1
|
Furukawa S, Tsuji N, Hayashi S, Kuroda Y, Kimura M, Hayakawa C, Takeuchi K, Sugiyama A. The effects of β-naphthoflavone on rat placental development. J Toxicol Pathol 2019; 32:275-282. [PMID: 31719754 PMCID: PMC6831496 DOI: 10.1293/tox.2019-0047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 07/23/2019] [Indexed: 01/21/2023] Open
Abstract
The morphological effects of β-naphthoflavone (β-NF) on placental development in
pregnant rats were examined. β-NF, administered to pregnant rats intraperitoneally at 15
mg/kg bw from gestation day (GD) 9 to GD 14, had no effect on maternal body weight gain,
mortality, or clinical sign. In the β-NF-exposed rats, intrauterine growth retardation
(IUGR) rates increased on GDs 17 and 21, although there was no effect on fetal mortality
rate, fetal or placental weight, or external fetal abnormality. Histopathologically, β-NF
induced apoptosis and inhibition of cell proliferation of the trophoblastic septa in the
labyrinth zone, resulting in its poor development. In the basal zone, β-NF induced
spongiotrophoblast apoptosis and delayed glycogen islet regression, resulting in their
cystic degeneration. β-NF-induced CYP1A1 expression was detected in the endothelial cells
of the fetal capillaries in the labyrinth zone and in the endothelial cells of the spiral
arteries in the metrial gland, but not in any trophoblasts. This indicates that CYP1A1 is
inducible in the endothelial cells of the fetal capillaries in the labyrinth zone, and
that these cells have an important role in metabolizing CYP1A1 inducers crossing the
placental barrier.
Collapse
Affiliation(s)
- Satoshi Furukawa
- Biological Research Laboratories, Nissan Chemical Corporation, 1470 Shiraoka, Shiraoka-shi, Saitama 349-0294, Japan
| | - Naho Tsuji
- Biological Research Laboratories, Nissan Chemical Corporation, 1470 Shiraoka, Shiraoka-shi, Saitama 349-0294, Japan
| | - Seigo Hayashi
- Biological Research Laboratories, Nissan Chemical Corporation, 1470 Shiraoka, Shiraoka-shi, Saitama 349-0294, Japan
| | - Yusuke Kuroda
- Biological Research Laboratories, Nissan Chemical Corporation, 1470 Shiraoka, Shiraoka-shi, Saitama 349-0294, Japan
| | - Masayuki Kimura
- Biological Research Laboratories, Nissan Chemical Corporation, 1470 Shiraoka, Shiraoka-shi, Saitama 349-0294, Japan
| | - Chisato Hayakawa
- Biological Research Laboratories, Nissan Chemical Corporation, 1470 Shiraoka, Shiraoka-shi, Saitama 349-0294, Japan
| | - Kazuya Takeuchi
- Biological Research Laboratories, Nissan Chemical Corporation, 1470 Shiraoka, Shiraoka-shi, Saitama 349-0294, Japan
| | - Akihiko Sugiyama
- Veterinary Clinical Pathology, Faculty of Veterinary Medicine Okayama University of Science, 1-3 Ikoinooka, Imabari, Ehime 794-8555, Japan
| |
Collapse
|
2
|
Frazier KS, Engelhardt JA, Fant P, Guionaud S, Henry SP, Leach MW, Louden C, Scicchitano MS, Weaver JL, Zabka TS. Scientific and Regulatory Policy Committee Points-to-consider Paper*. Toxicol Pathol 2015; 43:915-34. [DOI: 10.1177/0192623315570340] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Drug-induced vascular injury (DIVI) is a recurrent challenge in the development of novel pharmaceutical agents. Although DIVI in laboratory animal species has been well characterized for vasoactive small molecules, there is little available information regarding DIVI associated with biotherapeutics such as peptides/proteins or antibodies. Because of the uncertainty about whether DIVI in preclinical studies is predictive of effects in humans and the lack of robust biomarkers of DIVI, preclinical DIVI findings can cause considerable delays in or even halt development of promising new drugs. This review discusses standard terminology, characteristics, and mechanisms of DIVI associated with biotherapeutics. Guidance and points to consider for the toxicologist and pathologist facing preclinical cases of biotherapeutic-related DIVI are outlined, and examples of regulatory feedback for each of the mechanistic types of DIVI are included to provide insight into risk assessment.
