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Liharska LE, Park YJ, Ziafat K, Wilkins L, Silk H, Linares LM, Vornholt E, Sullivan B, Cohen V, Kota P, Feng C, Cheng E, Moya E, Thompson RC, Johnson JS, Rieder MK, Huang J, Scarpa J, Hashemi A, Polanco J, Levin MA, Nadkarni GN, Sebra R, Crary J, Schadt EE, Beckmann ND, Kopell BH, Charney AW. A study of gene expression in the living human brain. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.04.21.23288916. [PMID: 37163086 PMCID: PMC10168405 DOI: 10.1101/2023.04.21.23288916] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A goal of medical research is to determine the molecular basis of human brain health and illness. One way to achieve this goal is through observational studies of gene expression in human brain tissue. Due to the unavailability of brain tissue from living people, most such studies are performed using tissue from postmortem brain donors. An assumption underlying this practice is that gene expression in the postmortem human brain is an accurate representation of gene expression in the living human brain. Here, this assumption - which, until now, had not been adequately tested - is tested by comparing human prefrontal cortex gene expression between 275 living samples and 243 postmortem samples. Expression levels differed significantly for nearly 80% of genes, and a systematic examination of alternative explanations for this observation determined that these differences are not a consequence of cell type composition, RNA quality, postmortem interval, age, medication, morbidity, symptom severity, tissue pathology, sample handling, batch effects, or computational methods utilized. Analyses integrating the data generated for this study with data from earlier landmark studies that used tissue from postmortem brain donors showed that postmortem brain gene expression signatures of neurological and mental illnesses, as well as of normal traits such as aging, may not be accurate representations of these gene expression signatures in the living brain. By using tissue from large cohorts living people, future observational studies of human brain biology have the potential to (1) determine the medical research questions that can be addressed using postmortem tissue as a proxy for living tissue and (2) expand the scope of medical research to include questions about the molecular basis of human brain health and illness that can only be addressed in living people (e.g., "What happens at the molecular level in the brain as a person experiences an emotion?").
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2
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Javan GT, Hanson E, Finley SJ, Visonà SD, Osculati A, Ballantyne J. Identification of cadaveric liver tissues using thanatotranscriptome biomarkers. Sci Rep 2020; 10:6639. [PMID: 32313164 PMCID: PMC7170907 DOI: 10.1038/s41598-020-63727-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 03/31/2020] [Indexed: 01/10/2023] Open
Abstract
Thanatotranscriptome studies involve the examination of mRNA transcript abundance and gene expression patterns in the internal organs of deceased humans. Postmortem gene expression is indicative of the cellular status of a corpse at the time of death, a portion of which may represent a cascade of molecular events occasioned by death. Specific gene biomarkers identify perceptible transcriptional changes induced by stochastic responses to the cessation of biological functions. Transcriptome analyses of postmortem mRNA from a tissue fragment may determine unique molecular identifiers for specific organs and demonstrate unique patterns of gene expression that can provide essential contextual anatomical information. We evaluated the impact of targeted transcriptome analysis using RNA sequencing to reveal global changes in postmortem gene expression in liver tissues from 27 Italian and United States corpses: 3.5-hour-old to 37-day-old. We found that our single blind study using eight liver tissue-specific gene biomarkers (e.g. AMBP and AHSG) is highly specific, with autopsy-derived organ samples correctly identified as tissues originating from postmortem livers. The results demonstrate that 98–100% of sequencing reads were mapped to these liver biomarkers. Our findings indicate that gene expression signatures of mRNA exposed up to 37 days of autolysis, can be used to validate the putative identity of tissue fragments.
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Affiliation(s)
- Gulnaz T Javan
- Forensic Science Program, Physical Sciences Department, Alabama State University, Montgomery, AL, USA.
| | - Erin Hanson
- National Center for Forensic Science, University of Central Florida, Orlando, FL, USA
| | - Sheree J Finley
- Forensic Science Program, Physical Sciences Department, Alabama State University, Montgomery, AL, USA
| | - Silvia D Visonà
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
| | - Antonio Osculati
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
| | - Jack Ballantyne
- National Center for Forensic Science, University of Central Florida, Orlando, FL, USA
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3
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Farnsworth B, Peuckert C, Zimmermann B, Jazin E, Kettunen P, Emilsson LS. Gene Expression of Quaking in Sporadic Alzheimer's Disease Patients is Both Upregulated and Related to Expression Levels of Genes Involved in Amyloid Plaque and Neurofibrillary Tangle Formation. J Alzheimers Dis 2018; 53:209-19. [PMID: 27163826 PMCID: PMC4942724 DOI: 10.3233/jad-160160] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Quaking (QKI) is a gene exclusively expressed within glial cells. QKI has previously been implicated in various neurological disorders and diseases, including Alzheimer’s disease (AD), a condition for which increasing evidence suggests a central role of glia cells. The objective of the present study was to investigate the expression levels of QKI and three QKI isoforms (QKI5, QKI6, and QKI7) in AD. Genes that have previously been related to the ontogeny and progression of AD, specifically APP, PSEN1, PSEN2, and MAPT, were also investigated. A real-time PCR assay of 123 samples from human postmortem sporadic AD patients and control brains was performed. The expression values were analyzed with an analysis of covariance model and subsequent multiple regressions to explore the possibility of related expression values between QKI, QKI isoforms, and AD-related genes. Further, the sequences of AD-related genes were analyzed for the presence of QKI binding domains. QKI and all measured QKI isoforms were found to be significantly upregulated in AD samples, relative to control samples. However, APP, PSEN1, PSEN2, and MAPT were not found to be significantly different. QKI and QKI isoforms were found to be predictive for the variance of APP, PSEN1, PSEN2, and MAPT, and putative QKI binding sites suggests an interaction with QKI. Overall, these results implicate a possible role of QKI in AD, although the exact mechanism by which this occurs remains to be uncovered.
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Affiliation(s)
- Bryn Farnsworth
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Christiane Peuckert
- Department of Neuroscience, Uppsala Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Bettina Zimmermann
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Elena Jazin
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Petronella Kettunen
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Neuropathology, Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Lina Sors Emilsson
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
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4
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Born JPL, Matos HDC, de Araujo MA, Castro OW, Duzzioni M, Peixoto-Santos JE, Leite JP, Garcia-Cairasco N, Paçó-Larson ML, Gitaí DLG. Using Postmortem hippocampi tissue can interfere with differential gene expression analysis of the epileptogenic process. PLoS One 2017; 12:e0182765. [PMID: 28783762 PMCID: PMC5544225 DOI: 10.1371/journal.pone.0182765] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 07/24/2017] [Indexed: 12/21/2022] Open
Abstract
Neuropathological studies often use autopsy brain tissue as controls to evaluate changes in protein or RNA levels in several diseases. In mesial temporal lobe epilepsy (MTLE), several genes are up or down regulated throughout the epileptogenic and chronic stages of the disease. Given that postmortem changes in several gene transcripts could impact the detection of changes in case-control studies, we evaluated the effect of using autopsy specimens with different postmortem intervals (PMI) on differential gene expression of the Pilocarpine (PILO)induced Status Epilepticus (SE) of MTLE. For this, we selected six genes (Gfap, Ppia, Gad65, Gad67, Npy, and Tnf-α) whose expression patterns in the hippocampus of PILO-injected rats are well known. Initially, we compared hippocampal expression of naïve rats whose hippocampi were harvested immediately after death (0h-PMI) with those harvested at 6h postmortem interval (6h-PMI): Npy and Ppia transcripts increased and Tnf-α transcripts decreased in the 6h-PMI group (p<0.05). We then investigated if these PMI-related changes in gene expression have the potential to adulterate or mask RT-qPCR results obtained with PILO-injected rats euthanized at acute or chronic phases. In the acute group, Npy transcript was significantly higher when compared with 0h-PMI rats, whereas Ppia transcript was lower than 6h-PMI group. When we used epileptic rats (chronic group), the RT-qPCR results showed higher Tnf-α only when compared to 6h-PMI group. In conclusion, our study demonstrates that PMI influences gene transcription and can mask changes in gene transcription seen during epileptogenesis in the PILO-SE model. Thus, to avoid erroneous conclusions, we strongly recommend that researchers account for changes in postmortem gene expression in their experimental design.
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Affiliation(s)
- João Paulo Lopes Born
- Department of Cellular and Molecular Biology, Institute of Biological Sciences and Health, Federal University of Alagoas, Maceio, Alagoas, Brazil
| | - Heloisa de Carvalho Matos
- Department of Cellular and Molecular Biology, Institute of Biological Sciences and Health, Federal University of Alagoas, Maceio, Alagoas, Brazil
| | - Mykaella Andrade de Araujo
- Department of Cellular and Molecular Biology, Institute of Biological Sciences and Health, Federal University of Alagoas, Maceio, Alagoas, Brazil
| | - Olagide Wagner Castro
- Department of Physiology and Pharmacology, Institute of Biological Sciences and Health, Federal University of Alagoas, Maceio, Alagoas, Brazil
| | - Marcelo Duzzioni
- Department of Physiology and Pharmacology, Institute of Biological Sciences and Health, Federal University of Alagoas, Maceio, Alagoas, Brazil
| | - José Eduardo Peixoto-Santos
- Division of Neurology, Department of Neurosciences and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - João Pereira Leite
- Division of Neurology, Department of Neurosciences and Behavioral Sciences, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Norberto Garcia-Cairasco
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Maria Luisa Paçó-Larson
- Department of Cellular and Molecular Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Daniel Leite Góes Gitaí
- Department of Cellular and Molecular Biology, Institute of Biological Sciences and Health, Federal University of Alagoas, Maceio, Alagoas, Brazil
- * E-mail:
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5
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Farnsworth B, Radomska KJ, Zimmermann B, Kettunen P, Jazin E, Emilsson LS. QKI6B mRNA levels are upregulated in schizophrenia and predict GFAP expression. Brain Res 2017; 1669:63-68. [PMID: 28552414 DOI: 10.1016/j.brainres.2017.05.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 05/21/2017] [Accepted: 05/22/2017] [Indexed: 01/21/2023]
Abstract
Schizophrenia is a highly heritable disorder with a heterogeneous symptomatology. Research increasingly indicates the importance of the crucial and often overlooked glial perturbations within schizophrenia. Within this study, we examined an isoform of quaking (a gene encoding an RNA-binding protein that is exclusively expressed in glial cells), known as QKI6B, and a prototypical astrocyte marker, glial fibrillary acidic protein (GFAP), postulated to be under the regulation of QKI. The expression levels of these genes were quantified across post-mortem brain samples from 55 schizophrenic individuals, and 55 healthy controls, using real-time PCR. We report, through an analysis of covariance (ANCOVA) model, an upregulation of both QKI6B, and GFAP in the prefrontal cortex of brain samples of schizophrenic individuals, as compared to control samples. Previous research has suggested that the QKI protein directly regulates the expression of several genes through interaction with a motif in the target's sequence, termed the Quaking Response Element (QRE). We therefore examined if QKI6B expression can predict the outcome of GFAP, and several oligodendrocyte-related genes, using a multiple linear regression approach. We found that QKI6B significantly predicts the expression of GFAP, but does not predict oligodendrocyte-related gene outcome, as previously seen with other QKI isoforms.
