1
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Orr TJ, Lesha E, Kramer AH, Cecia A, Dugan JE, Schwartz B, Einhaus SL. Traumatic Brain Injury: A Comprehensive Review of Biomechanics and Molecular Pathophysiology. World Neurosurg 2024; 185:74-88. [PMID: 38272305 DOI: 10.1016/j.wneu.2024.01.084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 01/14/2024] [Accepted: 01/16/2024] [Indexed: 01/27/2024]
Abstract
Traumatic brain injury (TBI) is a critical public health concern with profound consequences for affected individuals. This comprehensive literature review delves into TBI intricacies, encompassing primary injury biomechanics and the molecular pathophysiology of the secondary injury cascade. Primary TBI involves a complex interplay of forces, including impact loading, blast overpressure, and impulsive loading, leading to diverse injury patterns. These forces can be categorized into inertial (e.g., rotational acceleration causing focal and diffuse injuries) and contact forces (primarily causing focal injuries like skull fractures). Understanding their interactions is crucial for effective injury management. The secondary injury cascade in TBI comprises multifaceted molecular and cellular responses, including altered ion concentrations, dysfunctional neurotransmitter networks, oxidative stress, and cellular energy disturbances. These disruptions impair synaptic function, neurotransmission, and neuroplasticity, resulting in cognitive and behavioral deficits. Moreover, neuroinflammatory responses play a pivotal role in exacerbating damage. As we endeavor to bridge the knowledge gap between biomechanics and molecular pathophysiology, further research is imperative to unravel the nuanced interplay between mechanical forces and their consequences at the molecular and cellular levels, ultimately guiding the development of targeted therapeutic strategies to mitigate the debilitating effects of TBI. In this study, we aim to provide a concise review of the bridge between biomechanical processes causing primary injury and the ensuing molecular pathophysiology of secondary injury, while detailing the subsequent clinical course for this patient population. This knowledge is crucial for advancing our understanding of TBI and developing effective interventions to improve outcomes for those affected.
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Affiliation(s)
- Taylor J Orr
- College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee.
| | - Emal Lesha
- Department of Neurological Surgery, University of Tennessee Health Science Center, Memphis, Tennessee; Semmes Murphey Clinic, Memphis, Tennessee
| | - Alexandra H Kramer
- College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Arba Cecia
- School of Medicine, Loyola University Chicago, Chicago, Illinois
| | - John E Dugan
- College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Barrett Schwartz
- Department of Neurological Surgery, University of Tennessee Health Science Center, Memphis, Tennessee; Semmes Murphey Clinic, Memphis, Tennessee
| | - Stephanie L Einhaus
- Department of Neurological Surgery, University of Tennessee Health Science Center, Memphis, Tennessee; Semmes Murphey Clinic, Memphis, Tennessee
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2
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Zhou T, Zhong Y, Zhang Y, Zhou Y. Pyruvate Dehydrogenase Complex in Neonatal Hypoxic-Ischemic Brain Injury. ACS Pharmacol Transl Sci 2024; 7:42-47. [PMID: 38230287 PMCID: PMC10789137 DOI: 10.1021/acsptsci.3c00191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 12/02/2023] [Accepted: 12/05/2023] [Indexed: 01/18/2024]
Abstract
The disruption of cerebral energy metabolism in relation to brain damage has been the subject of extensive research. However, the pyruvate dehydrogenase complex (PDHC), which is primarily characterized by poor cerebral energy metabolism following brain trauma, has received relatively little study in comparison to newborn hypoxic-ischemic brain injury. Mitochondrial PDHC, a multienzyme complex that functions as a crucial hub in energy metabolism and acts as a central metabolic node to mediate pyruvate oxidation after glycolysis and fuel the Krebs cycle to meet energy demands, has been reported to be one cause of energy metabolism dysfunction according to recent studies. Here we assess the potential mechanisms of neonatal hypoxic-ischemic brain injury-related brain dysfunction mediated by PDHC and further discuss the neuroprotective effects of therapeutic medicines that target PDHC activation. We also provide a summary of recent research on medicines that target PDHC in neonates with hypoxic-ischemic brain damage. Through an understanding of the mechanisms by which it is modulated and an investigation of the neuroprotective techniques available to activate brain PDHC and improve neonatal hypoxic-ischemic impairment, our review emphasizes the significance of PDHC impairment in neonatal hypoxic-ischemic brain injury.
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Affiliation(s)
- Tao Zhou
- Department
of Pharmaceutical and Medical Equipment, Rongtong Bayi Orthopedic Hospital of China, Chengdu 610031, China
| | - Yuangao Zhong
- Department
of Pharmaceutical Preparation Rongtong Bayi Orthopedic Hospital Of
China, Chengdu 610031, China
| | - Yong Zhang
- Department
of Pharmaceutical Preparation Rongtong Bayi Orthopedic Hospital Of
China, Chengdu 610031, China
| | - Yue Zhou
- Department
of Pharmacy, Xindu District People’s
Hospital of Chengdu, Chengdu 610500, China
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3
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Li Y, Wang Z, Li J, Yu Y, Wang Y, Jin X, Dong Y, Liu Q, Duan X, Yan N. Sodium Butyrate Ameliorates Fluorosis-Induced Neurotoxicity by Regulating Hippocampal Glycolysis In Vivo. Biol Trace Elem Res 2023; 201:5230-5241. [PMID: 36710293 DOI: 10.1007/s12011-023-03583-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 01/22/2023] [Indexed: 01/31/2023]
Abstract
Fluorosis can induce neurotoxicity. Sodium butyrate (SB), a histone deacetylase inhibitor, has important research potential in correcting glucose metabolism disorders and is widely used in a variety of neurological diseases and metabolic diseases, but it is not yet known whether it plays a role in combating fluoride-induced neurotoxicity. This study aims to evaluate the effect of SB on fluoride neurotoxicity and the possible associated mechanisms. The results of HE staining and Morris water maze showed that, in mice exposed to 100 mg/L fluoride for 3 months, the hippocampal cells arranged in loosely with large cell gaps and diminished in number. One thousand milligram per kilogram per day SB treatment improved fluoride-induced neuronal cell damage and spatial learning memory impairment. Western blot results showed that the abundance of malate dehydrogenase 2 (MDH2) and pyruvate dehydrogenase (PDH) in the hippocampus of fluorosis mice was increased, the abundance of pyruvate kinase M (PKM), lactate dehydrogenase (LDH), hexokinase (HK), phosphatidylinositol 3-kinase (PI3K), phosphorylated Akt (P-AKT), and hypoxia-inducible factor 1α (HIF-1α) was inhibited, and the content of lactate and ATP was decreased. SB treatment reversed the decreased glycolysis in the hippocampus of fluorosis mice. These results suggested that SB could ameliorate fluorosis-induced neurotoxicity, which might be linked with its function in regulating glycolysis as well as inhibition of the PI3K/AKT/HIF-1α pathway. Sodium butyrate ameliorates fluorosis-induced neurotoxicity by regulating hippocampal glycolysis in vivo (created with MedPeer (www.medpeer.cn)).
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Affiliation(s)
- Yangjie Li
- College of Basic Medicine, Shenyang Medical College, Shenyang, 110034, China
| | - Zhengdong Wang
- College of Basic Medicine, Shenyang Medical College, Shenyang, 110034, China
| | - Jing Li
- School of Pharmacy, Shenyang Medical College, Shenyang, 110034, China
| | - Yang Yu
- School of Medical Applied Technology, Shenyang Medical College, Shenyang, 110034, China
| | - Yuan Wang
- Central Hospital Affiliated to Shenyang Medical College, Shenyang, 110034, China
| | - Xiaoxia Jin
- School of Public Health, Shenyang Medical College, Shenyang, 110034, China
| | - Yun Dong
- Central Hospital Affiliated to Shenyang Medical College, Shenyang, 110034, China
| | - Qingsong Liu
- School of Public Health, Shenyang Medical College, Shenyang, 110034, China
| | - Xiaoxu Duan
- School of Public Health, Shenyang Medical College, Shenyang, 110034, China.
| | - Nan Yan
- School of Medical Applied Technology, Shenyang Medical College, Shenyang, 110034, China.
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4
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Kong LZ, Zhang RL, Hu SH, Lai JB. Military traumatic brain injury: a challenge straddling neurology and psychiatry. Mil Med Res 2022; 9:2. [PMID: 34991734 PMCID: PMC8740337 DOI: 10.1186/s40779-021-00363-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Accepted: 12/27/2021] [Indexed: 12/12/2022] Open
Abstract
Military psychiatry, a new subcategory of psychiatry, has become an invaluable, intangible effect of the war. In this review, we begin by examining related military research, summarizing the related epidemiological data, neuropathology, and the research achievements of diagnosis and treatment technology, and discussing its comorbidity and sequelae. To date, advances in neuroimaging and molecular biology have greatly boosted the studies on military traumatic brain injury (TBI). In particular, in terms of pathophysiological mechanisms, several preclinical studies have identified abnormal protein accumulation, blood-brain barrier damage, and brain metabolism abnormalities involved in the development of TBI. As an important concept in the field of psychiatry, TBI is based on organic injury, which is largely different from many other mental disorders. Therefore, military TBI is both neuropathic and psychopathic, and is an emerging challenge at the intersection of neurology and psychiatry.
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Affiliation(s)
- Ling-Zhuo Kong
- Department of Psychiatry, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Rui-Li Zhang
- Department of Psychiatry, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Shao-Hua Hu
- Department of Psychiatry, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China. .,The Key Laboratory of Mental Disorder's Management in Zhejiang Province, Hangzhou, 310003, China. .,Brain Research Institute of Zhejiang University, Hangzhou, 310003, China. .,Zhejiang Engineering Center for Mathematical Mental Health, Hangzhou, 310003, China. .,MOE Frontier Science Center for Brain Science and Brain-Machine Integration, Zhejiang University, Hangzhou, 310003, China.
| | - Jian-Bo Lai
- Department of Psychiatry, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China. .,The Key Laboratory of Mental Disorder's Management in Zhejiang Province, Hangzhou, 310003, China. .,Brain Research Institute of Zhejiang University, Hangzhou, 310003, China. .,Zhejiang Engineering Center for Mathematical Mental Health, Hangzhou, 310003, China. .,MOE Frontier Science Center for Brain Science and Brain-Machine Integration, Zhejiang University, Hangzhou, 310003, China.
