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Sumida K, Doi T, Obayashi K, Chiba Y, Nagasaka S, Ogino N, Miyagawa K, Baba R, Morimoto H, Hara H, Terabayashi T, Ishizaki T, Harada M, Endo M. Caspase-4 has a role in cell division in epithelial cells through actin depolymerization. Biochem Biophys Res Commun 2024; 695:149394. [PMID: 38157629 DOI: 10.1016/j.bbrc.2023.149394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 12/14/2023] [Indexed: 01/03/2024]
Abstract
In addition to its role in pyroptosis and inflammatory cytokine maturation, caspase-4 (CASP4) also contributes to the fusion of phagosomes with lysosomes and cell migration. However, its role in cell division remains elusive. In this study, we demonstrate that CASP4 is indispensable for proper cell division in epithelial cells. Knockout of CASP4 (CASP4 KO) in HepG2 cells led to delayed cell proliferation, increased cell size, and increased multinucleation. In mitosis, CASP4 KO cells showed multipolar spindles, asymmetric spindle positioning, and chromosome segregation errors, ultimately increasing DNA content and chromosome number. We also found that phalloidin, a marker of filamentous actin, increased in CASP4 KO cells owing to suppressed actin depolymerization. Moreover, the levels of actin polymerization-related proteins, including Rho-associated protein kinase1 (ROCK1), LIM kinase1 (LIMK1), and phosphorylated cofilin, significantly increased in CASP4 KO cells. These results suggest that CASP4 contributes to proper cell division through actin depolymerization.
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Affiliation(s)
- Kazuhiro Sumida
- Third Department of Internal Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan; Department of Molecular Biology, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Tomomitsu Doi
- Department of Molecular Biology, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Kunie Obayashi
- Department of Molecular Biology, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Yosuke Chiba
- Department of Molecular Biology, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Shohei Nagasaka
- Department of Molecular Biology, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Noriyoshi Ogino
- Third Department of Internal Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Koichiro Miyagawa
- Third Department of Internal Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Ryoko Baba
- Department of Anatomy, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Hiroyuki Morimoto
- Department of Anatomy, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Hideki Hara
- Department of Infectious Diseases, Division of Microbiology and Immunochemistry, Asahikawa Medical University, Asahikawa, Japan
| | - Takeshi Terabayashi
- Department of Pharmacology, Faculty of Medicine, Oita University, Yufu, Japan
| | - Toshimasa Ishizaki
- Department of Pharmacology, Faculty of Medicine, Oita University, Yufu, Japan
| | - Masaru Harada
- Third Department of Internal Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Motoyoshi Endo
- Department of Molecular Biology, University of Occupational and Environmental Health, Kitakyushu, Japan.
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Shteinfer-Kuzmine A, Verma A, Arif T, Aizenberg O, Paul A, Shoshan-Barmaz V. Mitochondria and nucleus cross-talk: Signaling in metabolism, apoptosis, and differentiation, and function in cancer. IUBMB Life 2021; 73:492-510. [PMID: 33179373 DOI: 10.1002/iub.2407] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/15/2020] [Accepted: 10/21/2020] [Indexed: 12/12/2022]
Abstract
The cross-talk between the mitochondrion and the nucleus regulates cellular functions, including differentiation and adaptation to stress. Mitochondria supply metabolites for epigenetic modifications and other nuclear-associated activities and certain mitochondrial proteins were found in the nucleus. The voltage-dependent anion channel 1 (VDAC1), localized at the outer mitochondrial membrane (OMM) is a central protein in controlling energy production, cell growth, Ca2+ homeostasis, and apoptosis. To alter the cross-talk between the mitochondria and the nucleus, we used specific siRNA to silence the expression of VDAC1 in glioblastoma (GBM) U87-MG and U118-MG cell-derived tumors, and then monitored the nuclear localization of mitochondrial proteins and the methylation and acetylation of histones. Depletion of VDAC1 from tumor cells reduced metabolism, leading to inhibition of tumor growth, and several tumor-associated processes and signaling pathways linked to cancer development. In addition, we demonstrate that certain mitochondrial pro-apoptotic proteins such as caspases 3, 8, and 9, and p53 were unexpectedly overexpressed in tumors, suggesting that they possess additional non-apoptotic functions. VDAC1 depletion and metabolic reprograming altered their expression levels and subcellular localization, specifically their translocation to the nucleus. In addition, VDAC1 depletion also leads to epigenetic modifications of histone acetylation and methylation, suggesting that the interchange between metabolism and cancer signaling pathways involves mitochondria-nucleus cross-talk. The mechanisms regulating mitochondrial protein trafficking into and out of the nucleus and the role these proteins play in the nucleus remain to be elucidated.
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Affiliation(s)
- Anna Shteinfer-Kuzmine
- Department of Life Sciences, Ben-Gurion University of the Negev and the National Institute for Biotechnology in the Negev, Beersheba, Israel
| | - Ankit Verma
- Department of Life Sciences, Ben-Gurion University of the Negev and the National Institute for Biotechnology in the Negev, Beersheba, Israel
| | - Tasleem Arif
- Department of Life Sciences, Ben-Gurion University of the Negev and the National Institute for Biotechnology in the Negev, Beersheba, Israel
- Department of Cell, Developmental, & Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Or Aizenberg
- Department of Life Sciences, Ben-Gurion University of the Negev and the National Institute for Biotechnology in the Negev, Beersheba, Israel
| | - Avijit Paul
- Department of Life Sciences, Ben-Gurion University of the Negev and the National Institute for Biotechnology in the Negev, Beersheba, Israel
- Special Center for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Varda Shoshan-Barmaz
- Department of Life Sciences, Ben-Gurion University of the Negev and the National Institute for Biotechnology in the Negev, Beersheba, Israel
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3
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Olfactory bulb atrophy and caspase activation observed in the BACHD rat models of Huntington disease. Neurobiol Dis 2019; 125:219-231. [DOI: 10.1016/j.nbd.2019.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 12/14/2018] [Accepted: 02/04/2019] [Indexed: 01/08/2023] Open
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Rebellato P, Kaczynska D, Kanatani S, Rayyes IA, Zhang S, Villaescusa C, Falk A, Arenas E, Hermanson O, Louhivuori L, Uhlén P. The T-type Ca 2+ Channel Ca v3.2 Regulates Differentiation of Neural Progenitor Cells during Cortical Development via Caspase-3. Neuroscience 2019; 402:78-89. [PMID: 30677486 DOI: 10.1016/j.neuroscience.2019.01.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 12/11/2018] [Accepted: 01/12/2019] [Indexed: 01/02/2023]
Abstract
Here we report that the low-voltage-dependent T-type calcium (Ca2+) channel Cav3.2, encoded by the CACNA1H gene, regulates neuronal differentiation during early embryonic brain development through activating caspase-3. At the onset of neuronal differentiation, neural progenitor cells exhibited spontaneous Ca2+ activity. This activity strongly correlated with the upregulation of CACNA1H mRNA. Cells exhibiting robust spontaneous Ca2+ signaling had increased caspase-3 activity unrelated to apoptosis. Inhibition of Cav3.2 by drugs or viral CACNA1H knock down resulted in decreased caspase-3 activity followed by suppressed neurogenesis. In contrast, when CACNA1H was overexpressed, increased neurogenesis was detected. Cortical slices from Cacna1h knockout mice showed decreased spontaneous Ca2+ activity, a significantly lower protein level of cleaved caspase-3, and microanatomical abnormalities in the subventricular/ventricular and cortical plate zones when compared to their respective embryonic controls. In summary, we demonstrate a novel relationship between Cav3.2 and caspase-3 signaling that affects neurogenesis in the developing brain.
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Affiliation(s)
- Paola Rebellato
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Dagmara Kaczynska
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Shigeaki Kanatani
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Ibrahim Al Rayyes
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Songbai Zhang
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Carlos Villaescusa
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Anna Falk
- Department of Neuroscience, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Ernest Arenas
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Ola Hermanson
- Department of Neuroscience, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Lauri Louhivuori
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
| | - Per Uhlén
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
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Mitochondrial VDAC1 Silencing Leads to Metabolic Rewiring and the Reprogramming of Tumour Cells into Advanced Differentiated States. Cancers (Basel) 2018; 10:cancers10120499. [PMID: 30544833 PMCID: PMC6316808 DOI: 10.3390/cancers10120499] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 11/27/2018] [Accepted: 12/04/2018] [Indexed: 01/10/2023] Open
Abstract
Oncogenic properties, along with the metabolic reprogramming necessary for tumour growth and motility, are acquired by cancer cells. Thus, tumour metabolism is becoming a target for cancer therapy. Here, cancer cell metabolism was tackled by silencing the expression of voltage-dependent anion channel 1 (VDAC1), a mitochondrial protein that controls cell energy, as well as metabolic and survival pathways and that is often over-expressed in many cancers. We demonstrated that silencing VDAC1 expression using human-specific siRNA (si-hVDAC1) inhibited cancer cell growth, both in vitro and in mouse xenograft models of human glioblastoma (U-87MG), lung cancer (A549), and triple negative breast cancer (MDA-MB-231). Importantly, treatment with si-hVDAC1 induced metabolic rewiring of the cancer cells, reversing their oncogenic properties and diverting them towards differentiated-like cells. The si-hVDAC1-treated residual “tumour” showed reprogrammed metabolism, decreased proliferation, inhibited stemness and altered expression of genes and proteins, leading to cell differentiation toward less malignant lineages. These VDAC1 depletion-mediated effects involved alterations in master transcription factors associated with cancer hallmarks, such as highly increased expression of p53 and decreased expression of HIF-1a and c-Myc that regulate signalling pathways (e.g., AMPK, mTOR). High expression of p53 and the pro-apoptotic proteins cytochrome c and caspases without induction of apoptosis points to functions for these proteins in promoting cell differentiation. These results clearly show that VDAC1 depletion similarly leads to a rewiring of cancer cell metabolism in breast and lung cancer and glioblastoma, regardless of origin or mutational status. This metabolic reprogramming results in cell growth arrest and inhibited tumour growth while encouraging cell differentiation, thus generating cells with decreased proliferation capacity. These results further suggest VDAC1 to be an innovative and markedly potent therapeutic target.
