401
|
Zhu X, Smith MA, Perry G, Wang Y, Ross AP, Zhao HW, Lamanna JC, Drew KL. MAPKs are differentially modulated in arctic ground squirrels during hibernation. J Neurosci Res 2005; 80:862-8. [PMID: 15884016 DOI: 10.1002/jnr.20526] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Hibernating animals are very tolerant of trauma to the central nervous system such that dramatic fluctuations in cerebral blood flow occur during hibernation and arousal without apparent damage. Indeed, it was demonstrated that Arctic ground squirrels (AGS) experience acute and severe systemic hypoxia along with the dramatic fluctuation in cerebral blood flow when the animals are aroused from hibernation. While initial hypotheses concerned protective mechanisms in the hibernating state, recent evidence of sustained elevation of HIF1alpha in euthermic AGS from our laboratory suggests that a preparatory program of protective gene expression is chronically expressed in euthermic AGS. In this study we evaluated potential neuroprotective adaptations by examining the alteration of intracellular MAPK pathways that may be modulated by hypoperfusion/reperfusion in AGS during hibernation and arousal. We found that ERK and JNK are activated in both euthermic and aroused AGS compared to the hibernating group which positively correlated with HIF1alpha levels. The activation of ERK and JNK associated with HIF1alpha may play an important role in mediating neuroprotective adaptations that is essential for successful hibernation. Interestingly, p38 is activated in euthermic AGS but not in aroused AGS, which shows strong correlation with iNOS induction. Therefore, the attenuation of p38 activation and iNOS induction in hibernating and aroused animals may contribute to the attenuation of inflammation that plays important neuroprotective roles during hibernation. Taken together, the differential modulation of the MAPK pathways may be critical for neuroprotection of AGS necessary for fluctuations in oxygen and nutrient delivery during hibernation.
Collapse
Affiliation(s)
- Xiongwei Zhu
- Institute of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA.
| | | | | | | | | | | | | | | |
Collapse
|
402
|
Esensten JH, Tsytsykova AV, Lopez-Rodriguez C, Ligeiro FA, Rao A, Goldfeld AE. NFAT5 binds to the TNF promoter distinctly from NFATp, c, 3 and 4, and activates TNF transcription during hypertonic stress alone. Nucleic Acids Res 2005; 33:3845-54. [PMID: 16027109 PMCID: PMC1175021 DOI: 10.1093/nar/gki701] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Tumor necrosis factor (TNF) is a pro-inflammatory cytokine that plays an important role in a variety of infectious and autoimmune disorders. Its transcription is regulated in a stimulus- and cell-type-specific manner via the recruitment of distinct DNA/activator complexes forming secondary structures or enhanceosomes. NFATp, a member of the nuclear factor of activated T cells (NFAT) family of transcription factors, plays a critical role in TNF gene regulation under a variety of conditions. In this study, we show that NFAT5, the most recently described NFAT family member, binds to the TNF promoter in a manner distinct from other NFAT proteins and is a key mediator in the activation of TNF gene transcription during hypertonic stress alone.
Collapse
Affiliation(s)
| | | | | | | | | | - Anne E. Goldfeld
- To whom correspondence should be addressed. Tel: +1 617 278 3351; Fax: +1 617 278 3454;
| |
Collapse
|
403
|
Jones NC, Tyner KJ, Nibarger L, Stanley HM, Cornelison DDW, Fedorov YV, Olwin BB. The p38alpha/beta MAPK functions as a molecular switch to activate the quiescent satellite cell. ACTA ACUST UNITED AC 2005; 169:105-16. [PMID: 15824134 PMCID: PMC2171902 DOI: 10.1083/jcb.200408066] [Citation(s) in RCA: 188] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Somatic stem cells cycle slowly or remain quiescent until required for tissue repair and maintenance. Upon muscle injury, stem cells that lie between the muscle fiber and basal lamina (satellite cells) are activated, proliferate, and eventually differentiate to repair the damaged muscle. Satellite cells in healthy muscle are quiescent, do not express MyoD family transcription factors or cell cycle regulatory genes and are insulated from the surrounding environment. Here, we report that the p38α/β family of mitogen-activated protein kinases (MAPKs) reversibly regulates the quiescent state of the skeletal muscle satellite cell. Inhibition of p38α/β MAPKs (a) promotes exit from the cell cycle, (b) prevents differentiation, and (c) insulates the cell from most external stimuli allowing the satellite cell to maintain a quiescent state. Activation of satellite cells and p38α/β MAPKs occurs concomitantly, providing further support that these MAPKs function as a molecular switch for satellite cell activation.
Collapse
Affiliation(s)
- Nathan C Jones
- Bayer Corporation, Research Triangle Park, NC 27709, USA
| | | | | | | | | | | | | |
Collapse
|
404
|
Chen HY, Zhu L, Zhan SM, Han ZW, Du W, Wang YJ, Cui RY, Wang CB. Polypeptide from Chlamys farreri inhibits murine thymocytes apoptosis and modulates UVB induced signaling pathway activation. Life Sci 2005; 77:768-79. [PMID: 15936351 DOI: 10.1016/j.lfs.2004.12.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2004] [Accepted: 12/22/2004] [Indexed: 11/24/2022]
Abstract
Polypeptide from Chlamys farreri (PCF) has been identified as a potent antioxidant and photoprotective agent. In this study, we investigated whether PCF could inhibit apoptosis of murine thymocytes induced by ultraviolet B (UVB) and modulate UVB induced the mitogen-activated protein kinases (MAPKs) cascade in vitro. Our results show that PCF inhibit UVB-induced apoptotic cell death in murine thymocytes. We also found that PCF potently stimulated the phosphorylation of ERKs, which is involved in the cell survival-signaling cascade. Furthermore, the specific inhibition of the ERKs pathways by PD98059 reduced the cytoprotective effect of PCF. On the other hand, the JNKs and p38 inhibitor SP600125 and SB203580 additively enhanced the cytoprotective effect of PCF. We concluded that the activation of JNKs and p38 kinase played an important role in UVB-induced apoptosis, and PCF likely exerted its cytoprotective effect in thymocytes through ERKs activation. These suggested that part of the antiapoptotic effect of PCF might be mediated by its ability to modulate the MAPKs cascade.
Collapse
Affiliation(s)
- Hai-Ying Chen
- Department of Pathophysiology, Medical College, Qingdao University, Qingdao, Shandong 266021, China
| | | | | | | | | | | | | | | |
Collapse
|
405
|
Madan P, Calder MD, Watson AJ. Mitogen-activated protein kinase (MAPK) blockade of bovine preimplantation embryogenesis requires inhibition of both p38 and extracellular signal-regulated kinase (ERK) pathways. Reproduction 2005; 130:41-51. [PMID: 15985630 DOI: 10.1530/rep.1.00554] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Blastocyst formation, as a critical period during development, is an effective indicator of embryonic health and reproductive efficiency. Out of a number of mechanisms underlying blastocyst formation, highly conserved mitogen-activated protein kinase (MAPK) signaling has emerged as a major mechanism involved in regulating murine preimplantation embryo development. The objective of our study was to ascertain the role of MAPK signaling in regulating bovine development to the blastocyst stage. Using reverse transcriptase PCR and immunohistochemical staining procedures we have demonstrated that mRNA transcripts and polypeptides encoding p38 MAPK pathway constituents are detectable in preimplantation bovine embryos from the one-cell to the blastocyst stage. Further, the effects on bovine embryo development following inhibition of p38 α/β and extracellular signal-regulated kinase (ERK) signaling by treatment with SB220025 and U0126, respectively, were investigated. Eight-cell bovine embryos (50 per group; three replicates) were placed into treatments consisting of synthetic oviductal fluid (SOF) medium: SOF + SB202474 (inactive analogue), SOF + SB220025, SOF + U0124 (inactive analogue), SOF + U0126, and SOF + SB220025 + U0126. Inhibition of p38 MAPK or ERK signaling individually did not affect development to the blastocyst stage. However, when both pathways were blocked simultaneously there was a significant reduction (P< 0.05) in blastocyst formation, cell number and immunofluorescence of phosphorylated downstream pathway constituents. We have determined that, in variance to what was observed during murine preimplantation development, bovine early embryos progress at normal frequencies to the blastocyst stage in the presence of p38 MAPK inhibitors.
