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Bowman CJ, Campion SN, Catlin NR, Nowland WS, Stethem CM, Radi ZA, Cappon GD. Reversible effects on female rat fertility with abrocitinib, a Janus kinase 1 inhibitor. Birth Defects Res 2024; 116:e2345. [PMID: 38716582 DOI: 10.1002/bdr2.2345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Revised: 04/16/2024] [Accepted: 04/20/2024] [Indexed: 06/05/2024]
Abstract
BACKGROUND Abrocitinib is a Janus kinase (JAK) 1 selective inhibitor approved for the treatment of atopic dermatitis. Female reproductive tissues were unaffected in general toxicity studies, but an initial female rat fertility study resulted in adverse effects at all doses evaluated. A second rat fertility study was conducted to evaluate lower doses and potential for recovery. METHODS This second study had 4 groups of 20 females each administered abrocitinib (0, 3, 10, or 70 mg/kg/day) 2 weeks prior to cohabitation through gestation day (GD) 7. In addition, 2 groups of 20 rats (0 or 70 mg/kg/day) were dosed for 3 weeks followed by a 4-week recovery period before mating. All mated females were evaluated on GD 14. RESULTS No effects were observed at ≤10 mg/kg/day. At 70 mg/kg/day (29x human exposure), decreased pregnancy rate, implantation sites, and viable embryos were observed. All these effects reversed 4 weeks after the last dose. CONCLUSIONS Based on these data and literature on the potential role of JAK signaling in implantation, we hypothesize that these effects may be related to JAK1 inhibition and, generally, that peri-implantation effects such as these, in the absence of cycling or microscopic changes in nonpregnant female reproductive tissues, are anticipated to be reversible.
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Affiliation(s)
| | | | | | | | | | - Zaher A Radi
- Pfizer Research & Development, Cambridge, Massachusetts, USA
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Aljassim FK, El-Sheikh AA, Motabagani MA. The Effect of Tamoxifen Citrate on Granulosa Cells of Ovarian Follicles in Adult Female Rats: Light Microscopic Study. J Microsc Ultrastruct 2024; 12:1-5. [PMID: 38633571 PMCID: PMC11019587 DOI: 10.4103/jmau.jmau_79_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 09/27/2021] [Accepted: 09/29/2021] [Indexed: 11/11/2022] Open
Abstract
Background Tamoxifen is a drug that has been used extensively as a chemotherapeutic agent for breast cancer. It should be taken for a long period, from few weeks up to many years, so it can induce gynecological and nongynecological complications. Aim Present study was conducted to clarify the histopathological effects of tamoxifen intake on the ovarian follicles of rats and evaluate the promising recovery after drug withdrawal. Materials and Methods Adult female albino rats (n = 24) were randomly divided into four groups. Group I: Control rats without treatment. Group II: Rats received olive oil vehicle. Group III: Rats received 5 mg/kg daily of tamoxifen dissolved in olive oil by oral administration for 4 weeks. Group IV: Rats received tamoxifen as in Group III then will be kept for another 4 weeks without treatment for recovery. Then, the rats were anaesthetized and the ovaries were removed and prepared for histological assessment by light microscope. Results The ovarian histological findings in the ovary of Group III revealed an increase in atretic ovarian follicles, appearance of cystic ovarian follicles, and cystic corpus luteum. The granulosa cells of ovarian follicles were disorganized with vacuolation of their cytoplasm, increased number of pyknotic nuclei, fragmented nuclei, and apoptotic bodies. After the withdrawal of drug, the ovarian tissue showed slight improvement with the appearance of some atretic follicles with degenerated oocyte and stromal hyperplasia. Conclusion Based on the results, tamoxifen induced marked histological changes in the ovary. If tamoxifen is mandatory for the prevention of breast cancer, frequent gynecological examination should be carried out to detect any side effects.
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Affiliation(s)
- Fatimah Khalil Aljassim
- Department of Anatomy, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Amal Ahmed El-Sheikh
- Department of Anatomy, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Mohamed A. Motabagani
- Department of Anatomy, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
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3
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Nsamou PCN, Momo ACT, Tchatat YBP, Fozin GRB, Kemka FX, Ngadjui E, Watcho P. The edible plant Amaranthus hybridus (Amaranthaceae) prevents the biochemical, histopathological and fertility impairments in colibri®-treated female rats. Toxicol Rep 2022; 9:422-431. [PMID: 35310145 PMCID: PMC8927798 DOI: 10.1016/j.toxrep.2022.03.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 02/14/2022] [Accepted: 03/04/2022] [Indexed: 11/24/2022] Open
Abstract
Colibri® a commercial formulation of Imidacloprid severely impairs the reproductive function. This study aimed at evaluating the preventive effects of Amaranthus hybridus on the reproductive toxicity of colibri® in female rats. Eighty rats (n = 10/group) were orally treated with colibri® (22.5 mg/kg) and co-administered with either aqueous or methanolic extracts of A. hybridus (55 or 110 mg/kg) within four weeks. Control animals received either distilled water (10 ml/kg), clomiphene citrate or vitamin E. Starting from day 18 of treatment till the end, half of animals in each group (n = 5) was used for the fertility test whereas the remaining rats were kept under treatment until sacrifice. Blood, ovaries, uterus and vagina were collected after sacrifice for measurement of sexual hormones, oxidative stress markers and histological assessment. Exposure of female rats to colibri® was followed by a significant reduction (p < 0.05) in the ovarian and uterine weights, LH, FSH, estradiol and progesterone levels as well as ovarian superoxide dismutase, catalase and peroxidase activities. Moreover, alteration of ovaries, uteri and vagina histology, increase in MDA concentration, decrease in fertility and parturition indices and, pup's viability were recorded. Co-administration of colibri® and plant extracts significantly (p < 0.05-0.001) prevented the above-mentioned damages through biochemical parameter regulations. These results suggest that A. hybridus exerts a preventive effect against colibri®-induced female reproductive toxicity.
