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Delaune V, Lacotte S, Gex Q, Slits F, Kahler-Quesada A, Lavallard V, Peloso A, Orci LA, Berney T, Toso C. Effects of remote ischaemic preconditioning on intraportal islet transplantation in a rat model. Transpl Int 2018; 32:323-333. [PMID: 30318858 DOI: 10.1111/tri.13360] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 07/23/2018] [Accepted: 10/08/2018] [Indexed: 12/29/2022]
Abstract
Remote ischaemic preconditioning (RIPC), which is the intermittent interruption of blood flow to a site distant from the target organ, is known to improve solid organ resistance to ischaemia-reperfusion injury. This procedure could be of interest in islet transplantation to mitigate hypoxia-related loss of islet mass after isolation and transplantation. Islets isolated from control or RIPC donors were analyzed for yield, metabolic activity, gene expression and high mobility group box-1 (HMGB1) content. Syngeneic marginal mass transplantation was performed in four streptozotocin-induced diabetic groups: control, RIPC in donor only, RIPC in recipient only, and RIPC in donor and recipient. Islets isolated from RIPC donors had an increased yield of 20% after 24 h of culture compared to control donors (P = 0.007), linked to less cell death (P = 0.08), decreased expression of hypoxia-related genes (Hif1a P = 0.04; IRP94 P = 0.008), and increased intra-cellular (P = 0.04) and nuclear HMGB1. The use of RIPC in recipients only did not allow for reversal of diabetes, with increased serum HMGB1 at day 1; the three other groups demonstrated significantly better outcomes. Performing RIPC in the donors increases islet yield and resistance to hypoxia. Validation is needed, but this strategy could help to decrease the number of donors per islet recipient.
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Affiliation(s)
- Vaihere Delaune
- Hepatology and Transplantation Laboratory, Department of Surgery, Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Divisions of Abdominal and Transplantation Surgery, Department of Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Stéphanie Lacotte
- Hepatology and Transplantation Laboratory, Department of Surgery, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Quentin Gex
- Hepatology and Transplantation Laboratory, Department of Surgery, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Florence Slits
- Hepatology and Transplantation Laboratory, Department of Surgery, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Arianna Kahler-Quesada
- Hepatology and Transplantation Laboratory, Department of Surgery, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Vanessa Lavallard
- Cell Transplantation Laboratory, Department of Surgery, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Andrea Peloso
- Divisions of Abdominal and Transplantation Surgery, Department of Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Lorenzo A Orci
- Hepatology and Transplantation Laboratory, Department of Surgery, Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Divisions of Abdominal and Transplantation Surgery, Department of Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Thierry Berney
- Cell Transplantation Laboratory, Department of Surgery, Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Transplantation Division, Department of Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Christian Toso
- Hepatology and Transplantation Laboratory, Department of Surgery, Faculty of Medicine, University of Geneva, Geneva, Switzerland.,Divisions of Abdominal and Transplantation Surgery, Department of Surgery, Geneva University Hospitals, Geneva, Switzerland
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2
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Tikamdas R, Singhal S, Zhang P, Smith JA, Krause EG, Stevens SM, Song S, Liu B. Ischemia-responsive protein 94 is a key mediator of ischemic neuronal injury-induced microglial activation. J Neurochem 2017. [PMID: 28640931 DOI: 10.1111/jnc.14111] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Neuroinflammation, especially activation of microglia, the key immune cells in the brain, has been proposed to contribute to the pathogenesis of ischemic stroke. However, the dynamics and the potential mediators of microglial activation following ischemic neuronal injury are not well understood. In this study, using oxygen/glucose deprivation and reoxygenation with neuronal and microglial cell cultures as an in vitro model of ischemic neuronal injury, we set out to identify neuronal factors released from injured neurons that are capable of inducing microglial activation. Conditioned media (CM) from hippocampal and cortical neurons exposed to oxygen/glucose deprivation and reoxygenation induced significant activation of microglial cells as well as primary microglia, evidenced by up-regulation of inducible nitric oxide synthase, increased production of nitrite and reactive oxygen species, and increased expression of microglial markers. Mechanistically, neuronal ischemia-responsive protein 94 (Irp94) was a key contributor to microglial activation since significant increase in Irp94 was detected in the neuronal CM following ischemic insult and immunodepletion of Irp94 rendered ischemic neuronal CM ineffective in inducing microglial activation. Ischemic insult-augmented oxidative stress was a major facilitator of neuronal Irp94 release, and pharmacological inhibition of NADPH oxidase significantly reduced the ischemic injury-induced neuronal reactive oxygen species production and Irp94 release. Taken together, these results indicate that neuronal Irp94 may play a pivotal role in the propagation of ischemic neuronal damage. Continued studies may help identify Irp94 and/or related proteins as potential therapeutic targets and/or diagnostic/prognostic biomarkers for managing ischemia-associated brain disorders.
