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Gutner UA, Shupik MA, Maloshitskaya OA, Sokolov SA, Rezvykh AP, Funikov SY, Lebedev AT, Ustyugov AA, Alessenko AV. Changes in the Metabolism of Sphingoid Bases in the Brain and Spinal Cord of Transgenic FUS(1-359) Mice, a Model of Amyotrophic Lateral Sclerosis. BIOCHEMISTRY (MOSCOW) 2019; 84:1166-1176. [PMID: 31694512 DOI: 10.1134/s0006297919100055] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The aim of this study was to evaluate changes in the content of sphingoid bases - sphingosine (SPH), sphinganine, and sphingosine-1-phosphate (SPH-1-P) - and in expression of genes encoding enzymes involved in their metabolism in the brain structures (hippocampus, cortex, and cerebellum) and spinal cord of transgenic FUS(1-359) mice. FUS(1-359) mice are characterized by motor impairments and can be used as a model of amyotrophic lateral sclerosis (ALS). Lipids from the mouse brain structures and spinal cord after 2, 3, and 4 months of disease development were analyzed by chromatography/mass spectrometry, while changes in the expression of the SPHK1, SPHK2, SGPP2, SGPL1, ASAH1, and ASAH2 genes were assayed using RNA sequencing. The levels of SPH and sphinganine (i.e., sphingoid bases with pronounced pro-apoptotic properties) were dramatically increased in the spinal cord at the terminal stage of the disease. The ratio of the anti-apoptotic SPH-1-P to SPH and sphinganine sharply reduced, indicating massive apoptosis of spinal cord cells. Significant changes in the content of SPH and SPH-1-P and in the expression of genes related to their metabolism were found at the terminal ALS stage in the spinal cord. Expression of the SGPL gene (SPH-1-P lyase) was strongly activated, while expression of the SGPP2 (SPH-1-P phosphatase) gene was reduced. Elucidation of mechanisms for the regulation of sphingolipid metabolism in ALS will help to identify molecular targets for the new-generation drugs.
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Affiliation(s)
- U A Gutner
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - M A Shupik
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - O A Maloshitskaya
- Lomonosov Moscow State University, Faculty of Chemistry, Moscow, 119999, Russia
| | - S A Sokolov
- Lomonosov Moscow State University, Faculty of Chemistry, Moscow, 119999, Russia
| | - A P Rezvykh
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991, Russia
| | - S Yu Funikov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991, Russia
| | - A T Lebedev
- Lomonosov Moscow State University, Faculty of Chemistry, Moscow, 119999, Russia
| | - A A Ustyugov
- Institute of Physiologically Active Compounds, Russian Academy of Sciences, Chernogolovka, Moscow Region, 142432, Russia
| | - A V Alessenko
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, 119991, Russia.
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Alavi Naini SM, Soussi-Yanicostas N. Heparan Sulfate as a Therapeutic Target in Tauopathies: Insights From Zebrafish. Front Cell Dev Biol 2018; 6:163. [PMID: 30619849 PMCID: PMC6306439 DOI: 10.3389/fcell.2018.00163] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 11/15/2018] [Indexed: 12/13/2022] Open
Abstract
Microtubule-associated protein tau (MAPT) hyperphosphorylation and aggregation, are two hallmarks of a family of neurodegenerative disorders collectively referred to as tauopathies. In many tauopathies, including Alzheimer's disease (AD), progressive supranuclear palsy (PSP) and Pick's disease, tau aggregates are found associated with highly sulfated polysaccharides known as heparan sulfates (HSs). In AD, amyloid beta (Aβ) peptide aggregates associated with HS are also characteristic of disease. Heparin, an HS analog, promotes misfolding, hyperphosphorylation and aggregation of tau protein in vitro. HS also provides cell surface receptors for attachment and uptake of tau seeds, enabling their propagation. These findings point to HS-tau interactions as potential therapeutic targets in tauopathies. The zebrafish genome contains genes paralogous to MAPT, genes orthologous to HS biosynthetic and chain modifier enzymes, and other genes implicated in AD. The nervous system in the zebrafish bears anatomical and chemical similarities to that in humans. These homologies, together with numerous technical advantages, make zebrafish a valuable model for investigating basic mechanisms in tauopathies and identifying therapeutic targets. Here, we comprehensively review current knowledge on the role of HSs in tau pathology and HS-targeting therapeutic approaches. We also discuss novel insights from zebrafish suggesting a role for HS 3-O-sulfated motifs in tau pathology and establishing HS antagonists as potential preventive agents or therapies for tauopathies.
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Affiliation(s)
- Seyedeh Maryam Alavi Naini
- Department of Neuroscience, Institut de Biologie Paris Seine (IBPS), INSERM, CNRS, Sorbonne Université, Paris, France
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A reflection of the lasting contributions from Dr. Robert Bittman to sterol trafficking, sphingolipid and phospholipid research. Prog Lipid Res 2015; 61:19-29. [PMID: 26584871 DOI: 10.1016/j.plipres.2015.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 10/21/2015] [Accepted: 10/28/2015] [Indexed: 10/22/2022]
Abstract
With the passing of Dr. Robert Bittman from pancreatic cancer on the 1st October 2014, the lipid research field lost one of the most influential and significant personalities. Robert Bittman's genius was in chemical design and his contribution to the lipid research field was truly immense. The reagents and chemicals he designed and synthesised allowed interrogation of the role of lipids in constituting complex biophysical membranes, sterol transfer and in cellular communication networks. Here we provide a review of these works which serve as a lasting memory to his life.
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Liu M, Idkowiak-Baldys J, Roddy PL, Baldys A, Raymond J, Clarke CJ, Hannun YA. Sustained activation of protein kinase C induces delayed phosphorylation and regulates the fate of epidermal growth factor receptor. PLoS One 2013; 8:e80721. [PMID: 24244711 PMCID: PMC3823608 DOI: 10.1371/journal.pone.0080721] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 10/04/2013] [Indexed: 01/11/2023] Open
Abstract
It is well established that acute activation of members of the protein kinase C (PKC) family induced by activation of cellular receptors can transduce extracellular stimuli to intracellular signaling. However, the functions of sustained activation of PKC are not well studied. We have previously shown that sustained activation of classical PKC isoforms over 15-60 min induced the formation of the pericentrion, a subset of recycling endosomes that are sequestered perinuclearly in a PKC- and phospholipase D (PLD)-dependent manner. In this study, we investigated the role of this process in the phosphorylation of EGFR on threonine 654 (Thr-654) and in the regulation of intracellular trafficking and fate of epidermal growth factor receptor (EGFR). Sustained stimulation of the angiotensin II receptor induced translocation of the EGFR to the pericentrion, which in turn prevents full access of EGF to the EGFR. These effects required PKC and PLD activities, and direct stimulation of PKC with phorbol esters was sufficient to reproduce these effects. Furthermore, activation of PKC induced delayed phosphorylation of EGFR on Thr-654 that coincided with the formation of the pericentrion and which was dependent on PLD and endocytosis of EGFR. Thus, Thr-654 phosphorylation required the formation of the pericentrion. On the other hand, using a T654A mutant of EGFR, we find that the phosphorylation on Thr-654 was not required for translocation of EGFR to the pericentrion but was required for protection of EGFR from degradation in response to EGF. Taken together, these results demonstrate a novel role for the pericentrion in the regulation of EGFR phosphorylation, which in turn is important for the fates of EGFR.
