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Shimamura M, Kurashige T, Mitsutake N, Nagayama Y. Aldehyde dehydrogenase activity plays no functional role in stem cell-like properties in anaplastic thyroid cancer cell lines. Endocrine 2017; 55:934-943. [PMID: 28040834 DOI: 10.1007/s12020-016-1224-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 12/28/2016] [Indexed: 12/21/2022]
Abstract
Recent studies have revealed that aldehyde dehydrogenase (ALDH) is a candidate marker for thyroid cancer stem cells, although its activity is flexible. The goal of this study is to clarify the functional significance of ALDH enzymatic activity on thyroid cancer stem cells properties in anaplastic thyroid cancer cell lines. In vitro sphere formation assay was used to judge the stemness of 4 anaplastic thyroid cancer cell lines (FRO, ACT1, 8505C, and KTC3). Two well-known ALDH inhibitors, N,N-diethylaminobenzaldehyde (DEAB) and disulfiram (DS), were first used. DEAB (50 μM) almost completely suppressed ALDH activity without affecting cell proliferation or spherogenicity. Lack of effect of ALDH suppression on spherogenicity was confirmed using shRNA for ALDH1A3, an ALDH isozyme predominantly expressed in anaplastic thyroid cancer cell lines. In contrast, an ALDH2 inhibitor DS (1 μM) inhibited spherogenicity but did not inhibit ALDH1A3 activity. Based on the recent article from another group reporting the importance of sonic hedgehog (Shh) signaling in ALDH activity and spherogenicity in thyroid cancer, the effects of the Shh inhibitor cyclopamine were also studied. Like DS, cyclopamine (1 μM) decreased spherogenicity but not ALDH activity. Finally, exogenous expression of ALDH1A3 in otherwise ALDH- TPC1 cells (a papillary thyroid cancer cell line) revealed no effect on spherogenicity. In conclusion, we here show no functional role for ALDH activity in thyroid thyroid cancer stem cells properties. That is, ALDH activity and spherogenicity are clearly dissociable. Further understanding of thyroid cancer stem cells biology in thyroid cancers remains necessary for the future development of thyroid thyroid cancer stem cells-targeted therapies.
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Affiliation(s)
- Mika Shimamura
- Department of Molecular Medicine, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
| | - Tomomi Kurashige
- Department of Molecular Medicine, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
| | - Norisato Mitsutake
- Department of Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan
| | - Yuji Nagayama
- Department of Molecular Medicine, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki, 852-8523, Japan.
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2
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Guliy OI, Bunin VD, Larionova OS, Potemkina EG, Ignatov OV. [Determination of Microbial Susceptibility to Sulfanilamides by Electrooptic Analysis]. Antibiot Khimioter 2015; 60:14-19. [PMID: 26415378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The effect of sulfanilamides (soluble streptocid as an example) on changing of the electrophysical properties (EP) of microbial cells of Escherichia coli XL-1, BL-Ril, Pseudomonasputida C-11 and BA-11 was studied. It was shown that significant changes in the orientation spectra (OS) of the cell suspensions incubated at various concentrations of the sulfanilamide resulted in changing of the electrooptic (EO) signal of the cell suspension at the first five frequencies of the orientation electric field (10-1000 Hz) with the use of soluble streptocid in a concentration of 0.3 mcg/ml. The dynamics of the drug effect on the microbial cells demonstrated a decrease of the EO signal value 5 minutes after the exposure by -59% vs. the control (the cells not exposed to the drug). During the following exposure the EO signal value practically did not change (within 5%). The changes of the OS of the cell suspensions exposed to soluble streptocid significantly differed for the susceptible and resistant strains. Determination of the activity of sulfanilamides by electrooptic analysis of microbial cell suspensions was considered possible. Changing of the microbial suspencion OS under the effect of sulfanilamides can be used as a test on the microbial cell susceptibility to drugs.
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Clark KB, Noisakran S, Onlamoon N, Hsiao HM, Roback J, Villinger F, Ansari AA, Perng GC. Multiploid CD61+ cells are the pre-dominant cell lineage infected during acute dengue virus infection in bone marrow. PLoS One 2012; 7:e52902. [PMID: 23300812 PMCID: PMC3531377 DOI: 10.1371/journal.pone.0052902] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 11/23/2012] [Indexed: 12/30/2022] Open
Abstract
Depression of the peripheral blood platelet count during acute infection is a hallmark of dengue. This thrombocytopenia has been attributed, in part, to an insufficient level of platelet production by megakaryocytes that reside in the bone marrow (BM). Interestingly, it was observed that dengue patients experience BM suppression at the onset of fever. However, few studies focus on the interaction between dengue virus (DENV) and megakaryocytes and how this interaction can lead to a reduction in platelets. In the studies reported herein, BM cells from normal healthy rhesus monkeys (RM) and humans were utilized to identify the cell lineage(s) that were capable of supporting virus infection and replication. A number of techniques were employed in efforts to address this issue. These included the use of viral RNA quantification, nonstructural protein and infectivity assays, phenotypic studies utilizing immunohistochemical staining, anti-differentiation DEAB treatment, and electron microscopy. Cumulative results from these studies revealed that cells in the BM were indeed highly permissive for DENV infection, with human BM having higher levels of viral production compared to RM. DENV-like particles were predominantly observed in multi-nucleated cells that expressed CD61+. These data suggest that megakaryocytes are likely the predominant cell type infected by DENV in BM, which provides one explanation for the thrombocytopenia and the dysfunctional platelets characteristic of dengue virus infection.
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Affiliation(s)
- Kristina B. Clark
- Department of Pathology and Laboratory Medicine & the Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Sansanee Noisakran
- Department of Pathology and Laboratory Medicine & the Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Medical Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Bangkok, Thailand
| | - Nattawat Onlamoon
- Department of Pathology and Laboratory Medicine & the Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Hui-Mien Hsiao
- Department of Pathology and Laboratory Medicine & the Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - John Roback
- Center for Emory Bone Marrow Transplant Center, Emory University, Atlanta, Georgia, United States of America
| | - Francois Villinger
- Department of Pathology and Laboratory Medicine & the Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Division of Pathology, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, United States of America
| | - Aftab A. Ansari
- Department of Pathology and Laboratory Medicine & the Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Guey Chuen Perng
- Department of Pathology and Laboratory Medicine & the Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan
- * E-mail:
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Alexa K, Choe SK, Hirsch N, Etheridge L, Laver E, Sagerström CG. Maternal and zygotic aldh1a2 activity is required for pancreas development in zebrafish. PLoS One 2009; 4:e8261. [PMID: 20011517 PMCID: PMC2788244 DOI: 10.1371/journal.pone.0008261] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Accepted: 11/17/2009] [Indexed: 11/18/2022] Open
Abstract
We have isolated and characterized a novel zebrafish pancreas mutant. Mutant embryos lack expression of isl1 and sst in the endocrine pancreas, but retain isl1 expression in the CNS. Non-endocrine endodermal gene expression is less affected in the mutant, with varying degrees of residual expression observed for pdx1, carbA, hhex, prox1, sid4, transferrin and ifabp. In addition, mutant embryos display a swollen pericardium and lack fin buds. Genetic mapping revealed a mutation resulting in a glycine to arginine change in the catalytic domain of the aldh1a2 gene, which is required for the production of retinoic acid from vitamin A. Comparison of our mutant (aldh1a2um22) to neckless (aldh1a2i26), a previously identified aldh1a2 mutant, revealed similarities in residual endodermal gene expression. In contrast, treatment with DEAB (diethylaminobenzaldehyde), a competitive reversible inhibitor of Aldh enzymes, produces a more severe phenotype with complete loss of endodermal gene expression, indicating that a source of Aldh activity persists in both mutants. We find that mRNA from the aldh1a2um22 mutant allele is inactive, indicating that it represents a null allele. Instead, the residual Aldh activity is likely due to maternal aldh1a2, since we find that translation-blocking, but not splice-blocking, aldh1a2 morpholinos produce a phenotype similar to DEAB treatment. We conclude that Aldh1a2 is the primary Aldh acting during pancreas development and that maternal Aldh1a2 activity persists in aldh1a2um22 and aldh1a2i26 mutant embryos.