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Stevenson ME, Lensmire NA, Swain RA. Astrocytes and radial glia-like cells, but not neurons, display a nonapoptotic increase in caspase-3 expression following exercise. Brain Behav 2018; 8:e01110. [PMID: 30240148 PMCID: PMC6192401 DOI: 10.1002/brb3.1110] [Citation(s) in RCA: 10] [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: 03/01/2018] [Revised: 06/18/2018] [Accepted: 08/05/2018] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Exercise induces plasticity in the hippocampus, which includes increases in neurogenesis, the proliferation of new neurons, and angiogenesis, the sprouting of new capillaries from preexisting blood vessels. Following exercise, astrocytes also undergo morphological changes that parallel the events occurring in the neurovascular system. Interestingly, there have also been reports of apoptosis in the hippocampus following aerobic exercise. This experiment aimed to identify which population of hippocampal cells undergoes apoptosis after an acute bout of exercise. METHODS Cleaved caspase-3, a terminal protein in the apoptotic cascade, was initially used to identify apoptotic cells in the hippocampus after rats completed an acute bout of exercise. Next, the proportion of immature neurons, adult neurons, astrocytes, or radial glia-like cells expressing cleaved caspase-3 was quantified. TUNEL staining was completed as a second measure of apoptosis. RESULTS Following exercise, cleaved caspase-3 expression was increased in the CA1 and DG regions of the hippocampus. Cleaved caspase-3 was not highly expressed in neuronal populations, and expression was not increased in these cells postexercise. Instead, cleaved caspase-3 was predominantly expressed in astrocytes. Following exercise, there was an increased number of cleaved caspase-3 positive astrocytes in DG and CA1, and cleaved caspase-3 positive radial glia-like cells located in the subgranular zone. To determine whether cleaved caspase-3 expression in these glial cells was associated with apoptosis, a TUNEL assay was completed. TUNEL staining was negligible in all groups and did not mirror the pattern of caspase-3 labeling. CONCLUSIONS Cleaved caspase-3 expression was detected largely in non-neuronal cell populations, and the pattern of cleaved caspase-3 expression did not match that of TUNEL. This suggests that after exercise, cleaved caspase-3 expression may serve a nonapoptotic role in these hippocampal astrocytes and radial glia-like cells. It will be important to identify the function of exercise-induced cleaved caspase-3 expression in the future experiments.
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Affiliation(s)
| | - Nicole A. Lensmire
- Department of PsychologyUniversity of Wisconsin‐MilwaukeeMilwaukeeWisconsin
| | - Rodney A. Swain
- Department of PsychologyUniversity of Wisconsin‐MilwaukeeMilwaukeeWisconsin
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McArthur K, Kile BT. Apoptotic Caspases: Multiple or Mistaken Identities? Trends Cell Biol 2018; 28:475-493. [PMID: 29551258 DOI: 10.1016/j.tcb.2018.02.003] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Revised: 01/31/2018] [Accepted: 02/07/2018] [Indexed: 12/22/2022]
Abstract
The mitochondrial caspase cascade was originally thought to be required for apoptotic death driven by Bak/Bax-mediated intrinsic apoptosis. It has also been ascribed several 'non-apoptotic' functions, including differentiation, proliferation, and cellular reprogramming. Recent work has demonstrated that, during apoptosis, the caspase cascade suppresses damage-associated molecular pattern (DAMP)-initiated production of cytokines such as type I interferon by the dying cell. The caspase cascade is not required for death to occur; instead, it shapes the immunogenic properties of the apoptotic cell. This raises questions about the role of apoptotic caspases in regulating DAMP signaling more generally, puts a new perspective on their non-apoptotic functions, and suggests that pharmacological caspase inhibitors might find new applications as antiviral or anticancer agents.
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Affiliation(s)
- Kate McArthur
- Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia
| | - Benjamin T Kile
- Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.
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8
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Neuronal Loss in the Developing Cerebral Cortex of Normal and Bax-Deficient Mice: Effects of Ethanol Exposure. Neuroscience 2018; 369:278-291. [DOI: 10.1016/j.neuroscience.2017.11.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 11/03/2017] [Accepted: 11/06/2017] [Indexed: 11/21/2022]
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9
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When dying is not the end: Apoptotic caspases as drivers of proliferation. Semin Cell Dev Biol 2017; 82:86-95. [PMID: 29199139 DOI: 10.1016/j.semcdb.2017.11.036] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 11/29/2017] [Accepted: 11/29/2017] [Indexed: 12/21/2022]
Abstract
Caspases are well known for their role as executioners of apoptosis. However, recent studies have revealed that these lethal enzymes also have important mitogenic functions. Caspases can promote proliferation through autonomous regulation of the cell cycle, as well as by induction of secreted signals, which have a profound impact in neighboring tissues. Here, I review the proliferative role of caspases during development and homeostasis, in addition to their key regenerative function during tissue repair upon injury. Furthermore, the emerging properties of apoptotic caspases as drivers of carcinogenesis are discussed, as well as their involvement in other diseases. Finally, I examine further effects of caspases regulating death and survival in a non-autonomous manner.
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Arif T, Krelin Y, Shoshan-Barmatz V. Reducing VDAC1 expression induces a non-apoptotic role for pro-apoptotic proteins in cancer cell differentiation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1228-1242. [PMID: 27080741 DOI: 10.1016/j.bbabio.2016.04.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Revised: 04/07/2016] [Accepted: 04/07/2016] [Indexed: 12/30/2022]
Abstract
Proteins initially identified as essential for apoptosis also mediate a wide range of non-apoptotic functions that include cell cycle progression, differentiation and metabolism. As this phenomenon was mostly reported with non-cancer cells, we considered non-conventional roles for the apoptotic machinery in the cancer setting. We found that treating glioblastoma (GBM) tumors with siRNA against VDAC1, a mitochondrial protein found at the crossroads of metabolic and survival pathways and involved in apoptosis, inhibited tumor growth while leading to differentiation of tumor cells into neuronal-like cells, as reflected in the expression of specific markers. Although VDAC1 depletion did not induce apoptosis, the expression levels of several pro-apoptotic regulatory proteins were changed. Specifically, VDAC1 deletion led to up-regulation of caspases, p53, cytochrome c, and down-regulation of SMAC/Diablo, AIF and TSPO. The down-regulated group was highly expressed in U-87MG xenografts, as well as in GBMs from human patients. We also showed that the rewired cancer-cell metabolism resulting from VDAC1 depletion reinforced cell growth arrest and differentiation via alterations in the transcription factors p53, c-Myc, HIF-1α and NF-κB. The decrease in c-Myc, HIF-1α and NF-κB levels was in accord with reduced cell proliferation, whereas increased p53 expression promoted differentiation. Thus, upon metabolic re-programing induced by VDAC1 depletion, the levels of pro-apoptotic proteins associated with cell growth decreased, while those connected to cell differentiation increased, converting GBM cells into astrocyte- and neuron-like cells. The results reveal that in tumors, pro-apoptotic proteins can perform non-apoptotic functions, acting as regulators of cell growth and differentiation, making these molecules potential new targets for cancer therapy. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi.
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Affiliation(s)
- Tasleem Arif
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Yakov Krelin
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Varda Shoshan-Barmatz
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
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11
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Ding AX, Sun G, Argaw YG, Wong JO, Easwaran S, Montell DJ. CasExpress reveals widespread and diverse patterns of cell survival of caspase-3 activation during development in vivo. eLife 2016; 5. [PMID: 27058168 PMCID: PMC4865370 DOI: 10.7554/elife.10936] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 04/08/2016] [Indexed: 02/06/2023] Open
Abstract
Caspase-3 carries out the executioner phase of apoptosis, however under special circumstances, cells can survive its activity. To document systematically where and when cells survive caspase-3 activation in vivo, we designed a system, CasExpress, which drives fluorescent protein expression, transiently or permanently, in cells that survive caspase-3 activation in Drosophila. We discovered widespread survival of caspase-3 activity. Distinct spatial and temporal patterns emerged in different tissues. Some cells activated caspase-3 during their normal development in every cell and in every animal without evidence of apoptosis. In other tissues, such as the brain, expression was sporadic both temporally and spatially and overlapped with periods of apoptosis. In adults, reporter expression was evident in a large fraction of cells in most tissues of every animal; however the precise patterns varied. Inhibition of caspase activity in wing discs reduced wing size demonstrating functional significance. The implications of these patterns are discussed. DOI:http://dx.doi.org/10.7554/eLife.10936.001 Every day, individual cells in our body actively decide whether to live or die. There are enzymes called executioner caspases that help cells to die in a carefully controlled process called apoptosis. Although the activation of executioner caspases generally leads to apoptosis, there are some circumstances in which cells are able to survive. Fruit flies are often used in research as models of how animals grow and develop. Ding, Sun et al. set out to find out more about the circumstances in which cells manage to survive caspase activation in fruit flies. The experiments used a new method that results in cells that survive caspase activity producing a fluorescent marker protein. This allowed Ding, Sun et al. to track when and where these events occurred in the flies. Few cells in fruit fly embryos survive the activation of executioner caspase. However, in later stages of development, more and more cells survive this process. Cells in different parts of the body responded differently. For some types of cells, every cell seemed to survive caspase activity with no evidence of apoptosis. In other tissues like the central brain, in which a few cells normally choose to die, some cells occasionally managed to survive the activation of caspases. This rescue from the brink of death was more common than Ding, Sun et al. had anticipated. The next step will be to uncover the molecular mechanisms that enable the cells to survive caspase activity. This knowledge may help us to develop treatments that can promote the survival of useful cells like heart muscle cells and brain cells, or trigger the death of cancer cells. DOI:http://dx.doi.org/10.7554/eLife.10936.002
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Affiliation(s)
- Austin Xun Ding
- Molecular, Cellular and Developmental Biology Department, University of California, Santa Barbara, Santa Barbara, United States.,Department of Biological Chemistry, Center for Cell Dynamics, Johns Hopkins School of Medicine, Baltimore, United States
| | - Gongping Sun
- Molecular, Cellular and Developmental Biology Department, University of California, Santa Barbara, Santa Barbara, United States
| | - Yewubdar G Argaw
- Molecular, Cellular and Developmental Biology Department, University of California, Santa Barbara, Santa Barbara, United States
| | - Jessica O Wong
- Molecular, Cellular and Developmental Biology Department, University of California, Santa Barbara, Santa Barbara, United States
| | - Sreesankar Easwaran
- Molecular, Cellular and Developmental Biology Department, University of California, Santa Barbara, Santa Barbara, United States
| | - Denise J Montell
- Molecular, Cellular and Developmental Biology Department, University of California, Santa Barbara, Santa Barbara, United States.,Department of Biological Chemistry, Center for Cell Dynamics, Johns Hopkins School of Medicine, Baltimore, United States
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BOLKENT Ş, ÖZTAY F, GEZGİNCİ OKTAYOĞLU S, SANCAR BAŞ S, KARATUĞ A. A matter of regeneration and repair: caspases as the key molecules. Turk J Biol 2016. [DOI: 10.3906/biy-1507-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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13
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Age-related intraneuronal accumulation of αII-spectrin breakdown product SBDP120 in the human cerebrum is enhanced in Alzheimer's disease. Exp Gerontol 2015; 69:43-52. [DOI: 10.1016/j.exger.2015.06.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Revised: 05/30/2015] [Accepted: 06/02/2015] [Indexed: 01/09/2023]
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14
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Schouten M, Fratantoni SA, Hubens CJ, Piersma SR, Pham TV, Bielefeld P, Voskuyl RA, Lucassen PJ, Jimenez CR, Fitzsimons CP. MicroRNA-124 and -137 cooperativity controls caspase-3 activity through BCL2L13 in hippocampal neural stem cells. Sci Rep 2015. [PMID: 26207921 PMCID: PMC4513647 DOI: 10.1038/srep12448] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Adult neurogenesis continuously contributes new neurons to hippocampal circuits and the programmed death of a subset of immature cells provides a primary mechanism controlling this contribution. Epileptic seizures induce strong structural changes in the hippocampus, including the induction of adult neurogenesis, changes in gene expression and mitochondrial dysfunction, which may all contribute to epileptogenesis. However, a possible interplay between this factors remains largely unexplored. Here, we investigated gene expression changes in the hippocampal dentate gyrus shortly after prolonged seizures induced by kainic acid, focusing on mitochondrial functions. Using comparative proteomics, we identified networks of proteins differentially expressed shortly after seizure induction, including members of the BCL2 family and other mitochondrial proteins. Within these networks, we report for the first time that the atypical BCL2 protein BCL2L13 controls caspase-3 activity and cytochrome C release in neural stem/progenitor cells. Furthermore, we identify BCL2L13 as a novel target of the cooperative action of microRNA-124 and microRNA-137, both upregulated shortly after seizure induction. This cooperative microRNA-mediated fine-tuning of BCL2L13 expression controls casp3 activity, favoring non-apoptotic caspase-3 functions in NSPC exposed to KA and thereby may contribute to the early neurogenic response to epileptic seizures in the dentate gyrus.
