1
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Shakeel M, Yoon M. Functions of somatic cells for spermatogenesis in
stallions. JOURNAL OF ANIMAL SCIENCE AND TECHNOLOGY 2022; 64:654-670. [PMID: 35969700 PMCID: PMC9353347 DOI: 10.5187/jast.2022.e57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/20/2022]
Abstract
Spermatogenesis and testis development are highly structured physiological
processes responsible for post-pubertal fertility in stallions. Spermatogenesis
comprises spermatocytogenesis, meiosis, and spermiogenesis. Although germ cell
degeneration is a continuous process, its effects are more pronounced during
spermatocytogenesis and meiosis. The productivity and efficiency of
spermatogenesis are directly linked to pubertal development, degenerated germ
cell populations, aging, nutrition, and season of the year in stallions. The
multiplex interplay of germ cells with somatic cells, endocrine and paracrine
factors, growth factors, and signaling molecules contributes to the regulation
of spermatogenesis. A cell-to-cell communication within the testes of these
factors is a fundamental requirement of normal spermatogenesis. A noteworthy
development has been made recently on discovering the effects of different
somatic cells including Leydig, Sertoli, and peritubular myoid cells on
manipulation the fate of spermatogonial stem cells. In this review, we discuss
the self-renewal, differentiation, and apoptotic roles of somatic cells and the
relationship between somatic and germ cells during normal spermatogenesis. We
also summarize the roles of different growth factors, their
paracrine/endocrine/autocrine pathways, and the different cytokines associated
with spermatogenesis. Furthermore, we highlight important matters for further
studies on the regulation of spermatogenesis. This review presents an insight
into the mechanism of spermatogenesis, and helpful in developing better
understanding of the functions of somatic cells, particularly in stallions and
would offer new research goals for developing curative techniques to address
infertility/subfertility in stallions.
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Affiliation(s)
- Muhammad Shakeel
- Department of Animal Science and
Biotechnology, Kyungpook National University, Sangju 37224,
Korea
- Department of Clinical Studies, Faculty of
Veterinary and Animal Sciences, Pir Mehr Ali Shah, Arid Agriculture
University, Rawalpindi 44000, Pakistan
| | - Minjung Yoon
- Department of Animal Science and
Biotechnology, Kyungpook National University, Sangju 37224,
Korea
- Department of Horse, Companion and Wild
Animal Science, Kyungpook National University, Sangju 37224,
Korea
- Reseach Center for Horse Industry,
Kyungpook National University, Sangju 37224, Korea
- Corresponding author: Minjung Yoon,
Department of Animal Science and Biotechnology, Kyungpook National University,
Sangju 37224, Korea. Tel: +82-54-530-1233, E-mail:
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2
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Ball BA, Davolli GM, Esteller-Vico A, Fleming BO, Wynn MAA, Conley AJ. Inhibin-A and Inhibin-B in stallions: Seasonal changes and changes after down-regulation of the hypothalamic-pituitary-gonadal axis. Theriogenology 2018; 123:108-115. [PMID: 30296651 DOI: 10.1016/j.theriogenology.2018.09.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 09/17/2018] [Accepted: 09/26/2018] [Indexed: 11/26/2022]
Abstract
The biological function of inhibin is mediated by two heterodimers, inhibin-A and inhibin-B. The relative importance of inhibin-A and -B in male reproductive function varies considerably across species with inhibin-B predominating in many species, whereas inhibin-A appears relatively more important in rams. Research reported to date in stallions has examined total or immunoreactive (ir) inhibin which does not distinguish the two heterodimers. Therefore, the objective of this study was to characterize changes in inhibin-A and inhibin-B concentrations in stallions: 1) across season for a period of one year, and 2) after downregulation of the hypothalamic-pituitary-gonadal (HPG) axis. In Study one, serum samples were obtained monthly from five stallions for a period of one year. Serum concentrations of inhibin-A, inhibin-B, testosterone and estrone sulfate were determined by ELISA. In Study two, stallions were treated with the GnRH antagonist, acyline (n = 4; 330 mg/kg acyline IM) or vehicle control (n = 4; vehicle alone) every five days for 50 days. Plasma concentrations of inhibin-A and -B were determined by ELISA at Days 0, 6, 12, 22, 37, 59, 80, 87 and 104 after initiation of acyline treatment. Testis volume was determined by ultrasonography at weekly intervals. In Study 1, both inhibin-A and inhibin-B showed seasonal changes in concentration with highest concentrations in increasing day length and lowest concentrations in short day lengths. Inhibin-B (overall mean 107.8 ± 4.1 pg/mL) was present at 4.7-fold higher concentrations in serum than inhibin-A (overall mean 23.0 ± 0.7 pg/mL). In Study 2, plasma concentrations of inhibin-B but not inhibin-A were significantly downregulated by administration of the GnRH antagonist, acyline. When the HPG axis was downregulated by acyline, testis volume was strongly correlated with inhibin-B (r = 0.73; P < 0.05) but not inhibin-A (r = 0.22; P = 0.20). In summary, inhibin-B appears to be the predominant form of inhibin in the stallion which undergoes seasonal regulation along with other reproductive parameters and is co-regulated with other endocrine parameters of the HPG axis.
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Affiliation(s)
- B A Ball
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, 40546, USA.
| | - G M Davolli
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, 40546, USA
| | - A Esteller-Vico
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, 40546, USA
| | - B O Fleming
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, 40546, USA
| | - M A A Wynn
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, 40546, USA
| | - A J Conley
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA, 95616, USA
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3
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Sakase M, Kitagawa K, Kibushi M, Kawate N, Weerakoon WWPN, Hannan MA, Kohama N, Tamada H. Relationships of plasma insulin-like peptide 3, testosterone, inhibin, and insulin-like growth factor-I concentrations with scrotal circumference and testicular weight in Japanese Black beef bull calves. J Reprod Dev 2018; 64:401-407. [PMID: 29984734 PMCID: PMC6189565 DOI: 10.1262/jrd.2018-034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
This study was conducted to clarify the relationships of plasma concentrations of insulin-like peptide 3 (INSL3), testosterone, inhibin, and insulin-like growth factor-I (IGF-I) with scrotal circumference and testicular weight in Japanese Black beef bull calves (n = 20), from birth to pre-puberty. Monthly blood sampling (0 to 7 months) and scrotal circumference measurements (0 to 7 months) were performed. Testicular weight was recorded immediately after castration at 7 months. Plasma INSL3, testosterone, inhibin, and IGF-I concentrations were measured either by enzyme immunoassay or time-resolved fluorescence immunoassay. The correlation coefficients of these hormonal concentrations with scrotal circumference were significant (P < 0.0001) and it was higher for INSL3 (r = 0.647) than for testosterone (r = 0.597), IGF-I (r = 0.400), and inhibin (r = –0.453). Calves with heavier testes (> 60 g) at castration (7 months) had higher (P < 0.05) plasma INSL3 (from 3 to 7 months) and inhibin (from 1 to 4 months) concentrations than those with lighter testes (< 60 g). The calves with heavier testes at castration had larger (P < 0.05) scrotal circumference than those with lighter testes from 3 to 7 months. In conclusion, blood INSL3 concentrations may be the best functional indicator among the hormones analyzed for determining total testicular volume during pre-puberty in bull calves. In addition, inhibin and INSL3 concentrations in early calfhood may be functional predictors for testicular weight at pre-puberty.
