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Kemami Wangun HV, Wood A, Fiorilla C, Reed JK, McCarthy PJ, Wright AE. Gymnochromes E and F, cytotoxic phenanthroperylenequinones from a deep-water crinoid, Holopus rangii. J Nat Prod 2010; 73:712-5. [PMID: 20158243 PMCID: PMC2859091 DOI: 10.1021/np900526y] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Bioactivity-guided fractionation of metabolites from the crinoid Holopus rangii led to the discovery of two new phenanthroperylenequinone derivatives, gymnochromes E (1) and F (2). Gymnochrome E showed cytotoxic activity toward the NCI/ADR-Res with an IC(50) of 3.5 microM. It also inhibited histone deacetylase-1 with an IC(50) of 3.3 microM. Gymnochrome F was a moderate inhibitor of myeloid cell leukemia sequence 1 (MCL-1) binding to Bak. Two anthraquinone metabolites, emodic acid (4) and its new bromo derivative (5), were also isolated from the crinoid and show remarkable similarity to the phenanthroperylenequinone core, suggesting that these metabolites share the same polyketide biosynthetic pathway.
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Affiliation(s)
- Hilaire V. Kemami Wangun
- Harbor Branch Oceanographic Institute at Florida Atlantic University, Center for Marine Biomedical and Biotechnology Research, 5600 US 1 North, Fort Pierce, FL 34946
| | - Alexander Wood
- Novartis Institutes for Biomedical Research, Cambridge, MA 02139
| | | | - John K. Reed
- Harbor Branch Oceanographic Institute at Florida Atlantic University, Center for Marine Biomedical and Biotechnology Research, 5600 US 1 North, Fort Pierce, FL 34946
| | - Peter J. McCarthy
- Harbor Branch Oceanographic Institute at Florida Atlantic University, Center for Marine Biomedical and Biotechnology Research, 5600 US 1 North, Fort Pierce, FL 34946
| | - Amy E. Wright
- Harbor Branch Oceanographic Institute at Florida Atlantic University, Center for Marine Biomedical and Biotechnology Research, 5600 US 1 North, Fort Pierce, FL 34946
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Guzmán EA, Johnson JD, Linley PA, Gunasekera SE, Wright AE. A novel activity from an old compound: Manzamine A reduces the metastatic potential of AsPC-1 pancreatic cancer cells and sensitizes them to TRAIL-induced apoptosis. Invest New Drugs 2010; 29:777-85. [PMID: 20352293 DOI: 10.1007/s10637-010-9422-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Accepted: 03/11/2010] [Indexed: 11/28/2022]
Abstract
PURPOSE Pancreatic cancer is the fourth leading cause of cancer death in the United States, and new drugs to treat the disease are needed. Pancreatic cancer cells are highly metastatic and exhibit resistance to apoptosis. Small molecules that can restore sensitivity to apoptosis or reduce metastasis would have therapeutic potential against this disease. Manzamine A is an alkaloid isolated from marine sponges that was suspected to have inhibitory activity against the mitogen activated kinase kinase (MEK). Because of this, the effects of Manzamine A were studied in pancreatic cancer cells. METHODS AsPC-1 cells were treated for 48 h in the presence of various concentrations of Manzamine A and their phenotype, cytotoxicity, cell invasion and susceptibility to apoptosis were observed. RESULTS Manzamine A decreased single cell formation, abrogated cell migration and restored the susceptibility of the cells to TRAIL-induced apoptosis in AsPC-1 cells. Its mechanism of action remains unknown, as manzamine A does not inhibit MEK. CONCLUSIONS Manzamine A appears to have a formerly unrecognized activity in blocking tumor cell invasion as well as in restoring cancer cell susceptibility to apoptosis in vitro and therefore has the potential to be used as an adjuvant to existing cancer therapies.
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Affiliation(s)
- Esther A Guzmán
- Center for Marine Biomedical and Biotechnology Research, Harbor Branch Oceanographic Institute at Florida Atlantic University, 5600 US 1 North, Ft. Pierce, FL 34946, USA.
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Paterson I, Naylor GJ, Fujita T, Guzmán E, Wright AE. Total synthesis of a library of designed hybrids of the microtubule-stabilising anticancer agents taxol, discodermolide and dictyostatin. Chem Commun (Camb) 2009; 46:261-3. [PMID: 20024345 DOI: 10.1039/b921237j] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A hybrid library of the marine natural products dictyostatin and discodermolide, incorporating the taxol or taxotere side chains, were synthesised; preliminary biological evaluation in the PANC-1 cancer cell line revealed significant antiproliferative activity, demonstrating that a macrolide scaffold is an effective surrogate for the baccatin core of taxol.
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Affiliation(s)
- Ian Paterson
- University Chemical Laboratory, Lensfield Road, Cambridge, UK, CB2 1EW.
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Abstract
Lasonolide A, a novel polyketide-derived macrolide, was previously identified from an extract of the marine sponge Forcepia sp. in an assay for protein kinase C (PKC) inhibitors. Cytotoxicity testing and profiling of lasonolide A in the National Cancer Institute (NCI) 60 cell panel screen revealed that it was potent toward a broad range of cell lines and also suggested a unique mechanism of action. Contrary to expected results, we found lasonolide A to be a strong activator of PKC in Panc-1 pancreatic carcinoma cells. Downstream mitogen-activated protein kinases, ERK 1/2 and p38 were also rapidly phosphorylated in response to lasonolide A, as was Akt. Microscopy studies revealed that lasonolide A induced blebbing and contraction of the cells within minutes of exposure, and the eventual loss of adherence. However, membrane integrity was maintained and the effects were reversible if lasonolide A was washed from the cells after their loss of adherence. Pretreatment of cells with a myosin II inhibitor, blebbistatin, slowed the early onset, but did not prevent the morphological effects of lasonolide A. Cells stained for actin filaments showed some reduction in stress fiber structure after lasonolide A exposure; however, it did not affect the polymerization of purified actin in vitro. Bisindolemaleimide, a PKC inhibitor, and wortmannin, a phosphoinositide 3-kinase; inhibitor, did not reduce lasonolide A-induced contraction or blebbing or the activation of mitogen-activated protein kinases, although Akt phosphorylation was prevented by wortmannin pretreatment. Our results indicate that lasonolide A activates multiple signal transduction pathways and suggest that the origin is upstream of PKC.
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Affiliation(s)
- Richard A Isbrucker
- Harbor Branch Oceanographic Institute at Florida Atlantic University, Center for Marine Biomedical and BiotechnologyResearch, Fort Pierce, Florida 34946, USA
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55
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Wright AE, Roth GP, Hoffman JK, Divlianska DB, Pechter D, Sennett SH, Guzmán EA, Linley P, McCarthy PJ, Pitts TP, Pomponi SA, Reed JK. Isolation, synthesis, and biological activity of aphrocallistin, an adenine-substituted bromotyramine metabolite from the Hexactinellida sponge Aphrocallistes beatrix. J Nat Prod 2009; 72:1178-1183. [PMID: 19459694 PMCID: PMC3031448 DOI: 10.1021/np900183v] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A new adenine-substituted bromotyrosine-derived metabolite designated as aphrocallistin (1) has been isolated from the deep-water Hexactinellida sponge Aphrocallistes beatrix. Its structure was elucidated on the basis of spectral data and confirmed through a convergent, modular total synthetic route that is amenable toward future analogue preparation. Aphrocallistin inhibits the growth of a panel of human tumor cell lines with IC(50) values ranging from 7.5 to >100 microM and has been shown to induce G1 cell cycle arrest in the PANC-1 pancreatic carcinoma cell line. Aphrocallistin has been fully characterized in the NCI cancer cell line panel and has undergone in vitro ADME pharmacological profiling.