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Affiliation(s)
- B Farnsworth
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - K J Radomska
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - B Zimmermann
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - P Kettunen
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Neuropathology, Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - E Jazin
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - L S Emilsson
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
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6
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Kambhampati M, Perez JP, Yadavilli S, Saratsis AM, Hill AD, Ho CY, Panditharatna E, Markel M, Packer RJ, Nazarian J. A standardized autopsy procurement allows for the comprehensive study of DIPG biology. Oncotarget 2016; 6:12740-7. [PMID: 25749048 PMCID: PMC4494970 DOI: 10.18632/oncotarget.3374] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 01/15/2015] [Indexed: 11/25/2022] Open
Abstract
Diffuse intrinsic pontine glioma (DIPG) is one of the least understood and most deadly childhood cancers. Historically, there has been a paucity of DIPG specimens for molecular analysis. However, due to the generous participation of DIPG families in programs for postmortem specimen donation, there has been a recent surge in molecular analysis of newly available tumor specimens. Collaborative efforts to share data and tumor specimens have resulted in rapid discoveries in other pediatric brain tumors, such as medulloblastoma, and therefore have the potential to shed light on the biology of DIPG. Given the generous gift of postmortem tissue donation from DIPG patients, there is a need for standardized postmortem specimen accrual to facilitate rapid and effective multi-institutional molecular studies. We developed and implemented an autopsy protocol for rapid procurement, documenting and storing these specimens. Sixteen autopsies were performed throughout the United States and Canada and processed using a standard protocol and inventory method, including specimen imaging, fixation, snap freezing, orthotopic injection, or preservation. This allowed for comparative clinical and biological studies of rare postmortem DIPG tissue specimens, generation of in vivo and in vitro models of DIPG, and detailed records to facilitate collaborative analysis.
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Affiliation(s)
- Madhuri Kambhampati
- Research Center for Genetic Medicine, Children's National Health System, Washington, DC, USA
| | - Jennifer P Perez
- Research Center for Genetic Medicine, Children's National Health System, Washington, DC, USA
| | - Sridevi Yadavilli
- Research Center for Genetic Medicine, Children's National Health System, Washington, DC, USA
| | - Amanda M Saratsis
- Research Center for Genetic Medicine, Children's National Health System, Washington, DC, USA.,Division of Pediatric Neurosurgery, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA.,Department of Neurological Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Ashley D Hill
- Division of Pathology, Children's National Health System, Washington, DC, USA
| | - Cheng-Ying Ho
- Division of Pathology, Children's National Health System, Washington, DC, USA
| | - Eshini Panditharatna
- Research Center for Genetic Medicine, Children's National Health System, Washington, DC, USA.,Institute for Biomedical Sciences, George Washington University, Washington, DC, USA
| | - Melissa Markel
- Department of Neuro Oncology, Riley hospital for Children, Indiana University Health, Indianapolis, IN, USA
| | - Roger J Packer
- Brain Tumor Institute, Center for Neuroscience and Behavioral Medicine, Children's National Health System, Washington, DC, USA
| | - Javad Nazarian
- Research Center for Genetic Medicine, Children's National Health System, Washington, DC, USA.,Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
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7
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Beach TG, Adler CH, Sue LI, Serrano G, Shill HA, Walker DG, Lue L, Roher AE, Dugger BN, Maarouf C, Birdsill AC, Intorcia A, Saxon-Labelle M, Pullen J, Scroggins A, Filon J, Scott S, Hoffman B, Garcia A, Caviness JN, Hentz JG, Driver-Dunckley E, Jacobson SA, Davis KJ, Belden CM, Long KE, Malek-Ahmadi M, Powell JJ, Gale LD, Nicholson LR, Caselli RJ, Woodruff BK, Rapscak SZ, Ahern GL, Shi J, Burke AD, Reiman EM, Sabbagh MN. Arizona Study of Aging and Neurodegenerative Disorders and Brain and Body Donation Program. Neuropathology 2015; 35:354-89. [PMID: 25619230 DOI: 10.1111/neup.12189] [Citation(s) in RCA: 303] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 11/11/2014] [Indexed: 12/13/2022]
Abstract
The Brain and Body Donation Program (BBDP) at Banner Sun Health Research Institute (http://www.brainandbodydonationprogram.org) started in 1987 with brain-only donations and currently has banked more than 1600 brains. More than 430 whole-body donations have been received since this service was commenced in 2005. The collective academic output of the BBDP is now described as the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). Most BBDP subjects are enrolled as cognitively normal volunteers residing in the retirement communities of metropolitan Phoenix, Arizona. Specific recruitment efforts are also directed at subjects with Alzheimer's disease, Parkinson's disease and cancer. The median age at death is 82. Subjects receive standardized general medical, neurological, neuropsychological and movement disorders assessments during life and more than 90% receive full pathological examinations by medically licensed pathologists after death. The Program has been funded through a combination of internal, federal and state of Arizona grants as well as user fees and pharmaceutical industry collaborations. Subsets of the Program are utilized by the US National Institute on Aging Arizona Alzheimer's Disease Core Center and the US National Institute of Neurological Disorders and Stroke National Brain and Tissue Resource for Parkinson's Disease and Related Disorders. Substantial funding has also been received from the Michael J. Fox Foundation for Parkinson's Research. The Program has made rapid autopsy a priority, with a 3.0-hour median post-mortem interval for the entire collection. The median RNA Integrity Number (RIN) for frozen brain and body tissue is 8.9 and 7.4, respectively. More than 2500 tissue requests have been served and currently about 200 are served annually. These requests have been made by more than 400 investigators located in 32 US states and 15 countries. Tissue from the BBDP has contributed to more than 350 publications and more than 200 grant-funded projects.
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Affiliation(s)
- Thomas G Beach
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Lucia I Sue
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Geidy Serrano
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Holly A Shill
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - LihFen Lue
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Alex E Roher
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Chera Maarouf
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Alex C Birdsill
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | | | - Joel Pullen
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Jessica Filon
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Sarah Scott
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Angelica Garcia
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | | | | | | | - Kathryn J Davis
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Kathy E Long
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | | | - Lisa D Gale
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | | | | | | | | | - Jiong Shi
- Barrow Neurological Institute, Phoenix, Arizona, USA
| | - Anna D Burke
- Banner Alzheimer Institute, Phoenix, Arizona, USA
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8
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McCullumsmith RE, Hammond JH, Shan D, Meador-Woodruff JH. Postmortem brain: an underutilized substrate for studying severe mental illness. Neuropsychopharmacology 2014; 39:65-87. [PMID: 24091486 PMCID: PMC3857666 DOI: 10.1038/npp.2013.239] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 07/30/2013] [Accepted: 08/02/2013] [Indexed: 02/08/2023]
Abstract
We propose that postmortem tissue is an underutilized substrate that may be used to translate genetic and/or preclinical studies, particularly for neuropsychiatric illnesses with complex etiologies. Postmortem brain tissues from subjects with schizophrenia have been extensively studied, and thus serve as a useful vehicle for illustrating the challenges associated with this biological substrate. Schizophrenia is likely caused by a combination of genetic risk and environmental factors that combine to create a disease phenotype that is typically not apparent until late adolescence. The complexity of this illness creates challenges for hypothesis testing aimed at understanding the pathophysiology of the illness, as postmortem brain tissues collected from individuals with schizophrenia reflect neuroplastic changes from a lifetime of severe mental illness, as well as treatment with antipsychotic medications. While there are significant challenges with studying postmortem brain, such as the postmortem interval, it confers a translational element that is difficult to recapitulate in animal models. On the other hand, data derived from animal models typically provide specific mechanistic and behavioral measures that cannot be generated using human subjects. Convergence of these two approaches has led to important insights for understanding molecular deficits and their causes in this illness. In this review, we discuss the problem of schizophrenia, review the common challenges related to postmortem studies, discuss the application of biochemical approaches to this substrate, and present examples of postmortem schizophrenia studies that illustrate the role of the postmortem approach for generating important new leads for understanding the pathophysiology of severe mental illness.
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Affiliation(s)
| | - John H Hammond
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama-Birmingham, Birmingham, AL, USA
| | - Dan Shan
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama-Birmingham, Birmingham, AL, USA
| | - James H Meador-Woodruff
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama-Birmingham, Birmingham, AL, USA
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9
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Song HJ, Choi YL, Kang SY, Chae JM. The Effect of Elapsed Time on the Quantity of mRNA in Skin: A Study to Evaluate the Potential Forensic Use of mRNA to Determine the Postmortem Interval. ACTA ACUST UNITED AC 2012. [DOI: 10.7580/koreanjlegmed.2012.36.2.151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Hye Jong Song
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yoon La Choi
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - So Young Kang
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jong Min Chae
- Department of Forensic Medicine, Kyungpook National University School of Medicine, Daegu, Korea
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10
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Font MA, Arboix A, Krupinski J. Angiogenesis, neurogenesis and neuroplasticity in ischemic stroke. Curr Cardiol Rev 2011; 6:238-44. [PMID: 21804783 PMCID: PMC2994116 DOI: 10.2174/157340310791658802] [Citation(s) in RCA: 153] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2010] [Revised: 04/10/2010] [Accepted: 05/25/2010] [Indexed: 01/10/2023] Open
Abstract
Only very little is know about the neurovascular niche after cardioembolic stroke. Three processes implicated in neurorepair: angiogenesis, neurogenesis and synaptic plasticity, would be naturally produced in adult brains, but also could be stimulated through endogen neurorepair phenomena. Angiogenesis stimulation generates new vessels with the aim to increase collateral circulation. Neurogenesis is controlled by intrinsic genetic mechanisms and growth factors but also ambiental factors are important. The leading process of the migrating neural progenitor cells (NPCs) is closely associated with blood vessels, suggesting that this interaction provides directional guidance to the NPCs. These findings suggest that blood vessels play an important role as a scaffold for NPCs migration toward the damaged brain region. DNA microarray technology and blood genomic profiling in human stroke provided tools to investigate the expression of thousands of genes. Critical comparison of gene expression profiles after stroke in humans with those in animal models should lead to a better understanding of the pathophysiology of brain ischaemia. Probably the most important part of early recovery after stroke is limited capacity of penumbra/infarct neurones to recover. It became more clear in the last years, that penumbra is not just passively dying over time but it is also actively recovering. This initial plasticity in majority contributes towards later neurogenesis, angiogenesis and final recovery. Penumbra is a principal target in acute phase of stroke. Thus, the origin of newly formed vessels and the pathogenic role of neovascularization and neurogenesis are important unresolved issues in our understanding of the mechanisms after stroke. Biomaterials for promoting brain protection, repair and regeneration are new hot target. Recently developed biomaterials can enable and increase the target delivery of drugs or therapeutic proteins to the brain, allow cell or tissue transplants to be effectively delivered to the brain and help to rebuild damaged circuits. These new approaches are gaining clear importance because nanotechnology allows better control over material-cell interactions that induce specific developmental processes and cellular responses including differentiation, migration and outgrowth.