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Affiliation(s)
- Prechmy Carole Ngueyong Nsamou
- Research Unit of Animal Physiology and Phytopharmacology, Faculty of Science, University of Dschang, P.O. BOX. 67, Dschang, Cameroon
| | - Aimé Césaire Tetsatsi Momo
- Research Unit of Animal Physiology and Phytopharmacology, Faculty of Science, University of Dschang, P.O. BOX. 67, Dschang, Cameroon
| | - Yannick Baudouin Petnga Tchatat
- Research Unit of Animal Physiology and Phytopharmacology, Faculty of Science, University of Dschang, P.O. BOX. 67, Dschang, Cameroon
| | - Georges Romeo Bonsou Fozin
- Research Unit of Animal Physiology and Phytopharmacology, Faculty of Science, University of Dschang, P.O. BOX. 67, Dschang, Cameroon
| | - François Xavier Kemka
- Research Unit of Animal Physiology and Phytopharmacology, Faculty of Science, University of Dschang, P.O. BOX. 67, Dschang, Cameroon
| | - Esther Ngadjui
- Research Unit of Animal Physiology and Phytopharmacology, Faculty of Science, University of Dschang, P.O. BOX. 67, Dschang, Cameroon
| | - Pierre Watcho
- Research Unit of Animal Physiology and Phytopharmacology, Faculty of Science, University of Dschang, P.O. BOX. 67, Dschang, Cameroon
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4
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Taketa Y. Luteal toxicity evaluation in rats. J Toxicol Pathol 2022; 35:7-17. [PMID: 35221491 PMCID: PMC8828616 DOI: 10.1293/tox.2021-0058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 10/27/2021] [Indexed: 11/19/2022] Open
Abstract
The corpora lutea (CL) are endocrine glands that form in the ovary after ovulation and
secrete the steroid hormone, progesterone (P4). P4 plays a critical role in estrous and
menstrual cycles, implantation, and pregnancy. The incomplete rodent estrous cycle stably
lasts 4–5 days and its morphological features can be distinguished during each estrous
cycle stage. In rat ovaries, there are two main types of CL: newly formed ones due to the
current ovulation (new CL), and CL remaining from prior estrous cycles (old CL). In the
luteal regression process, CL were almost fully regressed after four estrous cycles in
Sprague-Dawley rats. P4 secretion from CL in rodents is regulated by the balance between
synthesis and catabolism. In general, luteal toxicity should be evaluated by considering
antemortem and postmortem data. Daily vaginal smear observations provided useful
information on luteal toxicity. In histopathological examinations, not only the ovaries
and CL but also other related tissues and organs including the uterus, vagina, mammary
gland, and adrenal glands, must be carefully examined for exploring luteal changes. In
this review, histological and functional characteristics of CL in rats are summarized, and
representative luteal toxicity changes are presented for improved luteal toxicity
evaluation in preclinical toxicity research.
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Affiliation(s)
- Yoshikazu Taketa
- Department of Physical Therapy, Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata 950-3198, Japan
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5
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Elmaoğulları S, Kadan E, Anadol E, Gökçeoğlu A, Çetinkaya S, Yarım GF, Uçaktürk SA, Aycan Z. Effects of 5-Hydroxymethylfurfural on Pubertal Development of Female Wistar Rats. J Clin Res Pediatr Endocrinol 2020; 12:79-85. [PMID: 31475510 PMCID: PMC7127893 DOI: 10.4274/jcrpe.galenos.2019.2019.0080] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE 5-Hydroxymethylfurfural (HMF) is formed when sugars are heated in the presence of amino acids. HMF is naturally present in many foods. To investigate the toxic effects of HMF on the reproductive system of peripubertal rats. METHODS In the study, 24 immature female Wistar rat were divided into three groups: control (CT) fed with no HMF; low dose fed with 750 mg/kg/day of HMF and high dose (HD) groups fed with 1500 mg/kg/day of HMF. All groups received these diets for three weeks from postnatal day (PND) 21. The vaginal opening (VO) was monitored daily and euthanasia occurred on PND 44. Gonadotropin, estradiol (E2), progesterone and anti-Müllerian hormone (AMH) concentrations were measured. Reproductive organ weights and ovarian follicle counts were compared. RESULTS The HD HMF group had earlier VO. Higher mean luteinising hormone (2.9±1.2 vs 1.3±0.3 mIU/mL) and mean E2 (34.7±8.8 vs 21.2±3.9 pg/mL) and lower mean AMH (2.7±0.5 vs 4.7±0.7 ng/mL) concentrations were found in the HD compared to the CT group. The HD group also had increased number of secondary atrophic follicles. CONCLUSION These results indicate that peripubertal exposure to HMF at HD result in precocious puberty and decreased AMH levels in female Wistar rats.