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Affiliation(s)
- Amy E. Wright
- To whom correspondence should be addressed: Isolation, Tumor biology: Wright: Tel: 772-465-2400 x 459; FAX: 772-461-2221; . Synthesis, Pharmacology: Roth Tel: 407-745-2062; FAX: 407-745-2001;
| | - Gregory P. Roth
- To whom correspondence should be addressed: Isolation, Tumor biology: Wright: Tel: 772-465-2400 x 459; FAX: 772-461-2221; . Synthesis, Pharmacology: Roth Tel: 407-745-2062; FAX: 407-745-2001;
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56
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Paterson I, Gardner NM, Guzmán E, Wright AE. Total synthesis and biological evaluation of novel C2-C6 region analogues of dictyostatin. Bioorg Med Chem 2008; 17:2282-9. [PMID: 19022679 DOI: 10.1016/j.bmc.2008.10.084] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Revised: 06/12/2008] [Accepted: 10/31/2008] [Indexed: 11/26/2022]
Abstract
By exploiting a Still-Gennari HWE coupling with a common C11-C26 aldehyde, a series of C2-C6 modified analogues of the microtubule-stabilising marine natural product dictyostatin were synthesised and evaluated in vitro for growth inhibition against a range of human cancer cell lines, including the (P-glycoprotein efflux-mediated) Taxol-resistant NCI/ADR cell line. Removal of the C6 methyl substituent in dictyostatin was found to be well tolerated and led to the retention of antiproliferative activity in the low nanomolar range (IC(50)=43 nM in the NCI/ADR cell line), while partial and full saturation of the (2Z,4E)-dienoate region led to a progressive reduction in biological potency. The lactone ring size was found to be critical, as C21 to C19 translactonisation to afford 20-membered isodictyostatin analogues led to a significant loss of cytotoxicity. In a series of incubatory experiments performed on the PANC-1 cell line, all three of the 22-membered macrolide analogues acted in an analogous fashion to dictyostatin, through a mechanism of microtubule stabilization, causing both an accumulation of cells at the G2/M phase and formation of characteristic dense intracellular microtubule bundles.
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Affiliation(s)
- Ian Paterson
- University Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW, UK.
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Paterson I, Gardner NM, Guzmán E, Wright AE. Total synthesis and biological evaluation of potent analogues of dictyostatin: modification of the C2-C6 dienoate region. Bioorg Med Chem Lett 2008; 18:6268-72. [PMID: 18951787 DOI: 10.1016/j.bmcl.2008.09.109] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Accepted: 09/22/2008] [Indexed: 11/30/2022]
Abstract
By exploiting a Still-Gennari olefination of a common C11-C26 aldehyde with a C4-C10 or C1-C10 beta-ketophosphonate, three modified C2-C6 region analogues of the 22-membered macrolide dictyostatin were synthesised and evaluated in vitro for growth inhibition against a range of human cancer cell lines, including the Taxol-resistant NCI/ADR-Res cell line. 6-Desmethyldictyostatin and 2,3-dihydrodictyostatin displayed potent (low nanomolar) antiproliferative activity, intermediate between dictyostatin and discodermolide, while 2,3,4,5-tetrahydrodictyostatin showed activity comparable to discodermolide. As with dictyostatin, these simplified analogues act through a mechanism of microtubule stabilisation, G2/M arrest and apoptosis.
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Affiliation(s)
- Ian Paterson
- University Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW, UK.
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Affiliation(s)
- Lushantha S. Gunasekera
- Harbor Branch Oceanographic Institution, Inc., 5600 U.S. 1, North, Fort Pierce, Florida, 34946, USA
| | - Amy E. Wright
- Harbor Branch Oceanographic Institution, Inc., 5600 U.S. 1, North, Fort Pierce, Florida, 34946, USA
| | - Sarath P. Gunasekera
- Harbor Branch Oceanographic Institution, Inc., 5600 U.S. 1, North, Fort Pierce, Florida, 34946, USA
| | - Peter McCarthy
- Harbor Branch Oceanographic Institution, Inc., 5600 U.S. 1, North, Fort Pierce, Florida, 34946, USA
| | - John Reed
- Harbor Branch Oceanographic Institution, Inc., 5600 U.S. 1, North, Fort Pierce, Florida, 34946, USA
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Paterson I, Naylor GJ, Wright AE. Total synthesis of a potent hybrid of the anticancer natural products dictyostatin and discodermolide. Chem Commun (Camb) 2008:4628-30. [PMID: 18815706 DOI: 10.1039/b811575c] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A potent dictyostatin-discodermolide hybrid was designed and synthesised; it showed enhanced cell growth inhibitory activity relative to discodermolide in four human cancer cell lines including the Taxol-resistant NCI/ADR-Res cell line.
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Affiliation(s)
- Ian Paterson
- University Chemical Laboratory, Lensfield Road, Cambridge, UKCB2 1EW.
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60
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Cassler M, Peterson CL, Ledger A, Pomponi SA, Wright AE, Winegar R, McCarthy PJ, Lopez JV. Use of real-time qPCR to quantify members of the unculturable heterotrophic bacterial community in a deep sea marine sponge, Vetulina sp. Microb Ecol 2008; 55:384-94. [PMID: 17661179 DOI: 10.1007/s00248-007-9283-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2007] [Accepted: 06/05/2007] [Indexed: 05/16/2023]
Abstract
In this report, real-time quantitative PCR (TaqMan qPCR) of the small subunit (SSU) 16S-like rRNA molecule, a universal phylogenetic marker, was used to quantify the relative abundance of individual bacterial members of a diverse, yet mostly unculturable, microbial community from a marine sponge. Molecular phylogenetic analyses of bacterial communities derived from Caribbean Lithistid sponges have shown a wide diversity of microbes that included at least six major subdivisions; however, very little overlap was observed between the culturable and unculturable microbial communities. Based on sequence data of three culture-independent Lithistid-derived representative bacteria, we designed probe/primer sets for TaqMan qPCR to quantitatively characterize selected microbial residents in a Lithistid sponge, Vetulina, metagenome. TaqMan assays included specificity testing, DNA limit of detection analysis, and quantification of specific microbial rRNA sequences such as Nitrospira-like microbes and Actinobacteria up to 172 million copies per microgram per Lithistid sponge metagenome. By contrast, qPCR amplification with probes designed for common previously cultured sponge-associated bacteria in the genera Rheinheimera and Marinomonas and a representative of the CFB group resulted in only minimal detection of the Rheiheimera in total DNA extracted from the sponge. These data verify that a large portion of the microbial community within Lithistid sponges may consist of currently unculturable microorganisms.