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Affiliation(s)
- Mitsuhiro Sakase
- Hokubu Agricultural Institute, Hyogo Prefectural Technology Center for Agriculture, Forestry and Fisheries, Hyogo 669-5254, Japan
| | - Keita Kitagawa
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Masahiko Kibushi
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan.,Asago Animal Hygiene Institute of Hyogo Prefecture, Hyogo 669-5243, Japan
| | - Noritoshi Kawate
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - W W P N Weerakoon
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - M A Hannan
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Namiko Kohama
- Hokubu Agricultural Institute, Hyogo Prefectural Technology Center for Agriculture, Forestry and Fisheries, Hyogo 669-5254, Japan
| | - Hiromichi Tamada
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
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4
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Weerakoon WWPN, Sakase M, Kawate N, Hannan MA, Kohama N, Tamada H. Plasma IGF-I, INSL3, testosterone, inhibin concentrations and scrotal circumferences surrounding puberty in Japanese Black beef bulls with normal and abnormal semen. Theriogenology 2018; 114:54-62. [PMID: 29597124 DOI: 10.1016/j.theriogenology.2018.03.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 03/09/2018] [Accepted: 03/10/2018] [Indexed: 10/17/2022]
Abstract
The relationships between semen abnormalities and peripheral concentrations of testicular and metabolic hormones in beef bulls are unclear. Here we compared plasma insulin-like growth factor I (IGF-I), insulin-like peptide 3 (INSL3), testosterone, inhibin concentrations, and scrotal circumferences surrounding puberty in Japanese Black beef bulls (n = 66) with normal or abnormal semen. We collected blood samples and measured scrotal circumferences monthly from 4 to 24 months of age. Semen was collected weekly from 12 months until at least 18 months of age. Fresh semen was evaluated for semen volume, sperm motility, concentrations, and morphological defects. The normal fresh semen was frozen by a standard method and examined for post-thaw sperm motility and fertility. Bulls were classified as having either normal post-thaw semen (n = 45) or abnormal semen (n = 21, when at least one of the above test items was abnormal for 6 months). Abnormal semen was classified into abnormal fresh or low-fertility post-thaw which evaluated for rates of transferable embryos. The abnormal fresh was categorized as having sperm morphological defects, low motility, and morphological defects plus low motility. Scrotal circumferences were smaller for the abnormal-semen group vs. the normal-semen group at 20 and 24 months (p < 0.05). Plasma IGF-I, INSL3, and inhibin concentrations in the abnormal-semen group were lower than those of the normal-semen group (p < 0.05) surrounding puberty (4-6, 8, 18-22, and 24 months for IGF-I; 6, 9, 11-14, 17, and 20-21 months for INSL3; 5, 8-13, 16, 17, 19, and 20 months for inhibin). The plasma testosterone concentrations were lower in the abnormal-semen bulls vs. normal-semen bulls only at 22 months (p < 0.05). Analyses of the classified abnormal semen showed lower plasma INSL3 concentrations for morphological defects plus low motility in fresh semen (p < 0.05) and lower IGF-I and inhibin concentrations for low-fertility post-thaw semen (p < 0.05) compared to the normal semen. Our results suggest that reduced secretions of IGF-I, INSL3, and inhibin surrounding puberty may be associated with semen aberration in beef bulls. Notably, the combined sperm abnormality of morphological defects and low motility in fresh semen could involve lowered INSL3, whereas the low-fertility post-thaw semen might be related to decreases of IGF-I and/or inhibin. Pre-puberty blood IGF-I, INSL3 and inhibin concentrations could be used as indicators to predict aberrant semen in beef bulls.
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Affiliation(s)
- W W P N Weerakoon
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan
| | - M Sakase
- Northern Center of Agriculture Technology, General Technological Center of Hyogo Prefecture for Agriculture, Forest and Fishery, Asago, Hyogo, Japan
| | - N Kawate
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan.