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5
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Sowers JL, Sowers ML, Shavkunov AS, Hawkins BE, Wu P, DeWitt DS, Prough DS, Zhang K. Traumatic brain injury induces region-specific glutamate metabolism changes as measured by multiple mass spectrometry methods. iScience 2021; 24:103108. [PMID: 34622161 PMCID: PMC8479783 DOI: 10.1016/j.isci.2021.103108] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 06/14/2021] [Accepted: 09/08/2021] [Indexed: 11/02/2022] Open
Abstract
The release of excess glutamate following traumatic brain injury (TBI) results in glutamate excitotoxicity and metabolic energy failure. Endogenous mechanisms for reducing glutamate concentration in the brain parenchyma following TBI are poorly understood. Using multiple mass spectrometry approaches, we examined TBI-induced changes to glutamate metabolism. We present evidence that glutamate concentration can be reduced by glutamate oxidation via a "truncated" tricarboxylic acid cycle coupled to the urea cycle. This process reduces glutamate levels, generates carbon for energy metabolism, leads to citrulline accumulation, and produces nitric oxide. Several key metabolites are identified by metabolomics in support of this mechanism and the locations of these metabolites in the injured hemisphere are demonstrated by MALDI-MS imaging. The results of this study establish the advantages of multiple mass spectrometry approaches and provide insights into glutamate metabolism following TBI that could lead to improved treatment approaches.
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Affiliation(s)
- James L Sowers
- MD-PhD Combined Degree Program, University of Texas Medical Branch, Galveston, TX 77555, USA.,Department of Neuroscience, Cell Biology, and Anatomy, University of Texas Medical Branch, Galveston, TX 77555, USA.,The Moody Project for Translational Traumatic Brain Injury Research, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Mark L Sowers
- MD-PhD Combined Degree Program, University of Texas Medical Branch, Galveston, TX 77555, USA.,Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Alexander S Shavkunov
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Bridget E Hawkins
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX 77555, USA.,The Moody Project for Translational Traumatic Brain Injury Research, University of Texas Medical Branch, Galveston, TX 77555, USA.,Research Innovation and Scientific Excellence (RISE) Center, School of Nursing, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Ping Wu
- Department of Neuroscience, Cell Biology, and Anatomy, University of Texas Medical Branch, Galveston, TX 77555, USA.,The Moody Project for Translational Traumatic Brain Injury Research, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Douglas S DeWitt
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX 77555, USA.,The Moody Project for Translational Traumatic Brain Injury Research, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Donald S Prough
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX 77555, USA.,The Moody Project for Translational Traumatic Brain Injury Research, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Kangling Zhang
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, USA.,The Moody Project for Translational Traumatic Brain Injury Research, University of Texas Medical Branch, Galveston, TX 77555, USA
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6
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Solano Fonseca R, Metang P, Egge N, Liu Y, Zuurbier KR, Sivaprakasam K, Shirazi S, Chuah A, Arneaud SL, Konopka G, Qian D, Douglas PM. Glycolytic preconditioning in astrocytes mitigates trauma-induced neurodegeneration. eLife 2021; 10:69438. [PMID: 34473622 PMCID: PMC8448530 DOI: 10.7554/elife.69438] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 08/24/2021] [Indexed: 01/02/2023] Open
Abstract
Concussion is associated with a myriad of deleterious immediate and long-term consequences. Yet the molecular mechanisms and genetic targets promoting the selective vulnerability of different neural subtypes to dysfunction and degeneration remain unclear. Translating experimental models of blunt force trauma in C. elegans to concussion in mice, we identify a conserved neuroprotective mechanism in which reduction of mitochondrial electron flux through complex IV suppresses trauma-induced degeneration of the highly vulnerable dopaminergic neurons. Reducing cytochrome C oxidase function elevates mitochondrial-derived reactive oxygen species, which signal through the cytosolic hypoxia inducing transcription factor, Hif1a, to promote hyperphosphorylation and inactivation of the pyruvate dehydrogenase, PDHE1α. This critical enzyme initiates the Warburg shunt, which drives energetic reallocation from mitochondrial respiration to astrocyte-mediated glycolysis in a neuroprotective manner. These studies demonstrate a conserved process in which glycolytic preconditioning suppresses Parkinson-like hypersensitivity of dopaminergic neurons to trauma-induced degeneration via redox signaling and the Warburg effect. Concussion is a type of traumatic brain injury that results from a sudden blow or jolt to the head. Symptoms can include a passing headache, dizziness, confusion or sensitivity to light, but experiencing multiple concussions can have drastic repercussions in later life. Studies of professional athletes have shown that those who experience one or more concussions are prone to developing Alzheimer’s and Parkinson’s disease, two well-known neurodegenerative diseases. Both conditions involve the progressive loss or breakdown of nerve cells, called neurons. But exactly how this so-called neurodegeneration of brain cells stems from the original, physical injury remains unclear. Head trauma may cause damage to the structural support of a cell or disrupt the flow of electrical impulses through neurons. Energy use and production in damaged cells could shift into overdrive to repair the damage. The chemical properties of different types of brain cells could also make some more vulnerable to trauma than others. Besides neurons, star-shaped support cells in the brain called astrocytes, which may have some protective ability, could also be affected. To investigate which cells may be more susceptible to traumatic injuries, Solano Fonseca et al. modelled the impacts of concussion-like head trauma in roundworms (C. elegans) and mice. In both animals, one type of neuron was extremely vulnerable to cell death after trauma. Neurons that release dopamine, a chemical involved in cell-to-cell communication and the brain’s reward system, showed signs of cell damage and deteriorated after injury. Dopaminergic cells, as these cells are called, are involved in motor coordination, and the loss of dopaminergic cells has been linked to both Alzheimer’s and Parkinson’s disease. Astrocytes, however, had a role in reducing the death of dopaminergic neurons after trauma. In experiments, astrocytes appeared to restore the balance of energy production to meet the increased energy demands of impacted neurons. Single-cell analyses showed that genes involved in metabolism were switched on in astrocytes to produce energy via an alternative pathway. This energetic shift facilitated via astrocytes may help mitigate against some damage to dopamine-producing neurons after trauma, reducing cell death. This work furthers our understanding of cellular changes in the concussed brain. More research will be required to better characterise how this immediate trauma to cells, and the subsequent loss of dopaminergic neurons, impacts brain health long-term. Efforts to design effective therapies to slow or reverse these changes could then follow.
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Affiliation(s)
- Rene Solano Fonseca
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Patrick Metang
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Nathan Egge
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Yingjian Liu
- Department of Mechanical Engineering, University of Texas at Dallas, Dallas, United States
| | - Kielen R Zuurbier
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States.,O'Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, United States
| | - Karthigayini Sivaprakasam
- O'Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, United States.,Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
| | - Shawn Shirazi
- Department of Integrative Biology, University of California, Berkeley, Berkeley, United States
| | - Ashleigh Chuah
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Sonja Lb Arneaud
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Genevieve Konopka
- O'Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, United States.,Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, United States
| | - Dong Qian
- Department of Mechanical Engineering, University of Texas at Dallas, Dallas, United States
| | - Peter M Douglas
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States.,Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, United States
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7
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Ariyannur PS, Xing G, Barry ES, Benford B, Grunberg NE, Sharma P. Effects of Pyruvate Administration on Mitochondrial Enzymes, Neurological Behaviors, and Neurodegeneration after Traumatic Brain Injury. Aging Dis 2021; 12:983-999. [PMID: 34221543 PMCID: PMC8219499 DOI: 10.14336/ad.2020.1015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 10/15/2020] [Indexed: 01/17/2023] Open
Abstract
Traumatic brain injury (TBI) is known to increase the susceptibility to various age-related neurodegenerative disorders such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). Although the role of damaged mitochondrial electron transport chain (ETC) in the progression of AD and PD has been identified, its relationship with altered expression of neurodegenerative proteins has not been examined before. This study aimed to investigate 1) how TBI could affect mitochondrial ETC and neurodegeneration in rat brain regions related to behavioral alteration, and 2) if administration of the key mitochondrial substrate pyruvate can improve the outcome of mild TBI (mTBI). In a rat lateral fluid percussion injury model of mTBI, sodium pyruvate in sterile distilled water (1 g/kg body weight) was administered orally daily for 7 days. The protein expression of mitochondrial ETC enzymes, and neurodegeneration proteins in the hippocampus and cerebral cortex and was assessed on Day 7. The hippocampal and cortical expressions of ETC complex I, III, IV, V were significantly and variably impaired following mTBI. Pyruvate treatment altered ETC complex expression, reduced the nitrosyl stress and the MBP expression in the injured brain area, but increased the expression of the glial fibrillary acidic protein (GFAP) and Tau proteins. Pyruvate after mTBI augmented the Rotarod performance but decreased the horizontal and vertical open field locomotion activities and worsened neurobehavioural severity score, indicating a debilitating therapeutic effect on the acute phase of mTBI. These results suggest bidirectional neuroprotective and neurodegenerative modulating effects of pyruvate on TBI-induced alteration in mitochondrial activity and motor behavior. Pyruvate could potentially stimulate the proliferation of astrogliosis, and lactate acidosis, and caution should be exercised when used as a therapy in the acute phase of mTBI. More effective interventions targeted at multiple mechanisms are needed for the prevention and treatment of TBI-induced long-term neurodegeneration.
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Affiliation(s)
- Prasanth S Ariyannur
- 1Department of Anesthesiology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.,3Department of Biochemistry & Molecular Biology, Amrita Institute of Medical Sciences, Amrita Vishwa Vidyapeetham, Kochi 682041, India
| | - Guoqiang Xing
- 1Department of Anesthesiology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.,2Imaging Institute of Rehabilitation and Development of Brain Function, the Affiliated Hospital and the Second Clinical Medical College of North Sichuan Medical University, Nanchong Central Hospital, Nanchong 637000, China
| | - Erin S Barry
- 4Military & Emergency Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Brandi Benford
- 1Department of Anesthesiology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Neil E Grunberg
- 4Military & Emergency Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Pushpa Sharma
- 1Department of Anesthesiology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
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8
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DeVience SJ, Lu X, Proctor JL, Rangghran P, Medina JA, Melhem ER, Gullapalli RP, Fiskum G, Mayer D. Enhancing Metabolic Imaging of Energy Metabolism in Traumatic Brain Injury Using Hyperpolarized [1- 13C]Pyruvate and Dichloroacetate. Metabolites 2021; 11:metabo11060335. [PMID: 34073714 PMCID: PMC8225170 DOI: 10.3390/metabo11060335] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/15/2021] [Accepted: 05/16/2021] [Indexed: 11/29/2022] Open
Abstract
Hyperpolarized magnetic resonance spectroscopic imaging (MRSI) of [1-13C]pyruvate metabolism has previously been used to assess the effects of traumatic brain injury (TBI) in rats. Here, we show that MRSI can be used in conjunction with dichloroacetate to measure the phosphorylation state of pyruvate dehydrogenase (PDH) following mild-to-moderate TBI, and that measurements can be repeated in a longitudinal study to monitor the course of injury progression and recovery. We found that the level of 13C-bicarbonate and the bicarbonate-to-lactate ratio decreased on the injured side of the brain four hours after injury and continued to decrease through day 7. Levels recovered to normal by day 28. Measurements following dichloroacetate administration showed that PDH was inhibited equally by PDH kinase (PDK) on both sides of the brain. Therefore, the decrease in aerobic metabolism is not due to inhibition by PDK.