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Affiliation(s)
- Mengling Liu
- Department of Medicine and The Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, United States of America
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Jolanta Idkowiak-Baldys
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Patrick L. Roddy
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Aleksander Baldys
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America
- Medical and Research Services, Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina, United States of America
| | - John Raymond
- Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Christopher J. Clarke
- Department of Medicine and The Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, United States of America
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Yusuf A. Hannun
- Department of Medicine and The Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, United States of America
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America
- * E-mail:
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Targeting sphingosine kinase 1 in carcinoma cells decreases proliferation and survival by compromising PKC activity and cytokinesis. PLoS One 2012; 7:e39209. [PMID: 22761740 PMCID: PMC3382615 DOI: 10.1371/journal.pone.0039209] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 05/21/2012] [Indexed: 11/20/2022] Open
Abstract
Sphingosine kinases (SK) catalyze the phosphorylation of proapoptotic sphingosine to the prosurvival factor sphingosine 1-phosphate (S1P), thereby promoting oncogenic processes. Breast (MDA-MB-231), lung (NCI-H358), and colon (HCT 116) carcinoma cells were transduced with shRNA to downregulate SK-1 expression or treated with a pharmacologic SK-1 inhibitor. The effects of SK-1 targeting were investigated by measuring the level of intracellular sphingosine, the activity of protein kinase C (PKC) and cell cycle regulators, and the mitotic index. Functional assays included measurement of cell proliferation, colony formation, apoptosis, and cell cycle analysis. Downregulation of SK-1 or its pharmacologic inhibition increased intracellular sphingosine and decreased PKC activity as shown by reduced phosphorylation of PKC substrates. In MDA-MB-231 cells this effect was most pronounced and reduced cell proliferation and colony formation, which could be mimicked using exogenous sphingosine or the PKC inhibitor RO 31-8220. SK-1 downregulation in MDA-MB-231 cells increased the number of cells with 4N and 8N DNA content, and similar effects were observed upon treatment with sphingosine or inhibitors of SK-1 or PKC. Examination of cell cycle regulators unveiled decreased cdc2 activity and expression of Chk1, which may compromise spindle checkpoint function and cytokinesis. Indeed, SK-1 kd cells entered mitosis but failed to divide, and in the presence of taxol also failed to sustain mitotic arrest, resulting in further increased endoreduplication and apoptosis. Our findings delineate an intriguing link between SK-1, PKC and components of the cell cycle machinery, which underlines the significance of SK-1 as a target for cancer therapy.
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Shier WT. Sphingosine Analogs: an Emerging New Class of Toxins that Includes the Fumonisins. ACTA ACUST UNITED AC 2008. [DOI: 10.3109/15569549209115821] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Toyokuni T, Nisar M, Dean B, Hakomori SI. A facile and regiospecific tritiation of sphingosine: Synthesis of (2S,3R,4E)-2-amino-4-octadecene-1,3-diol-1-3H. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.2580290508] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Dyatlovitskaya EV, Kandyba AG. Role of biologically active sphingolipids in tumor growth. BIOCHEMISTRY (MOSCOW) 2006; 71:10-7. [PMID: 16457613 DOI: 10.1134/s0006297906010020] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This review highlights the literature on the effects of biologically active sphingolipids (sphingosine, ceramide, sphingomyelin, glucosylceramide, gangliosides GM1, GM2, GM3, GD3, etc.) on proliferation, apoptosis, metastases, and invasiveness of tumor cells and the putative role of sphingolipids in chemotherapy of malignant tumors.
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Affiliation(s)
- E V Dyatlovitskaya
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.
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Abstract
Sphingomyelin used to be considered only as a structural molecule of the outer leaflet of the plasma membrane of mammalian cells. However, in the last five years it has become clear that sphingomyelin is rapidly degraded and resynthesized in a pathway that could function in signal transduction. Indeed, it is now known that this pathway plays a role in signal transduction for at least one cytokine, tumour necrosis factor alpha. It seems possible that other cell surface receptors will also utilize this pathway for signalling.
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Affiliation(s)
- R Kolesnick
- Laboratory of Signal Transduction, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
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Jiang Q, Gu Z, Zhang G. Activation, involvement and nuclear translocation of c-Jun N-terminal protein kinase 1 and 2 in glutamate-induced apoptosis in cultured rat cortical neurons. Brain Res 2002; 956:194-201. [PMID: 12445686 DOI: 10.1016/s0006-8993(02)03435-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Previous studies showed that c-Jun N-terminal protein kinase 1 and 2 (JNK1&2) were activated in some cases of excitotoxicity. In the present study, activation, subcellular distribution, involvement and upstream regulation of JNK1&2 were investigated in glutamate-induced excitotoxicity in cultured rat cortical neurons. As indicated by Western immunoblot from whole cellular extracts, while JNK1&2 were not significantly changed, the activated JNK1&2 (diphosphorylated JNK1&2, p-JNK1&2), were rapidly increased at 15 min exposure to 50 microM glutamate and reverted to basal level at 12 h after exposure, followed by a significant increase of apoptotic-like cell death as detected by DAPI (a fluorescent DNA binding dye) staining at 9-18 h after exposure. Blockage of the increase of p-JNK1&2 with JNK1&2 antisense oligodeoxynucleotides significantly prevented the cell death. The increase of p-JNK1&2 was largely prevented by blockage of NMDA receptor (a subtype of glutamate receptor) or protein kinase C (PKC), and each blockage also largely prevented the cell death. Combined blockage of PKC and JNK1&2 had no additive protective effect against cell death. Immunocytochemistry study showed at 15 min of glutamate exposure a whole cellular but mainly nuclear increase of p-JNK1&2, together with mild plasma decrease but large nuclear increase of JNK1&2, all of which were also largely prevented by blockage of NMDA receptor or PKC. These results suggested that mainly downstream of NMDA receptor-PKC pathway JNK1&2 were activated, nuclear translocated and causally involved in the glutamate-induced excitotoxicity, possibly through a nuclear elevation of p-JNK1&2.
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Affiliation(s)
- Qian Jiang
- Research Center for Biochemistry and Molecular Biology, Xuzhou Medical College, 84 West Huai-hai Road, Xuzhou, Jiangsu 221002, People's Republic of China
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Abstract
This review presents the structural and functional role of phospholipids in chromatin and nuclear matrix as well as the difference in composition and turnover compared to those present in the nuclear membrane. Nuclei have a very active lipid metabolism which seems to play an important role in the transduction of the signals to the genome in response to agonists acting at the plasma membrane level. The evidence on the presence of phospholipid-calcium-dependent protein kinase C (PKC) in nuclei and enzymes of phospholipids turnover is given. Protein kinase C interacts with nuclear phosphoinositol and sphingomyelin cycles products. This fact evidences about possibility that signal transduction events could also occur at the nuclear level during induction of cell proliferation, differentiation and apoptosis.
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Affiliation(s)
- A V Alessenko
- Institute of Biochemical Physics of the Russian Academy of Sciences, Kosygin str, 4, 117977, Moscow, Russia.