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11
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McCullumsmith RE, Meador-Woodruff JH. Novel approaches to the study of postmortem brain in psychiatric illness: old limitations and new challenges. Biol Psychiatry 2011; 69:127-33. [PMID: 21094488 DOI: 10.1016/j.biopsych.2010.09.035] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Revised: 09/14/2010] [Accepted: 09/27/2010] [Indexed: 11/29/2022]
Abstract
Biological psychiatry has made significant advances through the development of postmortem studies, animal models, and studies with living humans. Although these approaches each have advantages and disadvantages, the postmortem field is undergoing a significant shift toward more complex and informative methodologies. In the first part of this review, we summarize the long-standing methodologic challenges facing this field. In the second part of the article, we discuss the innovative approaches being used for postmortem studies, including laser capture microdissection and subcellular fractionization. These techniques will permit scientists working in the postmortem field to ask and answer the largest possible questions, providing new targets for drug discovery and improved treatments for severe mental illness.
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Affiliation(s)
- Robert E McCullumsmith
- Department of Psychiatry and Behavioral Neurobiology, Universityof Alabama at Birmingham School of Medicine, Birmingham, Alabama 35294, USA.
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12
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Caudle WM, Bammler TK, Lin Y, Pan S, Zhang J. Using 'omics' to define pathogenesis and biomarkers of Parkinson's disease. Expert Rev Neurother 2010; 10:925-42. [PMID: 20518609 DOI: 10.1586/ern.10.54] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Although great effort has been put forth to uncover the complex molecular mechanisms exploited in the pathogenesis of Parkinson's disease, a satisfactory explanation remains to be discovered. The emergence of several -omics techniques, transcriptomics, proteomics and metabolomics, have been integral in confirming previously identified pathways that are associated with dopaminergic neurodegeneration and subsequently Parkinson's disease, including mitochondrial and proteasomal function and synaptic neurotransmission. Additionally, these unbiased techniques, particularly in the brain regions uniquely associated with the disease, have greatly enhanced our ability to identify novel pathways, such as axon-guidance, that are potentially involved in Parkinson's pathogenesis. A comprehensive appraisal of the results obtained by different -omics has also reconfirmed the increase in oxidative stress as a common pathway likely to be critical in Parkinson's development/progression. It is hoped that further integration of these techniques will yield a more comprehensive understanding of Parkinson's disease etiology and the biological pathways that mediate neurodegeneration.
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Birdsill AC, Walker DG, Lue L, Sue LI, Beach TG. Postmortem interval effect on RNA and gene expression in human brain tissue. Cell Tissue Bank 2010; 12:311-8. [PMID: 20703815 DOI: 10.1007/s10561-010-9210-8] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Accepted: 07/22/2010] [Indexed: 11/29/2022]
Abstract
Banked tissue is essential to the study of neurological disease but using postmortem tissue introduces a number of possible confounds. Foremost amongst these are factors relating to variation in postmortem interval (PMI). Currently there are conflicting reports on how PMI affects overall RNA integrity, and very few reports of how gene expression is affected by PMI. We analyzed total RNA extracted from frozen cerebellar cortex from 79 deceased human subjects enrolled in the Banner Sun Health Research Institute Brain and Body Donation Program. The PMI, which ranged from 1.5 to 45 h, correlated with overall RNA quality measures including RNA Integrity Number (RIN) (r = -0.34, P = 0.002) and RNA quantitative yield (r = -0.25, P = 0.02). Additionally, we determined the expression of 89 genes using a PCR-based gene expression array (RT(2) Profiler™ PCR Array: Human Alzheimer's Disease; SABiosciences™, Frederick, MD). A greater proportion of genes had decreased rather than increased expression with increasing PMI (65/89 vs. 20/89; P < 0.0001). Of these, transcripts from the genes ADAM9, LPL, PRKCG, and SERPINA3 had significantly decreased expression with increasing PMI (P < 0.01). No individual gene transcripts had significantly increased expression with increasing PMI. In conclusion, it is apparent that RNA degrades progressively with increasing PMI and that measurement of gene expression in brain tissue with longer PMI may give artificially low values. For tissue derived from autopsy, a short PMI optimizes its utility for molecular research.
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Affiliation(s)
- Alex C Birdsill
- Civin Laboratory for Neuropathology, Brain and Body Donation Program, Banner Sun Health Research Institute, 10515 West Santa Fe Drive, Sun City, AZ 85351, USA
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Magold AI, Cacquevel M, Fraering PC. Gene expression profiling in cells with enhanced gamma-secretase activity. PLoS One 2009; 4:e6952. [PMID: 19763259 PMCID: PMC2739295 DOI: 10.1371/journal.pone.0006952] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Accepted: 07/27/2009] [Indexed: 01/10/2023] Open
Abstract
Background Processing by γ-secretase of many type-I membrane protein substrates triggers signaling cascades by releasing intracellular domains (ICDs) that, following nuclear translocation, modulate the transcription of different genes regulating a diverse array of cellular and biological processes. Because the list of γ-secretase substrates is growing quickly and this enzyme is a cancer and Alzheimer's disease therapeutic target, the mapping of γ-secretase activity susceptible gene transcription is important for sharpening our view of specific affected genes, molecular functions and biological pathways. Methodology/Principal Findings To identify genes and molecular functions transcriptionally affected by γ-secretase activity, the cellular transcriptomes of Chinese hamster ovary (CHO) cells with enhanced and inhibited γ-secretase activity were analyzed and compared by cDNA microarray. The functional clustering by FatiGO of the 1,981 identified genes revealed over- and under-represented groups with multiple activities and functions. Single genes with the most pronounced transcriptional susceptibility to γ-secretase activity were evaluated by real-time PCR. Among the 21 validated genes, the strikingly decreased transcription of PTPRG and AMN1 and increased transcription of UPP1 potentially support data on cell cycle disturbances relevant to cancer, stem cell and neurodegenerative diseases' research. The mapping of interactions of proteins encoded by the validated genes exclusively relied on evidence-based data and revealed broad effects on Wnt pathway members, including WNT3A and DVL3. Intriguingly, the transcription of TERA, a gene of unknown function, is affected by γ-secretase activity and was significantly altered in the analyzed human Alzheimer's disease brain cortices. Conclusions/Significance Investigating the effects of γ-secretase activity on gene transcription has revealed several affected clusters of molecular functions and, more specifically, 21 genes that hold significant potential for a better understanding of the biology of γ-secretase and its roles in cancer and Alzheimer's disease pathology.
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Affiliation(s)
- Alexandra I. Magold
- Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
| | - Matthias Cacquevel
- Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
| | - Patrick C. Fraering
- Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
- * E-mail:
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15
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Zhao D, Ishikawa T, Quan L, Michiue T, Zhu BL, Maeda H. Postmortem quantitative mRNA analyses of death investigation in forensic pathology: An overview and prospects. Leg Med (Tokyo) 2009; 11 Suppl 1:S43-5. [DOI: 10.1016/j.legalmed.2009.01.066] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Accepted: 01/08/2009] [Indexed: 11/27/2022]
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Jiang L, Saetre P, Jazin E, Carlström EL. Haloperidol changes mRNA expression of a QKI splice variant in human astrocytoma cells. BMC Pharmacol 2009; 9:6. [PMID: 19335891 PMCID: PMC2676266 DOI: 10.1186/1471-2210-9-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Accepted: 03/31/2009] [Indexed: 11/19/2022] Open
Abstract
Background The quaking homolog, KH domain RNA binding (mouse) (QKI) is a candidate gene for schizophrenia. Disturbed QKI mRNA expression is observed in the prefrontal cortex of patients, and some of these changes correlate to treatment with antipsychotic drugs. To test if low doses of antipsychotic drugs can modify QKI mRNA expression, human astrocytoma (U343) and oligodendroglioma (HOG) cell lines were treated with five different antipsychotic drugs including Haloperidol, Aripiprazole, Clozapine, Olanzapine and Risperidone. Messenger RNA expression levels of splice variants QKI-5, QKI-6 and QKI-7 were measured by Real-Time PCR. Results Haloperidol treatment (0.2 μM) doubled QKI-7 mRNA levels in U343 cells after 6 hours (p-value < 0.02). The effect was dose dependent, and cells treated with ten times higher concentration (2 μM) responded with a five-fold and three-fold increase in QKI-7, 6 and 24 hours after treatment, respectively (p-values < 0.0001). Conclusion The results in U343 cells suggest that QKI-7 mRNA expression in human astrocytes is induced by Haloperidol, at concentrations similar to plasma levels relevant to clinical treatment of schizophrenia. The molecular mechanism of action of antipsychotic drugs after binding to receptors is not well known. We hypothesize that QKI regulation is involved in this mechanism.
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Affiliation(s)
- Lin Jiang
- Department of Development and Genetics, Uppsala University, Sweden.
