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Myden A, Stalford SA, Fowkes A, White E, Hirose A, Yamada T. Enhancing developmental and reproductive toxicity knowledge: A new AOP stemming from glutathione depletion. Curr Res Toxicol 2023; 5:100124. [PMID: 37808440 PMCID: PMC10556594 DOI: 10.1016/j.crtox.2023.100124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/14/2023] [Accepted: 09/13/2023] [Indexed: 10/10/2023] Open
Abstract
Integrated approaches to testing and assessments (IATAs) have been proposed as a method to organise new approach methodologies in order to replace traditional animal testing for chemical safety assessments. To capture the mechanistic aspects of toxicity assessments, IATAs can be framed around the adverse outcome pathway (AOP) concept. To utilise AOPs fully in this context, a sufficient number of pathways need to be present to develop fit for purpose IATAs. In silico approaches can support IATA through the provision of predictive models and also through data integration to derive conclusions using a weight-of-evidence approach. To examine the maturity of a developmental and reproductive toxicity (DART) AOP network derived from the literature, an assessment of its coverage was performed against a novel toxicity dataset. A dataset of diverse compounds, with data from studies performed according to OECD test guidelines TG-421 and TG-422, was curated to test the performance of an in silico model based on the AOP network - allowing for the identification of knowledge gaps within the network. One such gap in the knowledge was filled through the development of an AOP stemming from the molecular initiating event 'glutathione reaction with an electrophile' leading to male fertility toxicity. The creation of the AOP provided the mechanistic rationale for the curation of pre-existing structural alerts to relevant key events. Integrating this new knowledge and associated alerts into the DART AOP network will improve its coverage of DART-relevant chemical space. In addition, broadening the coverage of AOPs for a particular regulatory endpoint may facilitate the development of, and confidence in, robust IATAs.
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Affiliation(s)
- Alun Myden
- Lhasa Limited, Granary Wharf House, 2 Canal Wharf, Leeds LS11 5PS, United Kingdom
| | - Susanne A. Stalford
- Lhasa Limited, Granary Wharf House, 2 Canal Wharf, Leeds LS11 5PS, United Kingdom
| | - Adrian Fowkes
- Lhasa Limited, Granary Wharf House, 2 Canal Wharf, Leeds LS11 5PS, United Kingdom
| | - Emma White
- Lhasa Limited, Granary Wharf House, 2 Canal Wharf, Leeds LS11 5PS, United Kingdom
| | - Akihiko Hirose
- Division of Risk Assessment, Center for Biological Safety and Research, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Japan
| | - Takashi Yamada
- Division of Risk Assessment, Center for Biological Safety and Research, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki 210-9501, Japan
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Luong XTH, Shen YS, Liang C, Chen YT. Evaluation of various natural weeds and reaction conditions for reductive degradation of 1,3-dinitrobenzene. JOURNAL OF HAZARDOUS MATERIALS 2023; 454:131467. [PMID: 37104957 DOI: 10.1016/j.jhazmat.2023.131467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 04/09/2023] [Accepted: 04/20/2023] [Indexed: 05/19/2023]
Abstract
1,3-Dinitrobenzene (1,3-DNB) is listed by the USEPA as a priority pollutant. 1,3-DNB has two nitro functional groups (-NO2) bound to the benzene ring, with a +III nitrogen oxidation states, and strong electronegativity, and therefore can be reductively degraded by gaining electrons. Weeds that contain a high proportion of polyphenols can supply electrons and act as natural reducing agents. This study investigated the potential of various weeds to reductively remove 1,3-DNB from aqueous phase. The Taguchi L9 Orthogonal experimental design method was used to explore the optimum operational parameters. According to the analyzed characteristics of weeds, including total phenol content, antioxidant capacity, metal chelating capacity, reducing capacity, and environmental adaptability, the weed Sphagneticola trilobata, containing 11.93 mg of gallic acid equivalent per gram of weed (mg-GAE/g-weed), was selected for 1,3-DNB degradation experiments. The results showed that the optimum reaction conditions for the degradation of 1,3-DNB in the aqueous phase using Sphagneticola trilobata were: pH 3, a weed dose of 10 g/L, reaction time of 14 day, and initial 1,3-DNB concentration of 0.5 mM. According to ANOVA analysis, the weed dose was the most significant factor in the experiment, and each 1 mg of 1,3-DNB degraded required 120 mg of dry weeds.