Collapse
Affiliation(s)
| | | | | | | | | | - Michael W. Leach
- Pfizer—Drug Safety Research and Development, Andover, Massachusetts, USA
| | | | | | | | | |
Collapse
|
3
|
Andersson H, Helmestam M, Zebrowska A, Olovsson M, Brittebo E. Tamoxifen-Induced Adduct Formation and Cell Stress in Human Endometrial Glands. Drug Metab Dispos 2009; 38:200-7. [DOI: 10.1124/dmd.109.029488] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
4
|
Effect of 2-amino-9H-pyrido[2,3-b]indole (AalphaC), a carcinogenic heterocyclic amine present in food, on atherosclerotic plaque development in apoE deficient mice. Toxicol Lett 2009; 185:73-8. [PMID: 19103270 DOI: 10.1016/j.toxlet.2008.11.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2008] [Revised: 11/24/2008] [Accepted: 11/27/2008] [Indexed: 11/22/2022]
Abstract
There is experimental and epidemiological evidence demonstrating that polycyclic aromatic hydrocarbons (PAHs) are involved in the pathogenesis of cardiovascular diseases. However, heterocyclic amines (HAs), a class of carcinogenic compounds present in food, which share many biochemical features with PAHs, have not received much attention. Previous reports have shown that the heterocyclic amine 2-amino-9H-pyrido[2,3-b]indole (AalphaC) binds and metabolically affects endothelial cells in animal models suggesting a potential role in vascular remodeling. The present study investigates the effect of exposure to HAs on atherosclerotic plaque development in the apoE(-/-) mice. We observed that animals treated with AalphaC developed atherosclerotic lesions characterized by lower lipid content but richer in inflammatory cells and collagen content when compared with control animals. Moreover, atherosclerotic plaques from AalphaC-treated apoE(-/-) mice were also smaller with a marked reduction in the tunica media thickness. Furthermore, total cholesterol levels were significantly reduced in AalphaC-treated apoE(-/-) mice. In contrast to what has been previously reported for PAHs, we provide for the first time evidence that HAs may protect against cardiovascular disease by inducing stable atherosclerotic plaques and reducing circulating cholesterol levels. These results open new avenues to further investigate the role of these food-borne carcinogens in cardiovascular physiology and pathology.
Collapse
|
5
|
Kopf PG, Huwe JK, Walker MK. Hypertension, cardiac hypertrophy, and impaired vascular relaxation induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin are associated with increased superoxide. Cardiovasc Toxicol 2008; 8:181-93. [PMID: 18850075 DOI: 10.1007/s12012-008-9027-x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Accepted: 09/23/2008] [Indexed: 02/07/2023]
Abstract
The mechanisms by which 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) increases the incidence of human cardiovascular disease are not known. We investigated the degree to which cardiovascular disease develops in mice following subchronic TCDD exposure. Adult male C57BL/6 mice were dosed with vehicle or 300 ng TCDD/kg by oral gavage three times per week for 60 days. Blood pressure was recorded by radiotelemetry and aortic endothelial function was assessed by acetylcholine-induced vasorelaxation. Mean arterial pressure of TCDD-exposed mice was increased significantly by day 4 and between days 7-10, 25-35, and 45-60 with two periods of normalization on days 11-24 and days 36-39. Consistent with a prolonged period of systemic hypertension, heart weight was increased and was associated with concentric left ventricular hypertrophy. Significant increases in superoxide production also were observed in the kidney, heart, and aorta of TCDD-exposed mice. Furthermore, increased aortic superoxide resulted in endothelial dysfunction as demonstrated by significant impairment of acetylcholine-induced vasorelaxation in TCDD-exposed mice, which was restored by tempol, a superoxide dismutase (SOD) mimetic. Our model is the first to definitely demonstrate that sustained AhR activation by TCDD increases blood pressure and induces cardiac hypertrophy, which may be mediated, in part, by increased superoxide.
