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Zhang S, Qi H, Wen X, Li P, Gao X, Ao J. The phosphorylation of Tudor‐SN mediated by JNK is involved in the regulation of milk protein synthesis induced by prolactin in BMECs. J Cell Physiol 2018; 234:6077-6090. [DOI: 10.1002/jcp.27343] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 08/10/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Sen Zhang
- Department of Biochemistry and Molecular Biology Key Laboratory of Agricultural Biological Functional Gene of Heilongjiang Province, Northeast Agricultural University Harbin China
| | - Hao Qi
- Department of Biochemistry and Molecular Biology Key Laboratory of Agricultural Biological Functional Gene of Heilongjiang Province, Northeast Agricultural University Harbin China
| | - Xue‐Peng Wen
- Department of Biochemistry and Molecular Biology Key Laboratory of Agricultural Biological Functional Gene of Heilongjiang Province, Northeast Agricultural University Harbin China
| | - Ping Li
- Department of Biochemistry and Molecular Biology Key Laboratory of Agricultural Biological Functional Gene of Heilongjiang Province, Northeast Agricultural University Harbin China
| | - Xue‐Jun Gao
- Department of Biochemistry and Molecular Biology Key Laboratory of Agricultural Biological Functional Gene of Heilongjiang Province, Northeast Agricultural University Harbin China
| | - Jin‐Xia Ao
- Department of Biochemistry and Molecular Biology Key Laboratory of Agricultural Biological Functional Gene of Heilongjiang Province, Northeast Agricultural University Harbin China
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Yang TC, Wu PC, Chung IF, Jiang JH, Fann MJ, Kao LS. Cell death caused by the synergistic effects of zinc and dopamine is mediated by a stress sensor gene Gadd45b - implication in the pathogenesis of Parkinson's disease. J Neurochem 2016; 139:120-33. [PMID: 27385273 DOI: 10.1111/jnc.13728] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 07/01/2016] [Accepted: 07/03/2016] [Indexed: 11/30/2022]
Abstract
The pathogenesis of Parkinson's disease (PD) is not completely understood, Zinc (Zn(2+) ) and dopamine (DA) have been shown to involve in the degeneration of dopaminergic cells. By microarray analysis, we identified Gadd45b as a candidate molecule that mediates Zn(2+) and DA-induced cell death; the mRNA and protein levels of Gadd45b are increased by Zn(2+) treatment and raised to an even higher level by Zn(2+) plus DA treatment. Zn(2+) plus DA treatment-induced PC12 cell death was enhanced when there was over-expression of Gadd45b and was decreased by knock down of Gadd45b. MAPK p38 and JNK signaling was able to cross-talk with Gadd45b during Zn(2+) and DA treatment. The synergistic effects of Zn(2+) and DA on PC12 cell death can be accounted for by an activation of the Gadd45b-induced cell death pathway and an inhibition of p38/JNK survival pathway. Furthermore, the in vivo results show that the levels of Gadd45b protein expression and phosphorylation of p38 were increased in the substantia nigra by the infusion of Zn(2+) /DA in the mouse brain and the level of Gadd45b mRNA is significantly higher in the substantia nigra of male PD patients than normal controls. The novel role of Gadd45b and its interactions with JNK and p38 will help our understanding of the pathogenesis of PD and help the development of future treatments for PD. Zinc and dopamine are implicated in the degeneration of dopaminergic neurons. We previously demonstrated that zinc and dopamine induced synergistic effects on PC12 cell death. Results from this study show that these synergistic effects can be accounted for by activation of the Gadd45b-induced cell death pathway and inhibition of the p38/JNK survival pathway. We provide in vitro and in vivo evidence to support a novel role for Gadd45b in the pathogenesis of Parkinson's disease.
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Affiliation(s)
- Tien-Chun Yang
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Pei-Chun Wu
- Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - I-Fang Chung
- Institute of Biomedical Informatics, National Yang-Ming University, Taipei, Taiwan
| | - Jhih-Hang Jiang
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Ming-Ji Fann
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Lung-Sen Kao
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan. .,Brain Research Center, National Yang-Ming University, Taipei, Taiwan.
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Tsirimonaki E, Fedonidis C, Pneumaticos SG, Tragas AA, Michalopoulos I, Mangoura D. PKCε signalling activates ERK1/2, and regulates aggrecan, ADAMTS5, and miR377 gene expression in human nucleus pulposus cells. PLoS One 2013; 8:e82045. [PMID: 24312401 PMCID: PMC3842981 DOI: 10.1371/journal.pone.0082045] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 10/29/2013] [Indexed: 12/25/2022] Open
Abstract
The protein kinase C (PKC) signaling, a major regulator of chondrocytic differentiation, has been also implicated in pathological extracellular matrix remodeling, and here we investigate the mechanism of PKCε-dependent regulation of the chondrocytic phenotype in human nucleus pulposus (NP) cells derived from herniated disks. NP cells from each donor were successfully propagated for 25+ culture passages, with remarkable tolerance to repeated freeze-and-thaw cycles throughout long-term culturing. More specifically, after an initial downregulation of COL2A1, a stable chondrocytic phenotype was attested by the levels of mRNA expression for aggrecan, biglycan, fibromodulin, and lumican, while higher expression of SOX-trio and Patched-1 witnessed further differentiation potential. NP cells in culture also exhibited a stable molecular profile of PKC isoforms: throughout patient samples and passages, mRNAs for PKC α, δ, ε, ζ, η, ι, and µ were steadily detected, whereas β, γ, and θ were not. Focusing on the signalling of PKCε, an isoform that may confer protection against degeneration, we found that activation with the PKCε-specific activator small peptide ψεRACK led sequentially to a prolonged activation of ERK1/2, increased abundance of the early gene products ATF, CREB1, and Fos with concurrent silencing of transcription for Ki67, and increases in mRNA expression for aggrecan. More importantly, ψεRACK induced upregulation of hsa-miR-377 expression, coupled to decreases in ADAMTS5 and cleaved aggrecan. Therefore, PKCε activation in late passage NP cells may represent a molecular basis for aggrecan availability, as part of an PKCε/ERK/CREB/AP-1-dependent transcriptional program that includes upregulation of both chondrogenic genes and microRNAs. Moreover, this pathway should be considered as a target for understanding the molecular mechanism of IVD degeneration and for therapeutic restoration of degenerated disks.
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Affiliation(s)
| | | | - Spiros G. Pneumaticos
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
- Department of Orthopedics, Athens Medical School, University of Athens, Athens, Greece
| | | | | | - Dimitra Mangoura
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
- * E-mail:
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PKC-epsilon activation is required for recognition memory in the rat. Behav Brain Res 2013; 253:280-9. [PMID: 23911427 DOI: 10.1016/j.bbr.2013.07.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 07/18/2013] [Accepted: 07/22/2013] [Indexed: 11/20/2022]
Abstract
Activation of PKCɛ, an abundant and developmentally regulated PKC isoform in the brain, has been implicated in memory throughout life and across species. Yet, direct evidence for a mechanistic role for PKCɛ in memory is still lacking. Hence, we sought to evaluate this in rats, using short-term treatments with two PKCɛ-selective peptides, the inhibitory ɛV1-2 and the activating ψɛRACK, and the novel object recognition task (NORT). Our results show that the PKCɛ-selective activator ψɛRACK, did not have a significant effect on recognition memory. In the short time frames used, however, inhibition of PKCɛ activation with the peptide inhibitor ɛV1-2 significantly impaired recognition memory. Moreover, when we addressed at the molecular level the immediate proximal signalling events of PKCɛ activation in acutely dissected rat hippocampi, we found that ψɛRACK increased in a time-dependent manner phosphorylation of MARCKS and activation of Src, Raf, and finally ERK1/2, whereas ɛV1-2 inhibited all basal activity of this pathway. Taken together, these findings present the first direct evidence that PKCɛ activation is an essential molecular component of recognition memory and point toward the use of systemically administered PKCɛ-regulating peptides as memory study tools and putative therapeutic agents.