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Affiliation(s)
- Selin Elmaoğulları
- University of Health Sciences Turkey, Dr. Sami Ulus Children Training and Research Hospital, Clinic of Pediatric Endocrinology, Ankara, Turkey,* Address for Correspondence: University of Health Sciences Turkey, Dr. Sami Ulus Children Training and Research Hospital, Clinic of Pediatric Endocrinology, Ankara, Turkey Phone: +90 532 580 88 62 E-mail:
| | - Elçin Kadan
- University of Health Sciences Turkey, Gülhane Training and Research Hospital, Clinic of Pathology, Ankara, Turkey
| | - Elvan Anadol
- Gazi University, Laboratory Animal Breeding and Experimental Researches Center, Ankara, Turkey
| | - Ayris Gökçeoğlu
- Ondokuz Mayıs University Faculty of Veterinary Medicine, Department of Biochemistry, Samsun, Turkey
| | - Semra Çetinkaya
- University of Health Sciences Turkey, Dr. Sami Ulus Children Training and Research Hospital, Clinic of Pediatric Endocrinology, Ankara, Turkey
| | - Gül Fatma Yarım
- Ondokuz Mayıs University Faculty of Veterinary Medicine, Department of Biochemistry, Samsun, Turkey
| | - Seyit Ahmet Uçaktürk
- University of Health Sciences Turkey, Ankara Children Diseases Hematology and Oncology Training and Research Hospital, Clinic of Pediatric Endocrinology, Ankara, Turkey
| | - Zehra Aycan
- University of Health Sciences Turkey, Dr. Sami Ulus Children Training and Research Hospital, Clinic of Pediatric Endocrinology, Ankara, Turkey
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Hu F, Schutt L, Kozlowski C, Regan K, Dybdal N, Schutten MM. Ovarian Toxicity Assessment in Histopathological Images Using Deep Learning. Toxicol Pathol 2019; 48:350-361. [DOI: 10.1177/0192623319877871] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
As ovarian toxicity is often a safety concern for cancer therapeutics, identification of ovarian pathology is important in early stages of preclinical drug development, particularly when the intended patient population include women of child-bearing potential. Microscopic evaluation by pathologists of hematoxylin and eosin (H&E)–stained tissues is the current gold standard for the assessment of organs in toxicity studies. However, digital pathology and advanced image analysis are being explored with greater frequency and broader applicability to tissue evaluations in toxicologic pathology. Our objective in this work was to develop an automated method that rapidly enumerates rat ovarian corpora lutea on standard H&E-stained slides with comparable accuracy to the gold standard assessment by a pathologist. Herein, we describe an algorithm generated by a deep learning network and tested on 5 rat toxicity studies, which included studies that both had and had not previously been diagnosed with effects on number of ovarian corpora lutea. Our algorithm could not only enumerate corpora lutea accurately in all studies but also revealed distinct trends for studies with and without reproductive toxicity. Our method could be a widely applied tool to aid analysis in general toxicity studies.
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Affiliation(s)
- Fangyao Hu
- Department of Safety Assessment, Genentech, South San Francisco, CA, USA
| | - Leah Schutt
- Department of Safety Assessment, Genentech, South San Francisco, CA, USA
| | | | | | - Noel Dybdal
- Department of Safety Assessment, Genentech, South San Francisco, CA, USA
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7
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Andrews PA, McNerney ME, DeGeorge JJ. Exposure assessments in reproductive and developmental toxicity testing: An IQ-DruSafe industry survey on current practices and experiences in support of exposure-based high dose selection. Regul Toxicol Pharmacol 2019; 107:104413. [PMID: 31229519 DOI: 10.1016/j.yrtph.2019.104413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 06/17/2019] [Accepted: 06/18/2019] [Indexed: 11/17/2022]
Abstract
The draft ICH S5(R3) guideline includes an exposure-based endpoint as an option for selecting the high dose in developmental and reproductive toxicity (DART) studies. In 2016, IQ DruSafe conducted an anonymous survey to identify industry practices and experiences related to pharmacokinetic assessments in DART studies in order to facilitate a pragmatic data-driven approach to development of an acceptable multiple of the clinical exposure to be proposed for dose selection in the guideline. Questions in the survey were designed to explore pharmacokinetic differences in pregnant versus non-pregnant animals, and to assess exposure levels attained in the absence of maternal toxicity as well as DART outcomes in animal studies associated with those exposures. Small molecule and therapeutic proteins were analyzed separately. The key findings for small molecules were: a) differences in exposures between pregnant and non-pregnant animals were generally ≤3-fold, b) Cmax or AUC exposures ≥25-fold the clinical exposure were achieved in the absence of maternal toxicity for 31% and 23% of rat and rabbit developmental toxicity studies, respectively, and c) only 3.3% (5/153) and 1.6% (2/128) of the developmental toxicity studies were positive for malformations or embryofetal lethality in rats and rabbits, respectively, that were not observed until exposure margins were ≥25-fold.