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Affiliation(s)
- Kristen Alexa
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Seong-Kyu Choe
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Nicolas Hirsch
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Letitiah Etheridge
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Elizabeth Laver
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Charles G. Sagerström
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- * E-mail:
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5
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Alsop D, Matsumoto J, Brown S, Van Der Kraak G. Retinoid requirements in the reproduction of zebrafish. Gen Comp Endocrinol 2008; 156:51-62. [PMID: 18158153 DOI: 10.1016/j.ygcen.2007.11.008] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [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: 08/09/2007] [Revised: 11/02/2007] [Accepted: 11/12/2007] [Indexed: 11/21/2022]
Abstract
This study examines whether retinoids are essential in the reproduction of zebrafish. Using RT-PCR, it was shown that the ovaries and testes express enzymes that synthesize and metabolize the hormone retinoic acid (RA) (raldh2 and cyp26a, respectively), and RA receptors (raraa, rarga, rxrba, rxrbb, rxrga but not rxrab). Three new isoforms of rxrba were also observed in a variety of tissues. In other experiments, zebrafish were exposed for 11 d to diethylaminobenzaldehyde (DEAB), an inhibitor of RA synthesis, or fed a retinoid deficient diet for 130 d in order to evaluate the functional requirements of retinoids in reproduction. DEAB altered cyp26a transcript numbers in the gonads, suggesting an impact on RA, and decreased the number of spawned eggs by 95%. The retinoid deficient diet decreased whole body retinoids (retinol and retinal) by 68% in females and 33% in males. Females fed the retinoid deficient diet also produced 73% fewer eggs that contained 78% less retinal than controls. Fertilization rates were not affected. These studies have shown that the RA receptors are expressed in zebrafish gonads, and RA is required for the spawning of eggs. Dietary retinoid content influences reproduction, while retinyl ester storage levels appear to be of little significance. Females were more susceptible to retinoid perturbation than males, likely due to the cost of retinal deposition in the eggs. Overall, these studies have shown retinoids play a fundamental role in the reproduction of zebrafish, and the lack of retinyl ester stores in controls that successfully spawned illustrates that we have only a limited understanding of the retinoid physiology and requirements of fish.
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Affiliation(s)
- Derek Alsop
- Department of Integrative Biology, University of Guelph, Guelph, Ont., Canada.
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6
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Reijntjes S, Rodaway A, Maden M. The retinoic acid metabolising gene, CYP26B1, patterns the cartilaginous cranial neural crest in zebrafish. Int J Dev Biol 2007; 51:351-60. [PMID: 17616924 DOI: 10.1387/ijdb.062258sr] [Citation(s) in RCA: 20] [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: 10/23/2022]
Abstract
We have investigated the function of the retinoic acid metabolising enzyme, CYP26B1, by administering an antisense morpholino oligonucleotide to zebrafish embryos. The result was an alteration in the morphology of the embryo in those regions which express the gene, namely an embryo with a smaller head, correspondingly smaller hindbrain rhombomeres and severely reduced numbers of vagal brachiomotor neurons. Most strikingly, these embryos had defective or absent jaw cartilages implying a role for this enzyme in patterning or migration of the neural crest cells which give rise to this tissue type. In order to determine whether this phenotype resembles that of excess retinoic acid or a deficiency of retinoic acid, we compared the jaw defects following retinoic acid treatment or DEAB treatment, the latter being an inhibitor of retinoic acid synthesis. The effects of the inhibitor rather than excess retinoic acid most closely phenocopied the jaw defects seen with the Cyp26B1 morpholino which suggests that, at least in the zebrafish embryo, the action of CYP26B1 in the neural crest may not be simply to catabolise all-trans-RA.
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Affiliation(s)
- Susan Reijntjes
- Randall Division of Cell and Molecular Biophysics, King's College London, UK
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7
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Reifenberger MS, Arnett KL, Gatto C, Milanick MA. Extracellular terbium and divalent cation effects on the red blood cell Na pump and chrysoidine effects on the renal Na pump. Blood Cells Mol Dis 2007; 39:7-13. [PMID: 17459735 DOI: 10.1016/j.bcmd.2007.02.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 02/15/2007] [Accepted: 02/19/2007] [Indexed: 11/20/2022]
Abstract
We examined the effect of extracellular terbium (Tb(3+)) and divalent metal cations (Ca(2+), Sr(2+), and Ba(2+)) on (86)Rb(+) influx into rabbit and human red blood cells. We found that Tb(3+) at 15 and 25 microM was a non-competitive inhibitor of (86)Rb(+) influx suggesting that Tb(3+) is not binding to the transport site. This result reduces the usefulness of Tb(3+) as a potential probe for the E(out) conformation (the conformation with the transport site facing extracellularly). Ba(2+), Sr(2+) and Ca(2+), at concentrations >50 mM, had minimal effects on Rb(+) influx into red blood cells (1 mM Rb-out). This suggests that the outside transport site is very specific for monovalent cations over divalent cations, in contrast to the inside transport site. We also found that chrysoidine (4-phenylazo-m-phenylenediamine) competes with Na(+) for ATPase activity and K(+) for pNPPase activity suggesting it is binding to the E(in) conformation. Chrysoidine and similar compounds may be useful as optical probes of the E(in) conformation.
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Affiliation(s)
- Matthew S Reifenberger
- Department of Medical Pharmacology and Physiology, School of Medicine, Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, USA
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8
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Kopinke D, Sasine J, Swift J, Stephens WZ, Piotrowski T. Retinoic acid is required for endodermal pouch morphogenesis and not for pharyngeal endoderm specification. Dev Dyn 2007; 235:2695-709. [PMID: 16871626 DOI: 10.1002/dvdy.20905] [Citation(s) in RCA: 66] [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: 11/10/2022] Open
Abstract
Because tissues from all three germ layers contribute to the pharyngeal arches, it is not surprising that all major signaling pathways are involved in their development. We focus on the role of retinoic acid (RA) signaling because it has been recognized for quite some time that alterations in this pathway lead to craniofacial malformations. Several studies exist that describe phenotypes observed upon RA perturbations in pharyngeal arch development; however, these studies did not address whether RA plays multiple roles at distinct time points during development. Here, we report the resulting phenotypes in the hindbrain, the neural crest-derived tissues, and the pharyngeal endoderm when RA synthesis is disrupted during zebrafish gastrulation and pharyngeal arch morphogenesis. Our results demonstrate that RA is required for the post-gastrulation morphogenesis and segmentation of endodermal pouches, and that loss of RA does not affect the length of the pharyngeal ectoderm or medial endoderm along the anterior-posterior axis. We also provide evidence that RA is not required for the specification of pharyngeal pouch endoderm and that the pharyngeal endoderm consists of at least two different cell populations, of which the pouch endoderm is sensitive to RA and the more medial pharyngeal endoderm is not. These results demonstrate that the developmental processes underlying pharyngeal arch defects differ depending on when RA signaling is disturbed during development.