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Jiang Q, Gu Z, Zhang G. Nuclear translocation of extracellular signal-regulated kinases in neuronal excitotoxicity. Neuroreport 2001; 12:2417-21. [PMID: 11496121 DOI: 10.1097/00001756-200108080-00026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Subcellular distributions of extracellular signal-kinases (ERK1/2), including their activated form (p-ERK1/2), were investigated in glutamate-induced apoptotic-like death in cultured rat cortical neurons by Western immunoblot and immunocytochemistry. During 15 min glutamate exposure, p-ERK1/2 was increased in both cytosol and nuclear extracts, but prominently so in nuclear extracts. Simultaneously, ERK1/2 were mildly decreased in cytosol (to 0.7-fold vs sham control), largely increased in nuclear extracts (to 6.2-fold vs sham control), but not changed in total cell extracts. Immunocytochemistry studies also showed a large increase in nuclear and a mild decrease in cytosol extracts of ERK1/2 at 15 min of exposure. After glutamate exposure, all the above changes reverted simultaneously. The nuclear increase of ERK1/2 was largely prevented by inhibition of ERK1/2 activation, but prolonged by elongation of ERK1/2 activation. These observations suggest that stimulation of glutamate receptors in cortical neurons may incur an activation-dependent transient nuclear translocation of ERK1/2, which might be involved in excitotoxicity through a simultaneous strong elevation of p-ERK1/2 in nucleus.
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Affiliation(s)
- Q Jiang
- Research Center for Biochemistry and Molecular Biology, Xuzhou Medical College, Xuzhou 221002, PR China
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Jiang Q, Gu Z, Zhang G, Jing G. N-methyl-D-aspartate receptor activation results in regulation of extracellular signal-regulated kinases by protein kinases and phosphatases in glutamate-induced neuronal apototic-like death. Brain Res 2000; 887:285-92. [PMID: 11134617 DOI: 10.1016/s0006-8993(00)03003-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Extracellular signal-regulated kinases (ERK1/ERK2) have been shown transiently activated and involved in excitotoxicity. We searched for upstream molecules responsible for the regulation of glutamate-induced ERK1/ERK2 activation and ERK1/ERK2-mediated apototic-like death in cultured rat cortical neurons. ERK1/ERK2 activation (monitored by anti-active ERK1/ERK2 antibody) was almost completely prevented by blockage of NMDA receptor (NMDA-R) or elimination of extracellular Ca(2+), but not any other glutamate receptor or L-type voltage-gated Ca(2+) channel. It was prevented largely by inhibition of protein kinase C (PKC), protein-tyrosine kinases (PTK), respectively, but mildly by that of CaM kinase II. Combined inhibition of CaM kinase II (but not PTK) and PKC had an additive effect. Reversion of ERK1/ERK2 activation was largely prevented by inhibition of protein phosphatase (PP) 1 or protein tyrosine phosphatase (PTP). Combined inhibition of PP 1 and PTP had no additive effect. Glutamate-induced apoptotic-like death (determined by DAPI staining) was largely prevented by inhibition of NMDA-R, PKC, CaM kinase II, PTK and MEK1/MEK2 (ERK1/ERK2 kinase), respectively. Combined inhibition of CaM kinase II (but not PKC or PTK) and MEK1/MEK2 had an additive effect. Glutamate-induced apoptotic-like death was promoted by inhibition of PP1 and PTP, respectively. The above results suggested that in glutamate-induced cortical neurotoxicity ERK1/ERK2 activation be mainly mediated by NMDA-R. Subsequently, a pathway dependent on both PKC and PTK was mainly involved, which was also mainly responsible for ERK1/ERK2-mediated apoptotic-like death, and a CaM kinase II-dependent pathway was relatively mildly involved. Reversion of ERK1/ERK2 activation was mainly mediated by a pathway dependent on both PP1 and PTP, which might be involved in the restrain of glutamate-induced neurotoxicity.
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Affiliation(s)
- Q Jiang
- Research Center for Biochemistry and Molecular Biology, Xuzhou Medical College, 84 West Huai-hai Road, Xuzhou, Jiang 221002, PR China
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Carpio LC, Shiau H, Dziak R. Changes in sphingolipid levels induced by epidermal growth factor in osteoblastic cells. Effects of these metabolites on cytosolic calcium levels. Prostaglandins Leukot Essent Fatty Acids 2000; 62:225-32. [PMID: 10882186 DOI: 10.1054/plef.2000.0147] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Sphingolipids mediate a number of cellular functions in a variety of cell systems. The role they play in osteoblast signaling is yet unknown. This study investigated the effects of epidermal growth factor (EGF) on the levels of ceramide, sphingosine (SPH), and sphingosine-1-phosphate (S1P) in rat calvariae osteoblastic cells, and whether these metabolites mediated cytosolic calcium ([Ca2+]i) mobilization in these cells. EGF significantly (P<0.05) increased the levels of all three sphingolipids, and the phorbol ester PMA partially inhibited these effects. SPH and S1P markedly increased [Ca2+]i levels, with thapsigargin (depletes [Ca2+]i pools) decreasing the response by 60%. Verapamil (calcium channel blocker) only inhibited ceramide's effects on [Ca2+]i. Furthermore, SPH enhanced the EGF' induced increase in [Ca2+]i. This study demonstrates that ceramide, SPH and S1P mediate [Ca2+]i mobilization in rat calvarial osteoblastic cells, and that EGF induces changes in the levels of these metabolites with PKC playing an important role in the mechanisms regulating these events.
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Affiliation(s)
- L C Carpio
- Department of Periodontology, Harvard School of Dental Medicine, Boston, MA 02115, USA.
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Murthy S, Mathur SN, Field FJ. Tumor necrosis factor-alpha and interleukin-1beta inhibit apolipoprotein B secretion in CaCo-2 cells via the epidermal growth factor receptor signaling pathway. J Biol Chem 2000; 275:9222-9. [PMID: 10734059 DOI: 10.1074/jbc.275.13.9222] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In inflammatory conditions of the gut, cytokines are released into the mucosa and submucosa propagating and sustaining the inflammatory response. In CaCo-2 cells, we have shown that various inflammatory cytokines interfere with the secretion of lipids, an effect that is likely caused by the release of a ligand to the epidermal growth factor (EGF) receptor. In the present study, the role of the EGF receptor signaling pathway and the effects of the cytokines tumor necrosis factor-alpha (TNF-alpha) and and interleukin 1beta (IL-1beta) on triacylglycerol-rich lipoprotein secretion were investigated. CaCo-2 cells were incubated with oleic acid to enhance triacylglycerol-rich lipoprotein secretion. TNF-alpha and IL-1beta significantly decreased the basolateral secretion of apolipoprotein B (apoB) mass, with IL-1beta being more potent. Tyrphostin, an inhibitor of the EGF receptor intrinsic tryosine kinase, prevented or markedly attenuated the decrease in apoB secretion by TNF-alpha or IL-1beta. Both cytokines increased the phosphorylation of the EGF receptor by 30 min. Moreover, phosphotyrosine immunoblots of the EGF receptor demonstrated an increase in tyrosine residues phosphorylated by 0.5 and 6.5 h. At both these time points, TNF-alpha and IL-1beta also decreased the binding of EGF to its cell surface receptor. At 6.5 h, activation of the EGF receptor was sustained. In contrast, the early activation of the receptor was only transient as receptor phosphorylation and binding of EGF to its receptor returned to basal levels by 2 h. Preventing ligand binding to the EGF receptor by a receptor-blocking antibody attenuated receptor activation observed after 6.5 h. This did not occur at 0.5 h, suggesting that early activation of the EGF receptor was non-ligand-mediated. Similarly, apoB secretion was inhibited by an early non-ligand-mediated process; whereas at the later time, inhibition of apoB secretion was ligand-mediated. Thus, the inflammatory cytokines TNF-alpha and IL-1beta interfere with the secretion of triacylglycerol-rich lipoproteins by both early and delayed signaling events mediated by the EGF receptor signaling pathway.
