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Peper CJ, Kilgore MD, Jiang Y, Xiu Y, Xia W, Wang Y, Shi M, Zhou D, Dumont AS, Wang X, Liu N. Tracing the path of disruption: 13C isotope applications in traumatic brain injury-induced metabolic dysfunction. CNS Neurosci Ther 2024; 30:e14693. [PMID: 38544365 PMCID: PMC10973562 DOI: 10.1111/cns.14693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 02/25/2024] [Accepted: 03/12/2024] [Indexed: 05/14/2024] Open
Abstract
Cerebral metabolic dysfunction is a critical pathological hallmark observed in the aftermath of traumatic brain injury (TBI), as extensively documented in clinical investigations and experimental models. An in-depth understanding of the bioenergetic disturbances that occur following TBI promises to reveal novel therapeutic targets, paving the way for the timely development of interventions to improve patient outcomes. The 13C isotope tracing technique represents a robust methodological advance, harnessing biochemical quantification to delineate the metabolic trajectories of isotopically labeled substrates. This nuanced approach enables real-time mapping of metabolic fluxes, providing a window into the cellular energetic state and elucidating the perturbations in key metabolic circuits. By applying this sophisticated tool, researchers can dissect the complexities of bioenergetic networks within the central nervous system, offering insights into the metabolic derangements specific to TBI pathology. Embraced by both animal studies and clinical research, 13C isotope tracing has bolstered our understanding of TBI-induced metabolic dysregulation. This review synthesizes current applications of isotope tracing and its transformative potential in evaluating and addressing the metabolic sequelae of TBI.
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Affiliation(s)
- Charles J. Peper
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
| | - Mitchell D. Kilgore
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
| | - Yinghua Jiang
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
| | - Yuwen Xiu
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
| | - Winna Xia
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
| | - Yingjie Wang
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
| | - Mengxuan Shi
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
| | - Di Zhou
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
| | - Aaron S. Dumont
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
| | - Xiaoying Wang
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
- Neuroscience Program, Tulane Brain InstituteTulane UniversityNew OrleansLouisianaUSA
| | - Ning Liu
- Clinical Neuroscience Research Center, Departments of Neurosurgery and NeurologyTulane University School of MedicineNew OrleansLouisianaUSA
- Neuroscience Program, Tulane Brain InstituteTulane UniversityNew OrleansLouisianaUSA
- Tulane University Translational Sciences InstituteNew OrleansLouisianaUSA
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2
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Metabolism of Exogenous [2,4- 13C]β-Hydroxybutyrate following Traumatic Brain Injury in 21-22-Day-Old Rats: An Ex Vivo NMR Study. Metabolites 2022; 12:metabo12080710. [PMID: 36005582 PMCID: PMC9414923 DOI: 10.3390/metabo12080710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 07/22/2022] [Accepted: 07/26/2022] [Indexed: 02/04/2023] Open
Abstract
Traumatic brain injury (TBI) is leading cause of morbidity in young children. Acute dysregulation of oxidative glucose metabolism within the first hours after injury is a hallmark of TBI. The developing brain relies on ketones as well as glucose for energy. Thus, the aim of this study was to determine the metabolism of ketones early after TBI injury in the developing brain. Following the controlled cortical impact injury model of TBI, 21-22-day-old rats were infused with [2,4-13C]β-hydroxybutyrate during the acute (4 h) period after injury. Using ex vivo 13C-NMR spectroscopy, we determined that 13C-β-hydroxybutyrate (13C-BHB) metabolism was increased in both the ipsilateral and contralateral sides of the brain after TBI. Incorporation of the label was significantly higher in glutamate than glutamine, indicating that 13C-BHB metabolism was higher in neurons than astrocytes in both sham and injured brains. Our results show that (i) ketone metabolism was significantly higher in both the ipsilateral and contralateral sides of the injured brain after TBI; (ii) ketones were extensively metabolized by both astrocytes and neurons, albeit higher in neurons; (iii) the pyruvate recycling pathway determined by incorporation of the label from the metabolism of 13C-BHB into lactate was upregulated in the immature brain after TBI.
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3
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Bartnik-Olson BL, Ding D, Howe J, Shah A, Losey T. Glutamate metabolism in temporal lobe epilepsy as revealed by dynamic proton MRS following the infusion of [U 13-C] glucose. Epilepsy Res 2017; 136:46-53. [PMID: 28763722 DOI: 10.1016/j.eplepsyres.2017.07.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 07/04/2017] [Accepted: 07/18/2017] [Indexed: 12/27/2022]
Abstract
Focal metabolic dysfunction commonly observed in temporal lobe epilepsy (TLE), and is associated with the development of medical intractability and neurocognitive deficits. It has not been established if this dysfunction is due to cell loss or biochemical dysfunction in metabolic pathways. To explore this question, dynamic 1H MRS following an infusion of [U13- C] glucose was performed to measure glutamate (Glu) metabolism. Subjects (n=6) showed reduced Glu levels (p<0.01) in the ipsilateral mesial temporal lobe (MTL) compared with controls (n=4). However, the rate of 13C incorporation into Glu did not differ between those with epilepsy and controls (p=0.77). This suggests that reduced Glu concentrations in the region of the seizure focus are not due to disruptions in metabolic pathways, but may instead be due to neuronal loss or simplification.
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Affiliation(s)
| | - Daniel Ding
- School of Medicine, Loma Linda University, Loma Linda CA, United States
| | - John Howe
- School of Medicine, Loma Linda University, Loma Linda CA, United States
| | - Amul Shah
- School of Medicine, Loma Linda University, Loma Linda CA, United States
| | - Travis Losey
- Department of Neurology, Loma Linda University, Loma Linda CA, United States.
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4
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Wolahan SM, Hirt D, Braas D, Glenn TC. Role of Metabolomics in Traumatic Brain Injury Research. Neurosurg Clin N Am 2016; 27:465-72. [PMID: 27637396 DOI: 10.1016/j.nec.2016.05.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Metabolomics is an important member of the omics community in that it defines which small molecules may be responsible for disease states. This article reviews the essential principles of metabolomics from specimen preparation, chemical analysis, to advanced statistical methods. Metabolomics in traumatic brain injury has so far been underutilized. Future metabolomics-based studies focused on the diagnoses, prognoses, and treatment effects need to be conducted across all types of traumatic brain injury.
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Affiliation(s)
- Stephanie M Wolahan
- UCLA Brain Injury Research Center, David Geffen School of Medicine at UCLA, 10833 Le Conte Ave, Los Angeles, CA 90095, USA; Department of Neurosurgery, David Geffen School of Medicine at UCLA, 300 Stein Plaza, Los Angeles, CA 90095-6901, USA
| | - Daniel Hirt
- UCLA Brain Injury Research Center, David Geffen School of Medicine at UCLA, 10833 Le Conte Ave, Los Angeles, CA 90095, USA; Department of Neurosurgery, David Geffen School of Medicine at UCLA, 300 Stein Plaza, Los Angeles, CA 90095-6901, USA
| | - Daniel Braas
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, 570 Westwood Plaza, Los Angeles, CA 90095-1735, USA; UCLA Metabolomics and Proteomics Center, 570 Westwood Plaza, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Thomas C Glenn
- UCLA Brain Injury Research Center, David Geffen School of Medicine at UCLA, 10833 Le Conte Ave, Los Angeles, CA 90095, USA; Department of Neurosurgery, David Geffen School of Medicine at UCLA, 300 Stein Plaza, Los Angeles, CA 90095-6901, USA.