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Affiliation(s)
- Marijn Schouten
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, SciencePark 904, 1098XH, Amsterdam, The Netherlands
| | - Silvina A Fratantoni
- Oncoproteomics Laboratory, Cancer Center, Free University Amsterdam, De Boelelaan 1117, 1081HV, Amsterdam, The Netherlands
| | - Chantal J Hubens
- 1] Division of Pharmacology, LACDR, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands [2] Foundation of Epilepsy Institutes of The Netherlands (SEIN), Achterweg 5, 2103 SW, Heemstede, The Netherlands
| | - Sander R Piersma
- Oncoproteomics Laboratory, Cancer Center, Free University Amsterdam, De Boelelaan 1117, 1081HV, Amsterdam, The Netherlands
| | - Thang V Pham
- Oncoproteomics Laboratory, Cancer Center, Free University Amsterdam, De Boelelaan 1117, 1081HV, Amsterdam, The Netherlands
| | - Pascal Bielefeld
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, SciencePark 904, 1098XH, Amsterdam, The Netherlands
| | - Rob A Voskuyl
- 1] Division of Pharmacology, LACDR, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands [2] Foundation of Epilepsy Institutes of The Netherlands (SEIN), Achterweg 5, 2103 SW, Heemstede, The Netherlands
| | - Paul J Lucassen
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, SciencePark 904, 1098XH, Amsterdam, The Netherlands
| | - Connie R Jimenez
- Oncoproteomics Laboratory, Cancer Center, Free University Amsterdam, De Boelelaan 1117, 1081HV, Amsterdam, The Netherlands
| | - Carlos P Fitzsimons
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, SciencePark 904, 1098XH, Amsterdam, The Netherlands
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Mogi M, Kondo A. Activation of Caspase-8 and Caspase-9 are Required for PC12 Cells Differentiation. J Immunoassay Immunochem 2015; 36:547-58. [DOI: 10.1080/15321819.2015.1017106] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Shalini S, Dorstyn L, Dawar S, Kumar S. Old, new and emerging functions of caspases. Cell Death Differ 2014; 22:526-39. [PMID: 25526085 DOI: 10.1038/cdd.2014.216] [Citation(s) in RCA: 853] [Impact Index Per Article: 85.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 11/13/2014] [Accepted: 11/19/2014] [Indexed: 12/26/2022] Open
Abstract
Caspases are proteases with a well-defined role in apoptosis. However, increasing evidence indicates multiple functions of caspases outside apoptosis. Caspase-1 and caspase-11 have roles in inflammation and mediating inflammatory cell death by pyroptosis. Similarly, caspase-8 has dual role in cell death, mediating both receptor-mediated apoptosis and in its absence, necroptosis. Caspase-8 also functions in maintenance and homeostasis of the adult T-cell population. Caspase-3 has important roles in tissue differentiation, regeneration and neural development in ways that are distinct and do not involve any apoptotic activity. Several other caspases have demonstrated anti-tumor roles. Notable among them are caspase-2, -8 and -14. However, increased caspase-2 and -8 expression in certain types of tumor has also been linked to promoting tumorigenesis. Increased levels of caspase-3 in tumor cells causes apoptosis and secretion of paracrine factors that promotes compensatory proliferation in surrounding normal tissues, tumor cell repopulation and presents a barrier for effective therapeutic strategies. Besides this caspase-2 has emerged as a unique caspase with potential roles in maintaining genomic stability, metabolism, autophagy and aging. The present review focuses on some of these less studied and emerging functions of mammalian caspases.
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Affiliation(s)
- S Shalini
- Centre for Cancer Biology, University of South Australia, Adelaide, SA 5001, Australia
| | - L Dorstyn
- Centre for Cancer Biology, University of South Australia, Adelaide, SA 5001, Australia
| | - S Dawar
- Centre for Cancer Biology, University of South Australia, Adelaide, SA 5001, Australia
| | - S Kumar
- Centre for Cancer Biology, University of South Australia, Adelaide, SA 5001, Australia
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Fan W, Dai Y, Xu H, Zhu X, Cai P, Wang L, Sun C, Hu C, Zheng P, Zhao BQ. Caspase-3 modulates regenerative response after stroke. Stem Cells 2014; 32:473-86. [PMID: 23939807 DOI: 10.1002/stem.1503] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 07/28/2013] [Accepted: 07/31/2013] [Indexed: 12/27/2022]
Abstract
Stroke is a leading cause of long-lasting disability in humans. However, currently there are still no effective therapies available for promoting stroke recovery. Recent studies have shown that the adult brain has the capacity to regenerate neurons after stroke. Although this neurogenic response may be functionally important for brain repair after injury, the mechanisms underlying stroke-induced neurogenesis are not known. Caspase-3 is a major executioner and has been identified as a key mediator of neuronal death in the acute stage of stroke. Recently, however, accumulating data indicate that caspase-3 also participates in various biological processes that do not cause cell death. Here, we show that cleaved caspase-3 was increased in newborn neuronal precursor cells (NPCs) in the subventricular zone (SVZ) and the dentate gyrus during the period of stroke recovery, with no evidence of apoptosis. We observed that cleaved caspase-3 was expressed by NPCs and limited its self-renewal without triggering apoptosis in cultured NPCs from the SVZ of ischemic mice. Moreover, we revealed that caspase-3 negatively regulated the proliferation of NPCs through reducing the phosphorylation of Akt. Importantly, we demonstrated that peptide inhibition of caspase-3 activity significantly promoted the proliferation and migration of SVZ NPCs and resulted in a significant increase in subsequent neuronal regeneration and functional recovery after stroke. Together, our data identify a previously unknown caspase-3-dependent mechanism that constrains stroke-induced endogenous neurogenesis and should revitalize interest in targeting caspase-3 for treatment of stroke.
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Affiliation(s)
- Wenying Fan
- State Key Laboratory of Medical Neurobiology, Shanghai Medical College and Institutes of Brain Science, Fudan University, Shanghai, People's Republic of China
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Benitez SG, Castro AE, Patterson SI, Muñoz EM, Seltzer AM. Hypoxic preconditioning differentially affects GABAergic and glutamatergic neuronal cells in the injured cerebellum of the neonatal rat. PLoS One 2014; 9:e102056. [PMID: 25032984 PMCID: PMC4102512 DOI: 10.1371/journal.pone.0102056] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 06/13/2014] [Indexed: 12/13/2022] Open
Abstract
In this study we examined cerebellar alterations in a neonatal rat model of hypoxic-ischemic brain injury with or without hypoxic preconditioning (Pc). Between postnatal days 7 and 15, the cerebellum is still undergoing intense cellular proliferation, differentiation and migration, dendritogenesis and synaptogenesis. The expression of glutamate decarboxylase 1 (GAD67) and the differentiation factor NeuroD1 were examined as markers of Purkinje and granule cells, respectively. We applied quantitative immunohistochemistry to sagittal cerebellar slices, and Western blot analysis of whole cerebella obtained from control (C) rats and rats submitted to Pc, hypoxia-ischemia (L) and a combination of both treatments (PcL). We found that either hypoxia-ischemia or Pc perturbed the granule cells in the posterior lobes, affecting their migration and final placement in the internal granular layer. These effects were partially attenuated when the Pc was delivered prior to the hypoxia-ischemia. Interestingly, whole nuclear NeuroD1 levels in Pc animals were comparable to those in the C rats. However, a subset of Purkinje cells that were severely affected by the hypoxic-ischemic insult—showing signs of neuronal distress at the levels of the nucleus, cytoplasm and dendritic arborization—were not protected by Pc. A monoclonal antibody specific for GAD67 revealed a three-band pattern in cytoplasmic extracts from whole P15 cerebella. A ∼110 kDa band, interpreted as a potential homodimer of a truncated form of GAD67, was reduced in Pc and L groups while its levels were close to the control animals in PcL rats. Additionally we demonstrated differential glial responses depending on the treatment, including astrogliosis in hypoxiated cerebella and a selective effect of hypoxia-ischemia on the vimentin-immunolabeled intermediate filaments of the Bergmann glia. Thus, while both glutamatergic and GABAergic cerebellar neurons are compromised by the hypoxic-ischemic insult, the former are protected by a preconditioning hypoxia while the latter are not.