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Affiliation(s)
- M Cassler
- Molecular Biology Program, MRI Florida Division, FL 32909, USA
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61
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Paterson I, Gardner NM, Poullennec KG, Wright AE. Synthesis and biological evaluation of 10,11-dihydrodictyostatin, a potent analogue of the marine anticancer agent dictyostatin. J Nat Prod 2008; 71:364-369. [PMID: 18081257 DOI: 10.1021/np070547s] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
By employing a diverted total synthesis strategy with late-stage intermediates, 10,11-dihydrodictyostatin ( 5) was prepared and evaluated in vitro for growth inhibition against a range of human cancer cell lines, including the NCI/ADR Taxol-resistant cell line. This novel dictyostatin analogue was found to retain potent antimitotic activity, with a comparable profile to discodermolide and Taxol, functioning by microtubule stabilization and G2/M arrest. These SAR studies provide further insight into the interaction between dictyostatin ( 1) and its tubulin target.
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Yang SW, Chan TM, Buevich A, Priestley T, Crona J, Reed J, Wright AE, Patel M, Gullo V, Chen G, Pramanik B, Chu M. Novel steroidal saponins, Sch 725737 and Sch 725739, from a marine starfish, Novodinia antillensis. Bioorg Med Chem Lett 2007; 17:5543-7. [PMID: 17804230 DOI: 10.1016/j.bmcl.2007.08.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Revised: 08/10/2007] [Accepted: 08/13/2007] [Indexed: 11/25/2022]
Abstract
Bioassay-guided fractionation of an active fraction from an extract of a marine starfish, Novodinia antillensis, led to the isolation and identification of two new saponins, Sch 725737 (1) and Sch 725739 (2). Compound 1 was identified as the NaV1.8 inhibitor with IC(50) of approximately 9 microM. The purification and the structure elucidation of these two saponins are described.
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Affiliation(s)
- Shu-Wei Yang
- Schering-Plough Research Institute, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA.
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63
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Wright AE, Botelho JC, Guzmán E, Harmody D, Linley P, McCarthy PJ, Pitts TP, Pomponi SA, Reed JK. Neopeltolide, a macrolide from a lithistid sponge of the family Neopeltidae. J Nat Prod 2007; 70:412-6. [PMID: 17309301 DOI: 10.1021/np060597h] [Citation(s) in RCA: 165] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A new marine-derived macrolide designated as neopeltolide (1) has been isolated from a deep-water sponge of the family Neopeltidae. Its structure was elucidated on the basis of spectroscopic data interpretation. Neopeltolide (1) is a potent inhibitor of the in vitro proliferation of the A-549 human lung adenocarcinoma, the NCI-ADR-RES human ovarian sarcoma, and the P388 murine leukemia cell lines, with IC50's of 1.2, 5.1, and 0.56 nM, respectively. Neopeltolide (1) also inhibited the growth of the fungal pathogen Candida albicans with a minimum inhibitory concentration of 0.62 microg/mL.
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Affiliation(s)
- Amy E Wright
- Center for Ocean Exploration, Biomedical Marine Research Program, Harbor Branch Oceanographic Institution, Inc., 5600 US 1 North, Ft. Pierce, FL 34946, USA.
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Paterson I, Gardner NM, Poullennec KG, Wright AE. Synthesis and biological evaluation of novel analogues of dictyostatin. Bioorg Med Chem Lett 2007; 17:2443-7. [PMID: 17336522 DOI: 10.1016/j.bmcl.2007.02.031] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Revised: 02/09/2007] [Accepted: 02/10/2007] [Indexed: 11/18/2022]
Abstract
Novel analogues of the microtubule-stabilising agent dictyostatin were designed using existing SAR information from the structurally related discodermolide, synthesised by a late-stage diversification strategy and evaluated in vitro for growth inhibition against a range of human cancer cell lines, including those known to exhibit Taxol-resistance (AsPC-1, DLD-1, PANC-1, NCI/ADR).
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Affiliation(s)
- Ian Paterson
- University Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW, UK.
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Wright AE. On the Conditions which determine the Distribution of the Coagulation following the Intra-vascular Injection of a Solution of Wooldridge's Tissue Fibrinogen: Preliminary Communication. J Physiol 2007; 12:184-91. [PMID: 16991971 PMCID: PMC1514266 DOI: 10.1113/jphysiol.1891.sp000375] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Abstract
The attention of laboratory workers is drawn to the possibility of coccidiosis as a cause of death in guinea-pigs. The purchase of a number of guinea-pigs infected with this protozoon was followed by 12 deaths when these animals were injected with material for diagnostic purposes. No deaths occurred in the laboratory stock herd, as these were kept separate from the newcomers and were not infected. The life history of the parasite is described, together with the post-mortem findings in our series of animals.
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Affiliation(s)
- P A Ellis
- Department of Pathology, the General Hospital, Newcastle upon Tyne
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67
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Park YC, Gunasekera SP, Lopez JV, McCarthy PJ, Wright AE. Metabolites from the marine-derived fungus Chromocleista sp. isolated from a deep-water sediment sample collected in the Gulf of Mexico. J Nat Prod 2006; 69:580-4. [PMID: 16643030 DOI: 10.1021/np058113p] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
As part of our ongoing chemical investigation of biologically active metabolites from marine fungi, three new compounds, p-hydroxyphenopyrrozin (1) and diketopiperazines (3, 4), have been isolated from the marine-derived fungus Chromocleista sp. In addition, the fungus gave the known compound phenopyrrozin (2), four known diketopiperazines (6-9), N-acetyltryptamine (10), and agathic acid (11). Another new diketopiperazine (5) was separated and identified as a decomposition product of 3 and 4. The structures of the new metabolites were determined on the basis of mass spectroscopy, NMR experiments, and derivatization methods. The absolute configuration of 1 was determined by X-ray crystallography studies.
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Affiliation(s)
- Young Chul Park
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, 5600 U.S. 1 North, Fort Pierce, FL 34946, USA
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Abstract
BACKGROUND following a stroke, morbidity and mortality is high, with aspiration pneumonia being a common complication. OBJECTIVES to determine the levels of colonisation by and isolation of aerobic Gram-negative bacteria (AGNB) in acute stroke patients and determine the effect of selective decontamination of the digestive tract (SDD) on oral flora and whether it reduces both morbidity and mortality after an acute stroke. DESIGN a prospective, randomised, placebo-controlled double blind trial. SETTING acute stroke assessment units of three hospitals in the northwest of England. SUBJECTS 203 patients admitted to hospital following a first acute stroke. METHODS participants were randomised to SDD oral gel or placebo. Swallow was assessed on admission to hospital, and oral swabs were obtained thrice weekly. Demographic and clinical data were recorded. RESULTS 203 patients (106 males and 97 females) participated, of whom 20 died during their hospitalisation, 19 withdrew and full follow-up was obtained for the remaining 164. A total of 122 AGNB were isolated in 105 samples from 48 patients. Abnormal swallow on admission was found in 58 patients (29%). A total of 34 patients carried a single gram-negative micro-organism that was present on one or more occasions. More than one AGNB was carried in 14 patients, and organisms were significantly more likely to be isolated from the placebo group than the active group during weeks 2 and 3 of treatment (P = 0.034, chi-squared). Seven patients in the placebo group and one in the treatment group developed pneumonia (P = 0.029, Fisher's exact test). CONCLUSIONS high carriage of and colonisation by AGNB was found within this study, which was reduced by the addition of SDD. Although SDD reduced the presence of both organisms and documented episodes of pneumonia, mortality remained unchanged.