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5
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Sinha S, Raheja A, Samson N, Bhoi S, Selvi A, Sharma P, Sharma BS. Blood mitochondrial enzymatic assay as a predictor of long-term outcome in severe traumatic brain injury. J Clin Neurosci 2016; 30:31-38. [DOI: 10.1016/j.jocn.2015.10.051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 10/23/2015] [Accepted: 10/25/2015] [Indexed: 02/07/2023]
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6
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Dalecki M, Albines D, Macpherson A, Sergio LE. Prolonged cognitive-motor impairments in children and adolescents with a history of concussion. Concussion 2016; 1:CNC14. [PMID: 30202556 PMCID: PMC6094154 DOI: 10.2217/cnc-2016-0001] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Accepted: 02/26/2016] [Indexed: 01/01/2023] Open
Abstract
Aim: We investigated whether children and adolescents with concussion history show cognitive–motor integration (CMI) deficits. Method: Asymptomatic children and adolescents with concussion history (n = 50; mean 12.84 years) and no history (n = 49; mean: 11.63 years) slid a cursor to targets using their finger on a dual-touch-screen laptop; target location and motor action were not aligned in the CMI task. Results: Children and adolescents with concussion history showed prolonged CMI deficits, in that their performance did not match that of no history controls until nearly 2 years postevent. Conclusion: These CMI deficits may be due to disruptions in fronto-parietal networks, contributing to an increased vulnerability to further injury. Current return-to-play assessments that do not test CMI may not fully capture functional abilities postconcussion.
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Affiliation(s)
- Marc Dalecki
- School of Kinesiology & Health Science, York University, Toronto, Ontario, Canada.,Centre for Vision Research, York University, Toronto, Ontario, Canada.,School of Kinesiology & Health Science, York University, Toronto, Ontario, Canada.,Centre for Vision Research, York University, Toronto, Ontario, Canada
| | - David Albines
- School of Kinesiology & Health Science, York University, Toronto, Ontario, Canada.,School of Kinesiology & Health Science, York University, Toronto, Ontario, Canada
| | - Alison Macpherson
- School of Kinesiology & Health Science, York University, Toronto, Ontario, Canada.,York University Sport Medicine Team, York University, Toronto, Ontario, Canada.,School of Kinesiology & Health Science, York University, Toronto, Ontario, Canada.,York University Sport Medicine Team, York University, Toronto, Ontario, Canada
| | - Lauren E Sergio
- School of Kinesiology & Health Science, York University, Toronto, Ontario, Canada.,Centre for Vision Research, York University, Toronto, Ontario, Canada.,York University Sport Medicine Team, York University, Toronto, Ontario, Canada.,School of Kinesiology & Health Science, York University, Toronto, Ontario, Canada.,Centre for Vision Research, York University, Toronto, Ontario, Canada.,York University Sport Medicine Team, York University, Toronto, Ontario, Canada
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7
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Zafardoost P, Ghasemi AA, Salehpour F, Piroti C, Ziaeii E. Evaluation of the Effect of Glibenclamide in Patients With Diffuse Axonal Injury Due to Moderate to Severe Head Trauma. Trauma Mon 2016; 21:e25113. [PMID: 28184360 PMCID: PMC5292034 DOI: 10.5812/traumamon.25113] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 03/13/2015] [Accepted: 03/29/2015] [Indexed: 02/07/2023] Open
Abstract
Background Traumatic brain injury (TBI) is a major health problem worldwide. Secondary injuries after TBI, including diffuse axonal injury (DAI) often occur, and proper treatments are needed in this regard. It has been shown that glibenclamide could reduce secondary brain damage after experimental TBI and improve outcomes. Objectives We aim to evaluate the role of glibenclamide on the short-term outcome of patients with DAI due to moderate to severe TBI. Patients and Methods In this controlled randomized clinical trial, 40 patients with moderate to severe TBI were assigned to glibenclamide (n = 20) and control (n = 20) groups. Six hours after admission the intervention group received 1.25 mg glibenclamide every 12 hours. The Glasgow coma scale (GCS) was administered at admission, in the first 24 and 48 hours, at one week post-trauma and at discharge. The Glasgow outcome scale (GOS) was also administered at discharge. All results were evaluated and compared between groups. Results Patients treated with glibenclamide compared to the control group had a significantly better GCS score one week post-trauma (P = 0.003) and at discharge (P = 0.004), as well as a better GOS score at discharge (P = 0.001). The glibenclamide group also had a shorter length of hospital stay compared to the control group (P = 0.03). In the control group, two patients (10%) died during the first week post-trauma, but there was no mortality in the glibenclamide group (P = 0.48). Conclusions Treatment with glibenclamide in patients with DAI due to moderate to severe TBI significantly improves short-term outcomes.
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Affiliation(s)
- Peyman Zafardoost
- Neurosurgery Department, Urmia University of Medical Sciences, Urmia, IR Iran
- Corresponding author: Peyman Zafardoost, Neurosurgery Department, Urmia University of Medical Sciences, Urmia, IR Iran. Tel: +98-4433485324, E-mail:
| | - Amir Abbas Ghasemi
- Neurosurgery Department, Urmia University of Medical Sciences, Urmia, IR Iran
| | - Firooz Salehpour
- Neurosurgery Department, Urmia University of Medical Sciences, Urmia, IR Iran
| | - Chia Piroti
- Neurosurgery Department, Urmia University of Medical Sciences, Urmia, IR Iran
| | - Ehsan Ziaeii
- Neurosurgery Department, Urmia University of Medical Sciences, Urmia, IR Iran
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8
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McKenna MC, Scafidi S, Robertson CL. Metabolic Alterations in Developing Brain After Injury: Knowns and Unknowns. Neurochem Res 2015; 40:2527-43. [PMID: 26148530 PMCID: PMC4961252 DOI: 10.1007/s11064-015-1600-7] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/10/2015] [Accepted: 05/02/2015] [Indexed: 12/21/2022]
Abstract
Brain development is a highly orchestrated complex process. The developing brain utilizes many substrates including glucose, ketone bodies, lactate, fatty acids and amino acids for energy, cell division and the biosynthesis of nucleotides, proteins and lipids. Metabolism is crucial to provide energy for all cellular processes required for brain development and function including ATP formation, synaptogenesis, synthesis, release and uptake of neurotransmitters, maintaining ionic gradients and redox status, and myelination. The rapidly growing population of infants and children with neurodevelopmental and cognitive impairments and life-long disability resulting from developmental brain injury is a significant public health concern. Brain injury in infants and children can have devastating effects because the injury is superimposed on the high metabolic demands of the developing brain. Acute injury in the pediatric brain can derail, halt or lead to dysregulation of the complex and highly regulated normal developmental processes. This paper provides a brief review of metabolism in developing brain and alterations found clinically and in animal models of developmental brain injury. The metabolic changes observed in three major categories of injury that can result in life-long cognitive and neurological disabilities, including neonatal hypoxia-ischemia, pediatric traumatic brain injury, and brain injury secondary to prematurity are reviewed.
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Affiliation(s)
- Mary C McKenna
- Department of Pediatrics and Program in Neuroscience, University of Maryland School of Medicine, 655 W. Baltimore St., Room 13-019, Baltimore, MD, 21201, USA.
| | - Susanna Scafidi
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Courtney L Robertson
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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9
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Brown JA, Dalecki M, Hughes C, Macpherson AK, Sergio LE. Cognitive-motor integration deficits in young adult athletes following concussion. BMC Sports Sci Med Rehabil 2015; 7:25. [PMID: 26491541 PMCID: PMC4612424 DOI: 10.1186/s13102-015-0019-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 10/09/2015] [Indexed: 01/05/2023]
Abstract
BACKGROUND The ability to perform visually-guided motor tasks requires the transformation of visual information into programmed motor outputs. When the guiding visual information does not align spatially with the motor output, the brain processes rules to integrate the information for an appropriate motor response. Here, we look at how performance on such tasks is affected in young adult athletes with concussion history. METHODS Participants displaced a cursor from a central to peripheral targets on a vertical display by sliding their finger along a touch sensitive screen in one of two spatial planes. The addition of a memory component, along with variations in cursor feedback increased task complexity across conditions. RESULTS Significant main effects between participants with concussion history and healthy controls without concussion history were observed in timing and accuracy measures. Importantly, the deficits were distinctly more pronounced for participants with concussion history compared to healthy controls, especially when the brain had to control movements having two levels of decoupling between vision and action. A discriminant analysis correctly classified athletes with a history of concussion based on task performance with an accuracy of 94 %, despite the majority of these athletes being rated asymptomatic by current standards. CONCLUSIONS These findings correspond to our previous work with adults at risk of developing dementia, and support the use of cognitive motor integration as an enhanced assessment tool for those who may have mild brain dysfunction. Such a task may provide a more sensitive metric of performance relevant to daily function than what is currently in use, to assist in return to play/work/learn decisions.