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Affiliation(s)
- S Murthy
- Department of Internal Medicine and Veterans Affairs, University of Iowa, Iowa City, Iowa 52242, USA.
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16
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Hirose T, Terajima H, Yamauchi A, Kinoshita K, Furuke K, Gomi T, Kawai Y, Tsuyuki S, Nakamura Y, Ikai I, Taniguchi T, Inamoto T, Yamaoka Y. Oxygen dependency of epidermal growth factor receptor binding and DNA synthesis of rat hepatocytes. J Hepatol 1997; 27:1081-8. [PMID: 9453434 DOI: 10.1016/s0168-8278(97)80152-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND/AIMS Changes in oxygen availability modulate replicative responses in several cell types, but the effects on hepatocyte replication remain unclear. We have studied the effects of transient nonlethal hypoxia on epidermal growth factor receptor binding and epidermal growth factor-induced DNA synthesis of rat hepatocytes. METHODS Lactate dehydrogenase activity in culture supernatant, intracellular adenosine triphosphate content, 125I-epidermal growth factor specific binding, epidermal growth factor receptor protein expression, and 3H-thymidine incorporation were compared between hepatocytes cultured in hypoxia and normoxia. RESULTS Hypoxia up to 3 h caused no significant increase in lactate dehydrogenase activity in the culture supernatant, while intracellular adenosine triphosphate content decreased time-dependently and was restored to normoxic levels by reoxygenation (nonlethal hypoxia). Concomitantly, 125I-epidermal growth factor specific binding to hepatocytes decreased time-dependently (to 54.1% of normoxia) and was restored to control levels by reoxygenation, although 125I-insulin specific binding was not affected. The decrease in 125I-epidermal growth factor specific binding was explained by the decrease in the number of available epidermal growth factor receptors (21.37+/-3.08 to 12.16+/-1.42 fmol/10(5) cells), while the dissociation constant of the receptor was not affected. The change in the number of available receptors was not considered to be due to receptor degradation-resynthesis, since immunodetection of the epidermal growth factor receptor revealed that the receptor protein expression did not change during hypoxia and reoxygenation, and since neither actinomycin D nor cycloheximide affected the recovery of 125I-epidermal growth factor binding by reoxygenation. Inhibition of epidermal growth factor-induced DNA synthesis after hypoxia (to 75.4% of normoxia by 3 h hypoxia) paralleled the decrease in 125I-epidermal growth factor binding. CONCLUSIONS Transient hypoxia, which caused no increase in lactate dehydrogenase leakage but affected intracellular adenosine triphosphate levels, did, however, modulate the number of available epidermal growth factor receptors without affecting the receptor protein expression, and inhibit the epidermal growth factor-induced DNA synthesis of hepatocytes. This suggests that even transient nonlethal hypoxia affects the epidermal growth factor-induced DNA synthesis of rat hepatocytes through reversible changes in the epidermal growth factor receptor molecule, which depends on oxygen availability.
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Affiliation(s)
- T Hirose
- Department of Gastroenterological Surgery, Kyoto University Graduate School of Medicine, Shogoin, Sakyoku, Japan
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Riboni L, Viani P, Bassi R, Prinetti A, Tettamanti G. The role of sphingolipids in the process of signal transduction. Prog Lipid Res 1997; 36:153-95. [PMID: 9624426 DOI: 10.1016/s0163-7827(97)00008-8] [Citation(s) in RCA: 150] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- L Riboni
- Department of Medical Chemistry and Biochemistry, Medical Faculty, University of Milan, Italy
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Kim SH, Lee JY, Lee WY, Suk K. Sphingosine stimulates thrombin-induced gelation of the fibrinogen. Thromb Res 1997; 87:331-7. [PMID: 9263400 DOI: 10.1016/s0049-3848(97)00135-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- S H Kim
- Protein Function Research Unit, Korea Research Institute of Bioscience and Biotechnology, KIST, Taejon, Korea
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19
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The sphingomyelin cycle: The flip side of the lipid signaling paradigm. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s1874-5245(97)80008-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
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20
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Hakomori SI. Functional Roles of Glycosphingolipids and Sphingolipids in Signal Transduction. SPHINGOLIPID-MEDIATED SIGNAL TRANSDUCTION 1997. [DOI: 10.1007/978-3-662-22425-0_10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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21
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Abstract
Sphingolipid metabolites participate in key events of signal transduction and cell regulation. In the sphingomyelin cycle, a number of extracellular agents and insults (such as tumor necrosis factor, Fas ligands, and chemotherapeutic agents) cause the activation of sphingomyelinases, which act on membrane sphingomyelin and release ceramide. Multiple experimental approaches suggest an important role for ceramide in regulating such diverse responses as cell cycle arrest, apoptosis, and cell senescence. In vitro, ceramide activates a serine-threonine protein phosphatase, and in cells it regulates protein phosphorylation as well as multiple downstream targets [such as interleukin converting enzyme (ICE)-like proteases, stress-activated protein kinases, and the retinoblastoma gene product] that mediate its distinct cellular effects. This spectrum of inducers of ceramide accumulation and the nature of ceramide-mediated responses suggest that ceramide is a key component of intracellular stress response pathways.
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Affiliation(s)
- Y A Hannun
- The author is in the Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
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22
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Role of sphingolipid metabolites in the actions of growth factors and cytokines. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s1874-5687(96)80021-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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23
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[21] Epidermal growth factor-mediated regulation of G proteins and adenylylcyclase in cardiac muscle. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s1043-9471(96)80057-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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24
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Rigby AC, Barber KR, Grant CW. 2H-NMR study of two probe-labelled glycosphingolipid-derived signalling modulators in bilayer membranes. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1240:75-82. [PMID: 7495851 DOI: 10.1016/0005-2736(95)00156-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We describe here the first report of sphingoid bases bearing non-perturbing 2H probe nuclei. These were produced, by two different routes of partial synthesis, to permit direct assessment of their arrangement and behaviour as minor components in membrane systems. Wideline 2H-NMR spectra of N,N-dimethylsphingosine with deuterated amino-methyl groups ([2H6]dimethylsphingosine), and of lyso-dihydrogalactosylceramide (lyso-GalCer) with deuterium nuclei at C4,C5 of the sphingosine backbone and at C3,C4 of the galactose ring ([2H4]lyso-GalCer), were recorded in unsonicated, cholesterol-containing fluid bilayer membranes. The sphingolipid metabolites behaved as single populations of lipid amphiphiles dispersed uniformly in the membrane and undergoing rapid symmetric motion about their long molecular axes. This was the case throughout the pH ranges examined, which included values generally considered for the cell cytoplasm. Spectra of [2H6]dimethyl sphingosine indicated that the methyl groups are equivalent on the NMR timescale, and that the molecule's orientation and behaviour are largely unaffected by pH over the range, 6 to 10.5. There was no spectral evidence of deprotonation of the tertiary amine function in this range. Similarly, variation of pH between 6.4 and 8.9 had virtually no effect on the average conformation and orientational order of lyso-GalCer at the level of C4,C5 in the sphingosine backbone. pH did, however, exert significant control over the orientation of the galactose residue--the effect being most marked in the region of the sphingoid base pKa. The lyso-glycolipid showed some evidence of being less motionally ordered than the corresponding parent species, presumably as a result of removal of constraints imposed by the fatty acid.