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Affiliation(s)
- Rajiv Tikamdas
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida, USA
| | - Sarthak Singhal
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida, USA
| | - Ping Zhang
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida, USA
| | - Justin A Smith
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida, USA
| | - Eric G Krause
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida, USA
| | - Stanley M Stevens
- Department of Cell Biology, Microbiology and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, Florida, USA
| | - Sihong Song
- Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, Florida, USA
| | - Bin Liu
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida, USA
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3
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Barger SW. Gene regulation and genetics in neurochemistry, past to future. J Neurochem 2016; 139 Suppl 2:24-57. [PMID: 27747882 DOI: 10.1111/jnc.13629] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 03/01/2016] [Accepted: 03/30/2016] [Indexed: 12/14/2022]
Abstract
Ask any neuroscientist to name the most profound discoveries in the field in the past 60 years, and at or near the top of the list will be a phenomenon or technique related to genes and their expression. Indeed, our understanding of genetics and gene regulation has ushered in whole new systems of knowledge and new empirical approaches, many of which could not have even been imagined prior to the molecular biology boon of recent decades. Neurochemistry, in the classic sense, intersects with these concepts in the manifestation of neuropeptides, obviously dependent upon the central dogma (the established rules by which DNA sequence is eventually converted into protein primary structure) not only for their conformation but also for their levels and locales of expression. But, expanding these considerations to non-peptide neurotransmitters illustrates how gene regulatory events impact neurochemistry in a much broader sense, extending beyond the neurochemicals that translate electrical signals into chemical ones in the synapse, to also include every aspect of neural development, structure, function, and pathology. From the beginning, the mutability - yet relative stability - of genes and their expression patterns were recognized as potential substrates for some of the most intriguing phenomena in neurobiology - those instances of plasticity required for learning and memory. Near-heretical speculation was offered in the idea that perhaps the very sequence of the genome was altered to encode memories. A fascinating component of the intervening progress includes evidence that the central dogma is not nearly as rigid and consistent as we once thought. And this mutability extends to the potential to manipulate that code for both experimental and clinical purposes. Astonishing progress has been made in the molecular biology of neurochemistry during the 60 years since this journal debuted. Many of the gains in conceptual understanding have been driven by methodological progress, from automated high-throughput sequencing instruments to recombinant-DNA vectors that can convey color-coded genetic modifications in the chromosomes of live adult animals. This review covers the highlights of these advances, both theoretical and technological, along with a brief window into the promising science ahead. This article is part of the 60th Anniversary special issue.
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Affiliation(s)
- Steven W Barger
- Department of Geriatrics, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA. .,Geriatric Research Education and Clinical Center, Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, USA.
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Zuo D, Subjeck J, Wang XY. Unfolding the Role of Large Heat Shock Proteins: New Insights and Therapeutic Implications. Front Immunol 2016; 7:75. [PMID: 26973652 PMCID: PMC4771732 DOI: 10.3389/fimmu.2016.00075] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 02/15/2016] [Indexed: 11/13/2022] Open
Abstract
Heat shock proteins (HSPs) of eukaryotes are evolutionarily conserved molecules present in all the major intracellular organelles. They mainly function as molecular chaperones and participate in maintenance of protein homeostasis in physiological state and under stressful conditions. Despite their relative abundance, the large HSPs, i.e., Hsp110 and glucose-regulated protein 170 (Grp170), have received less attention compared to other conventional HSPs. These proteins are distantly related to the Hsp70 and belong to Hsp70 superfamily. Increased sizes of Hsp110 and Grp170, due to the presence of a loop structure, result in their exceptional capability in binding to polypeptide substrates or non-protein ligands, such as pathogen-associated molecules. These interactions that occur in the extracellular environment during tissue injury or microbial infection may lead to amplification of an immune response engaging both innate and adaptive immune components. Here, we review the current advances in understanding these large HSPs as molecular chaperones in proteostasis control and immune modulation as well as their therapeutic implications in treatment of cancer and neurodegeneration. Given their unique immunoregulatory activities, we also discuss the emerging evidence of their potential involvement in inflammatory and immune-related diseases.
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Affiliation(s)
- Daming Zuo
- Department of Immunology, Southern Medical University, Guangzhou, China; State Key Laboratory of Organ Failure Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China; Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - John Subjeck
- Department of Cellular Stress Biology, Roswell Park Cancer Institute , Buffalo, NY , USA
| | - Xiang-Yang Wang
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA, USA; VCU Massey Cancer Center, Virginia Commonwealth University, Richmond, VA, USA; VCU Institute of Molecular Medicine, Virginia Commonwealth University, Richmond, VA, USA
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Shi GX, Andres DA, Cai W. Ras family small GTPase-mediated neuroprotective signaling in stroke. Cent Nerv Syst Agents Med Chem 2012; 11:114-37. [PMID: 21521171 DOI: 10.2174/187152411796011349] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 01/18/2011] [Accepted: 03/22/2011] [Indexed: 12/31/2022]
Abstract
Selective neuronal cell death is one of the major causes of neuronal damage following stroke, and cerebral cells naturally mobilize diverse survival signaling pathways to protect against ischemia. Importantly, therapeutic strategies designed to improve endogenous anti-apoptotic signaling appear to hold great promise in stroke treatment. While a variety of complex mechanisms have been implicated in the pathogenesis of stroke, the overall mechanisms governing the balance between cell survival and death are not well-defined. Ras family small GTPases are activated following ischemic insults, and in turn, serve as intrinsic switches to regulate neuronal survival and regeneration. Their ability to integrate diverse intracellular signal transduction pathways makes them critical regulators and potential therapeutic targets for neuronal recovery after stroke. This article highlights the contribution of Ras family GTPases to neuroprotective signaling cascades, including mitogen-activated protein kinase (MAPK) family protein kinase- and AKT/PKB-dependent signaling pathways as well as the regulation of cAMP response element binding (CREB), Forkhead box O (FoxO) and hypoxiainducible factor 1(HIF1) transcription factors, in stroke.