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Affiliation(s)
- Jeffrey A Brown
- School of Kinesiology and Health Science, York University, 357 Bethune College, 4700 Keele Street, Toronto, M3J 1P3 ON Canada
| | - Marc Dalecki
- School of Kinesiology and Health Science, York University, 357 Bethune College, 4700 Keele Street, Toronto, M3J 1P3 ON Canada ; Centre for Vision Research, York University, Toronto, Canada
| | - Cindy Hughes
- School of Kinesiology and Health Science, York University, 357 Bethune College, 4700 Keele Street, Toronto, M3J 1P3 ON Canada ; York University Sport Medicine Team, York University, Toronto, Canada
| | - Alison K Macpherson
- School of Kinesiology and Health Science, York University, 357 Bethune College, 4700 Keele Street, Toronto, M3J 1P3 ON Canada ; York University Sport Medicine Team, York University, Toronto, Canada
| | - Lauren E Sergio
- School of Kinesiology and Health Science, York University, 357 Bethune College, 4700 Keele Street, Toronto, M3J 1P3 ON Canada ; Centre for Vision Research, York University, Toronto, Canada ; York University Sport Medicine Team, York University, Toronto, Canada ; Southlake Regional Health Centre, Newmarket, ON Canada
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10
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McKenna MC, Scafidi S, Robertson CL. Metabolic Alterations in Developing Brain After Injury: Knowns and Unknowns. Neurochem Res 2015. [PMID: 26148530 DOI: 10.1007/s11064‐015‐1600‐7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Brain development is a highly orchestrated complex process. The developing brain utilizes many substrates including glucose, ketone bodies, lactate, fatty acids and amino acids for energy, cell division and the biosynthesis of nucleotides, proteins and lipids. Metabolism is crucial to provide energy for all cellular processes required for brain development and function including ATP formation, synaptogenesis, synthesis, release and uptake of neurotransmitters, maintaining ionic gradients and redox status, and myelination. The rapidly growing population of infants and children with neurodevelopmental and cognitive impairments and life-long disability resulting from developmental brain injury is a significant public health concern. Brain injury in infants and children can have devastating effects because the injury is superimposed on the high metabolic demands of the developing brain. Acute injury in the pediatric brain can derail, halt or lead to dysregulation of the complex and highly regulated normal developmental processes. This paper provides a brief review of metabolism in developing brain and alterations found clinically and in animal models of developmental brain injury. The metabolic changes observed in three major categories of injury that can result in life-long cognitive and neurological disabilities, including neonatal hypoxia-ischemia, pediatric traumatic brain injury, and brain injury secondary to prematurity are reviewed.
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Affiliation(s)
- Mary C McKenna
- Department of Pediatrics and Program in Neuroscience, University of Maryland School of Medicine, 655 W. Baltimore St., Room 13-019, Baltimore, MD, 21201, USA.
| | - Susanna Scafidi
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Courtney L Robertson
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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11
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Fructose Alters Intermediary Metabolism of Glucose in Human Adipocytes and Diverts Glucose to Serine Oxidation in the One-Carbon Cycle Energy Producing Pathway. Metabolites 2015; 5:364-85. [PMID: 26087138 PMCID: PMC4495377 DOI: 10.3390/metabo5020364] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 06/09/2015] [Indexed: 12/29/2022] Open
Abstract
Increased consumption of sugar and fructose as sweeteners has resulted in the utilization of fructose as an alternative metabolic fuel that may compete with glucose and alter its metabolism. To explore this, human Simpson-Golabi-Behmel Syndrome (SGBS) preadipocytes were differentiated to adipocytes in the presence of 0, 1, 2.5, 5 or 10 mM of fructose added to a medium containing 5 mM of glucose representing the normal blood glucose concentration. Targeted tracer [1,2-13C2]-d-glucose fate association approach was employed to examine the influence of fructose on the intermediary metabolism of glucose. Increasing concentrations of fructose robustly increased the oxidation of [1,2-13C2]-d-glucose to 13CO2 (p < 0.000001). However, glucose-derived 13CO2 negatively correlated with 13C labeled glutamate, 13C palmitate, and M+1 labeled lactate. These are strong markers of limited tricarboxylic acid (TCA) cycle, fatty acid synthesis, pentose cycle fluxes, substrate turnover and NAD+/NADP+ or ATP production from glucose via complete oxidation, indicating diminished mitochondrial energy metabolism. Contrarily, a positive correlation was observed between glucose-derived 13CO2 formed and 13C oleate and doses of fructose which indicate the elongation and desaturation of palmitate to oleate for storage. Collectively, these results suggest that fructose preferentially drives glucose through serine oxidation glycine cleavage (SOGC pathway) one-carbon cycle for NAD+/NADP+ production that is utilized in fructose-induced lipogenesis and storage in adipocytes.
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12
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Glycolysis and the pentose phosphate pathway after human traumatic brain injury: microdialysis studies using 1,2-(13)C2 glucose. J Cereb Blood Flow Metab 2015; 35:111-20. [PMID: 25335801 PMCID: PMC4294402 DOI: 10.1038/jcbfm.2014.177] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 08/16/2014] [Accepted: 09/08/2014] [Indexed: 02/02/2023]
Abstract
Increased 'anaerobic' glucose metabolism is observed after traumatic brain injury (TBI) attributed to increased glycolysis. An alternative route is the pentose phosphate pathway (PPP), which generates putatively protective and reparative molecules. To compare pathways we employed microdialysis to perfuse 1,2-(13)C2 glucose into the brains of 15 TBI patients and macroscopically normal brain in six patients undergoing surgery for benign tumors, and to simultaneously collect products for nuclear magnetic resonance (NMR) analysis. (13)C enrichment for glycolytic 2,3-(13)C2 lactate was the median 5.4% (interquartile range (IQR) 4.6-7.5%) in TBI brain and 4.2% (2.4-4.4%) in 'normal' brain (P<0.01). The ratio of PPP-derived 3-(13)C lactate to glycolytic 2,3-(13)C2 lactate was median 4.9% (3.6-8.2%) in TBI brain and 6.7% (6.3-8.9%) in 'normal' brain. An inverse relationship was seen for PPP-glycolytic lactate ratio versus PbtO2 (r=-0.5, P=0.04) in TBI brain. Thus, glycolytic lactate production was significantly greater in TBI than 'normal' brain. Several TBI patients exhibited PPP-lactate elevation above the 'normal' range. There was proportionally greater PPP-derived lactate production with decreasing PbtO2. The study raises questions about the roles of the PPP and glycolysis after TBI, and whether they can be manipulated to achieve a better outcome. This study is the first direct comparison of glycolysis and PPP in human brain.
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13
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Varma V, Boros LG, Nolen GT, Chang CW, Wabitsch M, Beger RD, Kaput J. Metabolic fate of fructose in human adipocytes: a targeted 13C tracer fate association study. Metabolomics 2015; 11:529-544. [PMID: 25972768 PMCID: PMC4419153 DOI: 10.1007/s11306-014-0716-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 07/18/2014] [Indexed: 11/12/2022]
Abstract
The development of obesity is becoming an international problem and the role of fructose is unclear. Studies using liver tissue and hepatocytes have contributed to the understanding of fructose metabolism. Excess fructose consumption also affects extra hepatic tissues including adipose tissue. The effects of fructose on human adipocytes are not yet fully characterized, although in vivo studies have noted increased adiposity and weight gain in response to fructose sweetened-beverages. In order to understand and predict the metabolic responses of adipocytes to fructose, this study examined differentiating and differentiated human adipocytes in culture, exposed to a range of fructose concentrations equivalent to that reported in blood after consuming fructose. A stable isotope based dynamic profiling method using [U-13C6]-d-fructose tracer was used to examine the metabolism and fate of fructose. A targeted stable isotope tracer fate association method was used to analyze metabolic fluxes and flux surrogates with exposure to escalating fructose concentration. This study demonstrated that fructose stimulates anabolic processes in adipocytes robustly, including glutamate and de novo fatty acid synthesis. Furthermore, fructose also augments the release of free palmitate from fully differentiated adipocytes. These results imply that in the presence of fructose, the metabolic response of adipocytes in culture is altered in a dose dependent manner, particularly favoring increased glutamate and fatty acid synthesis and release, warranting further in vivo studies.