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Affiliation(s)
- Stephen J. DeVience
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (S.J.D.); (X.L.); (E.R.M.); (R.P.G.)
- Center for Metabolic Imaging & Therapeutics (CMIT), University of Maryland Medical Center, Baltimore, MD 21201, USA
| | - Xin Lu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (S.J.D.); (X.L.); (E.R.M.); (R.P.G.)
- Center for Metabolic Imaging & Therapeutics (CMIT), University of Maryland Medical Center, Baltimore, MD 21201, USA
| | - Julie L. Proctor
- Department of Anesthesiology and the Center for Shock, Trauma, and Anesthesiology Research (S.T.A.R.), University of Maryland School of Medicine, Baltimore, MD 21201, USA; (J.L.P.); (P.R.); (J.A.M.); (G.F.)
| | - Parisa Rangghran
- Department of Anesthesiology and the Center for Shock, Trauma, and Anesthesiology Research (S.T.A.R.), University of Maryland School of Medicine, Baltimore, MD 21201, USA; (J.L.P.); (P.R.); (J.A.M.); (G.F.)
| | - Juliana A. Medina
- Department of Anesthesiology and the Center for Shock, Trauma, and Anesthesiology Research (S.T.A.R.), University of Maryland School of Medicine, Baltimore, MD 21201, USA; (J.L.P.); (P.R.); (J.A.M.); (G.F.)
| | - Elias R. Melhem
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (S.J.D.); (X.L.); (E.R.M.); (R.P.G.)
- Center for Metabolic Imaging & Therapeutics (CMIT), University of Maryland Medical Center, Baltimore, MD 21201, USA
| | - Rao P. Gullapalli
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (S.J.D.); (X.L.); (E.R.M.); (R.P.G.)
- Center for Metabolic Imaging & Therapeutics (CMIT), University of Maryland Medical Center, Baltimore, MD 21201, USA
| | - Gary Fiskum
- Department of Anesthesiology and the Center for Shock, Trauma, and Anesthesiology Research (S.T.A.R.), University of Maryland School of Medicine, Baltimore, MD 21201, USA; (J.L.P.); (P.R.); (J.A.M.); (G.F.)
| | - Dirk Mayer
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (S.J.D.); (X.L.); (E.R.M.); (R.P.G.)
- Center for Metabolic Imaging & Therapeutics (CMIT), University of Maryland Medical Center, Baltimore, MD 21201, USA
- Correspondence:
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9
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Underwood E, Redell JB, Zhao J, Moore AN, Dash PK. A method for assessing tissue respiration in anatomically defined brain regions. Sci Rep 2020; 10:13179. [PMID: 32764697 PMCID: PMC7413397 DOI: 10.1038/s41598-020-69867-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 07/16/2020] [Indexed: 12/28/2022] Open
Abstract
The survival and function of brain cells requires uninterrupted ATP synthesis. Different brain structures subserve distinct neurological functions, and therefore have different energy production/consumption requirements. Typically, mitochondrial function is assessed following their isolation from relatively large amounts of starting tissue, making it difficult to ascertain energy production/failure in small anatomical locations. In order to overcome this limitation, we have developed and optimized a method to measure mitochondrial function in brain tissue biopsy punches excised from anatomically defined brain structures, including white matter tracts. We describe the procedures for maintaining tissue viability prior to performing the biopsy punches, as well as provide guidance for optimizing punch size and the drug doses needed to assess various aspects of mitochondrial respiration. We demonstrate that our method can be used to measure mitochondrial respiration in anatomically defined subfields within the rat hippocampus. Using this method, we present experimental results which show that a mild traumatic brain injury (mTBI, often referred to as concussion) causes differential mitochondrial responses within these hippocampal subfields and the corpus callosum, novel findings that would have been difficult to obtain using traditional mitochondrial isolation methods. Our method is easy to implement and will be of interest to researchers working in the field of brain bioenergetics and brain diseases.
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Affiliation(s)
- Erica Underwood
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - John B Redell
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Jing Zhao
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Anthony N Moore
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, Houston, TX, 77030, USA
| | - Pramod K Dash
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, Houston, TX, 77030, USA.
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10
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Pyruvate Dehydrogenase and Tricarboxylic Acid Cycle Enzymes Are Sensitive Targets of Traumatic Brain Injury Induced Metabolic Derangement. Int J Mol Sci 2019; 20:ijms20225774. [PMID: 31744143 PMCID: PMC6888669 DOI: 10.3390/ijms20225774] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 11/05/2019] [Accepted: 11/13/2019] [Indexed: 02/06/2023] Open
Abstract
Using a closed-head impact acceleration model of mild or severe traumatic brain injury (mTBI or sTBI, respectively) in rats, we evaluated the effects of graded head impacts on the gene and protein expressions of pyruvate dehydrogenase (PDH), as well as major enzymes of mitochondrial tricarboxylic acid cycle (TCA). TBI was induced in anaesthetized rats by dropping 450 g from 1 (mTBI) or 2 m height (sTBI). After 6 h, 12 h, 24 h, 48 h, and 120 h gene expressions of enzymes and subunits of PDH. PDH kinases and phosphatases (PDK1-4 and PDP1-2, respectively), citrate synthase (CS), isocitrate dehydrogenase (IDH), oxoglutarate dehydrogenase (OGDH), succinate dehydrogenase (SDH), succinyl-CoA synthase (SUCLG), and malate dehydrogenase (MDH) were determined in whole brain extracts (n = 6 rats at each time for both TBI levels). In the same samples, the high performance liquid chromatographic (HPLC) determination of acetyl-coenzyme A (acetyl-CoA) and free coenzyme A (CoA-SH) was performed. Sham-operated animals (n = 6) were used as controls. After mTBI, the results indicated a general transient decrease, followed by significant increases, in PDH and TCA gene expressions. Conversely, permanent PDH and TCA downregulation occurred following sTBI. The inhibitory conditions of PDH (caused by PDP1-2 downregulations and PDK1-4 overexpression) and SDH appeared to operate only after sTBI. This produced almost no change in acetyl-CoA and free CoA-SH following mTBI and a remarkable depletion of both compounds after sTBI. These results again demonstrated temporary or steady mitochondrial malfunctioning, causing minimal or profound modifications to energy-related metabolites, following mTBI or sTBI, respectively. Additionally, PDH and SDH appeared to be highly sensitive to traumatic insults and are deeply involved in mitochondrial-related energy metabolism imbalance.
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11
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Bordone MP, Salman MM, Titus HE, Amini E, Andersen JV, Chakraborti B, Diuba AV, Dubouskaya TG, Ehrke E, Espindola de Freitas A, Braga de Freitas G, Gonçalves RA, Gupta D, Gupta R, Ha SR, Hemming IA, Jaggar M, Jakobsen E, Kumari P, Lakkappa N, Marsh APL, Mitlöhner J, Ogawa Y, Paidi RK, Ribeiro FC, Salamian A, Saleem S, Sharma S, Silva JM, Singh S, Sulakhiya K, Tefera TW, Vafadari B, Yadav A, Yamazaki R, Seidenbecher CI. The energetic brain - A review from students to students. J Neurochem 2019; 151:139-165. [PMID: 31318452 DOI: 10.1111/jnc.14829] [Citation(s) in RCA: 130] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 07/03/2019] [Accepted: 07/08/2019] [Indexed: 12/12/2022]
Abstract
The past 20 years have resulted in unprecedented progress in understanding brain energy metabolism and its role in health and disease. In this review, which was initiated at the 14th International Society for Neurochemistry Advanced School, we address the basic concepts of brain energy metabolism and approach the question of why the brain has high energy expenditure. Our review illustrates that the vertebrate brain has a high need for energy because of the high number of neurons and the need to maintain a delicate interplay between energy metabolism, neurotransmission, and plasticity. Disturbances to the energetic balance, to mitochondria quality control or to glia-neuron metabolic interaction may lead to brain circuit malfunction or even severe disorders of the CNS. We cover neuronal energy consumption in neural transmission and basic ('housekeeping') cellular processes. Additionally, we describe the most common (glucose) and alternative sources of energy namely glutamate, lactate, ketone bodies, and medium chain fatty acids. We discuss the multifaceted role of non-neuronal cells in the transport of energy substrates from circulation (pericytes and astrocytes) and in the supply (astrocytes and microglia) and usage of different energy fuels. Finally, we address pathological consequences of disrupted energy homeostasis in the CNS.
