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Winter JM, Fresenius HL, Cunningham CN, Wei P, Keys HR, Berg J, Bott A, Yadav T, Ryan J, Sirohi D, Tripp SR, Barta P, Agarwal N, Letai A, Sabatini DM, Wohlever ML, Rutter J. Collateral deletion of the mitochondrial AAA+ ATPase ATAD1 sensitizes cancer cells to proteasome dysfunction. eLife 2022; 11:82860. [PMID: 36409067 DOI: 10.7554/elife.82860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Accepted: 11/20/2022] [Indexed: 11/23/2022] Open
Abstract
The tumor suppressor gene PTEN is the second most commonly deleted gene in cancer. Such deletions often include portions of the chromosome 10q23 locus beyond the bounds of PTEN itself, which frequently disrupts adjacent genes. Coincidental loss of PTEN-adjacent genes might impose vulnerabilities that could either affect patient outcome basally or be exploited therapeutically. Here, we describe how the loss of ATAD1, which is adjacent to and frequently co-deleted with PTEN, predisposes cancer cells to apoptosis triggered by proteasome dysfunction and correlates with improved survival in cancer patients. ATAD1 directly and specifically extracts the pro-apoptotic protein BIM from mitochondria to inactivate it. Cultured cells and mouse xenografts lacking ATAD1 are hypersensitive to clinically used proteasome inhibitors, which activate BIM and trigger apoptosis. This work furthers our understanding of mitochondrial protein homeostasis and could lead to new therapeutic options for the hundreds of thousands of cancer patients who have tumors with chromosome 10q23 deletion.
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Affiliation(s)
- Jacob M Winter
- Department of Biochemistry, University of Utah, Salt Lake City, United States
| | - Heidi L Fresenius
- Department of Chemistry & Biochemistry, University of Toledo, Toledo, United States
| | - Corey N Cunningham
- Department of Biochemistry, University of Utah, Salt Lake City, United States
| | - Peng Wei
- Department of Biochemistry, University of Utah, Salt Lake City, United States
| | - Heather R Keys
- Whitehead Institute for Biomedical Research, Cambridge, United States
| | - Jordan Berg
- Department of Biochemistry, University of Utah, Salt Lake City, United States
| | - Alex Bott
- Department of Biochemistry, University of Utah, Salt Lake City, United States
| | - Tarun Yadav
- Department of Biochemistry, University of Utah, Salt Lake City, United States
| | - Jeremy Ryan
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, United States
| | - Deepika Sirohi
- University of Utah and ARUP Laboratories, Salt Lake City, United States
| | - Sheryl R Tripp
- University of Utah and ARUP Laboratories, Salt Lake City, United States
| | - Paige Barta
- Department of Biochemistry, University of Utah, Salt Lake City, United States
| | - Neeraj Agarwal
- Huntsman Cancer Institute, University of Utah, Salt Lake City, United States
| | - Anthony Letai
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, United States
| | - David M Sabatini
- Department of Biology, Massachusetts Institute of Technology, Cambridge, United States
| | - Matthew L Wohlever
- Department of Chemistry & Biochemistry, University of Toledo, Toledo, United States
| | - Jared Rutter
- Department of Biochemistry, University of Utah, Salt Lake City, United States.,Huntsman Cancer Institute, University of Utah, Salt Lake City, United States.,Howard Hughes Medical Institute, Salt Lake City, United States
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2
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Efentakis P, Andreadou I, Iliodromitis KE, Triposkiadis F, Ferdinandy P, Schulz R, Iliodromitis EK. Myocardial Protection and Current Cancer Therapy: Two Opposite Targets with Inevitable Cost. Int J Mol Sci 2022; 23:ijms232214121. [PMID: 36430599 PMCID: PMC9696420 DOI: 10.3390/ijms232214121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/10/2022] [Accepted: 11/12/2022] [Indexed: 11/17/2022] Open
Abstract
Myocardial protection against ischemia/reperfusion injury (IRI) is mediated by various ligands, activating different cellular signaling cascades. These include classical cytosolic mediators such as cyclic-GMP (c-GMP), various kinases such as Phosphatydilinositol-3- (PI3K), Protein Kinase B (Akt), Mitogen-Activated-Protein- (MAPK) and AMP-activated (AMPK) kinases, transcription factors such as signal transducer and activator of transcription 3 (STAT3) and bioactive molecules such as vascular endothelial growth factor (VEGF). Most of the aforementioned signaling molecules constitute targets of anticancer therapy; as they are also involved in carcinogenesis, most of the current anti-neoplastic drugs lead to concomitant weakening or even complete abrogation of myocardial cell tolerance to ischemic or oxidative stress. Furthermore, many anti-neoplastic drugs may directly induce cardiotoxicity via their pharmacological effects, or indirectly via their cardiovascular side effects. The combination of direct drug cardiotoxicity, indirect cardiovascular side effects and neutralization of the cardioprotective defense mechanisms of the heart by prolonged cancer treatment may induce long-term ventricular dysfunction, or even clinically manifested heart failure. We present a narrative review of three therapeutic interventions, namely VEGF, proteasome and Immune Checkpoint inhibitors, having opposing effects on the same intracellular signal cascades thereby affecting the heart. Moreover, we herein comment on the current guidelines for managing cardiotoxicity in the clinical setting and on the role of cardiovascular confounders in cardiotoxicity.
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Affiliation(s)
- Panagiotis Efentakis
- Laboratory of Pharmacology, Faculty of Pharmacy, National and Kapodistrian University of Athens, 15771 Athens, Greece
| | - Ioanna Andreadou
- Laboratory of Pharmacology, Faculty of Pharmacy, National and Kapodistrian University of Athens, 15771 Athens, Greece
- Correspondence: ; Tel.: +30-210-727-4827; Fax: +30-210-727-4747
| | | | | | - Péter Ferdinandy
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, 1089 Budapest, Hungary
- Pharmahungary Group, 6722 Szeged, Hungary
| | - Rainer Schulz
- Institute of Physiology, Justus Liebig University Giessen, 35390 Giessen, Germany
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Burt P, Cornelis R, Geißler G, Hahne S, Radbruch A, Chang HD, Thurley K. Data-Driven Mathematical Model of Apoptosis Regulation in Memory Plasma Cells. Cells 2022; 11:cells11091547. [PMID: 35563853 PMCID: PMC9102437 DOI: 10.3390/cells11091547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/13/2022] [Accepted: 04/21/2022] [Indexed: 12/04/2022] Open
Abstract
Memory plasma cells constitutively produce copious amounts of antibodies, imposing a critical risk factor for autoimmune disease. We previously found that plasma cell survival requires secreted factors such as APRIL and direct contact to stromal cells, which act in concert to activate NF-κB- and PI3K-dependent signaling pathways to prevent cell death. However, the regulatory properties of the underlying biochemical network are confounded by the complexity of potential interaction and cross-regulation pathways. Here, based on flow-cytometric quantification of key signaling proteins in the presence or absence of the survival signals APRIL and contact to the stromal cell line ST2, we generated a quantitative model of plasma cell survival. Our model emphasizes the non-redundant nature of the two plasma cell survival signals APRIL and stromal cell contact, and highlights a requirement for differential regulation of individual caspases. The modeling approach allowed us to unify distinct data sets and derive a consistent picture of the intertwined signaling and apoptosis pathways regulating plasma cell survival.
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Affiliation(s)
- Philipp Burt
- German Rheumatism Research Center, 10117 Berlin, Germany; (P.B.); (R.C.); (G.G.); (S.H.); (A.R.)
- Institute for Theoretical Biology, Humboldt University, 10115 Berlin, Germany
| | - Rebecca Cornelis
- German Rheumatism Research Center, 10117 Berlin, Germany; (P.B.); (R.C.); (G.G.); (S.H.); (A.R.)
| | - Gustav Geißler
- German Rheumatism Research Center, 10117 Berlin, Germany; (P.B.); (R.C.); (G.G.); (S.H.); (A.R.)
- Institute for Theoretical Biology, Humboldt University, 10115 Berlin, Germany
| | - Stefanie Hahne
- German Rheumatism Research Center, 10117 Berlin, Germany; (P.B.); (R.C.); (G.G.); (S.H.); (A.R.)
| | - Andreas Radbruch
- German Rheumatism Research Center, 10117 Berlin, Germany; (P.B.); (R.C.); (G.G.); (S.H.); (A.R.)
| | - Hyun-Dong Chang
- German Rheumatism Research Center, 10117 Berlin, Germany; (P.B.); (R.C.); (G.G.); (S.H.); (A.R.)
- Institute of Biotechnology, Department of Cytometry, Technische Universität, 10623 Berlin, Germany
- Correspondence: (H.-D.C.); (K.T.)
| | - Kevin Thurley
- German Rheumatism Research Center, 10117 Berlin, Germany; (P.B.); (R.C.); (G.G.); (S.H.); (A.R.)
- Institute for Theoretical Biology, Humboldt University, 10115 Berlin, Germany
- Biomathematics Division, Institute of Experimental Oncology, University Hospital Bonn, 53127 Bonn, Germany
- Correspondence: (H.-D.C.); (K.T.)
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4
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Ostrowski RP, Pucko E, Matyja E. Proteasome and Neuroprotective Effect of Hyperbaric Oxygen Preconditioning in Experimental Global Cerebral Ischemia in Rats. Front Neurol 2022; 13:812581. [PMID: 35250819 PMCID: PMC8891759 DOI: 10.3389/fneur.2022.812581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 01/11/2022] [Indexed: 11/27/2022] Open
Abstract
Objectives We investigated the involvement of the proteasome in the mechanism of preconditioning with hyperbaric oxygen (HBO-PC). Methods The experiments were performed on male Wistar rats subjected to a transient global cerebral ischemia of 5 min duration (2-vessel occlusion model) and preconditioned or not with HBO for 5 preceding days (1 h HBO at 2.5 atmosphere absolute [ATA] daily). In subgroups of preconditioned rats, the proteasome inhibitor MG132 was administered 30 min prior to each preconditioning session. Twenty-four hours and 7 days post-ischemia, after neurobehavioral assessment, the brains were collected and evaluated for morphological changes and quantitative immunohistochemistry of cell markers and apoptosis-related proteins. Results We observed reduced damage of CA1 pyramidal cells in the HBO preconditioned group only at 7 days post-ischemia. However, both at early (24 h) and later (7 days) time points, HBO-PC enhanced the tissue expression of 20S core particle of the proteasome and of the nestin, diminished astroglial reactivity, and reduced p53, rabbit anti-p53 upregulated modulator of apoptosis (PUMA), and rabbit anti-B cell lymphoma-2 interacting mediator of cell death (Bim) expressions in the hippocampus and cerebral cortex. HBO-PC also improved T-maze performance at 7 days. Proteasome inhibitor abolished the beneficial effects of HBO-PC on post-ischemic neuronal injury and functional impairment and reduced the ischemic alterations in the expression of investigated proteins. Significance Preconditioning with hyperbaric oxygen-induced brain protection against severe ischemic brain insult appears to involve the proteasome, which can be linked to a depletion of apoptotic proteins and improved regenerative potential.
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O’Farrell AC, Jarzabek MA, Lindner AU, Carberry S, Conroy E, Miller IS, Connor K, Shiels L, Zanella ER, Lucantoni F, Lafferty A, White K, Meyer Villamandos M, Dicker P, Gallagher WM, Keek SA, Sanduleanu S, Lambin P, Woodruff HC, Bertotti A, Trusolino L, Byrne AT, Prehn JHM. Implementing Systems Modelling and Molecular Imaging to Predict the Efficacy of BCL-2 Inhibition in Colorectal Cancer Patient-Derived Xenograft Models. Cancers (Basel) 2020; 12:cancers12102978. [PMID: 33066609 PMCID: PMC7602510 DOI: 10.3390/cancers12102978] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 10/09/2020] [Indexed: 12/24/2022] Open
Abstract
Resistance to chemotherapy often results from dysfunctional apoptosis, however multiple proteins with overlapping functions regulate this pathway. We sought to determine whether an extensively validated, deterministic apoptosis systems model, 'DR_MOMP', could be used as a stratification tool for the apoptosis sensitiser and BCL-2 antagonist, ABT-199 in patient-derived xenograft (PDX) models of colorectal cancer (CRC). Through quantitative profiling of BCL-2 family proteins, we identified two PDX models which were predicted by DR_MOMP to be sufficiently sensitive to 5-fluorouracil (5-FU)-based chemotherapy (CRC0344), or less responsive to chemotherapy but sensitised by ABT-199 (CRC0076). Treatment with ABT-199 significantly improved responses of CRC0076 PDXs to 5-FU-based chemotherapy, but showed no sensitisation in CRC0344 PDXs, as predicted from systems modelling. 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) scans were performed to investigate possible early biomarkers of response. In CRC0076, a significant post-treatment decrease in mean standard uptake value was indeed evident only in the combination treatment group. Radiomic CT feature analysis of pre-treatment images in CRC0076 and CRC0344 PDXs identified features which could phenotypically discriminate between models, but were not predictive of treatment responses. Collectively our data indicate that systems modelling may identify metastatic (m)CRC patients benefitting from ABT-199, and that 18F-FDG-PET could independently support such predictions.