| | - M A Hannan
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan
| | - N Kohama
- Northern Center of Agriculture Technology, General Technological Center of Hyogo Prefecture for Agriculture, Forest and Fishery, Asago, Hyogo, Japan
| | - H Tamada
- Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan
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5
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Chaichanathong S, Taya K, Watanabe G, Nagaoka K, Wajjwalku W, Sudsukh A, Thongtip N. Immunohistochemical localization of inhibin/activin subunits in adult Asian elephant (Elephas maximus) testes. J Vet Med Sci 2018; 80:549-552. [PMID: 29375089 PMCID: PMC5880841 DOI: 10.1292/jvms.17-0531] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Immunolocalization of inhibin-α and inhibin/activin βA and βB subunits in the testes of Asian elephant was determined. Testicular sections were immunostained with polyclonal antisera against inhibin subunit-α and
inhibin/activin βA and βB using the avidin-biotin-peroxidase complex method. Positive immunostaining against inhibin-α subunit was strongly present in Sertoli cells, and positive immunostaining for the inhibin/activin βA
and βB subunits was observed in both Sertoli and Leydig cells. These results indicated that while Sertoli cells are the predominant source of inhibin and activin secretions in the testes of adult male Asian elephant,
Leydig cells are a source of activin but not inhibin.
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Affiliation(s)
- Sirinart Chaichanathong
- Center for Agricultural Biotechnology, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand.,Center of Excellence on Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok 10900, Thailand.,Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen campus, Nakhon Pathom 73140, Thailand
| | - Kasuyoshi Taya
- Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan
| | - Gen Watanabe
- Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.,Cooperative Division of Veterinary Science, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan
| | - Kentaro Nagaoka
- Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.,Cooperative Division of Veterinary Science, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan
| | - Worawidh Wajjwalku
- Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen campus, Nakhon Pathom 73140, Thailand
| | - Apichaya Sudsukh
- Department of Obstetrics, Gynecology and Reproduction, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Nikorn Thongtip
- Center for Agricultural Biotechnology, Kasetsart University, Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand.,Department of Large Animal and Wildlife Clinical Science, Faculty of Veterinary Medicine, Kasetsart University, Nakhon Pathom 73140, Thailand
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6
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Katsumata E, Jaroenporn S, Ueda Y, Arai K, Katsumata H, Watanabe G, Taya K. Circulating gonadotropins and testicular hormones during sexual maturation and annual changes in male bottlenose dolphins (Tursiops truncatus). J Vet Med Sci 2017; 79:1899-1905. [PMID: 28993599 PMCID: PMC5709572 DOI: 10.1292/jvms.16-0544] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To reveal the reproductive biology in male bottlenose dolphins (Tursiops truncatus), circulating gonadotropins (follicle stimulating hormone [FSH] and luteinizing hormone [LH]) and testicular hormones
(testosterone and inhibin) were monitored for 8−12 years in 2 captive bottlenose dolphins (Mars and Regulus). During the study period, Mars was undergoing sexual maturation, whereas Regulus was already mature at the beginning of
the study. Assuming that Mars had reached sexual maturity when the significant increase in circulating testosterone levels was observed, serum concentration of inhibin was higher in the sexually immature stage than in the mature
stage, whereas the serum concentration of FSH was higher in the sexually mature stage than in the immature stage. No difference was observed in the LH levels between pre- and post-sexual maturation. There was a significant
increase in serum concentration of testosterone during spring in both animals. These results suggest that the mechanism responsible for regulating FSH secretion by inhibin functions during the sexually immature stage in this
species.