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Affiliation(s)
- M Gosney
- The Institute of Health Sciences, Building 22, London Road, Reading RG1 5AQ, UK.
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Reddy NS, Reed JK, Longley RE, Wright AE. Two new cytotoxic linderazulenes from a deep-sea gorgonian of the genus Paramuricea. J Nat Prod 2005; 68:248-250. [PMID: 15730254 DOI: 10.1021/np040147u] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The known compound linderazulene (1) and two new linderazulenes (2, 3) were isolated from a deep-sea gorgonian Paramuricea sp. The structures of 2 and 3 were determined through spectroscopic methods. Compounds 1-3 show moderate in vitro cytotoxicity against the P388 murine leukemia cell line with IC(50)'s of 18.8, 2.7, and 15.6 microg/mL, respectively. Compound 2 showed moderate activity against the PANC-1 pancreatic cell line with an IC(50) of 18.7 microg/mL.
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Affiliation(s)
- N Srinivasa Reddy
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, 5600 US 1 North, Fort Pierce, FL 34946, USA
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Paterson I, Britton R, Delgado O, Wright AE. Stereochemical Determination of Dictyostatin, a Novel Microtubule-Stabilizing Macrolide from the Marine Sponge Corallistidae sp. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/chin.200431189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Wright AE, Chen Y, Winder PL, Pitts TP, Pomponi SA, Longley RE. Lasonolides C-g, five new lasonolide compounds from the sponge Forcepia sp. J Nat Prod 2004; 67:1351-1355. [PMID: 15332854 DOI: 10.1021/np040028e] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Five new marine-derived macrolide compounds, lasonolides C (3), D (4), E (5), F (6), and G (7), have been isolated from the sponge Forcepia sp. along with the parent compound in the series, lasonolide A (1). Their structures were elucidated on the basis of spectral data. Compounds 3-5 inhibit the in vitro proliferation of A-549 human lung adenocarcinoma cells with IC50's of 0.13, 4.5, and 0.31 microM, respectively. Compounds 3-6 inhibit the in vitro proliferation of PANC-1 human pancreatic carcinoma cells with IC50's of 0.38, 4.89, 0.57, and 15.6 microM, respectively. Compound 3 inhibits the in vitro proliferation of the NCI-ADR-RES cell line with an IC50 of 1.12 microM.
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Affiliation(s)
- Amy E Wright
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, Inc., 5600 US 1 North, Ft. Pierce, Florida 34946, USA.
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Gunasekera SP, Mickel SJ, Daeffler R, Niederer D, Wright AE, Linley P, Pitts T. Synthetic analogues of the microtubule-stabilizing agent (+)-discodermolide: preparation and biological activity. J Nat Prod 2004; 67:749-756. [PMID: 15165132 DOI: 10.1021/np030493w] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A series of seven synthetic discodermolide analogues 2-8, which are minor side products generated during the final stages in the synthesis of (+)-discodermolide (1), have been purified and evaluated for in vitro cytotoxicity against A549, P388, MFC-7, NCI/ADR, PANC-1, and VERO cell lines. These synthetic analogues showed a significant variation of cytotoxicity and confirmed the importance of the C-7 hydroxy through C-17 hydroxy molecular fragment for potency. Specifically, these analogues suggested the relevance of the C-11 hydroxyl group, the C-13 double bond, and the C-16 (S) stereochemistry for the potency of (+)-discodermolide. The preparation, purification, structure elucidation, and biological activity of these new analogues are described.
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Affiliation(s)
- Sarath P Gunasekera
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, 5600 US 1 North, Fort Pierce, Florida 34946, USA.
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73
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Paterson I, Britton R, Delgado O, Wright AE. Stereochemical determination of dictyostatin, a novel microtubule-stabilising macrolide from the marine sponge Corallistidae sp.Electronic supplementary information (ESI) available: copies of 1D and 2D NMR spectra, tables of spectral data and calculated torsion angles. See http://www.rsc.org/suppdata/cc/b3/b316390c/. Chem Commun (Camb) 2004:632-3. [PMID: 15010754 DOI: 10.1039/b316390c] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The relative stereochemistry of the 22-membered marine macrolide dictyostatin, a Taxol-like antimitotic agent, was determined based on a combination of extensive high field NMR studies, including J-based configuration analysis, and molecular modelling.
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Affiliation(s)
- Ian Paterson
- University Chemical Laboratory, Lensfield Road, Cambridge, UK CB2 1EW.
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74
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Gunasekera SP, Isbrucker RA, Longley RE, Wright AE, Pomponi SA, Reed JK. Plakolide A, a new gamma-lactone from the marine sponge Plakortis sp. J Nat Prod 2004; 67:110-111. [PMID: 14738400 DOI: 10.1021/np030294c] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Plakolide A (1), a new alpha-exomethylene-gamma-lactone isolated from the marine sponge Plakortis sp., was found to inhibit inducible nitric oxide synthase (iNOS) activity. The isolation, structure elucidation, and biological activity of plakolide A is described.
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Affiliation(s)
- Sarath P Gunasekera
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, 5600 U.S. 1 North, Fort Pierce, FL 34946, USA.
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75
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Yang SW, Chan TM, Pomponi SA, Gonsiorek W, Chen G, Wright AE, Hipkin W, Patel M, Gullo V, Pramanik B, Zavodny P, Chu M. A new sesterterpene, Sch 599473, from a marine sponge, Ircinia sp. J Antibiot (Tokyo) 2003; 56:783-6. [PMID: 14632288 DOI: 10.7164/antibiotics.56.783] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Shu-Wei Yang
- Schering-Plough Research Institute, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA.
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76
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Gunasekera SP, Zuleta IA, Longley RE, Wright AE, Pomponi SA. Discorhabdins S, T, and U, new cytotoxic pyrroloiminoquinones from a deep-water Caribbean sponge of the genus Batzella. J Nat Prod 2003; 66:1615-1617. [PMID: 14695808 DOI: 10.1021/np030292s] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Discorhabdins S, T, and U (1-3), three new discorhabdin analogues, have been isolated from a deep-water marine sponge of the genus Batzella. These discorhabdin analogues showed in vitro cytotoxicity against PANC-1, P-388, and A-549 cell lines. The isolation and structure elucidation of discorhabdins S, T, and U are described.
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Affiliation(s)
- Sarath P Gunasekera
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, 5600 US 1 North, Fort Pierce, Florida 34946, USA.
