1. Sources of hepatic glycogen synthesis in mice fed with glucose or fructose as the sole dietary carbohydrate.
- Author
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Jarak I, Barosa C, Martins FO, Silva JCP, Santos C, Belew GD, Rito J, Viegas I, Teixeira J, Oliveira PJ, and Jones JG
- Subjects
- Animal Feed, Animals, Blood Glucose analysis, Dietary Sucrose metabolism, Magnetic Resonance Spectroscopy, Male, Mice, Mice, Inbred C57BL, Water, Dietary Carbohydrates, Fructose metabolism, Glucose analogs & derivatives, Glucose metabolism, Glycogenolysis, Liver metabolism, Liver Glycogen metabolism
- Abstract
Purpose: The positional analysis of hepatic glycogen enrichment from deuterated water (
2 H2 O) by2 H NMR has been applied previously to resolve the contributions of glucose and fructose to glycogen synthesis in rodents fed a high sucrose diet. To further validate this method, this analysis was applied to mice fed with synthetic diets whose carbohydrate components consisted solely of either glucose or fructose., Methods: Eight glucose-fed and 12 fructose-fed mice were given2 H2 O followed by ad libitum feeding overnight. Mice were then euthanized, hepatic glycogen was isolated and derivatized to monoacetone glucose, and2 H-enrichment of positions 2, 5, and 6S were measured by2 H NMR. From these data, the fraction of overnight glycogen appearance from the direct pathway and/or glycogen cycling and indirect pathway were estimated. Indirect pathway fractions were resolved into Krebs cycle and triose-phosphate sources-the latter including contributions from fructose metabolism., Results: After overnight feeding, the fraction of overnight glycogen appearance derived from direct pathway and/or glycogen cycling in glucose-fed-mice was 63 ± 1%. For the indirect pathway, Krebs cycle and triose-phosphate sources contributed 22 ± 1% and 15 ± 1%, respectively. For fructose-fed-mice, glycogen appearance was dominated by triose-phosphate sources (60 ± 2%) with lesser contributions from Krebs cycle (14 ± 1%) and direct and/or glycogen cycling (26 ± 2%)., Conclusions:2 H NMR analysis of hepatic glycogen2 H enrichment from2 H2 O provides realistic profiles of dietary glucose and fructose contributions to hepatic glycogen synthesis in mice fed with diets containing 1 or the other sugar as the sole carbohydrate source., (© 2018 International Society for Magnetic Resonance in Medicine.)- Published
- 2019
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