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Affiliation(s)
- Daniel Kopinke
- University of Utah, Department of Neurobiology and Anatomy, Salt Lake City, Utah, USA
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9
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Doh-ura K, Tamura K, Karube Y, Naito M, Tsuruo T, Kataoka Y. Chelating Compound, Chrysoidine, Is More Effective in Both Antiprion Activity and Brain Endothelial Permeability Than Quinacrine. Cell Mol Neurobiol 2007; 27:303-16. [PMID: 17235694 DOI: 10.1007/s10571-006-9122-0] [Citation(s) in RCA: 15] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Accepted: 09/27/2006] [Indexed: 11/28/2022]
Abstract
1. As an extension of our previous study of quinacrine and its derivatives, chelating chemicals were screened to obtain more effective, better brain-permeable antiprion compounds using either prion-infected neuroblastoma cells or brain capillary endothelial cells.2. Eleven chemicals were found to have antiprion activity. Most of them shared a common structure consisting of benzene or naphthalene at either end of an azo bond. Structure-activity data suggest that chelating activity is not necessary but might contribute to the antiprion action.3. Chrysoidine, a representative compound found here, was about 27 times more effective in the antiprion activity and five times more efficiently permeable through the brain capillary endothelial cells than quinacrine was.4. These chemicals might be useful as compounds for development of therapeutics for prion diseases.
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Affiliation(s)
- Katsumi Doh-ura
- Department of Prion Research, Tohoku University Graduate School of Medicine, 2-1 Seiryo-cho, Aoba-ku, Sendai 980-8575, Japan.
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Kazakova N, Li H, Mora A, Jessen KR, Mirsky R, Richardson WD, Smith HK. A screen for mutations in zebrafish that affect myelin gene expression in Schwann cells and oligodendrocytes. Dev Biol 2006; 297:1-13. [PMID: 16839543 DOI: 10.1016/j.ydbio.2006.03.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [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: 10/28/2005] [Revised: 03/13/2006] [Accepted: 03/15/2006] [Indexed: 10/24/2022]
Abstract
Myelin is the multi-layered glial sheath around axons in the vertebrate nervous system. Myelinating glia develop and function in intimate association with neurons and neuron-glial interactions control much of the life history of these cells. However, many of the factors that regulate key aspects of myelin development and maintenance remain unknown. To discover new molecules that are important for glial development and myelination, we undertook a screen of zebrafish mutants with previously characterized neural defects. We screened for myelin basic protein (mbp) mRNA by in situ hybridization and identified four mutants (neckless, motionless, iguana and doc) that lacked mbp expression in parts of the peripheral and central nervous systems (PNS or CNS), despite the presence of axons. In all four mutants electron microscopy revealed that myelin-forming glia were present and had formed loose wraps around axons but did not form compact myelin. We found that addition of exogenous retinoic acid (RA) rescued mbp expression in neckless mutant embryos, which lack endogenous RA synthesis. Timed application of the RA synthesis inhibitor DEAB to wild type embryos showed that RA signalling is required at least 48 h before the onset of myelin protein synthesis in both CNS and PNS.
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Affiliation(s)
- Natalia Kazakova
- Department of Anatomy and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
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11
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Maves L, Kimmel CB. Dynamic and sequential patterning of the zebrafish posterior hindbrain by retinoic acid. Dev Biol 2006; 285:593-605. [PMID: 16102743 DOI: 10.1016/j.ydbio.2005.07.015] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.5] [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: 01/20/2005] [Revised: 06/19/2005] [Accepted: 07/15/2005] [Indexed: 11/24/2022]
Abstract
A prominent region of the vertebrate hindbrain is subdivided along the anterior-posterior axis into a series of seven segments, or rhombomeres. The identity of each rhombomere is specified by the expression of conserved transcription factors, including Krox-20, vHnf1, Val (Kreisler, Mafb) and several Hox proteins. Previous work has shown that retinoic acid (RA) signaling plays a critical role in regulating the expression of these factors and that more posterior rhombomeres require higher levels of RA than more anterior rhombomeres. Models to account for RA concentration dependency have proposed either a static RA gradient or increasing time periods of RA exposure. Here, we provide evidence against both of these models. We show that early zebrafish rhombomere-specification genes, including vhnf1 in r5-r6 and hoxd4a in r7, initiate expression sequentially in the hindbrain, each adjacent to the source of RA synthesis in paraxial mesoderm. By knocking down RA signaling, we show that progressively more posterior rhombomeres require increasingly higher levels of RA signaling, and vhnf1 and hoxd4a expression are particularly RA-dependent. RA synthesis is required just at the time of initiation, but not for maintenance, of vhnf1 and hoxd4a expression. Furthermore, a premature RA increase causes premature activation of vhnf1 and hoxd4a expression. Our results support a new model of dynamic RA action in the hindbrain, in which a temporally increasing source of RA is required to sequentially initiate progressively more posterior rhombomere identities.
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Affiliation(s)
- Lisa Maves
- Institute of Neuroscience, 1254 University of Oregon, Eugene, OR 97403-1254, USA.
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Karmakar R, Banik S, Chatterjee M. Inhibitory effect of vitamin D3 on 3'methyl-4-dimethyl-amino-azobenzene-induced rat hepatocarcinogenesis: a study on antioxidant defense enzymes. J Exp Ther Oncol 2002; 2:193-9. [PMID: 12416023 DOI: 10.1046/j.1359-4117.2002.01032.x] [Citation(s) in RCA: 15] [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] [Indexed: 01/21/2023]
Abstract
The anticarcinogenic effect of vitamin D3 (VD3) on 3,-methyl-4-dimethyl-amino-azobenzene (3,-Met-DAB)-induced hepatocarcinogenesis was investigated in male Sprague-Dawley rats. Anticancer efficacy of VD3 was estimated using different possible biomarkers, namely reduced glutathione (GSH) concentration, gamma-glutamyl transpeptidase (GGT) activity, glutathione S-transferase (GST) activity, glutathione reductase (GRd) activity, glutathione peroxidase (GPx) activity in hyperplastic nodules (HNs) and non-nodular surrounding parenchyma (NNSP) liver areas. VD3 was found to control the carcinogen-induced alterations in GSH level, GST, GGT, GRd and GPx activity both in HNs and NNSP liver areas during long-term exposure. A decrease in the number of HNs was also evident in the present investigation. VD3 was proved to be an effective antitumor drug during the initiation/promotion phases of hepatic carcinogenesis but the effect was found to be less prominent during initiation and promotion phases.
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Affiliation(s)
- Ranajit Karmakar
- Department of Zoology, Taki Government College, Taki, North 24 Parganas, West Bengal, India.
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13
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Affiliation(s)
- J E Russo
- Department of Chemistry, Whitman College, Walla Walla, Washington 99362, USA
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14
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Degawa M, Matsuda K, Arai H, Hashimoto Y. Lead nitrate inhibits the induction of CYP1A mRNAs by aromatic amines but not by aryl hydrocarbons in the rat liver. J Biochem 1996; 120:547-51. [PMID: 8902619 DOI: 10.1093/oxfordjournals.jbchem.a021448] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [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: 02/02/2023] Open
Abstract
The effects of lead nitrate on the induction of hepatic cytochrome P450IA (CYP1A) isoforms, mainly CYP1A2, by aromatic amines (2-methoxy-4-aminoazobenzene, 2-amino-3-methyl-9H-pyrido [2,3-b]indole and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) and aryl hydrocarbons (3-methylcholanthrene, benzo[a]pyrene and beta-naphthoflavone) in male F344 rats were examined at the levels of mRNA, protein and activity of the enzymes. Pretreatment of rats with lead nitrate suppressed the expression of hepatic CYP1A enzyme(s), especially CYP1A2, at both levels of protein and activity of the enzyme(s) by treatment with an aromatic amine or an aryl hydrocarbon. On the other hand, the lead nitrate pretreatment suppressed the induction of CYP1A mRNA(s) by an aromatic amine but not by an aryl hydrocarbon. These findings indicate that lead nitrate suppresses the expression of CYP1A enzymes at both stages of post-translation of mRNAs and transcriptional activation of the genes, and further suggest that the pathway for the transcriptional activation of the CYP1A genes by the aromatic amines is different from that by the aryl hydrocarbons.
