1. Effects of acute exercise on lipid content and dietary lipid uptake in liver and skeletal muscle of lean and diabetic rats
- Author
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Luc J. C. van Loon, Klaas Nicolay, Jeanine J. Prompers, Albert K. Groen, Sharon Janssens, Richard A. M. Jonkers, Nutrition and Movement Sciences, RS: NUTRIM - R3 - Chronic inflammatory disease and wasting, RS: NUTRIM - HB/BW section A, Center for Liver, Digestive and Metabolic Diseases (CLDM), and Lifestyle Medicine (LM)
- Subjects
Blood Glucose ,Male ,Magnetic Resonance Spectroscopy ,Physiology ,Endocrinology, Diabetes and Metabolism ,Adipose tissue ,Skeletal muscle ,FATTY-ACID-METABOLISM ,SDG 3 – Goede gezondheid en welzijn ,chemistry.chemical_compound ,Random Allocation ,IN-VIVO ,INSULIN-RESISTANCE ,Carbon Isotopes ,ENDURANCE-TRAINED MALES ,Diabetes ,Organ Size ,MAGNETIC-RESONANCE-SPECTROSCOPY ,Lipids ,Absorption, Physiological ,INTRAMYOCELLULAR LIPIDS ,medicine.anatomical_structure ,ADIPOSE-TISSUE ,Liver ,Organ Specificity ,medicine.medical_specialty ,Dietary lipid ,Motor Activity ,Insulin resistance ,SDG 3 - Good Health and Well-being ,Physiology (medical) ,Diabetes mellitus ,Internal medicine ,medicine ,Animals ,Obesity ,Intramyocellular lipids ,Muscle, Skeletal ,Exercise ,Fatty acid metabolism ,business.industry ,Lipid metabolism ,medicine.disease ,Dietary Fats ,LIPASE GENE-EXPRESSION ,Rats, Zucker ,MODERATE-INTENSITY EXERCISE ,Endocrinology ,chemistry ,Diabetes Mellitus, Type 2 ,INDUCED HEPATIC STEATOSIS ,Insulin Resistance ,business ,Energy Metabolism - Abstract
Insulin resistance is associated with ectopic lipid accumulation. Physical activity improves insulin sensitivity, but the impact of exercise on lipid handling in insulin-resistant tissues remains to be elucidated. The present study characterizes the effects of acute exercise on lipid content and dietary lipid partitioning in liver and skeletal muscle of lean and diabetic rats by use of magnetic resonance spectroscopy (MRS). After baseline measurements, rats were randomized to exercise or no-exercise groups. A subset of animals was subjected to MRS directly after 1 h of treadmill running for measurement of total intrahepatocellular lipid (IHCL) and intramyocellular lipid (IMCL) content ( n = 7 lean and diabetic rats). The other animals were administered13C-labeled lipids orally after treadmill visit (with or without exercise) followed by MRS measurements after 4 and 24 h to determine the13C enrichment of IHCL and IMCL ( n = 8 per group). Total IHCL and IMCL content were fivefold higher in diabetic vs. lean rats ( P < 0.001). Exercise did not significantly affect IHCL content but reduced IMCL by 25 ± 7 and 33 ± 4% in lean and diabetic rats ( P < 0.05), respectively. Uptake of dietary lipids in liver and muscle was 2.3-fold greater in diabetic vs. lean rats ( P < 0.05). Prior exercise did not significantly modulate dietary lipid uptake into muscle, but in liver of both lean and diabetic rats, lipid uptake was 44% reduced after acute exercise ( P < 0.05). In conclusion, IMCL but not IHCL represents a viable substrate source during exercise in both lean and diabetic rats, and exercise differentially affects dietary lipid uptake in muscle and liver.
- Published
- 2015