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77
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Duckworth AR, Samples GA, Wright AE, Pomponi SA. In vitro culture of the tropical sponge Axinella corrugata (Demospongiae): effect of food cell concentration on growth, clearance rate, and biosynthesis of stevensine. Mar Biotechnol (NY) 2003; 5:519-27. [PMID: 14564533 DOI: 10.1007/s10126-002-0111-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2002] [Accepted: 02/04/2003] [Indexed: 05/10/2023]
Abstract
In vitro culture is one possible method for supplying sponge metabolites for pharmaceutical applications, but appropriate feeding regimens that maximize both growth and metabolite biosynthesis are largely unknown. According to the natural concentration (NC) of cells 1 to 50 micro m in size that are available to wild Axinella corrugata, we fed explants a multispecific diet of bacteria, microalgae, and yeast at 4 different concentrations: 1NC, 3NC, 5NC, and 5+1NC (the last consisted of 5 NC of bacteria and 1 NC of microalgae and yeast). Explants fed a 3NC diet had the best culture response, growing on average from 8.5 g to 10.3 g in 8 weeks, and showing a 110% increase in concentration (milligrams per gram of dry weight) of the antitumor compound stevensine. Stevensine production in 3NC explants, representing the total milligrams of metabolite per explant, increased by 157% over the study. Explants fed at 1NC had relatively stable weights, indicating that the diet met metabolic costs only. Explants fed at the two highest concentrations lost weight after 4 weeks, possibly because long-term high cell concentration blocked their aquiferous system, reducing their ability to feed efficiently. Stevensine production in explants fed the 1NC, 5NC, or 5+1NC diets were similar, and varied little from the initial amount. A separate experiment showed that the clearance rate for A. corrugata is similar between the examined food types and cell concentrations over 5 hours, averaging 766 ml h(-1) g DW(-1).Overall, this study demonstrates that relatively small changes in food abundance can greatly affect both sponge growth and metabolite biosynthesis. The good growth and increased production of the target metabolite stevensine for A. corrugata explants fed a 3NC diet suggests that in vitro culture is a viable method of supplying some sponge metabolites.
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Affiliation(s)
- Alan R Duckworth
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, Inc., 5600 US 1 North, Fort Pierce, FL 34946, USA.
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78
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Abstract
Dictyostatin-1 had previously been isolated from a marine sponge of the genus Spongia sp. and described as a cytotoxic agent to murine and human cancer cells, but its mechanism of activity was unknown. In a routine screening assay used to detect cytotoxic compounds of marine origin, dictyostatin-1 was identified as a highly active component in an extract from a Lithistida sponge and exploration into its pharmacology was pursued. Initial studies demonstrated that dictyostatin-1 arrested cells in the G(2)/M phase of the cell cycle. Staining of these cells with antitubulin revealed cells having multiple aster formations and microtubule matrix bundling patterns similar to that seen in cells exposed to paclitaxel. Dictyostatin-1 was able to induce the polymerization of purified bovine brain tubulin in vitro and the polymerized tubulin remained stable at cold temperatures. Dictyostatin-1 also proved to be highly potent in two paclitaxel-resistant human cancer cell lines expressing active P-glycoprotein. Together, these results indicate that dictyostatin-1 is a potent inducer of tubulin polymerization and retains activity in cells expressing the P-glycoprotein efflux pump.
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Affiliation(s)
- Richard A Isbrucker
- Harbor Branch Oceanographic Institution, Inc., Division of Biomedical Marine Research, 5600 US 1 North, Fort Pierce, FL 34946, USA
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79
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Yang SW, Buivich A, Chan TM, Smith M, Lachowicz J, Pomponi SA, Wright AE, Mierzwa R, Patel M, Gullo V, Chu M. A new sterol sulfate, Sch 572423, from a marine sponge, Topsentia sp. Bioorg Med Chem Lett 2003; 13:1791-4. [PMID: 12729666 DOI: 10.1016/s0960-894x(03)00260-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Bioassay-guided fractionation of an active fraction from a marine sponge Topsentia sp. in our marine fraction library (MFL) led to the isolation and identification of halistanol sulfate (1) and a new sterol sulfate Sch 572423 (2). Compounds 1 and 2 were identified as P2Y(12) inhibitors with IC(50) of 0.48 and 2.2 microM, respectively. The general method of purification for the MFL library and the structure elucidation of compound 2 are described.
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Affiliation(s)
- Shu-Wei Yang
- Schering-Plough Research Institute, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA.
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80
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Millns B, Gosney M, Jack CIA, Martin MV, Wright AE. Acute stroke predisposes to oral gram-negative bacilli -- a cause of aspiration pneumonia? Gerontology 2003; 49:173-6. [PMID: 12679608 DOI: 10.1159/000069171] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2002] [Accepted: 05/21/2002] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES To assess any change in the oral flora in the mouths of stroke patients during the acute and rehabilitation phases and to determine whether this is related to episodes of aspiration pneumonia and clinical outcome. MATERIALS AND METHODS This observational study was carried out in hospital wards in a University teaching hospital. The subjects were patients immediately post-stroke and during the rehabilitation period, acute admissions and a group of healthy volunteers. An assessment of dentition and swallow in the presence or absence of oral aerobic gram-negative bacilli (AGNB) was correlated. RESULTS Of the acute stroke patients 52% had an unsafe swallow. AGNB carriage was documented in 34% of the acute stroke group. Of the 11 patients who died 55% had AGNB, 73% had an unsafe swallow and 36% had a combination of both. CONCLUSION AGNB is a common finding in acute stroke patients. It is not a consequence of age or acute hospitalisation and is associated with an unsafe swallow and a higher mortality.
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Affiliation(s)
- B Millns
- Department of Dental Sciences, University of Liverpool, UK
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81
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Yang SW, Chan TM, Pomponi SA, Chen G, Wright AE, Patel M, Gullo V, Pramanik B, Chu M. A New Bicyclic Guanidine Alkaloid, Sch 575948, from a Marine Sponge, Ptilocaulis spiculifer. J Antibiot (Tokyo) 2003; 56:970-2. [PMID: 14763564 DOI: 10.7164/antibiotics.56.970] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Shu-Wei Yang
- Schering-Plough Research Institute, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA.
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82
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Chen Y, McCarthy PJ, Harmody DK, Schimoler-O'Rourke R, Chilson K, Selitrennikoff C, Pomponi SA, Wright AE. New bioactive peroxides from marine sponges of the family plakiniidae. J Nat Prod 2002; 65:1509-1512. [PMID: 12398556 DOI: 10.1021/np0200414] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In our continuing program to identify compounds with antifungal properties, the ethanol extracts of two sponges of the family Plakinidae were found to inhibit the growth of the fungal pathogens Candida albicans and Aspergillus fumigatus. From these organisms three new compounds and five known compounds have been identified. A new 1,2-dioxane ring peroxide acid, 1, has been isolated from the sponge Plakortis halichondrioides along with five known compounds. Two new 1,2-dioxolane peroxide acids, 3 and 4, have been isolated from the sponge Plakinastrella onkodes. The structures were established by interpretation of spectral data. The three new compounds exhibit moderate activity against the fungal pathogen C. albicans with MICs of 5, 1.6, and 1.6 microg/mL respectively, for 1, 3, and 4. Compound 1 also showed in vitro inhibition of the fungal pathogen A. fumigatus with an IC(90) value of 5.6 microg/mL.