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Affiliation(s)
- M Degawa
- Faculty of Pharmaceutical Sciences, Tohoku University, Sendai
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15
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Abstract
PURPOSE To investigate the influence of excess surfactant on transport kinetics in emulsions, using phenylazoaniline (PAA), benzocaine, benzoic acid and phenol as model drugs. Mineral oil was chosen as the oil phase and the nonionic surfactant, polyoxyethylene oleyl ether (Brij 97) as the emulsifier. METHODS Model drug transport in emulsions was investigated using side by side diffusion cells mounted with hydrophilic dialysis or hydrophobic membranes. A novel method, involving a combination of a membrane equilibrium technique and surface tension measurement (Wilhelmy plate method), was developed to determine surfactant critical micelle concentration (CMC) in the presence of O/W emulsions. Emulsion stability was determined by droplet size analysis as a function of time, temperature and dilution using photon correlation spectroscopy and a light blockage technique. Model drug mineral oil/water partition coefficients and aqueous solubilities were determined in the presence of surfactant. RESULTS The emulsion CMC value was used to calculate micellar phase concentration. The transport rates of PAA and benzocaine in emulsions increased with increase in Brij 97 micellar concentrations up to 1.0% w/v and then decreased at higher surfactant concentrations. The transport rates of the more hydrophilic compounds, benzoic acid (ionized form, pH 7.0) and phenol, were not affected by the presence of micellar phase. CONCLUSIONS Excess surfactant affected the transport rates of the model drugs in the emulsions depending on drug lipophilicity. Transport rates measured using side by side diffusion cells appeared to be governed by model drug partitioning rates from the oil to the continuous phases and by membrane type.
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Affiliation(s)
- K A Yoon
- Dept. of Pharmaceutical Science, School of Pharmacy, University of Connecticut, Storrs 06269-2092, USA
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Degawa M, Arai H, Kubota M, Hashimoto Y. Ionic lead, but not other ionic metals (Ni2+, Co2+ and Cd2+), suppresses 2-methoxy-4-aminoazobenzene-mediated cytochrome P450IA2 (CYP1A2) induction in rat liver. Biol Pharm Bull 1995; 18:1215-8. [PMID: 8845808 DOI: 10.1248/bpb.18.1215] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [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: 02/02/2023]
Abstract
Male F344 rats were pretreated with lead nitrate, nickel chloride, cobalt chloride or cadmium chloride, and their effects on the induction of cytochrome P450 (CYP) enzymes, mainly CYP1A2 enzyme, with 2-methoxy-4-aminoazobenzene (2-MeO-AAB) in the livers were comparatively examined by enzymatical, immunochemical, and molecular biological methods. When rats were pretreated with each ionic metal, the total CYP amount in the liver microsomes decreased, as compared with that of rats treated with 2-MeO-AAB alone. However, among the ionic metals used only lead reduced the levels of the mRNA and protein of CYP1A2 induced with 2-MeO-AAB in the rat liver, and decreased the microsomal activity (per CYP) for CYP1A2-mediated mutagenesis. Furthermore, ionic lead, but not other ionic metals, showed an ability to induce a placental form of glutathione S-transferase (GST-P). The level of CYP1A2 induced with 2-MeO-AAB was decreased along with increase in that of the induced GST-P.
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Affiliation(s)
- M Degawa
- Department of Hygienic Chemistry, Faculty of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
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17
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Golikov PP, Nikolaeva NI. [Effect of soluble streptocide on the function of type III glucocorticoid receptors in rat liver cytosol]. Patol Fiziol Eksp Ter 1995:21-3. [PMID: 7501429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effects of soluble streptocidum on the function of Type III glucocorticoid receptors in the hepatic cytosol were examined in Wistar rats weighing 180-200 g. The Scatchard Lainuiver-Berk established that soluble streptocidum resulted in a concentration-dependent increase in the number of Type III glucocorticoid receptor binding sites. At the same time the measured constant of interaction of labelled corticosterone with Type III glucocorticoid receptors and the dissociation constant of these complexes slightly changed with streptocidum. Soluble streptocidum-induced stimulation of the function of Type III glucocorticoid receptors was effected via the non-competitive type. Whether Type III glucocorticoid receptors directly involve in the mechanism of the antiphlogogenic effect of soluble streptocidum in aseptic inflammation is discussed in the paper.
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18
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Southan GJ, Szabó C, Thiemermann C. Inhibition of the induction of nitric oxide synthase by spermine is modulated by aldehyde dehydrogenase. Biochem Biophys Res Commun 1994; 203:1638-44. [PMID: 7524490 DOI: 10.1006/bbrc.1994.2374] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [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: 01/25/2023]
Abstract
The observation that spermine inhibits the endotoxin (lipopolysaccharide; LPS) induced production of nitric oxide (NO) in macrophages has been ascribed to the conversion of SP to active metabolites by the action of enzymes, such as diamine oxidases, found, for example, in bovine sera. Inhibitory effect is also observed with the oxidised metabolite of spermine, spermine dialdehyde (SDA). Inhibition appears to be at the level of induction of the inducible isoform of NO synthase (iNOS). Here we show that the activity of endogenous aldehyde dehydrogenase present in the cells influences the degree of inhibition seen with either spermine or SDA. Most significantly, inhibition of aldehyde dehydrogenase activity greatly increases (100 fold) the ability of spermine to inhibit the production of nitrite by LPS- induced macrophages. This is presumably by preserving aldehyde metabolites of spermine and thus increasing its action on the induction of iNOS. Thus, inhibition of aldehyde dehydrogenase activity in vitro or in vivo may be a useful approach to enhance the inhibitory effect of polyamines or polyamine aldehydes on iNOS induction.
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Affiliation(s)
- G J Southan
- William Harvey Research Institute, St. Bartholomew's Hospital Medical College, London, United Kingdom
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19
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von Engelhardt W, Gros G, Burmester M, Hansen K, Becker G, Rechkemmer G. Functional role of bicarbonate in propionate transport across guinea-pig isolated caecum and proximal colon. J Physiol 1994; 477:365-71. [PMID: 7523661 PMCID: PMC1155636 DOI: 10.1113/jphysiol.1994.sp020198] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [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: 01/25/2023] Open
Abstract
1. Unidirectional fluxes of propionate across isolated epithelia from the guinea-pig caecum and proximal colon were measured under short-circuit current conditions. In the caecum and proximal colon the serosal-to-mucosal propionate flux (JPrsm) was higher than mucosal-to-serosal flux (JPrms), resulting in a net secretory flux of propionate. 2. HCO3(-)-CO2-free solution reduced JPrms in the caecum and proximal colon markedly; JPrsm was not (caecum) or little (proximal colon) affected. The subsequent addition of acetazolamide caused a further decrease in JPrms in the proximal colon, but not in the caecum. 3. In HCO3(-)-containing solutions acetazolamide or ethoxzolamide inhibited JPrms; JPrsm was not affected. A macromolecular carbonic anhydrase inhibitor, prontosil-dextran, had no effect on propionate fluxes, indicating that the intracellular carbonic anhydrase is of importance for short-chain fatty acid transport. 4. Subsequent to carbonic anhydrase inhibition, mucosal addition of amiloride caused a slight further decrease of JPrms in the caecum and proximal colon; JPrsm was not affected. 5. Results support the view that a considerable proportion of short-chain fatty acids (SCFAs) is absorbed via a SCFA(-)-HCO3- exchange.
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Affiliation(s)
- W von Engelhardt
- Department of Physiology, School of Veterinary Medicine, Hannover, Germany
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20
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Vazzana I, Sparatore F, Fadda G, Manca C. N-[4-(R',R"-phenylazo)aryl]aminolupinanes with antitubercular activity. Farmaco 1993; 48:737-47. [PMID: 8373501] [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] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A set of twelve N-[4-(R-phenylazo)aryl]aminolupinanes (10a-c; 11a-i) was prepared by coupling the suitably substituted phenyldiazonium salts with N-(2,3-xylyl)-aminolupinane and with N-(5,6,7,8-tetrahydronaphth-1-yl)- aminolupinane. These compounds, as well as the N-(4-amino-2,3-xylyl)aminolupinane and the N-(4-amino-5,6,7,8-tetrahydronaphth-1-yl)-aminolupinane, that could be obtained from the former through an in vivo reductive cleavage of the azo group, exhibited a high activity against Mycobacterium tuberculosis H37RV with M.I.C. in the range 0.1-1 microgram/ml.