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Affiliation(s)
- Vijayalakshmi Varma
- Division of Systems Biology, National Center for Toxicological Research, FDA, 3900 NCTR Road, Jefferson, AR 72079 USA
| | - László G. Boros
- SiDMAP LLC, Los Angeles, CA 90064 USA
- Los Angeles Biomedical Research Institute (LABIOMED), Harbor-UCLA Medical Center, Torrance, CA 90502 USA
- Department of Pediatrics, Harbor-UCLA Medical Center, Torrance, CA 90502 USA
| | - Greg T. Nolen
- Division of Systems Biology, National Center for Toxicological Research, FDA, 3900 NCTR Road, Jefferson, AR 72079 USA
| | - Ching-Wei Chang
- Division of Bioinformatics and Biostatistics, National Center for Toxicological Research, Jefferson, AR 72079 USA
| | - Martin Wabitsch
- Division of Pediatric Endocrinology and Diabetology, University of Ulm, Ulm, Germany
| | - Richard D. Beger
- Division of Systems Biology, National Center for Toxicological Research, FDA, 3900 NCTR Road, Jefferson, AR 72079 USA
| | - Jim Kaput
- Division of Systems Biology, National Center for Toxicological Research, FDA, 3900 NCTR Road, Jefferson, AR 72079 USA
- Systems Nutrition and Health, Nestle Institute of Health Sciences, Lausanne, Switzerland
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14
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Bramlett HM, Dietrich WD. Long-Term Consequences of Traumatic Brain Injury: Current Status of Potential Mechanisms of Injury and Neurological Outcomes. J Neurotrauma 2014; 32:1834-48. [PMID: 25158206 DOI: 10.1089/neu.2014.3352] [Citation(s) in RCA: 296] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Traumatic brain injury (TBI) is a significant clinical problem with few therapeutic interventions successfully translated to the clinic. Increased importance on the progressive, long-term consequences of TBI have been emphasized, both in the experimental and clinical literature. Thus, there is a need for a better understanding of the chronic consequences of TBI, with the ultimate goal of developing novel therapeutic interventions to treat the devastating consequences of brain injury. In models of mild, moderate, and severe TBI, histopathological and behavioral studies have emphasized the progressive nature of the initial traumatic insult and the involvement of multiple pathophysiological mechanisms, including sustained injury cascades leading to prolonged motor and cognitive deficits. Recently, the increased incidence in age-dependent neurodegenerative diseases in this patient population has also been emphasized. Pathomechanisms felt to be active in the acute and long-term consequences of TBI include excitotoxicity, apoptosis, inflammatory events, seizures, demyelination, white matter pathology, as well as decreased neurogenesis. The current article will review many of these pathophysiological mechanisms that may be important targets for limiting the chronic consequences of TBI.
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Affiliation(s)
- Helen M Bramlett
- The Miami Project to Cure Paralysis/Department of Neurological Surgery, University of Miami Miller School of Medicine , Miami, Florida
| | - W Dalton Dietrich
- The Miami Project to Cure Paralysis/Department of Neurological Surgery, University of Miami Miller School of Medicine , Miami, Florida
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Lama S, Auer RN, Tyson R, Gallagher CN, Tomanek B, Sutherland GR. Lactate storm marks cerebral metabolism following brain trauma. J Biol Chem 2014; 289:20200-8. [PMID: 24849602 DOI: 10.1074/jbc.m114.570978] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Brain metabolism is thought to be maintained by neuronal-glial metabolic coupling. Glia take up glutamate from the synaptic cleft for conversion into glutamine, triggering glial glycolysis and lactate production. This lactate is shuttled into neurons and further metabolized. The origin and role of lactate in severe traumatic brain injury (TBI) remains controversial. Using a modified weight drop model of severe TBI and magnetic resonance (MR) spectroscopy with infusion of (13)C-labeled glucose, lactate, and acetate, the present study investigated the possibility that neuronal-glial metabolism is uncoupled following severe TBI. Histopathology of the model showed severe brain injury with subarachnoid and hemorrhage together with glial cell activation and positive staining for Tau at 90 min post-trauma. High resolution MR spectroscopy of brain metabolites revealed significant labeling of lactate at C-3 and C-2 irrespective of the infused substrates. Increased (13)C-labeled lactate in all study groups in the absence of ischemia implied activated astrocytic glycolysis and production of lactate with failure of neuronal uptake (i.e. a loss of glial sensing for glutamate). The early increase in extracellular lactate in severe TBI with the injured neurons rendered unable to pick it up probably contributes to a rapid progression toward irreversible injury and pan-necrosis. Hence, a method to detect and scavenge the excess extracellular lactate on site or early following severe TBI may be a potential primary therapeutic measure.
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Affiliation(s)
- Sanju Lama
- From the Department of Clinical Neurosciences and the Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 2T9, Canada and
| | - Roland N Auer
- the Hôpital Ste-Justine, Département de Pathologie, Université de Montréal, Montreal, Québec H3T 1C5, Canada
| | - Randy Tyson
- From the Department of Clinical Neurosciences and the Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 2T9, Canada and
| | - Clare N Gallagher
- From the Department of Clinical Neurosciences and the Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 2T9, Canada and
| | - Boguslaw Tomanek
- From the Department of Clinical Neurosciences and the Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 2T9, Canada and
| | - Garnette R Sutherland
- From the Department of Clinical Neurosciences and the Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 2T9, Canada and
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Yee JK, Lee WNP, Ross MG, Lane RH, Han G, Vega J, Desai M. Peroxisome proliferator-activated receptor gamma modulation and lipogenic response in adipocytes of small-for-gestational age offspring. Nutr Metab (Lond) 2012; 9:62. [PMID: 22726273 PMCID: PMC3495639 DOI: 10.1186/1743-7075-9-62] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Accepted: 06/14/2012] [Indexed: 01/30/2023] Open
Abstract
Background Small-for-gestational age (SGA) at birth increases risk of development of adult obesity and insulin resistance. A model of SGA rat offspring has been shown to exhibit increased adipose tissue expression of a key adipogenic transcription factor, peroxisome proliferator-activated receptor gamma (PPARγ), and increased fatty acid de novo synthesis during the nursing period, prior to onset of obesity. PPARγ agonists have been studied for potential use in the prevention of insulin resistance. Moreover, SGA adipocytes exhibit age-dependent differences in lipogenesis as mediated by PPARγ. The effects of PPARγ modulators on lipogenic gene expression and de novo lipogenesis on the age-dependent changes in SGA adipocytes are not known. The objectives of this study were: 1) to determine the adipogenic and lipogenic potential in SGA adipocytes at postnatal day 1 (p1) and day 21 (p21), 2) to determine how the PPARγ activator- and repressor-ligands affect the lipogenic potential, and 3) to determine the fatty acid metabolic response to PPARγ activator-ligand treatment. Methods Primary adipocyte cultures from p1 and p21 SGA and Control male offspring were established from a known maternal food-restriction model of SGA. Cell proliferation and Oil Red O (ORO) staining were quantified. Adipocytes were treated with increasing doses of rosiglitazone or bisphenol-A diglycidyl ether (BADGE). PPARγ and SREBP1 protein expression were determined. De novo lipogenesis with rosiglitazone treatment at p21 was studied using 50% U13C-glucose and gas chromatography/mass spectrometry. Results At p1 and p21, SGA demonstrated increased cell proliferation and increased ORO staining. At p21, SGA demonstrated increased lipogenic gene expression and increased glucose-mediated fatty acid de novo synthesis compared with Controls. In response to rosiglitazone, SGA adipocytes further increased glucose utilization for fatty acid synthesis. SGA lipogenic gene expression demonstrated resistance to BADGE treatment. Conclusions SGA adipocytes exhibit an enhanced adipogenic and lipogenic potential in early postnatal life. By p21, SGA demonstrated resistance to PPARγ repressor-ligand treatment, and selective response to high dose PPARγ activator-ligand treatment in adipogenic and lipogenic gene expression. p21 SGA adipocytes revealed increased fatty acid de novo synthesis through a complex relationship with glucose metabolism.