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8
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Taketa Y, Horie K, Goto T, Ohta E, Nakano-Ito K, Hayakawa K, Seki Y, Goto A, Hosokawa S. Histopathologic Characterization of Mifepristone-induced Ovarian Toxicity in Cynomolgus Monkeys. Toxicol Pathol 2018; 46:283-289. [PMID: 29558845 DOI: 10.1177/0192623318763586] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Mifepristone, which is an orally active synthetic steroid with antiprogesterone activity, is known as an ovarian toxicant. Because the available data regarding the histopathologic characteristics of ovarian toxicity in nonhuman primates are limited, the present study was undertaken in order to investigate detailed histopathologic changes accompanying mifepristone-induced ovarian toxicity and its relationship to changes in menstrual cycle and circulating sex steroid hormone. Twenty mg/kg of mifepristone was orally administered daily to 4 cynomolgus monkeys for 2 months. Mifepristone inhibited the cyclic increases in circulating estradiol-17β and progesterone levels with associated absence of menstruation. Histopathologically, the ovary in the treated animals showed follicular phase without changes in the percentage of atretic antral follicles, and reduced endometrial thickness was noted in the uterus. These changes indicated that a certain degree of antral follicle development had been retained in spite of the menstrual cycle having been arrested in mifepristone-treated animals. Our investigation suggested that it is important to perform detailed histopathologic examination of reproductive organs with precise knowledge of the characteristics of each menstrual stage to detect ovarian toxicity in nonhuman primates. Monitoring menstrual signs and circulating sex steroid hormone levels provides additional evidence for the investigation of the mechanism of ovarian toxicity.
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Affiliation(s)
- Yoshikazu Taketa
- 1 Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan
| | - Kanta Horie
- 2 Translational Medicine, Medicine Creation, Neurology Business Group, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan
| | - Tetsuya Goto
- 3 Preclinical Safety Research Unit, Tsukuba R&D Support Division, Sunplanet Co., Ltd., Tsukuba, Ibaraki, Japan
| | - Etsuko Ohta
- 1 Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan
| | - Kyoko Nakano-Ito
- 1 Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan
| | - Kazuhiro Hayakawa
- 1 Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan
| | - Yuki Seki
- 1 Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan
| | - Aya Goto
- 1 Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan
| | - Satoru Hosokawa
- 1 Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan
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9
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Stewart J. The relevance of experimental reproductive studies in safety assessment. CURRENT OPINION IN TOXICOLOGY 2017. [DOI: 10.1016/j.cotox.2017.05.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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10
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Rahman SA, Ahmad NA, Abdul Samat NH, Zahri S, Abdullah AR, Chan KL. The potential of standardized quassinoid-rich extract of Eurycoma longifolia in the regulation of the oestrous cycle of rats. Asian Pac J Trop Biomed 2017. [DOI: 10.1016/j.apjtb.2016.07.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Halpern WG, Ameri M, Bowman CJ, Elwell MR, Mirsky ML, Oliver J, Regan KS, Remick AK, Sutherland VL, Thompson KE, Tremblay C, Yoshida M, Tomlinson L. Scientific and Regulatory Policy Committee Points to Consider Review: Inclusion of Reproductive and Pathology End Points for Assessment of Reproductive and Developmental Toxicity in Pharmaceutical Drug Development. Toxicol Pathol 2016; 44:789-809. [PMID: 27235322 PMCID: PMC4979743 DOI: 10.1177/0192623316650052] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Standard components of nonclinical toxicity testing for novel pharmaceuticals include clinical and anatomic pathology, as well as separate evaluation of effects on reproduction and development to inform clinical development and labeling. General study designs in regulatory guidances do not specifically mandate use of pathology or reproductive end points across all study types; thus, inclusion and use of these end points are variable. The Scientific and Regulatory Policy Committee of the Society of Toxicologic Pathology (STP) formed a Working Group to assess the current guidelines and practices on the use of reproductive, anatomic pathology, and clinical pathology end points in general, reproductive, and developmental toxicology studies. The Working Group constructed a survey sent to pathologists and reproductive toxicologists, and responses from participating organizations were collected through the STP for evaluation by the Working Group. The regulatory context, relevant survey results, and collective experience of the Working Group are discussed and provide the basis of each assessment by study type. Overall, the current practice of including specific end points on a case-by-case basis is considered appropriate. Points to consider are summarized for inclusion of reproductive end points in general toxicity studies and for the informed use of pathology end points in reproductive and developmental toxicity studies.