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Affiliation(s)
- Melina Paula Bordone
- Facultad de Farmacia y Bioquímica, Instituto de Investigaciones Farmacológicas (ININFA), Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mootaz M Salman
- Department of Cell Biology, Harvard Medical School, and Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Haley E Titus
- Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Elham Amini
- Department of Medicine, University Kebangsaan Malaysia Medical Centre (HUKM), Cheras, Kuala Lumpur, Malaysia
| | - Jens V Andersen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Artem V Diuba
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Tatsiana G Dubouskaya
- Institute of Biophysics and Cell Engineering, National Academy of Sciences of Belarus, Minsk, Belarus
| | - Eric Ehrke
- Centre for Biomolecular Interactions, University of Bremen, Bremen, Germany
| | - Andiara Espindola de Freitas
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, California, USA
| | | | | | | | - Richa Gupta
- CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Sharon R Ha
- Baylor College of Medicine, Houston, Texas, USA
| | - Isabel A Hemming
- Brain Growth and Disease Laboratory, The Harry Perkins Institute of Medical Research, Nedlands, Western Australia, Australia.,School of Medicine and Pharmacology, The University of Western Australia, Crawley, Australia
| | - Minal Jaggar
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Emil Jakobsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Punita Kumari
- Defense Institute of Physiology and allied sciences, Defense Research and Development Organization, Timarpur, Delhi, India
| | - Navya Lakkappa
- Department of Pharmacology, JSS college of Pharmacy, Ooty, India
| | - Ashley P L Marsh
- Bruce Lefroy Centre for Genetic Health Research, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Jessica Mitlöhner
- Department of Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology Magdeburg, Magdeburg, Germany
| | - Yuki Ogawa
- The Jikei University School of Medicine, Minato-ku, Tokyo, Japan
| | | | | | - Ahmad Salamian
- Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Suraiya Saleem
- CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Sorabh Sharma
- Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan, India
| | - Joana M Silva
- Life and Health Sciences Research Institute (ICVS), Medical School, University of Minho, Braga, Portugal
| | - Shripriya Singh
- CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Kunjbihari Sulakhiya
- Department of Pharmacy, Indira Gandhi National Tribal University, Amarkantak, India
| | - Tesfaye Wolde Tefera
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Behnam Vafadari
- Institute of environmental medicine, UNIKA-T, Technical University of Munich, Munich, Germany
| | - Anuradha Yadav
- CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Reiji Yamazaki
- Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan.,Center for Behavioral Brain Sciences (CBBS), Otto von Guericke University, Magdeburg, Germany
| | - Constanze I Seidenbecher
- Department of Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology Magdeburg, Magdeburg, Germany.,Center for Behavioral Brain Sciences (CBBS), Otto von Guericke University, Magdeburg, Germany
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12
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The Effects of Sodium Dichloroacetate on Mitochondrial Dysfunction and Neuronal Death Following Hypoglycemia-Induced Injury. Cells 2019; 8:cells8050405. [PMID: 31052436 PMCID: PMC6562710 DOI: 10.3390/cells8050405] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/17/2019] [Accepted: 05/01/2019] [Indexed: 12/15/2022] Open
Abstract
Our previous studies demonstrated that some degree of neuronal death is caused by hypoglycemia, but a subsequent and more severe wave of neuronal cell death occurs due to glucose reperfusion, which results from the rapid restoration of low blood glucose levels. Mitochondrial dysfunction caused by hypoglycemia leads to increased levels of pyruvate dehydrogenase kinase (PDK) and suppresses the formation of ATP by inhibiting pyruvate dehydrogenase (PDH) activation, which can convert pyruvate into acetyl-coenzyme A (acetyl-CoA). Sodium dichloroacetate (DCA) is a PDK inhibitor and activates PDH, the gatekeeper of glucose oxidation. However, no studies about the effect of DCA on hypoglycemia have been published. In the present study, we hypothesized that DCA treatment could reduce neuronal death through improvement of glycolysis and prevention of reactive oxygen species production after hypoglycemia. To test this, we used an animal model of insulin-induced hypoglycemia and injected DCA (100 mg/kg, i.v., two days) following hypoglycemic insult. Histological evaluation was performed one week after hypoglycemia. DCA treatment reduced hypoglycemia-induced oxidative stress, microglial activation, blood–brain barrier disruption, and neuronal death compared to the vehicle-treated hypoglycemia group. Therefore, our findings suggest that DCA may have the therapeutic potential to reduce hippocampal neuronal death after hypoglycemia.
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13
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Xing G, Ren M, Verma A. Divergent Induction of Branched-Chain Aminotransferases and Phosphorylation of Branched Chain Keto-Acid Dehydrogenase Is a Potential Mechanism Coupling Branched-Chain Keto-Acid-Mediated-Astrocyte Activation to Branched-Chain Amino Acid Depletion-Mediated Cognitive Deficit after Traumatic Brain Injury. J Neurotrauma 2018; 35:2482-2494. [PMID: 29764289 DOI: 10.1089/neu.2017.5496] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Deficient branched-chain amino acids (BCAAs) are implicated in cognitive dysfunction after traumatic brain injury (TBI). The mechanism remains unknown. BCAAs are catabolized by neuron-specific cytosolic and astrocyte-specific mitochondrial branched-chain aminotransferases (BCATc, BCATm) to generate glutamate and branched-chain keto-acids (BCKAs) that are metabolized by the mitochondrial branched-chain keto-acid dehydrogenase (BCKD) whose activity is regulated by its phosphorylation state. BCKD phosphorylation by BCKD kinase (BCKDK) inactivates BCKD and cause neurocognitive dysfunction, whereas dephosphorylation by specific phosphatase restores BCKD activity. Real-time polymerase chain reaction showed rapidly and significantly decreased BCATc messenger RNA (mRNA) levels, but significantly increased BCATm mRNA level post-CCI (controlled cortical impact). BCKD and BCKDK mRNA decreased significantly immediately after CCI-induced TBI (CCI) in the rat. Phosphorylated BCKD proteins (pBCKD) increased significantly in the ipsilateral-CCI hemisphere. Immunohistochemistry revealed significantly increased pBCKD proteins in ipsilateral astrocytes post-CCI. BCKD protein expression is higher in primarily cultured cortical neurons than in astrocytes, whereas pBCKD protein level is higher in astrocytes than in cortical neurons. Transforming growth factor beta treatment (10 μg/mL for 48 h) significantly increased pBCKD protein expression in astrocytes, whereas glutamate treatment (25 μM for 24 h) significantly decreased pBCKD protein in neurons. Because increased pBCKD would lead to increased BCKA accumulation, BCKA-mediated astrocyte activation, cell death, and cognitive dysfunction as found in maple syrup urine disease; thus, TBI may potentially induce cognitive deficit through diverting BCAA from glutamate production in neurons to BCKA production in astrocytes through the pBCKD-dependent mechanism.
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Affiliation(s)
- Guoqiang Xing
- 1 Department of Radiology and Imaging, Institute of Rehabilitation and Development of Brain Function , The Second Clinical Medical College of North Sichuan Medical College, Nanchong Central Hospital, Nanchong, China
| | - Ming Ren
- 2 Department of Neurology, Xuanwu Hospital, Capital Medical University , Beijing, China
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14
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Zhou J, Burns MP, Huynh L, Villapol S, Taub DD, Saavedra JM, Blackman MR. Temporal Changes in Cortical and Hippocampal Expression of Genes Important for Brain Glucose Metabolism Following Controlled Cortical Impact Injury in Mice. Front Endocrinol (Lausanne) 2017; 8:231. [PMID: 28955302 PMCID: PMC5601958 DOI: 10.3389/fendo.2017.00231] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 08/24/2017] [Indexed: 02/06/2023] Open
Abstract
Traumatic brain injury (TBI) causes transient increases and subsequent decreases in brain glucose utilization. The underlying molecular pathways are orchestrated processes and poorly understood. In the current study, we determined temporal changes in cortical and hippocampal expression of genes important for brain glucose/lactate metabolism and the effect of a known neuroprotective drug telmisartan on the expression of these genes after experimental TBI. Adult male C57BL/6J mice (n = 6/group) underwent sham or unilateral controlled cortical impact (CCI) injury. Their ipsilateral and contralateral cortex and hippocampus were collected 6 h, 1, 3, 7, 14, 21, and 28 days after injury. Expressions of several genes important for brain glucose utilization were determined by qRT-PCR. In results, (1) mRNA levels of three key enzymes in glucose metabolism [hexo kinase (HK) 1, pyruvate kinase, and pyruvate dehydrogenase (PDH)] were all increased 6 h after injury in the contralateral cortex, followed by decreases at subsequent times in the ipsilateral cortex and hippocampus; (2) capillary glucose transporter Glut-1 mRNA increased, while neuronal glucose transporter Glut-3 mRNA decreased, at various times in the ipsilateral cortex and hippocampus; (3) astrocyte lactate transporter MCT-1 mRNA increased, whereas neuronal lactate transporter MCT-2 mRNA decreased in the ipsilateral cortex and hippocampus; (4) HK2 (an isoform of hexokinase) expression increased at all time points in the ipsilateral cortex and hippocampus. GPR81 (lactate receptor) mRNA increased at various time points in the ipsilateral cortex and hippocampus. These temporal alterations in gene expression corresponded closely to the patterns of impaired brain glucose utilization reported in both TBI patients and experimental TBI rodents. The observed changes in hippocampal gene expression were delayed and prolonged, when compared with those in the cortex. The patterns of alterations were specific to different brain regions and exhibited different recovery periods following TBI. Oral administration of telmisartan (1 mg/kg, for 7 days, n = 10 per group) ameliorated cortical or hippocampal mRNA for Glut-1/3, MCT-1/2 and PDH in CCI mice. These data provide molecular evidence for dynamic alteration of multiple critical factors in brain glucose metabolism post-TBI and can inform further research for treating brain metabolic disorders post-TBI.
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Affiliation(s)
- June Zhou
- Research Service, Washington DC VA Medical Center, Washington, DC, United States
- Department of Biochemistry and Molecular Medicine, George Washington University School of Medicine, Washington, DC, United States
- *Correspondence: June Zhou,
| | - Mark P. Burns
- Department of Neuroscience, Georgetown University School of Medicine, Washington, DC, United States
| | - Linda Huynh
- Research Service, Washington DC VA Medical Center, Washington, DC, United States
| | - Sonia Villapol
- Department of Neuroscience, Georgetown University School of Medicine, Washington, DC, United States
| | - Daniel D. Taub
- Translational Medicine Section, Washington DC VA Medical Center, Washington, DC, United States
- Department of Biochemistry and Molecular and Cell Biology, Georgetown University School of Medicine, Washington, DC, United States
| | - Juan M. Saavedra
- Department of Pharmacology and Physiology, Georgetown University School of Medicine, Washington, DC, United States
| | - Marc R. Blackman
- Research Service, Washington DC VA Medical Center, Washington, DC, United States
- Department of Biochemistry and Molecular Medicine, George Washington University School of Medicine, Washington, DC, United States
- Department of Medicine George Washington University School of Medicine, Washington, DC, United States
- Department of Medicine, Georgetown University School of Medicine, Washington, DC, United States
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15
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Shijo K, Sutton RL, Ghavim SS, Harris NG, Bartnik-Olson BL. Metabolic fate of glucose in rats with traumatic brain injury and pyruvate or glucose treatments: A NMR spectroscopy study. Neurochem Int 2016; 102:66-78. [PMID: 27919624 DOI: 10.1016/j.neuint.2016.11.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 11/30/2016] [Accepted: 11/30/2016] [Indexed: 12/27/2022]
Abstract
Administration of sodium pyruvate (SP; 9.08 μmol/kg, i.p.), ethyl pyruvate (EP; 0.34 μmol/kg, i.p.) or glucose (GLC; 11.1 μmol/kg, i.p.) to rats after unilateral controlled cortical impact (CCI) injury has been reported to reduce neuronal loss and improve cerebral metabolism. In the present study these doses of each fuel or 8% saline (SAL; 5.47 nmoles/kg) were administered immediately and at 1, 3, 6 and 23 h post-CCI. At 24 h all CCI groups and non-treated Sham injury controls were infused with [1,2 13C] glucose for 68 min 13C nuclear magnetic resonance (NMR) spectra were obtained from cortex + hippocampus tissues from left (injured) and right (contralateral) hemispheres. All three fuels increased lactate labeling to a similar degree in the injured hemisphere. The amount of lactate labeled via the pentose phosphate and pyruvate recycling (PPP + PR) pathway increased in CCI-SAL and was not improved by SP, EP, and GLC treatments. Oxidative metabolism, as assessed by glutamate labeling, was reduced in CCI-SAL animals. The greatest improvement in oxidative metabolism was observed in animals treated with SP and fewer improvements after EP or GLC treatments. Compared to SAL, all three fuels restored glutamate and glutamine labeling via pyruvate carboxylase (PC), suggesting improved astrocyte metabolism following fuel treatment. Only SP treatments restored the amount of [4 13C] glutamate labeled by the PPP + PR pathway to sham levels. Milder injury effects in the contralateral hemisphere appear normalized by either SP or EP treatments, as increases in the total pool of 13C lactate and labeling of lactate in glycolysis, or decreases in the ratio of PC/PDH labeling of glutamine, were found only for CCI-SAL and CCI-GLC groups compared to Sham. The doses of SP, EP and GLC examined in this study all enhanced lactate labeling and restored astrocyte-specific PC activity but differentially affected neuronal metabolism after CCI injury. The restoration of astrocyte metabolism by all three fuel treatments may partially underlie their abilities to improve cerebral glucose utilization and to reduce neuronal loss following CCI injury.
