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. The acute effect of aerobic exercise on IHCL is unknown. Possible regulatory factors include exercise capacity, insulin sensitivity and fat availability subcutaneous and visceral fat mass). AIM To concomitantly investigate the effect of aerobic exercise on IHCL and IMCL in healthy subjects, using Magnetic Resonance spectroscopy. METHODS Normal weight, healthy subjects were included. Visit 1 consisted of a determination of VO2max on a treadmill. Visit 2 comprised the assessment of hepatic and peripheral insulin sensitivity by a two-step hyperinsulinaemic euglycaemic clamp. At Visit 3, subcutaneous and visceral fat mass were assessed by whole body MRI, IHCL and IMCL before and after a 2-hours aerobic exercise (50% of VO(2max)) using ¹H-MR-spectroscopy. RESULTS Eighteen volunteers (12M, 6F) were enrolled in the study (age, 37.6±3.2 years, mean±SEM; VO(2max), 53.4±2.9 mL/kg/min). Two hours aerobic exercise resulted in a significant decrease in IMCL (-22.6±3.3, % from baseline) and increase in IHCL (+34.9±7.6, % from baseline). There was no significant correlation between the exercise-induced changes in IMCL and IHCL and exercise capacity, subcutaneous and visceral fat mass and hepatic or peripheral insulin sensitivity. CONCLUSIONS IMCL and IHCL are flexible ectopic lipid stores that are acutely influenced by physical exercise, albeit in different directions. TRIAL REGISTRATION ClinicalTrial.gov NCT00491582.

  • restricted or severely hindered diffusion of Intramyocellular Lipids in human skeletal muscle shown by in vivo proton mr spectroscopy
    Magnetic Resonance in Medicine, 2012
    Co-Authors: Vaclav Brandejsky, Roland Kreis, Chris Boesch
    Abstract:

    Although magnetic resonance spectroscopy can be used as a unique tool to study molecular diffusion, it is rarely used to measure the diffusion properties of Intramyocellular and extramyocellular Lipids. Lipids have very low apparent diffusion coefficients (ADCs), which make these measurements difficult and necessitate strong diffusion gradients and long diffusion times. Consequence is that these measurements have inherently low signal-to-noise ratio and are prone to artifacts. The addition of physiological triggering and individual storage and processing of the spectra is seen to be a possible approach to maximize signal intensity and achieve high reproducibility of the experiments. Thus, the optimized measurement protocol was used to investigate the diffusion properties of Lipids in human skeletal muscle in vivo. At a diffusion time of about 110 ms, Intramyocellular Lipids show a significantly lower ADC (2.0 × 10(-6) mm(2)/s, 95% confidence interval 1.10 × 10(-6) to 2.94 × 10(-6) mm(2)/s) than extramyocellular Lipids (1.58 × 10(-5) mm(2)/s, 95% confidence interval 1.41 × 10(-5) to 1.75 × 10(-5) mm(2)/s). Because the chemical properties of both lipid pools can be assumed to be similar, the difference can only be attributed to restricted or severely hindered diffusion in the Intramyocellular droplets.

  • effects of a short term overfeeding with fructose or glucose in healthy young males
    British Journal of Nutrition, 2010
    Co-Authors: Emilienne Tudor Ngo Sock, Chris Boesch, Roland Kreis, Michael Ith, Luc Tappy
    Abstract:

    Consumption of simple carbohydrates has markedly increased over the past decades, and may be involved in the increased prevalence in metabolic diseases. Whether an increased intake of fructose is specifically related to a dysregulation of glucose and lipid metabolism remains controversial. We therefore compared the effects of hypercaloric diets enriched with fructose (HFrD) or glucose (HGlcD) in healthy men. Eleven subjects were studied in a randomised order after 7 d of the following diets: (1) weight maintenance, control diet; (2) HFrD (3.5 g fructose/kg fat-free mass (ffm) per d, +35 % energy intake); (3) HGlcD (3.5 g glucose/kg ffm per d, +35 % energy intake). Fasting hepatic glucose output (HGO) was measured with 6,6-2H2-glucose. Intrahepatocellular Lipids (IHCL) and Intramyocellular Lipids (IMCL) were measured by 1H magnetic resonance spectroscopy. Both fructose and glucose increased fasting VLDL-TAG (HFrD: +59 %, P < 0.05; HGlcD: +31 %, P = 0.11) and IHCL (HFrD: +52 %, P < 0.05; HGlcD: +58 %, P = 0.06). HGO increased after both diets (HFrD: +5 %, P < 0.05; HGlcD: +5 %, P = 0.05). No change was observed in fasting glycaemia, insulin and alanine aminotransferase concentrations. IMCL increased significantly only after the HGlcD (HFrD: +24 %, NS; HGlcD: +59 %, P < 0.05). IHCL and VLDL-TAG were not different between hypercaloric HFrD and HGlcD, but were increased compared to values observed with a weight maintenance diet. However, glucose led to a higher increase in IMCL than fructose.