Collapse
Affiliation(s)
- Pavneesh Madan
- Department of Physiology and Pharmacology, University of Western Ontario, Child Health Research Institute, 5th Floor Victoria Research Laboratories, 800 Commissioners Road East, London, Ontario, Canada, N6A 4G5
| | | | | |
Collapse
|
406
|
Waxman EA, Lynch DR. N-methyl-D-aspartate receptor subtype mediated bidirectional control of p38 mitogen-activated protein kinase. J Biol Chem 2005; 280:29322-33. [PMID: 15967799 DOI: 10.1074/jbc.m502080200] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
N-methyl-d-aspartate receptor (NMDAR) stimulation activates many downstream mechanisms involved in both cell survival and cell death. The manner in which the NMDAR regulates one of these pathways, the p38 mitogen-activated protein kinase (p38) pathway, is currently unknown. In the present study, we have defined a developmental-, concentration-, and time-dependent phosphorylation and subsequent dephosphorylation of p38. In cultured hippocampal neurons 7-8 days in vitro (DIV7-8), NMDAR stimulation leads to a concentration-dependent increase in p38 phosphorylation (phospho-p38). However, in more mature neurons (>DIV17) application of NMDA produces concentration-dependent effects, such that low concentrations result in sustained increases in phospho-p38 levels, and high concentrations dephosphorylate p38 within 5 min. Conantokin G, an antagonist of NR1/2A/2B and NR1/2B receptors, inhibits p38 phosphorylation, while NR1/2B-specific antagonists prevent the rapid dephosphorylation of p38 without affecting p38 activation. Furthermore, inhibition of calcineurin prevents the activation of p38, whereas inhibition of phosphoinositide 3-kinase (PI3K) prevents the rapid dephosphorylation of p38. Our results support the presence of subtype-dependent pathways regulating p38 activation and deactivation: one involves NR1/2A/2B receptors activating calcineurin and resulting in p38 phosphorylation, and the other utilizes NR1/2B receptors binding to and activating PI3K and leading to the dephosphorylation of p38 in a manner involving both NR1/2A/2B receptor activation and tyrosine phosphorylation of NR2B. The ability of NMDAR subtype-specific mechanisms to regulate p38 has implications for NMDAR-mediated synaptic plasticity, gene regulation, and excitotoxicity.
Collapse
Affiliation(s)
- Elisa A Waxman
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | | |
Collapse
|
407
|
Waxman EA, Lynch DR. N-methyl-D-aspartate receptor subtypes: multiple roles in excitotoxicity and neurological disease. Neuroscientist 2005; 11:37-49. [PMID: 15632277 DOI: 10.1177/1073858404269012] [Citation(s) in RCA: 255] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
N-methyl-D-aspartate (NMDA) receptors are the major mediator of excitotoxicity. Although physiological activation of the NMDA receptor is necessary for cell survival, overactivation is a signal for cell death. Several pathways are activated through NMDA receptor stimulation, most of which can contribute to excitotoxicity. These include events leading to mitochondrial dysfunction, activation of calcium-dependent enzymes, and activation of mitogen-activated protein kinase pathways. Understanding the role of these mechanisms is important in developing agents that block excitotoxicity without inhibiting functions necessary for survival. NMDA receptor subtypes may be responsible for mediating separate pathways, and subtype-specific inhibition has shown promising results in some neurological models. This review examines the roles of NMDA receptor subtypes in excitotoxicity and neurological disorders.
Collapse
Affiliation(s)
- Elisa A Waxman
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, USA
| | | |
Collapse
|
408
|
Gu M, Dhanalakshmi S, Mohan S, Singh RP, Agarwal R. Silibinin inhibits ultraviolet B radiation-induced mitogenic and survival signaling, and associated biological responses in SKH-1 mouse skin. Carcinogenesis 2005; 26:1404-13. [PMID: 15831527 DOI: 10.1093/carcin/bgi096] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ultraviolet B (UVB) radiation is a complete skin carcinogen causing DNA damage as a tumor-initiating event and activating signaling cascades that play a critical role in its tumor-promoting potential. Recently we reported that a naturally occurring flavonoid, silibinin, protects UVB-induced skin damages and prevents photocarcinogenesis. Here we examined silibinin efficacy on acute and chronic UVB-caused mitogen-activated protein kinases (MAPKs) and AKT activation and associated biological responses in SKH-1 hairless mouse skin. A single UVB exposure at 180 mJ/cm2 dose resulted in varying degrees of ERK1/2, JNK1/2, MAPK/p38 and AKT phosphorylation at various time-points in mouse skin; however, topical application of silibinin prior to or immediately after UVB exposure, or its dietary feeding strongly inhibited the activation of these molecules at all the time-points examined. Stronger effects of silibinin towards inhibition of UVB-caused phosphorylation of MAPKs and AKT were also observed in a chronic UVB (180 mJ/cm2/day for 5 days) exposure protocol. Immunohistochemical analysis of chronically exposed skin sections showed that silibinin treatment in all three protocols increases UVB-induced p53-positive cells and decreases UVB-caused cell proliferation, apoptotic and sunburn cells. These findings suggest that silibinin inhibits UVB-induced MAPK and AKT signaling and increases p53 in mouse skin, and that these effects of silibinin possibly lead to a decrease in UVB-caused proliferation and apoptosis, which might, in part, be responsible for its overall efficacy against photocarcinogenesis.
Collapse
Affiliation(s)
- Mallikarjuna Gu
- Department of Pharmaceutical Sciences, School of Pharmacy and University of Colorado Cancer Center, University of Colorado Health Sciences Center, Denver, CO 80262, USA
| | | | | | | | | |
Collapse
|
409
|
Prasmickaite L, Høgset A, Engesaeter B BØ, Bonsted A, Berg K. Light-directed gene delivery by photochemical internalisation. Expert Opin Biol Ther 2005; 4:1403-12. [PMID: 15335308 DOI: 10.1517/14712598.4.9.1403] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This article reviews a novel technology, named photochemical internalisation (PCI), for light-directed delivery of transgenes. Most gene therapy vectors are taken into the cell by endocytosis and, hence, are located in the endocytic vesicles. Although viral vectors have developed the means to escape from these vesicles, poor endosomal release is one of the major obstacles for non-viral vectors. PCI is a technology that allows liberation of the entrapped vectors carrying a gene in response to illumination. The method is based on chemical compounds (photosensitisers) that localise specifically in the membranes of endocytic vesicles and, following activation by light, induce the rupture of the vesicular membranes. The released transgenes can further be transferred to the nucleus, transcribed and translated. As gene liberation depends on light, enhancement of gene expression is achieved only at illuminated regions. PCI substantially improves gene transfer in vitro not only with non-viral gene vectors, but, surprisingly, also with adenoviruses and adeno-associated viruses. This article will review the background for the PCI technology and its role for gene delivery using both non-viral and viral vectors. Some aspects of the potential of PCI for site-specific gene delivery in therapeutic situations will also be discussed.
