Year: 2014
Type: article
Abstract: Hyperglycemia in the hospitalized setting is common, especially in patients that receive nutritional support either continuously or intermittently. As the liver and muscle are the major sites of glucose disposal, we hypothesized their metabolic adaptations are sensitive to the pattern of nutrient delivery. Chronically catheterized, well-controlled depancreatized dogs were placed on one of three isocaloric diets: regular chow diet once daily (Chow) or a simple nutrient diet (ND) that was given either once daily (ND-4) or infused continuously (ND-C). Intraportal insulin was infused to maintain euglycemia. After 5 days net hepatic (NHGU) and muscle (MGU) glucose uptake and oxidation were assessed at euglycemia (120 mg/dl) and hyperglycemia (200 mg/dl) in the presence of basal insulin. While hyperglycemia increased both NHGU and MGU in Chow, NHGU was amplified in both groups receiving ND. The increase was associated with enhanced activation of glycogen synthase, glucose oxidation and suppression of pyruvate dehydrogenase kinase-4 (PDK-4). Accelerated glucose-dependent muscle glucose uptake was only evident with ND-C. This was associated with a decrease in PDK-4 expression and an increase in AMP-activated protein kinase (AMPK) phosphorylation. Interestingly, ND-C markedly increased hepatic FGF-21 expression. Thus, augmentation of carbohydrate disposal in the liver, as opposed to the muscle, is not dependent on the pattern of nutrient delivery.
Source: PLoS ONE
Institution: Vanderbilt University
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,382
Awards: Impact of Inflammation on the Control of Muscle Glucose Uptake, G117257630, G1221739687, G1352409854, Nutrition Infection and Hepatic Carbohydrate Metabolism, G2304076072, G33365108, Vanderbilt Mouse Metabolic Phenotyping Center, G5436572433, Nutrition Infection and Hepatic Carbohydrate Metabolism, G8366546091, Diabetes Research and Training Center, G9000052735, G9000063507, Multidisciplinary Training in Molecular Endocrinology, G9000269960, Vanderbilt Diabetes Research Center
OpenAlex ID: W1968673444