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Affiliation(s)
- A C Rigby
- Department of Biochemistry, University of Western Ontario, London, Canada
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25
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López-García F, Villalaín J, Gómez-Fernández JC. Effect of sphingosine and stearylamine on the interaction of phosphatidylserine with calcium. A study using DSC, FT-IR and 45Ca(2+)-binding. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1236:279-88. [PMID: 7794967 DOI: 10.1016/0005-2736(95)00059-c] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The lamellar gel to lamellar liquid-crystalline phase transition of dipalmitoylphosphatidylserine (DPPS) multilamellar membranes is abolished by the presence of Ca2+ at DPPS/Ca2+ molar ratios of 2:1 or lower. However, when equimolar sphingosine (SPH) or stearylamine (SA), which are positively charged at the pH studied in this work, were included in DPPS vesicles, the phase transition of DPPS was still observed by differential scanning calorimetry, even in the presence of very high Ca2+ concentrations such as a DPPS/Ca2+ molar ratio of 1:10. According to that, delta H was similar for samples formed by equimolar DPPS and SPH and SA, either in the presence or in the absence of Ca2+, whereas no phase transition was observed for the pure phospholipid in the presence of Ca2+ at molar ratios lower than DPPS/Ca2+ 2:1. 45Ca(2+)-binding experiments showed that for DPPS/SPH or DPPS/SA molar ratios of 2:1, only half of the Ca2+ was bound to DPPS with respect to pure DPPS, i.e., in the absence of SPH or SA. At concentrations of SPH or SA equimolar with DPPS, the Ca2+ binding was nearly abolished. The effect of SPH and SA on the the apparent pKapp of the carboxyl group of DPPS was also studied in the presence and in the absence of Ca2+ by using Fourier transform infrared spectroscopy. The dehydration of the phosphate group of DPPS induced by the binding of Ca2+ was followed through the observation of the PO2- antisymmetric stretching, and the percentage of dehydrated PO2- groups quantitatively assayed. It was again confirmed that, in the presence of equimolar concentrations of SPH or SA, Ca2+, at concentrations which are saturating for pure DPPS, was not bound at all to DPPS. It was also found that the pKapp was considerably shifted to lower values in the presence of the amino bases, decreasing from 4.6 in pure DPPS to 2.1 and 2.2 for the equimolar mixtures of DPPS with SPH and SA, respectively. These results show that SPH and SA, being positively charged molecules anchored in the membrane, are able of preventing the binding of positively charged ions such as Ca2+ through an electrostatic charge neutralization.
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Affiliation(s)
- F López-García
- Departamento de Bioquímica y Biología Molecular A, Universidad de Murcia, Spain
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26
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Kasinathan C, William S, Vaidyanathan S, Leventhal J. Effect of lipids on glycoprotein sulphotransferase activity in rat submandibular salivary glands. Arch Oral Biol 1995; 40:433-8. [PMID: 7639646 DOI: 10.1016/0003-9969(94)00176-c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Although glycoprotein sulphation has been implicated in the processing of salivary mucin, little is known about the regulation of the enzyme responsible for this event. Using desulphated glycoprotein as sulphate acceptor, the glycoprotein sulphotransferase (GPST) from Golgi membranes of submandibular salivary gland was used to study the effect of various lipids on its activity. The GPST activity in the Golgi membrane was 0.7 pmol/mg protein per min and the activity was extractable by Triton S-100. The Km of the solubilized GPST for glycoprotein and 3'-phosphoadenosine 5'-phosphosulphate (PAPS) were 11 and 0.2 microM, respectively. Among the various lipids tested, phosphatidylinositol and sphingosine stimulated the GPST activity, while other lipids such as sphingomyelin, phosphatidylcholine and phosphatidylserine did not produce a significant effect. At 12 mol% (when expressed as mol% of sphingosine to total phospholipids plus Triton X-100) of sphingosine concentration, the enzyme activity was increased nearly 1.7-fold. The stimulatory effect of sphingosine was accompanied by a significant decrease in Km for glycoprotein from 11 to 2 microM but the increase in Vmax was small. In contrast, the sphingosine effect did not change the Km for PAPS but increased the Vmax nearly two fold. Of the two sphingosine analogues tested, threosphinganine and erythrosphinganine had a lesser stimulatory effect than sphingosine. Stearylamine was partially active, whereas the amino acids (glutamate, aspartate, glutamine, asparagine and serine) were not. These observations and our earlier finding of tyrosylprotein sulphotransferase inhibition by sphingosine demonstrate diverse sphingosine effects on the post-translational sulphation involved in the processing of salivary proteins and suggest an important role for sphingosine in the regulation of salivary protein sulphation.
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Affiliation(s)
- C Kasinathan
- Dental Research Center, New Jersey Dental School, University of Medicine and Dentistry of New Jersey, Newark 07103-2400, USA
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27
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28
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Wakita H, Tokura Y, Yagi H, Nishimura K, Furukawa F, Takigawa M. Keratinocyte differentiation is induced by cell-permeant ceramides and its proliferation is promoted by sphingosine. Arch Dermatol Res 1994; 286:350-4. [PMID: 7979551 DOI: 10.1007/bf00402228] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Ceramide and sphingosine have been suggested to be intracellular modulators of cell growth and differentiation. The effects of these sphingolipids on the growth and differentiation of keratinocytes were examined using cultured human keratinocytes (the squamous cell carcinoma cell line, DJM-1). The synthetic short-chain cell-permeant analogues of ceramides, N-acetylsphingosine, N-hexanoylsphingosine and N-octanoylsphingosine, significantly promoted differentiation as confirmed by upregulation of cornified envelope formation, synthesis of involucrin and increased transglutaminase activity, and inhibited proliferation as shown by a reduction in cell numbers, DNA amount and thymidine incorporation. Generally, these activities were greater the longer the N-acyl carbon chain. On the other hand, sphingosine at an appropriate concentration modestly stimulated the proliferation of cultured cells. Our results suggest the possibility that the growth and differentiation of keratinocytes are at least partially regulated by ceramide and sphingosine.