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Affiliation(s)
- Katsunori Shijo
- Brain Injury Research Center, Department of Neurosurgery, David Geffen School of Medicine at UCLA, Los Angeles, Box 956901, CA, USA.
| | - Richard L Sutton
- Brain Injury Research Center, Department of Neurosurgery, David Geffen School of Medicine at UCLA, Los Angeles, Box 956901, CA, USA.
| | - Sima S Ghavim
- Brain Injury Research Center, Department of Neurosurgery, David Geffen School of Medicine at UCLA, Los Angeles, Box 956901, CA, USA.
| | - Neil G Harris
- Brain Injury Research Center, Department of Neurosurgery, David Geffen School of Medicine at UCLA, Los Angeles, Box 956901, CA, USA.
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16
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Thibodeau A, Geng X, Previch LE, Ding Y. Pyruvate dehydrogenase complex in cerebral ischemia-reperfusion injury. Brain Circ 2016; 2:61-66. [PMID: 30276274 PMCID: PMC6126256 DOI: 10.4103/2394-8108.186256] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Revised: 06/02/2016] [Accepted: 06/14/2016] [Indexed: 11/11/2022] Open
Abstract
Pyruvate dehydrogenase (PDH) complex is a mitochondrial matrix enzyme that serves a critical role in the conversion of anaerobic to aerobic cerebral energy. The regulatory complexity of PDH, coupled with its significant influence in brain metabolism, underscores its susceptibility to, and significance in, ischemia-reperfusion injury. Here, we evaluate proposed mechanisms of PDH-mediated neurodysfunction in stroke, including oxidative stress, altered regulatory enzymatic control, and loss of PDH activity. We also describe the neuroprotective influence of antioxidants, dichloroacetate, acetyl-L-carnitine, and combined therapy with ethanol and normobaric oxygen, explained in relation to PDH modulation. Our review highlights the significance of PDH impairment in stroke injury through an understanding of the mechanisms by which it is modulated, as well as an exploration of neuroprotective strategies available to limit its impairment.
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Affiliation(s)
- Alexa Thibodeau
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit, MI, USA
| | - Xiaokun Geng
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit, MI, USA.,China-America Institute of Neuroscience, Luhe Hospital, Capital Medical University, Beijing, China.,Department of Neurology, Luhe Hospital, Capital Medical University, Beijing, China
| | - Lauren E Previch
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit, MI, USA
| | - Yuchuan Ding
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit, MI, USA.,China-America Institute of Neuroscience, Luhe Hospital, Capital Medical University, Beijing, China
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17
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Jha MK, Lee IK, Suk K. Metabolic reprogramming by the pyruvate dehydrogenase kinase-lactic acid axis: Linking metabolism and diverse neuropathophysiologies. Neurosci Biobehav Rev 2016; 68:1-19. [PMID: 27179453 DOI: 10.1016/j.neubiorev.2016.05.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 04/11/2016] [Accepted: 05/09/2016] [Indexed: 12/12/2022]
Abstract
Emerging evidence indicates that there is a complex interplay between metabolism and chronic disorders in the nervous system. In particular, the pyruvate dehydrogenase (PDH) kinase (PDK)-lactic acid axis is a critical link that connects metabolic reprogramming and the pathophysiology of neurological disorders. PDKs, via regulation of PDH complex activity, orchestrate the conversion of pyruvate either aerobically to acetyl-CoA, or anaerobically to lactate. The kinases are also involved in neurometabolic dysregulation under pathological conditions. Lactate, an energy substrate for neurons, is also a recently acknowledged signaling molecule involved in neuronal plasticity, neuron-glia interactions, neuroimmune communication, and nociception. More recently, the PDK-lactic acid axis has been recognized to modulate neuronal and glial phenotypes and activities, contributing to the pathophysiologies of diverse neurological disorders. This review covers the recent advances that implicate the PDK-lactic acid axis as a novel linker of metabolism and diverse neuropathophysiologies. We finally explore the possibilities of employing the PDK-lactic acid axis and its downstream mediators as putative future therapeutic strategies aimed at prevention or treatment of neurological disorders.
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Affiliation(s)
- Mithilesh Kumar Jha
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 PLUS KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea; Department of Neurology, Division of Neuromuscular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - In-Kyu Lee
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Kyoungho Suk
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 PLUS KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea.
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18
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Watson WD, Buonora JE, Yarnell AM, Lucky JJ, D'Acchille MI, McMullen DC, Boston AG, Kuczmarski AV, Kean WS, Verma A, Grunberg NE, Cole JT. Impaired cortical mitochondrial function following TBI precedes behavioral changes. FRONTIERS IN NEUROENERGETICS 2014; 5:12. [PMID: 24550822 PMCID: PMC3912469 DOI: 10.3389/fnene.2013.00012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 12/09/2013] [Indexed: 01/30/2023]
Abstract
Traumatic brain injury (TBI) pathophysiology can be attributed to either the immediate, primary physical injury, or the delayed, secondary injury which begins minutes to hours after the initial injury and can persist for several months or longer. Because these secondary cascades are delayed and last for a significant time period post-TBI, they are primary research targets for new therapeutics. To investigate changes in mitochondrial function after a brain injury, both the cortical impact site and ipsilateral hippocampus of adult male rats 7 and 17 days after a controlled cortical impact (CCI) injury were examined. State 3, state 4, and uncoupler-stimulated rates of oxygen consumption, respiratory control ratios (RCRs) were measured and membrane potential quantified, and all were significantly decreased in 7 day post-TBI cortical mitochondria. By contrast, hippocampal mitochondria at 7 days showed only non-significant decreases in rates of oxygen consumption and membrane potential. NADH oxidase activities measured in disrupted mitochondria were normal in both injured cortex and hippocampus at 7 days post-CCI. Respiratory and phosphorylation capacities at 17 days post-CCI were comparable to naïve animals for both cortical and hippocampus mitochondria. However, unlike oxidative phosphorylation, membrane potential of mitochondria in the cortical lining of the impact site did not recover at 17 days, suggesting that while diminished cortical membrane potential at 17 days does not adversely affect mitochondrial capacity to synthesize ATP, it may negatively impact other membrane potential-sensitive mitochondrial functions. Memory status, as assessed by a passive avoidance paradigm, was not significantly impaired until 17 days after injury. These results indicate pronounced disturbances in cortical mitochondrial function 7 days after CCI which precede the behavioral impairment observed at 17 days.
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Affiliation(s)
- William D Watson
- Department of Neurology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - John E Buonora
- Department of Neurology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - Angela M Yarnell
- Department of Medical and Clinical Psychology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - Jessica J Lucky
- Department of Neurology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - Michaela I D'Acchille
- Department of Neurology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - David C McMullen
- Department of Neurology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - Andrew G Boston
- Department of Neurology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - Andrew V Kuczmarski
- Department of Neurology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - William S Kean
- Department of Neurology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - Ajay Verma
- Department of Neurology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - Neil E Grunberg
- Department of Medical and Clinical Psychology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
| | - Jeffrey T Cole
- Department of Neurology, Uniformed Services University of the Health Sciences Bethesda, MD, USA
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19
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Xing G, Barry ES, Benford B, Grunberg NE, Li H, Watson WD, Sharma P. Impact of repeated stress on traumatic brain injury-induced mitochondrial electron transport chain expression and behavioral responses in rats. Front Neurol 2013; 4:196. [PMID: 24376434 PMCID: PMC3859919 DOI: 10.3389/fneur.2013.00196] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 11/19/2013] [Indexed: 12/31/2022] Open
Abstract
A significant proportion of the military personnel returning from Iraq and Afghanistan conflicts have suffered from both mild traumatic brain injury (mTBI) and post-traumatic stress disorder. The mechanisms are unknown. We used a rat model of repeated stress and mTBI to examine brain activity and behavioral function. Adult male Sprague-Dawley rats were divided into four groups: Naïve; 3 days repeated tail-shock stress; lateral fluid percussion mTBI; and repeated stress followed by mTBI (S-mTBI). Open field activity, sensorimotor responses, and acoustic startle responses (ASRs) were measured at various time points after mTBI. The protein expression of mitochondrial electron transport chain (ETC) complex subunits (CI-V) and pyruvate dehydrogenase (PDHE1α1) were determined in four brain regions at day 7-post mTBI. Compared to Naïves, repeated stress decreased horizontal activity; repeated stress and mTBI both decreased vertical activity; and the mTBI and S-mTBI groups were impaired in sensorimotor and ASRs. Repeated stress significantly increased CI, CII, and CIII protein levels in the prefrontal cortex (PFC), but decreased PDHE1α1 protein in the PFC and cerebellum, and decreased CIV protein in the hippocampus. The mTBI treatment decreased CV protein levels in the ipsilateral hippocampus. The S-mTBI treatment resulted in increased CII, CIII, CIV, and CV protein levels in the PFC, increased CI level in the cerebellum, and increased CIII and CV levels in the cerebral cortex, but decreased CI, CII, CIV, and PDHE1α1 protein levels in the hippocampus. Thus, repeated stress or mTBI alone differentially altered ETC expression in heterogeneous brain regions. Repeated stress followed by mTBI had synergistic effects on brain ETC expression, and resulted in more severe behavioral deficits. These results suggest that repeated stress could have contributed to the high incidence of long-term neurologic and neuropsychiatric morbidity in military personnel with or without mTBI.