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Affiliation(s)
- Jennifer K Yee
- Department of Pediatrics, Division of Endocrinology, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, David Geffen School of Medicine at UCLA, 1000 West Carson Street, Harbor Box 446, Torrance, CA 90509, USA.
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Allen BS, Buckberg GD. Studies of isolated global brain ischaemia: I. Overview of irreversible brain injury and evolution of a new concept - redefining the time of brain death. Eur J Cardiothorac Surg 2012; 41:1132-7. [PMID: 22398465 DOI: 10.1093/ejcts/ezr315] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Despite advanced cardiac life support (ACLS), the mortality from sudden death after cardiac arrest is 85-95%, and becomes nearly 100% if ischaemia is prolonged, as occurs following unwitnessed arrest. Moreover, 33-50% of survivors following ACLS after witnessed arrest develop significant neurological dysfunction, and this rises to nearly 100% in the rare survivors of unwitnessed arrest. Although, whole body (cardiac) survival improves to 30% following recent use of emergency cardiopulmonary bypass, sustained neurological dysfunction remains a devastating and unresolved problem. Our studies suggest that both brain and whole body damage reflect an ischaemic/reperfusion injury that follows the present reperfusion methods that use normal blood, which we term 'uncontrolled reperfusion'. In contrast, we have previously introduced the term 'controlled reperfusion', which denotes controlling both the conditions (pressure, flow and temperature) as well as the composition (solution) of the reperfusate. Following prolonged ischaemia of the heart, lung and lower extremity, controlled reperfusion resulted in tissue recovery after ischaemic intervals previously thought to produce irreversible cellular injury. These observations underlie the current hypothesis that controlled reperfusion will become an effective treatment of the otherwise lethal injury of prolonged brain ischaemia, such as with unwitnessed arrest, and we tested this after 30 min of normothermic global brain ischaemia. This review, and the subsequent three studies will describe the evolution of the concept that controlled reperfusion will restore neurological function to the brain following prolonged (30 min) ischaemia. To provide a familiarity and rationale for these studies, this overview reviews the background and current treatment of sudden death, the concepts of controlled reperfusion, recent studies in the brain during whole body ischaemia, and then summarizes the three papers in this series on a new brain ischaemia model that endorses our hypothesis that controlled reperfusion allows complete neurological recovery following 30 min of normothermic global brain ischaemia. These findings may introduce innovative management approaches for sudden death, and perhaps stroke, because the brain is completely salvageable following ischaemic times thought previously to produce infarction.
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Affiliation(s)
- Bradley S Allen
- Department of Surgery, University of California, Los Angeles, CA, USA.
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Sonko BJ, Schmitt TC, Guo L, Shi Q, Boros LG, Leakey JEA, Beger RD. Assessment of usnic acid toxicity in rat primary hepatocytes using ¹³C isotopomer distribution analysis of lactate, glutamate and glucose. Food Chem Toxicol 2011; 49:2968-74. [PMID: 21802472 DOI: 10.1016/j.fct.2011.07.047] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Revised: 07/07/2011] [Accepted: 07/10/2011] [Indexed: 11/19/2022]
Abstract
The lichen metabolite usnic acid (UA) has been promoted as a dietary supplement for weight loss, although cases of hepatotoxicity have been reported. Here we evaluated UA-associated hepatotoxicity in vitro using isolated rat hepatocytes. We measured cell viability and ATP content to evaluate UA induced cytotoxicity and applied (13)C isotopomer distribution measuring techniques to gain a better understanding of glucose metabolism during cytotoxicity. The cells were exposed to 0, 1, 5 or 10 μM UA concentrations for 2, 6 or 24h. Aliquots of media were collected at the end of these time periods and the (13)C mass isotopomer distribution determined for CO(2), lactate, glucose and glutamate. The 1 μM UA exposure did not appear to cause significant change in cell viability compared to controls. However, the 5 and 10 μM UA concentrations significantly reduced cell viability as exposure time increased. Similar results were obtained for ATP depletion experiments. The 1 and 5 μM UA doses suggest increased oxidative phosphorylation. Conversely, oxidative phosphorylation and gluconeogenesis were dramatically inhibited by 10 μM UA. Augmented oxidative phosphorylation at the lower UA concentrations may be an adaptive response by the cells to compensate for diminished mitochondrial function.
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Affiliation(s)
- Bakary J Sonko
- Division of Systems Biology, National Center for Toxicological Research, US FDA, Jefferson, AR 72079, USA
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Bartnik-Olson BL, Oyoyo U, Hovda DA, Sutton RL. Astrocyte oxidative metabolism and metabolite trafficking after fluid percussion brain injury in adult rats. J Neurotrauma 2010; 27:2191-202. [PMID: 20939699 DOI: 10.1089/neu.2010.1508] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Despite various lines of evidence pointing to the compartmentation of metabolism within the brain, few studies have reported the effect of a traumatic brain injury (TBI) on neuronal and astrocyte compartments and/or metabolic trafficking between these cells. In this study we used ex vivo ¹³C NMR spectroscopy following an infusion of [1-¹³C] glucose and [1,2-¹³C₂] acetate to study oxidative metabolism in neurons and astrocytes of sham-operated and fluid percussion brain injured (FPI) rats at 1, 5, and 14 days post-surgery. FPI resulted in a decrease in the ¹³C glucose enrichment of glutamate in neurons in the injured hemisphere at day 1. In contrast, enrichment of glutamine in astrocytes from acetate was not significantly decreased at day 1. At day 5 the ¹³C enrichment of glutamate and glutamine from glucose in the injured hemisphere of FPI rats did not differ from sham levels, but glutamine derived from acetate metabolism in astrocytes was significantly increased. The ¹³C glucose enrichment of the C3 position of glutamate (C3) in neurons was significantly decreased ipsilateral to FPI at day 14, whereas the enrichment of glutamine in astrocytes had returned to sham levels at this time point. These findings indicate that the oxidative metabolism of glucose is reduced to a greater extent in neurons compared to astrocytes following a FPI. The increased utilization of acetate to synthesize glutamine, and the acetate enrichment of glutamate via the glutamate-glutamine cycle, suggests an integral protective role for astrocytes in maintaining metabolic function following TBI-induced impairments in glucose metabolism.
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Affiliation(s)
- Brenda L Bartnik-Olson
- Brain Injury Research Center, David Geffen School of Medicine at the University of California-Los Angeles, Los Angeles, California, USA.
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Schutz PW, Wong PKH, O'Kusky J, Innis SM, Stockler S. Effects of d-3-hydroxybutyrate treatment on hypoglycemic coma in rat pups. Exp Neurol 2010; 227:180-7. [PMID: 21056562 DOI: 10.1016/j.expneurol.2010.10.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2010] [Revised: 09/26/2010] [Accepted: 10/26/2010] [Indexed: 11/16/2022]
Abstract
d-3-Hydroxybutyrate (3OHB) is an alternative energy substrate for the brain during hypoglycemia, especially in infancy. Knowledge of the capacity and limits of 3OHB to compensate for cerebral glucose depletion during hypoglycemia in developing brain is important for its potential clinical use, but is scarce. We studied the effect of 3OHB treatment during insulin-induced hypoglycemia in 13-day-old rat pups. 3OHB treatment resulted in increased 3OHB plasma levels in hypoglycemic animals (3-4mM vs. 0.5-1mM untreated), and delayed the onset of clinical coma by 70min and of burst-suppression coma by 90min. 3OHB treated animals did not survive after resuscitation with glucose, compared to 80% survival of untreated hypoglycemic pups. Cleaved-caspase-3 immunohistochemistry and double labeling studies demonstrated a 20-fold increase of apoptotic mature oligodendrocytes in white matter of 3OHB treated animals. 3OHB treatment delays the onset of clinical and burst-suppression coma during hypoglycemia, but the prolonged duration of hypoglycemia is associated with increased mortality after resuscitation and cellular white matter injury.