Collapse
Affiliation(s)
- Lina Prasmickaite
- Department of Radiation Biology, The Norwegian Radium Hospital, Montebello, N-0310 Oslo, Norway.
| | | | | | | | | |
Collapse
|
410
|
Kim YM, Reed W, Lenz AG, Jaspers I, Silbajoris R, Nick HS, Samet JM. Ultrafine carbon particles induce interleukin-8 gene transcription and p38 MAPK activation in normal human bronchial epithelial cells. Am J Physiol Lung Cell Mol Physiol 2005; 288:L432-41. [PMID: 15695543 DOI: 10.1152/ajplung.00285.2004] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Epidemiological studies suggest that ultrafine particles contribute to particulate matter-induced adverse health effects. Interleukin (IL)-8 is an important proinflammatory cytokine in the human lung that is induced in respiratory cells exposed to a variety of environmental insults, including ambient air ultrafine particles. In this study, we examined the effect of a model ultrafine particle on IL-8 expression and the cellular mechanisms responsible for this event. Here, we report that carbonaceous ultrafine particles consisting of synthetic elemental carbon particles (UfCP) markedly increase the expression of IL-8 mRNA and protein in normal human bronchial epithelial (NHBE) cells. IL-8 promoter activity was increased by UfCP exposure in NHBE cells, indicating UfCP-induced IL-8 expression is transcriptionally regulated. IL-8 expression in NHBE is known to be regulated by nuclear factor (NF)-κB activation. However, UfCP did not induce inhibitory factor κBα degradation, NF-κB-DNA binding, or NF-κB-dependent promoter activity in NHBE cells, indicating that UfCP induces IL-8 expression through a mechanism that is independent of NF-κB activation. Additionally, we observed that UfCP exposure induces the phosphorylation and activation of p38 mitogen-activated protein kinase (MAPK) in a biphasic manner and that the inhibition of p38 MAPK activity can block IL-8 mRNA expression induced by UfCP in NHBE cells. These results demonstrate that UfCP-induced expression of IL-8 involves a transcriptional mechanism and activation of p38 MAPK in NHBE cells.
Collapse
Affiliation(s)
- Yu-Mee Kim
- Department of Environmental Sciences and Engineering, School of Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | | | | | | | | | | | | |
Collapse
|
411
|
MacDonald JA, Storey KB. Mitogen-activated protein kinases and selected downstream targets display organ-specific responses in the hibernating ground squirrel. Int J Biochem Cell Biol 2005; 37:679-91. [PMID: 15618024 DOI: 10.1016/j.biocel.2004.05.023] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2003] [Revised: 05/01/2004] [Accepted: 05/17/2004] [Indexed: 11/24/2022]
Abstract
The responses of mitogen-activated protein kinase (MAPK) family members, including the extracellular signal-regulated kinases (ERKs), the c-jun NH2-terminal kinases (JNKs) and p38MAPK, during mammalian hibernation were analyzed in five organs of Richardson's ground squirrels, Spermophilus richardsonii. Each kinase subfamily responded differently in torpor and each showed organ-specific patterns of response. ERK1/2 activities increased significantly in muscle and brain during hibernation but decreased in kidney and liver. JNK activity rose in four organs (except brain) during hibernation whereas active, phosphorylated p38MAPK increased only in muscle and heart. Activities of ERK-activated kinases also responded to hibernation: MAPKAPK-1 rose in muscle and brain, MAPKAPK-2 decreased in liver and kidney but rose in the other three organs, and p70S6K kinase activity decreased kidney and heart. Transcription factors, c-Jun and CREB, also showed organ-specific responses during torpor. The data suggest key roles for MAPKs in the regulation of the known organ-specific changes in gene expression and protein phosphorylation that define the hibernation phenotype.
Collapse
Affiliation(s)
- Justin A MacDonald
- Department of Biochemistry and Molecular Biology, University of Calgary, 3330 Hospital Drive N.W., Calgary, AB, Canada T2N 4N1
| | | |
Collapse
|
412
|
Haddad JJ. Hypoxia and the regulation of mitogen-activated protein kinases: gene transcription and the assessment of potential pharmacologic therapeutic interventions. Int Immunopharmacol 2005; 4:1249-85. [PMID: 15313426 DOI: 10.1016/j.intimp.2004.06.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2004] [Revised: 06/09/2004] [Accepted: 06/15/2004] [Indexed: 12/20/2022]
Abstract
Oxygen is an environmental/developmental signal that regulates cellular energetics, growth, and differentiation processes. Despite its central role in nearly all higher life processes, the molecular mechanisms for sensing oxygen levels and the pathways involved in transducing this information are still being elucidated. Altering gene expression is the most fundamental and effective way for a cell to respond to extracellular signals and/or changes in its microenvironment. During development, the expression of specific sets of genes is regulated spatially (by position/morphogenetic gradients) and temporally, presumably via the sensing of molecular oxygen available within the microenvironment. Regulation of signaling responses is governed by transcription factors that bind to control regions (consensus sequences) of target genes and alter their expression in response to specific signals. Complex signal transduction during hypoxia (deficiency of oxygen in inspired gases or in arterial blood and/or in tissues) involves the coupling of ligand-receptor interactions to many intracellular events. These events basically include phosphorylations by tyrosine kinases and/or serine/threonine kinases, such as those of mitogen-activated protein kinases (MAPKs), a superfamily of kinases responsive to stress nonhomeostatic conditions. Protein phosphorylations imposed during hypoxia change enzyme activities and protein conformations, and the eventual outcome is rather complex, comprising of an alteration in cellular activity and changes in the programming of genes expressed within the responding cells. These molecular changes serve as signals that are crucial for cell survival under contingent conditions imposed during hypoxia. This review correlates current concepts of hypoxic sensing pathways with hypoxia-related phosphorylation mechanisms mediated by MAPKs via the genetic and pharmacologic regulation/manipulation of specific transcription factors and related cofactors.
Collapse
Affiliation(s)
- John J Haddad
- Severinghaus-Radiometer Research Laboratories, University of California, San Francisco, CA, USA.
| |
Collapse
|
413
|
Rebaï O, Le Petit-Thevenin J, Bruneau N, Lombardo D, Vérine A. In Vitro Angiogenic Effects of Pancreatic Bile Salt-Dependent Lipase. Arterioscler Thromb Vasc Biol 2005; 25:359-64. [PMID: 15569825 DOI: 10.1161/01.atv.0000151618.49109.bd] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE Bile salt-dependent lipase (BSDL), a lipolytic enzyme secreted in the duodenum by pancreatic acinar cells, has been detected in the serum of all patients and in atheromatous plaque, suggesting its potential implication in vascular pathophysiology. METHODS AND RESULTS In vitro pancreatic BSDL evokes human umbilical vein endothelial cell (HUVEC) proliferation and chemotactic migration. BSDL at mitogen concentration is capable to heal wounded HUVEC monolayer and to promote capillary network formation. HUVEC proliferation depends on the displacement of basic fibroblast growth factor and vascular endothelial growth factor from the extracellular matrix and the activation of extracellular signal-regulated kinases (ERK1/2), p38 mitogen-activated protein kinase, and focal adhesion kinase signaling pathways. CONCLUSIONS For the first time to our knowledge, it is suggested that circulating BSDL could be involved in pathophysiological angiogenesis. We delineate the in vitro effects of pancreatic BSDL on endothelial cells, and we show that BSDL promotes proliferation, migration, capillary network formation, and wound-healing of HUVECs via the displacement of bFGF and VEGF from the ECM, suggesting that BSDL could be involved in angiogenesis.
Collapse
Affiliation(s)
- Ouafa Rebaï
- INSERM U-559 and IPHM, Marseille-cedex, France
| | | | | | | | | |
Collapse
|
414
|
Geigl JB, Langer S, Barwisch S, Pfleghaar K, Lederer G, Speicher MR. Analysis of gene expression patterns and chromosomal changes associated with aging. Cancer Res 2005; 64:8550-7. [PMID: 15574761 DOI: 10.1158/0008-5472.can-04-2151] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Age is the largest single risk factor for the development of cancer in mammals. Age-associated chromosomal changes, such as aneuploidy and telomere erosion, may be vitally involved in the initial steps of tumorigenesis. However, changes in gene expression specific for increased aneuploidy with age have not yet been characterized. Here, we address these questions by using a panel of fibroblast cell lines and lymphocyte cultures from young and old age groups. Oligonucleotide microarrays were used to characterize the expression of 14,500 genes. We measured telomere length and analyzed chromosome copy number changes and structural rearrangements by multicolor interphase fluorescence in situ hybridization and 7-fluorochrome multiplex fluorescence in situ hybridization, and we tried to show a relationship between gene expression patterns and chromosomal changes. These analyses revealed a number of genes involved in both the cell cycle and proliferation that are differently expressed in aged cells. More importantly, our data show an association between age-related aneuploidy and the gene expression level of genes involved in centromere and kinetochore function and in the microtubule and spindle assembly apparatus. To verify that some of these genes may also be involved in tumorigenesis, we compared the expression of these genes in chromosomally stable microsatellite instability and chromosomally unstable chromosomal instability colorectal tumor cell lines. Three genes (Notch2, H2AFY2, and CDC5L) showed similar expression differences between microsatellite instability and chromosomal instability cell lines as observed between the young and old cell cultures suggesting that they may play a role in tumorigenesis.