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Pazol K, Northcutt KV, Patisaul HB, Wallen K, Wilson ME. Progesterone and medroxyprogesterone acetate differentially regulate alpha4 subunit expression of GABA(A) receptors in the CA1 hippocampus of female rats. Physiol Behav 2009; 97:58-61. [PMID: 19394921 DOI: 10.1016/j.physbeh.2009.01.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Revised: 12/22/2008] [Accepted: 01/30/2009] [Indexed: 11/29/2022]
Abstract
The Women's Health Initiative trials - in which more extreme adverse outcomes were observed in the medroxyprogesterone acetate (MPA) + conjugated equine estrogen (CEE) arm, as compared to the CEE only arm - suggest that the addition of MPA to estrogen treatment has undesirable consequences. An important question raised by these results is whether the adverse outcomes observed in the progestin arm can be attributed to effects that are unique to MPA or are common to all progestins. In this study we explored the potential for MPA and progesterone (P4) to differentially impact neuroendocrine function by comparing their effects on mRNA expression for the alpha4 subunit of GABA(a) receptors in the CA1 hippocampus of female rats. Prior research has shown that P4, acting through its reduced metabolite allopregnanolone (AP), can mediate alpha4 subunit expression, thereby altering GABA(A) receptor gated currents. By contrast, MPA competitively inhibits the enzymes necessary for the synthesis of AP. In this study, ovariectomized females were primed with estradiol benzoate and then treated with P4, MPA, or vehicle. Subjects were sacrificed 12 h or 24 h later and in situ hybridization was used to measure alpha4 mRNA in the CA1 hippocampus. At 12 h but not 24 h, alpha4 mRNA was reduced in the P4 group as compared to the MPA group, and as compared to the vehicle group. These results suggest that MPA, while progestational in terms of its effects in the uterus, is not a simple substitute for P4 in other systems. The relative impact of these two progestins on neuroendocrine function must be carefully explored.
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Affiliation(s)
- Karen Pazol
- Emory University School of Medicine, 1462 Clifton Road, Suite 446, Atlanta GA 30322, United States.
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Reinius B, Saetre P, Leonard JA, Blekhman R, Merino-Martinez R, Gilad Y, Jazin E. An evolutionarily conserved sexual signature in the primate brain. PLoS Genet 2008; 4:e1000100. [PMID: 18566661 PMCID: PMC2413013 DOI: 10.1371/journal.pgen.1000100] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Accepted: 05/16/2008] [Indexed: 11/19/2022] Open
Abstract
The question of a potential biological sexual signature in the human brain is a heavily disputed subject. In order to provide further insight into this issue, we used an evolutionary approach to identify genes with sex differences in brain expression level among primates. We reasoned that expression patterns important to uphold key male and female characteristics may be conserved during evolution. We selected cortex for our studies because this specific brain region is responsible for many higher behavioral functions. We compared gene expression profiles in the occipital cortex of male and female humans (Homo sapiens, a great ape) and cynomolgus macaques (Macaca fascicularis, an old world monkey), two catarrhine species that show abundant morphological sexual dimorphism, as well as in common marmosets (Callithrix Jacchus, a new world monkey) which are relatively sexually monomorphic. We identified hundreds of genes with sex-biased expression patterns in humans and macaques, while fewer than ten were differentially expressed between the sexes in marmosets. In primates, a general rule is that many of the morphological and behavioral sexual dimorphisms seen in polygamous species, such as macaques, are typically less pronounced in monogamous species such as the marmosets. Our observations suggest that this correlation may also be reflected in the extent of sex-biased gene expression in the brain. We identified 85 genes with common sex-biased expression, in both human and macaque and 2 genes, X inactivation-specific transcript (XIST) and Heat shock factor binding protein 1 (HSBP1), that were consistently sex-biased in the female direction in human, macaque, and marmoset. These observations imply a conserved signature of sexual gene expression dimorphism in cortex of primates. Further, we found that the coding region of female-biased genes is more evolutionarily constrained compared to the coding region of both male-biased and non sex-biased brain expressed genes. We found genes with conserved sexual gene expression dimorphism in the occipital cortex of humans, cynomolgus macaques, and common marmosets. Genes within sexual expression profiles may underlie important functional differences between the sexes, with possible importance during primate evolution. The contribution of genetics versus environment to behavioral differences between the sexes is a fundamental question in neuroscience. We hypothesized that some differences between the sexes might be partially explained by sexually dependent gene expression differences in the brain. We further speculated that if differences in gene expression between males and females are functionally important, they may be conserved in the evolution of primates. To test these hypotheses, we measured gene expression in the brains of male and female primates from three species: humans (Homo sapiens), macaques (Macaca fascicularis), and marmosets (Callithrix jacchus). Our results point to a conserved signature of sexual gene expression dimorphism in the brains of primates. Interestingly, we found that genes with conserved sexual gene expression dimorphism in the brain also evolve under more evolutionary constraint, compared with other genes, suggesting that they may have important roles during evolution of sex in primates. Moreover, we found higher evolutionary constrains in the coding regions of female-biased genes as compared to both male-biased and non sex-biased brain expressed genes. The study of sex dimorphic genes may in the future shed light on the basis of psychiatric diseases with differences in prevalence between the sexes.
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Affiliation(s)
- Björn Reinius
- Department of Development and Genetics, Uppsala University, Uppsala, Sweden
| | - Peter Saetre
- Department of Development and Genetics, Uppsala University, Uppsala, Sweden
- Department of Clinical Neuroscience, HUBIN Project, Karolinska Institutet and Hospital, Stockholm, Sweden
| | | | - Ran Blekhman
- Department of Human Genetics, University of Chicago, Chicago, Illinois, United States of America
| | - Roxana Merino-Martinez
- Department of Molecular Medicine and Surgery, Karolinska Institutet and Hospital, Stockholm, Sweden
| | - Yoav Gilad
- Department of Human Genetics, University of Chicago, Chicago, Illinois, United States of America
| | - Elena Jazin
- Department of Development and Genetics, Uppsala University, Uppsala, Sweden
- * E-mail:
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Klee EW. Data Mining for Biomarker Development: A Review of Tissue Specificity Analysis. Clin Lab Med 2008; 28:127-43, viii. [DOI: 10.1016/j.cll.2007.10.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Papapetropoulos S, Shehadeh L, McCorquodale D. Optimizing human post-mortem brain tissue gene expression profiling in Parkinson's disease and other neurodegenerative disorders: from target "fishing" to translational breakthroughs. J Neurosci Res 2008; 85:3013-24. [PMID: 17503538 DOI: 10.1002/jnr.21355] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Insights on the etiopathogenesis of common neurodegenerative disorders such as Parkinson's disease (PD) and Alzheimer's disease (AD) have been largely based on the discovery of gene mutations in genetically determined forms. Although these discoveries have been helpful in elucidating the basic molecular pathogenesis of familial forms, they represent a small fraction of cases, leaving the large majority classified as idiopathic. In the postgenomic era, brain tissue gene expression profiling has allowed relative quantitative assessment of thousands of genes simultaneously from one tissue sample, providing clues for novel candidate genes and processes implicated in neurodegenerative disorders. Some remain critical of "fishing expedition" science, but gene expression profiling is a discovery-based procedure well suited for the study of largely idiopathic and multifactorial diseases. However, the technology is still under development, and many methodological and biological aspects contribute to the heterogeneous results obtained from gene expression profiling. In this Review, we discuss the advantages and limitations of this technology in simple terms and identify the key variables that influence/limit gene expression profiling-derived translational breakthroughs in neurodegenerative diseases.
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Affiliation(s)
- Spiridon Papapetropoulos
- Department of Neurology, University of Miami Miller School of Medicine, Miami, Florida 33136, USA.
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A microarray study of gene and protein regulation in human and rat brain following middle cerebral artery occlusion. BMC Neurosci 2007; 8:93. [PMID: 17997827 PMCID: PMC2194693 DOI: 10.1186/1471-2202-8-93] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Accepted: 11/12/2007] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Altered gene expression is an important feature of ischemic cerebral injury and affects proteins of many functional classes. We have used microarrays to investigate the changes in gene expression at various times after middle cerebral artery occlusion in human and rat brain. RESULTS Our results demonstrated a significant difference in the number of genes affected and the time-course of expression between the two cases. The total number of deregulated genes in the rat was 335 versus 126 in the human, while, of 393 overlapping genes between the two array sets, 184 were changed only in the rat and 36 in the human with a total of 41 genes deregulated in both cases. Interestingly, the mean fold changes were much higher in the human. The expression of novel genes, including p21-activated kinase 1 (PAK1), matrix metalloproteinase 11 (MMP11) and integrase interactor 1, was further analyzed by RT-PCR, Western blotting and immunohistochemistry. Strong neuronal staining was seen for PAK1 and MMP11. CONCLUSION Our findings confirmed previous studies reporting that gene expression screening can detect known and unknown transcriptional features of stroke and highlight the importance of research using human brain tissue in the search for novel therapeutic agents.
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22
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Saetre P, Emilsson L, Axelsson E, Kreuger J, Lindholm E, Jazin E. Inflammation-related genes up-regulated in schizophrenia brains. BMC Psychiatry 2007; 7:46. [PMID: 17822540 PMCID: PMC2080573 DOI: 10.1186/1471-244x-7-46] [Citation(s) in RCA: 211] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Accepted: 09/06/2007] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Multiple studies have shown that brain gene expression is disturbed in subjects suffering from schizophrenia. However, disentangling disease effects from alterations caused by medication is a challenging task. The main goal of this study is to find transcriptional alterations in schizophrenia that are independent of neuroleptic treatment. METHODS We compared the transcriptional profiles in brain autopsy samples from 55 control individuals with that from 55 schizophrenic subjects, subdivided according to the type of antipsychotic medication received. RESULTS Using global and high-resolution mRNA quantification techniques, we show that genes involved in immune response (GO:0006955) are up regulated in all groups of patients, including those not treated at the time of death. In particular, IFITM2, IFITM3, SERPINA3, and GBP1 showed increased mRNA levels in schizophrenia (p-values from qPCR < or = 0.01). These four genes were co-expressed in both schizophrenic subjects and controls. In-vitro experiments suggest that these genes are expressed in both oligodendrocyte and endothelial cells, where transcription is inducible by the inflammatory cytokines TNF-alpha, IFN-alpha and IFN-gamma. CONCLUSION Although the modified genes are not classical indicators of chronic or acute inflammation, our results indicate alterations of inflammation-related pathways in schizophrenia. In addition, the observation in oligodendrocyte cells suggests that alterations in inflammatory-related genes may have consequences for myelination. Our findings encourage future research to explore whether anti-inflammatory agents can be used in combination with traditional antipsychotics for a more efficient treatment of schizophrenia.