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Affiliation(s)
- Etsuko Katsumata
- Kamogawa Sea World, 1464-18 Higashi-cho, Kamogawa, Chiba 296-0041, Japan
| | - Sukanya Jaroenporn
- Primate Research Unit, Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Yoko Ueda
- Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan
| | - Kazutoshi Arai
- Kamogawa Sea World, 1464-18 Higashi-cho, Kamogawa, Chiba 296-0041, Japan
| | - Hiroshi Katsumata
- Kamogawa Sea World, 1464-18 Higashi-cho, Kamogawa, Chiba 296-0041, Japan
| | - Gen Watanabe
- Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.,United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan
| | - Kazuyoshi Taya
- Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.,International Marine Biological Research Institute, Kamogawa Sea World, 1464-18 Higashi-cho, Kamogawa, Chiba 296-0041, Japan
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7
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Kanamori Y, Sugiyama M, Hashimoto O, Murakami M, Matsui T, Funaba M. Regulation of hepcidin expression by inflammation-induced activin B. Sci Rep 2016; 6:38702. [PMID: 27922109 PMCID: PMC5138601 DOI: 10.1038/srep38702] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 11/14/2016] [Indexed: 02/08/2023] Open
Abstract
Activin B is induced in response to inflammation in the liver and enhances hepcidin expression, but the source of activin B and the molecular mechanism underlying hepcidin induction are not clear yet. Lipopolysaccharide (LPS)-induced inflammation induced inhibin βB but not inhibin α or inhibin βA expression in the liver, implicating activin B induction. Immunoreactive inhibin βB was detected in endothelial cells and Kupffer cells in LPS-treated liver. Activin B, but not activin A or activin AB, directly increased hepcidin expression. Activin B induced phosphorylation and activation of Smad1/5/8, the BMP-regulated (BR)-Smads. The stimulation of hepcidin transcription by activin B was mediated by ALK2 and ActRIIA, receptors for the TGF-β family. Unexpectedly, activin B-induced hepcidin expression and BR-Smad phosphorylation were resistant to the effects of LDN-193189, an ALK2/3/6 inhibitor. ALK2 and ActRIIA complex formation in response to activin B may prevent the approach of LDN-193189 to ALK2 to inhibit its activity. Activin B also induced phosphorylation of Smad2/3, the TGF-β/activin-regulated (AR)-Smad, and increased expression of connective tissue growth factor, a gene related to liver fibrogenesis, through ALK4 and ActRIIA/B. Activin B-induced activation of the BR-Smad pathway was also detected in non-liver-derived cells. The present study reveals the broad signaling of activin B, which is induced in non-parenchymal cells in response to hepatic inflammation, in hepatocytes.
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Affiliation(s)
- Yohei Kanamori
- Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Makoto Sugiyama
- Laboratory of Veterinary Anatomy, Kitasato University School of Veterinary Medicine, Towada 034-8628, Japan
| | - Osamu Hashimoto
- Laboratory of Experimental Animal Science, Kitasato University School of Veterinary Medicine, Towada 034-8628, Japan
| | - Masaru Murakami
- Laboratory of Molecular Biology, Azabu University School of Veterinary Medicine, Sagamihara 252-5201, Japan
| | - Tohru Matsui
- Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Masayuki Funaba
- Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
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8
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Banco B, Grilli G, Giudice C, Marques AT, Cotti Cometti S, Visigalli G, Grieco V. Immunophenotyping of Rabbit Testicular Germ and Sertoli Cells Across Maturational Stages. J Histochem Cytochem 2016; 64:715-726. [PMID: 27680667 DOI: 10.1369/0022155416669918] [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] [Indexed: 11/22/2022] Open
Abstract
During testicular maturation, both Sertoli cells (SCs) and germ cells (GCs) switch from an immature to a mature immunophenotype. The reexpression of markers of immaturity in adults has been reported in cancer and in other testicular pathologies, in men as well as in animal species. Naturally affected with testicular cancer, rabbits have long been used in human reproductive research, but reports on the expression of testicular cell markers in this species are few and data about the immunophenotype of normal postnatal SCs and GCs are lacking. The aim of this study was to investigate the immunophenotype of SCs and GCs in the rabbit, from neonatal to adult age, using the antibodies anti-Müllerian hormone (AMH), vimentin (VIM), CKAE1/AE3 (cytokeratins [CKs]), desmin (DES), inhibin alpha (INH-α), placental alkaline phosphatase (PLAP), and periodic acid-Schiff (PAS) staining. In SCs, VIM was constantly expressed, and AMH and CKs expression was limited to neonatal and prepubertal age, whereas DES, INH-α, PLAP, and PAS were constantly negative. GCs were negatively stained for PLAP, PAS, and for the other markers. Results revealed analogies with human testicular immunophenotype, suggesting that rabbits could represent a potential experimental model for the study of human testicular pathology.