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Affiliation(s)
- Xuyen Thi Hong Luong
- Department of Environmental Engineering, National Chung Hsing University, 145 Xingda Road, Taichung 402, Taiwan
| | - Yu-Shan Shen
- Department of Environmental Engineering, National Chung Hsing University, 145 Xingda Road, Taichung 402, Taiwan
| | - Chenju Liang
- Department of Environmental Engineering, National Chung Hsing University, 145 Xingda Road, Taichung 402, Taiwan.
| | - Yao-Tsung Chen
- Apollo Technology CO., LTD. 6A New Design Building, No. 22, Section 3, Zhongshan N. Rd., Zhongshan Dist., Taipei 104, Taiwan
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Wolde GS, Kuo DH, Abdullah H. Solar-light-driven ternary MgO/TiO 2/g-C 3N 4 heterojunction photocatalyst with surface defects for dinitrobenzene pollutant reduction. CHEMOSPHERE 2022; 307:135939. [PMID: 35940421 DOI: 10.1016/j.chemosphere.2022.135939] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 07/26/2022] [Accepted: 07/31/2022] [Indexed: 06/15/2023]
Abstract
Defect engineering and heterojunction are promising strategies to improve the photocatalytic performance of particular catalyst through effective charge carrier separation and transport. Herein, we developed Z-scheme MgO/TiO2/g-C3N4 ternary heterojunction photocatalyst with surface defects and effective charge separation for reduction of recalcitrant dinitrobenzene isomers under simulated solar light irradiation. Mott-Schottky (MS) plot analysis and electron spin resonance (ESR) radical trapping experiment suggested the formation of Z-scheme heterojunction at the interface of TiO2/g-C3N4, which played a crucial role in the electron-hole separation. Incorporating MgO into the structure further enhances charge separation via Ti3+ and oxygen vacancy (OV) defects formation at the TiO2/MgO interface as confirmed by electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS) analyses. Besides, the surface basicity of MgO enhanced conversion of dinitrobenzene (DNB) isomers through formation of nitrophenylhydroxylamine intermediate which can easily be reduced to phenylenediamines (PDAs). As confirmed by high performance liquid chromatography (HPLC) analysis, excellent selectivity for PDAs (95-98%) was achieved in 90 min with ternary MgO/TiO2/g-C3N4 composite compared to the binary MgO/TiO2 and TiO2/g-C3N4. A possible reaction pathway and photocatalytic reduction mechanism were proposed and elucidated. This work demonstrated an effective strategy to reduce recalcitrant dinitrobenzene isomers using efficient, low-cost, and environmental benign photocatalyst with a facile identification of reaction intermediates.
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Affiliation(s)
- Girma Sisay Wolde
- Department of Materials Science and Engineering, National Taiwan University of Science and Technology, No.43, Sec. 4, Keelung Road, Taipei, 10607, Taiwan
| | - Dong-Hau Kuo
- Department of Materials Science and Engineering, National Taiwan University of Science and Technology, No.43, Sec. 4, Keelung Road, Taipei, 10607, Taiwan.
| | - Hairus Abdullah
- Department of Materials Science and Engineering, National Taiwan University of Science and Technology, No.43, Sec. 4, Keelung Road, Taipei, 10607, Taiwan
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Peiris LDC, Chathu P, Perera DDBD, Moore HD. 1,3-Dinitrobenze-Induced Genotoxicity Through Altering Nuclear Integrity of Diploid and Polyploidy Germ Cells. Dose Response 2019; 17:1559325819876760. [PMID: 31579111 PMCID: PMC6757507 DOI: 10.1177/1559325819876760] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 07/28/2019] [Accepted: 08/27/2019] [Indexed: 01/28/2023] Open
Abstract
1,3-Dinitrobenzene (mDNB) is a widely used intermediate in commercial products and causes testicular injury. However, genotoxic effects upon low-level exposure are poorly understood. The present study evaluated the effects of very low-chronic doses of mDNB on sperm nuclear integrity. Male hamsters were treated with 1.5 mg/kg/d/4 wks (group A), 1.5 mg/kg/mDNB/d/week/4 weeks (group B), 1.0 mg/kg/mDNB/3 d/wk/4 wks (group C), or polyethylene glycol 600 (control). Nuclear integrity of distal cauda epididymal sperm was determined using the sperm chromatin structure assay and acridine orange staining (AOS). The germ cell nuclear integrity was assessed by the comet assay. Testicular histopathology was conducted to evaluate the sensitive stages. The comet assay revealed denatured nuclear DNA in group A (in diploid and polyploid cells from weeks 2-5); respectively at week 4 and weeks 3 to 4 in groups B and C. According to AOS, only group A animals exhibited denatured sperm DNA (weeks 1 and 3). The effective sperm count declined from weeks 1 to 6. Mean sperm DNA denaturation extent, percentage cells outside the main population, and standard deviation indicated altered sperm nuclear integrity in group A. Same animals exhibited progressive disruption of the Sertoli cells, while groups B and C exhibited damages on germ cells. The results suggest that mDNB affects sperm nuclear integrity at very low chronic doses targeting cell-specific testicular damage.