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Affiliation(s)
- Peter Saetre
- Department of Development and Genetics, Uppsala University, Sweden
| | - Lina Emilsson
- Department of Genetics and Pathology, Uppsala University, Rudbeck Laboratory, Sweden
| | - Elin Axelsson
- Department of Development and Genetics, Uppsala University, Sweden
| | - Johan Kreuger
- Department of Genetics and Pathology, Uppsala University, Rudbeck Laboratory, Sweden
| | - Eva Lindholm
- Department of Development and Genetics, Uppsala University, Sweden
| | - Elena Jazin
- Department of Development and Genetics, Uppsala University, Sweden
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Seppänen A, Suuronen T, Hofmann SC, Majamaa K, Alafuzoff I. Distribution of collagen XVII in the human brain. Brain Res 2007; 1158:50-6. [PMID: 17555727 DOI: 10.1016/j.brainres.2007.04.073] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2007] [Revised: 04/19/2007] [Accepted: 04/20/2007] [Indexed: 01/09/2023]
Abstract
We have recently discovered collagen XVII to be present in neurons of the human central nervous system. Collagen XVII has previously been primarily studied in the field of dermatopathology since it is abundantly expressed in the skin, which, like the nervous system, is ectodermal in origin. A link between dermatopathological and neurological entities has been implied due to clinical case studies revealing an association between bullous pemphigoid and age-related neurodegenerative disorders. The objective of this study was to assess the distribution of collagen XVII in the human brain in relation to normal ageing. Post-mortem brain tissue was obtained from 11 neurologically unimpaired subjects who had died from cardiovascular causes at the age of 17 to 78 years. Collagen XVII expression in various neuroanatomical regions, representing essentially the entire human brain, was then assessed using immunohistochemistry. We found collagen XVII to be expressed widely in the brain and to be located primarily in the soma and proximal axons of neurons. In contrast, glial cells did not express collagen XVII. The expression varied strikingly between different neuroanatomical regions, being most notable in motor nuclei and Betz cells followed by pyramidal neurons. There was no correlation between collagen XVII expression and variables such as gender, age at death, post-mortem delay and fixation time whereas a mode of death leading to notable neuronal ischemia depleted the protein expression. Many neurodegenerative disorders display a specific pattern of neuroanatomical involvement, thus the regionally variable expression of collagen XVII offers new prospects for research.
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Affiliation(s)
- Allan Seppänen
- Department of Clinical Medicine, Neurology, University of Kuopio, Finland
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Reduced expression of TAC1, PENK and SOCS2 in Hcrtr-2 mutated narcoleptic dog brain. BMC Neurosci 2007; 8:34. [PMID: 17521418 PMCID: PMC1885801 DOI: 10.1186/1471-2202-8-34] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Accepted: 05/23/2007] [Indexed: 11/18/2022] Open
Abstract
Background Narcolepsy causes dramatic behavioral alterations in both humans and dogs, with excessive sleepiness and cataplexy triggered by emotional stimuli. Deficiencies in the hypocretin system are well established as the origin of the condition; both from studies in humans who lack the hypocretin ligand (HCRT) and in dogs with a mutation in hypocretin receptor 2 (HCRTR2). However, little is known about molecular alterations downstream of the hypocretin signals. Results By using microarray technology we have screened the expression of 29760 genes in the brains of Doberman dogs with a heritable form of narcolepsy (homozygous for the canarc-1 [HCRTR-2-2] mutation), and their unaffected heterozygous siblings. We identified two neuropeptide precursor molecules, Tachykinin precursor 1 (TAC1) and Proenkephalin (PENK), that together with Suppressor of cytokine signaling 2 (SOCS2), showed reduced expression in narcoleptic brains. The difference was particularly pronounced in the amygdala, where mRNA levels of PENK were 6.2 fold lower in narcoleptic dogs than in heterozygous siblings, and TAC1 and SOCS2 showed 4.4 fold and 2.8 fold decrease in expression, respectively. The results obtained from microarray experiments were confirmed by real-time RT-PCR. Interestingly, it was previously shown that a single dose of amphetamine-like stimulants able to increase wakefulness in the dogs, also produce an increase in the expression of both TAC1 and PENK in mice. Conclusion These results suggest that TAC1, PENK and SOCS2 might be intimately connected with the excessive daytime sleepiness not only in dogs, but also in other species, possibly including humans.
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Stan AD, Ghose S, Gao XM, Roberts RC, Lewis-Amezcua K, Hatanpaa KJ, Tamminga CA. Human postmortem tissue: what quality markers matter? Brain Res 2006; 1123:1-11. [PMID: 17045977 PMCID: PMC1995236 DOI: 10.1016/j.brainres.2006.09.025] [Citation(s) in RCA: 291] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Revised: 09/07/2006] [Accepted: 09/08/2006] [Indexed: 11/30/2022]
Abstract
Postmortem human brain tissue is used for the study of many different brain diseases. A key factor in conducting postmortem research is the quality of the tissue. Unlike animal tissue, whose condition at death can be controlled and influenced, human tissue can only be collected naturalistically. This introduces potential confounds, based both on pre- and postmortem conditions, that may influence the quality of tissue and its ability to yield accurate results. The traditionally recognized confounds that reduce tissue quality are agonal factors (e.g., coma, hypoxia, hyperpyrexia at the time of death), and long postmortem interval (PMI). We measured tissue quality parameters in over 100 postmortem cases collected from different sources and correlated them with RNA quality (as indicated by the RNA Integrity Number (RIN)) and with protein quality (as measured by the level of representative proteins). Our results show that the most sensible indicator of tissue quality is RIN and that there is a good correlation between RIN and the pH. No correlation developed between protein levels and the aforementioned factors. Moreover, even when RNA was degraded, the protein levels remained stable. However, these correlations did not prove true under all circumstances (e.g., thawed tissue, surgical tissue), that yielded unexpected quality indicators. These data also suggest that cases whose source was a Medical Examiner's office represent high tissue quality.
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Affiliation(s)
- Ana D. Stan
- University of Texas Southwestern Medical Center at Dallas, Department of Psychiatry
| | - Subroto Ghose
- University of Texas Southwestern Medical Center at Dallas, Department of Psychiatry
| | - Xue-Min Gao
- University of Texas Southwestern Medical Center at Dallas, Department of Psychiatry
| | | | - Kelly Lewis-Amezcua
- University of Texas Southwestern Medical Center at Dallas, Department of Psychiatry
| | - Kimmo J. Hatanpaa
- University of Texas Southwestern Medical Center at Dallas, Department of Pathology
| | - Carol A. Tamminga
- University of Texas Southwestern Medical Center at Dallas, Department of Psychiatry
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Park YS, Chu HS, Hwang SH, Seo JH, Choi CY, Jung GY. A precise mRNA quantification method using CE-based SSCP. Electrophoresis 2006; 27:3836-45. [PMID: 16960841 DOI: 10.1002/elps.200600225] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Even though mRNA quantification provides significant information for biological analysis, current methods such as Northern blot analysis and real-time PCR are known to be laborious and lacking in precision. In this study, we demonstrate a new precise mRNA quantification method using CE based on SSCP (CE-SSCP) coupled with reverse transcription. mRNA samples could be simply analyzed for the quantification directly with reverse transcript obtained from a single reaction. This helps to avoid considerable errors generated by a series of the tedious manual steps. Also, unlike real-time PCR, reverse transcripts can be directly quantified by CE-SSCP in this method without further data estimation. Reproducibility and accuracy of CE-SSCP for mRNA quantification was examined using enhanced green fluorescent protein (eGFP) mRNA transcribed in vitro. Specific reverse transcription primer was determined for the accurate quantification of eGFP mRNA from total RNA obtained from the recombinant Escherichia coli. Using elongation factor Tu mRNA as an internal standard, it was shown that sample-to-sample variation could be minimized. Expression kinetics at both mRNA level and protein level was studied and the potential of CE-SSCP in expression analysis was demonstrated by comparison with the eGFP activity assay.
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Affiliation(s)
- Young Seoub Park
- Department of Chemical Engineering, POSTECH, Hyoja-dong, Pohang, Gyeongbuk, Korea
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Åberg K, Saetre P, Jareborg N, Jazin E. Human QKI, a potential regulator of mRNA expression of human oligodendrocyte-related genes involved in schizophrenia. Proc Natl Acad Sci U S A 2006; 103:7482-7. [PMID: 16641098 PMCID: PMC1464365 DOI: 10.1073/pnas.0601213103] [Citation(s) in RCA: 158] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The quaking viable mouse mutation (qk(v)) is a deletion including the 5' regulatory region of the quaking gene (Qki), which causes body tremor and severe dysmyelination in mouse. The function of the human quaking gene, called quaking homolog KH domain RNA-binding (mouse) (QKI), is not well known. We have previously shown that QKI is a new candidate gene for schizophrenia. Here we show that human QKI mRNA levels can account for a high proportion (47%) of normal interindividual mRNA expression variation (and covariation) of six oligodendrocyte-related genes (PLP1, MAG, MBP, TF, SOX10, and CDKN1B) in 55 human brain autopsy samples from individuals without psychiatric diagnoses. In addition, the tightly coexpressed myelin-related genes (PLP1, MAG, and TF) have decreased mRNA levels in 55 schizophrenic patients, as compared with 55 control individuals, and most of this difference (68-96%) can be explained by variation in the relative mRNA levels of QKI-7kb, the same QKI splice variant previously shown to be down-regulated in patients with schizophrenia. Taken together, our results suggest that QKI levels may regulate oligodendrocyte differentiation and maturation in human brain, in a similar way as in mouse. Moreover, we hypothesize that previously observed decreased activity of myelin-related genes in schizophrenia might be caused by disturbed QKI splicing.
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Affiliation(s)
- Karolina Åberg
- Departments of *Evolution, Genomics and Systematics, and
| | - Peter Saetre
- Development and Genetics, Uppsala University, SE-75236 Uppsala, Sweden; and
| | | | - Elena Jazin
- Development and Genetics, Uppsala University, SE-75236 Uppsala, Sweden; and
- To whom correspondence should be addressed. E-mail:
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Emilsson L, Saetre P, Jazin E. Low mRNA levels of RGS4 splice variants in Alzheimer's disease: association between a rare haplotype and decreased mRNA expression. Synapse 2006; 59:173-6. [PMID: 16358332 DOI: 10.1002/syn.20226] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Regulator of G-protein signaling 4 (RGS4) showed decreased mRNA levels in Alzheimer's disease in a large collection of human brain autopsies from prefrontal cortex. The expression levels of three RGS4 splice variants were examined in the same samples, and the association between RGS4 gene expression and/or the disease with single nucleotide polymorphisms located in this gene was explored. We show that all splice variants are down-regulated in patients. We also demonstrate that one rare haplotype (ATAG) is associated with decreased mRNA levels in both cases and controls. Our results suggest that an altered regulation in transcription initiation may be an important mechanism for low RGS4 protein levels in Alzeimer's disease.