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Affiliation(s)
- Peter W Schutz
- Department of Pediatrics, British Columbia Children's Hospital and University of British Columbia, Vancouver, BC, Canada.
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Fukushima M, Lee SM, Moro N, Hovda DA, Sutton RL. Metabolic and histologic effects of sodium pyruvate treatment in the rat after cortical contusion injury. J Neurotrauma 2010; 26:1095-110. [PMID: 19594384 DOI: 10.1089/neu.2008.0771] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This study determined the effects of intraperitoneal sodium pyruvate (SP) treatment on the levels of circulating fuels and on cerebral microdialysis levels of glucose (MD(glc)), lactate (MD(lac)), and pyruvate (MD(pyr)), and the effects of SP treatment on neuropathology after left cortical contusion injury (CCI) in rats. SP injection (1000 mg/kg) 5 min after sham injury (Sham-SP) or CCI (CCI-SP) significantly increased arterial pyruvate (p < 0.005) and lactate (p < 0.001) compared to that of saline-treated rats with CCI (CCI-Sal). Serum glucose also increased significantly in CCI-SP compared to that in CCI-Sal rats (p < 0.05), but not in Sham-SP rats. MD(pyr) was not altered after CCI-Sal, whereas MD(lac) levels within the cerebral cortex significantly increased bilaterally (p < 0.05) and those for MD(glc) decreased bilaterally (p < 0.05). MD(pyr) levels increased significantly in both Sham-SP and CCI-SP rats (p < 0.05 vs. CCI-Sal) and were higher in left/injured cortex of the CCI-SP group (p < 0.05 vs. sham-SP). In CCI-SP rats the contralateral MD(lac) decreased below CCI-Sal levels (p < 0.05) and the ipsilateral MD(glc) levels exceeded those of CCI-Sal rats (p < 0.05). Rats with a single low (500 mg/kg) or high dose (1000 mg/kg) SP treatment had fewer damaged cortical cells 6 h post-CCI than did saline-treated rats (p < 0.05), but three hourly injections of SP (1000 mg/kg) were needed to significantly reduce contusion volume 2 weeks after CCI. Thus, a single intraperitoneal SP treatment increases circulating levels of three potential brain fuels, attenuates a CCI-induced reduction in extracellular glucose while increasing extracellular levels of pyruvate, but not lactate, and can attenuate cortical cell damage occurring within 6 h of injury. Enduring (2 week) neuronal protection was achieved only with multiple SP treatments within the first 2 h post-CCI, perhaps reflecting the need for additional fuel throughout the acute period of increased metabolic demands induced by CCI.
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Affiliation(s)
- Masamichi Fukushima
- Brain Injury Research Center, David Geffen School of Medicine at UCLA, Los Angeles, California 90095-7039, USA
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Riazi R, Khairallah M, Cameron JM, Pencharz PB, Des Rosiers C, Robinson BH. Probing pyruvate metabolism in normal and mutant fibroblast cell lines using 13C-labeled mass isotopomer analysis and mass spectrometry. Mol Genet Metab 2009; 98:349-55. [PMID: 19640754 DOI: 10.1016/j.ymgme.2009.06.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2009] [Revised: 06/25/2009] [Accepted: 06/26/2009] [Indexed: 10/20/2022]
Abstract
Fibroblast cell lines are frequently used to diagnose genetic mitochondrial defects in children. The effect of enzyme deficiency on overall flux rate through metabolic pathways is, however, not generally considered. We have transposed an experimental paradigm that was developed for isolated perfused organs using (13)C-labeled substrates and (13)C-isotopomer analysis to probe pyruvate mitochondrial metabolism in cultured human fibroblast cell lines with normal or genetically mutant pyruvate decarboxylation (PDC) or carboxylation (PC) activity. Cells were incubated with 1mM [U-(13)C]pyruvate, and the (13)C-molar percent enrichment (MPE) of intracellular pyruvate, citrate, malate (as a surrogate of oxaloacetate) and aspartate was assessed by mass spectrometry. We estimated various flux ratios relevant to metabolic pathways involved in energy production, namely pyruvate formation, PDC, PC, and citrate recycling in the citric acid cycle (CAC). In all cell lines, exogenous pyruvate was predominately decarboxylated (PC/PDC ratios 0.01-0.3). PC-deficient cell lines displayed an expected negligible contribution of PC flux to oxaloacetate formation for citrate synthesis (PC/CS), which was associated with a greater contribution of PDC to acetyl-CoA formation (PDC/CS), and greater recycling of (13)C-labeled citrate into the CAC. In PDH-deficient cell lines, metabolic flux alterations were most apparent in cells with more than 50% reduction in enzyme activity. This led to an unexpected lower PC/CS flux ratio, while the PDC/CS flux ratio was unchanged. These data illustrate the usefulness of this approach in identifying unexpected metabolic consequences of genetic defects related to pyruvate metabolism.
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Affiliation(s)
- Roya Riazi
- Genetic and Genomic Biology, Research Institute, The Hospital for Sick Children, 555 University Avenue, Toronto, Ont., Canada
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Abstract
Significant fluctuations in serum glucose levels accompany the stress response of surgery or acute injury and may be associated with vascular or neurologic morbidity. Maintenance of euglycemia with intensive insulin therapy (IIT) continues to be investigated as a therapeutic intervention to decrease morbidity associated with derangements in glucose metabolism. Hypoglycemia is a common side effect of IIT with potential for significant morbidity, especially in the neurologically injured patient. Differences in cerebral versus systemic glucose metabolism, the time course of cerebral response to injury, and heterogeneity of pathophysiology in neurosurgical patient populations are important to consider in evaluating the risks and benefits of IIT. While extremes of glucose levels are to be avoided, there are little data to support specific use of IIT for maintenance of euglycemia in the perioperative management of neurosurgical patients. Existing data are summarized and reviewed in this context.