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Affiliation(s)
- Sergio G Benitez
- Laboratory of Neurobiology: Chronobiology Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Analía E Castro
- Laboratory of Neurobiology: Chronobiology Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Sean I Patterson
- Traumatic and Toxic Lesions in the Nervous System Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Estela M Muñoz
- Laboratory of Neurobiology: Chronobiology Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Alicia M Seltzer
- Neonatal Brain Development Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
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Caspase-3 and RasGAP: a stress-sensing survival/demise switch. Trends Cell Biol 2013; 24:83-9. [PMID: 24007977 DOI: 10.1016/j.tcb.2013.08.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 08/02/2013] [Accepted: 08/05/2013] [Indexed: 12/31/2022]
Abstract
The final decision on cell fate, survival versus cell death, relies on complex and tightly regulated checkpoint mechanisms. The caspase-3 protease is a predominant player in the execution of apoptosis. However, recent progress has shown that this protease paradoxically can also protect cells from death. Here, we discuss the underappreciated, protective, and prosurvival role of caspase-3 and detail the evidence showing that caspase-3, through differential processing of p120 Ras GTPase-activating protein (RasGAP), can modulate a given set of proteins to generate, depending on the intensity of the input signals, opposite outcomes (survival vs death).
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20
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Seelke AMH, Dooley JC, Krubitzer LA. Differential changes in the cellular composition of the developing marsupial brain. J Comp Neurol 2013; 521:2602-20. [PMID: 23322491 PMCID: PMC3934569 DOI: 10.1002/cne.23301] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2012] [Revised: 09/18/2012] [Accepted: 01/04/2013] [Indexed: 12/27/2022]
Abstract
Throughout development both the body and the brain change at remarkable rates. Specifically, the number of cells in the brain undergoes dramatic nonlinear changes, first exponentially increasing in cell number and then decreasing in cell number. Different cell types, such as neurons and glia, undergo these changes at different stages of development. The current investigation used the isotropic fractionator method to examine the changes in cellular composition at multiple developmental milestones in the short-tailed opossum, Monodelphis domestica. Here we report several novel findings concerning marsupial brain development and organization. First, during the later stages of neurogenesis (P18), neurons make up most of the cells in the neocortex, although the total number of neurons remains the same throughout the life span. In contrast, in the subcortical regions, the number of neurons decreases dramatically after P18, and a converse relationship is observed for nonneuronal cells. In the cerebellum, the total number of cells gradually increases until P180 and then remains constant, and then the number of neurons is consistent across the developmental ages examined. For the three major structures examined, neuronal density and the percentage of neurons within a structure are highest during neurogenesis and then decrease after this point. Finally, the total number of neurons in the opossum brain is relatively low compared with other small-brained mammals such as mice. The relatively low number of neurons and correspondingly high number of nonneurons suggests that in the marsupial brain nonneurons may play a significant role in signal processing.
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Affiliation(s)
- Adele M H Seelke
- Center for Neuroscience, University of California, Davis, Davis, California 95618, USA
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21
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Sawant DA, Tharakan B, Tobin RP, Reilly J, Hunter FA, Newell MK, Smythe WR, Childs EW. Microvascular endothelial cell hyperpermeability induced by endogenous caspase 3 activator staurosporine. J Trauma Acute Care Surg 2013; 74:516-23. [PMID: 23354245 DOI: 10.1097/ta.0b013e31827a0620] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Microvascular hyperpermeability following conditions such as hemorrhagic shock occurs mainly owing to disruption of the adherens junctional protein complex in endothelial cells. The objective of this study was to examine the action of staurosporine, a potent activator of endogenous caspase 3 on the adherens junction and the cellular pathway through which it causes possible endothelial cell barrier dysfunction. METHODS Rat lung microvascular endothelial cell (RLMEC) permeability was measured by fluorescein isothiocyanate-albumin flux across the monolayer in a Transwell plate. Integrity of the endothelial cell adherens junctions was studied using immunofluorescence of β-catenin and vascular endothelial-cadherin. Mitochondrial reactive oxygen species formation was determined by using dihydrorhodamine 123 and mitochondrial transmembrane potential by JC-1 fluorescent probe and flow cytometry. Caspase 3 enzyme activity was assayed fluorometrically. Cell death assay in RLMECs was performed using propidium iodide staining and analyzed by flow cytometry. RESULTS Staurosporine (1 µM)-treated RLMEC monolayers showed significant increase in permeability, which was decreased by pretreatment with caspase 3 specific inhibitor, Z-DEVD-FMK (p < 0.05). Immunofluorescence studies showed staurosporine induced disruption of the adherens junction, which was reversed by Z-DEVD-FMK. Staurosporine treatment led to an increase in mitochondrial reactive oxygen species formation and a decrease in mitochondrial transmembrane potential. Furthermore, staurosporine induced a significant increase in caspase 3 activity (p < 0.05) but not cell death in RLMECs (p < 0.05). CONCLUSION Staurosporine-induced disruption of the adherens junction and microvascular endothelial cell hyperpermeability is associated with the activation of mitochondrial "intrinsic" apoptotic signaling cascade but without causing endothelial cell death. Our results suggest that prevention of mitochondrial-mediated activation of caspase 3 has therapeutic potential against microvascular hyperpermeability.
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Affiliation(s)
- Devendra A Sawant
- Department of Surgery, Texas A&M Health Science Center College of Medicine and Scott and White Health Care, Temple, Texas, USA
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22
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Chang L, Zhang X, Liu W, Song Y, Gao X, Ling W, Wu Y. Immunoreactivity of Ki-67/β-tubulin and immunocolocalization with active caspase-3 in rat dentate gyrus during postnatal development. J Chem Neuroanat 2012; 46:10-8. [PMID: 22959929 DOI: 10.1016/j.jchemneu.2012.08.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Revised: 08/25/2012] [Accepted: 08/25/2012] [Indexed: 11/30/2022]
Abstract
This study was based on our previous report that the expression of active caspase-3 kept at a high level in dentate gyrus during postnatal development, which is not related to an apoptotic event. We addressed the hypothesis that the active caspase-3 expression may be related to a nonapoptotic role in the regulation of the cell cycle and differentiation or other physiological functions. To confirm this hypothesis, through a temporal investigation from postnatal day (P) 0, 4, 7, 10, 14, 21, 28, to 56, based on immunofluorescent method, we dual labeled active caspase-3 with Ki-67 or β-tubulin in the dentate gyrus. Our results showed a minority of active caspase-3 positive cells were colabeled with the proliferation marker Ki-67 in stratum moleculare (MOL), granular cell layer (GCL), subgranular zone (SGZ) and polymorphic stratum (POLY) from P0 to P14, and the colabeled cells decreased gradually with age. From P21 to P56, the colocalization of the two proteins was mainly focused on SGZ. There was a positive correlation between the positive cells of active caspase-3 with that of Ki-67. In addition, an extensive colocalization between active caspase-3 and β-tubulin was observed at all the age groups. There was a strong positive correlation between the intensity of active caspase-3 in GCL with that of β-tubulin in MOL, GCL and POLY of dentate gyrus and the stratum lucidum of CA3. Our data raised the possibility of a nonapoptotic role of active caspase-3 in dentate gyrus, which may be partly associated with cellular proliferation and differentiation, and also may be related to neurite outgrowth, axonal transport, or dendrite elongation of granular cells during postnatal development.
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Affiliation(s)
- Lirong Chang
- Department of Anatomy, Capital Medical University, Beijing, China
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23
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Chronic lead exposure reduces doublecortin-expressing immature neurons in young adult guinea pig cerebral cortex. BMC Neurosci 2012; 13:82. [PMID: 22812564 PMCID: PMC3444321 DOI: 10.1186/1471-2202-13-82] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 07/06/2012] [Indexed: 01/08/2023] Open
Abstract
Background Chronic lead (Pb) poisoning remains an environmental risk especially for the pediatric population, and it may affect brain development. Immature neurons expressing doublecortin (DCX+) exist around cortical layer II in various mammals, including adult guinea pigs and humans. Using young adult guinea pigs as an experimental model, the present study explored if chronic Pb exposure affects cortical DCX + immature neurons and those around the subventricular and subgranular zones (SVZ, SGZ). Results Two month-old guinea pigs were treated with 0.2% lead acetate in drinking water for 2, 4 and 6 months. Blood Pb levels in these animals reached 10.27 ± 0.62, 16.25 ± 0.78 and 19.03 ± 0.86 μg/dL at the above time points, respectively, relative to ~3 μg/dL in vehicle controls. The density of DCX + neurons was significantly reduced around cortical layer II, SVZ and SGZ in Pb-treated animals surviving 4 and 6 months relative to controls. Bromodeoxyuridine (BrdU) pulse-chasing studies failed to find cellular colocalization of this DNA synthesis indicator in DCX + cells around layer II in Pb-treated and control animals. These cortical immature neurons were not found to coexist with active caspase-3 or Fluoro-Jade C labeling. Conclusion Chronic Pb exposure can lead to significant reduction in the number of the immature neurons around cortical layer II and in the conventional neurogenic sites in young adult guinea pigs. No direct evidence could be identified to link the reduced cortical DCX expression with alteration in local neurogenesis or neuronal death.