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Kuang Y, Xu B. Disruption of the dynamics of microtubules and selective inhibition of glioblastoma cells by nanofibers of small hydrophobic molecules. Angew Chem Int Ed Engl 2013; 52:6944-8. [PMID: 23686848 PMCID: PMC3771361 DOI: 10.1002/anie.201302658] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Yi Kuang
- Department of Chemistry Brandeis University 415 South Street, Waltham, MA 02453
| | - Bing Xu
- Department of Chemistry Brandeis University 415 South Street, Waltham, MA 02453
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Kuang Y, Xu B. Disruption of the Dynamics of Microtubules and Selective Inhibition of Glioblastoma Cells by Nanofibers of Small Hydrophobic Molecules. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201302658] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Yousefi B, Ghaderi S, Rezapoor-Lactooyi A, Amiri N, Verdi J, Shoae-Hassani A. Hydroxy decenoic acid down regulates gtfB and gtfC expression and prevents Streptococcus mutans adherence to the cell surfaces. Ann Clin Microbiol Antimicrob 2012; 11:21. [PMID: 22839724 PMCID: PMC3495742 DOI: 10.1186/1476-0711-11-21] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 07/08/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND 10-Hydroxy-2-decenoic acid, an unsaturated fatty acid is the most active and unique component to the royal jelly that has antimicrobial properties. Streptococcus mutans is associated with pathogenesis of oral cavity, gingivoperiodontal diseases and bacteremia following dental manipulations. In the oral cavity, S. mutans colonize the soft tissues including tongue, palate, and buccal mucosa. When considering the role of supragingival dental plaque in caries, the proportion of acid producing bacteria (particularly S. mutans), has direct relevance to the pathogenicity of the plaque. The genes that encode glucosyltransferases (gtfs) especially gtfB and gtfC are important in S. mutans colonization and pathogenesis. This study investigated the hydroxy-decenoic acid (HDA) effects on gtfB and gtfC expression and S. mutans adherence to cells surfaces. METHODS Streptococcus mutans was treated by different concentrations of HPLC purified HDA supplied by Iran Beekeeping and Veterinary Association. Real time RT-PCR and western blot assays were conducted to evaluate gtfB and gtfC genes transcription and translation before and after HDA treatment. The bacterial attachment to the cell surfaces was evaluated microscopically. RESULTS 500 μg ml-1 of HDA inhibited gtfB and gtfC mRNA transcription and its expression. The same concentration of HDA decreased 60% the adherence of S. mutans to the surface of P19 cells. CONCLUSION Hydroxy-decenoic acid prevents gtfB and gtfC expression efficiently in the bactericide sub-concentrations and it could effectively reduce S. mutans adherence to the cell surfaces. In the future, therapeutic approaches to affecting S. mutans could be selective and it's not necessary to put down the oral flora completely.
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Affiliation(s)
- Behnam Yousefi
- School of Advanced Medical Technologies, Tehran University of Medical Sciences (TUMS), Tehran, Iran
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Asimaki O, Leondaritis G, Lois G, Sakellaridis N, Mangoura D. Cannabinoid 1 receptor-dependent transactivation of fibroblast growth factor receptor 1 emanates from lipid rafts and amplifies extracellular signal-regulated kinase 1/2 activation in embryonic cortical neurons. J Neurochem 2011; 116:866-73. [DOI: 10.1111/j.1471-4159.2010.07030.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Asimaki O, Mangoura D. Cannabinoid receptor 1 induces a biphasic ERK activation via multiprotein signaling complex formation of proximal kinases PKCε, Src, and Fyn in primary neurons. Neurochem Int 2010; 58:135-44. [PMID: 21074588 DOI: 10.1016/j.neuint.2010.11.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 11/02/2010] [Accepted: 11/03/2010] [Indexed: 11/17/2022]
Abstract
Cannabinoid receptors 1 (CB1Rs) play important roles in the regulation of dendritic branching, synapse density, and synaptic transmission through multiple G-protein-coupled signaling systems, including the activation of the extracellular signal-regulated kinases ERK1/2. The proximal signaling interactions leading to ERK1/2 activation by CB1R in CNS remain, however, unclear. Here, we present evidence that the CB1R agonist methanandamide induced a biphasic and sustained activation of ERK1/2 in primary neurons derived from E7 telencephalon. We show that E7 neurons natively express high levels of CB1R message and protein, the majority of which associates with PKCɛ at basal conditions. We now demonstrate that the first peak of ERK activation by CB1R was mediated by the sequential activation of G(q), PLC, and PKCɛ, selectively, and that the CB1R-activated PKCɛ acutely formed transient signaling modules containing activated Src and Fyn. A second pool of CB1Rs, coupled to PTX-sensitive activation of G(i/o), utilized as effectors additional Src and Fyn molecules to generate a second, additional wave of ERK activation at 15 min. Concurrently to these intermolecular signaling interactions, cytoskeleton-associated proteins MARCKS and p120catenin were drastically modified by phosphorylation of PKC and Src, respectively. These receptor-proximal signaling events correlated well with induction of neuritic outgrowth in the long term. Our data provide evidence for multiprotein signaling complex formation in the coupling of CB1R to activation of ERK in CNS neurons, and may elucidate several of the less understood acute effects of cannabinoid drugs.
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Affiliation(s)
- Olga Asimaki
- Developmental Neurobiology and Neurochemistry Group, Basic Neurosciences, Center for Preventive Medicine, Neurosciences and Social Psychiatry, Biomedical Research Foundation of the Academy of Athens, 4, Soranou Ephessiou Street, 11527 Athens, Greece
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Prolactin prevents chronic stress-induced decrease of adult hippocampal neurogenesis and promotes neuronal fate. J Neurosci 2009; 29:1826-33. [PMID: 19211889 DOI: 10.1523/jneurosci.3178-08.2009] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Chronic exposure to stress results in a reduction of hippocampal neurogenesis and of hippocampal volume. We examined whether prolactin (PRL), a regulator of the stress response and stimulator of neurogenesis in the subventricular zone, influences neurogenesis in the hippocampal dentate gyrus (DG) of chronically stressed adult C57BL/6 male mice. Chronically stressed (4 h daily immobilization for 21 d) or nonstressed mice were treated with either ovine PRL or vehicle between days 1-14. BrdU was injected daily between days 1-7 to evaluate cell survival and fate, or twice on day 21 to evaluate cell proliferation. Hippocampal cell proliferation was unchanged by either stress exposure or PRL at the end of the treatments. In contrast, the number of cells in the DG that incorporated BrdU during the first phase of the experiment and survived to the end of the experiment was decreased in vehicle-treated stressed mice compared with PRL- or vehicle-treated nonstressed control mice. Stressed animals receiving PRL had significantly more BrdU-labeled cells than vehicle-treated stressed mice at this time point. Cell fate analysis revealed a higher percentage of neurons in PRL- compared with vehicle-treated stressed mice. The results demonstrate that PRL protects neurogenesis in the DG of chronically stressed mice and promotes neuronal fate.