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Affiliation(s)
- Geng-Xian Shi
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, 741 S. Limestone St., Lexington, KY 40536-0509, USA.
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Lee KR, Kim SW, Kim YK, Kwon K, Choi JS, Yu K, Kwon OY. Silkworm hemolymph down-regulates the expression of endoplasmic reticulum chaperones under radiation-irradiation. Int J Mol Sci 2011; 12:4456-64. [PMID: 21845089 PMCID: PMC3155362 DOI: 10.3390/ijms12074456] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Revised: 05/30/2011] [Accepted: 06/24/2011] [Indexed: 11/19/2022] Open
Abstract
We demonstrated that up-regulation of gene expression of endoplasmic reticulum (ER) chaperones (BiP, calnexin, calreticulin, ERp29) and ER membrane kinases (IRE1, PERK, ATF6) was induced by radiation in neuronal PC12 cells. However, addition of silkworm, Bombyx mori, hemolymph to irradiated cells resulted in an obvious decrease in expression of these genes, compared with a single radiation treatment. In contrast, one of the ER chaperones, “ischemia-responsive protein 94 kDa” (irp94), was up-regulated by radiation. However, addition of silkworm hemolymph resulted in no change in the expression of irp94, with an expression pattern that differed from that of ER chaperones. Based on these results, we propose that silkworm hemolymph contains factors that regulate a decrease in the expression of ER chaperones under radiation-irradiation conditions, with the exception of irp94, which is not down-regulated. We suggest that this difference in the molecular character of irp94 may provide a clue to the biological functions associated with ER stress pathways, particularly the effects of radiation.
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Affiliation(s)
- Kyeong Ryong Lee
- Department of Emergency Medicine, Konkuk University Medical Center, Seoul 143-729, Korea; E-Mail:
| | - Seung-Whan Kim
- Department of Emergency Medicine, Chungnam National University Hospital, Taejon 301-721, Korea; E-Mail:
| | - Young Kook Kim
- Department of Social Spots, Joongbu University, Chungnam 312-702, Korea; E-Mail:
| | - Kisang Kwon
- Department of Anatomy, College of Medicine, Chungnam National University, Taejon 301-747, Korea; E-Mail:
| | - Jong-Soon Choi
- Division of Life Science, Korea Basic Science Institute, Taejon 305-333, Korea; E-Mail:
- Graduate School of Analytical Science and Technology, Chungnam National University, Taejon 660-758, Korea
| | - Kweon Yu
- Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Taejon 305-806, Korea; E-Mail:
| | - O-Yu Kwon
- Department of Anatomy, College of Medicine, Chungnam National University, Taejon 301-747, Korea; E-Mail:
- Author to whom correspondence should be addressed: E-Mail: ; Tel.: +81-42-580-8206; Fax: +81-42-586-4800
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7
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Proteomic identification of hippocampal proteins vulnerable to oxidative stress in excitotoxin-induced acute neuronal injury. Neurobiol Dis 2011; 43:706-14. [PMID: 21669285 DOI: 10.1016/j.nbd.2011.05.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 05/02/2011] [Accepted: 05/28/2011] [Indexed: 12/26/2022] Open
Abstract
Excitotoxicity is involved in seizure-induced acute neuronal death, hypoxic-ischemic encephalopathy, and chronic neurodegenerative conditions such as Alzheimer's disease. Although oxidative stress has been implicated in excitotoxicity, the target proteins of oxidative damage during the course of excitotoxic cell death are still unclear. In the present study, we performed 2D-oxyblot analysis and mass spectrometric amino acid sequencing to identify proteins that were vulnerable to oxidative damage in the rat hippocampus during kainic acid (KA)-induced status epilepticus. We first investigated the time course in which oxidative protein damage occurred using immunohistochemistry. Carbonylated proteins, a manifestation of protein oxidation, were detected in hippocampal neurons as early as 3h after KA administration. Immunoreactivity for 8-hydroxy-2'-deoxyguanosine (8-OHdG) was also elevated at the same time point. The increase in oxidative damage to proteins and DNA occurred concomitantly with the early morphological changes in KA-treated rat hippocampus, i.e., changes in chromatin distribution and swelling of rough endoplasmic reticulum and mitochondria, which preceded the appearance of morphological features of neuronal death such as pyknotic nuclei and hypereosinophilic cytoplasm. Proteomic analysis revealed that several hippocampal proteins were consistently carbonylated at this time point, including heat shock 70kDa protein 4, valosin-containing protein, mitochondrial inner membrane protein (mitofilin), α-internexin, and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein (14-3-3 protein). We propose that oxidative damage to these proteins may be one of the upstream events in the molecular pathway leading to excitotoxic cell death in KA-treated rat hippocampus, and these proteins may be targets of therapeutic intervention for seizure-induced neuronal death.
