Glucose Metabolism
Metabolic Solutions offers project design assistance and a mass spectrometry service to help researchers study glucose metabolism using stable isotope methods. The primed constant infusion of stable isotope labeled glucose has been extensively validated as a reliable approach to quantifying glucose kinetics. This approach can be used to explore whole body glucose homeostasis under various perturbations such as exogenous infusions of glucose and insulin. Sensitive methods for measuring labeled glucose in plasma have been developed to permit quantification with 50-100 µl of plasma. Thus, these studies can be performed relatively easily in newborns.
New Research: Measurement of Insulin Resistance with the Glucose Disposal Test
Insulin resistance is an important risk factor for the development of type 2 diabetes. The gold standard for measuring insulin resistance is the euglycemic-hyperinsulinemic glucose clamp developed by DeFronso. The clamp method involves intravenous infusions of labeled glucose with and without insulin, while maintaining glucose levels. The rate of labeled glucose appearance in plasma is measured and the amount of glucose disposed is calculated. Unlabeled glucose is infused into the subject to maintain the glucose levels. The test requires a clinical research center for the infusion studies, plus the studies are labor intensive and costly. Beysen et al. have validated the deuterated-glucose disposal test against the euglycemic-hyperinsulinemic glucose clamp. The glucose disposal test consists of an oral 6,6-D2-glucose challenge dose followed by measurement of heavy water (2H2O) for 3 hours. The production of 2H2O represents whole-body glycolytic disposal of the glucose load.
Applications
| Application | Tracer Examples | Reference |
|---|---|---|
| Glucose Kinetics | 6,6-D2-glucose | Effect of IGF-1 on glucose kinetics in healthy adults |
| Euglycemic Clamps | 6,6-D2-glucose | Insulin-stimulated carbohydrate metabolism |
| Glucose Disposal Rate | 6,6-D2-glucose | Insulin Resistance and the glucose disposal test |
| Glucose Oxidation | [U-13C6]-glucose | Glucose oxidation with moderate intensity exercise |
List of Glucose Metabolism Services
- Hepatic endogenous production
- Glucose disposal rates
- Glucose flux measurements
- Oxidation
- Gluconeogenesis
If you need protocol information on how to conduct glucose metabolism tracer studies, the following technical paper is available: Stable Isotope Tracer Experiments with Glucose
Published Glucose Metabolism Studies Analyzed By Metabolic Solutions
- Phillips, S.M., H.J. Green, M.A., Tarnopolsky, and S.M. Grant. Decreased glucose turnover after short-term training is unaccompanied by changes in muscle oxidative potential. Am J Physiol. 269(32):E222-E230, 1995.
"This study investigated the hypothesis that training-induced reduction in exercise blood glucose utilization can occur independently of increases in muscle mitochondrial potential." - Landau, B.R., Wahren, J., Chandramouli, V., Schumann, W.C., Ekberg, K., Kalhan, S.C. Use of 2H2O for Estimating rates of Gluconeogenesis. J. Clin. Invest. 95: 272-178, 1995.
"A method is introduced for estimating the contribution of gluconeogenesis to glucose production. 2H2O is administered orally to achieve 0.5% deuterium enrichment in body water." - Chandramouli, V., Ekber, K., Schumann, W.C., Kalhan, S.C., Wahren, J., Landau, B.R. Quantifying gluconeogenesis during fasting. Am. J. Physiol. 273(36):E1209-E1215, 1997.
"The use of 2H2O in estimating gluconeogenesis' contribution to glucose production (%GNG) was examined during progressive fasting in three groups of healthy subjects."