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Affiliation(s)
- Alice C. O’Farrell
- Precision Cancer Medicine Group, Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.C.O.); (M.A.J.); (I.S.M.); (K.C.); (L.S.); (A.L.); (K.W.); (A.T.B.)
| | - Monika A. Jarzabek
- Precision Cancer Medicine Group, Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.C.O.); (M.A.J.); (I.S.M.); (K.C.); (L.S.); (A.L.); (K.W.); (A.T.B.)
| | - Andreas U. Lindner
- Department of Physiology and Medical Physics, Centre for Systems Medicine, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.U.L.); (S.C.); (F.L.); (M.M.V.)
| | - Steven Carberry
- Department of Physiology and Medical Physics, Centre for Systems Medicine, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.U.L.); (S.C.); (F.L.); (M.M.V.)
| | - Emer Conroy
- UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Belfield, D04 V1W8 Dublin, Ireland; (E.C.); (W.M.G.)
| | - Ian S. Miller
- Precision Cancer Medicine Group, Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.C.O.); (M.A.J.); (I.S.M.); (K.C.); (L.S.); (A.L.); (K.W.); (A.T.B.)
| | - Kate Connor
- Precision Cancer Medicine Group, Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.C.O.); (M.A.J.); (I.S.M.); (K.C.); (L.S.); (A.L.); (K.W.); (A.T.B.)
| | - Liam Shiels
- Precision Cancer Medicine Group, Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.C.O.); (M.A.J.); (I.S.M.); (K.C.); (L.S.); (A.L.); (K.W.); (A.T.B.)
| | - Eugenia R. Zanella
- Candiolo Cancer Institute—FPO IRCCS, Candiolo, 10060 Torino, Italy; (E.R.Z.); (A.B.); (L.T.)
- Department of Oncology, University of Torino, Candiolo, 10060 Torino, Italy
| | - Federico Lucantoni
- Department of Physiology and Medical Physics, Centre for Systems Medicine, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.U.L.); (S.C.); (F.L.); (M.M.V.)
| | - Adam Lafferty
- Precision Cancer Medicine Group, Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.C.O.); (M.A.J.); (I.S.M.); (K.C.); (L.S.); (A.L.); (K.W.); (A.T.B.)
| | - Kieron White
- Precision Cancer Medicine Group, Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.C.O.); (M.A.J.); (I.S.M.); (K.C.); (L.S.); (A.L.); (K.W.); (A.T.B.)
| | - Mariangela Meyer Villamandos
- Department of Physiology and Medical Physics, Centre for Systems Medicine, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.U.L.); (S.C.); (F.L.); (M.M.V.)
| | - Patrick Dicker
- Department of Epidemiology and Public Health Medicine, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland;
| | - William M. Gallagher
- UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Belfield, D04 V1W8 Dublin, Ireland; (E.C.); (W.M.G.)
| | - Simon A. Keek
- The D-Lab, Department of Precision Medicine, GROW—School for Oncology, Maastricht University, 6229 ER Maastricht, The Netherlands; (S.A.K.); (S.S.); (P.L.); (H.C.W.)
| | - Sebastian Sanduleanu
- The D-Lab, Department of Precision Medicine, GROW—School for Oncology, Maastricht University, 6229 ER Maastricht, The Netherlands; (S.A.K.); (S.S.); (P.L.); (H.C.W.)
| | - Philippe Lambin
- The D-Lab, Department of Precision Medicine, GROW—School for Oncology, Maastricht University, 6229 ER Maastricht, The Netherlands; (S.A.K.); (S.S.); (P.L.); (H.C.W.)
- Department of Radiology and Nuclear Imaging, Maastricht University Medical Center, 6229 HX Maastricht, The Netherlands
| | - Henry C. Woodruff
- The D-Lab, Department of Precision Medicine, GROW—School for Oncology, Maastricht University, 6229 ER Maastricht, The Netherlands; (S.A.K.); (S.S.); (P.L.); (H.C.W.)
- Department of Radiology and Nuclear Imaging, Maastricht University Medical Center, 6229 HX Maastricht, The Netherlands
| | - Andrea Bertotti
- Candiolo Cancer Institute—FPO IRCCS, Candiolo, 10060 Torino, Italy; (E.R.Z.); (A.B.); (L.T.)
- Department of Oncology, University of Torino, Candiolo, 10060 Torino, Italy
| | - Livio Trusolino
- Candiolo Cancer Institute—FPO IRCCS, Candiolo, 10060 Torino, Italy; (E.R.Z.); (A.B.); (L.T.)
- Department of Oncology, University of Torino, Candiolo, 10060 Torino, Italy
| | - Annette T. Byrne
- Precision Cancer Medicine Group, Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.C.O.); (M.A.J.); (I.S.M.); (K.C.); (L.S.); (A.L.); (K.W.); (A.T.B.)
- UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Belfield, D04 V1W8 Dublin, Ireland; (E.C.); (W.M.G.)
| | - Jochen H. M. Prehn
- Department of Physiology and Medical Physics, Centre for Systems Medicine, Royal College of Surgeons in Ireland, D02 YN77 Dublin, Ireland; (A.U.L.); (S.C.); (F.L.); (M.M.V.)
- Correspondence: ; Tel.: +353-1-402-2255
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Han Y, Wang S, Wang Y, Zeng S. IGF-1 Inhibits Apoptosis of Porcine Primary Granulosa Cell by Targeting Degradation of Bim EL. Int J Mol Sci 2019; 20:ijms20215356. [PMID: 31661816 PMCID: PMC6861984 DOI: 10.3390/ijms20215356] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 09/01/2019] [Accepted: 09/04/2019] [Indexed: 01/02/2023] Open
Abstract
Insulin-like growth factor-1 (IGF-1) is an intra-ovarian growth factor that plays important endocrine or paracrine roles during ovarian development. IGF-1 affects ovarian function and female fertility through reducing apoptosis of granulosa cells, yet the underlying mechanism remains poorly characterized. Here, we aimed to address these knowledge gaps using porcine primary granulosa cells and examining the anti-apoptotic mechanisms of IGF-1. IGF-1 prevented the granulosa cell from apoptosis, as shown by TUNEL and Annexin V/PI detection, and gained the anti-apoptotic index, the ratio of Bcl-2/Bax. This process was partly mediated by reducing the pro-apoptotic BimEL (Bcl-2 Interacting Mediator of Cell Death-Extra Long) protein level. Western blotting showed that IGF-1 promoted BimEL phosphorylation through activating p-ERK1/2, and that the proteasome system was responsible for degradation of phosphorylated BimEL. Meanwhile, IGF-1 enhanced the Beclin1 level and the rate of LC3 II/LC3 I, indicating that autophagy was induced by IGF-1. By blocking the proteolysis processes of both proteasome and autophagy flux with MG132 and chloroquine, respectively, the BimEL did not reduce and the phosphorylated BimEL protein accumulated, thereby indicating that both proteasome and autophagy pathways were involved in the degradation of BimEL stimulated by IGF-1. In conclusion, IGF-1 inhibited porcine primary granulosa cell apoptosis via degradation of pro-apoptotic BimEL. This study is critical for us to further understand the mechanisms of follicular survival and atresia regulated by IGF-1. Moreover, it provides a direction for the treatment of infertility caused by ovarian dysplasia, such as polycystic ovary syndrome and the improvement of assisted reproductive technology.
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Affiliation(s)
- Ying Han
- National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics, Breeding, and Reproduction of the Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
| | - Shumin Wang
- National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics, Breeding, and Reproduction of the Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
| | - Yingzheng Wang
- National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics, Breeding, and Reproduction of the Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
| | - Shenming Zeng
- National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics, Breeding, and Reproduction of the Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
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7
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Zhang X, Liu Z, Shu Q, Yuan S, Xing Z, Song J. LncRNA SNHG6 functions as a ceRNA to regulate neuronal cell apoptosis by modulating miR-181c-5p/BIM signalling in ischaemic stroke. J Cell Mol Med 2019; 23:6120-6130. [PMID: 31334597 PMCID: PMC6714173 DOI: 10.1111/jcmm.14480] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/04/2019] [Accepted: 04/28/2019] [Indexed: 12/11/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) play important roles in the pathogenesis of brain and neurodegenerative disorders. As far as we know, the functions and potential mechanisms of small nucleolar RNA host gene 6 (SNHG6) in ischaemic stroke have not been explored. This study aimed to examine the functional role of SNHG6 in the ischaemic stroke. Middle cerebral artery occlusion (MCAO) in mice and the oxygen glucose deprivation (OGD)-induced injury in neuronal cells were applied to mimic ischaemic stroke. TTC staining, quantitative real-time PCR, cell apoptosis assay, caspase-3 activity assay, Western blot, RNA immunoprecipitation and luciferase reporter assay were performed to evaluate the function and possible mechanisms of SNHG6 in the pathogenesis of ischaemic stroke. The results show that SNHG6 expression was significantly increased both OGD-induced neuronal cells and MCAO model mice. In vitro results showed that inhibition of SNHG6 increased cell viability, inhibited cell apoptosis and caspase-3 activity in OGD-induced neuronal cells. Consistently, knockdown of SNHG6 reduced brain infarct size and improved neurological scores in the MCAO mice. Mechanistic study further revealed that SNHG6 functioned as a competing endogenous RNA (ceRNA) for miR-181c-5p, which in turn repressed its downstream target of Bcl-2 interacting mediator of cell death (BIM) and inhibiting cell apoptosis. This study revealed a novel function of SNHG6 in the modulating neuronal apoptosis in the ischaemic stroke model, and the role of SNHG6 in the regulating of neuronal apoptosis was at least partly via targeting miR-181c-5p/BIM signalling pathway.
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Affiliation(s)
- Xi'an Zhang
- Department of NeurosurgeryThe First Affiliated Hospital of Xi'an Jiaotong UniversityXi'anChina
- Department of NeurosurgeryThe Ninth Hospital of Xi'anXi'anChina
| | - Zhanhui Liu
- Department of NeurosurgeryThe Ninth Hospital of Xi'anXi'anChina
| | - Qing Shu
- Department of PharmacyThe Ninth Hospital of Xi'anXi'anChina
| | - Shanqi Yuan
- Department of NeurosurgeryThe Ninth Hospital of Xi'anXi'anChina
| | - Zhiguo Xing
- Department of NeurosurgeryThe First Affiliated Hospital of Xi'an Jiaotong UniversityXi'anChina
| | - Jinning Song
- Department of NeurosurgeryThe First Affiliated Hospital of Xi'an Jiaotong UniversityXi'anChina
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8
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Faghir-Ghanesefat H, Keshavarz-Bahaghighat H, Rajai N, Mokhtari T, Bahramnejad E, Kazemi Roodsari S, Dehpour AR. The Possible Role of Nitric Oxide Pathway in Pentylenetetrazole Preconditioning Against Seizure in Mice. J Mol Neurosci 2019; 67:477-483. [PMID: 30627955 DOI: 10.1007/s12031-018-1256-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 12/28/2018] [Indexed: 11/24/2022]
Abstract
Preconditioning is defined as an induction of adaptive response in organs against lethal stimulation provoked by subsequent mild sublethal stress. Several chemical agents have been demonstrated to cause brain tolerance through preconditioning. The aim of the present study is to test the hypothesis that preconditioning with pentylenetetrazole (PTZ) may have protective effect against seizure induced by i.v. infusion of PTZ. Mice were preconditioned by low-dose administration of PTZ (25 mg/kg) for 5 consecutive days, and the threshold of seizure elicited by i.v. infusion of PTZ was measured. To investigate the possible role of nitric oxide, NOS inhibitor enzymes, including L-NG-nitro-L-arginine methyl ester hydrochloride (L-NAME) (10 mg/kg), aminoguanidine (AG) (50 mg/kg), 7-nitroindazole (7-NI) (15 mg/kg), and L-arginine (L-arg) (60 mg/kg), were administered concomitantly with PTZ in both acute and chronic phases. Determination of seizure threshold revealed significant enhancement after preconditioning with low dose of PTZ. While the protective effect of PTZ preconditioning was enhanced after the administration of L-arg, it was reversed following administration of L-NAME and 7NI, suggesting the involvement of nitric oxide pathway as an underlying mechanism of PTZ-induced preconditioning. Preconditioning with PTZ led to brain tolerance and adaptive response in animal model of PTZ-induced seizure. This effect is in part due to the involvement of nitric oxide pathway.