Collapse
Affiliation(s)
- Jochen B Geigl
- Institute of Human Genetics, Technical University, Munich, Germany
| | | | | | | | | | | |
Collapse
|
415
|
Canesi L, Betti M, Lorusso LC, Ciacci C, Gallo G. 'In vivo' effects of Bisphenol A in Mytilus hemocytes: modulation of kinase-mediated signalling pathways. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2005; 71:73-84. [PMID: 15642633 DOI: 10.1016/j.aquatox.2004.10.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2004] [Revised: 10/13/2004] [Accepted: 10/14/2004] [Indexed: 05/24/2023]
Abstract
Endocrine disrupting chemicals (EDCs) include a variety of natural and synthetic estrogens, as well as estrogen-mimicking chemicals. We have previously shown that in the hemocytes of the mussel Mytilus galloprovincialis Lam. both natural and environmental estrogens in vitro can rapidly affect the phosphorylation state of components of tyrosine kinase-mediated cell signalling, in particular of mitogen activated protein kinases (MAPKs) and signal transducers and activators of transcription (STAT), that are involved in mediating the hemocyte immune response. These effects were consistent with the hypothesis that 'alternative' modes of estrogen action involving kinase-mediated pathways similar to those described in mammalian systems are also present in invertebrate cells. This possibility was investigated in vivo with Bisphenol A (BPA): mussels were injected with BPA and hemocytes sampled at 6, 12, and 24 h post-injection. The results show that BPA (25 nM nominal concentration in the hemolymph) lead to a significant lysosomal membrane destabilisation at all times post-injection, indicating BPA-induced stress conditions in the hemocytes, whereas lower concentrations were ineffective. BPA induced significant changes in the phosphorylation state of MAPK and STAT members, as evaluated by SDS-PAGE and WB of hemocyte protein extracts with specific antibodies, although to a different degree at different exposure times. In particular, BPA induced a dramatic decrease in phosphorylation of the stress-activated p38 MAPK, whose activation is crucial in mediating the bactericidal activity. Moreover, BPA decreased the phosphorylation of a CREB-like transcription factor (cAMP-responsive element binding protein). The results demonstrate that BPA can affect kinase-mediated cell signalling in mussel hemocytes also in vivo, and suggest that EDCs may affect gene expression in mussel cells through modulation of the activity of transcription factors secondary to cytosolic kinase cascades. Overall, these data address the importance of investigating full range responses to EDCs in ecologically relevant marine invertebrate species.
Collapse
Affiliation(s)
- Laura Canesi
- Istituto di Scienze Fisiologiche, Università di Urbino Carlo Bo, Loc. Crocicchia, 61029 Urbino PU, Italy.
| | | | | | | | | |
Collapse
|
416
|
|
417
|
Michlig S, Mercier A, Doucet A, Schild L, Horisberger JD, Rossier BC, Firsov D. ERK1/2 Controls Na,K-ATPase Activity and Transepithelial Sodium Transport in the Principal Cell of the Cortical Collecting Duct of the Mouse Kidney. J Biol Chem 2004; 279:51002-12. [PMID: 15456767 DOI: 10.1074/jbc.m405674200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The collecting duct of normal kidney exhibits significant activity of the MEK1/2-ERK1/2 pathway as shown in vivo by immunostaining of phosphorylated active ERK1/2 (pERK1/2). The MEK1/2-ERK1/2 pathway controls many different ion transports both in proximal and distal nephron, raising the question of whether this pathway is involved in the basal and/or hormone-dependent transepithelial sodium reabsorption in the principal cell of the cortical collecting duct (CCD), a process mediated by the apical epithelial sodium channel and the basolateral sodium pump (Na,K-ATPase). To answer this question we used ex vivo microdissected CCDs from normal mouse kidney or in vitro cultured mpkCCDcl4 principal cells. Significant basal levels of pERK1/2 were observed ex vivo and in vitro. Aldosterone and vasopressin, known to up-regulate sodium reabsorption in CCDs, did not change ERK1/2 activity either ex vivo or in vitro. Basal and aldosterone- or vasopressin-stimulated sodium transport was down-regulated by the MEK1/2 inhibitor PD98059, in parallel with a decrease in pERK1/2 in vitro. The activity of Na,K-ATPase but not that of epithelial sodium channel was inhibited by MEK1/2 inhibitors in both unstimulated and aldosterone- or vasopressin-stimulated CCDs in vitro. Cell surface biotinylation showed that intrinsic activity rather than cell surface expression of Na,K-ATPase was controlled by pERK1/2. PD98059 also significantly inhibited the activity of Na,K-ATPase ex vivo. Our data demonstrate that the ERK1/2 pathway controls Na,K-ATPase activity and transepithelial sodium transport in the principal cell and indicate that basal constitutive activity of the ERK1/2 pathway is a critical component of this control.
Collapse
Affiliation(s)
- Stéphanie Michlig
- Département de Pharmacologie et de Toxicologie, Université de Lausanne, CH-1005 Lausanne, Switzerland
| | | | | | | | | | | | | |
Collapse
|
418
|
|
419
|
Takahashi Y, Lavigne JA, Hursting SD, Chandramouli GVR, Perkins SN, Barrett JC, Wang TTY. Using DNA microarray analyses to elucidate the effects of genistein in androgen-responsive prostate cancer cells: identification of novel targets. Mol Carcinog 2004; 41:108-119. [PMID: 15378649 DOI: 10.1002/mc.20045] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Many studies have correlated the consumption of soy-rich diets with a decreased risk of developing hormone-dependent cancers, including prostate cancer. Genistein is a candidate prostate cancer preventive phytochemical found at high levels in soybean and soy foods. To better understand the molecular mechanisms underlying the beneficial effects of genistein on prostate cancer prevention, we used a DNA microarray approach to examine the effects of genistein at concentrations in the physiologic range on global gene expression patterns in androgen-responsive cancer cells. Microarray analyses were performed on androgen-responsive LNCaP human prostate cancer cells exposed to 0, 1, 5, or 25 microM genistein. We found a concentration-dependent modulation of multiple cellular pathways that are important in prostate carcinogenesis. Interestingly, the androgen receptor (AR)-mediated pathways, in particular, appeared to be modulated by genistein at the lowest concentrations. Based on these results, we propose that the regulation of AR-mediated pathways is potentially the most relevant chemopreventive mechanism for genistein administered at physiologic levels.