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Affiliation(s)
- L. Dinithi C. Peiris
- Department of Zoology (Centre for Biotechnology), University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - Prathitha Chathu
- Department of Zoology (Centre for Biotechnology), University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - D. D. B. D. Perera
- Department of Zoology (Centre for Biotechnology), University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - Harry D. Moore
- Department of Biomedical Science, Centre for Stem Cell Biology, The University of Sheffield, Sheffield, United Kingdom
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Tilinca M, Florea A. Ultrastructural analysis of early toxic effects produced by bee venom phospholipase A2 and melittin in Sertoli cells in rats. Toxicon 2017; 141:94-103. [PMID: 29229236 DOI: 10.1016/j.toxicon.2017.12.039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/15/2017] [Accepted: 12/06/2017] [Indexed: 10/18/2022]
Abstract
In this study, we aimed to investigate the testicular toxicity of two molecules derived from bee venom (BV): phospholipase A2 (PlA2) and melittin (Mlt). Ultrastructural effects of purified BV PlA2 and Mlt were assessed consecutive to repeated dose (30 days) and acute toxicity studies. For the subchronic treatment, PlA2 and Mlt were injected in daily doses equivalent to those released by a bee sting (105 μg PlA2/kg/day and 350 μg Mlt/kg/day), while in the acute treatment their doses corresponded to those released by 100 bee stings (9.3 mg PlA2/kg and 31 mg Mlt/kg). Both PlA2 and Mlt affected the Leydig cells and the cells in seminiferous tubules, the Sertoli cells first of all. PlA2 injection resulted in detachment of the Sertoli cells from the surrounding cells, and extracellular vacuolations, cytoplasmic vacuolations in their basal region and in branches as well, detachment of spermatids, residual bodies and sometimes even spermatocytes into the lumen, changes that had a higher magnitude after the acute treatment. Mlt injection induced similar ultrastructural alterations, but more severe, including degeneration of cellular organelles and cellular necrosis, resulting into rarefaction of the seminiferous epithelium; the ultrastructural changes had a higher magnitude after the 30 repeated dose treatment. We concluded that either of the two molecules tested here, PlA2 and Mlt, were Sertoli cells toxicants at the used doses, and they participated both in the BV testicular toxicity. We consider the observed changes as part of a preceding mechanism of the more severe alterations produced by the BV. It also remains possible that these early unspecific changes reported here could represent the response of the SCs not only to the components of bee venom, but to molecules of other venoms as well. The Sertoli cells were the primary target of PlA2 and Mlt in the spermatogenic epithelium, and their alteration led to further degenerative changes of the germ cells. Since the exposure to PlA2 and Mlt caused severe alteration, including cell death and detachment of immature germ cells into the lumen, we may also conclude that the bee venom molecules had a potential to interfere with normal progression of spermatogenesis. All the degenerative changes observed in the Sertoli cells were accompanied with changes of the Leydig cells.
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Affiliation(s)
- Mariana Tilinca
- Department of Cell and Molecular Biology, Faculty of Medicine, University of Medicine and Pharmacy, Târgu-Mureş, Romania
| | - Adrian Florea
- Department of Cell and Molecular Biology, Faculty of Medicine, "Iuliu Haţieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania.