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8
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Yoneyama M, Iwamoto N, Nagashima R, Sugiyama C, Kawada K, Kuramoto N, Shuto M, Ogita K. Altered expression of heat shock protein 110 family members in mouse hippocampal neurons following trimethyltin treatment in vivo and in vitro. Neuropharmacology 2008; 55:693-703. [DOI: 10.1016/j.neuropharm.2008.06.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2007] [Revised: 04/19/2008] [Accepted: 06/02/2008] [Indexed: 10/21/2022]
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9
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Srivastava RM, Varalakshmi C, Khar A. The Ischemia-Responsive Protein 94 (Irp94) Activates Dendritic Cells through NK Cell Receptor Protein-2/NK Group 2 Member D (NKR-P2/NKG2D) Leading to Their Maturation. THE JOURNAL OF IMMUNOLOGY 2008; 180:1117-30. [DOI: 10.4049/jimmunol.180.2.1117] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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10
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Abstract
Neuronal cell death is a major feature of various diseases, including brain ischemia, neuronal degenerative diseases, and traumatic injury, suggesting the importance of investigating the mechanisms that mediate neuronal cell death. Although the various factors that contribute to brain ischemia have been defined and the mechanism through which each factor causes neuronal cell death has been investigated, definite strategies have not been established. In this brief review, we focus on two important mechanisms that contribute to the pathogenesis of brain ischemia. First, we discuss the glutamate theory, a proposed mechanism for the understanding of ischemia-induced neuronal cell death. Second, an accumulation of recent molecular neurobiology evidence regarding the dysfunction of a cellular organelle, the endoplasmic reticulum (ER), suggests that it plays a major role in the pathogenesis of neuronal cell death. Whereas the former theory reflects the role of neuron-specific factors in the induction of cell death, the stress response of the ER for maintenance of its function is regarded as a defense mechanism. Because hypoxia, another major factor in ischemia, results in further dysfunction of the ER, studies on the malfunction of this cellular organelle may facilitate the development of novel strategies to block ischemia-induced cell death.
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Affiliation(s)
- Satoshi Ogawa
- Department of Neuroanatomy, Kanazawa University Medical School, Takara-machi, Kanazawa City, Ishikawa, Japan.
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11
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Tsapara A, Matter K, Balda MS. The heat-shock protein Apg-2 binds to the tight junction protein ZO-1 and regulates transcriptional activity of ZONAB. Mol Biol Cell 2006; 17:1322-30. [PMID: 16407410 PMCID: PMC1382320 DOI: 10.1091/mbc.e05-06-0507] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2005] [Revised: 12/20/2005] [Accepted: 12/28/2005] [Indexed: 01/12/2023] Open
Abstract
The tight junction adaptor protein ZO-1 regulates intracellular signaling and cell proliferation. Its Src homology 3 (SH3) domain is required for the regulation of proliferation and binds to the Y-box transcription factor ZO-1-associated nucleic acid binding protein (ZONAB). Binding of ZO-1 to ZONAB results in cytoplasmic sequestration and hence inhibition of ZONAB's transcriptional activity. Here, we identify a new binding partner of the SH3 domain that modulates ZO-1-ZONAB signaling. Expression screening of a cDNA library with a fusion protein containing the SH3 domain yielded a cDNA coding for Apg-2, a member of the heat-shock protein 110 (Hsp 110) subfamily of Hsp70 heat-shock proteins, which is overexpressed in carcinomas. Regulated depletion of Apg-2 in Madin-Darby canine kidney cells inhibits G(1)/S phase progression. Apg-2 coimmunoprecipitates with ZO-1 and partially localizes to intercellular junctions. Junctional recruitment and coimmunoprecipitation with ZO-1 are stimulated by heat shock. Apg-2 competes with ZONAB for binding to the SH3 domain in vitro and regulates ZONAB's transcriptional activity in reporter gene assays. Our data hence support a model in which Apg-2 regulates ZONAB function by competing for binding to the SH3 domain of ZO-1 and suggest that Apg-2 functions as a regulator of ZO-1-ZONAB signaling in epithelial cells in response to cellular stress.
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Affiliation(s)
- Anna Tsapara
- Division of Cell Biology, Institute of Ophthalmology, University College London, London EC1V 9EL, UK
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12
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Yamane M, Liu M, Kaneda H, Uhlig S, Waddell TK, Keshavjee S. Reperfusion-induced gene expression profiles in rat lung transplantation. Am J Transplant 2005; 5:2160-9. [PMID: 16095495 DOI: 10.1111/j.1600-6143.2005.01017.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Ischemia-Reperfusion (I/R) injury after lung transplantation (LTx) can lead to significant morbidity and mortality in recipients. In an attempt to improve our understanding of molecular mechanisms of I/R injury, we examined the changes in gene expression levels in a rat lung transplant model using oligonucleotide microarrays. Lewis rat lung grafts were stored for 6 or 24 h followed by transplantation and reperfusion for 2 h. Lung tissues were taken before and after flushing the grafts, before implantation, and after 2 h of reperfusion. RNA samples were examined with Affymetrix rat microarray chips and RT-PCR was performed to validate significant changes in gene expression. Microarray analysis showed 404 genes that were up-regulated more than 2-fold after reperfusion compared to cold ischemic lungs, and 187 genes that were down-regulated. Using RT-PCR, we confirmed the response pattern of several specific gene transcripts from the microarray analysis. Among these, up-regulation in transcripts of transcription factors, adhesion molecules, pro-coagulant factors and pro-inflammatory cytokines were identified. The differential gene regulation during the I/R process can be considered as molecular signatures for the changes of cellular metabolism, functions and injury. Reperfusion-induced genes related to inflammatory response may contribute to graft dysfunction in LTx.