Collapse
Affiliation(s)
- Yoko Takahashi
- Phytonutrients Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service/ USDA, Beltsville, MD 20705, USA
| | | | | | | | | | | | | |
Collapse
|
420
|
Chik CL, Mackova M, Price D, Ho AK. Adrenergic regulation and diurnal rhythm of p38 mitogen-activated protein kinase phosphorylation in the rat pineal gland. Endocrinology 2004; 145:5194-201. [PMID: 15297444 DOI: 10.1210/en.2004-0864] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In this study, we investigated adrenergic and photoneural regulation of p38MAPK phosphorylation in the rat pineal gland. Norepinephrine (NE), the endogenous neurotransmitter, dose-dependently increased the levels of phosphorylated MAPK kinase 3/6 (MKK3/6) and p38MAPK in rat pinealocytes. Time-course studies showed a gradual increase in MKK3/6 and p38MAPK phosphorylation that peaked between 1 and 2 h and persisted for 4 h post NE stimulation. In cells treated with NE for 2 and 4 h, the inclusion of prazosin or propranolol reduced NE-induced MKK3/6 and p38MAPK phosphorylation, indicating involvement of both alpha- and beta-adrenergic receptors for the sustained response. Whereas treatment with dibutyryl cAMP or ionomycin mimicked the NE-induced MKK3/6 and p38MAPK phosphorylation, neither dibutyryl cGMP nor 4beta-phorbol 12-myristate 13-acetate had an effect. The NE-induced increase in MKK3/6 and p38MAPK phosphorylation was blocked by KT5720 (a protein kinase A inhibitor) and KN93 (a Ca(2+)/calmodulin-dependent kinase inhibitor), but not by KT5823 (a protein kinase G inhibitor) or calphostin C (a protein kinase C inhibitor). In animals housed under a lighting regimen with 12 h of light, MKK3/6 and p38MAPK phosphorylation increased in the rat pineal gland at zeitgeber time 18. The nocturnal increase in p38MAPK phosphorylation was blocked by exposing the animal to constant light and reduced by treatment with propranolol, a beta-adrenergic blocker. Together, our results indicate that activation of p38MAPK is under photoneural control in the rat pineal gland and that protein kinase A and intracellular Ca(2+) signaling pathways are involved in NE regulation of p38MAPK.
Collapse
Affiliation(s)
- C L Chik
- Department of Physiology, 7-26 Medical Sciences Building, Edmonton, Alberta, Canada
| | | | | | | |
Collapse
|
421
|
Storey KB. Adventures in oxygen metabolism. Comp Biochem Physiol B Biochem Mol Biol 2004; 139:359-69. [PMID: 15544961 DOI: 10.1016/j.cbpc.2004.02.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2003] [Revised: 02/02/2004] [Accepted: 02/03/2004] [Indexed: 10/26/2022]
Abstract
Peter W. Hochachka led a grand life of science adventure and left as his legacy a whole new field--biochemical adaptation. Oxygen was at the core of Peter's career and his laboratory made major contributions to our understanding of how animals deal with variation in oxygen availability in many forms. He analyzed the molecular mechanisms that support facultative anaerobiosis, studied muscle exercise metabolism for high speed flight, swimming and running, investigated mammalian diving on many trips to the Antarctic to study Weddell seals, and probed the metabolic and genetic adaptations that provide optimal hypoxia tolerance for humans residing at high altitudes. His work illuminated both biochemical and physiological mechanisms that are used to optimize aerobic metabolism, to compensate for hypoxic insults, and to conserve energy by strong metabolic rate depression under anoxia. His articles, books and lectures galvanized the field with leading-edge insights and theories and he consistently challenged comparative biochemists to use their unique model systems to explore the range and breadth of animal strategies of biochemical adaptation. Lessons drawn from my training in Peter's laboratory have led me on continuing explorations of adaptations in enzyme function, signal transduction, gene expression, and antioxidant defenses ranging over systems of anoxia tolerance, freezing survival, estivation, and mammalian hibernation.
Collapse
Affiliation(s)
- Kenneth B Storey
- Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, ON, Canada K1S 5B6.
| |
Collapse
|
422
|
Bartrons M, Ortega E, Obach M, Calvo MN, Navarro-Sabaté A, Bartrons R. Activation of AMP-dependent protein kinase by hypoxia and hypothermia in the liver of frog Rana perezi. Cryobiology 2004; 49:190-4. [PMID: 15351690 DOI: 10.1016/j.cryobiol.2004.06.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2004] [Accepted: 06/28/2004] [Indexed: 11/16/2022]
Abstract
We have investigated different signaling molecules that could be activated by temperature acclimation and hypoxia, using an experimental approach consisting in submerging frogs in a water-filled box maintained at 2-4 degrees C at ambient oxygen levels or supplied with 98% N2:2% CO2 for normoxia or hypoxia conditions, respectively. The results obtained showed no significant changes in the expression of heat shock protein 70. The phosphorylation state of AMP-dependent activated protein kinase, the down-stream component of a protein kinase cascade that acts as an intracellular energy sensor, was significantly increased in both experimental conditions, showing higher values in the absence of oxygen. Similarly, the phosphorylation state of one of its known substrates, elongation factor 2, was also increased, consistent with the arrest of protein synthesis. These results point out an important role of this kinase, adjusting the rates of ATP-consuming and ATP-generating pathways, in the survival strategies to hypoxia and hypothermia.
Collapse
Affiliation(s)
- Mireia Bartrons
- Unitat de Bioquímica i Biologia Molecular, Departament de Ciències Fisiològiques II, Campus de Bellvitge, Universitat de Barcelona, Feixa Llarga s/n, E-08907 L'Hospitalet, Spain
| | | | | | | | | | | |
Collapse
|
423
|
Marden JH, Cobb JR. Territorial and mating success of dragonflies that vary in muscle power output and presence of gregarine gut parasites. Anim Behav 2004. [DOI: 10.1016/j.anbehav.2003.09.019] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
424
|
Abstract
Evidence has accumulated that inositol pyrophosphates (diphosphoinositol pentakisphosphate (PP-InsP5) and bisdiphosphoinositol tetrakisphosphate ([PP]2-InsP4)) are intracellular signals that regulate many cellular processes including endocytosis, vesicle trafficking, apoptosis, and DNA repair. Yet, in contrast to the situation with all other second messengers, no one studying multicellular organisms has previously described a stimulus that acutely and specifically elevates cellular levels of PP-InsP5 or [PP]2-InsP4. We now show up to 25-fold elevations in [PP]2-InsP4 levels in animal cells. Importantly, this does not involve classical agonists. Instead, we show that this [PP]2-InsP4 response is a novel consequence of the activation of ERK1/2 and p38MAPalpha/beta kinases by hyperosmotic stress. JNK did not participate in regulating [PP]2-InsP4 levels. Identification of [PP]2-InsP4 as a sensor of hyperosmotic stress opens up a new area of research for studies into the cellular activities of higher inositol phosphates.
Collapse
Affiliation(s)
- Xavier Pesesse
- Inositide Signaling Group, NIEHS, National Institutes of Health, Department of Health and Social Services, Research Triangle Park, North Carolina 27709, USA
| | | | | | | |
Collapse
|
425
|
Li W, Hou L, Hua Z, Wang X. Interleukin-1beta induces beta-calcitonin gene-related peptide secretion in human type II alveolar epithelial cells. FASEB J 2004; 18:1603-5. [PMID: 15319367 DOI: 10.1096/fj.04-1737fje] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Calcitonin gene-related peptide (CGRP) is a 37-amino acid neuropeptide mainly present in sensory nerve fibers, which is present in almost all organs, but it is also found in cultured rat type II alveolar epithelial cells (AEII). Our data have previously shown that CGRP may play an important role in inflammation as an immunomodulator. Proinflammatory factor IL-1beta induces CGRP release from neuron-derived sources. However, whether IL-1beta can induce CGRP secretion from a nonneural source, AEII cells, is not known. In the present study, we demonstrated that human AEII A549 cells expressed beta-CGRP, and IL-1beta (0.001-50 ng/ml) directly increased CGRP secretion from these cells in a time- and concentration-dependent manner. The mRNA level of beta-CGRP was also elevated by IL-1beta (1 ng/ml). In addition, we found that IL-1beta-induced CGRP production was mediated through the PKC-p38 mitogen-activated protein (MAP) kinase-NF-kappaB signaling pathway. Furthermore, IL-1beta-induced chemokines MCP-1 and IL-8 were partially inhibited by exogenous hCGRP (0.1-10 nM) and potentiated by hCGRP8-37 (0.1-10 nM), a CGRP1-receptor antagonist. In addition, the CGRP-inhibited chemokine effect was partially reduced by Rp-cAMP, a cAMP-PK inhibitor. These results suggest that AEII-derived CGRP may act in an autocrine/paracrine mode and play an important inhibitory role in the local area in lung inflammatory diseases.