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Affiliation(s)
- Hedyeh Faghir-Ghanesefat
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O. Box 13145-784, Tehran, Iran.,Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Hedieh Keshavarz-Bahaghighat
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O. Box 13145-784, Tehran, Iran.,Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Nazanin Rajai
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O. Box 13145-784, Tehran, Iran.,Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Tahmineh Mokhtari
- Nervous System Stem Cells Research Center, Semnan University of Medical Sciences, Semnan, Iran.,Department of Anatomy, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran
| | - Erfan Bahramnejad
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O. Box 13145-784, Tehran, Iran.,Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Soheil Kazemi Roodsari
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O. Box 13145-784, Tehran, Iran.,Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Reza Dehpour
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O. Box 13145-784, Tehran, Iran. .,Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran.
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9
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Wang Z, Yang W. Impaired capacity to restore proteostasis in the aged brain after ischemia: Implications for translational brain ischemia research. Neurochem Int 2018; 127:87-93. [PMID: 30599146 DOI: 10.1016/j.neuint.2018.12.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/28/2018] [Accepted: 12/28/2018] [Indexed: 12/15/2022]
Abstract
Brain ischemia induced by cardiac arrest or ischemic stroke is a severe form of metabolic stress that substantially disrupts cellular homeostasis, especially protein homeostasis (proteostasis). As proteostasis is fundamental for cellular and organismal health, cells have developed a complex network to restore proteostasis impaired by stress. Many components of this network - including ubiquitination, small ubiquitin-like modifier (SUMO) conjugation, autophagy, and the unfolded protein response (UPR) - are activated in the post-ischemic brain, and play a crucial role in cell survival and recovery of neurologic function. Importantly, recent studies have shown that ischemia-induced activation of these proteostasis-related pathways in the aged brain is impaired, indicating an aging-related decline in the self-healing capacity of the brain. This impaired capacity is a significant factor for consideration in the field of brain ischemia because the vast majority of cardiac arrest and stroke patients are elderly. In this review, we focus on the effects of aging on these critical proteostasis-related pathways in the brain, and discuss their implications in translational brain ischemia research.
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Affiliation(s)
- Zhuoran Wang
- Center for Perioperative Organ Protection, Department of Anesthesiology, Duke University Medical Center, Durham, NC, USA
| | - Wei Yang
- Center for Perioperative Organ Protection, Department of Anesthesiology, Duke University Medical Center, Durham, NC, USA.
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10
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Li XQ, Yu Q, Tan WF, Zhang ZL, Ma H. MicroRNA-125b mimic inhibits ischemia reperfusion-induced neuroinflammation and aberrant p53 apoptotic signalling activation through targeting TP53INP1. Brain Behav Immun 2018; 74:154-165. [PMID: 30193876 DOI: 10.1016/j.bbi.2018.09.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 08/23/2018] [Accepted: 09/03/2018] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Ischemia reperfusion (IR) injury affects neuronal function through multiple pathogeneses that induce neuroinflammation and cellular apoptosis. The important roles of microRNAs (miRs) in the regulation of spinal cord IR have been recently reported. Among these roles, we investigated whether miR-125b and its downstream targets regulated the p53 signalling network and participated in both inflammation and apoptosis. METHODS An IR model was established via 12-min occlusion of the aortic arch. The direct interaction between miR-125b and TP53INP1 was demonstrated by Western blotting and luciferase assays. The cellular distributions of TP53INP1 were visualised by double immunofluorescence labelling. The effects of miR-125b on the expression of TP53INP1, p53 and release of proinflammatory cytokines were evaluated by synthetic miRs. Additionally, the detection of hind-limb motor function in vivo and motor neuronal apoptosis in vitro were evaluated to explore the potential mechanisms. RESULTS IR-induced alterations in hind-limb motor function were closely related to the temporal changes in miR-125b and TP53INP1 expression. The miR-125b/TP53INP1 gene pair was confirmed by luciferase assay. Compared with Sham controls, IR treatment resulted in increased TP53INP1 immunoreactivity that was primarily distributed in neurons. Treatment with miR-125b mimic markedly decreased the protein levels of TP53INP1, p53 and cytokines interleukin (IL)-1β and tumour necrosis factor (TNF)-α, whereas miR-125b control or inhibitor did not have the above-mentioned effects. Moreover, miR-125b mimic improved motor function in vivo and attenuated neuronal apoptosis in vitro, as demonstrated by the increased average Tarlov scores in lower limbs and lower percentages of neurons in the A4 and A2 quadrants of flow cytometry. Fluorescent staining and quantification further indicated that miR-125b mimic decreased the immunoreactivities of p53 and cleaved caspase 3 in neurons and simultaneously reduced the number of double-labelled cells with TP53INP1. CONCLUSIONS miR-125b mimic partially protected neurons against neuroinflammation and aberrant p53 network activation-induced apoptosis during IR injury through downregulation of TP53INP1.
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Affiliation(s)
- Xiao-Qian Li
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang 110001, Liaoning, China
| | - Qian Yu
- Department of Thoracic Surgery, Fourth Affiliated Hospital, China Medical University, Shenyang 110032, Liaoning, China
| | - Wen-Fei Tan
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang 110001, Liaoning, China
| | - Zai-Li Zhang
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang 110001, Liaoning, China
| | - Hong Ma
- Department of Anesthesiology, First Affiliated Hospital, China Medical University, Shenyang 110001, Liaoning, China.
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11
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Lv P, Wang W, Cao Z, Zhao D, Zhao G, Li D, Qi L, Xu J. Fsk and IBMX inhibit proliferation and proapoptotic of glioma stem cells via activation of cAMP signaling pathway. J Cell Biochem 2018; 120:321-331. [PMID: 30171713 DOI: 10.1002/jcb.27364] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 06/26/2018] [Indexed: 12/14/2022]
Abstract
OBJECTIVE We aimed to find out the underlying mechanism of forskolin (Fsk) and 3-isobutyl-1-methylxanthine (IBMX) on glioma stem cells (GSCs). METHODS The expression of cAMP-related protein CREB and pCREB as well as apoptosis-related proteins were detected through Western blot analysis. The level of proliferation and growth rate of human GSCs was measured through thiazolyl blue tetrazolium bromide assay and stem cells forming sphere assay. The apoptosis-related gene expression was measured through reverse transcription-polymerase chain reaction. RESULTS cAMP signaling pathway was activated in GSCs with Fsk-IBMX administration. Fsk-IBMX could inhibit the proliferation as well as invasion and promote the apoptosis of U87 cells. Besides, U0126 could inhibit MAPK signaling pathway to increase the sensitivity of GSCs to cAMP signaling pathway. As a result, Fsk-IBMX combined with U0126 had more negative effect on GSCs. CONCLUSIONS The relationship of cAMP and MAPK signaling pathway in GSCs may provide a potential therapeutic strategy in glioma.
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Affiliation(s)
- Peng Lv
- Department of Pathophysiology, Jilin Medical University, Jilin, China
| | - Weiyao Wang
- Department of Pathophysiology, Jilin Medical University, Jilin, China
| | - Zhiyou Cao
- 465 Hospital, Jilin Medical University, Jilin, China
| | - Donghai Zhao
- Department of Pathology, Jilin Medical University, Jilin, China
| | - Guifang Zhao
- Department of Pathology, Jilin Medical University, Jilin, China
| | - Dailin Li
- Institute of Petrochemical Technology, Jilin Institute of Chemical Technology, Jilin, China
| | - Ling Qi
- Department of Pathophysiology, Jilin Medical University, Jilin, China
| | - Junjie Xu
- School of Basic Medicine Sciences, Jilin Medical University, Jilin, China
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12
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Han MA, Min KJ, Woo SM, Seo BR, Kwon TK. Eupafolin enhances TRAIL-mediated apoptosis through cathepsin S-induced down-regulation of Mcl-1 expression and AMPK-mediated Bim up-regulation in renal carcinoma Caki cells. Oncotarget 2018; 7:65707-65720. [PMID: 27582546 PMCID: PMC5323186 DOI: 10.18632/oncotarget.11604] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 08/13/2016] [Indexed: 12/21/2022] Open
Abstract
Eupafolin, a flavone found in Artemisia princeps, has been reported for its anti-tumor activity in several cancer cells. In this study, we examined whether eupafolin could sensitize TRAIL-mediated apoptosis in human renal carcinoma Caki cells. We found that eupafolin alone and TRAIL alone had no effect on apoptosis. However, combined treatment with eupafolin and TRAIL markedly induced apoptosis in human renal carcinoma (Caki) cells, glioma cells (U251MG), and prostate cancer cells (DU145), but not normal cells [mesangial cells (MC) and normal mouse kidney cells (TCMK-1)]. Eupafolin induced down-regulation of Mcl-1 expression at the post-translational levels in cathepsin S-dependent manner, and over-expression of Mcl-1 markedly blocked apoptosis induced by combined treatment with eupafolin and TRAIL. In addition, eupafolin increased Bim expression at the post-translational levels via AMP-activated protein kinase (AMPK)-mediated inhibition of proteasome activity. Knock-down of Bim expression by siRNA inhibited eupafolin plus TRAIL-induced apoptosis. Furthermore, combined treatment with eupafolin and TRAIL reduced tumor growth in xenograft models. Taken together, these results suggest that eupafolin enhanced TRAIL-mediated apoptosis via down-regulation of Mcl-1 and up-regulation of Bim in renal carcinoma Caki cells.
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Affiliation(s)
- Min Ae Han
- Department of Immunology, School of Medicine, Keimyung University, Dalseo-Gu, Daegu 704-701, South Korea
| | - Kyoung-Jin Min
- Department of Immunology, School of Medicine, Keimyung University, Dalseo-Gu, Daegu 704-701, South Korea
| | - Seon Min Woo
- Department of Immunology, School of Medicine, Keimyung University, Dalseo-Gu, Daegu 704-701, South Korea
| | - Bo Ram Seo
- Department of Immunology, School of Medicine, Keimyung University, Dalseo-Gu, Daegu 704-701, South Korea
| | - Taeg Kyu Kwon
- Department of Immunology, School of Medicine, Keimyung University, Dalseo-Gu, Daegu 704-701, South Korea
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13
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Gupta I, Singh K, Varshney NK, Khan S. Delineating Crosstalk Mechanisms of the Ubiquitin Proteasome System That Regulate Apoptosis. Front Cell Dev Biol 2018; 6:11. [PMID: 29479529 PMCID: PMC5811474 DOI: 10.3389/fcell.2018.00011] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 01/26/2018] [Indexed: 01/10/2023] Open
Abstract
Regulatory functions of the ubiquitin-proteasome system (UPS) are exercised mainly by the ubiquitin ligases and deubiquitinating enzymes. Degradation of apoptotic proteins by UPS is central to the maintenance of cell health, and deregulation of this process is associated with several diseases including tumors, neurodegenerative disorders, diabetes, and inflammation. Therefore, it is the view that interrogating protein turnover in cells can offer a strategy for delineating disease-causing mechanistic perturbations and facilitate identification of drug targets. In this review, we are summarizing an overview to elucidate the updated knowledge on the molecular interplay between the apoptosis and UPS pathways. We have condensed around 100 enzymes of UPS machinery from the literature that ubiquitinates or deubiquitinates the apoptotic proteins and regulates the cell fate. We have also provided a detailed insight into how the UPS proteins are able to fine-tune the intrinsic, extrinsic, and p53-mediated apoptotic pathways to regulate cell survival or cell death. This review provides a comprehensive overview of the potential of UPS players as a drug target for cancer and other human disorders.