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Affiliation(s)
- Masaomi Yamane
- Thoracic Surgery Research Laboratory, Toronto General Hospital Research Institute, University Health Network, University of Toronto, Toronto, Ontario, Canada
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Tohda M, Watanabe H. Molecular cloning and characterization of a novel sequence, vof-16, with enhanced expression in permanent ischemic rat brain. Biol Pharm Bull 2005; 27:1228-35. [PMID: 15305027 DOI: 10.1248/bpb.27.1228] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We reported previously that chronic hypoperfusion induced by permanent occlusion of the bilateral common carotid arteries (2VO) in rats caused progressive cognitive deficits and neuronal damage in the hippocampus and the white matter. These changes are similar to those observed in human dementia. Reverse transcription-polymerase chain reaction (RT-PCR) differential display was carried out to identify mRNAs encoding the intrinsic factors involved in permanent ischemia from the 2VO rat brain. Over 20 clones which showed different expression levels in 2VO and sham-operated rats were isolated. One of these, named vof-16, was markedly enhanced the expression by 2VO. The whole sequence of vof-16 mRNA was 2098 nt. The distribution of vof-16 transcripts was examined by RT-PCR and in situ hybridization. The results revealed that vof-16 was abundant in the hippocampus, the tenia tecta, the piriform cortex and the area around the aorta. The expression levels of vof-16 in 2VO and sham-operated rat hippocampus were determined by a quantitative PCR method. The expression was abundant in the hippocampus of rats with cognitive impairment induced by 2VO. In contrast, the expression levels of vof-16 were lower in the 2VO rats with no impairment and in sham-operated rats. These results suggest that the expression levels of vof-16 may be related to the cognitive impairment induced by chronic ischemia after 2VO.
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Affiliation(s)
- Michihisa Tohda
- Department of Pharmacology, Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, Toyama, Japan.
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14
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Moriya M, Ochiai M, Yuasa HJ, Suzuki N, Yazawa M. Identification of Ca2+-dependent calmodulin-binding proteins in rat spermatogenic cells as complexes of the heat-shock proteins. Mol Reprod Dev 2004; 69:316-24. [PMID: 15349844 DOI: 10.1002/mrd.20134] [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] [Indexed: 11/06/2022]
Abstract
Ca2+-calmodulin (CaM)-binding proteins in rat testes were characterized by assays for CaM-binding activity using the CaM-overlay method on transblots of electrophoresed gels and purification by gel-filtration, ion exchange, and adsorption chromatographies. A major CaM-binding protein complex (CaMBP) was identified and found to be comprised of three proteins with molecular masses 110, 100, and 70 kDa. Amino acid sequence analyses of lysylendopeptidase digests from these proteins indicated that all of the constituents of CaMBP are very similar to the members of the heat-shock protein family, i.e., the 110-kDa protein is similar to the APG-2/94 kDa rat ischemia-responsive protein, the 100-kDa protein is similar to the rat counterpart of the mouse APG-1/94 kDa osmotic stress protein, and the 70-kDa protein is similar to the rat testis-specific major heat-shock protein (HSP70). Immunohistochemistry using anti-CaMBP and anti-CaM antibodies demonstrated that CaMBP was co-localized with CaM in the cytoplasm of pachytene spermatocytes and nuclei of round spermatids. In addition, CaMBP, but not CaM, was localized at a high level in the residual bodies of elongated spermatids. The possible relevance of CaMBP to regulation of cell cycle progression and spermatogenesis is discussed in this paper.
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Affiliation(s)
- Megumi Moriya
- Laboratory of Biochemistry, The Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan.
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Paschen W. Endoplasmic reticulum: a primary target in various acute disorders and degenerative diseases of the brain. Cell Calcium 2003; 34:365-83. [PMID: 12909082 DOI: 10.1016/s0143-4160(03)00139-8] [Citation(s) in RCA: 150] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Changes in neuronal calcium activity in the various subcellular compartments have divergent effects on affected cells. In the cytoplasm and mitochondria, where calcium activity is normally low, a prolonged excessive rise in free calcium levels is believed to be toxic, in the endoplasmic reticulum (ER), in contrast, calcium activity is relatively high and severe stress is caused by a depletion of ER calcium stores. Besides its role in cellular calcium signaling, the ER is the site where membrane and secretory proteins are folded and processed. These calcium-dependent processes are fundamental to normal cell functioning. Under conditions of ER dysfunction unfolded proteins accumulate in the ER lumen, a signal responsible for activation of the unfolded protein response (UPR) and the ER-associated degradation (ERAD). UPR is characterized by activation of two ER-resident kinases, PKR-like ER kinase (PERK) and IRE1. PERK induces phosphorylation of the eukaryotic initiation factor (eIF2alpha), resulting in a shut-down of translation at the initiation step. This stress response is needed to block new synthesis of proteins that cannot be correctly folded, and thus to protect cells from the effect of unfolded proteins which tend to form toxic aggregates. IRE1, on the other hand, is turned after activation into an endonuclease that cuts out a sequence of 26 bases from the coding region of xbp1 mRNA. Processed xbp1 mRNA is translated into the respective protein, an active transcription factor specific for ER stress genes such as grp78. In acute disorders and degenerative diseases, the ER calcium pool is a primary target of toxic metabolites or intermediates, such as oxygen free radicals, produced during the pathological process. Affected neurons need to activate the entire UPR to cope with the severe form of stress induced by ER dysfunction. This stress response is however hindered under conditions where protein synthesis is suppressed to such an extent that processed xbp1 mRNA is not translated into the processed XBP1 protein (XBP1(proc)). Furthermore, activation of ERAD is important for the degradation of unfolded proteins through the ubiquitin/proteasomal pathway, which is impaired in acute disorders and degenerative diseases, resulting in further ER stress. ER functioning is thus impaired in two different ways: first by the direct action of toxic intermediates, produced in the course of the pathological process, hindering vital ER reactions, and second by the inability of cells to fully activate UPR and ERAD, leaving them unable to withstand the severe form of stress induced by ER dysfunction.