  • Standardized protocol for a depletion of Intramyocellular Lipids (IMCL).
    NMR in biomedicine, 2010
    Co-Authors: Michael Ith, Roland Kreis, Philipp M. Huber, Andrea Egger, Jean-paul Schmid, Emanuel Christ, Chris Boesch
    Abstract:

    Intramyocellular Lipids (IMCL) are flexible fuel stores that are depleted by physical exercise and replenished by fat intake. IMCL or their degradation products are thought to interfere with insulin signaling thereby contributing to insulin resistance. From a practical point of view it is desirable to deplete IMCL prior to replenishing them. So far, it is not clear for how long and at which intensity subjects have to exercise in order to deplete IMCL. We therefore aimed at developing a standardized exercise protocol that is applicable to subjects over a broad range of exercise capacity and insulin sensitivity and allows measuring reliably reduced IMCL levels.Twelve male subjects, including four diabetes type 2 patients, with wide ranges of exercise capacity (VO(2)peak per total body weight 27.9-55.8 ml x kg(-1) x min(-1)), insulin sensitivity (glucose infusion rate per lean body mass 4.7-15.3 mg x min(-1) x kg(-1)), and BMI (21.7-31.5 kg x m(-2)), respectively, were enrolled. Using (1)H magnetic resonance spectroscopy ((1)H-MRS), IMCL was measured in m.tibialis anterior and m.vastus intermedius before and during a depletion protocol of a week, consisting of a moderate additional physical activity (1 h daily at 60% VO(2)peak) and modest low-fat (10-15%) diet.Absolute IMCL-levels were significantly reduced in both muscles during the first 3 days and stayed constant for the next 3 days of an identical diet/exercise-scheme. These reduced IMCL levels were independent of insulin sensitivity, yet a tendency to lower depleted IMCL levels has been observed in subjects with higher VO(2)peak.The proposed protocol is feasible in subjects with large differences in exercise capacity, insulin sensitivity, and BMI, leading to reduced IMCL levels that neither depend on the exact duration of the depletion protocol nor on insulin sensitivity. This allows for a standardized preparation of IMCL levels either for correlation with other physiological parameters or for replenishment studies.

Luc Tappy - One of the best experts on this subject based on the ideXlab platform.

  • effects of a short term overfeeding with fructose or glucose in healthy young males
    British Journal of Nutrition, 2010
    Co-Authors: Emilienne Tudor Ngo Sock, Chris Boesch, Roland Kreis, Michael Ith, Luc Tappy
    Abstract:

    Consumption of simple carbohydrates has markedly increased over the past decades, and may be involved in the increased prevalence in metabolic diseases. Whether an increased intake of fructose is specifically related to a dysregulation of glucose and lipid metabolism remains controversial. We therefore compared the effects of hypercaloric diets enriched with fructose (HFrD) or glucose (HGlcD) in healthy men. Eleven subjects were studied in a randomised order after 7 d of the following diets: (1) weight maintenance, control diet; (2) HFrD (3.5 g fructose/kg fat-free mass (ffm) per d, +35 % energy intake); (3) HGlcD (3.5 g glucose/kg ffm per d, +35 % energy intake). Fasting hepatic glucose output (HGO) was measured with 6,6-2H2-glucose. Intrahepatocellular Lipids (IHCL) and Intramyocellular Lipids (IMCL) were measured by 1H magnetic resonance spectroscopy. Both fructose and glucose increased fasting VLDL-TAG (HFrD: +59 %, P < 0.05; HGlcD: +31 %, P = 0.11) and IHCL (HFrD: +52 %, P < 0.05; HGlcD: +58 %, P = 0.06). HGO increased after both diets (HFrD: +5 %, P < 0.05; HGlcD: +5 %, P = 0.05). No change was observed in fasting glycaemia, insulin and alanine aminotransferase concentrations. IMCL increased significantly only after the HGlcD (HFrD: +24 %, NS; HGlcD: +59 %, P < 0.05). IHCL and VLDL-TAG were not different between hypercaloric HFrD and HGlcD, but were increased compared to values observed with a weight maintenance diet. However, glucose led to a higher increase in IMCL than fructose.