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Affiliation(s)
- Guoqiang Xing
- Department of Anesthesiology, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - Erin S Barry
- Department of Medical and Clinical Psychology, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - Brandi Benford
- Department of Anesthesiology, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - Neil E Grunberg
- Department of Medical and Clinical Psychology, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - He Li
- Department of Psychiatry, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - William D Watson
- Department of Neurology, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | - Pushpa Sharma
- Department of Anesthesiology, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
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20
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Khatri N, Man HY. Synaptic activity and bioenergy homeostasis: implications in brain trauma and neurodegenerative diseases. Front Neurol 2013; 4:199. [PMID: 24376435 PMCID: PMC3858785 DOI: 10.3389/fneur.2013.00199] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 11/26/2013] [Indexed: 12/14/2022] Open
Abstract
Powered by glucose metabolism, the brain is the most energy-demanding organ in our body. Adequate ATP production and regulation of the metabolic processes are essential for the maintenance of synaptic transmission and neuronal function. Glutamatergic synaptic activity utilizes the largest portion of bioenergy for synaptic events including neurotransmitter synthesis, vesicle recycling, and most importantly, the postsynaptic activities leading to channel activation and rebalancing of ionic gradients. Bioenergy homeostasis is coupled with synaptic function via activities of the sodium pumps, glutamate transporters, glucose transport, and mitochondria translocation. Energy insufficiency is sensed by the AMP-activated protein kinase (AMPK), a master metabolic regulator that stimulates the catalytic process to enhance energy production. A decline in energy supply and a disruption in bioenergy homeostasis play a critical role in multiple neuropathological conditions including ischemia, stroke, and neurodegenerative diseases including Alzheimer’s disease and traumatic brain injuries.
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Affiliation(s)
- Natasha Khatri
- Department of Biology, Boston University , Boston, MA , USA ; Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine , Boston, MA , USA
| | - Heng-Ye Man
- Department of Biology, Boston University , Boston, MA , USA ; Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine , Boston, MA , USA
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21
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Bartnik-Olson BL, Harris NG, Shijo K, Sutton RL. Insights into the metabolic response to traumatic brain injury as revealed by (13)C NMR spectroscopy. FRONTIERS IN NEUROENERGETICS 2013; 5:8. [PMID: 24109452 PMCID: PMC3790078 DOI: 10.3389/fnene.2013.00008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 09/12/2013] [Indexed: 12/11/2022]
Abstract
The present review highlights critical issues related to cerebral metabolism following traumatic brain injury (TBI) and the use of (13)C labeled substrates and nuclear magnetic resonance (NMR) spectroscopy to study these changes. First we address some pathophysiologic factors contributing to metabolic dysfunction following TBI. We then examine how (13)C NMR spectroscopy strategies have been used to investigate energy metabolism, neurotransmission, the intracellular redox state, and neuroglial compartmentation following injury. (13)C NMR spectroscopy studies of brain extracts from animal models of TBI have revealed enhanced glycolytic production of lactate, evidence of pentose phosphate pathway (PPP) activation, and alterations in neuronal and astrocyte oxidative metabolism that are dependent on injury severity. Differential incorporation of label into glutamate and glutamine from (13)C labeled glucose or acetate also suggest TBI-induced adaptations to the glutamate-glutamine cycle.
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Prins M, Greco T, Alexander D, Giza CC. The pathophysiology of traumatic brain injury at a glance. Dis Model Mech 2013; 6:1307-15. [PMID: 24046353 PMCID: PMC3820255 DOI: 10.1242/dmm.011585] [Citation(s) in RCA: 238] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Traumatic brain injury (TBI) is defined as an impact, penetration or rapid movement of the brain within the skull that results in altered mental state. TBI occurs more than any other disease, including breast cancer, AIDS, Parkinson's disease and multiple sclerosis, and affects all age groups and both genders. In the US and Europe, the magnitude of this epidemic has drawn national attention owing to the publicity received by injured athletes and military personnel. This increased public awareness has uncovered a number of unanswered questions concerning TBI, and we are increasingly aware of the lack of treatment options for a crisis that affects millions. Although each case of TBI is unique and affected individuals display different degrees of injury, different regional patterns of injury and different recovery profiles, this review and accompanying poster aim to illustrate some of the common underlying neurochemical and metabolic responses to TBI. Recognition of these recurrent features could allow elucidation of potential therapeutic targets for early intervention.
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Affiliation(s)
- Mayumi Prins
- Department of Neurosurgery, UCLA, Los Angeles, CA 90095, USA
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23
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Arun P, Abu-Taleb R, Oguntayo S, Wang Y, Valiyaveettil M, Long JB, Nambiar MP. Acute mitochondrial dysfunction after blast exposure: potential role of mitochondrial glutamate oxaloacetate transaminase. J Neurotrauma 2013; 30:1645-51. [PMID: 23600763 DOI: 10.1089/neu.2012.2834] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Use of improvised explosive devices has significantly increased the incidence of traumatic brain injury (TBI) and associated neuropsychiatric deficits in the recent wars in Iraq and Afghanistan. Acute deleterious effects of single and repeated blast exposure can lead to long-term neurobiological effects and neuropsychiatric deficits. Using in vitro and in vivo shock tube models of blast-induced TBI, we studied changes in mitochondrial energy metabolism after blast exposure. Single and repeated blast exposures in vitro resulted in significant decreases in neuronal adenosine triphosphate (ATP) levels at 6 h post-blast that returned towards normal levels by 24 h. Similar changes in ATP also were observed in the cerebral cortices of mice subjected to single and repeated blast exposures. In neurons, mitochondrial glutamate oxaloacetate transaminase (GOT2) plays a critical role in metabolism and energy production. Proteomic analysis of brain cortices showed a significant decrease in GOT2 levels 6 h after repeated blast exposures, which was further confirmed by Western blotting. Western blot analysis of GOT2 and pyruvate dehydrogenase in the cortex showed direct correlation only between GOT2 and ATP levels. Activity of GOT2 in the isolated cortical mitochondria also showed significant decrease at 6 h supporting the results of proteomic and Western blot analyses. Knowing the significant role of GOT2 in the neuronal mitochondrial energy metabolism, it is quite likely that the down regulation of GOT2 after blast exposure is playing a significant role in mitochondrial dysfunction after blast exposure.
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Affiliation(s)
- Peethambaran Arun
- Blast-Induced Neurotrauma Branch, Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research , Silver Spring, Maryland
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24
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Jha MK, Jeon S, Suk K. Pyruvate Dehydrogenase Kinases in the Nervous System: Their Principal Functions in Neuronal-glial Metabolic Interaction and Neuro-metabolic Disorders. Curr Neuropharmacol 2013; 10:393-403. [PMID: 23730261 PMCID: PMC3520047 DOI: 10.2174/157015912804143586] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 08/10/2012] [Accepted: 08/28/2012] [Indexed: 01/03/2023] Open
Abstract
Metabolism is involved directly or indirectly in all processes conducted in living cells. The brain, popularly viewed as a neuronal-glial complex, gets most of its energy from the oxygen-dependent metabolism of glucose, and the mitochondrial pyruvate dehydrogenase complex (PDC) plays a key regulatory role during the oxidation of glucose. Pyruvate dehydrogenase kinase (also called PDC kinase or PDK) is a kinase that regulates glucose metabolism by switching off PDC. Four isoforms of PDKs with tissue specific activities have been identified. The metabolisms of neurons and glial cells, especially, those of astroglial cells, are interrelated, and these cells function in an integrated fashion. The energetic coupling between neuronal and astroglial cells is essential to meet the energy requirements of the brain in an efficient way. Accumulating evidence suggests that alterations in the PDKs and/or neuron-astroglia metabolic interactions are associated with the development of several neurological disorders. Here, the authors review the results of recent research efforts that have shed light on the functions of PDKs in the nervous system, particularly on neuron-glia metabolic interactions and neuro-metabolic disorders.
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Affiliation(s)
- Mithilesh Kumar Jha
- Department of Pharmacology, Brain Science & Engineering Institute, Kyungpook National University School of Medicine, Daegu, Korea
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25
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Feng JF, He LL, Li D, Yuan LH, Yu HL, Ma WW, Yang Y, Xi YD, Ding J, Xiao YX, Xiao R. Antagonizing effects of soybean isoflavones on β-amyloid peptide-induced oxidative damage in neuron mitochondria of rats. Basic Clin Pharmacol Toxicol 2012; 111:248-53. [PMID: 22551092 DOI: 10.1111/j.1742-7843.2012.00900.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2011] [Accepted: 04/05/2012] [Indexed: 11/29/2022]
Abstract
Soybean isoflavone (SIF) has been demonstrated to have neuroprotective effects induced by β-amyloid peptides (Aβ) through suppressing oxidative stress; however, the explicit mechanisms still remain uncovered. In the present study, 32 Wistar rats were randomly divided into four groups: an Aβ1-42-treated group, a SIF + Aβ1-42 group, a SIF-treated group and a control group. We measured the protein content of 8-hydroxydeoxyguanosine (8-OhdG) and mRNA expression of 8-oxoguanine DNA glycosylase (OGG1). The protein expression of OGG1, Bcl-xl, Bad, beta subunit of ATP synthase (ATPB) and pyruvate dehydrogenase (PDH) in brain was also measured. The results showed that the level of 8-OHdG in both SIF groups was significantly decreased compared to the Aβ1-42-treated group (p < 0.05), while the mRNA and protein expression of OGG1 in the SIF + Aβ1-42 groups were up-regulated compared with the Aβ1-42-treated groups (p < 0.05). The expression of Bcl-xl was up-regulated in the SIF-treated group compared with the Aβ1-42-treated groups (p < 0.05), while the expression of Bad was down-regulated in the two SIF-treated groups (p < 0.05). Aβ1-42 significantly down-regulated the expression of ATPase and PDH proteins compared with the control group (p < 0.05). SIF reversed the down-regulation effects on the mitochondrial energy metabolic enzymes induced by Aβ1-42 (p < 0.05) in the rats. These results suggest that SIF alleviate the oxidative stress in neurons and mitochondria of rat brains mediated by Aβ1-42, and these protective effects might be associated with the regulation of OGG1, Bad, Bcl-xl, ATPB and PDH.