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Affiliation(s)
- Ying Chen
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, Inc., 5600 US 1 North, Ft. Pierce, Florida 34946, USA
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83
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Wright AE, Forleo DA, Gunawardana GP, Gunasekera SP, Koehn FE, McConnell OJ. Antitumor tetrahydroisoquinoline alkaloids from the colonial ascidian Ecteinascidia turbinata. J Org Chem 2002. [DOI: 10.1021/jo00302a006] [Citation(s) in RCA: 208] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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85
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Wright AE, Pomponi SA, Cross SS, McCarthy P. A new bis-(indole) alkaloid from a deep-water marine sponge of the genus Spongosorites. J Org Chem 2002. [DOI: 10.1021/jo00043a045] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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86
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Lopez JV, Peterson CL, Willoughby R, Wright AE, Enright E, Zoladz S, Reed JK, Pomponi SA. Characterization of genetic markers for in vitro cell line identification of the marine sponge Axinella corrugata. J Hered 2002; 93:27-36. [PMID: 12011172 DOI: 10.1093/jhered/93.1.27] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The marine sponge Axinella corrugata is being developed as a model organism for in vitro marine invertebrate research. Molecular genetics methods such as DNA fingerprinting [amplified fragment length polymorphism (AFLP) and single-stranded conformation polymorphism (SSCP)] and single-locus DNA sequence analyses were applied to this model to meet the primary objective of identifying positive A. corrugata-specific molecular markers that will aid in verifying cell identity in vitro and distinguish sponge cells from potential microbial contaminants. The extent of intra- and interspecific variation in these markers from geographically distinct samples of A. corrugata and closely related sponge taxa was also assessed. Two novel nuclear loci along with intervening transcribed spacer (ITS) regions of nuclear rRNA were characterized, although the latter appeared to better meet primary marker criteria, such as taxonomic specificity and high frequency of detection (via polymerase chain reaction [PCR]) from different individuals (n > 40) and cell cultures. Phylogenetic and phylogeographic analyses of ITS DNA sequences helped clarify taxonomies and also suggested species boundaries between and among western Atlantic and eastern Atlantic/Indian Ocean A. corrugata and Axinellidae samples. Patterns of genetic variation have important implications for the systematics, evolution, and chemical ecology of A. corrugata and related axinellids and are discussed.
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Affiliation(s)
- J V Lopez
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, 5600 U.S. 1 North, Ft. Pierce, FL 34946, USA.
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87
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Iyaniwura TT, Wright AE, Balfour DJ. Evidence that mesoaccumbens dopamine and locomotor responses to nicotine in the rat are influenced by pretreatment dose and strain. Psychopharmacology (Berl) 2001; 158:73-9. [PMID: 11685386 DOI: 10.1007/s002130100852] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2001] [Accepted: 05/16/2001] [Indexed: 10/27/2022]
Abstract
RATIONALE Sensitisation of the mesoaccumbens dopamine response to nicotine has been implicated in the development of nicotine dependence. This study explored the doses of nicotine that elicit the response in two strains of rats that differ in their baseline levels of activity. METHODS Male Sprague-Dawley and Lister hooded rats were pretreated with daily subcutaneous injections of (-)-nicotine for 7 days at doses ranging from 0.03 mg/kg to 0.90 mg/kg. Microdialysis studies were performed on day 9 in conscious freely moving rats, placed in an activity box and challenged with 0.4 mg/kg nicotine. RESULTS The acute administration of nicotine to drug-naive rats stimulated dopamine overflow in the accumbal shell but not the core. Sprague-Dawley rats, pretreated with nicotine (0.03 mg/kg/day and 0.10 mg/kg/day) showed increased basal overflow of dopamine in the accumbal core. Pretreatment with 0.10 mg/kg/day or 0.30 mg/kg/day, but not 0.03 mg/kg/day or 0.90 mg/kg/day, also caused sensitisation of the response to a nicotine challenge on the test day. Sensitisation of the locomotor response to nicotine exhibited a simple dose-response relationship, with the largest sensitisation being observed in animals pretreated with 0.90 mg/kg/day. In Lister hooded rats, pretreatment with nicotine reduced basal dopamine overflow in the accumbal core and did not cause sensitisation to a subsequent challenge with nicotine. CONCLUSIONS Sensitisation of the mesoaccumbens dopamine response to nicotine is influenced by pre-treatment dose and the strain of rats used. It is not related directly to the expression of sensitised locomotor responses to the drug and, therefore, may be implicated in other psychopharmacological properties of the drug, including dependence.
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Affiliation(s)
- T T Iyaniwura
- Biomedical Research Centre, University of Dundee Medical School, Ninewells Hospital, Dundee DD1 9SY, UK
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88
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Killday KB, Yarwood D, Sills MA, Murphy PT, Hooper JN, Wright AE. Microxine, a new cdc2 kinase inhibitor from the Australian marine sponge Microxina species. J Nat Prod 2001; 64:525-526. [PMID: 11325241 DOI: 10.1021/np000546z] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A new purine derivative microxine (1) was isolated from the Australian marine sponge Microxina sp. The compound was isolated via reversed-phase chromatography and its structure determined spectroscopically. Microxine was found to weakly inhibit cdc2 kinase activity with an IC(50) of 13 microM.
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Affiliation(s)
- K B Killday
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, Inc., 5600 US 1 North, Ft. Pierce, Florida 34946, USA
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89
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Chen Y, Killday KB, McCarthy PJ, Schimoler R, Chilson K, Selitrennikoff C, Pomponi SA, Wright AE. Three new peroxides from the sponge Plakinastrella species. J Nat Prod 2001; 64:262-264. [PMID: 11430018 DOI: 10.1021/np000368+] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two new five-membered-ring peroxide acids, plakinic acid F (3) and epiplakinic acid F (4), and a new peroxide-lactone, plakortolide F (5), were isolated from a sponge of the genus Plakinastrella collected from Felicite Island, Seychelles. The structures were elucidated through spectral analysis. The free acids 3 and 4 exhibit moderate antifungal activity against Candida albicans with minimum inhibitory concentrations of 25 micrograms/mL (SDB) and 3.1 micrograms/mL (RPMI) for 3, and 25 micrograms/mL (SDB) and 6.25 micrograms/mL (RPMI) for 4, respectively. Both also showed moderate in vitro inhibition of Aspergillus fumigatus with IC90's of 25 micrograms/mL.
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Affiliation(s)
- Y Chen
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, Inc., 5600 US 1 North, Ft. Pierce, Florida 34946, USA
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90
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Abstract
A majority of habitual tobacco smokers find it very difficult to quit the habit because they become addicted to the nicotine present in tobacco smoke. Nicotine, like other psychostimulant drugs of abuse, increases dopamine release in the principal terminal field of the mesolimbic system, the nucleus accumbens, and there is evidence that this mediates the 'rewarding' properties of the drug, which reinforce its self-administration. This review focuses on the working hypothesis that addiction to nicotine, and other psychostimulant drugs, depends upon their ability to evoke a sustained increase in dopamine release directly into the extracellular space which lies between the cells in the nucleus accumbens where it stimulates extra-synaptic dopamine receptors. It is suggested that increased stimulation of these receptors is associated with increased incentive learning or the attribution of increased incentive salience to the cues associated with acquisition and delivery of the drug. The hypothesis proposes that these cues can become conditioned reinforcers of drug-taking behaviour. The receptors, which mediate the effects of nicotine on mesoaccumbens dopamine neurones, are desensitised by sustained exposure to nicotine at concentrations commonly found in the plasma of habitual smokers. It is proposed that, at times when the plasma nicotine concentration is sufficiently high to cause desensitisation of the receptors, tobacco smoking is maintained by the conditioned reinforcers present in the tobacco smoke. The hypothesis predicts, therefore, that conditioned reinforcement may play a more important role in the addiction to tobacco than for most other addictive behaviours. As a result, studies with nicotine have the potential to contribute to our understanding of the neurobiology of addiction which cannot easily be explored using drugs, such as cocaine and amphetamine, which invariably increase dopamine overflow in the forebrain.