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Affiliation(s)
- L Emilsson
- Department of Evolution, Genomics and Systematics, Uppsala University, Norbyvagen 18D, 75236 Uppsala, Sweden
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29
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Zhao D, Zhu BL, Ishikawa T, Quan L, Li DR, Maeda H. Real-time RT-PCR quantitative assays and postmortem degradation profiles of erythropoietin, vascular endothelial growth factor and hypoxia-inducible factor 1 alpha mRNA transcripts in forensic autopsy materials. Leg Med (Tokyo) 2006; 8:132-6. [PMID: 16337823 DOI: 10.1016/j.legalmed.2005.09.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Revised: 09/12/2005] [Accepted: 09/28/2005] [Indexed: 10/25/2022]
Abstract
Recent advances in molecular biology have suggested the potential usefulness of mRNA analyses in postmortem investigations of fatal mechanisms. The aim of the present study was to establish quantitative assays of oxygen-regulated factors including erythropoietin (EPO), vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1 alpha (HIF1A) mRNAs, and to investigate the postmortem stability of these mRNA transcripts in forensic autopsy materials. Relative quantification of EPO, VEGF and HIF1A mRNAs, based on the TaqMan reverse transcription-polymerase chain reaction (RT-PCR), was performed on autopsy tissue specimens from the heart (n = 10), brain (n = 10), kidney (n = 16) and lung (n = 8) after preservation at room temperature for various storage times. VEGF and HIF1A mRNA gradually degraded in patterns similar to glyceraldehydes-3-phosphate dehydrogenase (GAPDH) mRNA used as an endogenous reference. Accordingly, the relative quantification of VEGF/GAPDH and HIF1A/GAPDH changed little up to 48h postmortem in tissue samples from the brain, kidney and lung except for a mild deviation of HIF1A in the myocardium. However, the status was different for EPO mRNA, with extraordinary stability for postmortem degradation and a marked postmortem time-dependent increase in the EPO/GAPDH ratio for all tissue samples. The present study suggested the potential for applying quantitative analyses of mRNA transcripts to autopsy materials and indicated the significance of investigating degradation profiles prior to carrying out relative quantification of target mRNAs in autopsy materials.
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Affiliation(s)
- Dong Zhao
- Department of Legal Medicine, Osaka City University Medical School, Asahi-machi 1-4-3, Abeno, Osaka 545-8585, Japan.
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30
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Aberg K, Saetre P, Lindholm E, Ekholm B, Pettersson U, Adolfsson R, Jazin E. Human QKI, a new candidate gene for schizophrenia involved in myelination. Am J Med Genet B Neuropsychiatr Genet 2006; 141B:84-90. [PMID: 16342280 DOI: 10.1002/ajmg.b.30243] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We have previously shown that chromosome 6q25-6q27 includes a susceptibility locus for schizophrenia in a large pedigree from northern Sweden. In this study, we fine-mapped a 10.7 Mb region, included in this locus, using 42 microsatellites or SNP markers. We found a 0.5 Mb haplotype, likely to be inherited identical by decent, within the large family that is shared among the majority of the patients (69%). A gamete competition test of this haplotype in 176 unrelated nuclear families from the same geographical area as the large family showed association to schizophrenia (empirical P-value 0.041). The only gene located in the region, the quaking homolog, KH domain RNA binding (mouse) (QKI), was investigated in human brain autopsies from 55 cases and 55 controls using a high-resolution mRNA expression analysis. Relative mRNA expression levels of two QKI splice variants were clearly downregulated in schizophrenic patients (P-value 0.0004 and 0.03, respectively). The function of QKI has not been studied in humans, but the mouse homolog is involved in neural development and myelination. In conclusion, we present evidence from three unrelated sample-sets that propose the involvement of the QKI gene in schizophrenia. The two family based studies suggest that there may be functional variants of the QKI gene that increase the susceptibility of schizophrenia in northern Sweden, whereas the case-control study suggest that splicing of the gene may be disturbed in schizophrenic patients from other geographical origins. Taken together, we propose QKI as a possible target for functional studies related to the role of myelination in schizophrenia.
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Affiliation(s)
- Karolina Aberg
- Department of Evolution, Genomics and Systematics, Uppsala University, Norbyvägen 18D, 752-36 Uppsala, Sweden
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31
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Abstract
With the increasing application of genomic and proteomic technologies to the research of neurological and psychiatric disorders it has become imperative that the postmortem tissue utilized be of the highest quality possible. Every step of the research design, from identifying donors, acquiring sufficient information for accurate diagnosis, to assessing tissue quality has to be carefully considered. In order to obtain high-quality RNA and protein from the postmortem brain tissue a standardized system of brain collection, dissection, and storage must be employed and key ante- and postmortem factors must be considered. Reliable RNA expression and protein data can be obtained from postmortem brains with relatively long postmortem intervals (PMIs) if the agonal factors and acidosis are not severe. While pH values are correlated with RNA integrity number (RIN), a higher pH does not guarantee intact RNA. Consequently RNA integrity must be assessed for every case before it is included in a study. An analysis of anti- and postmortem factors in a large brain collection has revealed that several diagnostic groups have significantly lower pH values than other groups, however, they do not have significantly lower RIN values. Moreover, the lower pH of these groups is not entirely due to agonal factors and/or smoking, indicating that these subjects may have additional metabolic abnormalities that contribute to the lower pH values.
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32
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Franz H, Ullmann C, Becker A, Ryan M, Bahn S, Arendt T, Simon M, Pääbo S, Khaitovich P. Systematic analysis of gene expression in human brains before and after death. Genome Biol 2005; 6:R112. [PMID: 16420671 PMCID: PMC1414111 DOI: 10.1186/gb-2005-6-13-r112] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2005] [Revised: 08/23/2005] [Accepted: 12/06/2005] [Indexed: 12/02/2022] Open
Abstract
Comparison of the gene expression profiles of pre- and post-mortem human brains suggests that post-mortem human brain samples are suitable for investigating general gene-expression patterns. Background Numerous studies have employed microarray techniques to study changes in gene expression in connection with human disease, aging and evolution. The vast majority of human samples available for research are obtained from deceased individuals. This raises questions about how well gene expression patterns in such samples reflect those of living individuals. Results Here, we compare gene expression patterns in two human brain regions in postmortem samples and in material collected during surgical intervention. We find that death induces significant expression changes in more than 10% of all expressed genes. These changes are non-randomly distributed with respect to their function. Moreover, we observe similar expression changes due to death in two distinct brain regions. Consequently, the pattern of gene expression differences between the two brain regions is largely unaffected by death, although the magnitude of differences is reduced by 50% in postmortem samples. Furthermore, death-induced changes do not contribute significantly to gene expression variation among postmortem human brain samples. Conclusion We conclude that postmortem human brain samples are suitable for investigating gene expression patterns in humans, but that caution is warranted in interpreting results for individual genes.
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Affiliation(s)
- Henriette Franz
- Max-Planck-Institute for Evolutionary Anthropology, Deutscher Platz, D-04103 Leipzig, Germany
| | - Claudia Ullmann
- Department of Neuropathology and National Brain Tumor Reference Center, University of Bonn Medical Center, Sigmund-Freud-Strasse, D-53105 Bonn, Germany
| | - Albert Becker
- Department of Neuropathology and National Brain Tumor Reference Center, University of Bonn Medical Center, Sigmund-Freud-Strasse, D-53105 Bonn, Germany
| | - Margaret Ryan
- Cambridge Centre for Neuropsychiatric Research, Institute of Biotechnology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QT, UK
| | - Sabine Bahn
- Cambridge Centre for Neuropsychiatric Research, Institute of Biotechnology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QT, UK
| | - Thomas Arendt
- Paul Flechsig Institute for Brain Research, University of Leipzig, Jahnallee, D-04109 Leipzig, Germany
| | - Matthias Simon
- Department of Neurosurgery, University of Bonn Medical Center, Sigmund-Freud-Strasse, D-53105 Bonn, Germany
| | - Svante Pääbo
- Max-Planck-Institute for Evolutionary Anthropology, Deutscher Platz, D-04103 Leipzig, Germany
| | - Philipp Khaitovich
- Max-Planck-Institute for Evolutionary Anthropology, Deutscher Platz, D-04103 Leipzig, Germany
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Kannanayakal TJ, Eberwine J. mRNA methods used in dissecting gene expression of the brain. Ageing Res Rev 2005; 4:513-28. [PMID: 16257586 DOI: 10.1016/j.arr.2005.09.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2005] [Accepted: 09/07/2005] [Indexed: 10/25/2022]
Affiliation(s)
- Theresa Joseph Kannanayakal
- Department of Pharmacology, University of Pennsylvania School of Medicine, 37 John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA 19104-6084, USA
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34
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Lindberg J, Björnerfeldt S, Saetre P, Svartberg K, Seehuus B, Bakken M, Vilà C, Jazin E. Selection for tameness has changed brain gene expression in silver foxes. Curr Biol 2005; 15:R915-6. [PMID: 16303546 DOI: 10.1016/j.cub.2005.11.009] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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35
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Emilsson L, Saetre P, Jazin E. Alzheimer's disease: mRNA expression profiles of multiple patients show alterations of genes involved with calcium signaling. Neurobiol Dis 2005; 21:618-25. [PMID: 16257224 DOI: 10.1016/j.nbd.2005.09.004] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Revised: 08/23/2005] [Accepted: 09/12/2005] [Indexed: 11/24/2022] Open
Abstract
We combined global and high-resolution strategies to find genes with altered mRNA expression levels in one of the largest collection of brain autopsies from Alzheimer's patients and controls ever studied. Our global analysis involved microarray hybridizations of large pools of samples obtained from 114 individuals, using two independent sets of microarrays. Ten genes selected from the microarray experiments were quantified on each individual separately using real-time RT-PCR. This high-resolution analysis accounted for systematic differences in age, postmortem interval, brain pH, and reference gene expression, and it estimated the effect of disease on mRNA levels, on top of the effect of all other variables. Differential expression was confirmed for eight out of ten genes. Among them, Type B inositol 1,4,5-trisphosphate 3-kinase (ITPKB), and regulator of G protein signaling 4 (RGS4) showed highly altered expression levels in patients (P values < 0.0001). Our results point towards increased inositol triphospate (IP3)-mediated calcium signaling in Alzheimer's disease.