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Affiliation(s)
- Wulf Paschen
- Department of Experimental Neurology, Max-Planck-Institute for Neurological Research, 50931 Koeln, Germany.
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16
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Phosphorylation of cAMP response element-binding protein in hippocampal neurons as a protective response after exposure to glutamate in vitro and ischemia in vivo. J Neurosci 2002. [PMID: 11717354 DOI: 10.1523/jneurosci.21-23-09204.2001] [Citation(s) in RCA: 208] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Although accumulating evidence indicates that cAMP response element-binding protein (CREB) phosphorylation mediates not only synaptic plasticity but also survival of certain neurons, it remains uncertain whether CREB phosphorylation induced after metabolic insult leads to CRE-mediated gene transcription and is involved in cell survival or not. In the present study, we clarified that (1) CREB phosphorylation and ischemic tolerance induced after preconditioning ischemia in the hippocampal neurons was abolished by MK801 administration in gerbil global ischemia model, (2) CREB phosphorylation induced after exposure to glutamate in cultured neurons was inhibited by removal of extracellular calcium, by MK801 and by an inhibitor of calcium-calmodulin-dependent protein kinase (CaMK) II and IV, (3) inhibitor of CaMK II-IV or CRE-decoy oligonucleotide suppressed upregulation of BCL-2 expression and accelerated neuronal damage after exposure to glutamate, and (4) CREB phosphorylation induced in the hippocampal neurons after ischemia and in cultured neurons after exposure to glutamate was followed by CRE-mediated gene transcription in transgenic mice with a CRE-LacZ reporter. Our results suggest that CREB phosphorylation in neurons after ischemia and exposure to glutamate is induced by NMDA receptor-gated calcium influx and subsequent activation of CaMK II-IV and that CREB phosphorylation after metabolic stress might show a neuroprotective response through CRE-mediated gene induction.
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17
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Lee MY, Choi YS, Choi JS, Min DS, Chun MH, Kim ON, Lee SB, Kim SY. An immunohistochemical study of APG-2 protein in the rat hippocampus after transient forebrain ischemia. Brain Res 2002; 924:237-41. [PMID: 11750909 DOI: 10.1016/s0006-8993(01)03295-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The cellular localization and spatiotemporal expression pattern of APG-2 protein, a member of the heat shock protein 110 family, were investigated in the rat hippocampus after transient forebrain ischemia. The spatiotemporal patterns of immunoreactivity of both APG-2 and glial fibrillary acidic protein were very similar, indicating that reactive astrocytes express APG-2, which was confirmed by double immunofluorescence histochemistry. Colocalization of APG-2 and a neuronal marker NeuN in the neurons of the CA2 and CA3 subfields was also confirmed.
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Affiliation(s)
- Mun-Yong Lee
- Department of Anatomy, College of Medicine, The Catholic University of Korea, Seoul 137-701, South Korea
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18
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Tanaka S, Kitagawa K, Ohtsuki T, Yagita Y, Takasawa K, Hori M, Matsumoto M. Synergistic induction of HSP40 and HSC70 in the mouse hippocampal neurons after cerebral ischemia and ischemic tolerance in gerbil hippocampus. J Neurosci Res 2002; 67:37-47. [PMID: 11754079 DOI: 10.1002/jnr.10078] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
An ischemia-induced gene was screened using a differential display technique in mouse transient forebrain ischemia. One of the ischemia-responsive clones was found to encode mouse hsp40. HSP40 has a critical regulatory function in the HSC70 ATPase activity. Expression of hsp40 mRNA was low in the nonischemic mouse hippocampus, but it was significantly upregulated 4 hr after ischemia by Northern blot analysis. In situ hybridization analysis revealed hsp40 mRNA induction in the neuron. HSP40 protein expression was also enhanced in the pyramidal and dentate granular neurons from 2 to 4 days after ischemia. The temporal expression and distribution profile of HSC70 protein was similar to that of HSP40, and both proteins were colocalized in ischemic hippocampal neurons. In the gerbil transient forebrain ischemia model, both HSP40 and HSC70 proteins were expressed strongly in ischemia-resistant CA3 neurons and dentate granule cells 1 day after 5 min ischemia, but were not expressed in vulnerable CA1 neurons. However, both proteins were in parallel expressed in the tolerance-acquired CA1 neurons. Based on the current observation that both HSP40 and HSC70 proteins were synergistically expressed in the ischemia-resistant and tolerance-acquired neurons, cochaperone HSP40 may play a significant role against postischemic neuronal response and lead to cell survival through interaction with simultaneously induced HSC70.
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Affiliation(s)
- Shigeru Tanaka
- Division of Strokology, Department of Internal Medicine and Therapeutics, Osaka University Graduate School of Medicine, Osaka, Japan.