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Affiliation(s)
- Joshua H Atkins
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
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Marklund N, Sihver S, Hovda DA, Långström B, Watanabe Y, Ronquist G, Bergström M, Hillered L. Increased Cerebral Uptake of [18F]Fluoro-Deoxyglucose but not [1-14C]Glucose Early following Traumatic Brain Injury in Rats. J Neurotrauma 2009; 26:1281-93. [DOI: 10.1089/neu.2008.0827] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Niklas Marklund
- Department of Neuroscience, Unit of Neurosurgery, Uppsala University CSO, Imanet, and Uppsala Applied Science Laboratory, Uppsala, Sweden
| | - Sven Sihver
- Department of Neuroscience, Unit of Pharmacology, Uppsala University CSO, Imanet, and Uppsala Applied Science Laboratory, Uppsala, Sweden
| | - David A. Hovda
- UCLA Brain Injury Research Center, Departments of Neurosurgery and Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, University of California–Los Angeles, Los Angeles, California
| | - Bengt Långström
- Department of Biochemistry and Organic Chemistry, Uppsala University CSO, Imanet, and Uppsala Applied Science Laboratory, Uppsala, Sweden
| | - Yasuyoshi Watanabe
- Department of Neuroscience, Osaka Bioscience Institute, Osaka, Japan
- Department of Physiology, Osaka City University, Osaka, Japan
| | - Gunnar Ronquist
- Department of Medical Sciences, Biochemical Structure And Function, Uppsala University CSO, Imanet, and Uppsala Applied Science Laboratory, Uppsala, Sweden
| | - Mats Bergström
- Department of Biochemistry and Organic Chemistry, Uppsala University CSO, Imanet, and Uppsala Applied Science Laboratory, Uppsala, Sweden
| | - Lars Hillered
- Department of Neuroscience, Unit of Neurosurgery, Uppsala University CSO, Imanet, and Uppsala Applied Science Laboratory, Uppsala, Sweden
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Marklund N, Sihver S, Hovda D, Långström B, Watanabe Y, Ronquist G, Bergström M, Hillered L. INCREASED CEREBRAL UPTAKE OF [18F]FLUORO-DEOXYGLUCOSE BUT NOT [1-14C]GLUCOSE EARLY FOLLOWING TRAUMATIC BRAIN INJURY IN RATS. J Neurotrauma 2009. [DOI: 10.1089/neu.2008-0827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Xing G, Ren M, Watson WD, Watson WA, O'Neill JT, O'Neil JT, Verma A. Traumatic brain injury-induced expression and phosphorylation of pyruvate dehydrogenase: a mechanism of dysregulated glucose metabolism. Neurosci Lett 2009; 454:38-42. [PMID: 19429050 DOI: 10.1016/j.neulet.2009.01.047] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Revised: 12/11/2008] [Accepted: 01/15/2009] [Indexed: 10/21/2022]
Abstract
Dysregulated brain glucose metabolism and lactate accumulation are seen following traumatic brain injury (TBI). The underlying molecular mechanism is poorly understood. Pyruvate dehydrogenase (PDH), the rate-limiting enzyme coupling cytosolic glycolysis to mitochondrial citric acid cycle, plays a critical role in maintaining homeostasis of brain glucose metabolism. PDH activity is maintained by the expression of its E1alpha1 subunit 1 (PDHE1alpha1) and is inhibited by the phosphorylation of PDHE1alpha1 (p-PDHE1alpha1). We hypothesized that PDHE1alpha1 expression and phosphorylation was altered in rat brain following controlled cortical impact (CCI)-induced TBI. Compared to naïve controls (=100%), PDHE1alpha1 protein decreased significantly ipsilateral to CCI (62%, P<0.05; 75%, P<0.05; 57%, P<0.05; and 39%, P<0.01) and contralateral to CCI (77%, 78%, 78% and 36% P<0.01) at 4h, 24h, 3- and 7-day post-CCI, respectively. PDHE1alpha1 protein phosphorylation level also decreased significantly ipsilateral to CCI (31%, P<0.01; 102%, P>0.05; 64%, P<0.05; and 14%, P<0.01) and to contralateral CCI (35%, 74%, P<0.05; 60%, P<0.05; 20%, P<0.01) at 4h, 24h, 3- and 7-day post-CCI, respectively. Similar reduction in PDHE1alpha1 and p-PDHE1alpha1 protein was found in the craniotomy (sham CCI) group. TBI-induced change in PDHE1alpha1 expression and phosphorylation could alter brain PDH activity and glucose metabolism.
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Affiliation(s)
- Guoqiang Xing
- Department of Psychiatry, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814-4799, United States.
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Hutchinson PJ, O'Connell MT, Seal A, Nortje J, Timofeev I, Al-Rawi PG, Coles JP, Fryer TD, Menon DK, Pickard JD, Carpenter KLH. A combined microdialysis and FDG-PET study of glucose metabolism in head injury. Acta Neurochir (Wien) 2009; 151:51-61; discussion 61. [PMID: 19099177 DOI: 10.1007/s00701-008-0169-1] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2008] [Accepted: 10/14/2008] [Indexed: 11/27/2022]
Abstract
BACKGROUND Microdialysis continuously monitors the chemistry of a small focal volume of the cerebral extracellular space. Positron emission tomography (PET) establishes metabolism of the whole brain but only for the scan's duration. This study's objective was to apply these techniques together, in patients with traumatic brain injury, to assess the relationship between microdialysis (extracellular glucose, lactate, pyruvate, and the lactate/pyruvate (L/P) ratio as a marker of anaerobic metabolism) and PET parameters of glucose metabolism using the glucose analogue [(18)F]-fluorodeoxyglucose (FDG). In particular, we aimed to determine the fate of glucose in terms of differential metabolism to pyruvate and lactate. MATERIALS AND METHODS Microdialysis catheters (CMA70 or CMA71) were inserted into the cerebral cortex of 17 patients with major head injury. Microdialysis was performed during FDG-PET scans with regions of interest for PET analysis defined by the location of the gold-tipped microdialysis catheter. Microdialysate analysis was performed on a CMA600 analyser. FINDINGS There was significant linear relationship between the PET-derived parameter of glucose metabolism (regional cerebral metabolic rate of glucose; CMRglc) and levels of lactate (r = 0.778, p < 0.0001) and pyruvate (r = 0.799, p < 0.0001), but not with the L/P ratio. CONCLUSION The results suggest that in this population of patients, glucose was metabolised to both lactate and pyruvate, but was not associated with an increase in the L/P ratio. This suggests an increase in glucose metabolism to both lactate and pyruvate, as opposed to a shift towards anaerobic metabolism.
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Affiliation(s)
- Peter J Hutchinson
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, UK.
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Holbein M, Béchir M, Ludwig S, Sommerfeld J, Cottini SR, Keel M, Stocker R, Stover JF. Differential influence of arterial blood glucose on cerebral metabolism following severe traumatic brain injury. Crit Care 2009; 13:R13. [PMID: 19196488 PMCID: PMC2688130 DOI: 10.1186/cc7711] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 12/01/2008] [Accepted: 02/06/2009] [Indexed: 01/04/2023] Open
Abstract
INTRODUCTION Maintaining arterial blood glucose within tight limits is beneficial in critically ill patients. Upper and lower limits of detrimental blood glucose levels must be determined. METHODS In 69 patients with severe traumatic brain injury (TBI), cerebral metabolism was monitored by assessing changes in arterial and jugular venous blood at normocarbia (partial arterial pressure of carbon dioxide (paCO2) 4.4 to 5.6 kPa), normoxia (partial arterial pressure of oxygen (paO2) 9 to 20 kPa), stable haematocrit (27 to 36%), brain temperature 35 to 38 degrees C, and cerebral perfusion pressure (CPP) 70 to 90 mmHg. This resulted in a total of 43,896 values for glucose uptake, lactate release, oxygen extraction ratio (OER), carbon dioxide (CO2) and bicarbonate (HCO3) production, jugular venous oxygen saturation (SjvO2), oxygen-glucose index (OGI), lactate-glucose index (LGI) and lactate-oxygen index (LOI). Arterial blood glucose concentration-dependent influence was determined retrospectively by assessing changes in these parameters within pre-defined blood glucose clusters, ranging from less than 4 to more than 9 mmol/l. RESULTS Arterial blood glucose significantly influenced signs of cerebral metabolism reflected by increased cerebral glucose uptake, decreased cerebral lactate production, reduced oxygen consumption, negative LGI and decreased cerebral CO2/HCO3 production at arterial blood glucose levels above 6 to 7 mmol/l compared with lower arterial blood glucose concentrations. At blood glucose levels more than 8 mmol/l signs of increased anaerobic glycolysis (OGI less than 6) supervened. CONCLUSIONS Maintaining arterial blood glucose levels between 6 and 8 mmol/l appears superior compared with lower and higher blood glucose concentrations in terms of stabilised cerebral metabolism. It appears that arterial blood glucose values below 6 and above 8 mmol/l should be avoided. Prospective analysis is required to determine the optimal arterial blood glucose target in patients suffering from severe TBI.