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Theofilopoulos S, Lykidis A, Leondaritis G, Mangoura D. Novel function of the human presqualene diphosphate phosphatase as a type II phosphatidate phosphatase in phosphatidylcholine and triacylglyceride biosynthesis pathways. Biochim Biophys Acta Mol Cell Biol Lipids 2008; 1781:731-42. [DOI: 10.1016/j.bbalip.2008.09.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Revised: 08/29/2008] [Accepted: 09/11/2008] [Indexed: 11/27/2022]
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12
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Swaminathan G, Varghese B, Fuchs SY. Regulation of prolactin receptor levels and activity in breast cancer. J Mammary Gland Biol Neoplasia 2008; 13:81-91. [PMID: 18204982 PMCID: PMC2276629 DOI: 10.1007/s10911-008-9068-6] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Accepted: 01/02/2008] [Indexed: 11/29/2022] Open
Abstract
From its traditional identity as a hormone involved in growth and differentiation of mammary epithelium and in lactation, to having a pertinent role in the development of mammary carcinoma, the peptide hormone/cytokine prolactin (PRL) has emerged as a versatile signaling molecule. There has been significant progress in our understanding of the fine working of PRL in the past several years. Notably, much effort has been concentrated on the mediator of PRL action, namely, the prolactin receptor (PRLr). The causal link between increased PRLr expression and breast cancer is being increasingly appreciated. Considering that the level of the receptor on the surface is a critical determinant of signaling output in response to PRL, the uncovering of regulatory elements that control receptor expression becomes important. The principle focus of this review is on the regulation of PRLr expression and activity in breast cancer with a brief overview of different isoforms of PRLr, their expression, signaling capabilities and the biological outcomes of PRL/PRLr signaling.
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Affiliation(s)
- G Swaminathan
- Department of Animal Biology and Mari Lowe Center for Comparative Oncology Research, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - B Varghese
- Department of Animal Biology and Mari Lowe Center for Comparative Oncology Research, University of Pennsylvania, Philadelphia, PA 19104, USA
- Cell and Molecular Biology Program, Biomedical Graduate School, University of Pennsylvania, PA 19104, USA
| | - SY Fuchs
- Department of Animal Biology and Mari Lowe Center for Comparative Oncology Research, University of Pennsylvania, Philadelphia, PA 19104, USA
- Address correspondence to: Dr. Serge Y. Fuchs, Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, 380 S. University Ave, Hill 316, Philadelphia, PA 19104. (215)-573-6949 (phone), (215)-746-2295 (fax), (email)
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Hattori N, Nomoto H, Fukumitsu H, Mishima S, Furukawa S. AMP N(1)-oxide, a unique compound of royal jelly, induces neurite outgrowth from PC12 cells via signaling by protein kinase A independent of that by mitogen-activated protein kinase. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2007; 7:63-8. [PMID: 18955270 PMCID: PMC2816379 DOI: 10.1093/ecam/nem146] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2007] [Accepted: 08/20/2007] [Indexed: 01/08/2023]
Abstract
Earlier we identified adenosine monophosphate (AMP) N1-oxide as a unique compound of royal jelly (RJ) that induces neurite outgrowth (neuritegenesis) from cultured rat pheochromocytoma PC12 cells via the adenosine A2A receptor. Now, we found that AMP N1-oxide stimulated the phosphorylation of not only mitogen-activated protein kinase (MAPK) but also that of cAMP/calcium-response element-binding protein (CREB) in a dose-dependent manner. Inhibition of MAPK activation by a MEK inhibitor, PD98059, did not influence the AMP N1-oxide-induced neuritegenesis, whereas that of protein kinase A (PKA) by a selective inhibitor, KT5720, significantly reduced neurite outgrowth. AMP N1-oxide also had the activity of suppressing the growth of PC12 cells, which correlated well with the neurite outgrowth-promoting activity. KT5720 restored the growth of AMP N1-oxide-treated PC12 cells. It is well known that nerve growth factor suppresses proliferation of PC12 cells before causing stimulation of neuronal differentiation. Thus, AMP N1-oxide elicited neuronal differentiation of PC12 cells, as evidenced by generation of neurites, and inhibited cell growth through adenosine A2A receptor-mediated PKA signaling, which may be responsible for characteristic actions of RJ.
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Affiliation(s)
- Noriko Hattori
- Laboratory of Molecular Biology, Gifu Pharmaceutical University, Mitahora-higashi, Gifu 502-8585, Japan and Nagaragawa Research Center, API Co., Ltd, Nagara, Gifu 502-0071, Japan
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Tai TC, Wong-Faull DC, Claycomb R, Wong DL. Nerve Growth Factor Regulates Adrenergic Expression. Mol Pharmacol 2006; 70:1792-801. [PMID: 16926281 DOI: 10.1124/mol.106.026237] [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: 11/22/2022] Open
Abstract
The mechanism by which nerve growth factor (NGF) regulates adrenergic expression was examined in PC-12 cells transfected with a rat phenylethanolamine N-methyl-transferase (PNMT) promoter-luciferase reporter gene construct pGL3RP893. NGF treatment increased PNMT promoter-driven luciferase activity in a dose- and time-dependent manner. Induction was attenuated by inhibition of the extracellular signal-regulated kinase mitogen-activated protein kinase (MAPK) pathway ( approximately 60%) but not by inhibition of the protein kinase A (PKA), protein kinase C, phosphoinositol kinase, or p38 MAPK pathways. Deletion PNMT promoter-luciferase reporter gene constructs showed that the NGF-responsive sequences lay within the proximal -392 base pairs (bp) of PNMT promoter, wherein binding elements for Egr-1 (-165 bp) and Sp1 (-48 bp) reside. Western analysis further showed that NGF increased nuclear levels of Egr-1, but not Sp1 or the catalytic subunit of PKA. Gel mobility shift assays showed increased potential for Egr-1, but not Sp1, protein-DNA binding complex formation. Mutation of either the Egr-1 or Sp1 binding sites in the PNMT promoter attenuated NGF activation. NGF, combined with pituitary adenylyl cyclase-activating protein (PACAP), another PNMT transcriptional activator, cooperatively stimulated PNMT promoter driven-luciferase activity beyond levels observed with either neurotrophin alone. Finally, post-transcriptional control seems to be another important mechanism by which neurotrophins regulate the adrenergic phenotype. NGF, PACAP, and a combination of the two stimulated both intron-retaining and intronless PNMT mRNA and PNMT protein, but to different extents.
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Affiliation(s)
- T C Tai
- Laboratory of Molecular and Developmental Neurobiology, Department of Psychiatry, McLean Hospital, Harvard Medical School, 115 Mill St., MRC 116, Belmont, MA 02478, USA
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McLaughlin D, Tsirimonaki E, Vallianatos G, Sakellaridis N, Chatzistamatiou T, Stavropoulos-Gioka C, Tsezou A, Messinis I, Mangoura D. Stable expression of a neuronal dopaminergic progenitor phenotype in cell lines derived from human amniotic fluid cells. J Neurosci Res 2006; 83:1190-200. [PMID: 16555279 DOI: 10.1002/jnr.20828] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Cells from human amniotic fluid derived from the fetus are considered a source of multipotent cells. Their properties have not been fully exploited, partially because unlike other embryonic sources such as embryonic stem (ES) cells, cell lines from amniocentesis samples have not been generated. We have established and characterized the properties of eight individual cell lines. Flow cytometry using several cell surface markers showed that all cell lines generated consisted of homogeneous populations that lack HLAII antigenicity. Using a combination of immunocytochemistry, Western blotting, and RT-PCR, we found weak expression of Oct4 and nestin and strong expression of tubulin-betaIII, MAP2, and tau. Specific markers for cholinergic, (nor)adrenergic, and GABAergic neurons or glia were weakly expressed or absent, whereas expression of factors implicated in early induction of dopaminergic neurons, TGF-beta3 and beta-catenin were present. Further analysis showed strong expression of EN-1, c-RET, PTX3, and NURR1 essential for induction and survival of midbrain dopaminergic neurons, TH, AADC, and VMAT2 components of dopamine synthesis and secretion, and syntaxin1A and SNAP-25 necessary for neurotransmitter exocytosis. This phenotype was retained throughout passages and up to the current passage 36. Expression of neuronal and dopaminergic markers in individual AF cell lines was comparable to expression in neurons induced from ES cells and in IMR-32 and SH-SY5Y neuroblastomas. Our data show that cell lines can be derived from subcultures of amniocentesis, and are primarily composed of a population of progenitors with a phenotype similar to that of committed mesencephalic dopaminergic neurons.