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Affiliation(s)
| | | | | | | | | | | | | | - Amera K Remick
- WIL Research, a Charles River Company, Hillsborough, North Carolina, USA
| | | | | | | | - Midori Yoshida
- Food Safety Commission of Japan, Minato-ku, Tokyo, Japan
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12
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Tsubota K, Kanki M, Noto T, Nakatsuji S, Oishi Y, Matsumoto M, Nakayama H. Altered gene expression profile in ovarian follicle in rats treated with indomethacin and RU486. J Toxicol Sci 2016; 40:413-25. [PMID: 25972201 DOI: 10.2131/jts.40.413] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
It is well-known that indomethacin (the cyclooxygenase 1 & 2 inhibitor) and RU486 (or mifepristone, the progesterone receptor antagonist) block follicular rupture in rats. To characterize genetic alterations in unruptured follicles, gene expression profiles in ovarian follicle were analyzed in indomethacin- and RU486-treated female Sprague-Dawley rats. Ovaries are collected at 22:00 on the proestrus day and 10:00 on the following estrus day after a single dose of indomethacin and RU486. Histopathologically, changes depicting responses to LH surge were observed in ovaries, uteri and vagina. Total RNA was extracted from pre-ovulatory follicles or unruptured follicles collected by laser microdissection and analyzed by Genechip(®). Among genes showing statistically significant changes compared to control groups, following changes were considered relevant to induction of unruptured follicles. In indomethacin-treated rats, Wnt4 was down-regulated, suggesting effect on tissue integrity and steroid genesis. In RU486-treated rats, Adamts1, Adamts9, Edn2, Ednra, Lyve1, Plat, and Pparg were down-regulated. These changes suggest effects on proteolysis for extra cellular matrix or surrounding tissue (Adamts1 & 9, and Plat), constriction of smooth muscle surrounding follicles (Edn2, Ednra, and Pparg), follicular fluid (Lyve1), and angiogenesis (Pparg). Down-regulation of angiogenesis related genes (Angpt2, Hmox1, and Vegfa) was observed in both treatment groups. Here, we clarify genetic alterations induced by the inhibition of cyclooxygenase or progesterone receptor.
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Qin L, Du ZH, Zhu SY, Li XN, Li N, Guo JA, Li JL, Zhang Y. Atrazine triggers developmental abnormality of ovary and oviduct in quails (Coturnix Coturnix coturnix) via disruption of hypothalamo-pituitary-ovarian axis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 207:299-307. [PMID: 26432752 DOI: 10.1016/j.envpol.2015.09.044] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 09/16/2015] [Accepted: 09/20/2015] [Indexed: 06/05/2023]
Abstract
There has been a gradual increase in production and consumption of atrazine (ATR) in agriculture to meet the population rising demands. Female reproduction is necessary for growth and maintenance of population. However, ATR impact on females and particularly ovarian developmental toxicity is less clear. The aim of this study was to define the pathways by which ATR exerted toxic effects on ovarian development of ovary and hypothalamo-pituitary-ovarian (HPO) axis. Female quails were dosed by oral gavage from sexual immaturity to maturity with 0, 50, 250 and 500 mg ATR/kg/d for 45 days. ATR had no effect on mortality but depressed feed intake and growth and influenced the biochemical parameters. Notably, the arrested development of ovaries and oviducts were observed in ATR-exposed quails. The circulating concentrations of E2, P, LH and PRL were unregulated and FSH and T was downregulated in ATR-treated quails. The mRNA expression of GnRH in hypothalamo and LH in pituitary and FSH in ovary was downregulated significantly by ATR exposure and FSH and PRL in pituitary were upregulated. ATR exposure upregulated the level of P450scc, P450arom, 3β-HSD and 17β-HSD in ovary and downregulated ERβ expression in female quails. However, ATR did not change ERα expression in ovary. This study provides new insights regarding female productive toxicology of ATR exposure. Ovary and oviduct in sexually maturing females were target organs of ATR-induced developmental toxicity. We propose that ATR-induced developmental abnormality of ovary and oviduct is associated with disruption of gonadal hormone balance and HPO axis in female quails.
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Affiliation(s)
- Lei Qin
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, PR China
| | - Zheng-Hai Du
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, PR China
| | - Shi-Yong Zhu
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, PR China
| | - Xue-Nan Li
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, PR China
| | - Nan Li
- National Research Insitiute for Family Planning, Beijing, 100081, PR China
| | - Jing-Ao Guo
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, PR China
| | - Jin-Long Li
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, PR China.
| | - Ying Zhang
- School of Resources & Environment, Northeast Agricultural University, Harbin, 150030, PR China.
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14
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Picut CA, Dixon D, Simons ML, Stump DG, Parker GA, Remick AK. Postnatal ovary development in the rat: morphologic study and correlation of morphology to neuroendocrine parameters. Toxicol Pathol 2014; 43:343-53. [PMID: 25107574 DOI: 10.1177/0192623314544380] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Histopathologic examination of the immature ovary is a required end point on juvenile toxicity studies and female pubertal and thyroid function assays. To aid in this evaluation and interpretation of the immature ovary, the characteristic histologic features of rat ovary through the developmental periods are described. These histologic features are correlated with published changes in neuroendocrine profiles as the hypothalamic-pituitary-gonadal axis matures. During the neonatal stage (postnatal day [PND] 0-7), ovarian follicle development is independent of pituitary gonadotropins (luteinizing hormone [LH] or follicle-stimulating hormone [FSH]), and follicles remain preantral. Antral development of "atypical" follicles occurs in the early infantile period (PND 8-14) when the ovary becomes responsive to pituitary gonadotropins. In the late infantile period (PND 15-20), the zona pellucida appears, the hilus forms, and antral follicles mature by losing their "atypical" appearance. The juvenile stage (PND 21-32) is the stage when atresia of medullary follicles occurs corresponding to a nadir in FSH levels. In the peripubertal period (PND 33-37), atresia subsides as FSH levels rebound, and LH begins its bimodal surge pattern leading to ovulation. This report will provide pathologists with baseline morphologic and endocrinologic information to aid in identification and interpretation of xenobiotic effects in the ovary of the prepubertal rat.