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Affiliation(s)
- I Vazzana
- Istituto di Scienze Farmaceutiche, Università di Genova
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21
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Abstract
Antibodies to 3-methoxy-4-aminoazobenzene (3-MeO-AAB) and 2-methoxy-4-aminoazobenzene (2-MeO-AAB) DNA adducts were raised in rabbits against in vitro-adducted DNA samples. The enzyme-linked immunosorbent assay (ELISA) was used to determine the sensitivity and specificity of these antibodies. They proved highly specific for the modified DNA used as the immunogen, but cross-reacted with each other. Moreover, they showed cross reactivity with DNA modified by 4-(o-tolylazo)-o-toluidine, but not by other carcinogens, such as 4-aminobiphenyl or 4-nitroquinoline 1-oxide. The 50% inhibition level of antibody binding in the competitive ELISA was at 10-20 fmol of modified base per assay (equivalent to 1-2 adducts per 10(6) bases). Immunohistochemical staining indicated that these antibodies bind specifically to nuclear components of the liver in rats given either 3-MeO-AAB or 2-MeO-AAB at the dose of 50 mg/kg body weight.
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Affiliation(s)
- M Kojima
- Laboratory of Biochemistry, Aichi Cancer Center Research Institute, Nagoya
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22
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Abstract
The change of cytochrome P450 (P450) isozymes in a early stage of hepatocarcinogenesis in male F344 rats has been studied. Liver microsomes were prepared from normal rats (group 1), rats treated with diethylnitrosamine (DEN) alone, which developed no hyperplastic nodules (group 2), and rats treated with DEN plus 2-acetylaminofluorene, which developed many hyperplastic nodules (group 3). The amount and activity of P450IA1 and P450IA2 expressed in the liver were analyzed by several immunological methods using monoclonal antibodies against the P450 isozymes and a mutagenicity test. In the group 2 and 3 rats, the total amount of P450 and the amount of P450IA2 were much smaller than those in the group 1 rats, and P450IA1 was detected only from the group 3 rats. As observed by immunohistochemistry, P450IA1 was prominent in hyperplastic nodules developed in the group 3 rats, and the distribution of P450IA1+ cells in individual nodules was heterogeneous. When the rats were treated with a P450 inducer, 3-methoxy-4-aminoazobenzene or 3-methylcholanthrene, both P450IA1 and P450IA2 were induced in all groups of rats; however, the induction rates of the P450 isozymes, especially that of P450IA2, in the group 3 rats were smaller than those in the group 1 and 2 rats. The present work demonstrated that P450IA1, which is responsible mainly for detoxication of aromatic amine carcinogens, increased in level along with the development of hyperplastic nodules, whereas P450IA2, which is responsible for mutagenic or carcinogenic activation of these carcinogens, decreased in its amount and inducibility.
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Affiliation(s)
- M Degawa
- Department of Hygienic Chemistry, Tohoku University, Sendai, Japan
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Kojima M, Degawa M, Hashimoto Y, Tada M. Different effects of DNA adducts induced by carcinogenic and noncarcinogenic azo dyes on in vitro DNA synthesis. Biochem Biophys Res Commun 1991; 179:817-23. [PMID: 1898405 DOI: 10.1016/0006-291x(91)91890-o] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [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: 12/29/2022]
Abstract
M13mp10 phage DNA modified with the carcinogen 3-methoxy-4-aminoazobenzene (3-MeO-AAB) or the noncarcinogen 2-methoxy-4-aminoazobenzene (2-MeO-AAB) was used as a template for E.coli DNA polymerase I. Analysis of the reaction products on DNA sequencing gels showed that with both types of compound the induced lesions blocked DNA synthesis, mainly at one base prior to guanine adducts, but that the inhibition by 3-MeO-AAB-adducts was substantially greater than that by 2-MeO-AAB-adducts. Thus different effects on DNA replication between 3-MeO-AAB- and 2-MeO-AAB-adducts might be a reflection of differences in their carcinogenic potency.
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Affiliation(s)
- M Kojima
- Laboratory of Biochemistry, Aichi Cancer Center Research Institute, Nagoya, Japan
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24
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Sandhu P, Chipman JK. Lack of release from hepatocytes in vitro or excretion in vivo of mutagenic chrysoidine metabolites. Toxicol Lett 1991; 58:43-50. [PMID: 1897005 DOI: 10.1016/0378-4274(91)90189-d] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Rat liver postmitochondrial supernatant (S9) converted the azo dyes chrysoidine Y and R to products that were mutagenic towards Salmonella typhimurium strain TA100. No such release of mutagens was demonstrated using intact rat hepatocytes as an activation system despite the fact that chrysoidine dyes cause unscheduled DNA synthesis in these cells. It appears that genotoxic products produced within hepatocytes either react within the cell or are detoxified prior to release. Following intraperitoneal administration of chrysoidine Y to rats (100 mg/kg i.p.) there was also no evidence of mutagenic or por-mutagenic products excreted in bile or urine. The S9-derived mutagens appear to be largely independent of bacterial acetylation since they were active in the acetylation-deficient strain TA98/1,8-DNP6 in addition to strain TA98. The ultimate mutagenic form(s) are therefore unlikely to be acetoxyarylamines.
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Affiliation(s)
- P Sandhu
- School of Biochemistry, University of Birmingham, U.K
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25
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Kojima M, Degawa M, Hashimoto Y, Tada M. 32P-postlabeling analysis of DNA adducts in rat livers after treatment with genotoxic and non-genotoxic 4-aminoazobenzene derivatives. Cancer Lett 1991; 58:199-204. [PMID: 1855196 DOI: 10.1016/0304-3835(91)90101-m] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [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: 12/29/2022]
Abstract
Formation of hepatic DNA adducts was studied in rats following intraperitoneal administration of a hepatocarcinogen, 3-methoxy-4-aminoazobenzene (3-MeO-AAB) and a non-hepatocarcinogen, 2-methoxy-4-aminoazobenzene (2-MeO-AAB). The 32P-post-labeling assay revealed 3-MeO-AAB to give more than 20-fold higher amounts of DNA adducts than did 2-MeO-AAB. Furthermore, five adducts, one of which accounted for over 70% of the total modified bases, were found in DNA from 3-MeO-AAB-treated rats, whereas only one adduct was apparent in 2-MeO-AAB-treated DNA. Our data thus suggested that the difference in hepatocarcinogenic activity between 3-MeO-AAB and 2-MeO-AAB might be, at least in part, dependent on quantitative and qualitative differences in their azo dye-DNA adduct formation in the rat liver.
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Affiliation(s)
- M Kojima
- Laboratory of Biochemistry, Aichi Cancer Center Research Institute, Kanokoden, Nagoya, Japan
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26
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Degawa M, Agatsuma T, Hashimoto Y. Species difference among experimental rodents in the activity and induction of cytochrome P-450 isozymes for mutagenic activation of carcinogenic aromatic amines. Jpn J Cancer Res 1990; 81:1253-8. [PMID: 2125995 PMCID: PMC5918006 DOI: 10.1111/j.1349-7006.1990.tb02687.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The expressions of hepatic microsomal cytochrome P-450 isozymes in male rats, mice, hamsters and guinea pigs were studied comparatively with or without an ip injection of a cytochrome P-450 inducer. The activity and quantity of microsomal cytochrome P-450 isozymes were determined respectively by a bacterial mutation assay with Salmonella typhimurium TA98 and immunochemical assays using monoclonal antibodies against rat cytochrome P-450 isozymes. 3-Methoxy-4-aminoazobenzene (3-MeO-AAB), 2-amino-3-methyl-9H-pyrido[2,3-b]indole acetate (MeA alpha C) and 3-methylcholanthrene were used as cytochrome P-450 inducers, and 7 carcinogenic aromatic amines including 3-MeO-AAB and MeA alpha C were used as substrates for the mutation assay. By means of these assays, we examined the species differences among rodents in the activity and induction rate of hepatic cytochrome P-450 isozymes responsible for the mutagenic activation of carcinogenic aromatic amines.