Collapse
Affiliation(s)
- Phillip G Kopf
- College of Pharmacy, University of New Mexico Health Sciences Center, MSC09 5360, 2502 Marble NE, Albuquerque, NM 87131, USA.
| | | | | |
Collapse
|
6
|
Brunnberg S, Andersson P, Lindstam M, Paulson I, Poellinger L, Hanberg A. The constitutively active Ah receptor (CA-AhR) mouse as a potential model for dioxin exposure—Effects in vital organs. Toxicology 2006; 224:191-201. [PMID: 16766111 DOI: 10.1016/j.tox.2006.04.045] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2006] [Revised: 04/04/2006] [Accepted: 04/05/2006] [Indexed: 11/28/2022]
Abstract
The dioxin/aryl hydrocarbon receptor (AhR) mediates most, if not all, toxic effects of dioxins and functions as a ligand-activated transcription factor regulating transcription of a battery of genes. In order to study the mechanisms behind the toxicity of ligands of the Ah receptor we have created a transgenic mouse model expressing a constitutively active Ah receptor (CA-AhR). The mutant Ah receptor is expressed and functionally active in all organs studied. The purpose of the present study was to characterize histopathologically, the phenotype of the CA-AhR with regard to the liver, kidney, lung, heart, spleen and thymus of male and female transgenic CA-AhR mice. Moreover, cell-specific activity of the CA-AhR using up-regulation of the AhR target gene CYP1A1 as a marker, was also examined. The relative weight of liver, kidney and heart were increased while relative thymus weight was decreased. Furthermore, slight morphological lesions of the liver, kidney and spleen was seen. Expression of CYP1A1 was found in cells corresponding to endothelial cells in all of the organs studied. In some tissues additional cell types, such as hepatocytes, renal tubuli cell and Clara cells expressed CYP1A1. Both the effects on organ weights and the cellular expression of CYP1A1 in CA-AhR mice correspond well to observations in TCDD-exposed mice. In conclusion, this characterization further support that the CA-AhR mouse is a useful model for life-long continuous low-level activity of the AhR, i.e. the dioxin exposure situation of humans of the general population.
Collapse
Affiliation(s)
- Sara Brunnberg
- Institute of Environmental Medicine, Karolinska Institutet, Nobels väg 13, Solna, Stockholm, Sweden.
| | | | | | | | | | | |
Collapse
|
7
|
Yun CH, Chung DK, Yoon K, Han SH. Involvement of reactive oxygen species in the immunosuppressive effect of 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), a food-born carcinogenic heterocyclic amine. Toxicol Lett 2006; 164:37-43. [PMID: 16386858 DOI: 10.1016/j.toxlet.2005.11.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2005] [Revised: 11/17/2005] [Accepted: 11/17/2005] [Indexed: 11/29/2022]
Abstract
A heterocyclic amine, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) is one of the potent food-borne dietary carcinogens derived mainly from burnt meat products. In the present study, we investigated the immunosuppressive effect of Trp-P-1 on the blastogenesis of lymphocytes prepared from spleen and thymus of Balb/c mice. Trp-P-1 inhibited, in a dose-dependent manner, proliferation of splenocytes in response to a B-cell mitogen, lipopolysaccharide and of both splenocytes and thymocytes in response to T-cell mitogens, concanavalin A and phytohemagglutinin, or non-receptor-mediated stimuli, phobol 12-myristate 13-acetate/ionomycin. Interestingly, Trp-P-1-inhibited proliferation in the splenocytes was restored almost completely by N-acetyl-l-cysteine (NAC) and partially by glutathione (GSH), whereas no effect was found when superoxide dismutase and catalase were used. Moreover, Trp-P-1 enhanced the mitogen-induced NF-kappaB binding activity to its cognate binding sequences, which is known to be mediated by intracellular reactive oxygen species (ROS) generation. Collectively, these results suggest that the immunosuppressive effect of Trp-P-1 is mediated by suppressing blastogenesis of lymphocytes via intracellular generation of ROS sensitive to NAC and/or GSH.