Collapse
Affiliation(s)
- Wenjing Li
- Institute of Vascular Medicine, Peking University Third Hospital, Beijing 100083, P. R. of China
| | | | | | | |
Collapse
|
426
|
Togo T. Long-term potentiation of wound-induced exocytosis and plasma membrane repair is dependent on cAMP-response element-mediated transcription via a protein kinase C- and p38 MAPK-dependent pathway. J Biol Chem 2004; 279:44996-5003. [PMID: 15317814 DOI: 10.1074/jbc.m406327200] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ca(2+)-regulated exocytosis is required for rapid resealing of disrupted plasma membranes. It has been previously demonstrated that repeated membrane disruptions reseal more quickly than the initial wound and that this facilitated response requires the transcription factor cAMP-response element-binding protein (CREB). This study examines the signaling pathway between membrane disruption and CREB-dependent gene expression in 3T3 fibroblasts. A reporter gene assay using pCRE-d2EGFP revealed that membrane disruption induced CRE-mediated transcription. Immunofluorescence observations suggested that membrane disruption activated CREB, p38 mitogen-activated protein kinase (p38 MAPK), and MAPK kinase3/6, the kinase responsible for activation of p38 MAPK. CREB phosphorylation upon membrane disruption was inhibited by a specific p38 MAPK inhibitor, SB203580. Both CRE-mediated transcription and long-term potentiation of membrane resealing and wound-induced exocytosis were suppressed when cells were wounded in the presence of either SB203580 or Go-6976, a specific protein kinase C (PKC) inhibitor. Furthermore, activation of MAPK kinase3/6 was impaired by PKC inhibition during membrane disruption. These results suggest that PKC mediates the stimulation of CREB-dependent gene expression through a p38 MAPK pathway upon membrane disruption.
Collapse
Affiliation(s)
- Tatsuru Togo
- Misaki Marine Biological Station, The University of Tokyo, Misaki, Miura, Kanagawa 238-0225, Japan.
| |
Collapse
|
427
|
Mistry AC, Kato A, Tran YH, Honda S, Tsukada T, Takei Y, Hirose S. FHL5, a novel actin-binding protein, is highly expressed in eel gill pillar cells and responds to wall tension. Am J Physiol Regul Integr Comp Physiol 2004; 287:R1141-54. [PMID: 15284080 DOI: 10.1152/ajpregu.00108.2004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Supporting evidence for the contractile nature of fish branchial pillar cells was provided by demonstrating the presence of actin fibers and a novel four-and-a-half LIM (FHL) protein in which expression is specific for contractile tissues and sensitive to the tension applied to the pillar cell. When eel gill sections were stained with rhodamine-phalloidin, a selective fluorescent probe for fibrous actin, a strong bundle-like staining was observed around collagen columns in pillar cells, suggesting the presence of abundant actin fibers. A cDNA clone encoding a novel member of the actin-binding FHL family, FHL5, was isolated from a subtracted cDNA library of eel gill. Northern analysis revealed that FHL5 mRNA is highly expressed only in gills, heart, and skeletal muscle. In gills, FHL5 was found to be confined to pillar cells by immunohistochemistry. Confocal fluorescence microscopy showed that FHL5 is present in both cytosol and nucleus; within the cytosol, a large portion of FHL5 is colocalized with the phalloidin-positive actin bundles. Furthermore, transfection of myogenic C2C12 cells with FHL5 cDNA demonstrated, in addition to its interaction with actin stress fibers, a nuclear shuttling activity of FHL5. The mRNA and protein levels were found to be elevated on 1) transfer of eels from seawater to freshwater, 2) volume expansion by infusion of isotonic dextran-saline, and 3) constriction of gill vasculature by bolus injection of endothelin-1. These results suggest contractile nature of pillar cells and a role of FHL5 in maintaining the integrity and regulating the dynamics of pillar cells.
Collapse
MESH Headings
- Actins/metabolism
- Actins/physiology
- Amino Acid Sequence
- Animals
- Base Sequence
- Blotting, Western
- Cell Nucleus/physiology
- Cells, Cultured
- Cloning, Molecular
- DNA, Complementary/biosynthesis
- DNA, Complementary/genetics
- Eels/physiology
- Gene Expression Regulation/physiology
- Gills/cytology
- Gills/physiology
- Immunohistochemistry
- Injections, Intra-Arterial
- Microcirculation/physiology
- Microscopy, Confocal
- Microscopy, Fluorescence
- Molecular Sequence Data
- Muscle Contraction/physiology
- Muscle Fibers, Skeletal/physiology
- Muscle Proteins/metabolism
- Muscle Proteins/physiology
- Muscle, Smooth, Vascular/physiology
- Myosins/physiology
- Nucleic Acid Amplification Techniques
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
Collapse
Affiliation(s)
- Abinash Chandra Mistry
- Department of Biological Sciences, Tokyo Institute of Technology, 4259-B-19 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
| | | | | | | | | | | | | |
Collapse
|
428
|
Yamamoto TG, Chikashige Y, Ozoe F, Kawamukai M, Hiraoka Y. Activation of the pheromone-responsive MAP kinase drives haploid cells to undergo ectopic meiosis with normal telomere clustering and sister chromatid segregation in fission yeast. J Cell Sci 2004; 117:3875-86. [PMID: 15265989 DOI: 10.1242/jcs.01248] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Meiosis is a process of importance for sexually reproducing eukaryotic organisms. In the fission yeast Schizosaccharomyces pombe, meiosis normally proceeds in a diploid zygote which is produced by conjugation of haploid cells of opposite mating types. We demonstrate that activation of the pheromone-responsive MAPK, Spk1, by the ectopic expression of a constitutively active form of Byr1 (MAPKK for Spk1) induced the cells to undergo meiosis while in the haploid state. Moreover, the induction of meiosis required Mei2 (a key positive regulator of meiosis), but did not require Mei3; Mei3 is normally required to inactivate the Pat1 kinase (a negative regulator of Mei2) thereby allowing Mei2 to drive meiosis. Therefore, expression of a constitutively active form of Byr1 activates Mei2 without the need of Mei3. In cells induced to undergo meiosis by activating the Spk1 MAPK signaling pathway, telomeres clustered at the spindle pole body (SPB) and centromeres detached normally from the SPB during meiotic prophase, and the cells showed the correct segregation of sister chromatids during meiotic divisions. In contrast, in meiosis induced by inactivation of Pat1, sister chromatids segregate precociously during the first meiotic division. Thus, these results suggest that activation of Spk1 drives meiosis in S. pombe.
Collapse
Affiliation(s)
- Takaharu G Yamamoto
- Cell Biology Group and CREST Research Project, Kansai Advanced Research Center, National Institute of Information and Communication Technology, 588-2 Iwaoka-cho, Iwaoka, Nishi-ku, Kobe 651-2492, Japan
| | | | | | | | | |
Collapse
|
429
|
Armesilla AL, Williams JC, Buch MH, Pickard A, Emerson M, Cartwright EJ, Oceandy D, Vos MD, Gillies S, Clark GJ, Neyses L. Novel functional interaction between the plasma membrane Ca2+ pump 4b and the proapoptotic tumor suppressor Ras-associated factor 1 (RASSF1). J Biol Chem 2004; 279:31318-28. [PMID: 15145946 DOI: 10.1074/jbc.m307557200] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Plasma membrane calmodulin-dependent calcium ATPases (PMCAs) are enzymatic systems implicated in the extrusion of calcium from the cell. We and others have previously identified molecular interactions between the cytoplasmic COOH-terminal end of PMCA and PDZ domain-containing proteins. These interactions suggested a new role for PMCA as a modulator of signal transduction pathways. The existence of other intracellular regions in the PMCA molecule prompted us to investigate the possible participation of other domains in interactions with different partner proteins. A two-hybrid screen of a human fetal heart cDNA library, using the region 652-840 of human PMCA4b (located in the catalytic, second intracellular loop) as bait, revealed a novel interaction between PMCA4b and the tumor suppressor RASSF1, a Ras effector protein involved in H-Ras-mediated apoptosis. Immunofluorescence co-localization, immunoprecipitation, and glutathione S-transferase pull-down experiments performed in mammalian cells provided further confirmation of the physical interaction between the two proteins. The interaction domain has been narrowed down to region 74-123 of RASSF1C (144-193 in RASSF1A) and 652-748 of human PMCA4b. The functionality of this interaction was demonstrated by the inhibition of the epidermal growth factor-dependent activation of the Erk pathway when PMCA4b and RASSF1 were co-expressed. This inhibition was abolished by blocking PMCA/RASSSF1 association with an excess of a green fluorescent protein fusion protein containing the region 50-123 of RASSF1C. This work describes a novel protein-protein interaction involving a domain of PMCA other than the COOH terminus. It suggests a function for PMCA4b as an organizer of macromolecular protein complexes, where PMCA4b could recruit diverse proteins through interaction with different domains. Furthermore, the functional association with RASSF1 indicates a role for PMCA4b in the modulation of Ras-mediated signaling.