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Affiliation(s)
- David McLaughlin
- Neuroscience Division, Institute for Biomedical Research of the Academy of Athens, Athens, Greece
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Jeon HK, Choi SU, Jung NP. Association of the ERK1/2 and p38 kinase pathways with nitric oxide-induced apoptosis and cell cycle arrest in colon cancer cells. Cell Biol Toxicol 2006; 21:115-25. [PMID: 16142585 DOI: 10.1007/s10565-005-0148-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2004] [Accepted: 05/03/2005] [Indexed: 12/16/2022]
Abstract
To investigate the mechanism by which nitric oxide (NO) induces cell death in colon cancer cells, we compared two types of colon cancer cells with different p53 status: HCT116 (p53 wild-type) cells and SW620 (p53-deficient) cells. We found that S-nitrosoglutathione (GSNO), the NO donor, induced apoptosis in both types of colon cancer cells. However, SW620 cells were much more susceptible than HCT116 cells to apoptotic death by NO. We investigated the role of extracellular signal-regulated kinase 1/2 (ERK1/2) and p38 kinase on NO-induced apoptosis in both types of colon cancer cells. GSNO treatment effectively stimulated activation of the ERK1/2 and p38 kinase in both types of cells. In HCT116 cells, pretreatment with PD98059, an inhibitor of ERK1/2, or SB203580, an inhibitor of p38 kinase, had no marked effect on GSNO-induced apoptosis. However, in SW620 cells, SB203580 significantly reduced the NO-induced apoptosis, whereas PD098059 increases NO-induced apoptosis. Furthermore, we found evidence of cell cycle arrest of the G0/G1 phase in SW620 cells but not in HCT116 cells. Inhibition of ERK1/2 with PD098059, or of p38 kinase with SB203580, reduced the GSNO-induced cell cycle arrest of the G0/G1 phase in SW620 cells. We therefore conclude that NO-induced apoptosis in colon cancer cells is mediated by a p53-independent mechanism and that the pathways of ERK1/2 and p38 kinase are important in NO-induced apoptosis and in the cell cycle arrest of the G0/G1 phase.
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Affiliation(s)
- H-K Jeon
- Department of Biology, Yonsei University, Seoul, Korea.
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Mangoura D, Sun Y, Li C, Singh D, Gutmann DH, Flores A, Ahmed M, Vallianatos G. Phosphorylation of neurofibromin by PKC is a possible molecular switch in EGF receptor signaling in neural cells. Oncogene 2006; 25:735-45. [PMID: 16314845 DOI: 10.1038/sj.onc.1209113] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Children with neurofibromatosis (NF1) typically develop central nervous system (CNS) abnormalities, including aberrant proliferation of astrocytes and formation of benign astrocytomas. The NF1 gene encodes neurofibromin, a Ras-GAP, highly expressed in developing neural cells; the mechanism of regulation of neurofibromin as a Ras-GAP, remains however unknown. We now show that, in response to EGF, neurofibromin is in vivo phosphorylated on serine residues by PKC-alpha, in human, rat, and avian CNS cells and cell lines. EGF-induced PKC phosphorylation was prominent in the cysteine/serine-rich domain (CSRD) of neurofibromin, which lies in the N-terminus and upstream of the Ras-GAP domain (GRD), and this modification significantly increased the association of neurofibromin with actin in co-immunoprecipitations. In addition, we show that Ras activation in response to EGF was significantly lowered when C62B cells overexpressed a construct encoding both CSRD + GRD. Moreover, when PKC-alpha was downregulated, the Ras-GAP activity of CSRD + GRD was significantly diminished, whereas overexpressed GRD alone acted as a weaker GAP and in a PKC-independent manner. Most importantly, functional Ras inhibition and EGF signaling shifts were established at the single cell level in C6-derived cell lines stably overexpressing CSRD + GRD, when transient co-overexpression of Ras and PKC-depletion prior to stimulation with EGF-induced mitosis. Taken together, these data provide the first evidence of a functional, allosteric regulation of GRD by CSRD, which requires neurofibromin phosphorylation by PKC and association with the actin cytoskeleton. Our data may suggest a novel mechanism for regulating biological responses to EGF and provide a new aspect for the understanding of the aberrant proliferation seen in the CNS of children with NF1.
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Affiliation(s)
- D Mangoura
- Department of Pediatrics, The University of Chicago, Chicago, IL, USA. and Neurosciences Division, Institute for Biomedical Research, Athens, Greece
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Cabrales-Romero MDP, Márquez-Rosado L, Fattel-Fazenda S, Trejo-Solís C, Arce-Popoca E, Alemán-Lazarini L, Villa-Treviño S. S-adenosyl-methionine decreases ethanol-induced apoptosis in primary hepatocyte cultures by a c-Jun N-terminal kinase activity-independent mechanism. World J Gastroenterol 2006; 12:1895-904. [PMID: 16609996 PMCID: PMC4087515 DOI: 10.3748/wjg.v12.i12.1895] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To determine the role of c-Jun N-terminal kinase (JNK) activity in ethanol-induced apoptosis and the modulation of this signaling cascade by S-Adenosyl-methionine (AdoMet).
METHODS: Primary hepatocyte cultures were pretreated with 100 µmol/L SP600125, a selective JNK inhibitor, 1 mL/L DMSO or 4 mmol/L AdoMet and then exposed to 100 mmo/L ethanol. Hepatocyte apoptosis was determined by the TUNEL and DNA ladder assays. JNK activity and its inhibition by SP600125 and AdoMet were determined by Western blot analysis of c-jun phosphorylation and Bid fragmentation. SP600125 and AdoMet effects on the apoptotic signaling pathway were determined by Western blot analysis of cytochrome c release and pro-caspase 3 fragmentation. The AdoMet effect on glutathione levels was measured by Ellman’s method and reactive oxygen species (ROS) generation by cell cytometry.
RESULTS: The exposure of hepatocytes to ethanol induced JNK activation, c-jun phosphorylation, Bid fragmentation, cytochrome c release and pro-caspase 3 cleavage; these effects were diminished by SP600125, and caused a significant decrease in ethanol-induced apoptosis (P< 0.05). AdoMet exerted an antioxidant effect maintaining glutathione levels and decreasing ROS generation, without a significant effect on JNK activity, and prevented cytochrome c release and pro-caspase 3 cleavage.
CONCLUSION: The JNK signaling cascade is a key component of the proapoptotic signaling pathway induced by ethanol. JNK activation may be independent from ROS generation, since AdoMet which exerted antioxidant properties did not have a significant effect on JNK activity. JNK pathway modulator agents and AdoMet may be components of promising therapies for alcoholic liver disease (ALD) treatment.
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Stocks MJ, Barber S, Ford R, Leroux F, St-Gallay S, Teague S, Xue Y. Structure-driven HtL: design and synthesis of novel aminoindazole inhibitors of c-Jun N-terminal kinase activity. Bioorg Med Chem Lett 2005; 15:3459-62. [PMID: 15950471 DOI: 10.1016/j.bmcl.2005.05.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2005] [Revised: 04/25/2005] [Accepted: 05/02/2005] [Indexed: 11/19/2022]
Abstract
The design and synthesis of a new series of c-Jun N-terminal kinase inhibitors are reported. The novel series of substituted amino indazoles were designed based on a combination of hits from high-throughput screening and X-ray crystal structure information of the compounds crystallised into the JNK-1 ATP binding site.