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Affiliation(s)
- M Degawa
- Department of Hygienic Chemistry, Tohoku University, Sendai
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27
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Hishinuma T, Degawa M, Masuko T, Hashimoto Y. Induction of cytochrome P-448 isozyme(s) in primary cultured rat hepatocytes by drugs which induce different isozymes in vivo. Biochem Biophys Res Commun 1987; 148:947-53. [PMID: 3318837 DOI: 10.1016/s0006-291x(87)80224-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [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: 01/05/2023]
Abstract
Effect of 2-methoxy-4-aminoazobenzene (2-MeO-AAB) and 3-methylcholanthrene (MC) on the induction of microsomal cytochrome P-448 isozymes in primary cultured rat hepatocytes was examined by means of immunochemical methods such as protein A-enzyme-linked immonosorbent assay and immuno-blots using anti-rat cytochrome P-448 monoclonal antibodies and by means of bacterial mutation tests. Although 2-MeO-AAB selectively induced cytochrome P-448H and MC induced both cytochrome P-448H and a low spin form of cytochrome P-448 (P-448L) in the liver of rats, addition of these chemicals to primary cultured rat hepatocytes resulted in selective induction of cytochrome P-448L, as determined by the immunological methods. This was substantiated by the bacterial mutation test using Salmonella typhimurium TA 98 bacteria and two aromatic amine substrates with different specificities to the cytochrome P-448 isozymes. These results suggest that the responses of rat hepatocytes to cytochrome P-450 inducers are different in in vivo and in vitro.
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Affiliation(s)
- T Hishinuma
- Department of Hygienic Chemistry, Tohoku University, Sendai, Japan
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28
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Abuaf PA, Kadlubar FF, Grunberger D. Circular dichroism of poly(dG-dC) modified by the carcinogens N-methyl-4-aminoazobenzene or 4-aminobiphenyl. Nucleic Acids Res 1987; 15:7125-36. [PMID: 3658674 PMCID: PMC306197 DOI: 10.1093/nar/15.17.7125] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [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: 01/06/2023] Open
Abstract
Poly(dG-dC) was modified to different extents by the carcinogens 4-aminobiphenyl (ABP) or N-methyl-4-aminoazobenzene (MAB). HPLC analysis of the enzymatically hydrolyzed modified polymers indicates that more than 90% of the ABP and 81% of the MAB modification occurs at the C8 position of guanine. The conformational changes of the unmodified and modified polymers were studied as a function of ethanol and magnesium ion concentrations by the use of circular dichroism (CD). The modified polymers show a CD inversion pattern similar to that of the salt-induced B to Z transition of poly(dG-dC). Both of the modified polymers require less salt or ethanol than the unmodified polymer for the inversion of the spectra. The amount of ethanol or magnesium needed to induce the inverted CD spectrum is inversely proportional to the percentage of bound ABP or MAB. These data indicate that ABP and MAB can enhance conversion from B to Z conformation in alternating purine-pyrimidine sequences.
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Affiliation(s)
- P A Abuaf
- Institute of Cancer Research/Comprehensive Cancer Center, College of Physicians and Surgeons, Columbia University, New York, NY 10032
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29
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Kelley M, Hantelle P, Safe S, Levin W, Thomas PE. Co-induction of cytochrome P-450 isozymes in rat liver by 2,4,5,2',4',5'-hexachlorobiphenyl or 3-methoxy-4-aminoazobenzene. Mol Pharmacol 1987; 32:206-11. [PMID: 3302669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
A multitude of xenobiotics have been demonstrated to co-induce either cytochromes P-450c and P-450d or cytochromes P-450b and P-450e in rat hepatic microsomes. Recently, the compounds 2,4,5,2',4',5'-hexachlorobiphenyl (HCB) and 3-methoxy-4-aminoazobenzene (3-MeO-AAB) have been suggested as selective inducers of cytochrome P-450b (Eur. J. Biochem. 151:67 (1985)) and P-450d (Biochem. Biophys. Res. Commun. 133:1072 (1985)), respectively. Since the identification of inducers with such unique characteristics would have implications with regard to the mechanism of induction of all four isozymes, we have examined the induction of cytochromes P-450b and P-450e by HCB and cytochromes P-450c and P-450d by 3-MeO-AAB in liver microsomes from adult male rats. Immunoblot analysis with monoclonal antibodies directed against cytochromes P-450b and P-450e indicate that HCB induces both isozymic species at the three dosage levels examined (10, 90, and 180 mg/kg). Similarly, 3-MeO-AAB does not appear to represent a unique inducer. Immunoblots of hepatic microsomes from animals treated with three different dosage regimens of 3-MeO-AAB demonstrate that, even at the lowest dosage level (50 mg/kg), both cytochromes P-450c and P-450d are induced. Moreover, immunoinhibition of 7-ethoxyresorufin O-deethylase (EROD) activity by monospecific antibody against either cytochrome P-450c or P-450d confirms this result. 3-MeO-AAB increases this enzyme activity 10-fold; approximately one-third of this induced activity is inhibited with monospecific anti-P-450c, while two-thirds is inhibited with monospecific anti-P-450d. This study also demonstrates that hepatic EROD activity is not an accurate estimate of cytochrome P-450c content since the majority of this enzyme activity in control and 3-MeO-AAB-treated rats is inhibited with monospecific anti-P-450d but not with monospecific anti-P-450c.
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Degawa M, Yamada H, Hishinuma T, Masuko T, Hashimoto Y. Organ selective induction of cytochrome P-448 isozymes in the rat by 2-methoxy-4-aminoazobenzene and 3-methylcholanthrene. J Biochem 1987; 101:1437-45. [PMID: 3312182 DOI: 10.1093/oxfordjournals.jbchem.a122013] [Citation(s) in RCA: 10] [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: 01/05/2023] Open
Abstract
Male Sprague Dawley rats were injected intraperitoneally with 2-methoxy-4-amino-azobenzene (2-MeO-AAB) or 3-methylcholanthrene (MC), and then the expression of microsomal cytochrome P-450 isozymes in liver and extrahepatic tissues was investigated by means of immunological methods and a bacterial mutation test. The results of protein A-enzyme-linked immunosorbent assaying and immunoblotting using anti-rat cytochrome P-448 monoclonal antibodies showed that MC induced at least two microsomal cytochrome P-448 isozymes, a high spin form (cytochrome P-448H) and a low spin form (cytochrome P-448L), in liver, but that it induced only cytochrome P-448L in extrahepatic tissues such as lung, kidney, small intestine, and colon. The results also indicated that, in contrast to MC, 2-MeO-AAB selectively induced microsomal cytochrome P-448H in liver but did not induce any cytochrome P-448 isozymes in extrahepatic tissues. The activities of 9,000 X g supernatants from the individual organs, as to the mutagenic conversion of 3 aromatic amines (3-amino-1-methyl-5H-pyrido(4,3-b)indole, 2-amino-6-methyldipyrido(1,2-a: 3',2'-d)-imidazole and 3-methoxy-4-aminoazobenzene), toward Salmonella typhimurium TA 98 bacteria were dependent upon the quantity and/or quality of the microsomal cytochrome P-448 isozymes in the organs.