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Affiliation(s)
- D J Balfour
- Department of Pharmacology and Neuroscience, University of Dundee Medical School, Ninewells Hospital, UK.
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91
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Stead P, Hiscox S, Robinson PS, Pike NB, Sidebottom PJ, Roberts AD, Taylor NL, Wright AE, Pomponi SA, Langley D. Eryloside F, a novel penasterol disaccharide possessing potent thrombin receptor antagonist activity. Bioorg Med Chem Lett 2000; 10:661-4. [PMID: 10762048 DOI: 10.1016/s0960-894x(00)00063-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report the discovery of Eryloside F, a novel disaccharide of the steroidal carboxylic acid penasterol, isolated from an extract of the marine sponge Erylus formosus. The compound is a potent thrombin receptor antagonist, and furthermore inhibits human platelet aggregation in vitro.
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Affiliation(s)
- P Stead
- Bioprocessing Unit, Glaxo-Wellcome Medicines Research Centre, Stevenage, Herts, UK.
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92
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Gunasekera SP, McCarthy PJ, Longley RE, Pomponi SA, Wright AE. Secobatzellines A and B, two new enzyme inhibitors from a deep-water Caribbean sponge of the genus Batzella. J Nat Prod 1999; 62:1208-1211. [PMID: 10479344 DOI: 10.1021/np990177a] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Secobatzelline A (1), a new batzelline natural analogue, and secobatzelline B (2), a likely artifact formed during the isolation procedure, have been isolated from a deep-water marine sponge of the genus Batzella. Secobatzellines A and B inhibited the phosphatase activity of calcineurin, and secobatzelline A inhibited the peptidase activity of CPP32. Both compounds showed in vitro cytotoxicity against P-388 and A-549 cell lines. The isolation and structure elucidation of secobatzellines A (1) and B (2) are described.
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Affiliation(s)
- S P Gunasekera
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, 5600 U.S. 1 North, Fort Pierce, Florida 34946, USA.
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93
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Gunasekera SP, McCarthy PJ, Longley RE, Pomponi SA, Wright AE, Lobkovsky E, Clardy J. Discorhabdin P, a new enzyme inhibitor from a deep-water Caribbean sponge of the genus Batzella. J Nat Prod 1999; 62:173-175. [PMID: 9917313 DOI: 10.1021/np980293y] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Discorhabdin P (1), a new discorhabdin analogue, has been isolated from a deep-water marine sponge of the genus Batzella. Discorhabdin P (1) inhibited the phosphatase activity of calcineurin and the peptidase activity of CPP32. It also showed in vitro cytotoxicity against P-388 and A-549 cell lines. The isolation and structure elucidation of discorhabdin P (1) are described.
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Affiliation(s)
- S P Gunasekera
- Division of Biomedical Marine Research, Harbor Branch Oceanographic Institution, 5600 U.S. 1 North, Fort Pierce, Florida 34946, USA.
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94
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Abstract
A redox-sensitive protein that binds to the 3' untranslated region (UTR) of manganese superoxide dismutase (MnSOD) RNA has been described previously [Fazzone, H., Wangner, A., and Clerch, L. B. (1993) J. Clin. Invest. 92, 1278-1281; Chung, D. J., and Clerch, L. B. (1997) Am. J. Physiol. 16, L714-L719]. In the present study, cross-competition gel retardation and RNase H assays were used to identify a 41-base region located 111 bases downstream of the stop codon as the 3' UTR cis element involved in protein binding. The base sequence of this region is approximately 75% conserved among the 3' UTRs of rat, mouse, cow, and human MnSOD mRNAs at approximately the same distance downstream of the stop codon. The role of this protein-binding region in RNA translation was assessed in an in vitro rabbit reticulocyte lysate system. Translation of MnSOD RNA from which the 3' UTR element was deleted decreased 60% compared with translation of MnSOD RNA containing the 3' UTR cis element. In the presence of a specific competitor oligoribonucleotide that inhibits MnSOD RNA protein-binding activity, translation of MnSOD RNA containing the 3' UTR was decreased by 65%. Thus, both the cis element and RNA protein-binding activity were required for more efficient translation of the MnSOD. An analysis of ribosomal profiles suggests the MnSOD RNA-binding protein participates in the formation of the translation initiation complex. When MnSOD RNA-binding activity was inhibited, initiation complex formation was decreased by 50%. From the data obtained in this study, we propose that the 3' UTR cis element of MnSOD through its interaction with MnSOD RNA-binding protein may function as a translational enhancer.
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Affiliation(s)
- D J Chung
- Lung Biology Laboratory, Department of Physiology and Biophysics, Georgetown University School of Medicine, Washington, D.C. 20007, USA
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95
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Mann DM, Pickering-Brown SM, Bayatti NN, Wright AE, Owen F, Iwatsubo T, Saido TC. An intronic polymorphism in the presenilin-1 gene does not influence the amount or molecular form of the amyloid beta protein deposited in Alzheimer's disease. Neurosci Lett 1997; 222:57-60. [PMID: 9121723 DOI: 10.1016/s0304-3940(97)13342-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The frequency of the allele-1 polymorphism in intron 8 of the presenilin-1 (PS-1) gene, and the proportion of individuals homozygous in this respect, was investigated in 57 patients with autopsy verified Alzheimer's disease (AD). In 33 of these patients the amount of amyloid beta protein (A beta) was compared across the three PS-1 genotype groups (1/1, 1/2, 2/2). No excess of the allele-1 was detected in these patients with confirmed AD and no variations in the extent of A beta deposition, as either A beta 40 or A beta 42, in terms of plaque number or percentage area of tissue occupied, were found. We conclude that this intronic PS-1 polymorphism does not influence the pathological phenotype of AD, at least as far as A beta deposition is concerned.