Collapse
Affiliation(s)
- Angel L Armesilla
- Division of Cardiology, University of Manchester, Manchester M13 9PT, United Kingdom
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
430
|
Huang Z, Tunnacliffe A. Response of human cells to desiccation: comparison with hyperosmotic stress response. J Physiol 2004; 558:181-91. [PMID: 15146043 PMCID: PMC1664923 DOI: 10.1113/jphysiol.2004.065540] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Increasing interest in anhydrobiosis ('life without water') has prompted the use of mammalian cells as a model in which candidate adaptations suspected of conferring desiccation tolerance can be tested. Despite this, there is no information on whether mammalian cells are able to sense and respond to desiccation. We have therefore examined the effect of desiccation on stress signalling pathways and on genes which are proposed to be expressed in response to water loss through osmotic stress. Depending on the severity of the drying regime, human cells survived for at least 24 h. Both SAPK/JNK and p38 mitogen-activated protein kinases (MAPKs) were activated within 30 min by desiccation as well as by all osmotica tested, and therefore MAPK pathways probably play an important role in both responses. Gene induction profiles differed under the two stress conditions, however: quantitative polymerase chain reaction (PCR) experiments showed that AR, BGT-1 and SMIT, which encode proteins governing organic osmolyte accumulation, were induced by hypersalinity but not by desiccation. This was surprising, since these genes have been proposed to be regulated by ionic strength and cell volume, both of which should be significantly affected in drying cells. Further investigation demonstrated that AR, BGT-1 and SMIT expression was dependent on the nature of the osmolyte. This suggests that their regulation involves factors other than intracellular ionic strength and cell volume changes, consistent with the lack of induction by desiccation. Our results show for the first time that human cells react rapidly to desiccation by MAPK activation, and that the response partially overlaps with that to hyperosmotic stress.
Collapse
Affiliation(s)
- Zebo Huang
- Institute of Biotechnology University of Cambridge, Tennis Court Road, Cambridge CB2 1QT, UK
| | | |
Collapse
|
431
|
Chen Y, Shukla A, Namiki S, Insel PA, Junger WG. A putative osmoreceptor system that controls neutrophil function through the release of ATP, its conversion to adenosine, and activation of A2 adenosine and P2 receptors. J Leukoc Biol 2004; 76:245-53. [PMID: 15107462 DOI: 10.1189/jlb.0204066] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We have previously shown that hypertonic stress (HS) can suppress chemoattractant-induced neutrophil responses via cyclic adenosine monophosphate and enhance these responses through p38 mitogen-activated protein kinase (MAPK) activation. The underlying mechanisms are unknown. Here, we report that HS dose-dependently releases adenosine 5'-triphosphate (ATP) from neutrophils and that extracellular ATP is rapidly converted to adenosine or activates p38 MAPK and enhances N-formyl-methionyl-leucyl-phenylalanine-induced superoxide formation. In contrast, adenosine suppresses superoxide formation. Adenosine deaminase treatment abolished the suppressive effect of HS, indicating that HS inhibits neutrophils through adenosine generation. Neutrophils express mRNA, encoding all known P1 adenosine receptors (A1, A2a, A2b, and A3) and the nucleotide receptors P2Y2, P2Y4, P2Y6, P2Y11, and P2X7. A2 receptor agonists mimicked the suppressive effects of HS; the A2 receptor antagonists 8-(p-sulfophenyl)theophylline, 3,7-dimethyl-1-(2-propynyl)xanthine, 1,3,7-trimethyl-8-(3-chlorostyryl)xanthine, and 3-propylxanthine, but not A1 and A3 receptor antagonists, decreased the suppressive effect of HS, indicating that HS suppresses neutrophils via A2 receptor activation. Antagonists of P2 receptors counteracted the enhancing effects of ATP, suggesting that HS costimulates neutrophils by means of P2 receptor activation. We conclude that hypertonic stress regulates neutrophil function via a single molecule (ATP) and its metabolite (adenosine), using positive- and negative-feedback mechanisms through the activation of P2 and A2 receptors, respectively.
Collapse
Affiliation(s)
- Yu Chen
- Department of Surgery/Trauma, UCSD Medical Center, 200 West Arbor Drive, San Diego, CA 92103, USA
| | | | | | | | | |
Collapse
|
432
|
Wu K, Zhao Y, Li GC, Yu WP. c-Jun N-terminal kinase is required for vitamin E succinate-induced apoptosis in human gastric cancer cells. World J Gastroenterol 2004; 10:1110-4. [PMID: 15069708 PMCID: PMC4656343 DOI: 10.3748/wjg.v10.i8.1110] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
AIM: To investigate the roles of c-Jun N-terminal kinase (JNK) signaling pathway in vitamin E succinate-induced apoptosis in human gastric cancer SGC-7901 cells.
METHODS: Human gastric cancer cell lines (SGC-7901) were treated with vitamin E succinate (VES) at 5, 10, 20 mg/L. Succinic acid and vitamin E were used as vehicle controls and condition medium only as an untreated (UT) control. Apoptosis was observed by 4’, 6-diamidine-2’-phenylindole dihydrochloride (DAPI) staining for morphological changes and by DNA fragmentation for biochemical alterations. Western blot analysis was applied to measure the expression of JNK and phosphorylated JNK. After the cells were transiently transfected with dominant negative mutant of JNK (DN-JNK) followed by treatment of VES, the expression of JNK and c-Jun protein was determined.
RESULTS: The apoptotic changes were observed after VES treatment by DNA fragmentation. DNA ladder in the 20 mg/L VES group was more clearly seen than that in 10 mg/L VES group and was not detected following treatment of UT control, succinate and vitamin E. VES at 5, 10 and 20 mg/L increased the expression of p-JNK by 2.5-, 2.8- and 4.2-fold, respectively. VES induced the phosphorylation of JNK beginning at 1.5 h and produced a sustained increase for 24 h with the peak level at 12 h. Transient transfection of DN-JNK blocked VES-triggered apoptosis by 52%. DN-JNK significantly increased the level of JNK, while decreasing the expression of VES-induced c-Jun protein.
CONCLUSION: VES-induced apoptosis in human gastric cancer SGC-7901 cells involves JNK signaling pathway via c-Jun and its downstream transcription factor.