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Affiliation(s)
- M Degawa
- Department of Hygienic Chemistry, Tohoku University, Miyagi
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31
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Abstract
The formation of DNA adducts in mouse liver has been demonstrated for numerous chemicals including members of most major classes of carcinogens. Considerably less is known about the persistence and repair of DNA adducts in mouse liver. Likewise, major gaps in present knowledge exist regarding the molecular dosimetry of DNA adducts and their potential for miscoding during continuous exposure to high versus low doses of carcinogens. A prime example of this is 2-acetylaminofluorene (2-AAF), the carcinogen used in the ED01 megamouse study. There are no molecular dosimetry studies on the DNA adducts of 2-AAF, even though such a unique data base exists for the dose-response relationship of mouse liver tumors. Reviewing the pertinent literature, identifying deficiencies, and conducting the required research will hopefully permit a better determination of the relevance of mouse liver tumors to man.
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Heming TA, Geers C, Gros G, Bidani A, Crandall ED. Effects of dextran-bound inhibitors on carbonic anhydrase activity in isolated rat lungs. J Appl Physiol (1985) 1986; 61:1849-56. [PMID: 2430932 DOI: 10.1152/jappl.1986.61.5.1849] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Effects of macromolecular Prontosil-dextran inhibitors (PD) on carbonic anhydrase (CA) activity in isolated rat lungs were studied. Isolated lungs were perfused with Krebs-Ringer bicarbonate (KRB) solutions containing no inhibitor, PD 100,000 (mol wt 100,000), PD 5,000 (mol wt 5,000), or low-molecular-weight inhibitors (Prontosil or acetazolamide). The time course of effluent perfusate pH equilibration was measured in a stop-flow pH electrode apparatus. Pulmonary CO2 excretion (Vco2) was monitored by continuously recording expired CO2 concentration. The lungs were ventilated with room air and perfused at 37 degrees C with KRB prebubbled with 5% CO2- 20% O2- 75% N2. The results obtained show that both the low-molecular-weight inhibitors and PD's caused postcapillary pH disequilibria (delta pH) in effluent perfusate. However, only acetazolamide and Prontosil caused a reduction in Vco2. These results suggest that there is an intravascular CA, presumably associated with endothelial cell membranes, that is accessible to all inhibitors used and is responsible in part for equilibration of the CO2- HCO3- -H+ reactions in the perfusate but, under the conditions used, does not affect CO2 excretion; and there is an extravascular (possibly intracellular) CA that can be inhibited by low-molecular-weight inhibitors, is primarily responsible for enhanced CO2 transfer across the alveolar-capillary barrier (perhaps via facilitation of CO2 diffusion), and is in part responsible for pH equilibration.
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Degawa M, Kojima M, Sato Y, Hashimoto Y. Induction of a high spin form of microsomal cytochrome P-448 in rat liver by 4-aminoazobenzene derivatives. Biochem Pharmacol 1986; 35:3565-70. [PMID: 3768039 DOI: 10.1016/0006-2952(86)90627-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Male Sprague-Dawley rats were treated with 4-aminoazobenzene derivatives or other drug metabolizing enzyme inducers such as phenobarbital, 3-methylcholanthrene and isosafrole. The expression of hepatic microsomal cytochrome P-450 of the rats, principally that of a high spin form of cytochrome P-448 (cytochrome P-448H), was assessed by a bacterial mutation test and by immunological methods. The results of the mutation test with use of Salmonella typhimurium TA9 and 3 aromatic amine substrates showed that 2-methoxyl, 3-methoxyl and 2',3-dimethoxyl derivatives of AAB and methyl derivatives of AAB such as o-aminoazotoluene, N-methyl-4-aminoazobenzene and N,N-dimethyl-4-aminoazobenzene have a large capacity for the selective induction of cytochrome P-448H. Activity of the cytochrome increased by 6 hr after an azo dye treatment, reached a maximum after 24 hr, and then declined. In contrast, 4'-methoxy-AAB has a small, and AAB has no, capacity for the cytochrome induction. The aminoazo dye-induced enzymes differ in their substrate specificities from those induced with 3-methylcholanthrene or phenobarbital, and the induced enzyme was identified to be cytochrome P-448H, as determined by an enzyme-linked immunosorbent assay and immunoblotting with use of anti-cytochrome P-448 monoclonal antibodies. These observations indicate that several methoxyl and methyl derivatives of 4-aminoazobenzene are potent and selective inducers of cytochrome P-448H in the rat.
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Degawa M, Kojima M, Masuko T, Hishinuma T, Hashimoto Y. 3-Methoxy-4-aminoazobenzene, a selective inducer for a high spin form of cytochrome P-448 in rat liver microsomes. Biochem Biophys Res Commun 1985; 133:1072-7. [PMID: 4084302 DOI: 10.1016/0006-291x(85)91245-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Treatment of Sprague Dawley rats with 3-methoxy-4-aminoazobenzene (3-MeO-AAB) resulted in striking increase of the activity of hepatic microsomal cytochrome P-450s which could efficiently catalyze the mutagenic activation of hepatocarcinogenic aromatic amines such as a tryptophan-pyrolysate component, Trp P-2, and a glutamic acid-pyrolysate component, Glu P-1. The 3-MeO-AAB-induced cytochrome P-450 (3-MeO-AAB-P-450) was examined for the molecular character by immuno-Western blotting using monoclonal antibody to 3-methylcholanthrene-induced cytochrome P-448 (P-448H; m.w. 54,000).
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Degawa M, Kojima M, Hashimoto Y. 3-Methoxy-4-aminoazobenzene, a unique carcinogenic aromatic amine as a substrate for cytochrome-P-450-mediated mutagenesis. Mutat Res 1985; 152:125-9. [PMID: 3934534 DOI: 10.1016/0027-5107(85)90054-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Rat liver microsomal enzyme(s) that catalyze mutagenic activation of a carcinogenic aminoazo dye, 3-methoxy-4-aminoazobenzene (3-MeO-AAB), was studied by virtue of the Salmonella typhimurium TA98 assay using o-aminoazotoluene (OAT) as the control. Male Wistar rats were pretreated with phenobarbital (PB), 3-methylcholanthrene (MC) or polychlorinated biphenyl (PCB), and the liver microsomal activities for mutagenic activation of 3-MeO-AAB and OAT were examined. In agreement with the reported results on several carcinogenic aromatic amines, MC pretreatment resulted in greater activation of microsomal activity in the OAT mutagenesis (about a 4-fold increase as compared to the untreated control) than did PB (1.5-fold increase). By contrast, the mutagenic activation of 3-MeO-AAB is found to be more efficiently catalyzed by those enzyme(s) that are induced by PB pretreatment (4-fold increase) than by those that are induced by MC (1.8-fold increase). The induced enzymes that principally mediate the mutagenic activation of these azo dyes are indicated to be cytochrome P-450s, because the mutagenic activation was strongly inhibited by addition of cytochrome P-450 inhibitors such as 2-diethylaminoethyl-2,2-diphenylvalerate (SKF 525A) and 7,8-benzoflavone. These data suggest that 3-MeO-AAB is a unique carcinogenic aromatic amine as a substrate for mutagenic activation via catalysis of those cytochrome P-450s that are induced by PB pretreatment.
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Medvedeva ND, Antipanova EM. [Proliferation of poorly differentiated cells in the rat liver after a single injection of the hepatocarcinogen 4-dimethylaminoazobenzine and its noncarcinogenic analog]. Tsitologiia 1983; 25:1333-5. [PMID: 6419425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
With the aid of autoradiography, the proliferation of non-differentiated (oval and transitional) cells in rat liver induced by a single injection of hepatocarcinogen 4-dimethylaminoazobenzene and its non-carcinogenic analogue has been studied. These cells are characterized by a high proliferative activity reaching its maximum 4 days after injection of both the agents. Later on, the proliferative activity decreased due probably to differentiation of such cells.