  • a 4 wk high fructose diet alters lipid metabolism without affecting insulin sensitivity or ectopic Lipids in healthy humans
    The American Journal of Clinical Nutrition, 2006
    Co-Authors: David Faeh, Eric Ravussin, Chris Boesch, Roland Kreis, Michael Ith, Peter Vermathen, Rodrigue Stettler, Luc Tappy
    Abstract:

    BACKGROUND: High fructose consumption is suspected to be causally linked to the epidemics of obesity and metabolic disorders. In rodents, fructose leads to insulin resistance and ectopic lipid deposition. In humans, the effects of fructose on insulin sensitivity remain debated, whereas its effect on ectopic Lipids has never been investigated. OBJECTIVE: We assessed the effect of moderate fructose supplementation on insulin sensitivity (IS) and ectopic Lipids in healthy male volunteers (n = 7). DESIGN: IS, intrahepatocellular Lipids (IHCL), and Intramyocellular Lipids (IMCL) were measured before and after 1 and 4 wk of a high-fructose diet containing 1.5 g fructose . kg body wt(-1) . d(-1). Adipose tissue IS was evaluated from nonesterified fatty acid suppression, hepatic IS from suppression of hepatic glucose output (6,6-2H2-glucose), and muscle IS from the whole-body glucose disposal rate during a 2-step hyperinsulinemic euglycemic clamp. IHCL and IMCL were measured by 1H magnetic resonance spectroscopy. RESULTS: Fructose caused significant (P < 0.05) increases in fasting plasma concentrations of triacylglycerol (36%), VLDL-triacylglycerol (72%), lactate (49%), glucose (5.5%), and leptin (48%) without any significant changes in body weight, IHCL, IMCL, or IS. IHCL were negatively correlated with triacylglycerol after 4 wk of the high-fructose diet (r = -0.78, P < 0.05). CONCLUSION: Moderate fructose supplementation over 4 wk increases plasma triacylglycerol and glucose concentrations without causing ectopic lipid deposition or insulin resistance in healthy humans.

  • Interaction Between Dietary Lipids and Physical Inactivity on Insulin Sensitivity and on Intramyocellular Lipids in Healthy Men
    Diabetes care, 2005
    Co-Authors: Rodrigue Stettler, Chris Boesch, Jacques Décombaz, Michael Ith, Kevin J. Acheson, Luc Tappy, Christophe Binnert
    Abstract:

    OBJECTIVE —To assess the effect of a possible interaction between dietary fat and physical inactivity on whole-body insulin sensitivity and Intramyocellular Lipids (IMCLs). RESEARCH DESIGN AND METHODS —Eight healthy male volunteers were studied on two occasions. After 2 days of an equilibrated diet and moderate physical activity, participants remained inactive (bed rest) for 60 h and consumed either a high–saturated fat (45% fat, of which ∼60% was saturated fat [BR-HF]) or a high-carbohydrate (70% carbohydrate [BR-HCHO]) diet. To evaluate the effect of a high-fat diet alone, six of the eight volunteers were restudied after a 2-day equilibrated diet followed by 60 h on a high–saturated fat diet and controlled physical activity (PA-HF). Insulin sensitivity was measured by hyperinsulinemic-euglycemic clamp and IMCL concentrations by 1 H-magnetic resonance spectroscopy. RESULTS —Insulin-mediated glucose disposal was decreased by BR-HF condition (−24 ± 6%, P P P P = 0.12) was similar to that during BR-HF, insulin-mediated glucose disposal (−7 ± 9%, NS) was not decreased. CONCLUSIONS —These data indicate that physical inactivity and a high–saturated fat diet may interact to reduce whole-body insulin sensitivity. IMCL content was influenced by dietary lipid and physical inactivity but was not directly associated with insulin resistance.