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Florea A, Puică C, Hamed S, Tilinca M, Matei H. Histopathological and ultrastructural changes experimentally induced by bee venom in seminiferous epithelium via structural-functional alteration of Sertoli cells. Micron 2017; 102:1-14. [PMID: 28830057 DOI: 10.1016/j.micron.2017.07.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 07/29/2017] [Accepted: 07/29/2017] [Indexed: 12/13/2022]
Abstract
We tested here the ability of bee venom (BV) to interfere with spermatogenesis in rats in two experimental conditions. The histopathological changes were assessed with brightfield microscopy using a novel staining technique, based on methylene blue, orange G and ponceau xylidine. Transmission electron microscopy was also used to identify fine subcellular changes. BV injection for 30days in daily doses of 700μg BV/kg resulted in reducing testicular weight, along with significant larger diameters of seminiferous tubules and reduced number of Sertoli cells (SCs). SCs were vacuolated, detached from the basement membrane, many necrosed, leading to the basement membrane denudation. Germ cells layers were separated by empty spaces conferring a rarefied aspect to the tissue, and spermatids were detached into lumen. Thus, the seminiferous epithelium was significantly thinned. Many Leydig cells (LCs) were in a necrotic state, with disrupted plasma membrane and without smooth endoplasmic reticulum. The acute treatment with a single LD50 of 62mgBV/kg, was followed by focal disruptions of the basement membrane and localized areas of necrosis, mainly affecting the SCs. Most of the observed SCs as well as some spermatogonia were highly vacuoled, empty spaces being observed within the epithelium. The SCs count was significantly decreased. Spermatids had also the tendency of separation from the SCs, and the significant larger diameter of the tubules found was associated with a thicker epithelium. Many LCs were necrosed, with disrupted plasma membrane, swollen mitochondria, no endoplasmic reticulum and implicitly showing rarefied cytoplasm. We concluded that BV was a testicular toxicant affecting both the LCs and the seminiferous tubules. The SCs cells represented the primary target site of BV whose effects were next extended upon the germ cells. In all cells, BV triggered unspecific degenerative changes that could impaire spermatogenesis. The present study also proposes an alternative staining technique very useful in assessing the histopathological aspects of spermatogenesis.
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Affiliation(s)
- Adrian Florea
- Department of Cell and Molecular Biology, Faculty of Medicine, "Iuliu Haţieganu" University of Medicine and Pharmacy, 6 Louis Pasteur St., 400349 Cluj-Napoca, Romania.
| | - Constantin Puică
- Department of Physiology, Institute of Biological Research, 48 Gheorgh Bilaşcu St., 400015 Cluj-Napoca, Romania
| | - Sami Hamed
- Department of Cell and Molecular Biology, Faculty of Medicine, "Iuliu Haţieganu" University of Medicine and Pharmacy, 6 Louis Pasteur St., 400349 Cluj-Napoca, Romania
| | - Mariana Tilinca
- Department of Cellular and Molecular Biology, Faculty of Medicine, University of Medicine and Pharmacy, 38 Gheorghe Marinescu St., 540139 Târgu-Mureş, Romania
| | - Horea Matei
- Department of Cell and Molecular Biology, Faculty of Medicine, "Iuliu Haţieganu" University of Medicine and Pharmacy, 6 Louis Pasteur St., 400349 Cluj-Napoca, Romania
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Matsuyama T, Yabe K, Kuwata C, Ito K, Ando Y, Iida H, Mori K. Transcriptional profile of ethylene glycol monomethyl ether-induced testicular toxicity in rats. Drug Chem Toxicol 2017; 41:105-112. [DOI: 10.1080/01480545.2017.1320406] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Takuya Matsuyama
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd, Tokyo, Japan
| | - Koichi Yabe
- Daiichi Sankyo India Pharma Pvt. Ltd, Gurgaon, Haryana, India
| | - Chiharu Kuwata
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd, Tokyo, Japan
| | - Kazumi Ito
- Translational Medicine and Clinical Pharmacology Department, Daiichi Sankyo Co., Ltd, Tokyo, Japan
| | - Yosuke Ando
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd, Tokyo, Japan
| | - Hiroshi Iida
- Laboratory of Zoology, Graduate School of Agriculture, Kyushu University, Fukuoka, Japan
| | - Kazuhiko Mori
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd, Tokyo, Japan
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Reis MMS, Moreira AC, Sousa M, Mathur PP, Oliveira PF, Alves MG. Sertoli cell as a model in male reproductive toxicology: Advantages and disadvantages. J Appl Toxicol 2015; 35:870-83. [DOI: 10.1002/jat.3122] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 12/21/2014] [Accepted: 12/26/2014] [Indexed: 01/11/2023]
Affiliation(s)
- Mariana M. S. Reis
- Department of Microscopy, Laboratory of Cell Biology, UMIB-FCT, Institute of Biomedical Sciences Abel Salazar (ICBAS); University of Porto; Porto Portugal
| | - Ana C. Moreira
- Department of Microscopy, Laboratory of Cell Biology, UMIB-FCT, Institute of Biomedical Sciences Abel Salazar (ICBAS); University of Porto; Porto Portugal