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19
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Ogita K, Takagi R, Oyama N, Okuda H, Ito F, Okui M, Shimizu N, Yoneda Y. Decrease in level of APG-2, a member of the heat shock protein 110 family, in murine brain following systemic administration of kainic acid. Neuropharmacology 2001; 41:285-93. [PMID: 11522319 DOI: 10.1016/s0028-3908(01)00081-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
APG-2 belongs to the heat shock protein 110 family. Although kainic acid (KA)-induced seizures are known to elicit expression of inducible heat shock protein 70 (HSP70) in the brain, no investigation has been carried out on the APG-2 level after excitatory amino acid-induced seizures. By means of an immunoblot assay, we determined the levels of HSP70 and APG-2 in discrete brain structures of mice after a single intraperitoneal injection of KA or N-methyl-D-aspartic acid (NMDA). APG-2 level was significantly decreased in frontal cortex, hippocampus, and striatum three days after the administration of KA, while HSP70 level was increased in these regions following the administration. In any of these regions, APG-2 levels were returned to the control levels 10 days after the administration. However, no significant changes were observed in levels of both HSP70 and APG-2 in hypothalamus, midbrain, medulla-pons, and cerebellum of the mice. By contrast, NMDA administration did not significantly affect both levels in any of the regions examined. These findings indicate that the transient decrease in APG-2 expression is one of the intracellular events elicited by signals peculiar to KA, but not by those peculiar to NMDA, in telencephalon of murine brain.
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Affiliation(s)
- K Ogita
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Setsunan University, 45-1 Nagaotoge-cho, Hirakata, Osaka 573-0101, Japan.
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20
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Yagita Y, Kitagawa K, Ohtsuki T, Tanaka S, Hori M, Matsumoto M. Induction of the HSP110/105 family in the rat hippocampus in cerebral ischemia and ischemic tolerance. J Cereb Blood Flow Metab 2001; 21:811-9. [PMID: 11435793 DOI: 10.1097/00004647-200107000-00006] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Recently, the authors isolated a novel gene of the HSP110 family, ischemia responsive protein 94 kDa (irp94), and demonstrated the expression of this gene after transient forebrain ischemia. In the current study, the authors investigated the expression profiles of all HSP110 family members including hsp110/105 and osp94/apg-1, after transient forebrain ischemia using rat four-vessel occlusion model. Among three members of the HSP110 family, induction of hsp110/105 was the most prominent after ischemia. hsp110/105 mRNA expression was clearly enhanced from 4 to 24 hours after a 6-minute or longer ischemic period. First, hsp110/105 mRNA expression was induced in the dentate gyrus, and later in the pyramidal layer. HSP110/105 protein expression also was enhanced by a 6-minute or longer period of ischemia. Profiles of HSP110/105 expression after ischemia were similar to those of inducible HSP70. After transient forebrain ischemia for 10 minutes, HSP110/105 protein was induced in the dentate gyrus and the CA3 pyramidal layer, but not in the CA1 pyramidal neurons. However, 6 minutes of ischemia induced the HSP110/105 protein, as well as the HSP70 protein, in the CA1 region. CA1 pyramidal neurons expressing HSP110/105 acquired tolerance against subsequent severe ischemia. In conclusion, HSP110/105 showed the most prominent induction after ischemia among the three HSP110 gene family members. Colocalization of HSP110/105 and HSP70 in the CA1 neurons that acquired tolerance suggested that induced HSP110/105 might contribute to ischemic tolerance together with HSP70.
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Affiliation(s)
- Y Yagita
- Division of Strokology, Department of Internal Medicine and Therapeutics, Osaka University Graduate School of Medicine, Osaka, Japan
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21
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Larsen PM, Fey SJ, Larsen MR, Nawrocki A, Andersen HU, Kähler H, Heilmann C, Voss MC, Roepstorff P, Pociot F, Karlsen AE, Nerup J. Proteome analysis of interleukin-1beta--induced changes in protein expression in rat islets of Langerhans. Diabetes 2001; 50:1056-63. [PMID: 11334408 DOI: 10.2337/diabetes.50.5.1056] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The intracellular molecular events involved in the beta-cell death process are complex but poorly understood. Cytokines, e.g., interleukin (IL)-1beta, may play a crucial role in inducing this process. Protein synthesis is necessary for the deleterious effect of IL-1, and induction of both protective and deleterious proteins has been described. To characterize the rather complex pattern of islet protein expression in rat islets in response to IL-1, we have attempted to identify proteins of altered expression level after IL-1 exposure by 2D gel electrophoresis and mass spectrometry. Of 105 significantly changed (i.e., up- or downregulated or de novo-induced) protein spots, we obtained positive protein identification for 60 protein spots. The 60 identifications corresponded to 57 different proteins. Of these, 10 proteins were present in two to four spots, suggesting that posttranslatory modifications had occurred. In addition, 11 spots contained more than one protein. The proteins could be classified according to their function into the following groups: 1) energy transduction; 2) glycolytic pathway; 3) protein synthesis, chaperones, and protein folding; and 4) signal transduction, regulation, differentiation, and apoptosis. In conclusion, valuable information about the molecular mechanisms involved in cytokine-mediated beta-cell destruction was obtained by this approach.