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Affiliation(s)
- Michael J Stocks
- Department of Medicinal Chemistry, AstraZeneca R&D Charnwood, Bakewell Road, Loughborough LE11 5RH, UK.
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20
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Carreño PC, Sacedón R, Jiménez E, Vicente A, Zapata AG. Prolactin affects both survival and differentiation of T-cell progenitors. J Neuroimmunol 2005; 160:135-45. [PMID: 15710466 DOI: 10.1016/j.jneuroim.2004.11.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2004] [Revised: 11/12/2004] [Accepted: 11/12/2004] [Indexed: 12/30/2022]
Abstract
We have analysed the in vitro effects of prolactin on thymocyte development concluding that PRL favours the survival and differentiation of T-cell progenitors. Fetal, adult thymocytes and CD45(+) fetal liver lymphoid progenitors express PRL-R. PRL induces survival, proliferation and differentiation of lymphoid progenitors whereas both an anti-PRL antiserum and an anti-PRL-R mAb block T-cell development accumulating CD25(+)DN (CD4(-)CD8(-)) cells. Furthermore, IL2 rescues the blockade of T-cell development in FTOC treated with anti-PRL antiserum but PRL does not recover cultures treated with an anti-IL2R alpha chain mAb, which drastically blocks the T-cell development. These results support IL2/IL2R mediation of PRL effects on developing thymocytes.
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Affiliation(s)
- Paz C Carreño
- Department of Cell Biology, Faculty of Biology, Complutense University, 28040 Madrid, Spain
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21
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GUTZMAN JENNIFERH, RUGOWSKI DEBRAE, SCHROEDER MATTHEWD, WATTERS JYOTIJ, SCHULER LINDAA. Multiple kinase cascades mediate prolactin signals to activating protein-1 in breast cancer cells. Mol Endocrinol 2004; 18:3064-75. [PMID: 15319452 PMCID: PMC1634796 DOI: 10.1210/me.2004-0187] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The importance of prolactin (PRL) in physiological proliferation and differentiation of the mammary gland, together with high levels of PRL receptors in breast tumors, the association of circulating PRL with incidence of breast cancer, and the recognition of locally produced PRL, point to the need for greater understanding of PRL actions in mammary disease. Although PRL has been shown to activate multiple kinase cascades in various target cells, relatively little is known of its signaling pathways in the mammary gland apart from the Janus kinase 2/ signal transducer and activator of transcription 5 pathway, particularly in tumor cells. Another potential effector is activating protein-1 (AP-1), a transcription complex that regulates processes essential for neoplastic progression, including proliferation, survival and invasion. We demonstrate that PRL activates AP-1 in MCF-7 cells, detectable at 4 h and sustained for at least 24 h. Although Janus kinase 2 and ERK1/2 are the primary mediators of PRL-induced signals, c-Src, phosphatidylinositol 3'-kinase, protein kinase C, and other MAPKs contribute to maximal activity. PRL activation of these pathways leads to increased c-Jun protein and phosphorylation, JunB protein, and phosphorylation of c-Fos, elevating the levels of AP-1 complexes able to bind DNA. These active AP-1 dimers may direct expression of multiple target genes, mediating some of PRL's actions in mammary disease.
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Affiliation(s)
| | | | | | | | - LINDA A. SCHULER
- Address all correspondence and requests for reprints to: L. A. Schuler, Department of Comparative Biosciences, University of Wisconsin, 2015 Linden Drive, Madison, Wisconsin 53706. E-mail:
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Bolander FF. The mechanisms by which nitric oxide affects mammary epithelial growth and differentiation. Biochem Biophys Res Commun 2003; 304:425-30. [PMID: 12711333 DOI: 10.1016/s0006-291x(03)00598-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Nitric oxide (NO) enhances prolactin-stimulated DNA synthesis and inhibits prolactin-induced differentiation in mouse mammary epithelium. The molecular pathways used by NO were determined by employing specific inhibitors of the transducers utilized by NO. Inhibitors of the Jun N-terminal kinase (JNK) blocked the effect of NO on DNA synthesis, although this appeared to involve a protein kinase G (PKG)-independent pathway. In contrast, inhibitors of the extracellular signal-regulated kinase (ERK) prevented NO from suppressing alpha-lactalbumin accumulation and this effect was PKG-dependent. NO can also elevate cAMP through the inhibition of phosphodiesterase 3 and cAMP mimicks the actions of NO on both DNA synthesis and differentiation. However, suppression of cAMP levels did not prevent the effects of NO. Therefore, NO uses two separate pathways to affect mammary epithelium: it stimulates growth via JNK and inhibits differentiation through ERK.
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Affiliation(s)
- Franklyn F Bolander
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
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Abstract
The contribution of prolactin (PRL) to the pathogenesis and progression of human breast cancer at the cellular, transgenic, and epidemiological levels is increasingly appreciated. Acting at the endocrine and autocrine/paracrine levels, PRL functions to stimulate the growth and motility of human breast cancer cells. The actions of this ligand are mediated by at least six recognized PRL receptor isoforms found on, or secreted by, human breast epithelium. The PRL/PRL receptor complex associates with and activates several signaling networks that are shared with other members of the cytokine receptor superfamily. Coupled with the recently identified intranuclear function of PRL, these networks are integrated into the in vitro and in vivo actions induced by ligand. These findings indicate that antagonists of PRL/PRL receptor interaction or PRL receptor-associated signal transduction may be of considerable utility in the treatment of human breast cancer.
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Key Words
- cis, cytokine-inducible inhibitor of signaling
- cypb, cyclophilin b
- ecd, extracellular domain
- egf, epidermal growth factor
- ghr, gh receptor
- hprlr, human prlr
- icd, intracellular domain
- jak, janus kinase 2
- jnk, c-jun n-terminal kinase
- pias, peptide inhibitor of activated stat
- pi3k, phosphatidylinositol 3′-kinase
- prl, prolactin
- ptdins, phosphatidylinositol
- prlbp, prl binding protein
- prlr, prl receptor
- shp-2, sh2-containing protein tyrosine phosphatase
- socs, suppressor of cytokine signaling
- stat, signal transducer and activator of transcription
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Affiliation(s)
- Charles V Clevenger
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
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Lennmyr F, Karlsson S, Gerwins P, Ata KA, Terént A. Activation of mitogen-activated protein kinases in experimental cerebral ischemia. Acta Neurol Scand 2002; 106:333-40. [PMID: 12460137 DOI: 10.1034/j.1600-0404.2002.01313.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVES Mitogen-activated protein kinases (MAPK) regulate cell survival and differentiation. The aim of the present study is to investigate the activation pattern of different MAPKs [extracellular signal-regulated kinase (ERK), c-jun-N-terminal kinase (JNK) and p38] after cerebral ischemia. MATERIAL AND METHODS Rats were subjected to cerebral ischemia using a model for transient (2 h) and permanent middle cerebral artery occlusion (MCAO). The rats were allowed 6 h to 1 week of survival before immunohistochemical evaluation with phospho-specific antibodies, recognizing activated MAPKs. RESULTS ERK was activated in ipsilateral blood vessels, neurons and glia, but also in contralateral vessels. JNK activation was absent in neurons but appeared in arterial blood vessels and glia at the lesion side. Active p38 was observed in macrophages in maturing infarcts. CONCLUSIONS ERK and JNK may participate in the angiogenic response to cerebral ischemia. ERK, but not JNK, was activated in neurons, possibly indicating a pathophysiologic role. Active p38 might be involved in the inflammatory reaction.