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Affiliation(s)
- Ishita Gupta
- Structural Immunology Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, India.,Drug Discovery Research Centre, Translational Health Science and Technology Institute, Faridabad, India
| | - Kanika Singh
- Drug Discovery Research Centre, Translational Health Science and Technology Institute, Faridabad, India
| | - Nishant K Varshney
- Drug Discovery Research Centre, Translational Health Science and Technology Institute, Faridabad, India
| | - Sameena Khan
- Drug Discovery Research Centre, Translational Health Science and Technology Institute, Faridabad, India
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14
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Gao X, Liu Y, Xie Y, Wang Y, Qi S. Remote ischemic postconditioning confers neuroprotective effects via inhibition of the BID-mediated mitochondrial apoptotic pathway. Mol Med Rep 2017; 16:515-522. [PMID: 28560462 PMCID: PMC5482128 DOI: 10.3892/mmr.2017.6652] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 02/15/2017] [Indexed: 11/25/2022] Open
Abstract
Ischemic postconditioning has been demonstrated to alleviate brain ischemia/reperfusion-induced neuronal apoptosis; however, the protective mechanisms underlying the improved and more convenient method of remote ischemic postconditioning (RIPostC) are only recently beginning to be elucidated. Mitochondria are important in the regulation of cell apoptosis, and the B-cell lymphoma 2 (Bcl-2) homology 3 interacting-domain death agonist (BID) promotes the insertion/oligomerization of Bcl-2-associated X protein into the mitochondrial outer membrane, leading to the release of proapoptotic proteins from the mitochondria. The present study hypothesized that RIPostC targets the BID-mediated mitochondrial apoptotic pathway to exert neuroprotective effects, and the optimal time window for RIPostC application was investigated. RIPostC was conducted as follows: Three 10-min cycles of bilateral femoral artery occlusion with intervals of 10 min reperfusion after 0, 10 or 30 min of brain reperfusion. The results revealed that reperfusion induced significant activation of BID, via proteolytic cleavage and translocation to the mitochondria, as determined using western blot analysis and immunofluorescence staining. Mitochondrial release of cytochrome c was additionally detected during BID activation, all of which were inhibited by the application of RIPostC. When RIPostC was applied during reperfusion, it demonstrated a significant protective effect. Furthermore, the infarct volume, neurological function and the degree of neuronal apoptosis were improved with application of RIPostC. These results suggested that the protective mechanisms of RIPostC may be associated with inhibition of the BID-mediated mitochondrial apoptotic pathway, which may act as a potential molecular target for therapeutic intervention in the future.
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Affiliation(s)
- Xiaoying Gao
- Department of Anesthesiology, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Yun Liu
- Department of Anesthesiology, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Yuying Xie
- Department of Anesthesiology, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Ying Wang
- Department of Anesthesiology, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
| | - Sihua Qi
- Department of Anesthesiology, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China
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15
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Lai X, Friedman A. Exosomal microRNA concentrations in colorectal cancer: A mathematical model. J Theor Biol 2017; 415:70-83. [DOI: 10.1016/j.jtbi.2016.12.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 12/06/2016] [Accepted: 12/10/2016] [Indexed: 12/19/2022]
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16
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Sensitivity of GBM cells to cAMP agonist-mediated apoptosis correlates with CD44 expression and agonist resistance with MAPK signaling. Cell Death Dis 2016; 7:e2494. [PMID: 27906173 PMCID: PMC5261024 DOI: 10.1038/cddis.2016.393] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 10/25/2016] [Accepted: 10/26/2016] [Indexed: 02/07/2023]
Abstract
In some cell types, activation of the second messenger cAMP leads to increased expression of proapoptotic Bim and subsequent cell death. We demonstrate that suppression of the cAMP pathway is a common event across many cancers and that pharmacological activation of cAMP in glioblastoma (GBM) cells leads to enhanced BIM expression and apoptosis in specific GBM cell types. We identified the MAPK signaling axis as the determinant of cAMP agonist sensitivity in GBM cells, with high MAPK activity corresponding to cAMP resistance and low activity corresponding to sensitization to cAMP-induced apoptosis. Sensitive cells were efficiently killed by cAMP agonists alone, while targeting both the cAMP and MAPK pathways in resistant GBM cells resulted in efficient apoptosis. We also show that CD44 is differentially expressed in cAMP agonist-sensitive and -resistant cells. We thus propose that CD44 may be a useful biomarker for distinguishing tumors that may be sensitive to cAMP agonists alone or cAMP agonists in combination with other pathway inhibitors. This suggests that using existing chemotherapeutic compounds in combination with existing FDA-approved cAMP agonists may fast track trials toward improved therapies for difficult-to-treat cancers, such as GBM.
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17
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Mollereau B, Rzechorzek NM, Roussel BD, Sedru M, Van den Brink DM, Bailly-Maitre B, Palladino F, Medinas DB, Domingos PM, Hunot S, Chandran S, Birman S, Baron T, Vivien D, Duarte CB, Ryoo HD, Steller H, Urano F, Chevet E, Kroemer G, Ciechanover A, Calabrese EJ, Kaufman RJ, Hetz C. Adaptive preconditioning in neurological diseases - therapeutic insights from proteostatic perturbations. Brain Res 2016; 1648:603-616. [PMID: 26923166 PMCID: PMC5010532 DOI: 10.1016/j.brainres.2016.02.033] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 02/16/2016] [Indexed: 02/06/2023]
Abstract
In neurological disorders, both acute and chronic neural stress can disrupt cellular proteostasis, resulting in the generation of pathological protein. However in most cases, neurons adapt to these proteostatic perturbations by activating a range of cellular protective and repair responses, thus maintaining cell function. These interconnected adaptive mechanisms comprise a 'proteostasis network' and include the unfolded protein response, the ubiquitin proteasome system and autophagy. Interestingly, several recent studies have shown that these adaptive responses can be stimulated by preconditioning treatments, which confer resistance to a subsequent toxic challenge - the phenomenon known as hormesis. In this review we discuss the impact of adaptive stress responses stimulated in diverse human neuropathologies including Parkinson׳s disease, Wolfram syndrome, brain ischemia, and brain cancer. Further, we examine how these responses and the molecular pathways they recruit might be exploited for therapeutic gain. This article is part of a Special Issue entitled SI:ER stress.
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Affiliation(s)
- B Mollereau
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France.
| | - N M Rzechorzek
- Centre for Clinical Brain Sciences, Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, United Kingdom; Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Roslin, Midlothian EH25 9RG, United Kingdom
| | - B D Roussel
- Inserm, UMR-S U919 Serine Proteases and Pathophysiology of the Neurovascular Unit, 14000 Caen, France
| | - M Sedru
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France
| | - D M Van den Brink
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France
| | - B Bailly-Maitre
- INSERM U1065, C3M, Team 8 (Hepatic Complications in Obesity), Nice, France
| | - F Palladino
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France
| | - D B Medinas
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Center for Molecular Studies of the Cell, Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile; Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Santiago, Chile
| | - P M Domingos
- ITQB-UNL, Av. da Republica, EAN, 2780-157 Oeiras, Portugal
| | - S Hunot
- Inserm, U 1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - S Chandran
- Centre for Clinical Brain Sciences, Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, United Kingdom
| | - S Birman
- Genes Circuits Rhythms and Neuropathology, Brain Plasticity Unit, CNRS UMR 8249, ESPCI ParisTech, PSL Research University, 75005 Paris, France
| | - T Baron
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Neurodegenerative Diseases Unit, 31, avenue Tony Garnier, 69364 Lyon Cedex 07, France
| | - D Vivien
- Inserm, UMR-S U919 Serine Proteases and Pathophysiology of the Neurovascular Unit, 14000 Caen, France
| | - C B Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Faculty of Medicine, Rua Larga, and Department of Life Sciences, University of Coimbra, 3004-504 Coimbra, Portugal
| | - H D Ryoo
- Department of Cell Biology, New York University School of Medicine, New York, NY, USA
| | - H Steller
- Howard Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
| | - F Urano
- Washington University School of Medicine, Department of Internal Medicine, St. Louis, MO 63110 USA
| | - E Chevet
- Inserm ERL440 "Oncogenesis, Stress, Signaling", Université de Rennes 1, Rennes, France; Centre de Lutte Contre le Cancer Eugène Marquis, Rennes, France
| | - G Kroemer
- Equipe 11 labellisée par la Ligue contre le Cancer, Centre de Recherche des Cordeliers, Paris, France; Cell Biology and Metabolomics platforms, Gustave Roussy Comprehensive Cancer Center, Villejuif, France; INSERM, U1138, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie, Paris, France; Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France; Karolinska Institute, Department of Women׳s and Children׳s Health, Karolinska University Hospital, Stockholm, Sweden
| | - A Ciechanover
- The Polak Cancer and Vascular Biology Research Center, The Rappaport Faculty of Medicine and Research Institute, Technion-Israel Institute of Technology, Haifa 30196, Israel
| | - E J Calabrese
- Department of Environmental Health Sciences, University of Massachusetts, Morrill I, N344, Amherst, MA 01003, USA
| | - R J Kaufman
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
| | - C Hetz
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Center for Molecular Studies of the Cell, Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile; Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Santiago, Chile; Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA
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18
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Bickler P, Clark J, Gabatto P, Brosnan H. Hypoxic preconditioning and cell death from oxygen/glucose deprivation co-opt a subset of the unfolded protein response in hippocampal neurons. Neuroscience 2015; 310:306-21. [DOI: 10.1016/j.neuroscience.2015.09.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 09/02/2015] [Accepted: 09/07/2015] [Indexed: 01/04/2023]
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19
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Cuomo O, Vinciguerra A, Cerullo P, Anzilotti S, Brancaccio P, Bilo L, Scorziello A, Molinaro P, Di Renzo G, Pignataro G. Ionic homeostasis in brain conditioning. Front Neurosci 2015; 9:277. [PMID: 26321902 PMCID: PMC4530315 DOI: 10.3389/fnins.2015.00277] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/23/2015] [Indexed: 12/26/2022] Open
Abstract
Most of the current focus on developing neuroprotective therapies is aimed at preventing neuronal death. However, these approaches have not been successful despite many years of clinical trials mainly because the numerous side effects observed in humans and absent in animals used at preclinical level. Recently, the research in this field aims to overcome this problem by developing strategies which induce, mimic, or boost endogenous protective responses and thus do not interfere with physiological neurotransmission. Preconditioning is a protective strategy in which a subliminal stimulus is applied before a subsequent harmful stimulus, thus inducing a state of tolerance in which the injury inflicted by the challenge is mitigated. Tolerance may be observed in ischemia, seizure, and infection. Since it requires protein synthesis, it confers delayed and temporary neuroprotection, taking hours to develop, with a pick at 1–3 days. A new promising approach for neuroprotection derives from post-conditioning, in which neuroprotection is achieved by a modified reperfusion subsequent to a prolonged ischemic episode. Many pathways have been proposed as plausible mechanisms to explain the neuroprotection offered by preconditioning and post-conditioning. Although the mechanisms through which these two endogenous protective strategies exert their effects are not yet fully understood, recent evidence highlights that the maintenance of ionic homeostasis plays a key role in propagating these neuroprotective phenomena. The present article will review the role of protein transporters and ionic channels involved in the control of ionic homeostasis in the neuroprotective effect of ischemic preconditioning and post-conditioning in adult brain, with particular regards to the Na+/Ca2+ exchangers (NCX), the plasma membrane Ca2+-ATPase (PMCA), the Na+/H+ exchange (NHE), the Na+/K+/2Cl− cotransport (NKCC) and the acid-sensing cation channels (ASIC). Ischemic stroke is the third leading cause of death and disability. Up until now, all clinical trials testing potential stroke neuroprotectants failed. For this reason attention of researchers has been focusing on the identification of brain endogenous neuroprotective mechanisms activated after cerebral ischemia. In this context, ischemic preconditioning and ischemic post-conditioning represent two neuroprotecive strategies to investigate in order to identify new molecular target to reduce the ischemic damage.