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Affiliation(s)
- Monika Holbein
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, Zuerich, 8091, Switzerland
| | - Markus Béchir
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, Zuerich, 8091, Switzerland
| | - Silke Ludwig
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, Zuerich, 8091, Switzerland
| | - Jutta Sommerfeld
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, Zuerich, 8091, Switzerland
| | - Silvia R Cottini
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, Zuerich, 8091, Switzerland
| | - Marius Keel
- Department of Surgery, Division of Trauma Surgery, University Hospital Zuerich, Raemistrasse 100, Zuerich, 8091, Switzerland
| | - Reto Stocker
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, Zuerich, 8091, Switzerland
| | - John F Stover
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, Zuerich, 8091, Switzerland
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Avila MA, Sell SL, Kadoi Y, Prough DS, Hellmich HL, Velasco M, Dewitt DS. L-Arginine decreases fluid-percussion injury-induced neuronal nitrotyrosine immunoreactivity in rats. J Cereb Blood Flow Metab 2008; 28:1733-41. [PMID: 18612319 DOI: 10.1038/jcbfm.2008.66] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Peroxynitrite is a powerful oxidant capable of nitrating phenolic moieties, such as tyrosine or tyrosine residues in proteins and increases after traumatic brain injury (TBI). First, we tested the hypothesis that TBI increases nitrotyrosine (NT) immunoreactivity in the brain by measuring the number of NT-immunoreactive neurons in the cerebral cortex and hippocampus of rats subjected to parasagittal fluid-percussion TBI. Second, we tested the hypothesis that treatment with L-arginine, a substrate for nitric oxide synthase, further increases NT immunoreactivity over TBI alone. Rats were anesthetized with isoflurane and subjected to TBI, sham TBI, or TBI followed by treatment with L-arginine (100 mg/kg). Twelve, 24, or 72 h after TBI, brains were harvested. Coronal sections (10 microm) were incubated overnight with rabbit polyclonal anti-NT antibody, rinsed, and incubated with a biotinylated secondary antibody. The antigen-antibody complex was visualized using a peroxidase-conjugated system with diaminobenzidine as the chromagen. The number of NT-positive cortical and hippocampal neurons increased significantly in both ipsilateral and contralateral hemispheres up to 72 h after TBI compared with the sham-injured group. Remarkably, treatment with L-arginine reduced the number of NT-positive neurons after TBI in both cortex and hippocampus. Our results indicate that L-arginine actually prevents TBI-induced increases in NT immunoreactivity.
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Affiliation(s)
- Marcela A Avila
- Charles R. Allen Research Laboratories, Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas 77555-0830, USA
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Jamshidi N, Palsson BØ. Top-down analysis of temporal hierarchy in biochemical reaction networks. PLoS Comput Biol 2008; 4:e1000177. [PMID: 18787685 PMCID: PMC2518853 DOI: 10.1371/journal.pcbi.1000177] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2007] [Accepted: 08/04/2008] [Indexed: 11/19/2022] Open
Abstract
The study of dynamic functions of large-scale biological networks has intensified in recent years. A critical component in developing an understanding of such dynamics involves the study of their hierarchical organization. We investigate the temporal hierarchy in biochemical reaction networks focusing on: (1) the elucidation of the existence of “pools” (i.e., aggregate variables) formed from component concentrations and (2) the determination of their composition and interactions over different time scales. To date the identification of such pools without prior knowledge of their composition has been a challenge. A new approach is developed for the algorithmic identification of pool formation using correlations between elements of the modal matrix that correspond to a pair of concentrations and how such correlations form over the hierarchy of time scales. The analysis elucidates a temporal hierarchy of events that range from chemical equilibration events to the formation of physiologically meaningful pools, culminating in a network-scale (dynamic) structure–(physiological) function relationship. This method is validated on a model of human red blood cell metabolism and further applied to kinetic models of yeast glycolysis and human folate metabolism, enabling the simplification of these models. The understanding of temporal hierarchy and the formation of dynamic aggregates on different time scales is foundational to the study of network dynamics and has relevance in multiple areas ranging from bacterial strain design and metabolic engineering to the understanding of disease processes in humans. Cellular metabolism describes the complex web of biochemical transformations that are necessary to build the structural components, to convert nutrients into “usable energy” by the cell, and to degrade or excrete the by-products. A critical aspect toward understanding metabolism is the set of dynamic interactions between metabolites, some of which occur very quickly while others occur more slowly. To develop a “systems” understanding of how networks operate dynamically we need to identify the different processes that occur on different time scales. When one moves from very fast time scales to slower ones, certain components in the network move in concert and pool together. We develop a method to elucidate the time scale hierarchy of a network and to simplify its structure by identifying these pools. This is applied to dynamic models of metabolism for the human red blood cell, human folate metabolism, and yeast glycolysis. It was possible to simplify the structure of these networks into biologically meaningful groups of variables. Because dynamics play important roles in normal and abnormal function in biology, it is expected that this work will contribute to an area of great relevance for human disease and engineering applications.
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Affiliation(s)
- Neema Jamshidi
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Bernhard Ø. Palsson
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
- * E-mail:
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Davis LM, Pauly JR, Readnower RD, Rho JM, Sullivan PG. Fasting is neuroprotective following traumatic brain injury. J Neurosci Res 2008; 86:1812-22. [DOI: 10.1002/jnr.21628] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Meier R, Béchir M, Ludwig S, Sommerfeld J, Keel M, Steiger P, Stocker R, Stover JF. Differential temporal profile of lowered blood glucose levels (3.5 to 6.5 mmol/l versus 5 to 8 mmol/l) in patients with severe traumatic brain injury. Crit Care 2008; 12:R98. [PMID: 18680584 PMCID: PMC2575586 DOI: 10.1186/cc6974] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Revised: 07/14/2008] [Accepted: 08/04/2008] [Indexed: 01/04/2023] Open
Abstract
INTRODUCTION Hyperglycaemia is detrimental, but maintaining low blood glucose levels within tight limits is controversial in patients with severe traumatic brain injury, because decreased blood glucose levels can induce and aggravate underlying brain injury. METHODS In 228 propensity matched patients (age, sex and injury severity) treated in our intensive care unit (ICU) from 2000 to 2004, we retrospectively evaluated the influence of different predefined blood glucose targets (3.5 to 6.5 versus 5 to 8 mmol/l) on frequency of hypoglycaemic and hyperglycaemic episodes, insulin and norepinephrine requirement, changes in intracranial pressure and cerebral perfusion pressure, mortality and length of stay on the ICU. RESULTS Mortality and length of ICU stay were similar in both blood glucose target groups. Blood glucose values below and above the predefined levels were significantly increased in the 3.5 to 6.5 mmol/l group, predominantly during the first week. Insulin and norepinephrine requirements were markedly increased in this group. During the second week, the incidences of intracranial pressure exceeding 20 mmHg and infectious complications were significantly decreased in the 3.5 to 6.5 mmol/l group. CONCLUSION Maintaining blood glucose within 5 to 8 mmol/l appears to yield greater benefit during the first week. During the second week, 3.5 to 6.5 mmol/l is associated with beneficial effects in terms of reduced intracranial hypertension and decreased rate of pneumonia, bacteraemia and urinary tract infections. It remains to be determined whether patients might profit from temporally adapted blood glucose limits, inducing lower values during the second week, and whether concomitant glucose infusion to prevent hypoglycaemia is safe in patients with post-traumatic oedema.
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Affiliation(s)
- Regula Meier
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, CH 8091 Zuerich, Switzerland
| | - Markus Béchir
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, CH 8091 Zuerich, Switzerland
| | - Silke Ludwig
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, CH 8091 Zuerich, Switzerland
| | - Jutta Sommerfeld
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, CH 8091 Zuerich, Switzerland
| | - Marius Keel
- Department of Surgery, Division of Trauma Surgery, University Hospital Zuerich, Raemistrasse 100, CH 8091 Zuerich, Switzerland
| | - Peter Steiger
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, CH 8091 Zuerich, Switzerland
| | - Reto Stocker
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, CH 8091 Zuerich, Switzerland
| | - John F Stover
- Surgical Intensive Care Medicine, University Hospital Zuerich, Raemistrasse 100, CH 8091 Zuerich, Switzerland
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Jiang X, Li J, Ma L. Metabolic enzymes link morphine withdrawal with metabolic disorder. Cell Res 2007; 17:741-3. [PMID: 17851588 DOI: 10.1038/cr.2007.75] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Xi Jiang
- National Laboratory of Medical Neurobiology and Pharmacology Research Center, Shanghai Medical College and Institutes of Brain Science, Fudan University, Shanghai, China
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