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Chernysheva MD, Medvedeva ND. [Changes in tryptophan pyrrolase activity in the rat liver after a single injection of the hepatocarcinogen 4-dimethylaminoazobenzene and its noncarcinogenic analog]. Tsitologiia 1982; 24:615-617. [PMID: 6808731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
A single injection of hepatocarcinogen 4-dimethylaminoazobenzene in rats results in considerable changes of tryptophanpyrrolase of the liver. A non-carcinogenic analog 4-diethylaminoazobenzene causes similar, although a milder shift. The observed injury of definitive hepatocytes and proliferation of oval and transition cells, due to the toxic effect of both the agents, may be one of the causes of changes in tryptophan pyrrolase activity.
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Hashimoto Y, Watanabe HK, Degawa M. Mutagenicity of 4-aminoazobenzene, N-hydroxy-4-aminoazobenzene, 4-nitrosoazobenzene, 4-nitroazobenzene, and their ring methoxylated derivatives on Salmonella. Gan 1981; 72:921-9. [PMID: 7042447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The mutagenicities of 4-aminoazobenzene (AAB), N-hydroxy-4-aminoazobenzene, 4-nitroazobenzene, and their 2-, 3-, 4'-methoxyl and 2,5-dimethoxyl derivatives, and 2- and 3-methoxy-4-nitrosoazobenzene were examined on Salmonella typhimurium TA98 and TA100. The activities of AAB dyes upon S-9 metabolic activation were related to their carcinogenic activities in the rat. The potent carcinogen 3-methoxy-AAB was a potent mutagen for both tester strains. The moderate or weak carcinogens 4'-methoxy-AAB and AAb were moderate or weak mutagens for one or both of the tester strains. The non-carcinogens 2-methoxy-AAB and 2,5-dimethoxy-AAB were non-mutagenic. In contrast to AAB dyes, N-hydroxy-AAB dyes showed greater mutagenicity than the mother AAB dyes, without S-9 treatment. 4-Nitroazobenzene dyes and 4-nitrosoazobenzene dyes showed mutagenicity without S-9 treatment, and the activities were related to those of the corresponding N-hydroxy-AAB dyes. All 4-nitroazobenzene dyes were mutagenic in the presence of S-9, suggesting the production of mutagens other than N-hydroxy-AAB dyes by the S-9 treatment. The cytotoxicity of azo dyes to bacteria had no apparent relation to the mutagenic activity of the azo dyes. Incubation of 4-nitroazobenzene dyes with TA100 bacteria yielded N-hydroxy-AAB dyes. The synthesis and properties of new N-hydroxy-AAB dyes, 4-nitroazobenzene dyes and 4-nitrosoazobenzene dyes are described.
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Watanabe HK, Hashimoto Y. Unscheduled DNA synthesis induced by 4-aminoazobenzene, N-hydroxy-4-aminoazobenzene, and their derivatives in primary cultures of rat and mouse hepatocytes. Gan 1981; 72:930-6. [PMID: 7341341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The ability of carcinogenic and non-carcinogenic aminoazo dyes to induce unscheduled DNA synthesis (UDS) in primary cultures of hepatocytes of 3 strains of rats and 2 strains of mice was examined by means of microautoradiography. Azo dyes tested were 4-aminoazobenzene (AAB) and 4 of its ring methoxyl (MeO) derivatives, their N-hydroxy (N-OH) derivatives, N-methyl-4-aminoazobenzene (MAB) and its N-bezoyloxy derivative, and N,N-dimethyl-4-aminoazobenzene (DAB). All carcinogenic aminoazo dyes (AAB, 3-MeO-AAB, 4'-MeO-AAB, MAB and DAB), but not the non-carcinogenic dyes (2-MeO-AAB and 2,5-diMeO-AAB), induced UDS in rat hepatocytes as well as mouse hepatocytes. N-Hydroxy derivatives of AAB and its 3- and 4'-MeO derivatives elicited higher levels of UDS than did the corresponding mother aminoazo dyes. N-OH-2-MeO-AAB was as inactive with rat hepatocytes as the mother dye. N-OH-2,5-diMeO-AAB, however, elicited a definite level of UDS, in contrast to the mother 2,5-diMeO-AAB. N-Benzoyloxy-MAB, a prototype compound of the ultimate carcinogenic metabolite of MAB, was as active as the mother MAB. N,-OH-3-MeO-AAB induced UDS more rapidly than did 3-MeO-AAB. The UDS elicited by 3-MeO-AAB was found to end within a few hours after releasing the hepatocytes from the azo dye.
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Kaledin VI, Glazko TT, Zakharova NN. [Disruption of tyrosine aminotransferase induction by hydrocortisone in the livers of mice which had received o-aminoazotoluene]. Dokl Akad Nauk SSSR 1979; 244:233-7. [PMID: 33019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Degawa M, Miyairi S, Hashimoto H. Electrophilic reactivity and mutagenicity of ring-methyl derivatives of N-acyloxy-N-methyl-4-aminoazobenzene and related azo dyes. Gan 1978; 69:367-74. [PMID: 352785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Williams GM. Detection of chemical carcinogens by unscheduled DNA synthesis in rat liver primary cell cultures. Cancer Res 1977; 37:1845-51. [PMID: 404038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Unscheduled DNA synthesis was observed in primary rat liver cell cultures treated with members of five different classes of chemical procarcinogens requiring enzymatic activation as well as with a direct-acting carcinogen. In total, ten carcinogens and one related analog not commonly accepted as carcinogenic were active, while one weak carcinogen and four noncarcinogens were inactive. The production of unscheduled DNA synthesis by this spectrum of chemical carcinogens indicates that these cultures have substantially retained the metabolic capability of liver for activating diverse procarcinogens. Thus, such cultures may be useful for detecting the ability of chemicals to interact with DNA and, thereby, assigning them priority for consideration as potential cancer-causing agents.
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Patel NT, Holoubek V. Protein composition of liver nuclear ribonucleoportein particles of rats fed carcinogenic aminoazo dyes. Biochem Biophys Res Commun 1976; 73:112-9. [PMID: 826249 DOI: 10.1016/0006-291x(76)90504-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Tokiwa T, Nishi M, Sato J. Effects of 3'-methyl-4-dimethylaminoazobenzene and 4-aminoazobenzene on plating efficiency, mitotic index, and macromolecular synthesis of cultured liver cells. Acta Med Okayama 1976; 30:303-9. [PMID: 137657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The response of a cultured liver cell line to azo dyes was investigated by the application of 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) and 4-aminoazobenzene (AB) with observation of, in particular, the changes which occurred in plating efficiency, macromolecular synthesis and mitotic indices. The results were as follows. (1) The application of 3'-Me-DAB resulted in a decrease in size of colonies and plating efficiency of both J-5-2 cells (derived from 7-day-old rat liver tissues) and cells of the colonical clone, J-5-2cl. (2) AB caused greater inhibition of plating efficiency than did 3'-Me-DAB. (3) Both 3'-Me-DAB and AB inhibited synthesis of DNA but not of RNA or of protein. (4) AB exhibited a greater inhibitory effect on mitotic indices than did 3'-Me-DAB.
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Abstract
The mutagenicity of N,N-dimethyl-4-aminoazobenzene and N-methyl-4-aminoazobenzene and their derivatives was shown on Salmonella typhimurium TA100 and TA98. S-9 Mix, obtained from rat liver after injection of polychlorinated biphenyl, was abligatory for their mutagenic action. N-Acetoxy-N-methyl-4-aminoazobenzene and N-benzoyloxy-N-methyl-4-aminoazobenzene and their 4'-methoxycarbonyl derivatives were also mutagenic on TA100 and TA98 and did not require metabolic activation by S-9 Mix. It is suggested that the carcinogenic effects of azo dyes may involve modification of DNA.
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