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Affiliation(s)
| | - Darlene Dixon
- Molecular Pathogenesis Group, National Toxicology Program (NTP) Laboratory, Division of the NTP, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
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Sato J, Hashimoto S, Doi T, Yamada N, Tsuchitani M. Histological characteristics of the regression of corpora lutea in wistar hannover rats: the comparisons with sprague-dawley rats. J Toxicol Pathol 2014; 27:107-13. [PMID: 25352711 PMCID: PMC4110934 DOI: 10.1293/tox.2013-0054] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 01/06/2014] [Indexed: 11/29/2022] Open
Abstract
We examined the ovaries of 44 Wistar Hannover (RccHanTM:WIST) (WH) and 30 Sprague-Dawley (SD) rats at 32-weeks of age to determine whether the ovarian structure and formation/regression of the corpora lutea (CLs) differ between the two strains. The average ovary weight was higher in WH rats. The average number of all CLs, including currently formed and previously formed CLs, was higher in WH rats in all cycles; however, no appreciable difference was detected in the number of newly or currently formed CLs between the two strains. CLs regression characterized by degeneration and necrosis of luteal cells began to appear in diestrus in both strains; however, the distribution of degenerated/necrotic cells in CLs differed. Necrotic cells were scattered in SD rats but were focally observed in the center of the CL in WH rats. The reduction in size of previously formed CLs accompanied by regression started about 2 or more stages later in WH rats than in those of SD rats. In conclusion, the higher number of CLs in WH rats is considered to be due to slow CL regression compared with in SD rats.
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Affiliation(s)
- Junko Sato
- Pathology Department, Kashima Laboratory, Nonclinical Research Center, LSI Medience Corporation, 14-1 Sunayama, Kamisu, Ibaraki 314-0255, Japan
| | - Satomi Hashimoto
- Pathology Department, Kashima Laboratory, Nonclinical Research Center, LSI Medience Corporation, 14-1 Sunayama, Kamisu, Ibaraki 314-0255, Japan
| | - Takuya Doi
- Pathology Department, Kashima Laboratory, Nonclinical Research Center, LSI Medience Corporation, 14-1 Sunayama, Kamisu, Ibaraki 314-0255, Japan
| | - Naoaki Yamada
- Pathology Department, Kashima Laboratory, Nonclinical Research Center, LSI Medience Corporation, 14-1 Sunayama, Kamisu, Ibaraki 314-0255, Japan
| | - Minoru Tsuchitani
- Pathology Department, Kashima Laboratory, Nonclinical Research Center, LSI Medience Corporation, 14-1 Sunayama, Kamisu, Ibaraki 314-0255, Japan
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Dixon D, Alison R, Bach U, Colman K, Foley GL, Harleman JH, Haworth R, Herbert R, Heuser A, Long G, Mirsky M, Regan K, Van Esch E, Westwood FR, Vidal J, Yoshida M. Nonproliferative and proliferative lesions of the rat and mouse female reproductive system. J Toxicol Pathol 2014; 27:1S-107S. [PMID: 25516636 PMCID: PMC4253081 DOI: 10.1293/tox.27.1s] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) Project (www.toxpath.org/inhand.asp) is a joint initiative of the Societies of Toxicological Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP) and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying microscopic lesions observed in the female reproductive tract of laboratory rats and mice, with color photomicrographs illustrating examples of some lesions. The standardized nomenclature presented in this document is also available electronically on the internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous and aging lesions as well as lesions induced by exposure to test materials. There is also a section on normal cyclical changes observed in the ovary, uterus, cervix and vagina to compare normal physiological changes with pathological lesions. A widely accepted and utilized international harmonization of nomenclature for female reproductive tract lesions in laboratory animals will decrease confusion among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists.