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Affiliation(s)
- Ornella Cuomo
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples Naples, Italy
| | - Antonio Vinciguerra
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples Naples, Italy
| | - Pierpaolo Cerullo
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples Naples, Italy
| | | | - Paola Brancaccio
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples Naples, Italy
| | - Leonilda Bilo
- Division of Neurology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples Naples, Italy
| | - Antonella Scorziello
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples Naples, Italy
| | - Pasquale Molinaro
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples Naples, Italy
| | - Gianfranco Di Renzo
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples Naples, Italy
| | - Giuseppe Pignataro
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples Naples, Italy
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20
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Li D, Li X, Wu J, Li J, Zhang L, Xiong T, Tang J, Qu Y, Mu D. Involvement of the JNK/FOXO3a/Bim Pathway in Neuronal Apoptosis after Hypoxic-Ischemic Brain Damage in Neonatal Rats. PLoS One 2015; 10:e0132998. [PMID: 26171786 PMCID: PMC4501737 DOI: 10.1371/journal.pone.0132998] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 06/23/2015] [Indexed: 11/18/2022] Open
Abstract
c-Jun N-terminal kinase (JNK) plays a key role in the regulation of neuronal apoptosis. Previous studies have revealed that forkhead transcription factor (FOXO3a) is a critical effector of JNK-mediated tumor suppression. However, it is not clear whether the JNK/FOXO3a pathway is involved in neuronal apoptosis in the developing rat brain after hypoxia-ischemia (HI). In this study, we generated an HI model using postnatal day 7 rats. Fluorescence immunolabeling and Western blot assays were used to detect the distribution and expression of total and phosphorylated JNK and FOXO3a and the pro-apoptotic proteins Bim and CC3. We found that JNK phosphorylation was accompanied by FOXO3a dephosphorylation, which induced FOXO3a translocation into the nucleus, resulting in the upregulation of levels of Bim and CC3 proteins. Furthermore, we found that JNK inhibition by AS601245, a specific JNK inhibitor, significantly increased FOXO3a phosphorylation, which attenuated FOXO3a translocation into the nucleus after HI. Moreover, JNK inhibition downregulated levels of Bim and CC3 proteins, attenuated neuronal apoptosis and reduced brain infarct volume in the developing rat brain. Our findings suggest that the JNK/FOXO3a/Bim pathway is involved in neuronal apoptosis in the developing rat brain after HI. Agents targeting JNK may offer promise for rescuing neurons from HI-induced damage.
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Affiliation(s)
- Deyuan Li
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan 610041, PR China
| | - Xihong Li
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan 610041, PR China
| | - Jinlin Wu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan 610041, PR China
| | - Jinhui Li
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan 610041, PR China
| | - Li Zhang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan 610041, PR China
| | - Tao Xiong
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan 610041, PR China
| | - Jun Tang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan 610041, PR China
| | - Yi Qu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan 610041, PR China
| | - Dezhi Mu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu 610041, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, Sichuan 610041, PR China
- Department of Neurology, University of California San Francisco, San Francisco, CA 94143, United States of America
- * E-mail:
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Meller R, Pearson A, Simon RP. Dynamic changes in DNA methylation in ischemic tolerance. Front Neurol 2015; 6:102. [PMID: 26029158 PMCID: PMC4432797 DOI: 10.3389/fneur.2015.00102] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 04/24/2015] [Indexed: 01/12/2023] Open
Abstract
Epigenetic mediators of gene expression are hypothesized to regulate transcriptomic responses to preconditioning ischemia and ischemic tolerance. Here, we utilized a methyl-DNA enrichment protocol and sequencing (ChIP-seq) to identify patterns of DNA methylation in an established model of ischemic tolerance in neuronal cultures (oxygen and glucose deprivation: OGD). We observed an overall decrease in global DNA methylation at 4 h following preconditioning ischemia (30 min OGD), harmful ischemia (120 min OGD), and in ischemic tolerant neuronal cultures (30 min OGD, 24 h recovery, 120 min OGD). We detected a smaller cohort of hypermethylated regions following ischemic conditions, which were further analyzed revealing differential chromosomal localization of methylation, and a differential concentration of methylation on genomic regions. Together, these data show that the temporal profiles of DNA methylation with respect to chromatin hyper- and hypo-methylation following various ischemic conditions are highly dynamic, and may reveal novel targets for neuroprotection.
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Affiliation(s)
- Robert Meller
- Translational Stroke Program, Neuroscience Institute, Morehouse School of Medicine , Atlanta, GA , USA
| | - Andrea Pearson
- Translational Stroke Program, Neuroscience Institute, Morehouse School of Medicine , Atlanta, GA , USA
| | - Roger P Simon
- Translational Stroke Program, Neuroscience Institute, Morehouse School of Medicine , Atlanta, GA , USA ; Grady Memorial Hospital , Atlanta, GA , USA
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22
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Meller R, Simon RP. A critical review of mechanisms regulating remote preconditioning-induced brain protection. J Appl Physiol (1985) 2015; 119:1135-42. [PMID: 25953834 DOI: 10.1152/japplphysiol.00169.2015] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 05/05/2015] [Indexed: 12/31/2022] Open
Abstract
Remote preconditioning (rPC) is the phenomenon whereby brief organ ischemia evokes an endogenous response such that a different (remote) organ is protected against subsequent, normally injurious ischemia. Experiments show rPC to be effective at evoking cardioprotection against ischemic heart injury and, more recently, neuroprotection against brain ischemia. Such is the enthusiasm for rPC that human studies have been initiated. Clinical trials suggest rPC to be safe (phase II trial) and effective in reducing stroke incidence in a population with high stroke risk. However, despite the therapeutic potential of rPC, there is a large gap in knowledge regarding the effector mechanisms of rPC and how it might be orchestrated to improve outcome after stroke. Here we provide a critical review of mechanisms that are directly attributable to rPC-induced neuroprotection in preclinical trials of rPC.
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Affiliation(s)
- Robert Meller
- Translational Stroke Program, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia; and
| | - Roger P Simon
- Translational Stroke Program, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia; and Grady Memorial Hospital, Atlanta, Georgia
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A Bim-targeting strategy overcomes adaptive bortezomib resistance in myeloma through a novel link between autophagy and apoptosis. Blood 2014; 124:2687-97. [PMID: 25208888 DOI: 10.1182/blood-2014-03-564534] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Bim contributes to resistance to various standard and novel agents. Here we demonstrate that Bim plays a functional role in bortezomib resistance in multiple myeloma (MM) cells and that targeting Bim by combining histone deacetylase inhibitors (HDACIs) with BH3 mimetics (eg, ABT-737) overcomes bortezomib resistance. BH3-only protein profiling revealed high Bim levels (Bim(hi)) in most MM cell lines and primary CD138(+) MM samples. Whereas short hairpin RNA Bim knockdown conferred bortezomib resistance in Bim(hi) cells, adaptive bortezomib-resistant cells displayed marked Bim downregulation. HDACI upregulated Bim and, when combined with ABT-737, which released Bim from Bcl-2/Bcl-xL, potently killed bortezomib-resistant cells. These events were correlated with Bim-associated autophagy attenuation, whereas Bim knockdown sharply increased autophagy in Bim(hi) cells. In Bim(low) cells, autophagy disruption by chloroquine (CQ) was required for HDACI/ABT-737 to induce Bim expression and lethality. CQ also further enhanced HDACI/ABT-737 lethality in bortezomib-resistant cells. Finally, HDACI failed to diminish autophagy or potentiate ABT-737-induced apoptosis in bim(-/-) mouse embryonic fibroblasts. Thus, Bim deficiency represents a novel mechanism of adaptive bortezomib resistance in MM cells, and Bim-targeting strategies combining HDACIs (which upregulate Bim) and BH3 mimetics (which unleash Bim from antiapoptotic proteins) overcomes such resistance, in part by disabling cytoprotective autophagy.
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Dávila D, Jiménez-Mateos EM, Mooney CM, Velasco G, Henshall DC, Prehn JHM. Hsp27 binding to the 3'UTR of bim mRNA prevents neuronal death during oxidative stress-induced injury: a novel cytoprotective mechanism. Mol Biol Cell 2014; 25:3413-23. [PMID: 25187648 PMCID: PMC4214787 DOI: 10.1091/mbc.e13-08-0495] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Neurons face a changeable microenvironment and therefore need mechanisms that allow rapid switch on/off of their cytoprotective and apoptosis-inducing signaling pathways. Cellular mechanisms that control apoptosis activation include the regulation of pro/antiapoptotic mRNAs through their 3'-untranslated region (UTR). This region holds binding elements for RNA-binding proteins, which can control mRNA translation. Here we demonstrate that heat shock protein 27 (Hsp27) prevents oxidative stress-induced cell death in cerebellar granule neurons by specific regulation of the mRNA for the proapoptotic BH3-only protein, Bim. Hsp27 depletion induced by oxidative stress using hydrogen peroxide (H2O2) correlated with bim gene activation and subsequent neuronal death, whereas enhanced Hsp27 expression prevented these. This effect could not be explained by proteasomal degradation of Bim or bim promoter inhibition; however, it was associated with a specific increase in the levels of bim mRNA and with its binding to Hsp27. Finally, we determined that enhanced Hsp27 expression in neurons exposed to H2O2 or glutamate prevented the translation of a reporter plasmid where bim-3'UTR mRNA sequence was cloned downstream of a luciferase gene. These results suggest that repression of bim mRNA translation through binding to the 3'UTR constitutes a novel cytoprotective mechanism of Hsp27 during stress in neurons.
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Affiliation(s)
- David Dávila
- Department of Physiology and Medical Physics and RCSI Centre for the Study of Neurological Disorders, Royal College of Surgeons in Ireland, Dublin 2, Ireland Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, 28040 Madrid, Spain
| | - Eva M Jiménez-Mateos
- Department of Physiology and Medical Physics and RCSI Centre for the Study of Neurological Disorders, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Claire M Mooney
- Department of Physiology and Medical Physics and RCSI Centre for the Study of Neurological Disorders, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Guillermo Velasco
- Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, 28040 Madrid, Spain
| | - David C Henshall
- Department of Physiology and Medical Physics and RCSI Centre for the Study of Neurological Disorders, Royal College of Surgeons in Ireland, Dublin 2, Ireland
| | - Jochen H M Prehn
- Department of Physiology and Medical Physics and RCSI Centre for the Study of Neurological Disorders, Royal College of Surgeons in Ireland, Dublin 2, Ireland
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Tylicka M, Matuszczak E, Dębek W, Hermanowicz A, Ostrowska H. Circulating proteasome activity following mild head injury in children. Childs Nerv Syst 2014; 30:1191-6. [PMID: 24700339 PMCID: PMC4072065 DOI: 10.1007/s00381-014-2409-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 03/24/2014] [Indexed: 01/04/2023]
Abstract
PURPOSE The aim of the study is to characterize changes in circulating proteasome (c-proteasome) activity following mild traumatic brain injury in children. METHODS Fifty children managed at the Department of Pediatric Surgery because of concussion-mild head injury was randomly included into the study. The children were aged 11 months to 17 years (median = 10.07 + -1.91 years). Plasma proteasome activity was assessed using Suc-Leu-Leu-Val-Tyr-AMC peptide substrate, 2-6 h, 12-16 h, and 2 days after injury. Twenty healthy children admitted for planned inguinal hernia repair served as controls. RESULTS Statistically significant elevation of plasma c-proteasome activity was noted in children with mild head injury 2-6 h, 12-16 h, and 2 days after the injury. CONCLUSIONS Authors observed a statistically significant upward trend in the c-proteasome activity between 2-6 and 12-16 h after the mild head injury, consistent with the onset of the symptoms of cerebral concussion and a downward trend in the c-proteasome activity in the plasma of children with mild head injury between 12-16 h and on the second day after the injury, consistent with the resolving of the symptoms of cerebral concussion. Further studies are needed to demonstrate that the proteasome activity could be a prognostic factor, which can help in further diagnostic and therapeutic decisions in patients with head injury.
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Affiliation(s)
- Marzena Tylicka
- Department of Biophysics, Medical University of Białystok, Mickiewicza 2A, 15-089 Białystok, Poland
| | - Ewa Matuszczak
- Department of Pediatric Surgery, Medical University of Białystok, 15-274 Białystok, Poland
| | - Wojciech Dębek
- Department of Pediatric Surgery, Medical University of Białystok, 15-274 Białystok, Poland
| | - Adam Hermanowicz
- Department of Pediatric Surgery, Medical University of Białystok, 15-274 Białystok, Poland
| | - Halina Ostrowska
- Department of Pediatric Surgery, Medical University of Białystok, 15-274 Białystok, Poland
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Jessick VJ, Xie M, Pearson AN, Torrey DJ, Ashley MD, Thompson S, Meller R. Investigating the role of the actin regulating complex ARP2/3 in rapid ischemic tolerance induced neuro-protection. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2013; 5:216-227. [PMID: 24379906 PMCID: PMC3867699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Accepted: 10/27/2013] [Indexed: 06/03/2023]
Abstract
Neuronal morphology is highly sensitive to ischemia, although some re-organization may promote neuroprotection. In this study we investigate the role of actin regulating proteins (ARP2, ARP3 and WAVE-1) and their role in rapid ischemic tolerance. Using an established in vitro model of rapid ischemic tolerance, we show that WAVE-1 protein levels are stabilized following brief tolerance inducing ischemia (preconditioning). The stabilization appears to be due to a reduction in the ubiquitination of WAVE-1. Levels of ARP2, ARP3 and N-WASP were not affected by ischemic preconditioning. Immunocytochemical studies show a relocalization of ARP2 and ARP3 proteins in neurons following preconditioning ischemia, as well as a re-organization of actin. Blocking the protein kinase CK2 using emodin blocks ischemic tolerance, and our data suggests CK2 binds to WAVE-1 in neurons. We observe an increase in binding of the ARP2 subunit with WAVE-1. The neuroprotection observed following preconditioning is inhibited when cells are transduced with an N-WASP CA domain that blocks the activation of ARP2/3. Together these data show that ischemia affects actin regulating enzymes, and that the ARP2/3 pathway plays a role in rapid ischemic tolerance induced neuroprotection.