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Affiliation(s)
- F Lennmyr
- Department of Medical Sciences, Uppsala University Hospital, Uppsala, Sweden.
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25
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Schuff KG, Hentges ST, Kelly MA, Binart N, Kelly PA, Iuvone PM, Asa SL, Low MJ. Lack of prolactin receptor signaling in mice results in lactotroph proliferation and prolactinomas by dopamine-dependent and -independent mechanisms. J Clin Invest 2002. [DOI: 10.1172/jci0215912] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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26
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Schuff KG, Hentges ST, Kelly MA, Binart N, Kelly PA, Iuvone PM, Asa SL, Low MJ. Lack of prolactin receptor signaling in mice results in lactotroph proliferation and prolactinomas by dopamine-dependent and -independent mechanisms. J Clin Invest 2002; 110:973-81. [PMID: 12370275 PMCID: PMC151153 DOI: 10.1172/jci15912] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Hypothalamic dopamine inhibits pituitary prolactin secretion and proliferation of prolactin-producing lactotroph cells by activating lactotroph dopamine D2 receptors (D2Rs). Conversely, prolactin (PRL) stimulates hypothalamic dopamine neurons via PRL receptors (PRLRs) in a short-loop feedback circuit. We used Drd2(-/-) and Prlr(-/-) mutant mice to bypass this feedback and investigate possible dopamine-independent effects of PRL on lactotroph function. The absence of either receptor induced hyperprolactinemia and large prolactinomas in females. Small macroadenomas developed in aged Prlr(-/-) males, but only microscopic adenomas were found in Drd2(-/-) male mice. Pharmacologic studies in Prlr(-/-) mice with D2R agonists and antagonists demonstrated a significant loss of endogenous dopamine tone, i.e., constitutive inhibitory signaling by the D2R, in the pituitary. However, Prlr(-/-) mice exhibited more profound hyperprolactinemia and larger tumors than did age-matched Drd2(-/-) mice, and there were additive effects in compound homozygous mutant male mice. In vitro, PRL treatment markedly inhibited the proliferation of wild-type female and male Drd2(-/-) lactotrophs, but had no effect on female Drd2(-/-) lactotrophs, suggesting a downregulation or desensitization of PRLR in response to chronic hyperprolactinemia. We conclude that PRL inhibits lactotrophs by two distinct mechanisms: (a) indirectly by activation of hypothalamic dopamine neurons and (b) directly within the pituitary in a dopamine-independent fashion.
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Affiliation(s)
- Kathryn G Schuff
- Vollum Institute, Oregon Health & Science University, Portland, Oregon 97201, USA
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Chaturvedi LS, Koul S, Sekhon A, Bhandari A, Menon M, Koul HK. Oxalate selectively activates p38 mitogen-activated protein kinase and c-Jun N-terminal kinase signal transduction pathways in renal epithelial cells. J Biol Chem 2002; 277:13321-30. [PMID: 11823457 DOI: 10.1074/jbc.m108203200] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Oxalate, a metabolic end product, is an important factor in the pathogenesis of renal stone disease. Oxalate exposure to renal epithelial cells results in re-initiation of the DNA synthesis, altered gene expression, and apoptosis, but the signaling pathways involved in these diverse effects have not been evaluated. The effects of oxalate on mitogen- and stress-activated protein kinase signaling pathways were studied in LLC-PK1 cells. Exposure to oxalate (1 mM) rapidly stimulated robust phosphorylation and activation of p38 MAPK. Oxalate exposure also induced modest activation of JNK, as monitored by phosphorylation of c-Jun. In contrast, oxalate exposure had no effect on phosphorylation and enzyme activity of p42/44 MAPK. We also show that specific inhibition of p38 MAPK by 4(4-(fluorophenyl)-2-(4-methylsulfonylphenyl)-5-(4-pyridyl)imidazole (SB203580) or by overexpression of a kinase-dead dominant negative mutant of p38 MAPK abolishes oxalate induced re-initiation of DNA synthesis in LLC-PK1 cells. The inhibition is dose-dependent and correlates with in situ activity of native p38 MAP kinase, determined as MAPK-activated protein kinase-2 activity in cell extracts. Thus, this study not only provides the first demonstration of selective activation of p38 MAPK and JNK signaling pathways by oxalate but also suggests that p38 MAPK activity is essential for the effects of oxalate on re-initiation of DNA synthesis.
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Affiliation(s)
- Lakshmi S Chaturvedi
- Biochemistry and Molecular Biology Laboratory, Vattikuti Urology Institute, Henry Ford Health Sciences Center, One Ford Place, Detroit, MI 48202, USA
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Koul S, Chaturvedi LS, Sekhon A, Bhandari A, Menon M, Koul HK. Effects of oxalate on the re-initiation of DNA synthesis in LLC-PK1 cells do not involve p42/44 MAP kinase activation. Kidney Int 2002; 61:525-33. [PMID: 11849392 DOI: 10.1046/j.1523-1755.2002.00163.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Oxalate interaction with renal epithelial cells results in a program of events that include alterations in gene expression, re-initiation of DNA synthesis, cell growth and apoptosis. Our studies focused on understanding the mechanisms involved in the oxalate-induced re-initiation of the DNA synthesis. The effects of oxalate alone or in combination with epidermal growth factor (EGF), platelet-derived growth factor (PDGF) and insulin were investigated to determine whether oxalate utilized the p42/44 mitogen activated protein (MAP) kinase pathway, which is a common pathway used by a majority of the mitogens. METHODS LLC-PK1 cells (a renal epithelial cell line of porcine origin) were exposed to oxalate in the presence or absence of three established growth factors, EGF, insulin and PDGF, and of the transcription/translation inhibitors, actinomycin-D and cycloheximide. DNA synthesis was assessed by [3H]-thymidine incorporation. p42/44 MAP kinase activity was assessed by super-shift analysis as well as by immunocomplex kinase assay. RESULTS Exposure of growth-arrested LLC-PK1 cells to oxalate resulted in the re-initiation of the DNA synthesis was abolished by [corrected] pretreatment with transcription/translation inhibitors. Oxalate (1 mmol/L), EGF (50 ng/mL) and insulin (100 ng/mL) stimulated DNA synthesis in growth-arrested LLC-PK1 cells, while PDGF (50 ng/mL) had no effect. Effects of EGF and oxalate on DNA synthesis were additive. In contrast, oxalate and insulin had antagonistic effects on DNA synthesis. Additionally, oxalate did not activate the p42/44 MAP kinase pathway while EGF stimulated this pathway. CONCLUSIONS These findings demonstrate that oxalate does not activate the p42/44 MAP kinase pathway, and the effects of oxalate are mediated by pathways that are distinct from those of EGF, PDGF and insulin.