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Affiliation(s)
- P M Larsen
- Center for Proteome Analysis, University of Southern Denmark, Odense
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22
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Easton DP, Kaneko Y, Subjeck JR. The hsp110 and Grp1 70 stress proteins: newly recognized relatives of the Hsp70s. Cell Stress Chaperones 2000; 5:276-90. [PMID: 11048651 PMCID: PMC312858 DOI: 10.1379/1466-1268(2000)005<0276:thagsp>2.0.co;2] [Citation(s) in RCA: 226] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2000] [Revised: 07/13/2000] [Accepted: 07/13/2000] [Indexed: 11/24/2022] Open
Abstract
Both the Grp170 and Hsp110 families represent relatively conserved and distinct sets of stress proteins, within a more diverse category that also includes the Hsp70s. All of these families are found in a wide variety of organisms from yeasts to humans. Although Hsp110s or Grp170s are not Hsp70s any more than Hsp70s are Hsp110s or Grp170s, it is still reasonable to refer to this combination of related families as the Hsp70 superfamily based on arguments discussed above and since no obvious prokaryotic Hsp110 or Grp170 has yet been identified. These proteins are related to their counterparts in the Hsp70/Grp78 family of eukaryotic stress proteins but are characterized by significantly larger molecular weights. The members of the Grp170 family are characterized by C-terminal ER retention sequences and are ER localized in yeasts and mammals. As a Grp, Grp170 is recognized to be coregulated with other major Grps by a well-known set of stress conditions, sometimes referred to as the unfolded protein response (Kozutsumi et al 1988; Nakaki et al 1989). The Hsp110 family members are localized in the nucleus and cytoplasm and, with other major Hsps, are also coregulated by a specific set of stress conditions, most notably including hyperthermic exposures. Hsp110 is sometimes called Hsp105, although it would be preferable to have a uniform term. The large Hsp70-like proteins are structurally similar to the Hsp70s but differ from them in important ways. In both the Grp170 and Hspl10 families, there is a long loop structure that is interposed between the peptide-binding ,-domain and the alpha-helical lid. In the Hsp110 family and Grp170, there are differing degrees of expansion in the alpha-helical domain and the addition of a C-terminal loop. This gives the appearance of much larger lid domains for Hsp110 and Grp170 compared with Hsp70. Both Hsp110 and Grp170 families have relatively conserved short sequences in the alpha-helical domain in the lid, which are conserved motifs in numerous proteins (we termed these motifs Magic and TedWylee as discussed earlier). The structural differences detailed in this review result in functional differences between the large (Grp170 and Hspl10) members of the Hsp70 superfamily, the most distinctive being an increased ability of these proteins to bind (hold) denatured polypeptides compared with Hsc70, perhaps related to the enlarged C-terminal helical domain. However, there is also a major difference between these large stress proteins; Hsp110 does not bind ATP in vitro, whereas Grp170 binds ATP avidly. The role of the Grp170 and Hsp110 stress proteins in cellular physiology is not well understood. Overexpression of Hsp110 in cultured mammalian cells increases thermal tolerance. Grp170 binds to secreted proteins in the ER and may be cooperatively involved in folding these proteins appropriately. These roles are similar to those of the Hsp70 family members, and, therefore, the question arises as to the differential roles played by the larger members of the superfamily. We have discussed evidence that the large members of the superfamily cooperate with members of the Hsp70 family, and these chaperones probably interact with a large number of chaperones and cochaperones in their functional activities. The fundamental point is that Hsp110 is found in conjunction with Hsp70 in the cytoplasm (and nucleus) and Grp170 is found in conjunction with78 in tha ER in every eucaryotic cell examined from yeast to humans. This would strongly argue that Hsp110 Grp170 exhibit functions in eucaryotes not effectively performed by Hsp70s or Grp78, respectively. Of interest in this respect is the observation that all Hsp110s loss of function or deletion mutants listed in the Drosophila deletion project database are lethal. The important task for the future is to determine the roles these conserved molecular chaperones play in normal and physiologically stressed cells.
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Affiliation(s)
- D P Easton
- Department of Biology, State University of New York College at Buffalo, 14222, USA.
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23
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Okui M, Ito F, Ogita K, Kuramoto N, Kudoh J, Shimizu N, Ide T. Expression of APG-2 protein, a member of the heat shock protein 110 family, in developing rat brain. Neurochem Int 2000; 36:35-43. [PMID: 10566957 DOI: 10.1016/s0197-0186(99)00095-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
APG-2 protein is a member of the heat shock protein 110 family, and it is thought to play an important role in the maintenance of neuronal functions under physiological and stress conditions. However, neither the tissue-distribution of APG-2 protein nor developmental change of its expression has been studied at the protein level. Therefore, we generated an antiserum against APG-2 protein and studied expression of this protein in rat brain and other tissues by use of the Western blot method. The results showed a high expression of APG-2 protein in various regions of the central nervous system (cerebral cortex, hippocampus, striatum, midbrain, hypothalamus, cerebellum, medulla pons, and spinal cord) throughout the entire postnatal stage. Similarly, a high level of APG-2 protein was detected in the whole brain of rat embryos and in adult rat tissues such as liver, lung, spleen, and kidney. In contrast, its expression in heart was high at postnatal days 1 and 3, but thereafter drastically decreased to a low level. Furthermore, APG-2 protein was detected in neuronal primary cultures prepared from rat cerebral cortex, and its level did not change notably during neuronal differentiation. These results show that APG-2 protein is constitutively expressed in various tissues and also in neuronal cells throughout the entire embryonic and postnatal period. suggesting that it might play an important role in these tissues under non-stress conditions.
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Affiliation(s)
- M Okui
- Department of Cellular and Molecular Biology, Hiroshima University School of Medicine, Japan
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