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Affiliation(s)
- Jin-Fang Feng
- Department of Nutrition & Food Hygiene, School of Public Health and Family Medicine, Capital Medical University, Beijing, China
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26
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Xing G, Ren M, O'Neill JT, Sharma P, Verma A, Watson WD. Pyruvate dehydrogenase phosphatase1 mRNA expression is divergently and dynamically regulated between rat cerebral cortex, hippocampus and thalamus after traumatic brain injury: a potential biomarker of TBI-induced hyper- and hypo-glycaemia and neuronal vulnerability. Neurosci Lett 2012; 525:140-5. [PMID: 22884618 DOI: 10.1016/j.neulet.2012.07.055] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 06/30/2012] [Accepted: 07/21/2012] [Indexed: 12/12/2022]
Abstract
Cerebral pyruvate depletion and lactate acidosis are common metabolic characteristics of patients with traumatic brain injury (TBI) and are associated with poor prognosis. Pyruvate dehydrogenase (PDH) is the rate-limiting enzyme coupling glycolysis to mitochondrial tricarboxylic acid (TCA) cycle. Brain PDH activity is regulated by its phosphorylation status and other effectors. Phosphorylation of PDH E1α1 subunit by PDH kinase inhibits PDH activity while dephosphorylation of phosphorylated PDHE1α1 by PDH phosphatase (PDP1) restores PDH activity. In situ hybridization showed that PDP1 mRNA is highly expressed in the cerebral cortex, hippocampus and thalamus of rat. Controlled cortical impact (CCI) induced a significant increase in PDP1 mRNA expression in ipsilateral cerebral cortex at 4 h (P<0.05) and 24 h post CCI (P<0.01) that returned to basal level 72 h post CCI. PDP1 mRNA level increased transiently in ipsilateral hippocampal dentate gyrus and CA1-3 subfields 4 h post CCI (P<0.01) but decreased significantly 24 h and 72 h (P<0.01) post CCI, coinciding with a marked increase in neuronal apoptosis in ipsilateral hippocampus 24 h post CCI. PDP1 mRNA expression in thalamus and other subcortical regions decreased persistently post CCI. Contralateral CCI and craniotomy showed similar effects on PDP1 mRNA expression as ipsilateral CCI. Because GFAP mRNA expression was induced in brain regions where PDP1 expression was altered, further study should determine the potential relationship between astrocyte activation, PDP1 alteration, and pyruvate metabolism following TBI.
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Affiliation(s)
- Guoqiang Xing
- Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4799, USA.
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27
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Dalgard CL, Cole JT, Kean WS, Lucky JJ, Sukumar G, McMullen DC, Pollard HB, Watson WD. The cytokine temporal profile in rat cortex after controlled cortical impact. Front Mol Neurosci 2012; 5:6. [PMID: 22291617 PMCID: PMC3265961 DOI: 10.3389/fnmol.2012.00006] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 01/12/2012] [Indexed: 12/30/2022] Open
Abstract
Cerebral inflammatory responses may initiate secondary cascades following traumatic brain injury (TBI). Changes in the expression of both cytokines and chemokines may activate, regulate, and recruit innate and adaptive immune cells associated with secondary degeneration, as well as alter a host of other cellular processes. In this study, we quantified the temporal expression of a large set of inflammatory mediators in rat cortical tissue after brain injury. Following a controlled cortical impact (CCI) on young adult male rats, cortical and hippocampal tissue of the injured hemisphere and matching contralateral material was harvested at early (4, 12, and 24 hours) and extended (3 and 7 days) time points post-procedure. Naïve rats that received only anesthesia were used as controls. Processed brain homogenates were assayed for chemokine and cytokine levels utilizing an electrochemiluminescence-based multiplex ELISA platform. The temporal profile of cortical tissue samples revealed a multi-phasic injury response following brain injury. CXCL1, IFN-γ, TNF-α levels significantly peaked at four hours post-injury compared to levels found in naïve or contralateral tissue. CXCL1, IFN-γ, and TNF-α levels were then observed to decrease at least 3-fold by 12 hours post-injury. IL-1β, IL-4, and IL-13 levels were also significantly elevated at four hours post-injury although their expression did not decrease more than 3-fold for up to 24 hours post-injury. Additionally, IL-1β and IL-4 levels displayed a biphasic temporal profile in response to injury, which may suggest their involvement in adaptive immune responses. Interestingly, peak levels of CCL2 and CCL20 were not observed until after four hours post-injury. CCL2 levels in injured cortical tissue were significantly higher than peak levels of any other inflammatory mediator measured, thus suggesting a possible use as a biomarker. Fully elucidating chemokine and cytokine signaling properties after brain injury may provide increased insight into a number of secondary cascade events that are initiated or regulated by inflammatory responses.
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Affiliation(s)
- Clifton L Dalgard
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda MD, USA
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28
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Xing G, Ren M, O'Neill JT, Verma A, Watson WD. Controlled cortical impact injury and craniotomy result in divergent alterations of pyruvate metabolizing enzymes in rat brain. Exp Neurol 2011; 234:31-8. [PMID: 22193111 DOI: 10.1016/j.expneurol.2011.12.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 12/04/2011] [Indexed: 01/04/2023]
Abstract
Dysregulated glucose metabolism and energy deficit is a characteristic of severe traumatic brain injury (TBI) but its mechanism remains to be fully elucidated. Phosphorylation of pyruvate dehydrogenase (PDH) is the rate-limiting mitochondria enzyme reaction coupling glycolysis to the tricarboxylic acid cycle. Phosphorylation of PDH E1α1 subunit catalyzed by PDH kinase (PDK) inhibits PDH activity, effectively decoupling aerobic glycolysis whereas dephosphorylation of phosphorylated PDHE1α1 by PDH phosphatase (PDP) restores PDH activity. We recently reported altered expression and phosphorylation of pyruvate dehydrogenase (PDH) following TBI. However, little is known about PDK and PDP involvement. We determined PDK (PDK1-4) and PDP isoenzyme (PDP1-2) mRNA and protein expression in rat brain using immunohistochemistry and in situ hybridization techniques. We also quantified PDK and PDP mRNA and protein levels in rat brain following TBI using quantitative real-time PCR and Western blot, respectively. Controlled cortical impact-induced TBI (CCI-TBI) and craniotomy significantly enhanced PDK1-2 isoenzyme mRNA expression level but significantly suppressed PDP1 and PDK4 mRNA expression after the injury (4h to 7days). CCI-TBI and craniotomy also significantly increased PDK1-4 isoenzyme protein expression but suppressed PDP1-2 protein expression in rat brain. In summary, the divergent changes between PDK and PDP expression indicate imbalance between PDK and PDP activities that would favor increased PDHE1α1 phosphorylation and enzyme inhibition contributing to impaired oxidative glucose metabolism in TBI as well as craniotomy.
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Affiliation(s)
- Guoqiang Xing
- Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4799, USA.
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29
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Cole JT, Yarnell A, Kean WS, Gold E, Lewis B, Ren M, McMullen DC, Jacobowitz DM, Pollard HB, O'Neill JT, Grunberg NE, Dalgard CL, Frank JA, Watson WD. Craniotomy: true sham for traumatic brain injury, or a sham of a sham? J Neurotrauma 2011; 28:359-69. [PMID: 21190398 DOI: 10.1089/neu.2010.1427] [Citation(s) in RCA: 212] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract Neurological dysfunction after traumatic brain injury (TBI) is caused by both the primary injury and a secondary cascade of biochemical and metabolic events. Since TBI can be caused by a variety of mechanisms, numerous models have been developed to facilitate its study. The most prevalent models are controlled cortical impact and fluid percussion injury. Both typically use "sham" (craniotomy alone) animals as controls. However, the sham operation is objectively damaging, and we hypothesized that the craniotomy itself may cause a unique brain injury distinct from the impact injury. To test this hypothesis, 38 adult female rats were assigned to one of three groups: control (anesthesia only); craniotomy performed by manual trephine; or craniotomy performed by electric dental drill. The rats were then subjected to behavioral testing, imaging analysis, and quantification of cortical concentrations of cytokines. Both craniotomy methods generate visible MRI lesions that persist for 14 days. The initial lesion generated by the drill technique is significantly larger than that generated by the trephine. Behavioral data mirrored lesion volume. For example, drill rats have significantly impaired sensory and motor responses compared to trephine or naïve rats. Finally, of the seven tested cytokines, KC-GRO and IFN-γ showed significant increases in both craniotomy models compared to naïve rats. We conclude that the traditional sham operation as a control confers profound proinflammatory, morphological, and behavioral damage, which confounds interpretation of conventional experimental brain injury models. Any experimental design incorporating "sham" procedures should distinguish among sham, experimentally injured, and healthy/naïve animals, to help reduce confounding factors.
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Affiliation(s)
- Jeffrey T Cole
- Department of Neurology, Uniformed Services University of the Health Sciences, Silver Spring, Maryland, USA.
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30
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Shi X, Lu XG, Zhan LB, Qi X, Liang LN, Hu SY, Yan Y, Zhao SY, Sui H, Zhang FL. The effects of the Chinese medicine ZiBu PiYin recipe on the hippocampus in a rat model of diabetes-associated cognitive decline: a proteomic analysis. Diabetologia 2011; 54:1888-99. [PMID: 21509442 DOI: 10.1007/s00125-011-2147-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Accepted: 03/21/2011] [Indexed: 12/25/2022]
Abstract
AIMS/HYPOTHESIS Increasing evidence suggests that diabetes is associated with an enhanced risk of cognitive decline. The precise mechanisms underlying diabetes-associated cognitive decline (DACD) remain unclear. Here we investigated the molecular changes associated with DACD using a comparative proteomics study of hippocampus in a rat model of type 2 diabetes. In addition, we tested the effects of the Chinese medicine ZiBu PiYin recipe (ZBPYR) on DACD. METHODS The hippocampus was dissected from control, diabetic and diabetic rats treated with ZBPYR (DM/ZBPYR). Soluble proteins were separated using fluorescence-based difference gel electrophoresis. Protein spots were visualised with fluorescent dyes and spot density was compared between each pair of groups. Proteins of interest were identified using mass spectrometry. Proteins of specific interest were also tested by western blot and real-time PCR analysis. RESULTS We found 13 spots that were altered between control and diabetes groups, and 12 spots that were changed between diabetes and DM/ZBPYR groups. The identities of nine proteins were determined by mass spectrometry. The identified proteins were largely involved in energy metabolism, cytoskeleton regulation and oxidative stress. The protein alterations observed in the diabetes group were ameliorated to varying degrees following ZBPYR treatment. CONCLUSIONS/INTERPRETATION The protein changes identified in hippocampus from a rat model of type 2 diabetes suggest that specific cellular alterations contribute to DACD. The Chinese medicine ZBPYR was found to affect multiple targets and partially repaired the original cellular balance. This study may provide important insights into the molecular events underlying DACD and allow the identification of novel therapeutic targets.