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Affiliation(s)
- Sweaty Koul
- Biochemistry and Molecular Biology Laboratory, Vattikuti Urology Institute, Henry Ford Health Sciences Center, Detroit, Michigan 48202, USA
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Stocco CO, Lau LF, Gibori G. A calcium/calmodulin-dependent activation of ERK1/2 mediates JunD phosphorylation and induction of nur77 and 20alpha-hsd genes by prostaglandin F2alpha in ovarian cells. J Biol Chem 2002; 277:3293-302. [PMID: 11719525 DOI: 10.1074/jbc.m110936200] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have previously demonstrated that prostaglandin F(2alpha) (PGF(2alpha)) induces a rapid and transient expression of Nur77 in luteal cells. We have shown that Nur77 plays an important role in ovarian physiology by mediating the PGF(2alpha) induction of 20alpha-HSD, a steroidogenic enzyme involved in the catabolism of progesterone. In this report we established, using luteinized granulosa cells, that PGF(2alpha) stimulates in vitro nur77 expression in a time- and dose-dependent manner. Serial 5'-deletion of the nur77 promoter revealed that the necessary and sufficient elements for PGF(2alpha) induction of Nur77 promoter activity are located between the nucleotides -86 and -33 upstream of the transcription start site, this region containing two AP1 elements. JunD binds to these AP1 sites, but its binding is not stimulated by PGF(2alpha). However, mutation of the AP1 sites as well as a dominant-negative JunD abolished nur77 induction by PGF(2alpha). PGF(2alpha) induces phosphorylation of JunD bound to the nur77 promoter. Stimulation of nur77 expression and JunD phosphorylation were prevented by inhibitors of calcium, calmodulin, or ERK1/2 kinase. PGF(2alpha)-induced ERK1/2 phosphorylation was prevented by calcium/calmodulin inhibitors. We conclude that activation of JunD through a calmodulim-dependent activation of ERK1/2 mediates nur77 induction by PGF(2alpha). Finally, we demonstrated that this molecular mechanism also mediates 20alpha-hsd induction.
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Affiliation(s)
- Carlos O Stocco
- Department of Physiology and Biophysics, University of Illinois College of Medicine, Chicago, Illinois 60612, USA
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Schroeder MD, Symowicz J, Schuler LA. PRL modulates cell cycle regulators in mammary tumor epithelial cells. Mol Endocrinol 2002; 16:45-57. [PMID: 11773438 DOI: 10.1210/mend.16.1.0762] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
PRL is essential for normal lobulo-alveolar growth of the mammary gland and may contribute to mammary cancer development or progression. However, analysis of the mechanism of action of PRL in these processes is complicated by the production of PRL within mammary epithelia. To examine PRL actions in a mammary cell-specific context, we selected MCF-7 cells that lacked endogenous PRL synthesis, using PRL stimulation of interferon-gamma-activated sequence-related PRL response elements. Derived clones exhibited a greater proliferative response to PRL than control cells. To understand the mechanism, we examined, by Western analysis, levels of proteins essential for cell cycle progression as well as phosphorylation of retinoblastoma protein. The expression of cyclin D1, a critical regulator of the G1/S transition, was significantly increased by PRL and was associated with hyperphosphorylation of retinoblastoma protein at Ser(780). Cyclin B1 was also increased by PRL. In contrast, PRL decreased the Cip/Kip family inhibitor, p21, but not p16 or p27. These studies demonstrate that PRL can stimulate the cell cycle in mammary epithelia and identify specific targets in this process. This model system will enable further molecular dissection of the pathways involved in PRL-induced proliferation, increasing our understanding of this hormone and its interactions with other factors in normal and pathogenic processes.
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Affiliation(s)
- Matthew D Schroeder
- Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin 53706, USA
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Gray CA, Bartol FF, Tarleton BJ, Wiley AA, Johnson GA, Bazer FW, Spencer TE. Developmental biology of uterine glands. Biol Reprod 2001; 65:1311-23. [PMID: 11673245 DOI: 10.1095/biolreprod65.5.1311] [Citation(s) in RCA: 318] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
All mammalian uteri contain endometrial glands that synthesize or transport and secrete substances essential for survival and development of the conceptus (embryo/fetus and associated extraembryonic membranes). In rodents, uterine secretory products of the endometrial glands are unequivocally required for establishment of uterine receptivity and conceptus implantation. Analyses of the ovine uterine gland knockout model support a primary role for endometrial glands and, by default, their secretions in peri-implantation conceptus survival and development. Uterine adenogenesis is the process whereby endometrial glands develop. In humans, this process begins in the fetus, continues postnatally, and is completed during puberty. In contrast, endometrial adenogenesis is primarily a postnatal event in sheep, pigs, and rodents. Typically, endometrial adenogenesis involves differentiation and budding of glandular epithelium from luminal epithelium, followed by invagination and extensive tubular coiling and branching morphogenesis throughout the uterine stroma to the myometrium. This process requires site-specific alterations in cell proliferation and extracellular matrix (ECM) remodeling as well as paracrine cell-cell and cell-ECM interactions that support the actions of specific hormones and growth factors. Studies of uterine development in neonatal ungulates implicate prolactin, estradiol-17 beta, and their receptors in mechanisms regulating endometrial adenogenesis. These same hormones appear to regulate endometrial gland morphogenesis in menstruating primates and humans during reconstruction of the functionalis from the basalis endometrium after menses. In sheep and pigs, extensive endometrial gland hyperplasia and hypertrophy occur during gestation, presumably to provide increasing histotrophic support for conceptus growth and development. In the rabbit, sheep, and pig, a servomechanism is proposed to regulate endometrial gland development and differentiated function during pregnancy that involves sequential actions of ovarian steroid hormones, pregnancy recognition signals, and lactogenic hormones from the pituitary or placenta. That disruption of uterine development during critical organizational periods can alter the functional capacity and embryotrophic potential of the adult uterus reinforces the importance of understanding the developmental biology of uterine glands. Unexplained high rates of peri-implantation embryonic loss in humans and livestock may reflect defects in endometrial gland morphogenesis due to genetic errors, epigenetic influences of endocrine disruptors, and pathological lesions.
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Affiliation(s)
- C A Gray
- Center for Animal Biotechnology and Genomics, Department of Animal Science, Texas A&M University, College Station, Texas 77843, USA
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Barr RK, Bogoyevitch MA. The c-Jun N-terminal protein kinase family of mitogen-activated protein kinases (JNK MAPKs). Int J Biochem Cell Biol 2001; 33:1047-63. [PMID: 11551821 DOI: 10.1016/s1357-2725(01)00093-0] [Citation(s) in RCA: 199] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The c-Jun N-terminal protein kinase mitogen-activated protein kinases (JNK MAPKs) are an evolutionarily-conserved family of serine/threonine protein kinases. First identified in 1990 when intraperitoneal injection of the protein synthesis inhibitor cycloheximide activated a 54 kDa protein kinase, the JNK MAPKs have now taken on a prominent role in signal transduction. This research has revealed a number of levels of complexity. Alternative gene splicing is now recognised to result in ten different JNK MAPK isoforms of 46-55 kDa, and these isoforms differ in their substrate affinities. Furthermore, although originally classified as stress-activated protein kinases (SAPKs), or SAPKs, the JNK MAPKs are also critical mediators of signal transduction in response to stimulation by cytokines and some growth factors. JNK MAPKs have been shown to be critical mediators in dorsal closure in developing Drosophila embryos, and targeted knockout of murine JNK MAPKs has suggested a critical involvement of these kinases in mammalian embryonic development. Recent work has also highlighted their importance in programmed cell death. Thus, the JNK MAPKs may provide a critical target for regulation in both normal and diseased states.