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Affiliation(s)
- Darlene Dixon
- National Institute of Environmental Health Sciences, National
Toxicology Program, Research Triangle Park, North Carolina, USA
| | - Roger Alison
- Roger Alison Ltd, Pathology Consultancy Services, Caerfyrddin
Fach, Cilcennin, Lampeter, SA48 8RN, United Kingdom
| | - Ute Bach
- Bayer Pharma AG, Wuppertal, Germany
| | - Karyn Colman
- Novartis Institute for Biomedical Research, Novartis, East
Hanover, New Jersey, USA
| | | | | | - Richard Haworth
- GlaxoSmithKline R&D, Park Road, Ware, Hertfordshire, SG12
ODP, United Kingdom
| | - Ronald Herbert
- National Institute of Environmental Health Sciences, National
Toxicology Program, Research Triangle Park, North Carolina, USA
| | - Anke Heuser
- Roche Pharma Research and Early Development, Roche Innovation
Center Basel, Grenzacher Strasse 124, 4070 Basel, Switzerland
| | - Gerald Long
- Experimental Pathology Laboratories, Indianapolis, Indiana,
USA
| | - Michael Mirsky
- Pfizer Worldwide Research and Development, Groton,
Connecticut, USA
| | | | - Eric Van Esch
- InSight Pathology BV, Chopinlaan 6, Oss, The
Netherlands
| | | | - Justin Vidal
- GlaxoSmithKline, King of Prussia, Pennsylvania, USA
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17
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Evaluating the male and female reproductive toxicity of high-boiling petroleum substances. Regul Toxicol Pharmacol 2013; 67:S60-74. [DOI: 10.1016/j.yrtph.2013.04.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 04/12/2013] [Accepted: 04/17/2013] [Indexed: 11/17/2022]
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18
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Ohno Y. ICH discussion on pharmacokinetics and toxicokinetics and contributors. Drug Metab Pharmacokinet 2013; 28:379-82. [PMID: 24162438 DOI: 10.2133/dmpk.dmpk-13-pf-905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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19
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Toxicology and pathology of female reproductive tract. Cell Biol Toxicol 2013; 29:131-41. [DOI: 10.1007/s10565-013-9244-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 04/04/2013] [Indexed: 10/26/2022]
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20
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Bass R, Ohno Y, Ulbrich B. Why and How Did Reproduction Toxicity Testing Make Its Early Entry into and Rapid Success in ICH? ACTA ACUST UNITED AC 2013. [DOI: 10.1007/978-1-4614-5950-7_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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21
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Taketa Y, Inoue K, Takahashi M, Yamate J, Yoshida M. Differential morphological effects in rat corpora lutea among ethylene glycol monomethyl ether, atrazine, and bromocriptine. Toxicol Pathol 2012; 41:736-43. [PMID: 23076038 DOI: 10.1177/0192623312464305] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Ethylene glycol monomethyl ether (EGME) or atrazine induces luteal cell hypertrophy in rats. Our previous study suggested that EGME stimulates both new and old corpora lutea (CL), while atrazine stimulates new CL. Bromocriptine (BRC) is known to suppress the luteolysis in rats. This study investigated the light- and electron-microscopic luteal changes induced by EGME, atrazine, or BRC. Female rats were treated with EGME (300 mg/kg/day), BRC (2 mg/kg/day), EGME and BRC (EGME + BRC), or atrazine (300 mg/kg/day) for 7 days. Luteal cell hypertrophy induced by EGME, EGME + BRC, and atrazine was subclassified into the following two types: CL hypertrophy, vacuolated type (CL-V) characterized by intracytoplasmic fine vacuoles, and CL hypertrophy, eosinophilic type (CL-E) characterized by eosinophilic and abundant cytoplasm. The proportions of CL-V and CL-E were different among the treatments. BRC-treated old CL showed lower proportion of endothelial cells and fibroblasts than normal old CL. Ultrastructural observation revealed that the luteal cells of CL-V contained abundant lipid droplets, whereas those of CL-E in EGME and EGME + BRC groups showed uniformly well-developed smooth endoplasmic reticulum. No clear ultrastructural difference was observed between the control CL and atrazine-treated CL-E. These results indicate that EGME, atrazine, and BRC have differential luteal morphological effects.
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Affiliation(s)
- Yoshikazu Taketa
- Division of Pathology, National Institute of Health Sciences, Tokyo 156-8501, Japan.
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22
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Aulmann W. Assessment of reproductive toxicity under REACH. Regul Toxicol Pharmacol 2012; 63:286-90. [PMID: 22475931 DOI: 10.1016/j.yrtph.2012.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 02/29/2012] [Accepted: 03/06/2012] [Indexed: 10/28/2022]
Abstract
The European REACH regulation requires the evaluation of reproductive toxicity in screening tests according to OECD TG 421 and 422 for substances above the tonnage level of 10 tons/year. The overall aim of this paper is to increase flexibility in combination with a reduced number of experimental animals. Therefore, in contrast to the existing approach the registrant should have the possibility to file a dossier for a substance at the level of 10 tons/year and above also on the basis of data from a developmental toxicity study (OECD TG 414) plus a full-scale subacute toxicity study (OECD TG 407 according to the 1995 protocol). The proposed new test strategy takes into account overall considerations of duty of care and animal welfare. It enables an assessment of developmental toxicity on a definitive instead of a screening level. Registrants should be allowed to select between these two options, either the existing approach (OECD TG 421/407 and alternatively TG 422) or the approach proposed in this paper (OECD TG 407 plus TG 414).
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Affiliation(s)
- Walter Aulmann
- Ecolab Deutschland GmbH, Reisholzer Werftstr. 38-42, 40554 Düsseldorf, Germany.