Patrick Schrauwen - One of the best experts on this subject based on the ideXlab platform.

  • High Oxidative Capacity Due to Chronic Exercise Training Attenuates Lipid-Induced Insulin Resistance
    2016
    Co-Authors: Esther Moonen-kornips, Matthijs K C Hesselink, Patrick Schrauwen
    Abstract:

    Fat accumulation in skeletal muscle combined with low mitochon-drial oxidative capacity is associated with insulin resistance (IR). Endurance-trained athletes, characterized by a high oxidative ca-pacity, have elevated Intramyocellular Lipids, yet are highly insulin sensitive. We tested the hypothesis that a high oxidative capacity could attenuate lipid-induced IR. Nine endurance-trained (age = 23.46 0.9 years; BMI = 21.26 0.6 kg/m2) and 10 untrained subjects (age = 21.96 0.9 years; BMI = 22.86 0.6 kg/m2) were included and underwent a clamp with either infusion of glycerol or intralipid. Muscle biopsies were taken to perform high-resolution respirome-try and protein phosphorylation/expression. Trained subjects had;32 % higher mitochondrial capacity and;22 % higher insulin sen-sitivity (P, 0.05 for both). Lipid infusion reduced insulin-stimulated glucose uptake by 63 % in untrained subjects (P, 0.05), whereas this effect was blunted in trained subjects (29%, P, 0.05). In untrained subjects, lipid infusion reduced oxidative and nonox

  • Chemical imaging of lipid droplets in muscle tissues using hyperspectral coherent Raman microscopy
    Histochemistry and Cell Biology, 2014
    Co-Authors: Billecke Nils, Matthijs K C Hesselink, Patrick Schrauwen, Gianluca Ragone, Bosma Madeleen, Eijkel Gert, Gemmink Anne, Philippe Leproux, Guillaume Huss, Mischa Bonn
    Abstract:

    The accumulation of Lipids in non-adipose tissues is attracting increasing attention due to its correlation with obesity. In muscle tissue, ectopic deposition of specific Lipids is further correlated with pathogenic development of insulin resistance and type 2 diabetes. Most Intramyocellular Lipids are organized into lipid droplets (LDs), which are metabolically active organelles. In order to better understand the putative role of LDs in pathogenesis, insight into both the location of LDs and nearby chemistry of muscle tissue is very useful. Here, we demonstrate the use of label-free coherent anti-Stokes Raman scattering (CARS) microscopy in combination with multivariate, chemometric analysis to visualize intracellular lipid accumulations in ex vivo muscle tissue. Consistent with our previous results, hyperspectral CARS microscopy showed an increase in LDs in tissues where LD proteins were overexpressed, and further chemometric analysis showed additional features morphologically (and chemically) similar to mitochondria that colocalized with LDs. CARS imaging is shown to be a very useful method for label-free stratification of ectopic fat deposition and cellular organelles in fresh tissue sections with virtually no sample preparation.

  • increased Intramyocellular Lipids but unaltered in vivo mitochondrial oxidative phosphorylation in skeletal muscle of adipose triglyceride lipase deficient mice
    American Journal of Physiology-endocrinology and Metabolism, 2012
    Co-Authors: Patrícia M. Nunes, Matthijs K C Hesselink, Patrick Schrauwen, Andor Veltien, H.f.g. Arnts, T. Van De Weijer, Cees J. Tack, Jan F C Glatz, Arend Heerschap
    Abstract:

    Adipose triglyceride lipase (ATGL) is a lipolytic enzyme that is highly specific for triglyceride hydrolysis. The ATGL-knockout mouse (ATGL−/−) accumulates lipid droplets in various tissues, includ...

  • PS14 - 71. Increased Intramyocellular Lipids, but normal muscular mitochondrial oxidative capacity in adipose triglyceride lipase deficient mice
    Nederlands Tijdschrift voor Diabetologie, 2011
    Co-Authors: Patrícia M. Nunes, Patrick Schrauwen, Andor Veltien, H.f.g. Arnts, T. Van De Weijer, Cees J. Tack, Arend Heerschap
    Abstract:

    Adipose triglyceride lipase (ATGL) is the rate-limiting enzyme of triglyceride hydrolysis and is mainly expressed in adipocytes and myocytes, thus ATGL-KO mice show abnormal triglyceride accumulation in those tissues. Intramyocellular Lipids (IMCL) are often used as biomarker of insulin resistance and type 2 diabetes, potentially reflecting lipotoxic effects on mitochondrial function. Whether IMCL accumulation per se has adverse effects on mitochondria is unclear. Therefore, we assessed IMCL levels and mitochondrial oxidative capacity of ATGL-KO mice in vivo with 1HMRS and gated-dynamic-31PMRS of contracting calf-muscles.