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Affiliation(s)
- R K Barr
- Cell Signalling Laboratory, Department of Biochemistry, University of Western Australia, 35 Stirling Highway, WA 6009, Crawley, Australia
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Li C, Cheng Y, Gutmann DA, Mangoura D. Differential localization of the neurofibromatosis 1 (NF1) gene product, neurofibromin, with the F-actin or microtubule cytoskeleton during differentiation of telencephalic neurons. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2001; 130:231-48. [PMID: 11675125 DOI: 10.1016/s0165-3806(01)00190-0] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The protein product of the neurofibromatosis 1 gene, neurofibromin, is abundantly expressed in the cerebral cortex during development, but its physiological role remains unknown. To gain insights into the functions of neurofibromin in neurons, we examined patterns of expression and subcellular localization of neurofibromin during neuronal differentiation. Western blot analysis of telencephali homogenates throughout chick embryogenesis revealed that neurofibromin expression increased during embryonic development. Further analysis showed that telencephalic neurons were also enriched in neurofibromin in culture and that a biphasic gain in expression correlated well with both phases of differentiation in culture, first with a massive outgrowth of processes and gains in neurotransmitter phenotype differentiation, and then with synapse formation. Compared to proteins associated with distinct cytoskeleton systems, the pattern of neurofibromin expression correlated closely with that of the cortical cytoskeleton protein paxillin. Moreover, analysis of immunofluorescence staining of neurofibromin showed that in the presence of a protein crosslinker which preserves both soluble and filamentous cytoskeleton proteins after extraction with Triton X-100, neurofibromin colocalized with F-actin only during the first differentiation phase. This colocalization persisted when the actin cytoskeleton was collapsed with cytochalasin D treatment. In contrast, during the second phase of differentiation neurofibromin colocalized with microtubules, but not F-actin, and the staining pattern was disrupted with nocodazole, but not cytochalasin. A constant finding under all conditions was the presence of neurofibromin in the nucleus, which supports the idea that the bipartite nuclear targeting sequence between residues 2555 and 2572 of neurofibromin may be functional. In summary, we have shown that telencephalic neurons and astroblasts are enriched in neurofibromin and that the subcellular targeting of neurofibromin toward the actin or the microtubule cytoskeleton is developmentally regulated.
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Affiliation(s)
- C Li
- Department of Pediatrics, The University of Chicago, Chicago, IL 60637, USA
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Das M, Bouchey DM, Moore MJ, Hopkins DC, Nemenoff RA, Stenmark KR. Hypoxia-induced proliferative response of vascular adventitial fibroblasts is dependent on g protein-mediated activation of mitogen-activated protein kinases. J Biol Chem 2001; 276:15631-40. [PMID: 11278727 DOI: 10.1074/jbc.m010690200] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hypoxia has been shown to act as a proliferative stimulus for adventitial fibroblasts of the pulmonary artery. The signaling pathways involved in this growth response, however, remain unclear. We tested the hypothesis that hypoxia-induced proliferation of fibroblasts would be dependent on distinct (compared with serum) activation and utilization patterns of mitogen-activated protein (MAP) kinases initiated by Galpha(i/o) proteins. We found that hypoxia stimulated increases in DNA synthesis and growth of quiescent fibroblasts in the absence of exogenous mitogens and also markedly augmented serum-stimulated growth responses. Hypoxia caused a transient activation of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK), the time course and pattern of which was somewhat similar to that induced by serum but which was of lesser magnitude. On the other hand, hypoxia-induced activation of p38 MAP kinase was biphasic, whereas serum-stimulated activation of p38 MAP kinase was transient, and the magnitude of activation was greater for hypoxia compared with that of serum stimulation. ERK1/2, JNK1, and p38 MAP kinase but not JNK2 were necessary for hypoxia-induced proliferation because PD98059, SB202190, and JNK1 antisense oligonucleotides nearly ablated the growth response. JNK2 appeared to act as a negative modulator of hypoxia-induced growth because JNK2 antisense oligonucleotides led to an increase in DNA synthesis. In serum-stimulated cells, antisense JNK1 oligonucleotides and PD98059 had inhibitory effects on proliferation, whereas SB202190 led to an increase in DNA synthesis. Pertussis toxin, which blocks Galpha(i/o)-mediated signaling, markedly attenuated hypoxia-induced DNA synthesis and activation of ERK and JNK but not p38 MAP kinase. We conclude that hypoxia itself can act as a growth promoting stimulus for subsets of bovine neonatal adventitial fibroblasts largely through Galpha(i/o)-mediated activation of a complex network of MAP kinases whose specific contributions to hypoxia-induced proliferation differ from traditional serum-induced growth signals.
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MESH Headings
- Animals
- Animals, Newborn
- Aorta, Thoracic/cytology
- Aorta, Thoracic/physiology
- Cattle
- Cell Division/drug effects
- Cell Hypoxia/physiology
- Cells, Cultured
- Culture Media, Serum-Free
- Enzyme Inhibitors/pharmacology
- Fibroblasts/cytology
- Fibroblasts/physiology
- GTP-Binding Proteins/metabolism
- Imidazoles/pharmacology
- JNK Mitogen-Activated Protein Kinases
- Kinetics
- MAP Kinase Signaling System/physiology
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3
- Mitogen-Activated Protein Kinase 8
- Mitogen-Activated Protein Kinase 9
- Mitogen-Activated Protein Kinases/antagonists & inhibitors
- Mitogen-Activated Protein Kinases/genetics
- Mitogen-Activated Protein Kinases/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/physiology
- Oligodeoxyribonucleotides, Antisense/pharmacology
- Pertussis Toxin
- Phosphorylation
- Pulmonary Artery/cytology
- Pulmonary Artery/physiology
- Pyridines/pharmacology
- Virulence Factors, Bordetella/pharmacology
- p38 Mitogen-Activated Protein Kinases
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Affiliation(s)
- M Das
- Cardiovascular Pulmonary and Developmental Lung Biology Research Labs and the Department of Renal Medicine, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA.
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Mangoura D, Pelletiere C, Leung S, Sakellaridis N, Wang DX. Prolactin concurrently activates src-PLD and JAK/Stat signaling pathways to induce proliferation while promoting differentiation in embryonic astrocytes. Int J Dev Neurosci 2000; 18:693-704. [PMID: 10978848 DOI: 10.1016/s0736-5748(00)00031-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In normal development, embryonic astrocytes progress through their cell lineage by acquiring differentiation, by apoptosis, and by proliferation. In this study, we show that embryonic astrocytes may maintain and make gains in differentiation as they simultaneously progress through one cell cycle when induced by prolactin (PRL). Prolactin induced the majority of astrocytes to incorporate bromodeoxyuridine (BrdU) with a four-fold increase over controls after 18 h of exposure. Investigating possible mitogenic signaling pathways we show for the first time that prolactin is coupled to a sustained phospholipase D (PLD) activation, with an efficacy similar to the phorbol ester and astrocytic mitogen 12-tetradecanoylphorbol-13-acetate (TPA). Both cyclosporine and suramin abolished this activation. Staurosporine and calphostin C also inhibited the PRL effect by 50%, consistent with involvement of protein kinase C-(PKC)-alpha, the major PKC isoform in astrocytes. Genistein and PP1 blocked the activation indicating additional regulation by cytosolic tyrosine kinases. This profile of PLD activation was suggestive of a PLD I isoform and a mitogenic response. Upon completion of the cell cycle, analysis of glia fibrillary acidic protein (GFAP) and vimentin abundance, and glutamine synthetase (GS) activity showed that astrocytes had gained in expression of differentiation markers. Moreover, the intensity of GFAP immunofluorescence was greater per cell, as was the length of the cell processes. In exploring the signaling for prolactin-induced differentiation we found that prolactin activated the tyrosine kinase Janus kinase (JAK) 2 and significantly stimulated tyrosine, phosphorylation of the prolactin receptor. Stat 1 and 3 were also activated presumably downstream to JAK2 activation. A rapid translocation of the cytosolic Stats over the nucleus was seen in nearly every astrocyte corresponding well with the gains in GFAP per cell. The Stats translocation did not depend on MEK-ERK inhibition by PD98059, inhibition of p38 by 1 microm SB203580, or Src kinase family inhibition by PP1. Our results demonstrate the ability of PRL to concurrently induce activation of PLD, a mitogenic signaling pathway in astrocytes, and prolonged stimulation of Stat1, compatible with the increased GFAP upregulation and cell differentiation. Considered together this data may provide an explanation on the fast gain in both numbers and differentiation in the astrocytic population during development (HD 09402, CRF).
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Affiliation(s)
- D Mangoura
- Department of Pediatrics, The University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA.
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