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Affiliation(s)
- Veronica J Jessick
- Neuroscience Institute, Morehouse School of Medicine720 Westview Drive SW, Atlanta, GA, 30310, USA
| | - Mian Xie
- Neuroscience Institute, Morehouse School of Medicine720 Westview Drive SW, Atlanta, GA, 30310, USA
| | - Andrea N Pearson
- Neuroscience Institute, Morehouse School of Medicine720 Westview Drive SW, Atlanta, GA, 30310, USA
- Robert S. Dow Neurobiology Laboratories, Legacy ResearchPortland, Oregon, USA
| | - Dan J Torrey
- Neuroscience Institute, Morehouse School of Medicine720 Westview Drive SW, Atlanta, GA, 30310, USA
| | - Michelle D Ashley
- Neuroscience Institute, Morehouse School of Medicine720 Westview Drive SW, Atlanta, GA, 30310, USA
| | - Simon Thompson
- Neuroscience Institute, Morehouse School of Medicine720 Westview Drive SW, Atlanta, GA, 30310, USA
| | - Robert Meller
- Neuroscience Institute, Morehouse School of Medicine720 Westview Drive SW, Atlanta, GA, 30310, USA
- Robert S. Dow Neurobiology Laboratories, Legacy ResearchPortland, Oregon, USA
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Caldeira MV, Salazar IL, Curcio M, Canzoniero LMT, Duarte CB. Role of the ubiquitin-proteasome system in brain ischemia: friend or foe? Prog Neurobiol 2013; 112:50-69. [PMID: 24157661 DOI: 10.1016/j.pneurobio.2013.10.003] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 10/08/2013] [Accepted: 10/15/2013] [Indexed: 11/26/2022]
Abstract
The ubiquitin-proteasome system (UPS) is a catalytic machinery that targets numerous cellular proteins for degradation, thus being essential to control a wide range of basic cellular processes and cell survival. Degradation of intracellular proteins via the UPS is a tightly regulated process initiated by tagging a target protein with a specific ubiquitin chain. Neurons are particularly vulnerable to any change in protein composition, and therefore the UPS is a key regulator of neuronal physiology. Alterations in UPS activity may induce pathological responses, ultimately leading to neuronal cell death. Brain ischemia triggers a complex series of biochemical and molecular mechanisms, such as an inflammatory response, an exacerbated production of misfolded and oxidized proteins, due to oxidative stress, and the breakdown of cellular integrity mainly mediated by excitotoxic glutamatergic signaling. Brain ischemia also damages protein degradation pathways which, together with the overproduction of damaged proteins and consequent upregulation of ubiquitin-conjugated proteins, contribute to the accumulation of ubiquitin-containing proteinaceous deposits. Despite recent advances, the factors leading to deposition of such aggregates after cerebral ischemic injury remain poorly understood. This review discusses the current knowledge on the role of the UPS in brain function and the molecular mechanisms contributing to UPS dysfunction in brain ischemia with consequent accumulation of ubiquitin-containing proteins. Chemical inhibitors of the proteasome and small molecule inhibitors of deubiquitinating enzymes, which promote the degradation of proteins by the proteasome, were both shown to provide neuroprotection in brain ischemia, and this apparent contradiction is also discussed in this review.
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Affiliation(s)
- Margarida V Caldeira
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal; Department of Life Sciences, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Ivan L Salazar
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal; Doctoral Programme in Experimental Biology and Biomedicine, Center for Neuroscience and Cell Biology, University of Coimbra, Portugal; Institute for Interdisciplinary Research, University of Coimbra (IIIUC), Portugal
| | - Michele Curcio
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal; Department of Science and Technology, University of Sannio, Benevento, Italy
| | | | - Carlos B Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal; Department of Life Sciences, University of Coimbra, 3004-517 Coimbra, Portugal.
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Meller R, Galvan L, Lan JQ, Han E, Bauer J, Morris KT. Programmed cell death in a patient with hepatocellular carcinoma treated with yttrium-90 and doxorubicin-loaded beads. J Vasc Interv Radiol 2013; 24:1537-42.e2. [PMID: 24070510 DOI: 10.1016/j.jvir.2013.06.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Revised: 05/28/2013] [Accepted: 06/10/2013] [Indexed: 10/26/2022] Open
Abstract
Molecular analysis of apoptosis and autophagy pathways was performed from a single hepatocellular carcinoma treated with yttrium-90 and doxorubicin-loaded beads before resection and compared with normal liver tissue from the margins. Both bead formulations activated apoptosis-associated mechanisms and increased autophagy pathway protein levels. Increased DNA fragmentation and autophagy markers were seen in tumor treated with drug-eluting beads compared with yttrium-90-treated tumor. These results suggest that both microembolic therapies activate cell death signaling, although differences in apoptosis and autophagy pathways were seen in this patient. Knowledge of mechanisms of action for each treatment may enhance future therapeutic strategies.
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Affiliation(s)
- Robert Meller
- Robert S. Dow Neurobiology Laboratories, Portland, Oregon; Cancer Research Laboratories, Portland, Oregon; Department of Neurobiology, Morehouse School of Medicine, Atlanta, Georgia
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Qiang YW, Heuck CJ, Shaughnessy JD, Barlogie B, Epstein J. Proteasome inhibitors and bone disease. Semin Hematol 2013; 49:243-8. [PMID: 22726547 DOI: 10.1053/j.seminhematol.2012.04.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Bone disease in patients with multiple myeloma (MM) is characterized by increase in the numbers and activity of bone-resorpting osteoclasts and decrease in the number and function of bone-formation osteoblasts. MM-triggered inhibition of bone formation may stem from suppression of Wnt/β-catenin signaling, a pivotal pathway in the differentiation of mesenchymal stem cells (MSC) into osteoblasts, and regulating production of receptor activator of nuclear factor-κB ligand (RANKL)/osteoprotegerin (OPG) axis by osteoblasts. Proteasome inhibitors (PIs), such as bortezomib (Bz), induce activation of Wnt/β-catenin pathway and MSC differentiation toward osteoblasts. PIs also suppress osteoclastogenesis, possibly through regulating multiple pathways including NF-κB, Bim, and the ratio of RANKL/OPG. The critical role of PI in increasing osteoblast function and suppression of osteoclast activity is highlighted by clinical evidence of increases in bone formation and decreases in bone resorption makers. This review will discuss the function of PIs in stimulating bone formation and suppression of bone resorption, and the mechanism underlying this process that leads to inhibition bone disease in MM patients.
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Affiliation(s)
- Ya-Wei Qiang
- Myeloma Institute for Research and Therapy, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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30
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Ha Thi HT, Lim HS, Kim J, Kim YM, Kim HY, Hong S. Transcriptional and post-translational regulation of Bim is essential for TGF-β and TNF-α-induced apoptosis of gastric cancer cell. Biochim Biophys Acta Gen Subj 2013; 1830:3584-92. [DOI: 10.1016/j.bbagen.2013.03.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 03/04/2013] [Accepted: 03/07/2013] [Indexed: 12/14/2022]
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Schwartz C, Hampton M, Andrews MT. Seasonal and regional differences in gene expression in the brain of a hibernating mammal. PLoS One 2013; 8:e58427. [PMID: 23526982 PMCID: PMC3603966 DOI: 10.1371/journal.pone.0058427] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 02/04/2013] [Indexed: 12/21/2022] Open
Abstract
Mammalian hibernation presents a unique opportunity to study naturally occurring neuroprotection. Hibernating ground squirrels undergo rapid and extreme physiological changes in body temperature, oxygen consumption, and heart rate without suffering neurological damage from ischemia and reperfusion injury. Different brain regions show markedly different activity during the torpor/arousal cycle: the cerebral cortex shows activity only during the periodic returns to normothermia, while the hypothalamus is active over the entire temperature range. Therefore, region-specific neuroprotective strategies must exist to permit this compartmentalized spectrum of activity. In this study, we use the Illumina HiSeq platform to compare the transcriptomes of these two brain regions at four collection points across the hibernation season: April Active, October Active, Torpor, and IBA. In the cerebral cortex, 1,085 genes were found to be differentially expressed across collection points, while 1,063 genes were differentially expressed in the hypothalamus. Comparison of these transcripts indicates that the cerebral cortex and hypothalamus implement very different strategies during hibernation, showing less than 20% of these differentially expressed genes in common. The cerebral cortex transcriptome shows evidence of remodeling and plasticity during hibernation, including transcripts for the presynaptic cytomatrix proteins bassoon and piccolo, and extracellular matrix components, including laminins and collagens. Conversely, the hypothalamic transcriptome displays upregulation of transcripts involved in damage response signaling and protein turnover during hibernation, including the DNA damage repair gene RAD50 and ubiquitin E3 ligases UBR1 and UBR5. Additionally, the hypothalamus transcriptome also provides evidence of potential mechanisms underlying the hibernation phenotype, including feeding and satiety signaling, seasonal timing mechanisms, and fuel utilization. This study provides insight into potential neuroprotective strategies and hibernation control mechanisms, and also specifically shows that the hibernator brain exhibits both seasonal and regional differences in mRNA expression.
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Affiliation(s)
- Christine Schwartz
- Department of Biology, University of Minnesota Duluth, Duluth, Minnesota, United States of America
| | - Marshall Hampton
- Department of Mathematics and Statistics, University of Minnesota Duluth, Duluth, Minnesota, United States of America
| | - Matthew T. Andrews
- Department of Biology, University of Minnesota Duluth, Duluth, Minnesota, United States of America
- * E-mail:
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Hypoxic Postconditioning Inhibits Endoplasmic Reticulum Stress–Mediated Cardiomyocyte Apoptosis by Targeting PUMA. Shock 2013; 39:299-303. [DOI: 10.1097/shk.0b013e3182814483] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Abstract
In this review we identify and discuss some of the genomics studies of preconditioning and the ischemic tolerance phenomenon. Such studies have been attempted in multiple species, using different array technologies and with different preconditioning and tolerance models. In addition, studies are starting to reveal epigenetic mechanisms and modifiers of tolerance and preconditioning. Together these studies are starting to reveal some of the immense complexity of the ischemic tolerance phenomenon, yet further studies await to be performed.
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Affiliation(s)
- Robert Meller
- Neuroscience Institute, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA, 30310-1495 ; Department of Neurobiology, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA, 30310-1495 ; Department of Pharmacology, Morehouse School of Medicine, 720 Westview Drive SW, Atlanta, GA, 30310-1495
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Abstract
The ubiquitin proteasome system (UPS) has been the subject of intensive research over the past 20 years to define its role in normal physiology and in pathophysiology. Many of these studies have focused in on the cardiovascular system and have determined that the UPS becomes dysfunctional in several pathologies such as familial and idiopathic cardiomyopathies, atherosclerosis, and myocardial ischemia. This review presents a synopsis of the literature as it relates to the role of the UPS in myocardial ischemia. Studies have shown that the UPS is dysfunctional during myocardial ischemia, and recent studies have shed some light on possible mechanisms. Other studies have defined a role for the UPS in ischemic preconditioning which is best associated with myocardial ischemia and is thus presented here. Very recent studies have started to define roles for specific proteasome subunits and components of the ubiquitination machinery in various aspects of myocardial ischemia. Lastly, despite the evidence linking myocardial ischemia and proteasome dysfunction, there are continuing suggestions that proteasome inhibitors may be useful to mitigate ischemic injury. This review presents the rationale behind this and discusses both supportive and nonsupportive studies and presents possible future directions that may help in clarifying this controversy.