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Cai Y, Zhu HX, Li JM, Luo XG, Patrylo PR, Rose GM, Streeter J, Hayes R, Wang KKW, Yan XX, Jeromin A. Age-related intraneuronal elevation of αII-spectrin breakdown product SBDP120 in rodent forebrain accelerates in 3×Tg-AD mice. PLoS One 2012; 7:e37599. [PMID: 22723836 PMCID: PMC3377681 DOI: 10.1371/journal.pone.0037599] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Accepted: 04/23/2012] [Indexed: 11/24/2022] Open
Abstract
Spectrins line the intracellular surface of plasmalemma and play a critical role in supporting cytoskeletal stability and flexibility. Spectrins can be proteolytically degraded by calpains and caspases, yielding breakdown products (SBDPs) of various molecular sizes, with SBDP120 being largely derived from caspase-3 cleavage. SBDPs are putative biomarkers for traumatic brain injury. The levels of SBDPs also elevate in the brain during aging and perhaps in Alzheimer’s disease (AD), although the cellular basis for this change is currently unclear. Here we examined age-related SBDP120 alteration in forebrain neurons in rats and in the triple transgenic model of AD (3×Tg-AD) relative to non-transgenic controls. SBDP120 immunoreactivity (IR) was found in cortical neuronal somata in aged rats, and was prominent in the proximal dendrites of the olfactory bulb mitral cells. Western blot and densitometric analyses in wild-type mice revealed an age-related elevation of intraneuronal SBDP120 in the forebrain which was more robust in their 3×Tg-AD counterparts. The intraneuronal SBDP120 occurrence was not spatiotemporally correlated with transgenic amyloid precursor protein (APP) expression, β-amyloid plaque development, or phosphorylated tau expression over various forebrain regions or lamina. No microscopically detectable in situ activated caspase-3 was found in the nuclei of SBDP120-containing neurons. The present study demonstrates the age-dependent intraneuronal presence of an αII-spectrin cleavage fragment in mammalian forebrain which is exacerbated in a transgenic model of AD. This novel neuronal alteration indicates that impairments in membrane protein metabolism, possibly due to neuronal calcium mishandling and/or enhancement of calcium sensitive proteolysis, occur during aging and in transgenic AD mice.
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Affiliation(s)
- Yan Cai
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, Hunan, China
| | - Hai-Xia Zhu
- Department of Neurology, The Third Xiangya Hospital, Changsha, Hunan, China
| | - Jian-Ming Li
- Neuroscience Research Center, Changsha Medical University, Changsha, Hunan, China
| | - Xue-Gang Luo
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, Hunan, China
| | - Peter R. Patrylo
- Departments of Anatomy & Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois, United States of America
- Center for Integrated Research in Cognitive and Neural Sciences, Southern Illinois University School of Medicine, Carbondale, Illinois, United States of America
| | - Gregory M. Rose
- Departments of Anatomy & Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois, United States of America
- Center for Integrated Research in Cognitive and Neural Sciences, Southern Illinois University School of Medicine, Carbondale, Illinois, United States of America
| | | | - Ron Hayes
- Banyan Biomarkers, Alachua, Florida, United States of America
| | | | - Xiao-Xin Yan
- Department of Anatomy and Neurobiology, Central South University Xiangya Medical School, Changsha, Hunan, China
- Center for Integrated Research in Cognitive and Neural Sciences, Southern Illinois University School of Medicine, Carbondale, Illinois, United States of America
- * E-mail: (XXY); (AJ)
| | - Andreas Jeromin
- Banyan Biomarkers, Alachua, Florida, United States of America
- * E-mail: (XXY); (AJ)
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Mast TG, Fadool DA. Mature and precursor brain-derived neurotrophic factor have individual roles in the mouse olfactory bulb. PLoS One 2012; 7:e31978. [PMID: 22363780 PMCID: PMC3283713 DOI: 10.1371/journal.pone.0031978] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Accepted: 01/16/2012] [Indexed: 11/18/2022] Open
Abstract
Background Sensory deprivation induces dramatic morphological and neurochemical changes in the olfactory bulb (OB) that are largely restricted to glomerular and granule layer interneurons. Mitral cells, pyramidal-like neurons, are resistant to sensory-deprivation-induced changes and are associated with the precursor to brain-derived neurotrophic factor (proBDNF); here, we investigate its unknown function in the adult mouse OB. Principal Findings As determined using brain-slice electrophysiology in a whole-cell configuration, brain-derived neurotrophic factor (BDNF), but not proBDNF, increased mitral cell excitability. BDNF increased mitral cell action potential firing frequency and decreased interspike interval in response to current injection. In a separate set of experiments, intranasal delivery of neurotrophic factors to awake, adult mice was performed to induce sustained interneuron neurochemical changes. ProBDNF, but not BDNF, increased activated-caspase 3 and reduced tyrosine hydroxylase immunoreactivity in OB glomerular interneurons. In a parallel set of experiments, short-term sensory deprivation produced by unilateral naris occlusion generated an identical phenotype. Conclusions Our results indicate that only mature BDNF increases mitral cell excitability whereas proBDNF remains ineffective. Our demonstration that proBDNF activates an apoptotic marker in vivo is the first for any proneurotrophin and establishes a role for proBDNF in a model of neuronal plasticity.
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Affiliation(s)
- Thomas Gerald Mast
- Department of Biological Science, The Florida State University, Tallahassee, Florida, United States of America.
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Yakovlev AA, Gulyaeva NV. Pleiotropic functions of brain proteinases: Methodological considerations and search for caspase substrates. BIOCHEMISTRY (MOSCOW) 2011; 76:1079-86. [DOI: 10.1134/s0006297911100014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Northington FJ, Chavez-Valdez R, Martin LJ. Neuronal cell death in neonatal hypoxia-ischemia. Ann Neurol 2011; 69:743-58. [PMID: 21520238 DOI: 10.1002/ana.22419] [Citation(s) in RCA: 269] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Perinatal hypoxic-ischemic encephalopathy (HIE) is a significant cause of mortality and morbidity in infants and young children. Therapeutic opportunities are very limited for neonatal and pediatric HIE. Specific neural systems and populations of cells are selectively vulnerable in HIE; however, the mechanisms of degeneration are unresolved. These mechanisms involve oxidative stress, excitotoxicity, inflammation, and the activation of several different cell death pathways. Decades ago the structural and mechanistic basis of the cellular degeneration in HIE was thought to be necrosis. Subsequently, largely due to advances in cell biology and to experimental animal studies, emphasis has been switched to apoptosis or autophagy mediated by programmed cell death (PCD) mechanisms as important forms of degeneration in HIE. We have conceptualized based on morphological and biochemical data that this degeneration is better classified according to an apoptosis-necrosis cell death continuum and that programmed cell necrosis has prominent contribution in the neurodegeneration of HIE in animal models. It is likely that neonatal HIE evolves through many cell death chreodes influenced by the dynamic injury landscape. The relevant injury mechanisms remain to be determined in human neonatal HIE, though preliminary work suggests a complexity in the cell death mechanisms greater than that anticipated from experimental animal models. The accurate identification of the various cell death chreodes and their mechanisms unfolding within the immature brain matrix could provide fresh insight for developing meaningful therapies for neonatal and pediatric HIE.
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Affiliation(s)
- Frances J Northington
- Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
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Armentano M, Canalia N, Crociara P, Bonfanti L. Culturing conditions remarkably affect viability and organization of mouse subventricular zone in ex vivo cultured forebrain slices. J Neurosci Methods 2011; 197:65-81. [DOI: 10.1016/j.jneumeth.2011.01.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Revised: 12/29/2010] [Accepted: 01/29/2011] [Indexed: 10/18/2022]
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Contribution of caspase(s) to the cell cycle regulation at mitotic phase. PLoS One 2011; 6:e18449. [PMID: 21479177 PMCID: PMC3068168 DOI: 10.1371/journal.pone.0018449] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 03/01/2011] [Indexed: 11/26/2022] Open
Abstract
Caspases have been suggested to contribute to not only apoptosis regulation but also non-apoptotic cellular phenomena. Recently, we have reported the involvement of caspase-7 to the cell cycle progression at mitotic phase by knockdown of caspase-7 using small interfering RNAs and short hairpin RNA. Here we showed that chemically synthesized broad-spectrum caspase inhibitors, which have been used to suppress apoptosis, prevented the cell proliferation in a dose-dependent manner, and that the subtype-specific peptide-based caspase inhibitor for caspase-3 and -7, but not for caspase-9, inhibited cell proliferation. It was also indicated that the BIR2 domain of X-linked inhibitor of apoptosis protein, functioning as an inhibitor for caspase-3 and -7, but not the BIR3 domain which plays as a caspase-9 inhibitor, induced cell cycle arrest. Furthermore, flow cytometry revealed that the cells treated with caspase inhibitors arrested at G2/M phase. By using HeLa.S-Fucci (fluorescent ubiquitination-based cell cycle indicator) cells, the prevention of the cell proliferation by caspase inhibitors induced cell cycle arrest at mitotic phase accompanying the accumulation of the substrates for APC/C, suggesting the impairment of the APC/C activity at the transition from M to G1 phases. These results indicate that caspase(s) contribute to the cell cycle regulation at mitotic phase.
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Increased BrdU incorporation reflecting DNA repair, neuronal de-differentiation or possible neurogenesis in the adult cochlear nucleus following bilateral cochlear lesions in the rat. Exp Brain Res 2010; 210:477-87. [DOI: 10.1007/s00221-010-2491-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Accepted: 11/03/2010] [Indexed: 02/06/2023]
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Jin Z, Wallace L, Harper SQ, Yang J. PP2A:B56{epsilon}, a substrate of caspase-3, regulates p53-dependent and p53-independent apoptosis during development. J Biol Chem 2010; 285:34493-502. [PMID: 20807766 DOI: 10.1074/jbc.m110.169581] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Protein phosphatase 2A (PP2A) is one of the most abundantly expressed serine/threonine protein phosphatases. A large body of evidence suggests that PP2A is a tumor suppressor and plays critical roles in regulating apoptosis. PP2A is a heterotrimeric protein complex. Its substrate specificity, localization, and activity are regulated by regulatory subunits of PP2A. A recent study has demonstrated that single nucleotide polymorphism in B56ε (PPP2R5E), a B56 family regulatory subunit of PP2A, is associated with human soft tissue sarcoma. This raises the possibility that B56ε is involved in tumorigenesis and plays important roles in regulating apoptosis. However, this hypothesis has not been tested experimentally. Our previous studies revealed that B56ε regulates a number of developmental signaling pathways during early embryonic patterning. Here we report novel functions of B56ε in regulating apoptosis. We provide evidence that B56ε has both anti- and pro-apoptotic functions. B56ε suppresses p53-independent apoptosis during neural development, but triggers p53-dependent apoptosis. Mechanistically, B56ε regulates the p53-dependent apoptotic pathway solely through controlling the stability of p53 protein. In addition to its function in regulating apoptosis, we show that B56ε undergoes proteolytic cleavage. The cleavage of B56ε is mediated by caspase-3 and occurs on the carboxyl side of an evolutionarily conserved N-terminal "DKXD" motif. These results demonstrate that B56ε, a substrate of caspase-3, is an essential regulator of apoptosis. So far, we have identified an alternative translation isoform and a caspase cleavage product of B56ε. The significance of post-transcriptional regulation of B56ε is discussed.