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Affiliation(s)
- L Emilsson
- Department of Evolution, Genomics and Systematics, Uppsala University, Norbyvagen 18D, 75236 Uppsala, Sweden
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36
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Castensson A, Aberg K, McCarthy S, Saetre P, Andersson B, Jazin E. Serotonin receptor 2C (HTR2C) and schizophrenia: examination of possible medication and genetic influences on expression levels. Am J Med Genet B Neuropsychiatr Genet 2005; 134B:84-9. [PMID: 15717293 DOI: 10.1002/ajmg.b.30151] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The serotonin receptor 2C (HTR2C) gene is of interest in schizophrenia due to its involvement in regulation of dopamine activity in the prefrontal cortex. We have previously reported a decreased expression of HTR2C mRNA levels in the prefrontal cortex of schizophrenia patients. The variability in mRNA expression levels is evaluated here more closely in relation to promoter haplotypes and neuroleptic treatment received by the patients. The decrease in HTR2C mRNA was present in neuroleptic treated individuals and in patients untreated at death, indicating that the lower expression is not a short-term medication effect. Three promoter polymorphisms were used to construct haplotypes. No SNP displayed genotypic or haplotypic association with the disease. Gene expression of HTR2C was not affected by haplotype and the expression decrease in schizophrenia patients was similar in all haplotype combinations (diplotypes). We conclude that the decrease in HTR2C expression in schizophrenia may be related to the disease mechanism rather than to drug treatment. The disease related changes in HTR2C expression are not related to the promoter variants typed in our sample, but could be due to other regulatory variants or trans-acting factors.
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Affiliation(s)
- Anja Castensson
- Department of Evolution, Genomics and Systematics, Evolutionary Biology Centre (EBC), Uppsala University, Uppsala, Sweden.
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37
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Katsel PL, Davis KL, Haroutunian V. Large-Scale Microarray Studies of Gene Expression in Multiple Regions of the Brain in Schizophrenia and Alzheimer's Disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2005; 63:41-82. [PMID: 15797465 DOI: 10.1016/s0074-7742(05)63003-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Pavel L Katsel
- Department of Psychiatry, The Mount Sinai School of Medicine New York, New York 10029 USA
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38
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Tromp G, Gatalica Z, Skunca M, Berguer R, Siegel T, Kline RA, Kuivaniemi H. Elevated expression of matrix metalloproteinase-13 in abdominal aortic aneurysms. Ann Vasc Surg 2004; 18:414-20. [PMID: 15156361 DOI: 10.1007/s10016-004-0050-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Destructive remodeling of extracellular matrix has been shown to be present in aneurysmal abdominal aorta. We used real-time quantitative reverse transcriptase polymerase chain reaction to determine the relative expression of matrix metalloproteinase-13 (MMP13) in aortic tissue samples from patients who underwent abdominal aortic aneurysm repair operations (n = 36) and from nonaneurysmal autopsy samples (n = 20). The assays were carried out simultaneously in the same reaction tubes for ribosomal 18S RNA to correct for different amounts of input RNA. MMP13 was expressed in all parts of aorta and its expression was elevated in aneurysmal sac. In further studies using MMP13-specific antibody we demonstrated that MMP13 protein was present in the aneurysmal wall.
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Affiliation(s)
- Gerard Tromp
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI 48201, USA
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39
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Saetre P, Lindberg J, Leonard JA, Olsson K, Pettersson U, Ellegren H, Bergström TF, Vilà C, Jazin E. From wild wolf to domestic dog: gene expression changes in the brain. ACTA ACUST UNITED AC 2004; 126:198-206. [PMID: 15249144 DOI: 10.1016/j.molbrainres.2004.05.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/05/2004] [Indexed: 10/26/2022]
Abstract
Despite the relatively recent divergence time between domestic dogs (Canis familiaris) and gray wolves (Canis lupus), the two species show remarkable behavioral differences. Since dogs and wolves are nearly identical at the level of DNA sequence, we hypothesize that the two species may differ in patterns of gene expression. We compare gene expression patterns in dogs, wolves and a close relative, the coyote (Canis latrans), in three parts of the brain: hypothalamus, amygdala and frontal cortex, with microarray technology. Additionally, we identify genes with region-specific expression patterns in all three species. Among the wild canids, the hypothalamus has a highly conserved expression profile. This contrasts with a marked divergence in domestic dogs. Real-time PCR experiments confirm the altered expression of two neuropeptides, CALCB and NPY. Our results suggest that strong selection on dogs for behavior during domestication may have resulted in modifications of mRNA expression patterns in a few hypothalamic genes with multiple functions. This study indicates that rapid changes in brain gene expression may not be exclusive to the development of human brains. Instead, they may provide a common mechanism for rapid adaptive changes during speciation, particularly in cases that present strong selective pressures on behavioral characters.
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Affiliation(s)
- Peter Saetre
- Department of Evolution, Genomics and Systematics, Uppsala University, Norbyvagen 18D, S-752 36 Uppsala, Sweden
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40
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Preece P, Virley DJ, Costandi M, Coombes R, Moss SJ, Mudge AW, Jazin E, Cairns NJ. Amyloid precursor protein mRNA levels in Alzheimer's disease brain. ACTA ACUST UNITED AC 2004; 122:1-9. [PMID: 14992810 DOI: 10.1016/j.molbrainres.2003.08.022] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2003] [Indexed: 01/02/2023]
Abstract
Insoluble beta-amyloid deposits in Alzheimer's disease (AD) brain are proteolytically derived from the membrane bound amyloid precursor protein (APP). The APP gene is differentially spliced to produce isoforms that can be classified into those containing a Kunitz-type serine protease inhibitor domain (K(+), APP(751), APP(770), APRP(365) and APRP(563)), and those without (K(-), APP(695) and APP(714)). Given the hypothesis that Abeta is a result of aberrant catabolism of APP, differential expression of mRNA isoforms containing protease inhibitors might play an active role in the pathology of AD. We took 513 cerebral cortex samples from 90 AD and 81 control brains and quantified the mRNA isoforms of APP with TaqMan real-time RT-PCR. After adjustment for age at death, brain pH and gender we found a change in the ratio of KPI(+) to KPI(-) mRNA isoforms of APP. Three separate probes, designed to recognise only KPI(+) mRNA species, gave increases of between 28% and 50% in AD brains relative to controls (p=0.002). There was no change in the mRNA levels of KPI-(APP 695) (p=0.898). Therefore, whilst KPI-mRNA levels remained stable the KPI(+) species increased specifically in the AD brains.
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Affiliation(s)
- Paul Preece
- Seixo Branco, Departamento de Neurologia, Rua das Brañas 7-bajo-D, Mera, 15177 Oleiros, La Coruña, Galicia, Spain.
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41
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Almeida A, Paul Thiery J, Magdelénat H, Radvanyi F. Gene expression analysis by real-time reverse transcription polymerase chain reaction: influence of tissue handling. Anal Biochem 2004; 328:101-8. [PMID: 15113684 DOI: 10.1016/j.ab.2004.02.004] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2003] [Indexed: 12/31/2022]
Abstract
Factors such as warm ischemia and time at room temperature before tissue treatment may influence the results of mRNA expression analyses on tissue specimens obtained during surgery. We evaluated the effect of these factors on RNA integrity and mRNA expression levels by incubating freshly obtained mouse liver tissue at 25 or 37 degrees C for periods of 0-4 h. Changes in the mRNA expression levels of seven genes, Tbp, Eef1a, Fos, Junb, Myc, Vegf, and Glut2, were determined by real-time reverse transcription-polymerase chain reaction. Incubation at 25 degrees C for up to 4 h only slightly altered (by a factor of less than 2) levels of mRNA for Tbp, Eef1a, Junb, Myc, Vegf, and Glut2. This result is consistent with limited RNA degradation at this temperature. Incubation at 37 degrees C strongly affected the levels of these mRNAs. Four hours of incubation at this temperature resulted in extensive RNA degradation, with mRNA levels falling to 1/10th those before incubation. When relative quantification was performed, i.e., quantification of the target gene transcripts in comparison to an endogenous housekeeping transcript (Tbp or Eef1a), the changes in mRNA levels were reduced to less than 2.5-fold. Fos behaved very differently from the other genes tested on incubation, with Fos mRNA levels increasing considerably following incubation at either 25 or 37 degrees C. Our data suggest that, with the exception of certain genes induced by tissue injury, relative quantification of mRNA, even on degraded RNA samples, can provide a reliable estimate of in vivo mRNA levels.
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Affiliation(s)
- Anna Almeida
- Laboratoire de Transfert, Institut Curie, 26 rue d'Ulm, 75248 Paris Cedex 05, France
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42
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Wilson KE, Ryan MM, Prime JE, Pashby DP, Orange PR, O'Beirne G, Whateley JG, Bahn S, Morris CM. Functional genomics and proteomics: application in neurosciences. J Neurol Neurosurg Psychiatry 2004; 75:529-38. [PMID: 15026490 PMCID: PMC1739030 DOI: 10.1136/jnnp.2003.026260] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The sequencing of the complete genome for many organisms, including man, has opened the door to the systematic understanding of how complex structures such as the brain integrate and function, not only in health but also in disease. This blueprint, however, means that the piecemeal analysis regimes of the past are being rapidly superseded by new methods that analyse not just tens of genes or proteins at any one time, but thousands, if not the entire repertoire of a cell population or tissue under investigation. Using the most appropriate method of analysis to maximise the available data therefore becomes vital if a complete picture is to be obtained of how a system or individual cell is affected by a treatment or disease. This review examines what methods are currently available for the large scale analysis of gene and protein expression, and what are their limitations.
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Affiliation(s)
- K E Wilson
- MRC Building, Newcastle General Hospital, Westgate Road, Newcastle upon Tyne, UK
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43
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Mimmack ML, Brooking J, Bahn S. Quantitative polymerase chain reaction: validation of microarray results from postmortem brain studies. Biol Psychiatry 2004; 55:337-45. [PMID: 14960285 DOI: 10.1016/j.biopsych.2003.09.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2003] [Revised: 09/09/2003] [Accepted: 09/17/2003] [Indexed: 11/23/2022]
Abstract
Quantitative polymerase chain reaction (Q-PCR) is now considered the "technique of choice" for validating gene expression changes identified with ribonucleic acid-based expression profiling technologies (especially micro- and macroarray techniques). The identification of altered gene expression profiles with microarrays is best viewed as the first step in the determination of potential disease-associated genes; however, the false-positive rate can be high, particularly with small sample sets and in view of the typically small differences observed in brain expression studies. Quantitative PCR is a rapid and highly sensitive technique for accurate quantification of microarray results; however, careful consideration of experimental design, quality of primer/probe design, internal standards, and normalization procedures are pivotal, particularly when the work involves postmortem tissue.