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Affiliation(s)
- Justine Calise
- Center for Heart and Lung Research, The Feinstein Institute for Medical Research, Manhasset, New York 11030, USA
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Differential regulation of Nedd4 ubiquitin ligases and their adaptor protein Ndfip1 in a rat model of ischemic stroke. Exp Neurol 2012; 235:326-35. [PMID: 22417925 DOI: 10.1016/j.expneurol.2012.02.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 02/20/2012] [Accepted: 02/25/2012] [Indexed: 01/31/2023]
Abstract
Ubiquitin-modification of proteins by E3 ubiquitin ligases is an important post-translational mechanism implicated in neuronal survival and injury following cerebral ischemia. However, of the 500 or so E3s thought to be present in mammalian cells, very few specific E3s have been identified and associated with brain ischemia. Here, we demonstrate endogenous induction of HECT-type E3 ligases of the Nedd4 family and their adaptor Nedd4-family interacting protein 1 (Ndfip1) following transient focal cerebral ischemia in rats. Ndfip1 is upregulated in surviving cortical neurons and its neuroprotective activity is correlated with Nedd4-2 upregulation, but not two other Nedd4 family members examined (Nedd4-1 and Itch). Immunoprecipitation assays confirmed biochemical binding of Ndfip1 with Nedd4-2 in the brain, with or without ischemic stroke, indicating their endogenous interaction. While Ndfip1 and Itch have been previously shown to interact outside of the nervous system, ischemic induction of Itch in the present study was associated with cellular survival independent of Ndfip1. Together, these findings demonstrate specific and differential regulation of Nedd4 family E3 ligases under ischemic conditions, and identify two E3 ligases and their adaptor that potentially regulate ubiquitination in ischemic stroke to provide neuroprotection.
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The transcription factor C/EBP delta has anti-apoptotic and anti-inflammatory roles in pancreatic beta cells. PLoS One 2012; 7:e31062. [PMID: 22347430 PMCID: PMC3275575 DOI: 10.1371/journal.pone.0031062] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Accepted: 01/01/2012] [Indexed: 12/31/2022] Open
Abstract
In the course of Type 1 diabetes pro-inflammatory cytokines (e.g., IL-1β, IFN-γ and TNF-α) produced by islet-infiltrating immune cells modify expression of key gene networks in β-cells, leading to local inflammation and β-cell apoptosis. Most known cytokine-induced transcription factors have pro-apoptotic effects, and little is known regarding “protective” transcription factors. To this end, we presently evaluated the role of the transcription factor CCAAT/enhancer binding protein delta (C/EBPδ) on β-cell apoptosis and production of inflammatory mediators in the rat insulinoma INS-1E cells, in purified primary rat β-cells and in human islets. C/EBPδ is expressed and up-regulated in response to the cytokines IL-1β and IFN-γ in rat β-cells and human islets. Small interfering RNA-mediated C/EBPδ silencing exacerbated IL-1β+IFN-γ-induced caspase 9 and 3 cleavage and apoptosis in these cells. C/EBPδ deficiency increased the up-regulation of the transcription factor CHOP in response to cytokines, enhancing expression of the pro-apoptotic Bcl-2 family member BIM. Interfering with C/EBPδ and CHOP or C/EBPδ and BIM in double knockdown approaches abrogated the exacerbating effects of C/EBPδ deficiency on cytokine-induced β-cell apoptosis, while C/EBPδ overexpression inhibited BIM expression and partially protected β-cells against IL-1β+IFN-γ-induced apoptosis. Furthermore, C/EBPδ silencing boosted cytokine-induced production of the chemokines CXCL1, 9, 10 and CCL20 in β-cells by hampering IRF-1 up-regulation and increasing STAT1 activation in response to cytokines. These observations identify a novel function of C/EBPδ as a modulatory transcription factor that inhibits the pro-apoptotic and pro-inflammatory gene networks activated by cytokines in pancreatic β-cells.
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Kitagawa K. Ischemic tolerance in the brain: endogenous adaptive machinery against ischemic stress. J Neurosci Res 2012; 90:1043-54. [PMID: 22302606 DOI: 10.1002/jnr.23005] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2011] [Revised: 10/25/2011] [Accepted: 11/18/2011] [Indexed: 01/10/2023]
Abstract
Although more than 100 drugs have been examined clinically, tissue plasminogen activator remains the only drug approved for the treatment of acute ischemic stroke. Since the discovery of ischemic tolerance, it has been widely recognized that the brain possesses an endogenous protective machinery to protect against ischemic stress. Recent studies have clarified that both the upregulation of neuroprotective signaling and the downregulation of inflammatory or apoptotic pathways are involved equally in the acquisition of ischemic tolerance. The triggering stimuli for ischemic stresses are divided into hypoxic, oxidant/inflammatory, and glutamate stress. Glutamate stress, particularly the synaptic stimulation of the N-methyl-D-aspartate receptor, leads to activation of the cAMP response element-binding protein, which could subsequently induce gene expression of several neuroprotective molecules. Gene reprogramming and metabolic downregulation are intimately involved in ischemic tolerance as well as in hibernation and hypothermia. Micro-RNAs may be a key player for tuning the level of gene expression in ischemic tolerance. Future research should be performed to investigate the most effective combination for brain protection, enhancement of cell survival signaling, and inhibition of the inflammatory or apoptotic pathways.
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Affiliation(s)
- Kazuo Kitagawa
- Department of Neurology, Stroke Center, Osaka University Graduate School of Medicine, Suita, Japan.
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NCX1 and NCX3: Two new effectors of delayed preconditioning in brain ischemia. Neurobiol Dis 2012; 45:616-23. [DOI: 10.1016/j.nbd.2011.10.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2011] [Revised: 09/22/2011] [Accepted: 10/08/2011] [Indexed: 01/06/2023] Open
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Powell SR, Herrmann J, Lerman A, Patterson C, Wang X. The ubiquitin-proteasome system and cardiovascular disease. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 109:295-346. [PMID: 22727426 DOI: 10.1016/b978-0-12-397863-9.00009-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Over the past decade, the role of the ubiquitin-proteasome system (UPS) has been the subject of numerous studies to elucidate its role in cardiovascular physiology and pathophysiology. There have been many advances in this field including the use of proteomics to achieve a better understanding of how the cardiac proteasome is regulated. Moreover, improved methods for the assessment of UPS function and the development of genetic models to study the role of the UPS have led to the realization that often the function of this system deviates from the norm in many cardiovascular pathologies. Hence, dysfunction has been described in atherosclerosis, familial cardiac proteinopathies, idiopathic dilated cardiomyopathies, and myocardial ischemia. This has led to numerous studies of the ubiquitin protein (E3) ligases and their roles in cardiac physiology and pathophysiology. This has also led to the controversial proposition of treating atherosclerosis, cardiac hypertrophy, and myocardial ischemia with proteasome inhibitors. Furthering our knowledge of this system may help in the development of new UPS-based therapeutic modalities for mitigation of cardiovascular disease.
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Affiliation(s)
- Saul R Powell
- Center for Heart and Lung Research, The Feinstein Institute for Medical Research, Manhasset, New York, USA
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Wang X, Li J, Zheng H, Su H, Powell SR. Proteasome functional insufficiency in cardiac pathogenesis. Am J Physiol Heart Circ Physiol 2011; 301:H2207-19. [PMID: 21949118 DOI: 10.1152/ajpheart.00714.2011] [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] [Indexed: 01/05/2023]
Abstract
The ubiquitin-proteasome system (UPS) is responsible for the degradation of most cellular proteins. Alterations in cardiac UPS, including changes in the degradation of regulatory proteins and proteasome functional insufficiency, are observed in many forms of heart disease and have been shown to play an important role in cardiac pathogenesis. In the past several years, remarkable progress in understanding the mechanisms that regulate UPS-mediated protein degradation has been achieved. A transgenic mouse model of benign enhancement of cardiac proteasome proteolytic function has been created. This has led to the first demonstration of the necessity of proteasome functional insufficiency in the genesis of important pathological processes. Cardiomyocyte-restricted enhancement of proteasome proteolytic function by overexpression of proteasome activator 28α protects against cardiac proteinopathy and myocardial ischemia-reperfusion injury. Additionally, exciting advances have recently been achieved in the search for a pharmacological agent to activate the proteasome. These breakthroughs are expected to serve as an impetus to further investigation into the involvement of UPS dysfunction in molecular pathogenesis and to the development of new therapeutic strategies for combating heart disease. An interplay between the UPS and macroautophagy is increasingly suggested in noncardiac systems but is not well understood in the cardiac system. Further investigations into the interplay are expected to provide a more comprehensive picture of cardiac protein quality control and degradation.
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Affiliation(s)
- Xuejun Wang
- Division of Basic Biomedical Sciences, Protein Quality Control and Degradation Research Center, Sanford School of Medicine, University of South Dakota, Vermillion, South Dakota 57069, USA.
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41
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Rehni AK, Singh TG, Behl N, Arora S. Possible involvement of ubiquitin proteasome system and other proteases in acute and delayed aspects of ischemic preconditioning of brain in mice. Biol Pharm Bull 2011; 33:1953-7. [PMID: 21139232 DOI: 10.1248/bpb.33.1953] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study has been designed to investigate the potential role of ubiquitin proteasome system and other proteases in acute as well as delayed aspects of ischemic preconditioning induced reversal of ischemia-reperfusion injury in mouse brain. Bilateral carotid artery occlusion of 17 min followed by reperfusion for 24 h was employed in present study to produce ischemia and reperfusion induced cerebral injury in mice. Cerebral infarct size was measured using triphenyltetrazolium chloride staining. Memory was evaluated using elevated plus-maze test. Rota rod test was employed to assess motor incoordination. Bilateral carotid artery occlusion followed by reperfusion produced cerebral infarction and impaired memory and motor co-ordination. Three preceding episodes of bilateral carotid artery occlusion for 1 min and reperfusion of 1 min (ischemic preconditioning) both immediately before (for acute preconditioning) and 24 h before (for delayed preconditioning) global cerebral ischemia prevented markedly ischemia-reperfusion-induced cerebral injury as measured in terms of infarct size, loss of memory and motor coordination. Z-Leu-Leu-Phe-Chinese hamster ovary (CHO) (2 mg/kg, intraperitoneally (i.p.)), an inhibitor of ubiquitin proteasome system and other proteases attenuated the neuroprotective effect of both the acute as well as delayed ischemic preconditioning. It is concluded that the neuroprotective effect of both the acute as well as delayed phases of ischemic preconditioning may be due to the activation of ubiquitin proteasome system and other proteases.
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Shi J, Zhou Y, Huang HC, Mitchison TJ. Navitoclax (ABT-263) accelerates apoptosis during drug-induced mitotic arrest by antagonizing Bcl-xL. Cancer Res 2011; 71:4518-26. [PMID: 21546570 DOI: 10.1158/0008-5472.can-10-4336] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Combining microtubule-targeting antimitotic drugs with targeted apoptosis potentiators is a promising new chemotherapeutic strategy to treat cancer. In this study, we investigate the cellular mechanism by which navitoclax (previously called ABT-263), a Bcl-2 family inhibitor, potentiates apoptosis triggered by paclitaxel and an inhibitor of kinesin-5 (K5I, also called a KSP inhibitor), across a panel of epithelial cancer lines. By using time-lapse microscopy, we showed that navitoclax has little effect on cell death during interphase, but strongly accelerates apoptosis during mitotic arrest, and greatly increases the fraction of apoptosis-resistant cells that die. By systematically knocking down individual Bcl-2 proteins, we determined that Mcl-1 and Bcl-xL are the primary negative regulators of apoptosis during prolonged mitotic arrest. Mcl-1 levels decrease during mitotic arrest because of an imbalance between synthesis and turnover, and turnover depends in part on the MULE/HUWE1 E3 ligase. The combination of Mcl-1 loss with inhibition of Bcl-xL by navitoclax causes rapid apoptosis in all lines tested. Variation in expression levels of Mcl-1 and Bcl-xL largely determines variation in response to antimitotics alone, and antimitotics combined with navitoclax, across our panel. We concluded that Bcl-xL is a critical target of Bcl-2 family inhibitors for enhancing the lethality of antimitotic drugs in epithelial cancers, and combination treatment with navitoclax and a spindle specific antimitotic, such as a K5I, might be more effective than paclitaxel alone.
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Affiliation(s)
- Jue Shi
- Center for Quantitative Systems Biology and Department of Physics, Hong Kong Baptist University, Hong Kong, China.