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Affiliation(s)
- Zhigang Jin
- Department of Pediatrics, Research Institute at Nationwide Children's Hospital, Ohio State University, Columbus, Ohio 43205, USA
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Nadzialek S, Pigneur LM, Wéron B, Kestemont P. Bcl-2 and Caspase 3 mRNA levels in the testes of gudgeon, Gobio gobio, exposed to ethinylestradiol (EE2). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2010; 98:304-310. [PMID: 20356636 DOI: 10.1016/j.aquatox.2010.02.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2009] [Revised: 02/19/2010] [Accepted: 02/23/2010] [Indexed: 05/29/2023]
Abstract
Apoptosis inhibition has been reported in the male reproductive tract of teleost fish exposed to 17beta-estrogen or estrogen-like compounds. In order to understand the molecular mechanisms of cell death inhibition, this study examined 2 genes involved in the apoptotic pathway, Bcl-2 and Caspase 3, an anti-apoptotic and a pro-apoptotic genes, respectively. Partial cDNA sequences of Bcl-2 and Caspase 3 were cloned from gudgeon (Gobio gobio), a common European cyprinid fish. To follow mRNA levels of Bcl-2 and Caspase 3 under xenoestrogen exposure, we first performed an in vitro experiment on fish testis exposed to the most potent xenoestrogen found in the environment, ethinylestradiol (EE2). We further studied mRNA expression of both genes in the testis of fish exposed to xenoestrogens in situ. In the in vitro experiment, fragments of gudgeon testis were exposed for 21 days to 10(-3), 10(-2), 10(-1), 1 and 10 microg/L of EE2, as well as to positive (10(-1) microg/L of E2) and ethanol control medium. Results showed a significant induction of Bcl-2 mRNA at 10(-1) microg/L (p<0.05). Surprisingly, Caspase 3, a cell death effector, displayed the same profile as observed for the anti-apoptotic gene Bcl-2. In the experiment on wild gudgeon exposed from birth to an estrogenic sewage treatment plant effluent, the mRNA expression of Bcl-2 and Caspase 3 in feminized fish (ovotestis) was not significantly different due to high variability of expression between individuals. At the current state of knowledge on spermatogenesis disruption in teleost fish, in vitro studies seem better adapted than in situ investigations to enlighten the molecular pathway of apoptosis inhibition in testis exposed to xenoestrogens.
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Affiliation(s)
- Stéphanie Nadzialek
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium
| | - Lise-Marie Pigneur
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium
| | - Benjamin Wéron
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium
| | - Patrick Kestemont
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium.
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Abstract
Alzheimer’s disease (AD), Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS) are the most common human adult-onset neurodegenerative diseases. They are characterized by prominent age-related neurodegeneration in selectively vulnerable neural systems. Some forms of AD, PD, and ALS are inherited, and genes causing these diseases have been identified. Nevertheless, the mechanisms of the neuronal cell death are unresolved. Morphological, biochemical, genetic, as well as cell and animal model studies reveal that mitochondria could have roles in this neurodegeneration. The functions and properties of mitochondria might render subsets of selectively vulnerable neurons intrinsically susceptible to cellular aging and stress and overlying genetic variations, triggering neurodegeneration according to a cell death matrix theory. In AD, alterations in enzymes involved in oxidative phosphorylation, oxidative damage, and mitochondrial binding of Aβ and amyloid precursor protein have been reported. In PD, mutations in putative mitochondrial proteins have been identified and mitochondrial DNA mutations have been found in neurons in the substantia nigra. In ALS, changes occur in mitochondrial respiratory chain enzymes and mitochondrial cell death proteins. Transgenic mouse models of human neurodegenerative disease are beginning to reveal possible principles governing the biology of selective neuronal vulnerability that implicate mitochondria and the mitochondrial permeability transition pore. This review summarizes how mitochondrial pathobiology might contribute to neuronal death in AD, PD, and ALS and could serve as a target for drug therapy.
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Finckbone V, Oomman SK, Strahlendorf HK, Strahlendorf JC. Regional differences in the temporal expression of non-apoptotic caspase-3-positive bergmann glial cells in the developing rat cerebellum. Front Neuroanat 2009; 3:3. [PMID: 19503747 PMCID: PMC2691149 DOI: 10.3389/neuro.05.003.2009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2009] [Accepted: 05/04/2009] [Indexed: 01/22/2023] Open
Abstract
Although caspases have been intimately linked to apoptotic events, some of the pro-apoptotic caspases also may regulate differentiation. We previously demonstrated that active caspase-3 is expressed and has an apparent non-apoptotic function during the development of cerebellar Bergmann glia. The current study seeks to further correlate active/cleaved caspase-3 expression with the developmental phenotype of Bergmann glia by examining regional differences in the temporal pattern of expression of cleaved caspase-3 immunoreactivity in lobules of the cerebellar vermis. In general, we found that the expression pattern of cleaved caspase-3 corresponds to the reported developmental temporal profile of the lobes and that its levels peak at 15 days and declines thereafter. Compared to intermediate or late maturing lobules, early maturing lobules had higher levels of active caspase-3 at earlier postnatal times. This period of postnatal development is precisely the time during which Bergmann glia initiate differentiation.
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Affiliation(s)
- Velvetlee Finckbone
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center Lubbock, TX, USA
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35
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Lieberman JA, Bymaster FP, Meltzer HY, Deutch AY, Duncan GE, Marx CE, Aprille JR, Dwyer DS, Li XM, Mahadik SP, Duman RS, Porter JH, Modica-Napolitano JS, Newton SS, Csernansky JG. Antipsychotic drugs: comparison in animal models of efficacy, neurotransmitter regulation, and neuroprotection. Pharmacol Rev 2009; 60:358-403. [PMID: 18922967 DOI: 10.1124/pr.107.00107] [Citation(s) in RCA: 172] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Various lines of evidence indicate the presence of progressive pathophysiological processes occurring within the brains of patients with schizophrenia. By modulating chemical neurotransmission, antipsychotic drugs may influence a variety of functions regulating neuronal resilience and viability and have the potential for neuroprotection. This article reviews the current literature describing preclinical and clinical studies that evaluate the efficacy of antipsychotic drugs, their mechanism of action and the potential of first- and second-generation antipsychotic drugs to exert effects on cellular processes that may be neuroprotective in schizophrenia. The evidence to date suggests that although all antipsychotic drugs have the ability to reduce psychotic symptoms via D(2) receptor antagonism, some antipsychotics may differ in other pharmacological properties and their capacities to mitigate and possibly reverse cellular processes that may underlie the pathophysiology of schizophrenia.
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Affiliation(s)
- Jeffrey A Lieberman
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, 1051 Riverside Dr., Unit 4, New York, NY 10032, USA.
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García-Cáceres C, Lechuga-Sancho A, Argente J, Frago LM, Chowen JA. Death of hypothalamic astrocytes in poorly controlled diabetic rats is associated with nuclear translocation of apoptosis inducing factor. J Neuroendocrinol 2008; 20:1348-60. [PMID: 19094082 DOI: 10.1111/j.1365-2826.2008.01795.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Astrocytes in the hypothalamus of poorly controlled diabetic rats are reduced in number, due to increased apoptosis and decreased proliferation, and undergo morphological changes, including a decrease in projections. These changes are associated with modifications in synaptic proteins and most likely affect neuroendocrine signalling and function. The present study aimed to determine the intracellular mechanisms underlying this increase in hypothalamic cell death. Adult male Wistar rats were injected with streptozotocin (70 mg/kg, i.p) and controls received vehicle. Rats were killed at 1, 4, 6 and 8 weeks after diabetes onset (glycaemia > 300 mg/dl). Cell death, as detected by enzyme-linked immunosorbent assay, increased at 4 weeks of diabetes. Immunohistochemistry and terminal dUTP nick-end labelling (TUNEL) assays indicated that these cells corresponded to glial fibrillary acidic protein (GFAP) positive cells. No significant change in fragmentation of caspases 2, 3, 6, 7, 8, 9, or 12 was observed with western blot analysis. However, enzymatic assays indicated that caspase 3 activity increased significantly after 1 week of diabetes and decreased below control levels thereafter. In the hypothalamus, cell bodies lining the third ventricle, fibres radiating from the third ventricle and GFAP positive cells expressed fragmented caspase 3, with this labelling increasing at 1 week of diabetes. However, because no nuclear labelling was observed and this increase in activity did not correlate temporally with the increased cell death, this caspase may not be involved in astrocyte death. By contrast, nuclear translocation of apoptosis inducing factor (AIF) increased significantly in astrocytes in parallel with the increase in death and AIF was found in TUNEL positive cells. Thus, nuclear translocation of AIF could underlie the increased death, whereas fragmentation of caspase 3 could be associated with the morphological changes found in hypothalamic astrocytes of diabetic rats.
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Affiliation(s)
- C García-Cáceres
- Hospital Infantil Universitario Niño Jesús, Servicio de Endocrinología, Madrid, Spain
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Hashimoto T, Yamauchi L, Hunter T, Kikkawa U, Kamada S. Possible involvement of caspase-7 in cell cycle progression at mitosis. Genes Cells 2008; 13:609-21. [PMID: 18459962 DOI: 10.1111/j.1365-2443.2008.01192.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Caspases are suggested to play essential roles not only in apoptotic but also in non-apoptotic functions. However, the contribution of caspases to the cell cycle regulation is unclear. Here we found that caspases including caspase-3, caspase-7, caspase-8 and caspase-9 were activated during mitosis. Chemically synthesized caspase inhibitors delayed mitotic progression and induced accumulation of mitotic cells, which exhibited abnormal chromatin condensation and incomplete chromosome segregation. Furthermore, knockdown of caspase-7 by using small interfering RNAs resulted in the inhibition of cell proliferation, but knockdown of other caspases did not show a significant effect on cell growth. The expression of short hairpin RNA directed against caspase-7 induced the cell cycle arrest at mitosis, which was rescued by the re-expression of caspase-7 containing silent mutations at the target site for the short hairpin RNA. These results revealed that caspase-7 has a novel role during cell cycle progression at mitosis.