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Affiliation(s)
- H Wakita
- Department of Dermatology, Hamamatsu University School of Medicine, Japan
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29
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Kõiv A, Kinnunen PK. Binding of DNA to liposomes containing different derivatives of sphingosine. Chem Phys Lipids 1994; 72:77-86. [PMID: 7923481 DOI: 10.1016/0009-3084(94)90018-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Binding of DNA to dimyristoylphosphatidylcholine (DMPC) liposomes containing different sphingosine derivatives was investigated. DNA labelled with adriamycin was used as a fluorescence quencher and its membrane association was observed by resonance energy transfer from liposomes incorporating a pyrene-derivatized lipid bisPDPC as a donor and containing 19 mol% of sphingosine, dihydro-, phyto- or dimethylsphingosine. As revealed by differential scanning calorimetry, the thermal phase behaviour of multilamellar liposomes containing these sphingolipids was also significantly altered by DNA. Attachment of DNA to liposomes containing sphingosylphosphorylcholine was much weaker, and no binding of DNA to membranes containing N-acetylsphingosine, N-stearoylsphingosine or sphingomyelin was observed. The membrane binding of DNA was dependent on pH and could be reversed by the inclusion of phosphatidic acid (eggPA) into the liposomes. Analogously, the association of cytochrome c with eggPA could be reversed by the DNA-binding sphingosines. These findings lend support to our previous proposal that the DNA-sphingosine interaction is electrostatic and requires the presence of a positive charge in the latter. Accordingly, sphingosines carrying a protonated amino group attach DNA to membranes, while blocking of the amino group by N-acylation abolishes this interaction.
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Affiliation(s)
- A Kõiv
- Department of Medical Chemistry, University of Helsinki, Finland
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30
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Kothapalli R, Lui EM, Guthrie N, Chambers AF, Carroll KK. Effects of long-chain fatty amines on the growth of ras-transformed NIH 3T3 cells. Biochem Pharmacol 1994; 47:1909-16. [PMID: 8204109 DOI: 10.1016/0006-2952(94)90322-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A number of aliphatic primary amines were tested for their effects on the growth of ras-transformed NIH 3T3 cells (PAP2 cells), as measured by incorporation of tritiated thymidine into DNA. Long-chain, saturated amines (C12 to C18) were growth inhibitory, whereas short-chain amines (C6, C8) were not. Farnesylamine, a branched-chain, unsaturated amine (C15), had an IC50 of 6.9 microM compared to IC50 values of 13.1 to 45.8 microM for straight-chain, saturated amines. Oleylamine, with an IC50 of 0.1 microM, was the most potent inhibitor. The long-chain amines, but not the short-chain amines, were also effective inhibitors of protein kinase C, assayed in vitro in a cell-free system. In addition, studies with indo-1-loaded PAP2 cells showed that long-chain amines induced a reversible rise in intracellular free Ca2+ concentration. Growth inhibition by the amines was positively correlated with this effect, suggesting that factors other than protein kinase C may be involved in the inhibition of growth of PAP2 cells by long-chain amines.
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Affiliation(s)
- R Kothapalli
- Department of Biochemistry, University of Western Ontario, London, Canada
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31
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Differential effect of phosphorylation and substrate modulation on tau's ability to promote microtubule growth and nucleation. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)32639-x] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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32
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Hattori M, Kanzaki M, Kojima I, Horiuchi R. Granulosa cell luteinizing hormone receptor expression is modulated by ganglioside-specific ligands. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1221:47-53. [PMID: 8130275 DOI: 10.1016/0167-4889(94)90214-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The ganglioside GM1 (Gal beta 1-->3GalNAc beta 1-->4[NeuAc alpha 2-->3] Gal beta 1-->4Glc beta 1-->1Cer) was synthesized during granulosa cell development in vitro, and the effect of the interaction between cell-surface GM1 and its ligands on the luteinizing hormone (LH) receptor expression was investigated. GM1 synthesis, demonstrated by metabolic labeling of glycosphingolipids with [3H]galactose and binding studies using the 125I-B-subunit of cholera toxin, a specific ligand for GM1, was increased in follicle-stimulating hormone (FSH)-treated granulosa cells. When granulosa cells were cultured for 72 h in a medium containing the B-subunit of cholera toxin, FSH-induced LH-receptor contents determined by measuring the binding of 125I-deglycosylated human chorionic gonadotropin to intact cells, was augmented. The stimulatory effect of the B-subunit was dependent on the FSH concentration and culture duration. The augmentation was observed after culture for 48 h, and marked increases were evident after 72 h, which coincided with an increase of the 125I-B-subunit binding capacity. Scatchard analysis of the LH-receptor binding indicated that treatment with the B-subunit increased the number of LH-binding sites (6580 sites/cell after treatment with 20 ng/ml FSH; 11,290 sites/cell after FSH plus 100 ng/ml B-subunit), but did not alter the binding affinity. A specific antibody against GM1 mimicked the stimulatory effect of the B-subunit. The augmentation was not accompanied by granulosa cell proliferation. These findings suggest that binding of exogenous or possible endogenous ligands to cell-surface GM1 produces signals and modulates the cellular behavior during granulosa cell development.
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Affiliation(s)
- M Hattori
- Institute of Endocrinology, Gunma University, Japan
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33
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Betts J, Agranoff A, Nabel G, Shayman J. Dissociation of endogenous cellular ceramide from NF-kappa B activation. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)37215-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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34
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Reza F, Igarashi K, Tokita S, Asai K, Aoki J, Asaoka Y, Umeda M, Inoue K. Anti-idiotypic monoclonal antibody recognizes a consensus recognition site for phosphatidylserine in phosphatidylserine-specific monoclonal antibody and protein kinase C. FEBS Lett 1994; 339:229-33. [PMID: 8112460 DOI: 10.1016/0014-5793(94)80421-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In order to elucidate the molecular mechanisms responsible for the specific lipid-protein interactions, we have undertaken structural and idiotypic analyses of a monoclonal antibody, PS4A7, which binds specifically to phosphatidylserine (PS). Here we showed that one of the anti-idiotypic monoclonal antibodies raised against PS4A7 cross-reacted extensively with protein kinase C (PKC) and inhibited the activation of the enzymatic activity. The binding of the anti-idiotypic antibody to PKC was inhibited specifically by PS, but not by other phospholipids including 1,2-diacyl-sn-glycero-3-phospho-D-serine or 1,2-diacyl-sn-glycero-3-phospho-L-homoserine. In contrast, the binding of the anti-idiotypic mAb to the enzyme was significantly enhanced in the presence of either diacylglycerol or sphingosine. These findings indicate that the PS-specific monoclonal antibody and PKC share a consensus structure which is responsible for the specific interaction with PS and both diacylglycerol and sphingosine may induce a similar conformational change which exposes the PS-specific binding site of the enzyme.
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Affiliation(s)
- F Reza
- Department of Health Chemistry, Faculty of Pharmaceutical Sciences, University of Tokyo, Japan
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35
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Lavie Y, Blusztajn JK, Liscovitch M. Formation of endogenous free sphingoid bases in cells induced by changing medium conditions. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1220:323-8. [PMID: 8305506 DOI: 10.1016/0167-4889(94)90156-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Sphingoid bases are precursors and breakdown products of sphingolipids and may function as second messengers. Here we have tested the hypothesis that sphingoid bases are produced in cells in response to external stimuli. Using a high-performance liquid chromatography system, the pattern and the amounts of free sphingoid bases in various cell types (i.e., NIH-3T3, A431, NG108-15) were determined. The predominant sphingoid base in these mammalian cells was identified as C-18 sphingosine, followed by C-18 sphinganine (dihydrosphingosine). In all cells examined, the levels of endogenous sphingoid bases can be rapidly elevated by replacing cell-conditioned medium with Hepes-buffered saline or with fresh medium, causing a dramatic increase (up to 9.5-fold) in sphingosine levels within 60 min; sphinganine levels were raised to a lesser extent (up to 4.5-fold). Addition of ammonium ions inhibited the generation of sphingoid bases. These results suggest that the machinery for metabolizing sphingoid bases can be stimulated rapidly, although the exact nature of the stimulus remains obscure. Nevertheless, the ability to control sphingosine formation in cells by changing medium conditions provides a powerful tool for investigations of the physiological roles of endogenous sphingosine.