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In vivo contributions of BH3-only proteins to neuronal death following seizures, ischemia, and traumatic brain injury. J Cereb Blood Flow Metab 2011; 31:1196-210. [PMID: 21364604 PMCID: PMC3099642 DOI: 10.1038/jcbfm.2011.26] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The Bcl-2 homology (BH) domain 3-only proteins are a proapoptotic subgroup of the Bcl-2 gene family, which regulate cell death via effects on mitochondria. The BH3-only proteins react to various cell stressors and promote cell death by binding and inactivating antiapoptotic Bcl-2 family members and direct activation of proapoptotic multi-BH domain proteins such as Bax. Here, we review the in vivo evidence for their involvement in the pathophysiology of status epilepticus and contrast it to ischemia and traumatic brain injury. Seizures in rodents activate three potent proapoptotic BH3-only proteins: Bid, Bim, and Puma. Analysis of damage after seizures in mice singly deficient for each BH3-only protein supports a causal role for Puma and to a lesser extent Bim but, surprisingly, not Bid. In ischemia and trauma, where core aspects of the pathophysiology of cell death overlap, multiple BH3-only proteins are also activated and Bid has been shown to be required for neuronal death. The findings suggest that while each neurologic insult activates multiple BH3-only proteins, there may be specificity in their functional contribution. Future challenges include evaluating the remaining BH3-only proteins, explaining different causal contributions, and, if possible, exploring neurologic outcomes in mouse models deficient for multiple BH3-only proteins.
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44
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Thompson S, Pearson AN, Ashley MD, Jessick V, Murphy BM, Gafken P, Henshall DC, Morris KT, Simon RP, Meller R. Identification of a novel Bcl-2-interacting mediator of cell death (Bim) E3 ligase, tripartite motif-containing protein 2 (TRIM2), and its role in rapid ischemic tolerance-induced neuroprotection. J Biol Chem 2011; 286:19331-9. [PMID: 21478148 DOI: 10.1074/jbc.m110.197707] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have previously shown that the cell death-promoting protein Bcl-2-interacting mediator of cell death (Bim) is ubiquitinated and degraded following a neuroprotection-conferring episode of brief ischemia (preconditioning). Here, we identify the E3 ligase that ubiquitinates Bim in this model, using a proteomics approach. Using phosphorylated GST-Bim as bait, we precipitated and identified by mass spectrometry tripartite motif protein 2 (TRIM2), a RING (really interesting new gene) domain-containing protein. The reaction between TRIM2 and Bim was confirmed using co-immunoprecipitation followed by immunoblotting. We show that TRIM2 binds to Bim when it is phosphorylated by p42/p44 MAPK but does not interact with a nonphosphorylatable Bim mutant (3ABim). 12-O-tetradecanoylphorbol-13-acetate activation of p42/p44 MAPK drives Bim ubiquitination in mouse embryonic fibroblast cells and is associated with an increased interaction between TRIM2 and Bim. One hour following preconditioning ischemia, the binding of Bim to TRIM2 increased, consistent with the time window of enhanced Bim degradation. Blocking p42/p44 MAPK activation following preconditioning ischemia with U0126 or using the nonphosphorylatable 3ABim reduced the binding between Bim and TRIM2. Immunodepletion of TRIM2 from cell lysates prepared from preconditioned cells reduced Bim ubiquitination. Finally, suppression of TRIM2 expression, using lentivirus transduction of shRNAmir, stabilized Bim protein levels and blocked neuroprotection observed in rapid ischemic tolerance. Taken together, these data support a role for TRIM2 in mediating the p42/p44 MAPK-dependent ubiquitination of Bim in rapid ischemic tolerance.
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Affiliation(s)
- Simon Thompson
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia 30310-1495, USA
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45
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Ishihara Y, Takeuchi K, Ito F, Shimamoto N. Dual regulation of hepatocyte apoptosis by reactive oxygen species: Increases in transcriptional expression and decreases in proteasomal degradation of BimEL. J Cell Physiol 2011; 226:1007-16. [DOI: 10.1002/jcp.22414] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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46
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Tsuchiya T, Bonner HP, Engel T, Woods I, Matsushima S, Ward MW, Taki W, Henshall DC, Concannon CG, Prehn JHM. Bcl-2 homology domain 3-only proteins Puma and Bim mediate the vulnerability of CA1 hippocampal neurons to proteasome inhibition in vivo. Eur J Neurosci 2010; 33:401-8. [PMID: 21198986 DOI: 10.1111/j.1460-9568.2010.07538.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Bcl-2 homology domain 3 (BH3)-only proteins are pro-apoptotic Bcl-2 family members that play important roles in upstream cell death signalling during apoptosis. Proteasomal stress has been shown to contribute to the pathology of cerebral ischaemia and many neurodegenerative disorders. Here we explored the contribution of BH3-only proteins in mediating proteasome-inhibition-induced apoptosis in the murine brain in vivo. Stereotactic intrahippocampal microinjection of the selective proteasome inhibitor epoxomicin (2.5 nmol) induced a delayed apoptosis within only the CA1 hippocampal neurons and not neurons within the CA3 or dentate gyrus regions, a selective vulnerability similar to that seen during ischaemia. This injury developed over a time-course of 3 days and was characterized by positive terminal deoxynucleotidyl transferase dUTP nick end labelling staining and nuclear condensation. Previous work from our laboratory has identified the BH3-only protein p53-upregulated mediator of apoptosis (Puma) as mediating proteasome-inhibition-induced apoptosis in cultured neural cells. Genetic deletion of puma reduced the number of terminal deoxynucleotidyl transferase dUTP nick end labelling-positive cells within the CA1 following epoxomicin microinjection but it did not provide a complete protection. Subsequent studies identified the BH3-only protein Bim as also being upregulated during proteasome inhibition in organotypic hippocampal slice cultures and after epoxomicin treatment in vivo. Interestingly, the genetic deletion of bim also afforded significant neuroprotection, although this protection was less pronounced. In summary, we demonstrate that the BH3-only proteins Puma and Bim mediate the delayed apoptosis of CA1 hippocampal neurons induced by proteasome inhibition in vivo, and that either BH3-only protein can only partly compensate for the deficiency of the other.
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Affiliation(s)
- Takuro Tsuchiya
- Department of Physiology and Medical Physics and RCSI Neuroscience Research Centre, Royal College of Surgeons in Ireland, 123 St Stephen's Green, Dublin 2, Ireland
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47
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Geng CD, Vedeckis WV. Use of recombinant cell-permeable small peptides to modulate glucocorticoid sensitivity of acute lymphoblastic leukemia cells. Biochemistry 2010; 49:8892-901. [PMID: 20831260 DOI: 10.1021/bi1007723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glucocorticoid (GC) hormones induce apoptosis in T-cell and pre-B-cell acute lymphoblastic leukemia (ALL) cells. Steroid-mediated apoptosis requires a threshold level of the glucocorticoid receptor (GR) protein, and increasing the intracellular GR levels in ALL cells would augment their hormone sensitivity. A protein transduction domain (PTD) approach was used to accomplish this. We produced an HIV Tat PTD domain fusion protein (Tat-GR(554-777)) that potentially competes for the degradation of GR protein by the ubiquitin-proteasome system and should thus increase its intracellular levels by "stabilizing" the GR. We also designed a fusion peptide for the c-Myb DNA binding domain, Tat-c-Myb DBD, since the biological function of this peptide as a dominant negative inhibitor of the c-Myb protein was already known. Purified, bacterially expressed Tat-c-Myb DBD and Tat-GR(554-777) exhibited highly efficient transduction into cultured ALL cell lines including 697 (pre-B-ALL) and CEM-C7 (T-ALL) cells. As expected, the transduced Tat-c-Myb DBD peptide inhibited steroid-mediated stimulation of a GR promoter-luciferase reporter gene. Significantly, transduced Tat-GR(554-777) effectively increased intracellular GR levels in the GC-resistant T-ALL cell line, CEM-C1, and in the pre-B-ALL 697 cell line. Furthermore, transduction of Tat-GR(554-777) rendered GC-resistant CEM-C1 cells sensitive to steroid killing and further sensitized 697 cells to steroid. The use of Tat-fusion peptide transduction may eventually lead to innovative therapeutic modalities to improve the clinical response of patients suffering from T-cell and pre-B-cell acute lymphoblastic leukemia by increasing steroid responsiveness and perhaps converting steroid-resistant leukemia to a hormone-responsive phenotype.
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Affiliation(s)
- Chuan-dong Geng
- Department of Biochemistry and Molecular Biology and Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA.
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Puerta E, Pastor F, Dvoracek J, De Saavedra MDM, Goñi-Allo B, Jordán J, Hervias I, Aguirre N. Delayed pre-conditioning by 3-nitropropionic acid prevents 3,4-methylenedioxymetamphetamine-induced 5-HT deficits. J Neurochem 2010; 114:843-52. [DOI: 10.1111/j.1471-4159.2010.06808.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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49
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Tanaka K, Jimenez-Mateos EM, Matsushima S, Taki W, Henshall DC. Hippocampal damage after intra-amygdala kainic acid-induced status epilepticus and seizure preconditioning-mediated neuroprotection in SJL mice. Epilepsy Res 2010; 88:151-61. [PMID: 19931419 DOI: 10.1016/j.eplepsyres.2009.10.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 10/20/2009] [Accepted: 10/21/2009] [Indexed: 12/30/2022]
Abstract
Exposure of the brain to a stressful stimulus that is sub-threshold for permanent injury can temporarily protect against cell death during a subsequent and otherwise damaging insult. One or more brief, non-harmful seizure episode(s) (seizure preconditioning) can dramatically reduce hippocampal damage when given prior to status epilepticus (epileptic tolerance). We recently reported that status epilepticus-induced hippocampal damage in C57BL/6 mice could be reduced by approximately 50% when preceded 24h earlier by a brief, non-injurious generalized seizure induced by 15mg/kg systemic kainic acid (KA). Since other mouse strains might display different vulnerability to either seizure preconditioning or status epilepticus, we investigated whether epileptic tolerance could be acquired in another strain. SJL mice, reported to display greater seizure sensitivity to systemic KA, received intra-amygdala microinjection of KA to trigger status epilepticus. Intracerebral recordings confirmed evoked seizures involved the ipsilateral hippocampus. Status epilepticus produced hippocampal damage which mainly affected the ipsilateral CA3 and hilus; a pattern similar to C57BL/6 mice. The damage extended through the full rostro-caudal extent of the hippocampal formation. Seizure preconditioning using 20mg/kg systemic KA, but not 15mg/kg, significantly reduced hippocampal damage after status epilepticus by 37% in the dorsal hippocampus and by 65% in the ventral hippocampus. These studies suggest status epilepticus induced by intra-amygdala KA in SJL mice models aspects of the pathophysiology of human mesial temporal sclerosis. Moreover, seizure preconditioning effectively produces neuroprotection in SJL mice, further establishing epileptic tolerance as a conserved endogenous neuroprotection paradigm.
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Affiliation(s)
- Katsuhiro Tanaka
- Department of Physiology & Medical Physics, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland
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50
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Ordonez AN, Jessick VJ, Clayton CE, Ashley MD, Thompson SJ, Simon RP, Meller R. Rapid ischemic tolerance induced by adenosine preconditioning results in Bcl-2 interacting mediator of cell death (Bim) degradation by the proteasome. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2010; 2:36-44. [PMID: 20957068 PMCID: PMC2955863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Accepted: 12/21/2009] [Indexed: 05/30/2023]
Abstract
Rapid ischemic tolerance, induced one hour following ischemic preconditioning, is mediated via the ubiq-uitin-proteasome system and the degradation of the pro-apoptotic bcl-2 family protein Bim. Previous studies implicate adenosine A1 receptors in mediating rapid ischemic tolerance. Since the A1 adenosine receptor antagonist DPCPX (10µM) blocked rapid ischemic tolerance in our model, we investigated whether adenosine-mediated preconditioning induces rapid ischemic tolerance via the proteasomal degradation of Bim. Cultured rat cortical neurons were incubated for 60 minutes with either adenosine (1µM) or (-)-N(6)-(2-Phenyl-isopropyl) adenosine (RPIA (1µM)), prior to a harmful dose of ischemia (120min oxygen and glucose deprivation). Preconditioned cells had significantly lower levels of cell death following harmful ischemia when compared to non-preconditioned cells. The proteasome inhibitor MG132 (0.1µM) blocked the protective effect of adenosine pre-conditioning. Immunoblot analysis revealed a decrease in Bim protein levels in adenosine and RPIA preconditioned neurons. Adenosine preconditioning induced neuroprotection and Bim degradation was blocked by the MEK inhibitor UO126 (10µM). Our data suggests that pharmacological preconditioning with adenosine results in proteasomal Bim degradation mediated by p42/44 MAPK. Therefore, pharmacological approaches may be able to induce rapid ischemic tolerance via similar molecular mechanisms as ischemic preconditioning.
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Affiliation(s)
- Andrea Nicole Ordonez
- Robert S. Dow Neurobiology Laboratories, Legacy Research Portland, Oregon 97232, USA
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