Collapse
Affiliation(s)
- Cheol-Heui Yun
- Laboratory Sciences Division, International Vaccine Institute, SNU Research Park, San 4-8 Boncheon-7 dong, Kwanak-gu, Seoul 151-818, Republic of Korea
| | | | | | | |
Collapse
|
8
|
Garrick RA, Woodin BR, Wilson JY, Middlebrooks BL, Stegeman JJ. Cytochrome P4501A is induced in endothelial cell lines from the kidney and lung of the bottlenose dolphin, Tursiops truncatus. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2006; 76:295-305. [PMID: 16290286 DOI: 10.1016/j.aquatox.2005.10.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2005] [Revised: 10/14/2005] [Accepted: 10/15/2005] [Indexed: 05/05/2023]
Abstract
Marine mammals respond to the presence of polycyclic and planar halogenated aromatic hydrocarbons (PAH or PHAH) with the induced expression in endothelium of cytochrome P4501A1, regulated through the aryl hydrocarbon receptor (AHR) transcription factor. Physiological responses in other animals, such as edema and inflammation indicate that the endothelium may be compromised by exposure to AHR agonists, which are ubiquitous in the marine environment. In other mammals and fish the cellular and molecular consequences of exposure to AHR agonists have been elucidated in cultured endothelial cells. We have cultured and characterized cetacean endothelial cells (EC) and used them in induction studies. Endothelial cells were cultured from the lung and kidney of the bottlenose dolphin, Tursiops truncates, and exposed to the AHR agonists beta-naphthoflavone (betaNF) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). betaNF (1-3 microM) induced significant increases in CYP1A1 (O-deethylation of 7-ethoxyresorufin to resorufin; EROD) activity to 3.6 and 0.92 pmol/mg/min in lung and kidney EC, respectively. TCDD was more potent than betaNF, and more efficacious, with maximum induction of CYP1A1 activity of 10.1 and 15.2 pmol/mg/min in lung and kidney EC at 3-10 nM TCDD. The differential response indicates that the lung and kidney endothelial cells in culture retain the ability to respond in a selective manner to specific stimuli. Both the molecular mechanisms of induction and the physiological consequences, especially in the vasculature, of toxicant exposure can be studied in this system.
Collapse
Affiliation(s)
- Rita Anne Garrick
- Department of Natural Sciences, Fordham University, New York, NY 10023, USA.
| | | | | | | | | |
Collapse
|
9
|
He XJ, Ejiri N, Nakayama H, Doi K. Effects of pregnancy on CYPs protein expression in rat liver. Exp Mol Pathol 2005; 78:64-70. [PMID: 15596063 DOI: 10.1016/j.yexmp.2004.08.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2004] [Indexed: 10/26/2022]
Abstract
A body of evidence suggests that pregnancy may be responsible for the depression in the microsomal enzyme activity and the reduction in the total content of cytochrome P450 (CYP) in the rat liver. However, changes in expression of individual CYP isozyme remain poorly known. The current study was designed to examine the changes in CYPs protein expression in the liver of F344 rats in midpregnancy and late pregnancy by Western blot analysis and immunohistochemistry. Total nine antirat CYPs antibodies (CYP1A1, CYP2B1/CYP2B2, CYP2C6, CYP2C12, CYP2D1, CYP2D4, CYP2E1, CYP3A1, and CYP4A1) were used. In comparison with age-matched nonpregnant control rats, there were significant decreases in hepatic levels of CYP2B2, CYP2C6, and CYP4A1 in midpregnancy (day 13) and CYP2B2, CYP2C6, CYP4A1, CYP1A1, CYP2B1, and CYP2E1 in late pregnancy (day 19). The expression of CYP2C12, CYP2D1, and CYP 3A1 did not differ between nonpregnant and pregnant rats, and CYP2D4 was not detectable in microsomal proteins obtained from nonpregnant and pregnant rats at a protein loading of 20 mug total protein per lane. Immunohistochemistry showed that there were no differences in the distribution and degree of immunostainability for the abovementioned antibodies to nine CYPs between pregnant and nonpregnant rats.