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Affiliation(s)
- D M Mann
- Department of Pathological Sciences, University of Manchester, UK
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96
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Mazur W, Ali MN, Khan MM, Dabaghi SF, DeFelice CA, Paradis P, Butler EB, Wright AE, Fajardo LF, French BA, Raizner AE. High dose rate intracoronary radiation for inhibition of neointimal formation in the stented and balloon-injured porcine models of restenosis: angiographic, morphometric, and histopathologic analyses. Int J Radiat Oncol Biol Phys 1996; 36:777-88. [PMID: 8960503 DOI: 10.1016/s0360-3016(96)00298-2] [Citation(s) in RCA: 110] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE We examined the effects of intracoronary irradiation delivered at a high dose rate on neointimal hyperplasia after injury induced by two methods: balloon overstretch injury, and stent implantation in a porcine model of coronary restenosis. METHODS AND MATERIALS In 34 Hanford miniature swine, a segment of each coronary artery was targeted for injury and treatment. The artery segments were treated with 192Ir at doses of 10 Gy over 4 min (eight animals), 15 Gy over 6 min (nine animals), 25 Gy over 10 min (nine animals) or control (simulation wire only; eight animals). The treated segments were subjected to stent implantation (left anterior descending and right coronary artery) or balloon overstretch (circumflex) injury. Twenty-eight days later, repeat coronary angiography and sacrifice were done. Quantitative coronary angiography, morphometry, and extensive histopathologic analyses were carried out in a blinded fashion. RESULTS The change in minimal lumen diameter from postinjury to presacrifice in the stent-injured left anterior descending was -0.79 +/- 0.34 (mean: +/- SD) mm in the control group, compared to -0.43 +/- 0.35 mm in the 15 Gy (p = 0.04) and -0.21 +/- 0.50 mm in the 25 Gy (p = 0.01) groups; and in the balloon-injured circumflex was -0.31 +/- 0.22 mm in the control group compared to -0.03 +/- 0.18 mm in the 10 Gy (p = 0.05) and 0.00 +/- 0.33 in the 15 Gy (p = 0.01) groups. Percent area stenosis in the left anterior descending was 36 +/- 9% in the control group compared to 18 +/- 12% in the 15 Gy (p = 0.003) and 11 +/- 11% in the 25 Gy (p < 0.001) groups; and in the circumflex was 16 +/- 10% in the control groups, compared to 5 +/- 5% in the 15 Gy (p = 0.02) and 2 +/- 2% in the 25 Gy (p = 0.009) groups. Histopathology showed a striking reduction in the amount of neointima in the irradiated arteries compared with control vessels. Other radiation effects were stromal fibrin exudate, thinning of the media, and adventitial fibrosis and leukocyte infiltration in the radiated arterial segments. CONCLUSIONS High dose rate intracoronary irradiation with 192Ir effectively inhibits intimal proliferation after stent-induced as well as balloon-overstretch injury. This shorter treatment time (4 to 10 min) may provide a clinically practical approach to the prevention of restenosis after angioplasty.
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Affiliation(s)
- W Mazur
- Department of Medicine, Baylor College of Medicine and The Methodist Hospital, Houston, TX 77030, USA
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97
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Peppard JV, Loo P, Sills MA, Munster D, Pomponi SA, Wright AE. Characterization of an interleukin 6 cytokine family antagonist protein from a marine sponge, Callyspongia sp. J Biol Chem 1996; 271:7281-4. [PMID: 8631742 DOI: 10.1074/jbc.271.13.7281] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
An inhibitor of IL-6 binding to the human hepatoma line HepG2 and myeloma cell line U266 was identified in a saline extract of the marine sponge, Callyspongia sp. Functional activity, measured through the increase in haptoglobin production by HepG2 cells stimulated with IL-6, could be strongly inhibited by the extract. Similarly, IL-6-induced production of IgM by the B cell line SKW6.4 was substantially reduced. In neither cell line was there evidence of toxicity produced by the extract. Other sponges of the Callyspongia species were found to contain analogous activity. The activity was destroyed by trypsin treatment or boiling of the extract, suggesting that the inhibition is due to a protein. When the binding of IL-6 to its receptor complex was dissected in vitro, inhibition of binding of IL-6 to soluble receptor by the extract was not detected, but binding of the IL-6-sIL-6R complex to soluble gp130 was inhibited in a dose-dependent fashion. This was borne out in cellular assays since the extract inhibited activation of HepG2 cells stimulated with oncostatin M or leukemia inhibitory factor, cytokines which also use gp130 for signal transduction. These results suggest that the Callyspongia extract contains a protein which blocks the interaction of the IL-6 family of cytokines with their signal transduction moiety, gp130. Elucidation of the structure and mode of action of such a protein would be helpful in designing gp130 antagonists to inhibit the functions of this cytokine family, overproduction of which has been associated with cancer and pathologies of autoimmune disease and AIDS.
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Affiliation(s)
- J V Peppard
- Pharmaceuticals Division, Ciba-Geigy Corporation, Summit, New Jersey 07901, USA
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98
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Clerch LB, Wright AE, Coalson JJ. Lung manganese superoxide dismutase protein expression increases in the baboon model of bronchopulmonary dysplasia and is regulated at a posttranscriptional level. Pediatr Res 1996; 39:253-8. [PMID: 8825796 DOI: 10.1203/00006450-199602000-00011] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The expression of lung manganese superoxide dismutase (MnSOD) mRNA and protein were examined in a premature baboon model of hyperoxia-induced bronchopulmonary dysplasia (BPD) and BPD superimposed with bacterial infection. When 140-d gestation baboons were delivered by hysterotomy and treated for 16 d with appropriate ventilatory and oxygen support (pro re nada controls), there was an increase in both MnSOD mRNA and protein compared with 140-d or 156-d gestation, nonventilated controls. The concentration of MnSOD protein was also elevated when the prematurely delivered baboons were ventilated with a high fraction of inspired O2 to produce a primate homolog of BPD, but there was a significant decrease in the concentration of MnSOD mRNA in BPD animals compared with pro re nada controls. In the lungs of premature baboons in which Escherichia coli infection was superimposed on hyperoxia-induced BPD, MnSOD mRNA was diminished to approximately the same extent as in BPD alone, but MnSOD protein was significantly increased compared with all other groups. Taken together these data indicate that the premature baboon is capable of mounting an antioxidant response and that increased MnSOD protein expression in BPD and BPD-infected premature baboons is regulated, at least in part, at a posttranscriptional level.
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Affiliation(s)
- L B Clerch
- Department of Pediatrics and Lung Biology Laboratory, Georgetown University Medical Center, Washington, DC 20007, USA
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99
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Lindsay M, Oliveira N, Jasinska E, Johansen C, Harrington S, Wright AE, Smith D. An outbreak of Ross River virus disease in Southwestern Australia. Emerg Infect Dis 1996; 2:117-20. [PMID: 8903211 PMCID: PMC2639827 DOI: 10.3201/eid0202.960206] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Affiliation(s)
- M Lindsay
- University of Western Australia, Queen Elizabeth II Medical Centre, Nedlands, Western Australia
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100
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Broom AK, Lindsay MD, Johansen CA, Wright AE, Mackenzie JS. Two possible mechanisms for survival and initiation of Murray Valley encephalitis virus activity in the Kimberley region of Western Australia. Am J Trop Med Hyg 1995; 53:95-9. [PMID: 7625542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Two possible mechanisms are described for the initiation of Murray Valley encephalitis (MVE) virus activity in arid, epizootic regions of tropical Australia. Virus isolations were made from mosquitoes trapped shortly after the first heavy wet season rains and flooding in the east Kimberley, which followed approximately nine months of drought. A number of isolates of MVE virus were obtained, including isolates from pools of blood-engorged Culex annulirostris mosquitoes and from a single pool of male Aedes tremulus mosquitoes. The results strongly suggested that MVE virus activity was due both to its introduction in viremic vertebrate hosts, from which first-generation mosquitoes became infected following blood meals, and also to reactivation of vertically transmitted virus from desiccation-resistant eggs of Ae. tremulus. Both mechanisms are discussed with respect to environmental conditions.
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Affiliation(s)
- A K Broom
- Department of Microbiology, University of Western Australia, Queen Elizabeth II Medical Centre, Nedlands
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