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Affiliation(s)
- Y Lavie
- Department of Hormone Research, Weizmann Institute of Science, Rehovot, Israel
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36
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Kolesnick R. Signal transduction through the sphingomyelin pathway. MOLECULAR AND CHEMICAL NEUROPATHOLOGY 1994; 21:287-97. [PMID: 8086039 DOI: 10.1007/bf02815356] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The sphingomyelin pathway is a new signal transduction system initiated by hydrolysis of plasma membrane sphingomyelin to ceramide by the actin of a neutral sphingomyelinase. Ceramide serine/threonine protein kinase termed ceramide-activated protein kinase. This kinase belongs to a family of proline-directed protein kinases that recognize substrates containing the minimal motif, X-Thr/Ser-Pro-X, where the phosphoacceptor site is followed on the carboxyl terminus by a proline residue and X may be any amino acid. Three lines of evidence, rapid kinetics of activation of the sphingomyelin pathway by tumor necrosis factor (TNF) alpha, the ability of cell-permeable ceramide analogs to bypass receptor activation and mimic the effect of TNF alpha, and reconstitution of this cascade in a cell-free system, support the concept that the sphingomyelin pathway serves to signal TNF alpha-induced monocytic differentiation. Hence, the sphingomyelin pathway may represent a signaling system analogous to more well-defined systems such as the cyclic adenosine monophosphate and phosphoinositide pathways.
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Affiliation(s)
- R Kolesnick
- Laboratory of Signal Transduction, Memorial Sloan-Kettering Cancer Center, New York, NY 10021
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37
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Schroeder J, Crane H, Xia J, Liotta D, Merrill A. Disruption of sphingolipid metabolism and stimulation of DNA synthesis by fumonisin B1. A molecular mechanism for carcinogenesis associated with Fusarium moniliforme. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)41887-4] [Citation(s) in RCA: 107] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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38
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39
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Chao C, Laulederkind S, Ballou L. Sphingosine-mediated phosphatidylinositol metabolism and calcium mobilization. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)37539-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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40
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Singh KR, Taylor LK, Campbell XZ, Fields AP, Neet KE. A bryostatin-sensitive protein kinase C required for nerve growth factor activity. Biochemistry 1994; 33:542-51. [PMID: 8286384 DOI: 10.1021/bi00168a020] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Nerve growth factor (NGF) stimulates rat pheochromocytoma cells (PC12) to differentiate into a neuronal-like cell that exhibits neurite extensions. The role of protein kinase C in signal transduction has been examined in PC12 cells treated with phorbol 12-myristate 13-acetate (PMA) and bryostatin, a macrocyclic lactone that activates protein kinase C at both the nuclear and the plasma membranes [Hocevar, B. A., & Fields, A. P. (1991) J. Biol. Chem. 266, 28-33]. In contrast to PMA down-regulation [Reinhold, D. S., & Neet, K. E. (1989) J. Biol. Chem. 264, 3538-3544], chronic (24 h) treatment with bryostatin blocked the formation of neurites in response to NGF or basic fibroblast-derived growth factor stimulation, but, like PMA, bryostatin did not block the induction of c-fos or c-jun protooncogenes by NGF. Chronic bryostatin treatment down-regulated protein kinase C activity in the cytosolic, membrane, and nuclear fractions. Acute (60 min) bryostatin or NGF treatment activated cytosolic and nuclear protein kinase C activity, suggesting possible translocation to the nucleus. Bryostatin did not induce neurite outgrowth, either alone or in combination with PMA. Thus, the bryostatin-sensitive protein kinase C is distinct from PMA- or K252a-sensitive kinases previously described. The bryostatin-sensitive protein kinase C is necessary, but not sufficient, for neurite outgrowth and acts in the nucleus in a manner independent of c-fos and c-jun transcription.
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Affiliation(s)
- K R Singh
- Department of Biological Chemistry, UHS/Chicago Medical School, Illinois 60064
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41
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Sphingosine and Other Long-Chain Bases That Alter Cell Behavior. CURRENT TOPICS IN MEMBRANES 1994. [DOI: 10.1016/s0070-2161(08)60988-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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42
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Zhou Q, Hakomori S, Kitamura K, Igarashi Y. GM3 directly inhibits tyrosine phosphorylation and de-N-acetyl-GM3 directly enhances serine phosphorylation of epidermal growth factor receptor, independently of receptor-receptor interaction. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)42121-1] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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43
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Fumonisin B1 inhibits sphingosine (sphinganine) N-acyltransferase and de novo sphingolipid biosynthesis in cultured neurons in situ. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(19)74249-5] [Citation(s) in RCA: 272] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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44
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Kõiv A, Mustonen P, Kinnunen PK. Influence of sphingosine on the thermal phase behaviour of neutral and acidic phospholipid liposomes. Chem Phys Lipids 1993; 66:123-34. [PMID: 8118913 DOI: 10.1016/0009-3084(93)90037-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The physical state of lipids is known to have pronounced effects on membrane functions. We studied the influence of sphingosine, a modulator of diverse cellular processes on the thermal phase behaviour and molecular packing of neutral and acidic phospholipids. Differential scanning calorimetry of multilamellar liposomes as well as the monolayer technique were employed. Inclusion of sphingosine in diacylphosphatidylcholine liposomes increased their pretransition temperature Tp until at about 10 mol% sphingosine this transition was abolished. For these liposomes a gradual increase in both the temperature Tm and enthalpy delta Hm of the main transition caused by sphingosine was observed. In contrast to diacylphosphatidylcholines, the Tp for dihexadecylphosphatidylcholine was lowered by sphingosine, demonstrating that the latter destabilizes the interdigitated gel phase. Inclusion of sphingosine in dimyristoylphosphatidic acid and dipalmitoylphosphatidylserine liposomes first elevated the Tm without significant changes in delta Hm, while at sphingosine contents > 50 mol% the appearance of complex melting profiles was evident. The transition temperature for the egg yolk phosphatidic acid was shifted from below 0 to 29 degrees C when mixed with sphingosine in a molar ratio of 1:1. Sphingosine also condensed the eggPA monolayers residing on an air-buffer interface. Accordingly, besides introducing a positive surface charge allowing the binding or activation of some proteins, sphingosine could influence membrane-mediated cellular processes by altering the organization and state of membrane lipids.
