Intramyocellular Ceramides: Subcellular Concentrations and Fractional De Novo Synthesis in Postabsorptive Humans
Autor: | Jin Ook Chung, Agnieszka Blachnio-Zabielska, Kazanna C. Hames, Michael D. Jensen, Christina Koutsari |
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Jazyk: | angličtina |
Rok vydání: | 2017 |
Předmět: |
0301 basic medicine
Adult Male medicine.medical_specialty Ceramide Time Factors Endocrinology Diabetes and Metabolism Biopsy Palmitates 030209 endocrinology & metabolism Triglycerides blood Fatty Acids Nonesterified Ceramides 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Insulin resistance Sarcolemma Myofibrils Tandem Mass Spectrometry Internal medicine Internal Medicine medicine Humans Insulin Muscle Skeletal Triglycerides Muscle Cells Insulin blood Triglyceride Skeletal muscle Fasting medicine.disease Healthy Volunteers De novo synthesis 030104 developmental biology medicine.anatomical_structure Endocrinology Metabolism chemistry lipids (amino acids peptides and proteins) Female Plasma insulin Insulin Resistance Chromatography Liquid |
Zdroj: | Diabetes |
ISSN: | 1939-327X 0012-1797 |
Popis: | We investigated the relationship between insulin resistance markers and subsarcolemmal (SS) and intramyofibrillar (IMF) ceramide concentrations, as well as the contribution of plasma palmitate (6.5-h infusion of [U-13C]palmitate) to intramyocellular ceramides. Seventy-six postabsorptive men and women had muscle biopsies 1.5, 6.5, and 24 h after starting the tracer infusion. Concentrations and enrichment of muscle ceramides were measured by liquid chromatography-tandem mass spectrometry. We found that HOMA of insulin resistance, plasma insulin, and triglyceride concentrations were positively correlated with SS C16:0 and C18:1 ceramide, but not SS C14:0-Cer, C20:0-Cer, C24:0-Cer, and C24:1-Cer concentrations; IMF ceramide concentrations were not correlated with any metabolic parameters. The fractional contribution of plasma palmitate to 16:0 ceramide was greater in SS than IMF (SS, 18.2% vs. IMF, 8.7%; P = 0.0006). Plasma insulin concentrations correlated positively with the fractional contribution of plasma palmitate to SS 16:0 ceramide. The fractional contribution of plasma palmitate to intramyocellular SS 16:0 ceramide was positively correlated with SS C16:0 ceramide concentrations (γ = 0.435; P = 0.002). We conclude that skeletal muscle SS ceramides, especially C16 to C18 chain lengths and the de novo synthesis of intramyocellular ceramide from plasma palmitate are associated with markers of insulin resistance. |
Databáze: | OpenAIRE |
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