Collapse
Affiliation(s)
- Xi Jun He
- Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Yayoi 1-1-1, Bunkyo-ku, Tokyo, Japan
| | | | | | | |
Collapse
|
10
|
Garrick RA, Woodin BR, Stegeman JJ. CYTOCHROME P4501A INDUCED DIFFERENTIALLY IN ENDOTHELIAL CELLS CULTURED FROM DIFFERENT ORGANS OF ANGUILLA ROSTRATA. ACTA ACUST UNITED AC 2005; 41:57-63. [PMID: 15926861 DOI: 10.1290/0409063.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Endothelial cells are a structural barrier and an active regulator of many bodily processes. Cytochrome P4501A (CYP1A) activity is induced in the endothelium of teleosts and mammals exposed to lipophilic xenobiotics, such as polycyclic aromatic hydrocarbons, and can have significant consequences for endothelial functions. We exposed cultures of characterized endothelial cells from the heart, kidney, and rete mirabile of the eel, Anguilla rostrata, to aryl hydrocarbon receptor (AhR) agonists. In heart endothelial cells, the maximum response (based on O-deethylation of 7-ethoxyresorufin to resorufin [EROD] activity) to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 113 pmol/mg/min, was at 1 nM TCDD and the peak response to beta-napthoflavone (betaNF), 135 pmol/mg/min, was at 3 microM betaNF. The maximum response to TCDD in the kidney endothelial cells is 12 pmol/mg/min at 0.3 nM TCDD. The rete mirabile capillary endothelial cells responded minimally or not at all to exposure to TCDD and betaNF. Both the heart and kidney endothelial cells (but not the rete mirabile capillary cells) have a low level of EROD activity (12.7 and 5.2 pmol/mg/min, respectively) in untreated or dimethylsulfoxide-treated cells. The robust response of the heart endothelial cells to induction and the lack of response in the rete mirabile capillary endothelial cells indicate that these cells are a good resource to use to investigate the physiological consequences of AhR agonist exposure and CYP1A induction in different areas of the vasculature.
Collapse
Affiliation(s)
- Rita Anne Garrick
- Department of Natural Sciences, Fordham University, 113 W. 60th Street, New York, New York 10023, USA.
| | | | | |
Collapse
|
11
|
Annas A, Brittebo E, Hellman B. Evaluation of benzo(a)pyrene-induced DNA damage in human endothelial cells using alkaline single cell gel electrophoresis. Mutat Res 2000; 471:145-55. [PMID: 11080670 DOI: 10.1016/s1383-5718(00)00127-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The alkaline version of the 'comet assay' was used to evaluate DNA damage in human umbilical vein endothelial cells (HUVEC) exposed to 0.1, 1.0, or 10 microM benzo(a)pyrene for 90min. The genotoxicity was monitored in HUVEC pretreated with the Ah-receptor agonist beta-naphthoflavone (BNF), previously shown to induce cytochrome P4501A1 (CYP1A1) activity in these cells, and in vehicle-treated HUVEC with only constitutive levels of this enzyme. Increased DNA damage was observed only in cells that had been exposed to 10 microM benzo(a)pyrene, cells exposed to BNF being subjected to the most extensive damage. The CYP1A/B-inhibitor alpha-naphthoflavone (ANF) reduced the benzo(a)pyrene-induced DNA-damage in the BNF-treated HUVEC to the same level as in the uninduced cells. The fact that benzo(a)pyrene induced DNA damage in vehicle-treated HUVEC suggests that there may be at least one alternative route of bioactivation for benzo(a)pyrene in these cells. Consequently, judging from the present results it seems as if tobacco-related polycyclic aromatic hydrocarbons (PAHs) may disrupt the function of the endothelial lining in blood vessels with low monooxygenase activity. It is proposed that exposure to Ah receptor agonists via, for example, tobacco smoke, may enhance the DNA-damaging effects of smoke-related genotoxic PAHs in human endothelial cells. The role of PAHs in endothelial dysfunction of tobacco smokers should therefore be further studied.