  • increased Intramyocellular lipid content but normal skeletal muscle mitochondrial oxidative capacity throughout the pathogenesis of type 2 diabetes
    The FASEB Journal, 2008
    Co-Authors: Henk M De Feyter, Matthijs K C Hesselink, Patrick Schrauwen, Klaas Nicolay, Ellen Lenaers, Sander M Houten, Ronald J A Wanders, Jeanine J. Prompers
    Abstract:

    Currently inherited or acquired skeletal muscle mitochondrial dysfunction is linked to dysregulated fatty acid metabolism, resulting in increased levels of Intramyocellular Lipids (IMCLs) and lipid intermediates, inducing insulin resistance. The present study aimed to clarify the order of changes in IMCL levels and skeletal muscle mitochondrial function during the development of type 2 diabetes in Zucker diabetic fatty (ZDF) rats. IMCL levels and skeletal muscle oxidative capacity were determined in vivo, using localized 1H magnetic resonance spectroscopy (MRS) and dynamic 31P MRS, respectively. In parallel, in vitro activities were measured from enzymes involved in fatty acid oxidation, the tricarboxylic acid cycle and the electron transport chain. Fa/fa ZDF rats were studied at 3 different ages corresponding to different stages of type 2 diabetes, whereas fa/+ rats served as controls. Fa/fa ZDF rats had higher IMCL contents than controls throughout the duration of the study. In vivo muscle oxidative cap...

Matthijs K C Hesselink - One of the best experts on this subject based on the ideXlab platform.

  • High Oxidative Capacity Due to Chronic Exercise Training Attenuates Lipid-Induced Insulin Resistance
    2016
    Co-Authors: Esther Moonen-kornips, Matthijs K C Hesselink, Patrick Schrauwen
    Abstract:

    Fat accumulation in skeletal muscle combined with low mitochon-drial oxidative capacity is associated with insulin resistance (IR). Endurance-trained athletes, characterized by a high oxidative ca-pacity, have elevated Intramyocellular Lipids, yet are highly insulin sensitive. We tested the hypothesis that a high oxidative capacity could attenuate lipid-induced IR. Nine endurance-trained (age = 23.46 0.9 years; BMI = 21.26 0.6 kg/m2) and 10 untrained subjects (age = 21.96 0.9 years; BMI = 22.86 0.6 kg/m2) were included and underwent a clamp with either infusion of glycerol or intralipid. Muscle biopsies were taken to perform high-resolution respirome-try and protein phosphorylation/expression. Trained subjects had;32 % higher mitochondrial capacity and;22 % higher insulin sen-sitivity (P, 0.05 for both). Lipid infusion reduced insulin-stimulated glucose uptake by 63 % in untrained subjects (P, 0.05), whereas this effect was blunted in trained subjects (29%, P, 0.05). In untrained subjects, lipid infusion reduced oxidative and nonox

  • Chemical imaging of lipid droplets in muscle tissues using hyperspectral coherent Raman microscopy
    Histochemistry and Cell Biology, 2014
    Co-Authors: Billecke Nils, Matthijs K C Hesselink, Patrick Schrauwen, Gianluca Ragone, Bosma Madeleen, Eijkel Gert, Gemmink Anne, Philippe Leproux, Guillaume Huss, Mischa Bonn
    Abstract:

    The accumulation of Lipids in non-adipose tissues is attracting increasing attention due to its correlation with obesity. In muscle tissue, ectopic deposition of specific Lipids is further correlated with pathogenic development of insulin resistance and type 2 diabetes. Most Intramyocellular Lipids are organized into lipid droplets (LDs), which are metabolically active organelles. In order to better understand the putative role of LDs in pathogenesis, insight into both the location of LDs and nearby chemistry of muscle tissue is very useful. Here, we demonstrate the use of label-free coherent anti-Stokes Raman scattering (CARS) microscopy in combination with multivariate, chemometric analysis to visualize intracellular lipid accumulations in ex vivo muscle tissue. Consistent with our previous results, hyperspectral CARS microscopy showed an increase in LDs in tissues where LD proteins were overexpressed, and further chemometric analysis showed additional features morphologically (and chemically) similar to mitochondria that colocalized with LDs. CARS imaging is shown to be a very useful method for label-free stratification of ectopic fat deposition and cellular organelles in fresh tissue sections with virtually no sample preparation.