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Affiliation(s)
- Toshiaki Hashimoto
- Biosignal Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
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Lack of pathology in a triple transgenic mouse model of Alzheimer's disease after overexpression of the anti-apoptotic protein Bcl-2. J Neurosci 2008; 28:3051-9. [PMID: 18354008 DOI: 10.1523/jneurosci.5620-07.2008] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Alzheimer's disease (AD) is characterized by the accumulation of plaques containing beta-amyloid (Abeta) and neurofibrillary tangles (NFTs) consisting of modified tau. Although Abeta deposition is thought to precede the formation of NFTs in AD, the molecular steps connecting these two pathologies is not known. Previous studies have suggested that caspase activation plays an important role in promoting the pathology associated with AD. To further understand the contribution of caspases in disease progression, a triple transgenic Alzheimer's mouse model overexpressing the anti-apoptotic protein Bcl-2 was generated. Here we show that overexpression of Bcl-2 limited caspase-9 activation and reduced the caspase cleavage of tau. Moreover, overexpression of Bcl-2 attenuated the processing of APP (amyloid precursor protein) and tau and reduced the number of NFTs and extracellular deposits of Abeta associated with these animals. In addition, overexpression of Bcl-2 in 3xTg-AD mice improved place recognition memory. These findings suggest that the activation of apoptotic pathways may be an early event in AD and contributes to the pathological processes that promote the disease mechanisms underlying AD.
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Xiong K, Luo DW, Patrylo PR, Luo XG, Struble RG, Clough RW, Yan XX. Doublecortin-expressing cells are present in layer II across the adult guinea pig cerebral cortex: partial colocalization with mature interneuron markers. Exp Neurol 2008; 211:271-82. [PMID: 18378231 DOI: 10.1016/j.expneurol.2008.02.003] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Revised: 01/21/2008] [Accepted: 02/06/2008] [Indexed: 02/02/2023]
Abstract
Doublecortin-immunoreactive (DCX+) cells were detected across the allo- and neo-cortical regions in the adult guinea pig cerebrum, localized to layer II specifically at its border with layer I. The density of labeled cells declined with age, whereas no apparent apoptotic activity was detectable over the cortex including layer II. DCX+ cells varied in somal size, labeling intensity, nuclear appearance, and complexity of processes. These cells were often arranged in clusters with cells of similar morphology sometimes packed tightly together. They exhibited complete colocalization with polysialylated neural cell adhesion molecule (PSA-NCAM) and neuron-specific type III beta-tubulin (TuJ1). Medium to large-sized DCX+ cells had well-developed neuritic processes, and expressed neuron-specific nuclear protein (NeuN). Large mature-looking cells with weak DCX reactivity invariably displayed heavy NeuN reactivity, implicating a transitional stage of these labeled cells. These "transitional" cells also consistently exhibited weak reactivity for gamma-aminobutyric acid (GABA), glutamate decarboxylase (GAD67), beta-nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) and neuronal nitric oxide synthase (nNOS), suggestive of them being young GABAergic/nitrinergic interneurons. Our data indicate that DCX+ cells exist widely in the adult guinea pig cerebral cortex, with a predominant localization in upper layer II. The morphological variation and differential expression of neuronal markers in these cells implicate that they might be developing neurons, and that they are probably differentiating into GABAergic interneurons. This population of cells might be involved in interneuron plasticity in the adult mammalian cerebral cortex.
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Affiliation(s)
- Kun Xiong
- Department of Anatomy, Southern Illinois University School of Medicine, 1135 Lincoln Drive, Carbondale, IL 62901, USA
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40
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Gdynia G, Grund K, Eckert A, Bock BC, Funke B, Macher-Goeppinger S, Sieber S, Herold-Mende C, Wiestler B, Wiestler OD, Roth W. Basal Caspase Activity Promotes Migration and Invasiveness in Glioblastoma Cells. Mol Cancer Res 2007; 5:1232-40. [DOI: 10.1158/1541-7786.mcr-07-0343] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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41
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Hörbelt M, Lee SY, Mang HE, Knipe NL, Sado Y, Kribben A, Sutton TA. Acute and chronic microvascular alterations in a mouse model of ischemic acute kidney injury. Am J Physiol Renal Physiol 2007; 293:F688-95. [PMID: 17626153 DOI: 10.1152/ajprenal.00452.2006] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Functional and structural abnormalities in the renal microvasculature are important processes contributing to the pathophysiology of ischemic acute kidney injury (AKI). In this study, we examine the contribution of endothelial cell loss via apoptosis on microvascular permeability and rarefaction in a mouse model of ischemic AKI. Three-dimensional reconstructions of microvascular networks obtained 24 h following acute ischemic injury demonstrate an intact endothelial monolayer in areas of increased microvascular permeability. A 45% decrease in microvascular density was observed 4 wk after acute ischemic injury. Examination of microvascular endothelial cells following acute ischemic injury did not reveal evidence of positive terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling staining at 1, 2, 8, and 16 days following ischemia; however, activation of caspase-3 was evident in endothelial cells following acute ischemic injury. Examination of angiopoietin (Ang) protein expression in the kidney 24 h after ischemic injury revealed an eightfold increase in Ang-1 but no significant change in Ang-2. No significant difference in the expression of vascular endothelial growth factor or Ang-2 was observed 4 wk after ischemic injury, although an almost twofold elevation in Ang-1 was observed. An increase in angiostatic breakdown products of collagen IV was observed at both 24 h and 4 wk after ischemic injury. Taken together, these findings indicate that the loss of endothelial cells following ischemic injury is not a major contributor to altered microvascular permeability, although renal microvascular endothelial cells are vulnerable to the initiation of apoptotic mechanisms following ischemic injury that can ultimately impact microvascular density.
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Affiliation(s)
- Markus Hörbelt
- Division of Nephrology, Department of Medicine and the Indiana Center for Biological Microscopy, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
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42
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Finger TE. Editor's remarks: Chemotopic odorant coding in a mammalian olfactory system, Johnson et al., J Comp Neurol 503:1–34. J Comp Neurol 2007. [DOI: 10.1002/cne.21437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Acarin L, Villapol S, Faiz M, Rohn TT, Castellano B, González B. Caspase-3 activation in astrocytes following postnatal excitotoxic damage correlates with cytoskeletal remodeling but not with cell death or proliferation. Glia 2007; 55:954-65. [PMID: 17487878 DOI: 10.1002/glia.20518] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Caspase-3 has classically been defined as the main executioner of programmed cell death. However, recent data supports the participation of this protease in non-apoptotic cellular events including cell proliferation, cell cycle regulation, and cellular differentiation. In this study, astroglial cleavage of caspase-3 was analyzed following excitotoxic damage in postnatal rats to determine if its presence is associated with apoptotic cell death, cell proliferation, or cytoskeletal remodeling. A well-characterized in vivo model of excitotoxicity was studied, where damage was induced by intracortical injection of N-methyl-D-asparate (NMDA) in postnatal day 9 rats. Our results demonstrate that cleaved caspase-3 was mainly observed in the nucleus of activated astrocytes in the lesioned hemisphere as early as 4 h postlesion and persisted until the glial scar was formed at 7-14 days, and it was not associated with TUNEL labeling. Caspase-3 enzymatic activity was detected at 10 h and 1 day postlesion in astrocytes, and co-localized with caspase-cleaved fragments of glial fibrillary acidic protein (CCP-GFAP). However, at longer survival times, when astroglial hypertrophy was observed, astroglial caspase-3 did not generally correlate with GFAP cleavage, but instead was associated with de novo expression of vimentin. Moreover, astroglial caspase-3 cleavage was not associated with BrdU incorporation. These results provide further evidence for a nontraditional role of caspases in cellular function that is independent of cell death and suggest that caspase activation is important for astroglial cytoskeleton remodeling following cellular injury.
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Affiliation(s)
- Laia Acarin
- Medical Histology, Department of Cell Biology, Physiology and Immunology, Faculty of Medicine and Institute of Neurosciences, Autonomous University of Barcelona, Spain.
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Lamkanfi M, Festjens N, Declercq W, Vanden Berghe T, Vandenabeele P. Caspases in cell survival, proliferation and differentiation. Cell Death Differ 2006; 14:44-55. [PMID: 17053807 DOI: 10.1038/sj.cdd.4402047] [Citation(s) in RCA: 405] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Caspases, a family of evolutionarily, conserved cysteinyl proteases, mediate both apoptosis and inflammation through aspartate-specific cleavage of a wide number of cellular substrates. Most substrates of apoptotic caspases have been conotated with cellular dismantling, while inflammatory caspases mediate the proteolytic activation of inflammatory cytokines. Through detailed functional analysis of conditional caspase-deficient mice or derived cells, caspase biology has been extended to cellular responses such as cell differentiation, proliferation and NF-kappaB activation. Here, we discuss recent data indicating that non-apoptotic functions of caspases involve proteolysis exerted by their catalytic domains as well as non-proteolytic functions exerted by their prodomains. Homotypic oligomerization motifs in the latter mediate the recruitment of adaptors and effectors that modulate NF-kappaB activation. The non-apoptotic functions of caspases suggest that they may become activated independently of--or without--inducing an apoptotic cascade. Moreover, the existence of non-catalytic caspase-like molecules such as human caspase-12, c-FLIP and CARD-only proteins further supports the non-proteolytic functions of caspases in the regulation of cell survival, proliferation, differentiation and inflammation.