Collapse
Affiliation(s)
- A Annas
- Department of Pharmaceutical Biosciences/Toxicology, Uppsala University, Box 594, SE-751 24 Uppsala, Sweden
| | | | | |
Collapse
|
12
|
Annas A, Granberg AL, Brittebo EB. Differential response of cultured human umbilical vein and artery endothelial cells to Ah receptor agonist treatment: CYP-dependent activation of food and environmental mutagens. Toxicol Appl Pharmacol 2000; 169:94-101. [PMID: 11076701 DOI: 10.1006/taap.2000.9054] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the present study, 7-ethoxyresorufin O-deethylase (EROD), 7, 12-dimethylbenz[a]anthracene (DMBA)-hydroxylase, and covalent binding of (3)H-labeled 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole ((3)H-Trp-P-1) and (3)H-DMBA were examined in human umbilical vein endothelial cells (HUVEC) and human umbilical artery endothelial cells (HUAEC) exposed to the aryl hydrocarbon (Ah) receptor agonist beta-naphthoflavone (BNF) or vehicle only. The results revealed a marked induction of enzymatic activity in BNF-treated HUVEC compared with vehicle-treated cells, whereas no similar response was observed in BNF-treated HUAEC. EROD, DMBA hydroxylase, and covalent binding of (3)H-Trp-P-1 and (3)H-DMBA in BNF-treated HUVEC were reduced in the presence of the CYP1A inhibitor ellipticine. Addition of other CYP1A inhibitors alpha-naphthoflavone, miconazole, 1-ethynylpyrene, 1-(1-propynyl)pyrene), or the CYP1A substrate ethoxyresorufin to the incubation buffer of BNF-treated HUVEC reduced covalent binding of (3)H-Trp-P-1 by 93-98%. Western blot analysis confirmed an induction of CYP1A1 in BNF-treated HUVEC, but not in BNF-treated HUAEC. CYP1A1 was, however, detected in both vehicle- and BNF-treated HUAEC. The results showed that BNF exposure induced CYP1A1 and metabolic activation of xenobiotics in HUVEC, whereas the catalytic activity remained low in BNF-treated HUAEC. Our results suggest that endothelial lining of human veins may be a target for adverse effects of xenobiotics activated into reactive metabolites by Ah receptor-regulated enzymes. Several studies have detected CYP1A1 in endothelial linings, whereas expression of CYP1A2 and CYP1B1 seems to be negligible at this site. This suggests that the metabolic activation and covalent binding of (3)H-Trp-P-1 and (3)H-DMBA in HUVEC are most likely mediated by CYP1A1.
Collapse
Affiliation(s)
- A Annas
- Department of Pharmaceutical Biosciences, Biomedical Centre, Uppsala University, SE-751 24, Sweden
| | | | | |
Collapse
|
13
|
Dey A, Jones JE, Nebert DW. Tissue- and cell type-specific expression of cytochrome P450 1A1 and cytochrome P450 1A2 mRNA in the mouse localized in situ hybridization. Biochem Pharmacol 1999; 58:525-37. [PMID: 10424773 DOI: 10.1016/s0006-2952(99)00110-0] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
We used in situ hybridization to examine organ- and cell type-specific constitutive and 3-methylcholanthrene (3MC)-inducible cytochrome P450 (CYP)1A1 and CYP1A2 mRNA expression in various tissues of the C57BL/6N mouse. In situ hybridization was carried out 10 hr after the mice had received intraperitoneal 3MC, or vehicle alone. We detected levels of 3MC-induced CYP1A1 mRNA in: liver (centrilobular, more so than periportal, regions); lung (Clara Type II cells much more than Type I epithelial cells); brain, especially endothelial cells lining the vascular surface of the choroid plexus; the digestive tract (duodenum > jejunum > ileum > colon > esophagus > stomach--in particular, the villous epithelium, plus cells surrounding glands in the lamina propria); renal corpuscles of the kidney; the ovary (medulla more so than cortex); and the endothelial cells of blood vessels throughout the animal. Constitutive CYP1A1 mRNA was not detectable by in situ hybridization in any of these tissues. In contrast, constitutive CYP1A2 mRNA was measurable in liver, and 3MC-inducible CYP1A2 mRNA was observed only in liver, lung, and duodenum (having cell-type locations similar to those of CYP1A1); the other above-mentioned tissues were negative for CYP1A2 mRNA. These data demonstrate the striking differences in tissue- and cell type-specific expression between the two members of the mouse Cypla subfamily. Because of the ubiquitous nature of 3MC-inducible CYP1A1 throughout the animal rather than just "portals of entry," these results support our hypothesis that CYP1A1, induced by particular endogenous signals in various tissues and cell types, might participate in one or more critical life processes--in addition to its well-established role of metabolism of polycyclic hydrocarbons, certain drugs, and other environmental pollutants.
Collapse
Affiliation(s)
- A Dey
- Center for Environmental Genetics and Department of Environmental Health, University of Cincinnati Medical Center, OH 45267-0056, USA
| | | | | |
Collapse
|