| | - Mário Sousa
- Department of Microscopy, Laboratory of Cell Biology, UMIB-FCT, Institute of Biomedical Sciences Abel Salazar (ICBAS); University of Porto; Porto Portugal
| | - Premendu P. Mathur
- Department of Biochemistry and Molecular Biology, School of Life Sciences; Pondicherry University, Pondicherry, India & KIIT University; Bhubaneswar India
| | - Pedro F. Oliveira
- CICS - UBI - Health Sciences Research Centre; University of Beira Interior; Covilhã Portugal
| | - Marco G. Alves
- CICS - UBI - Health Sciences Research Centre; University of Beira Interior; Covilhã Portugal
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Rouquié D, Tinwell H, Blanck O, Schorsch F, Geter D, Wason S, Bars R. Thyroid tumor formation in the male mouse induced by fluopyram is mediated by activation of hepatic CAR/PXR nuclear receptors. Regul Toxicol Pharmacol 2014; 70:673-80. [DOI: 10.1016/j.yrtph.2014.10.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 10/03/2014] [Accepted: 10/08/2014] [Indexed: 10/24/2022]
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Tinwell H, Colombel S, Blanck O, Bars R. The screening of everyday life chemicals in validated assays targeting the pituitary-gonadal axis. Regul Toxicol Pharmacol 2013; 66:184-96. [PMID: 23590819 DOI: 10.1016/j.yrtph.2013.04.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 03/30/2013] [Accepted: 04/08/2013] [Indexed: 11/24/2022]
Abstract
Ten structurally diverse chemicals (vitamins C, B9, B6, B3, sucrose, caffeine, gingerol, xanthan gum, paracetamol, ibuprofen) deemed intrinsic to modern life but not considered as endocrine active, were tested in vitro using the human estrogen receptor transcriptional activation (hERTa) and the H295R steroidogenesis assays. All were inactive in the hERTa assay but paracetamol, gingerol, caffeine and vitamin C affected steroidogenesis in vitro from 250, 25, 500 and 750 μM respectively. One molecule, caffeine, was further tested in rat pubertal assays at the tumorigenic dose-level and at dose-levels relevant for human consumption. In females pubertal parameters (vaginal opening, estrus cycle), ovarian weight and Fsh and prolactin transcript levels were affected. In males, plasma progesterone levels and prostate and seminal vesicle weights were affected. Although the current regulatory focus is synthetic chemicals that can cause adverse effects on the hypothalamus-pituitary-gonadal axis, our data infer that the range of natural chemicals with the potential to affect this axis may be extensive and is probably overlooked. Thus, to avoid regulation of an overwhelming number of chemicals, a weight of evidence approach, combining hazard identification and characterization with exposure considerations, is needed to identify those chemicals of real regulatory concern.
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Affiliation(s)
- H Tinwell
- Bayer SAS, 16 rue Jean-Marie Leclair, CP 106, 69266 Lyon Cedex 09, France.
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Sonee M, Bogdan N, Hall L, Bryant S, Vinken P. The inhibin B response to the testicular toxicant 1, 3 dinitrobenzene in male rats. ACTA ACUST UNITED AC 2013; 98:29-34. [PMID: 23348823 DOI: 10.1002/bdrb.21038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 12/12/2012] [Indexed: 11/11/2022]
Abstract
BACKGROUND This study was conducted as part of an ILSI-HESI International Life Sciences Institute-Health & Environmental Sciences Institute consortium effort to assess the utility of circulating Inhibin B as an early biomarker of Sertoli cell-specific testicular toxicity in rats. 1, 3-Dinitrobenzene (1,3-DNB) was selected as a testicular toxicant in this study as it is known to target Sertoli cells. METHODS 1,3-DNB (2 and 6 mg/kg/day) or control (corn oil) was administered orally to male rats for two or five consecutive days. Blood was collected from rats treated for 2 days on days 1 and 2 and from rats treated for 5 days on days 1, 3, and 5. The resulting serum was evaluated for Inhibin B and follicle stimulating hormone. At the end of the treatment periods, the testes were removed, weighed, and examined histopathologically. RESULTS Daily administration of 1,3-DNB resulted in decreased testis weight only on day 5 and only at the high dose (6 mg/kg/day). There was a time-dependent increase in incidence and severity of testicular findings characterized by degeneration of the germinal epithelium with loss of pachytene spermatocytes and vacuolization of the Sertoli cells in the seminiferous tubules at the high dose. Inhibin B levels in 1,3-DNB-treated animals were decreased with treatment only on day 5 at the high dose; there were no associated changes in follicle stimulating hormone. CONCLUSIONS Changes in serum Inhibin B levels were detected only in association with moderate or severe testicular toxicity as evidenced by histopathology and is therefore considered to be of limited value as a biomarker for Sertoli cell toxicity.
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Affiliation(s)
- Manisha Sonee
- Drug Safety Sciences, Janssen Research & Development, LLC Raritan, NJ, USA.
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