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Affiliation(s)
- M Lamkanfi
- Unit of Molecular Signalling and Cell Death, Department for Molecular Biomedical Research, Flanders Interuniversity Institute for Biotechnology (VIB), Ghent University, Ghent (Zwijnaarde), Belgium
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Zeng L, Lu X, Zeng S, Lin Y, Sun Y, Zhang X, Zuo M. Dynamic changes of apoptosis and expression of Bcl-2 family members in the posthatch hippocampus of Bengalese finches. Brain Res 2006; 1107:58-69. [PMID: 16842761 DOI: 10.1016/j.brainres.2006.05.085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2006] [Revised: 05/19/2006] [Accepted: 05/26/2006] [Indexed: 10/24/2022]
Abstract
The hippocampus of songbirds plays an important role in spatial memory, and probably in song learning. Although prolonged neuronal generation and apoptosis are thought to be closely correlated with memory function, natural changes of the number of neurons and in apoptosis in the hippocampus of songbirds have not been fully investigated during development and in the adult. In the current study, we examined developmental changes in the volume and the number of neurons and apoptotic cells in the hippocampus of songbirds (Lonchura striata) from posthatch day (P5) to adulthood. Apoptotic cells were determined by Nissl staining and immunohistochemistry for cleaved caspase-3, a key apoptotic caspase executioner. The expression levels of Bcl-2 family member mRNA and protein, including Bcl-2, Bcl-xL and Bax, were also investigated. Our results indicated that: (1) the hippocampus volume significantly increased from P5 to P60, although the number of neurons remained stable in all studied stages; (2) the number of apoptotic cells was highest at P45, based either on the Nissl staining or on the immunohistochemistry for caspase-3; (3) Bcl-2 mRNA expression was high from P5 to adulthood, while Bax mRNA declined abruptly from P5 to adulthood, and Bcl-x mRNA was high after P45. Bcl-2 protein was only detected at P5 and P15, while detection of Bcl-xL and Bax proteins paralleled levels of mRNA expression. Our study provides detailed changes of apoptosis in the posthatch songbird hippocampus, suggesting an important role for caspase-3 and Bcl-2 family members in hippocampus apoptosis.
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Affiliation(s)
- Lei Zeng
- College of Life Sciences, Beijing Normal University, Beijing 100875, China
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McFarland KN, Wilkes SR, Koss SE, Ravichandran KS, Mandell JW. Neural-specific inactivation of ShcA results in increased embryonic neural progenitor apoptosis and microencephaly. J Neurosci 2006; 26:7885-97. [PMID: 16870734 PMCID: PMC6674223 DOI: 10.1523/jneurosci.3524-05.2006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2005] [Revised: 06/16/2006] [Accepted: 06/18/2006] [Indexed: 01/29/2023] Open
Abstract
Brain size is precisely regulated during development and involves coordination of neural progenitor cell proliferation, differentiation, and survival. The adapter protein ShcA transmits signals from receptor tyrosine kinases via MAPK (mitogen-activated protein kinase)/ERK (extracellular signal-regulated kinase) and PI3K (phosphatidylinositol 3-kinase)/Akt signaling pathways. In the CNS, ShcA expression is high during embryonic development but diminishes as cells differentiate and switches to ShcB/Sck/Sli and ShcC/N-Shc/Rai. To directly test ShcA function in brain development, we used Cre/lox technology to express a dominant-negative form of ShcA (ShcFFF) in nestin-expressing neural progenitors. ShcFFF-expressing mice display microencephaly with brain weights reduced to 50% of littermate controls throughout postnatal and adult life. The cerebrum appeared most severely affected, but the gross architecture of the brain is normal. Body weight was mildly affected with a delay in reaching mature weight. At a mechanistic level, the ShcFFF microencephaly phenotype appears to be primarily attributable to elevated apoptosis levels throughout the brain from embryonic day 10.5 (E10.5) to E12, which declined by E14.5. Apoptosis remained at normal basal levels throughout postnatal development. Proliferation indices were not significantly altered in the embryonic neuroepithelium or within the postnatal subventricular zone. In another approach with the same nestin-Cre transgene, conditional deletion of ShcA in mice with a homozygous floxed shc1 locus also showed a similar microencephaly phenotype. Together, these data suggest a critical role for ShcA in neural progenitor survival signaling and in regulating brain size.
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Lamkanfi M, Declercq W, Vanden Berghe T, Vandenabeele P. Caspases leave the beaten track: caspase-mediated activation of NF-kappaB. ACTA ACUST UNITED AC 2006; 173:165-71. [PMID: 16618810 PMCID: PMC2063807 DOI: 10.1083/jcb.200509092] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The proteolytic activity of the cysteinyl aspartate–specific proteases, named caspases, mainly connotes their central role in apoptosis and inflammation. In this review we report on recent data on the role of caspases in the activation of nuclear factor κB (NF-κB), a transcription factor that fulfils a central role in innate and adaptive immunity, in cellular stress responses and in the induction of anti-apoptotic factors. Two different mechanisms by which caspases activate the NF-κB pathway are discussed.
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Affiliation(s)
- Mohamed Lamkanfi
- Unit of Molecular Signaling and Cell Death, Department for Molecular Biomedical Research, Flanders Interuniversity Institute for Biotechnology, VIB, Ghent University, B-9052 Ghent, Belgium
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Ward RD, Stone BM, Raetzman LT, Camper SA. Cell proliferation and vascularization in mouse models of pituitary hormone deficiency. Mol Endocrinol 2006; 20:1378-90. [PMID: 16556738 DOI: 10.1210/me.2005-0409] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Mutations in the transcription factors PIT1 (pituitary transcription factor 1) and PROP1 (prophet of Pit1) lead to pituitary hormone deficiency and hypopituitarism in mice and humans. To determine the basis for this, we performed histological analysis of Pit1- and Prop1-deficient dwarf mouse pituitaries throughout fetal and postnatal development. Pit1-deficient mice first exhibit pituitary hypoplasia after birth, primarily caused by reduced cell proliferation, although there is some apoptosis. To determine whether altered development of the vascular system contributes to hypopituitarism, we examined vascularization from embryonic d 14.5 and throughout development. No obvious differences in vascularization are evident in developing Pit1-deficient pituitaries. In contrast, the Prop1-deficient mouse pituitaries are poorly vascularized and dysmorphic, with a striking elevation in apoptosis. At postnatal d 11, apoptosis-independent caspase-3 activation occurs in thyrotropes and somatotropes of normal but not mutant pituitaries. This suggests that Prop1 and/or Pit1 may be necessary for caspase-3 expression. These studies provide further insight as to the mechanisms of Prop1 and Pit1 action in mice.
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Affiliation(s)
- Robert D Ward
- Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor 48109-0618, USA
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Oomman S, Strahlendorf H, Dertien J, Strahlendorf J. Bergmann glia utilize active caspase-3 for differentiation. Brain Res 2006; 1078:19-34. [PMID: 16700096 DOI: 10.1016/j.brainres.2006.01.041] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recently, functions associated with caspase have been modified from their well-established role in apoptosis. Although caspases are still regarded as mediators of apoptosis, some of the pro-apoptotic caspases, namely caspase-8, -14 and -3 also regulate differentiation in certain cell types, namely myelomonocytic cells, osteoblasts, skeletal muscle cells, keratinocytes, and T lymphocytes. In the central nervous system, non-apoptotic active caspase-3 expression has been located in proliferating and differentiating neuronal cells of the ventricular zone and external granular layer of the developing cerebellar cortex. We previously demonstrated that active caspase-3 expression was not limited to neuronal cells but also was located in the Bergmann glia of the postnatal cerebellum. In that study, active caspase-3 immunolabeling did not markedly colocalize with Ki67, a proliferation marker, but was present in differentiating Bergmann glia that expressed brain lipid binding protein (BLBP) and thus, by its localization, suggested a role in the differentiation of Bergmann glia. The current study addresses the function of caspase-3 in Bergmann glia development by utilizing a Bergmann glial culture preparation. Inhibition of caspase-3 activity by the peptide inhibitor, DMQD-FMK, increased the number of proliferating precursor glial cells and decreased the number of differentiating Bergmann glia, without significantly altering the non-glial active caspase-3 negative population. The transformation in the developmental state of Bergmann glia occurring after suppression of caspase-3 activity strongly suggests an involvement of this enzyme in promoting differentiation of Bergmann glia.
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Affiliation(s)
- Sowmini Oomman
- Department of Physiology, Room 5A163, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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Carson C, Saleh M, Fung FW, Nicholson DW, Roskams AJ. Axonal dynactin p150Glued transports caspase-8 to drive retrograde olfactory receptor neuron apoptosis. J Neurosci 2006; 25:6092-104. [PMID: 15987939 PMCID: PMC6725069 DOI: 10.1523/jneurosci.0707-05.2005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Olfactory receptor neurons (ORNs) undergo caspase-mediated retrograde apoptosis after target removal (bulbectomy), in which axonal caspase-9 and caspase-3 activation leads to terminal apoptosis in ORN soma of the olfactory epithelium. Here, we show that caspase-8 can act as an initiator of ORN apoptosis after bulbectomy and also after synaptic instability is induced by NMDA-mediated excitotoxic death of ORN target neurons in the olfactory bulb. Caspase-8 and caspase-3 are sequentially activated within ORN presynaptic terminals, and caspase-8 complexes with dynactin p150Glued, (a retrograde motor protein) and is transported retrogradely, preceding axonal caspase-3 activation and apoptosis of ORN cell bodies. Focal in vivo inhibition of initiator caspase activation or microtubule-dependent transport (with Taxol) at the lesioned axon terminus results in a significant reduction in retrograde axonal caspase-8 and caspase-3 activation and inhibition of retrograde ORN death. Caspase-8 activation and retrograde transport after NMDA lesion is similarly reduced in mice null for p75, the low-affinity nerve growth factor receptor. The retrograde apoptosis of ORNs thus involves a novel mechanism that used p75 in the local activation of caspase-8. Once caspase-8 is maximally activated in the presynaptic terminal, it is transported retrogradely by the motor complex dynactin/dynein, a process that can be inhibited focally to inhibit ORN apoptosis after acute axonal lesion. These data have revealed a novel mechanism of retrograde apoptosis, in which caspase-8 complexes directly with axonal dynactin p150Glued to reveal a differential vulnerability of subpopulations of ORNs to undergo apoptosis after axonal damage and the loss of olfactory bulb target neurons.
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Affiliation(s)
- Christine Carson
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada V5Z 4H4
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