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Tsubota K, Kanki M, Noto T, Shiraki K, Takeuchi A, Nakatsuji S, Seki J, Oishi Y, Matsumoto M, Nakayama H. Transitional gene expression profiling in ovarian follicle during ovulation in normal-cycle rats. Toxicol Pathol 2011; 39:641-52. [PMID: 21551027 DOI: 10.1177/0192623311406932] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Evaluation of ovarian toxicity requires an understanding of the physiological changes related to the estrous cycle in the ovary. The authors investigated the transitional gene expression profile of ovulatory follicles in rats that show normal estrous cyclicity. Ovaries were collected at 10:00 and 22:00 on the proestrus day and at 10:00 on the estrus day. Ovarian follicles or early corpora lutea were isolated using laser microdissection, and extracted total RNA was analyzed using microarray technology. Clustering analysis revealed four different expression patterns: transient up- or down-regulation only at 22:00 on the proestrus day (pattern 1), up- or down-regulation only at 10:00 on the estrus day (pattern 2), continuous increase at 22:00 on the proestrus day and at 10:00 on the estrus day (pattern 3), and up- or down-regulation at 22:00 on the proestrus day and level maintenance at 10:00 on the estrus day (pattern 4). In addition, these probe sets were functionally categorized in each pattern using the Ingenuity Pathways Analysis database. These data will aid in understanding the physiology of ovulation and may be useful in assessing ovarian toxicity and its mechanism, such as in investigations of chemical-induced ovulatory impairment.
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Affiliation(s)
- Kenjiro Tsubota
- Toxicologic Pathology, Drug Safety Research Laboratories, Astellas Pharma Inc., Osaka, Japan.
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Mirsky ML, Sivaraman L, Houle C, Potter DM, Chapin RE, Cappon GD. Histologic and cytologic detection of endocrine and reproductive tract effects of exemestane in female rats treated for up to twenty-eight days. Toxicol Pathol 2011; 39:589-605. [PMID: 21540174 DOI: 10.1177/0192623311402220] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The objective of this study was to determine the shortest period of time necessary to detect histologic evidence of estrous cycle disruption in Sprague-Dawley rats treated for up to 28 days with the aromatase inhibitor exemestane at 1,000 mg/kg. Rats were evaluated on day 5, 8, 15, or 29. Vaginal mucification, uterine and cervical epithelial atrophy, uterine luminal epithelial vacuolation, decreased uterine granulocytes, and hypertrophy/hyperplasia of mammary ducts and alveoli were noted by day 5 and persisted throughout the study. From day 8 to day 29, absence of recent basophilic corpora lutea, increased atresia of antral follicles, interstitial cell hyperplasia, and increased luteinized follicles were present in the ovaries of treated rats. Vaginal smears detected persistent diestrus, confirming estrous cycle disruption between days 5 and 8. Ovary and uterine weights were largely unaffected. Serum hormone levels were not useful due to the study design employed. Other effects of exemestane included decreased adrenal weights and decreased cell size in both the adrenal zona fasciculata and the pituitary pars distalis. While early histologic changes were evident on day 5, only after 8 days of treatment were findings considered sufficient to clearly identify exemestane-induced estrous cycle disruption using microscopy alone.
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Affiliation(s)
- Michael L Mirsky
- Pfizer Global Research and Development, Groton, Connecticut 06340, USA.
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Taketa Y, Yoshida M, Inoue K, Takahashi M, Sakamoto Y, Watanabe G, Taya K, Yamate J, Nishikawa A. Differential Stimulation Pathways of Progesterone Secretion from Newly Formed Corpora Lutea in Rats Treated with Ethylene Glycol Monomethyl Ether, Sulpiride, or Atrazine. Toxicol Sci 2011; 121:267-78. [DOI: 10.1093/toxsci/kfr062] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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26
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Lerman SA, Hew KW, Stewart J, Stump DG, Wise LD. The nonclinical fertility study design for pharmaceuticals. ACTA ACUST UNITED AC 2009; 86:429-36. [DOI: 10.1002/bdrb.20221] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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27
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Yoshida M, Sanbuissyo A, Hisada S, Takahashi M, Ohno Y, Nishikawa A. Morphological characterization of the ovary under normal cycling in rats and its viewpoints of ovarian toxicity detection. J Toxicol Sci 2009; 34 Suppl 1:SP189-97. [PMID: 19265285 DOI: 10.2131/jts.34.s189] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Identification of ovarian toxicity is very important for safety assessment of drugs and other environmental chemicals. The detection of interference with ovarian function is very hard without a thorough understanding of the normal ovarian morphology based on reproductive physiology. The focus of the present study was therefore a practical analysis in each stage of the estrous cycles using ovaries obtained from 143 rats demonstrating normal cycling. Transversely dissected maximum areas in the ovaries were examined microscopically for the two major features, follicles and corpora lutea (CL). Classification of growing follicles was in reference to Pedersen and Peters (1968), and functionally divided into follicular stimulating hormone (FSH)-independent and dependent categories. The former, small and medium-sized follicles, respectively primordial/primary and preantral follicles, could be readily detected by immunohistochemical staining for proliferating cell nuclear antigen (PCNA). The large antral and Graafian follicles and large sized atretic follicles showed sequential changes depending on the estrous cycle stage. CL could be divided into currently and previously formed examples. Currently formed CL underwent remarkable changes in their appearance with the cycle, reflecting ovulation and progesterone production. Thus morphological analysis that is synchronized the large antral follicle changes with recently formed CL ones allows the ovary to be classified into the each estrous cycle stage. Morphological deviation from any synchronized combination provides a first pointer of ovarian toxicity. PCNA immunohistochemical staining is also useful to detect small follicles.
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Affiliation(s)
- Midori Yoshida
- Division of Pathology, Biology Safety Research Center, National Institute of Health Sciences, Tokyo, Japan.
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