  • increased Intramyocellular Lipids but unaltered in vivo mitochondrial oxidative phosphorylation in skeletal muscle of adipose triglyceride lipase deficient mice
    American Journal of Physiology-endocrinology and Metabolism, 2012
    Co-Authors: Patrícia M. Nunes, Matthijs K C Hesselink, Patrick Schrauwen, Andor Veltien, H.f.g. Arnts, T. Van De Weijer, Cees J. Tack, Jan F C Glatz, Arend Heerschap
    Abstract:

    Adipose triglyceride lipase (ATGL) is a lipolytic enzyme that is highly specific for triglyceride hydrolysis. The ATGL-knockout mouse (ATGL−/−) accumulates lipid droplets in various tissues, includ...

  • increased Intramyocellular lipid content but normal skeletal muscle mitochondrial oxidative capacity throughout the pathogenesis of type 2 diabetes
    The FASEB Journal, 2008
    Co-Authors: Henk M De Feyter, Matthijs K C Hesselink, Patrick Schrauwen, Klaas Nicolay, Ellen Lenaers, Sander M Houten, Ronald J A Wanders, Jeanine J. Prompers
    Abstract:

    Currently inherited or acquired skeletal muscle mitochondrial dysfunction is linked to dysregulated fatty acid metabolism, resulting in increased levels of Intramyocellular Lipids (IMCLs) and lipid intermediates, inducing insulin resistance. The present study aimed to clarify the order of changes in IMCL levels and skeletal muscle mitochondrial function during the development of type 2 diabetes in Zucker diabetic fatty (ZDF) rats. IMCL levels and skeletal muscle oxidative capacity were determined in vivo, using localized 1H magnetic resonance spectroscopy (MRS) and dynamic 31P MRS, respectively. In parallel, in vitro activities were measured from enzymes involved in fatty acid oxidation, the tricarboxylic acid cycle and the electron transport chain. Fa/fa ZDF rats were studied at 3 different ages corresponding to different stages of type 2 diabetes, whereas fa/+ rats served as controls. Fa/fa ZDF rats had higher IMCL contents than controls throughout the duration of the study. In vivo muscle oxidative cap...

  • regional variations in Intramyocellular lipid concentration correlate with muscle fiber type distribution in rat tibialis anterior muscle
    Magnetic Resonance in Medicine, 2006
    Co-Authors: Henk M De Feyter, Matthijs K C Hesselink, Patrick Schrauwen, Gert Schaart, Klaas Nicolay, Jeanine J. Prompers
    Abstract:

    1H MR spectroscopy (MRS) has proved to be a valuable noninvasive tool to measure Intramyocellular Lipids (IMCL) in research focused on insulin resistance and type II diabetes in both humans and rodents. An important determinant of IMCL is the muscle fiber type, since oxidative type I fibers can contain up to three times more IMCL than glycolytic type II muscle fibers. Because these different muscle fiber types are inhomogeneously distributed in rodent muscle, in the present study we investigated the distribution of IMCL within the rat tibialis anterior muscle (TA) in vivo using single-voxel 1H MRS along with the muscle fiber distribution in the TA ex vivo determined from immunohistological assays. IMCL levels in the TA differed by up to a factor of 3 depending on the position of the voxel. The distribution of IMCL over the TA cross section was not random, but emerged in a pattern similar to the distribution of the predominantly oxidative muscle fiber types. Dietary interventions, such as high-fat feeding and 15 hr of fasting, did not significantly change this typical fiber type-dependent pattern of IMCL content. These results stress the importance of voxel positioning when single-voxel 1H MRS is used to study IMCL in rodent muscle. Magn Reson Med, 2006. © 2006 Wiley-Liss, Inc.