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Affiliation(s)
- X Shi
- The Second Affiliated Hospital, Dalian Medical University, Dalian, Liaoning Province 116023, China
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31
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Scafidi S, Racz J, Hazelton J, McKenna MC, Fiskum G. Neuroprotection by acetyl-L-carnitine after traumatic injury to the immature rat brain. Dev Neurosci 2011; 32:480-7. [PMID: 21228558 DOI: 10.1159/000323178] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2010] [Accepted: 11/25/2010] [Indexed: 01/05/2023] Open
Abstract
Traumatic brain injury (TBI) is the leading cause of mortality and morbidity in children and is characterized by reduced aerobic cerebral energy metabolism early after injury, possibly due to impaired activity of the pyruvate dehydrogenase complex. Exogenous acetyl-L-carnitine (ALCAR) is metabolized in the brain to acetyl coenzyme A and subsequently enters the tricarboxylic acid cycle. ALCAR administration is neuroprotective in animal models of cerebral ischemia and spinal cord injury, but has not been tested for TBI. This study tested the hypothesis that treatment with ALCAR during the first 24 h following TBI in immature rats improves neurologic outcome and reduces cortical lesion volume. Postnatal day 21-22 male rats were isoflurane anesthetized and used in a controlled cortical impact model of TBI to the left parietal cortex. At 1, 4, 12 and 23 h after injury, rats received ALCAR (100 mg/kg, intraperitoneally) or drug vehicle (normal saline). On days 3-7 after surgery, behavior was assessed using beam walking and novel object recognition tests. On day 7, rats were transcardially perfused and brains were harvested for histological assessment of cortical lesion volume, using stereology. Injured animals displayed a significant increase in foot slips compared to sham-operated rats (6 ± 1 SEM vs. 2 ± 0.2 on day 3 after trauma; n = 7; p < 0.05). The ALCAR-treated rats were not different from shams and had fewer foot slips compared to vehicle-treated animals (2 ± 0.4; n = 7; p< 0.05). The frequency of investigating a novel object for saline-treated TBI animals was reduced compared to shams (45 ± 5% vs. 65 ± 10%; n = 7; p < 0.05), whereas the frequency of investigation for TBI rats treated with ALCAR was not significantly different from that of shams but significantly higher than that of saline-treated TBI rats (68 ± 7; p < 0.05). The left parietal cortical lesion volume, expressed as a percentage of the volume of tissue in the right hemisphere, was significantly smaller in ALCAR-treated than in vehicle-treated TBI rats (14 ± 5% vs. 28 ± 6%; p < 0.05). We conclude that treatment with ALCAR during the first 24 h after TBI improves behavioral outcomes and reduces brain lesion volume in immature rats within the first 7 days after injury.
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Affiliation(s)
- Susanna Scafidi
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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32
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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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33
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Dash PK, Orsi SA, Zhang M, Grill RJ, Pati S, Zhao J, Moore AN. Valproate administered after traumatic brain injury provides neuroprotection and improves cognitive function in rats. PLoS One 2010; 5:e11383. [PMID: 20614021 PMCID: PMC2894851 DOI: 10.1371/journal.pone.0011383] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 06/09/2010] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Traumatic brain injury (TBI) initiates a complex series of neurochemical and signaling changes that lead to pathological events including neuronal hyperactivity, excessive glutamate release, inflammation, increased blood-brain barrier (BBB) permeability and cerebral edema, altered gene expression, and neuronal dysfunction. It is believed that a drug combination, or a single drug acting on multiple targets, may be an effective strategy to treat TBI. Valproate, a widely used antiepileptic drug, has a number of targets including GABA transaminase, voltage-gated sodium channels, glycogen synthase kinase (GSK)-3, and histone deacetylases (HDACs), and therefore may attenuate a number of TBI-associated pathologies. METHODOLOGY/PRINCIPAL FINDINGS Using a rodent model of TBI, we tested if post-injury administration of valproate can decrease BBB permeability, reduce neural damage and improve cognitive outcome. Dose-response studies revealed that systemic administration of 400 mg/kg (i.p.), but not 15, 30, 60 or 100 mg/kg, increases histone H3 and H4 acetylation, and reduces GSK-3 activity, in the hippocampus. Thirty min post-injury administration of 400 mg/kg valproate improved BBB integrity as indicated by a reduction in Evans Blue dye extravasation. Consistent with its dose response to inhibit GSK-3 and HDACs, valproate at 400 mg/kg, but not 100 mg/kg, reduced TBI-associated hippocampal dendritic damage, lessened cortical contusion volume, and improved motor function and spatial memory. These behavioral improvements were not observed when SAHA (suberoylanilide hydroxamic acid), a selective HDAC inhibitor, was administered. CONCLUSION/SIGNIFICANCE Our findings indicate that valproate given soon after TBI can be neuroprotective. As clinically proven interventions that can be used to minimize the damage following TBI are not currently available, the findings from this report support the further testing of valproate as an acute therapeutic strategy.
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Affiliation(s)
- Pramod K Dash
- Department of Neurobiology and Anatomy, University of Texas Health Science Center at Houston, Houston, Texas, United States of America.
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Meierhans R, Béchir M, Ludwig S, Sommerfeld J, Brandi G, Haberthür C, Stocker R, Stover JF. Brain metabolism is significantly impaired at blood glucose below 6 mM and brain glucose below 1 mM in patients with severe traumatic brain injury. Crit Care 2010; 14:R13. [PMID: 20141631 PMCID: PMC2875528 DOI: 10.1186/cc8869] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Revised: 12/20/2009] [Accepted: 02/08/2010] [Indexed: 12/25/2022] Open
Abstract
INTRODUCTION The optimal blood glucose target following severe traumatic brain injury (TBI) must be defined. Cerebral microdialysis was used to investigate the influence of arterial blood and brain glucose on cerebral glucose, lactate, pyruvate, glutamate, and calculated indices of downstream metabolism. METHODS In twenty TBI patients, microdialysis catheters inserted in the edematous frontal lobe were dialyzed at 1 microl/min, collecting samples at 60 minute intervals. Occult metabolic alterations were determined by calculating the lactate- pyruvate (L/P), lactate- glucose (L/Glc), and lactate- glutamate (L/Glu) ratios. RESULTS Brain glucose was influenced by arterial blood glucose. Elevated L/P and L/Glc were significantly reduced at brain glucose above 1 mM, reaching lowest values at blood and brain glucose levels between 6-9 mM (P < 0.001). Lowest cerebral glutamate was measured at brain glucose 3-5 mM with a significant increase at brain glucose below 3 mM and above 6 mM. While L/Glu was significantly increased at low brain glucose levels, it was significantly decreased at brain glucose above 5 mM (P < 0.001). Insulin administration increased brain glutamate at low brain glucose, but prevented increase in L/Glu. CONCLUSIONS Arterial blood glucose levels appear to be optimal at 6-9 mM. While low brain glucose levels below 1 mM are detrimental, elevated brain glucose are to be targeted despite increased brain glutamate at brain glucose >5 mM. Pathogenity of elevated glutamate appears to be relativized by L/Glu and suggests to exclude insulin- induced brain injury.
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Affiliation(s)
- Roman Meierhans
- Surgical Intensive Care, University Hospital Zürich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - Markus Béchir
- Surgical Intensive Care, University Hospital Zürich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - Silke Ludwig
- Surgical Intensive Care, University Hospital Zürich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - Jutta Sommerfeld
- Surgical Intensive Care, University Hospital Zürich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - Giovanna Brandi
- Surgical Intensive Care, University Hospital Zürich, Rämistrasse 100, 8091 Zürich, Switzerland
- Ospedale Maggiore Policlinico Milano, Via Francesco Sforza, 28, I-20122 Milano, Italy
| | - Christoph Haberthür
- Surgical Intensive Care, Luzerner Kantonsspital, 6000 Luzern 16, Switzerland
| | - Reto Stocker
- Surgical Intensive Care, University Hospital Zürich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - John F Stover
- Surgical Intensive Care, University Hospital Zürich, Rämistrasse 100, 8091 Zürich, Switzerland
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Mccurley AT, Callard GV. Time course Analysis of Gene expression patterns in ZebrafIsh Eye during Optic Nerve Regeneration. J Exp Neurosci 2010. [DOI: 10.4137/jen.s5006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
It is well-established that neurons in the adult mammalian central nervous system (CNS) are terminally differentiated and, if injured, will be unable to regenerate their connections. In contrast to mammals, zebrafish and other teleosts display a robust neuroregenerative response. Following optic nerve crush (ONX), retinal ganglion cells (RGC) regrow their axons to synapse with topographically correct targets in the optic tectum, such that vision is restored in ~21 days. What accounts for these differences between teleostean and mammalian responses to neural injury is not fully understood. A time course analysis of global gene expression patterns in the zebrafish eye after ONX can help to elucidate cellular and molecular mechanisms that contribute to a successful neuroregeneration. To define different phases of regeneration after ONX, alpha tubulin 1 ( tuba1) and growth-associated protein 43 ( gap43), markers previously shown to correspond to morphophological events, were measured by real time quantitative PCR (qPCR). Microarray analysis was then performed at defined intervals (6 hours, 1, 4, 12, and 21 days) post-ONX and compared to SHAM. Results show that optic nerve damage induces multiple, phase-related transcriptional programs, with the maximum number of genes changed and highest fold-change occurring at 4 days. Several functional groups affected by optic nerve regeneration, including cell adhesion, apoptosis, cell cycle, energy metabolism, ion channel activity, and calcium signaling, were identified. Utilizing the whole eye allowed us to identify signaling contributions from the vitreous, immune and glial cells as well as the neural cells of the retina. Comparisons between our dataset and transcriptional profiles from other models of regeneration in zebrafish retina, heart and fin revealed a subset of commonly regulated transcripts, indicating shared mechanisms in different regenerating tissues. Knowledge of gene expression patterns in all components of the eye in a model of successful regeneration provides an entry point for functional analyses, and will help in devising hypotheses for testing normal and toxic regulatory factors.
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Affiliation(s)
- Amy T. Mccurley
- Department of Biology, Boston University, 5 cummington street, Boston, MA 02215 USA
| | - Gloria V. Callard
- Department of Biology, Boston University, 5 cummington street, Boston, MA 02215 USA
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