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Marco-Rius I, von Morze C, Sriram R, Cao P, Chang GY, Milshteyn E, Bok RA, Ohliger MA, Pearce D, Kurhanewicz J, Larson PEZ, Vigneron DB, Merritt M. Monitoring acute metabolic changes in the liver and kidneys induced by fructose and glucose using hyperpolarized [2- 13 C]dihydroxyacetone. Magn Reson Med 2016; 77:65-73. [PMID: 27859575 DOI: 10.1002/mrm.26525] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/02/2016] [Accepted: 10/03/2016] [Indexed: 01/18/2023]
Abstract
PURPOSE To investigate acute changes in glucose metabolism in liver and kidneys in vivo after a bolus injection of either fructose or glucose, using hyperpolarized [2-13 C]dihydroxyacetone. METHODS Spatially registered, dynamic, multislice MR spectroscopy was acquired for the metabolic products of [2-13 C]dihydroxyacetone in liver and kidneys. Metabolism was probed in 13 fasted rats at three time points: 0, 70, and 140 min. At 60 min, rats were injected intravenously with fructose (n = 5) or glucose (n = 4) at 0.8 g/kg to initiate acute response. Controls (n = 4) did not receive a carbohydrate challenge. RESULTS Ten minutes after fructose infusion, levels of [2-13 C]phosphoenolpyruvate and [2-13 C]glycerol-3-phosphate halved in liver: 51% (P = 0.0010) and 47% (P = 0.0001) of baseline, respectively. Seventy minutes later, levels returned to baseline. The glucose challenge did not alter the signals significantly, nor did repeated administration of the dihydroxyacetone imaging bolus. In kidneys, no statistically significant changes were detected after sugar infusion other than a 20% increase of the glycerol-3-phosphate signal between 10 and 80 min after fructose injection (P = 0.0028). CONCLUSION Hyperpolarized [2-13 C]dihydroxyacetone detects a real-time, transient metabolic response of the liver to an acute fructose challenge. Observed effects possibly include ATP depletion and changes in the unlabeled pool sizes of glycolytic intermediates. Magn Reson Med 77:65-73, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Irene Marco-Rius
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Cornelius von Morze
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Renuka Sriram
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Peng Cao
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Gene-Yuan Chang
- Department of Medicine, Division of Nephrology, University of California San Francisco, San Francisco, California, USA
| | - Eugene Milshteyn
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Robert A Bok
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Michael A Ohliger
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - David Pearce
- Department of Medicine, Division of Nephrology, University of California San Francisco, San Francisco, California, USA
| | - John Kurhanewicz
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Peder E Z Larson
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Daniel B Vigneron
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, USA
| | - Matthew Merritt
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida, USA
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Proof of principle: hydration by low-osmolar mannitol-glucose solution alleviates undesirable renal effects of an iso-osmolar contrast medium in rats. Invest Radiol 2012; 47:240-6. [PMID: 22353855 DOI: 10.1097/rli.0b013e31823acbaa] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Saline infusion is widely used to prevent contrast media (CM)-induced acute kidney injury, because it fosters diuresis. Osmodiuretics have a stronger diuretic effect than saline, yet previous trials indicate that osmodiuretic mannitol tends to promote rather than to prevent CM-induced acute kidney injury. However, these studies used hypertonic mannitol solutions that will result in rebound volume contraction. We hypothesize that combining the osmodiuretic effects of a nonhypertonic mannitol solution with sustained volume expansion alleviates undesirable renal effects of CM. MATERIALS AND METHODS Forty-four anesthetized rats were studied by 4 protocols. Urine flow rate, urine viscosity, and glomerular filtration rate (GFR) were measured. Intravenous infusions of hydration solutions were initiated 60 minutes before CM administration and continued throughout the observation period. Hydration by a 3.2% mannitol and 3.2% glucose solution infused at 12 mL/kg per hour (Mannit-Gluc regimen) was compared with a standard regimen of isotonic saline at 4 mL/kg per hour (NaCl regimen); greater infusion rates are required for the Mannit-Gluc regimen because of the profound diuretic effect of mannitol. Two CM were studied: iso-osmolar iodixanol (320 mg I/mL) and low-osmolar iopromide (370 mg I/mL), they were administered as 1.5-mL bolus injection into the thoracic aorta. RESULTS The Mannit-Gluc regimen resulted in higher urine flow rates than the standard NaCl regimen, yet maintained a good volume status. By virtue of its stronger diuretic effect, the Mannit-Gluc regimen greatly diminished the increase in urine viscosity and completely prevented the transient decrease in GFR caused by iodixanol with the NaCl regimen. After iopromide, the differences between the hydration regimens were much less, as iopromide increased urine flow rates much more than iodixanol, thus resulting in a much smaller increase in viscosity than iodixanol and no decrease in GFR even with the NaCl regimen. CONCLUSION This proof of principle study shows that a hydration regimen that combines the osmodiuretic effect of a low-osmolar mannitol-glucose solution with sustained volume expansion is effective in reducing high urine viscosity and preventing GFR reduction caused by iso-osmolar iodixanol. For low-osmolar CM, the beneficial effects seem negligible, because these compounds per se exert greater osmodiuretic action.
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