Collapse
Affiliation(s)
- Kun Wu
- Department of Nutrition and Food Hygiene, Public Health School, Harbin Medical University, Harbin 150001, Heilongjiang Province, China.
| | | | | | | |
Collapse
|
433
|
Tabakman R, Jiang H, Levine RA, Kohen R, Lazarovici P. Apoptotic characteristics of cell death and the neuroprotective effect of homocarnosine on pheochromocytoma PC12 cells exposed to ischemia. J Neurosci Res 2004; 75:499-507. [PMID: 14743433 DOI: 10.1002/jnr.20008] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We recently improved an in vitro ischemic model, using PC12 neuronal cultures exposed to oxygen-glucose deprivation (OGD) for 3 hr in a special device, followed by 18 hr of reoxygenation. The cell death induced in this ischemic model was evaluated by a series of markers: lactate dehydrogenase (LDH) release, caspase-3 activation, presence of cyclin D1, cytochrome c leakage from the mitochondria, BAX cellular redistribution, cleavage of poly (ADP-ribose) polymerase (PARP) to an 85-kDa apoptotic fragment, and DNA fragmentation. The OGD insult, in the absence of reoxygenation, caused a strong activation of the mitogen-activated protein kinase (MAPK) isoforms extracellular regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK), and stress-activated protein kinase (SAPK), also known as p-38. The detection of apoptotic markers and activation of MAPKs during the ischemic insult strongly suggest that apoptosis plays an important role in the PC12 cell death. Homocarnosine, a neuroprotective histidine dipeptide, present in high concentrations in the brain, was found to provide neuroprotection, as expressed by a 40% reduction in LDH release and caspase-3 activity at 1 mM. Homocarnosine reduced OGD activation of ERK 1, ERK 2, JNK 1, and JNK 2 by 40%, 46%, 55%, and 30%, respectively. These results suggest that apoptosis is an important characteristic of OGD-induced neuronal death and that antioxidants, such as homocarnosine, may prevent OGD-induced neuronal death by inhibiting the apoptotic process and/or in relation to the differential attenuation of activity of MAPKs.
Collapse
Affiliation(s)
- Rinat Tabakman
- Department of Pharmacology and Experimental Therapeutics, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | | | | | | | | |
Collapse
|
434
|
Yannoni YM, Gaestel M, Lin LL. P66ShcAinteracts with MAPKAP kinase 2 and regulates its activity. FEBS Lett 2004; 564:205-11. [PMID: 15094067 DOI: 10.1016/s0014-5793(04)00351-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2004] [Revised: 02/29/2004] [Accepted: 03/13/2004] [Indexed: 11/27/2022]
Abstract
Three mitogen activated protein kinase-activated protein kinase 2 (MAPKAP kinase 2, MK2) interacting proteins were identified using a yeast two-hybrid approach. ShcA, a signaling phospho-protein, human polyhomeotic 2 (HPH2), a transcriptional regulator, and highly similar to smoothelin (HSTS), which is related to the cytoskeletal associated protein smoothelin, interact specifically with MK2. The interaction of MK2 with the 66 kDa isoform of ShcA, p66(ShcA), and HPH2 was confirmed using co-immunoprecipitation. MK2 is activated with p66(ShcA) co-expression and p66(ShcA) is an in vitro substrate for MK2, further demonstrating their association and suggesting a biological role for p66(Shc) in MK2 activation.
Collapse
Affiliation(s)
- Yvonne M Yannoni
- Department of Inflammation, Wyeth Research, 200 Cambridge Park Drive, Cambridge, MA 02140-2311, USA.
| | | | | |
Collapse
|
435
|
Wang D, Lippard SJ. Cisplatin-induced post-translational modification of histones H3 and H4. J Biol Chem 2004; 279:20622-5. [PMID: 15010460 DOI: 10.1074/jbc.m402547200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The anti-cancer drug cisplatin kills cells by damaging DNA and inducing apoptosis. Understanding the detailed mechanisms by which cancer cells respond to cisplatin has the potential to improve substantially platinum-based therapy. Post-translational modification of histones alters chromatin structure, facilitating the binding of nuclear factors that mediate DNA repair, transcription, and other processes. In the present study, we have investigated the effects of cisplatin treatment on histone post-translational modification in cancer cells. We discovered that specific phosphorylation of histone H3 at Ser-10, mediated by the p38 MAPK pathway, is induced in response to cisplatin treatment. In addition, hyperacetylation of histone H4 was caused by drug treatment. These findings revealed a link between cisplatin administration and chromosomal structural alterations, providing mechanistic information about how cells respond to platinum-induced stress.
Collapse
Affiliation(s)
- Dong Wang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | | |
Collapse
|
436
|
Usatyuk PV, Vepa S, Watkins T, He D, Parinandi NL, Natarajan V. Redox regulation of reactive oxygen species-induced p38 MAP kinase activation and barrier dysfunction in lung microvascular endothelial cells. Antioxid Redox Signal 2003; 5:723-30. [PMID: 14588145 DOI: 10.1089/152308603770380025] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Reactive oxygen species (ROS)-mediated compromise of endothelial barrier integrity has been implicated in a number of pulmonary disorders, including adult respiratory distress syndrome, pulmonary edema, and vasculitis. The mechanisms by which ROS increase endothelial permeability are unclear. We hypothesized that ROS-induced changes in cellular redox status (thiols) may contribute to endothelial barrier dysfunction. To test this hypothesis, we used N-acetylcysteine (NAC) and diamide to modulate intracellular levels of cellular glutathione (GSH) and investigated hydrogen peroxide (H(2)O(2))-mediated mitogen-activated protein kinase (MAPK) activation and transendothelial electrical resistance (TER). Exposure of bovine lung microvascular endothelial cells (BLMVECs) to H(2)O(2), in a dose- and time-dependent fashion, increased endothelial permeability. Pretreatment of BLMVECs with NAC (5 mM) for 1 h resulted in partial attenuation of H(2)O(2)-induced TER (a measure of increase in permeability) and GSH. Furthermore, treatment of BLMVECs with diamide, which is known to reduce the intracellular GSH, resulted in significant reduction in TER, which was prevented by NAC. To understand further the role of MAPKs in ROS-induced barrier dysfunction, we examined the role of extracellular signal-regulated kinase (ERK) and p38 MAPK on H(2)O(2)- and diamide-mediated permeability changes. Both H(2)O(2) and diamide, in a dose-dependent manner, activated ERK and p38 MAPK in BLMVECs. However, SB203580, an inhibitor of p38 MAPK, but not PD98059, blocked H(2)O(2)- and diamide-induced TER. Also, NAC prevented H(2)O(2)- and diamide-induced p38 MAPK, but not ERK activation. These results suggest a role for redox regulation of p38 MAPK in ROS-dependent endothelial barrier dysfunction.
Collapse
Affiliation(s)
- Peter V Usatyuk
- Department of Medicine, Division of Pulmonary and Critical Care, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA
| | | | | | | | | | | |
Collapse
|
437
|
Abstract
At Aplysia sensory-to-motor neuron synapses, the inhibitory neuropeptide Phe-Met-Arg-Phe-NH2 (FMRFa) produces depression, and serotonin (5-HT) produces facilitation. Short-term depression has been found to result from the activation of a phospholipase A2. The released arachidonate is metabolized by 12-lipoxygenase to active second messengers. We find that FMRFa leads to the phosphorylation and activation of p38 mitogen-activated protein (MAP) kinase. Short-term depression and the release of arachidonate are blocked by the specific p38 kinase inhibitor SB 203580. Both the inhibitor and an affinity-purified antibody raised against recombinant Aplysia p38 kinase injected into sensory neurons prevented long-term depression, which depends on the phosphorylation of translation factors cAMP response element-binding protein 2 (CREB2) and activating transcription factor 2. Facilitation produced by 5-HT, on the other hand, inactivates p38 kinase. Chromatin immunoprecipitation assays indicate that p38 kinase activates CREB2. p38 kinase also is pivotal in the bidirectional regulation of synaptic plasticity: when the kinase is inhibited, brief treatment with 5-HT that normally produces only short-term facilitation now results in long-term facilitation. Conversely, in sensory neurons injected with the activated kinase, long-term facilitation is blocked, and brief exposure to FMRFa, which normally results in short-term depression, results in long-term depression. We conclude that p38 kinase, which itself is bidirectionally regulated by FMRFa and 5-HT, acts as a modulator of synaptic plasticity by positively regulating depression and serving as an inhibitory constraint for facilitation.
Collapse
|