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Affiliation(s)
- Michael L Mimmack
- Department of Neurobiology, The Babraham Institute, Babraham, Cambridge CB2 4AT, United Kingdom
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44
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Becker J, Schmidt P, Musshoff F, Fitzenreiter M, Madea B. MOR1 receptor mRNA expression in human brains of drug-related fatalities—a real-time PCR quantification. Forensic Sci Int 2004; 140:13-20. [PMID: 15013161 DOI: 10.1016/j.forsciint.2003.10.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2002] [Accepted: 10/22/2003] [Indexed: 11/28/2022]
Abstract
The expression of the human micro-opiate receptor (MOR1) in post mortem human brain tissue was examined using real-time PCR technology. Tissue samples from 11 fatalities due to opiate overdose and five normal subjects with different causes of death were analysed in order to elucidate whether chronic opiate abuse is followed by a regulation of MOR1 expression. In each case nine selected brain regions (thalamus, caudate nucleus, hypothalamus, ventral tegmentum, hippocampus, amygdala, frontal cortex, nucleus accumbens, putamen) were evaluated. The MOR1-mRNA level was determined relative to the housekeeping gene beta2-microglobulin. While in most regions the MOR mRNA levels in the brain of addicts were not different from the control group-with varying levels between 0 and 15% of housekeeping gene level-in the brains of three drug-related fatalities an enormous increase was encountered in the thalamus where the MOR-mRNA level amounted for up to 10,000% of the measured housekeeping gene level. The results obtained by toxicological hair analysis in the group of drug-related fatalities indicate that the enormous thalamic MOR1-expression is primarily found in individuals who died from acute heroin overdose but did not show signs of a substantial chronic administration of the drug. Further studies have to be performed to evaluate if the observed MOR1-mRNA up-regulation in the thalamus in a subpopulation of acute lethal intoxications mirrors a state of functional hypersensitivity associated with the occurrence of death.
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Affiliation(s)
- J Becker
- Institute of Forensic Medicine, Friedrich-Wilhelms-University Bonn, Stiftsplatz 12, D-53111 Bonn, Germany
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45
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Li JZ, Vawter MP, Walsh DM, Tomita H, Evans SJ, Choudary PV, Lopez JF, Avelar A, Shokoohi V, Chung T, Mesarwi O, Jones EG, Watson SJ, Akil H, Bunney WE, Myers RM. Systematic changes in gene expression in postmortem human brains associated with tissue pH and terminal medical conditions. Hum Mol Genet 2004; 13:609-16. [PMID: 14734628 DOI: 10.1093/hmg/ddh065] [Citation(s) in RCA: 211] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Studies of gene expression abnormalities in psychiatric or neurological disorders often involve the use of postmortem brain tissue. Compared with single-cell organisms or clonal cell lines, the biological environment and medical history of human subjects cannot be controlled, and are often difficult to document fully. The chance of finding significant and replicable changes depends on the nature and magnitude of the observed variations among the studied subjects. During an analysis of gene expression changes in mood disorders, we observed a remarkable degree of natural variation among 120 samples, which represented three brain regions in 40 subjects. Most of such diversity can be accounted for by two distinct expression patterns, which in turn are strongly correlated with tissue pH. Individuals who suffered prolonged agonal states, such as with respiratory arrest, multi-organ failure or coma, tended to have lower pH in the brain; whereas those who experienced brief deaths, associated with accidents, cardiac events or asphyxia, generally had normal pH. The lower pH samples exhibited a systematic decrease in expression of genes involved in energy metabolism and proteolytic activities, and a consistent increase of genes encoding stress-response proteins and transcription factors. This functional specificity of changed genes suggests that the difference is not merely due to random RNA degradation in low pH samples; rather it reflects a broad and actively coordinated biological response in living cells. These findings shed light on critical molecular mechanisms that are engaged during different forms of terminal stress, and may suggest clinical targets of protection or restoration.
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Affiliation(s)
- Jun Z Li
- Department of Genetics, Stanford University School of Medicine, California 94305, USA
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Bauer M, Gramlich I, Polzin S, Patzelt D. Quantification of mRNA degradation as possible indicator of postmortem interval—a pilot study. Leg Med (Tokyo) 2003; 5:220-7. [PMID: 14602165 DOI: 10.1016/j.legalmed.2003.08.001] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Postmortem RNA degradation is a complex process which has not been studied systematically up to now. RNA, in contrast to DNA, is degraded in vivo to control translation and is believed to be less stable than DNA in vitro and postmortem due to ubiquitously present ribonucleases. Quantification of the fragmentation level of human mRNA might be a tool for determination for the time since death. We have developed a method for quantitating mRNA degradation by multiplex-RT-PCR coupled to laser-induced fluorescence capillary electrophoresis. The study included whole blood samples from living individuals and postmortem blood and brain samples which were stored refrigerated for up to 5 days. It could be shown that RNA degradation is significantly correlated with the storage interval of blood samples taken from living individuals and with the postmortem interval (PMI) in autopsy cases. This technique might become a parameter for the assessment of RNA quality in postmortem samples used for diagnosis and research and for the determination of the PMI. However, rather large confidence intervals have to be considered so that the use of this method in forensic casework requires further research.
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Affiliation(s)
- Martin Bauer
- Institute of Legal Medicine, University of Wuerzburg, Versbacher Strasse 3, D-97078 Wuerzburg, Germany.
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Castensson A, Emilsson L, Sundberg R, Jazin E. Decrease of serotonin receptor 2C in schizophrenia brains identified by high-resolution mRNA expression analysis. Biol Psychiatry 2003; 54:1212-21. [PMID: 14643089 DOI: 10.1016/s0006-3223(03)00526-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND RNA expression profiling can provide hints for the selection of candidate susceptibility genes, for formulation of hypotheses about the development of a disease, and/or for selection of candidate gene targets for novel drug development. We measured messenger RNA expression levels of 16 candidate genes in brain samples from 55 schizophrenia patients and 55 controls. This is the largest sample so far used to identify genes differentially expressed in schizophrenia brains. METHODS We used a sensitive real-time polymerase chain reaction methodology and a novel statistical approach, including the development of a linear model of analysis of covariance type. RESULTS We found two genes differentially expressed: monoamine oxidase B was significantly increased in schizophrenia brain (p =.001), whereas one of the serotonin receptor genes, serotonin receptor 2C, was significantly decreased (p =.001). Other genes, previously proposed to be differentially expressed in schizophrenia brain, were invariant in our analysis. CONCLUSIONS The differential expression of serotonin receptor 2C is particularly relevant for the development of new atypical antipsychotic drugs. The strategy presented here is useful to evaluate hypothesizes for the development of the disease proposed by other investigators.
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Affiliation(s)
- Anja Castensson
- Department of Evolutionary Biology, Uppsala University, Uppsala, Sweden
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Preece P, Virley DJ, Costandi M, Coombes R, Moss SJ, Mudge AW, Jazin E, Cairns NJ. An optimistic view for quantifying mRNA in post-mortem human brain. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2003; 116:7-16. [PMID: 12941456 DOI: 10.1016/s0169-328x(03)00208-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Quantitative human mRNA data are derived from post-mortem or biopsied tissue. RNA degradation, poor replication, a large mRNA variance and confounding factors such as brain pH and age of death are often cited, however, as objections to the data's reliability. A central question is whether post-mortem human mRNA can be treated as a statistically ordered system. TaqMan real-time RT-PCR was used to measure seven mRNAs in 513 cortical samples taken from 90 Alzheimer's disease and 81 control brains. Despite a high mRNA variance strong correlations were found between the mRNA transcripts in a single brain. Where a brain has a high/low level of one mRNA, the same brain invariably has a high/low level of other mRNAs; correlated order is present and allows removal of that source of variation common to all genes. Although levels of mRNA are highly variable between subjects (>1000-fold), quantitative order is present in post-mortem human mRNA, allowing effects due to pathology or gender to be isolated and tested for significance.
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Affiliation(s)
- Paul Preece
- Quantuum, Departamento de Neurología, Rua das Branas 7-Bajo-D, 15177 Mera, A Coruña, Galicia, Spain.
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49
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Abstract
The use of human brain tissue obtained at autopsy for neurochemical, pharmacological and physiological analyses is reviewed. RNA and protein samples have been found suitable for expression profiling by techniques that include RT-PCR, cDNA microarrays, western blotting, immunohistochemistry and proteomics. The rapid development of molecular biological techniques has increased the impetus for this work to be applied to studies of brain disease. It has been shown that most nucleic acids and proteins are reasonably stable post-mortem. However, their abundance and integrity can exhibit marked intra- and intercase variability, making comparisons between case-groups difficult. Variability can reveal important functional and biochemical information. The correct interpretation of neurochemical data must take into account such factors as age, gender, ethnicity, medicative history, immediate ante-mortem status, agonal state and post-mortem and post-autopsy intervals. Here we consider issues associated with the sampling of DNA, RNA and proteins using human autopsy brain tissue in relation to various ante- and post-mortem factors. We conclude that valid and practical measures of a variety of parameters may be made in human brain tissue, provided that specific factors are controlled.
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Affiliation(s)
- Matthew R Hynd
- Department of Biochemistry, University of Queensland, Brisbane, Australia
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50
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Abstract
Chronic cocaine use in humans and animal models is known to lead to pronounced alterations in neuronal function in brain regions associated with drug reinforcement. To evaluate whether the alterations in gene expression in cocaine overdose victims are associated with specific dopamine populations in the midbrain, cDNA arrays and western blotting were used to compare gene and protein expression patterns between cocaine overdose victims and age-matched controls in the ventral tegmental area (VTA) and lateral substantia nigra (l-SN). Array analysis revealed significant up-regulation of numerous transcripts in the VTA, but not in the l-SN, of cocaine overdose victims including NMDAR1, GluR2, GluR5 and KA2 receptor mRNA (p < 0.05). No significant alterations between overdose victims and controls were observed for GluR1, R3 or R4 mRNA levels. Correspondingly, western blot analysis revealed VTA-selective up-regulation of CREB (p < 0.01), NMDAR1 (p < 0.01), GluR2 (p < 0.05), GluR5 (p < 0.01) and KA2 (p < 0.05) protein levels of cocaine overdose victims. The present results indicate that selective alterations of CREB and certain ionotropic glutamate receptor (iGluR) subtypes appear to be associated with chronic cocaine use in humans in a region-specific manner. Moreover, as subunit composition determines the functional properties of iGluRs, the observed changes may indicate alterations in the excitability of dopamine transmission underlying long-term biochemical and behavioral effects of cocaine in humans.
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Affiliation(s)
- Wen-Xue Tang
- Department of Pharmacology and Psychiatry/Behavioral Sciences, Yerkes National Primate Research Center, Neuroscience Division, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Wendy H. Fasulo
- Department of Pharmacology and Psychiatry/Behavioral Sciences, Yerkes National Primate Research Center, Neuroscience Division, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Deborah C. Mash
- Department of Neurology and Molecular and Cellular Pharmacology, University of Miami School of Medicine, Miami, Florida, USA
| | - Scott E. Hemby
- Department of Pharmacology and Psychiatry/Behavioral Sciences, Yerkes National Primate Research Center, Neuroscience Division, Emory University School of Medicine, Atlanta, Georgia, USA
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