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Affiliation(s)
- A Kõiv
- Department of Medical Chemistry, University of Helsinki, Finland
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Kinnunen PK, Rytömaa M, Kõiv A, Lehtonen J, Mustonen P, Aro A. Sphingosine-mediated membrane association of DNA and its reversal by phosphatidic acid. Chem Phys Lipids 1993; 66:75-85. [PMID: 7509731 DOI: 10.1016/0009-3084(93)90033-y] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Resonance energy transfer was measured between egg phosphatidylcholine liposomes containing the intramolecular excimer forming pyrene-labelled phospholipid analogue 1,2-bis[pyren-1-(-yl)]decanoyl-sn-glycero-3-phosphocholine (bisPDPC) as a donor and DNA-bound adriamycin as an acceptor. Membrane association of DNA turned out to be critically dependent on the presence of sphingosine in the liposomes. Identical result was obtained by measuring the extent of quenching of the fluorescent DNA-bound dye Hoechst 33258 due to energy transfer to the lipophilic stain Nile Red incorporated in egg phosphatidylcholine liposomes containing varying amounts of sphingosine. The attachment of DNA to sphingosine-containing membranes could be reversed by the further inclusion of the negatively charged phosphatidic acid up to approximately 1:2 PA/sphingosine molar ratio in the liposomes, thus suggesting the involvement of electrostatic interactions. Differential scanning calorimetry measurements confirmed a lack of association between DNA and dimyristoylphosphatidylcholine liposomes. Instead drastic changes were produced by DNA in the heat capacity scans measured for liposomes also incorporating sphingosine. Fluorescence microscopy revealed an extensive aggregation of sphingosine containing pyrene-phosphatidylcholine-labelled egg phosphatidylcholine liposomes in the presence of DNA. Together with other available data on the effects of sphingosine, the present findings suggest that sphingosine could directly alter the chromatin structure. Accordingly, such alterations may contribute to the control of replication and gene expression.
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Affiliation(s)
- P K Kinnunen
- Department of Medical Chemistry, University of Helsinki, Finland
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Nair BG, Patel TB. Regulation of cardiac adenylyl cyclase by epidermal growth factor (EGF). Role of EGF receptor protein tyrosine kinase activity. Biochem Pharmacol 1993; 46:1239-45. [PMID: 8216375 DOI: 10.1016/0006-2952(93)90473-a] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have shown previously that the alpha subunit of the stimulatory GTP binding regulatory component of adenylyl cyclase (Gs alpha) mediates epidermal growth factor (EGF)-elicited stimulation of rat cardiac adenylyl cyclase (Nair et al., J Biol Chem 265: 21317-21322, 1990). Employing purified protein phosphotyrosine phosphatase, and benzylidene derivatives (tyrphostins: compounds 11 and 12) that selectively inhibit EGF receptor protein tyrosine kinase (EGFRK) activity, the role of EGFRK in EGF-mediated stimulation of cardiac adenylyl cyclase was investigated. The ability of the tyrphostins to inhibit the EGFRK activity in cardiac membranes was determined by monitoring tyrosine phosphorylation of either the 170 kDa protein or immunoprecipitated EGF receptor at 0 degrees and room temperature, respectively. Compounds 11 and 12, in a concentration-dependent manner, inhibited EGF receptor tyrosine kinase activity. In assays of adenylyl cyclase activity neither compound 11 nor compound 12 altered Gpp(NH)p- or isoproterenol-stimulated activity. However, both compounds, in a concentration-dependent manner, attenuated the ability of EGF to stimulate adenylyl cyclase activity without altering specific binding of [125I]EGF to cardiac membranes. Similarly, protein phosphotyrosine phosphatase obliterated the ability of EGF, but not isoproterenol, to stimulate adenylyl cyclase. Thus, we conclude that protein tyrosine kinase activity of the EGF receptor is essential for the stimulation of cardiac adenylyl cyclase by EGF.
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Affiliation(s)
- B G Nair
- Department of Pharmacology, University of Tennessee, Memphis
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The different effects of sphingosine on diacylglycerol kinase isozymes in Jurkat cells, a human T-cell line. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/0005-2760(93)90242-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Di Carlo A, Mariano A, Macchia PE, Cecere C, Ferrante G, Macchia V. Epidermal growth factor receptor and lipid membrane components in human lung cancers. J Endocrinol Invest 1993; 16:99-107. [PMID: 8463555 DOI: 10.1007/bf03347657] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The binding of 125I-epidermal growth factor (EGF) to the plasma membranes of 54 samples of human lung tumors was determined. These included 34 squamous cell carcinomas and 20 adenocarcinomas. Twenty samples of histologically normal lung excised surgically along with the tumors were used as controls. Most of the plasma membranes showed an EGF receptor level higher than that of normal tissue. A moderate increase in the amount of 125I-EGF bound (2-5 fold) was observed in the majority of the tumors. Only a few cases (5-10% of the total) showed a large increase (> than 10 fold). The binding of 125I-EGF was compared with clinical stages and grades of differentiation. No correlation between the stage of the tumor and 125I-EGF binding was observed. However, the highest levels of EGF receptor (EGF-R) were found in poorly differentiated squamous cell carcinomas. The total amount and the distribution pattern of gangliosides and phospholipids were analyzed in individual tumors. A decrease in GD1b, GD1a and sphingomyelin and an increase in GM1 and GM3 was observed. No correlation was detected when tumors with the highest or lowest levels of gangliosides or phospholipids were compared with tumors exhibiting the highest binding of 125I-EGF.
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Affiliation(s)
- A Di Carlo
- Centro di Endocrinologia ed Oncologia Sperimentale del CNR, II Facoltà di Medicina e Chirurgia, Università di Napoli, Italy
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Lister MD, Crawford-Redick CL, Loomis CR. Characterization of the neutral pH-optimum sphingomyelinase from rat brain: inhibition by copper II and ganglioside GM3. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1165:314-20. [PMID: 8418889 DOI: 10.1016/0005-2760(93)90142-v] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A neutral pH-optimum sphingomyelinase (N-SMase), solubilized from rat brain membranes, was characterized with respect to metal and membrane lipid effects. Chromatofocusing chromatography, which separates proteins according to pI, showed two N-SMase activities. One eluted at pH 4.7 and the other required 0.4 M NaCl before elution. Kinetically, the two preparations appeared similar. The N-SMase eluting at pH 4.7 was most extensively studied here. Of the phospholipids studied, only phosphatidylserine showed any influence on N-SMase and that was to increase its activity by as much as 50%. Neither serine nor phosphatidic acid had any effect. Of the cations tested, none was able to replace Mg2+ as a required activator. However, it was found that several metals were inhibitory, with Cu2+ being most effective (IC50 = 5 microM). Gangliosides, particularly the monosialoganglioside, GM3 (IC50 approximately 50 microM), inhibited N-SMase. Other glycolipids showed little effect on activity, even the immediate precursor to GM3 - lactosylceramide. The ganglioside sugar, N-acetylneuraminic acid, also had no effect on N-SMase activity. None of these inhibitors affected the acidic pH-optimum sphingomyelinase. Other sphingolipid compounds such as ceramide - the enzymatic product - and sphingosylphosphorylcholine (lysosphingomyelin) showed no capacity to inhibit N-Smase, implying that the enzyme may have a selective substrate-binding site.
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Affiliation(s)
- M D Lister
- Sphinx Pharmaceuticals Corporation, Biomolecular Research, Durham, NC 27717
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