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Affiliation(s)
- B Banco
- Department of Veterinary Medicine, Università degli Studi di Milano, Milano, Italy (BB, GG, CG, ATM, SCC, VG)
| | - G Grilli
- Department of Veterinary Medicine, Università degli Studi di Milano, Milano, Italy (BB, GG, CG, ATM, SCC, VG)
| | - C Giudice
- Department of Veterinary Medicine, Università degli Studi di Milano, Milano, Italy (BB, GG, CG, ATM, SCC, VG)
| | - A Tomas Marques
- Department of Veterinary Medicine, Università degli Studi di Milano, Milano, Italy (BB, GG, CG, ATM, SCC, VG)
| | - S Cotti Cometti
- Department of Veterinary Medicine, Università degli Studi di Milano, Milano, Italy (BB, GG, CG, ATM, SCC, VG)
| | - G Visigalli
- Clinica Veterinaria Liana Blu, Varedo (MI), Italy (GV)
| | - V Grieco
- Department of Veterinary Medicine, Università degli Studi di Milano, Milano, Italy (BB, GG, CG, ATM, SCC, VG)
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9
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Luca G, Mancuso F, Calvitti M, Arato I, Falabella G, Bufalari A, De Monte V, Tresoldi E, Nastruzzi C, Basta G, Fallarino F, Lilli C, Bellucci C, Baroni T, Aglietti MC, Giovagnoli S, Cameron DF, Bodo M, Calafiore R. Long-term stability, functional competence, and safety of microencapsulated specific pathogen-free neonatal porcine Sertoli cells: a potential product for cell transplant therapy. Xenotransplantation 2015; 22:273-83. [PMID: 26134468 DOI: 10.1111/xen.12175] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 06/04/2015] [Indexed: 01/13/2023]
Abstract
BACKGROUND Porcine Sertoli cells (pSCs) have been employed for cell therapy in pre-clinical studies for several chronic/immune diseases as they deliver molecules associated with trophic and anti-inflammatory effects. To be employed for human xenografts, pSCs products need to comply with safety and stability. To fulfill such requirements, we employed a microencapsulation technology to increase pre-transplant storage stability of specific pathogen-free pSCs (SPF-pSCs) and evaluated the in vivo long-term viability and safety of grafts. METHODS Specific pathogen free neonatal pigs underwent testis excision under sterility. pSCs were isolated, characterized by immunofluorescence (IF) and cytofluorimetric analysis (CA) and examined in terms of viability and function [namely, production of anti-müllerian hormone (AMH), inhibin B, and transforming growth factor beta-1 (TFGβ-1)]. After microencapsulation in barium alginate microcapsules (Ba-MC), long-term SPF-pSCs (Ba-MCpSCs) viability and barium concentrations were evaluated at 1, 24 throughout 40 h to establish pre-transplant storage conditions. RESULTS The purity of isolated pSCs was about 95% with negligible contaminating cells. Cultured pSCs monolayers, both prior to and after microencapsulation, maintained high function and full viability up to 24 h of storage. At 40 h post-encapsulation, pSCs viability decreased to 80%. Barium concentration in Ba-MCpSCs lagged below the normal maximum daily allowance and was stable for 4 months in mice with no evident side effects. CONCLUSIONS Such results suggest that this protocol for the isolation and microencapsulation of pSCs is compatible with long-haul transportation and that Ba-MCpSCs could be potentially employable for xenotransplantation.
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Affiliation(s)
- Giovanni Luca
- Department of Experimental Medicine, University of Perugia, Perugia, Italy.,Division of Medical Andrology and Endocrinology of Reproduction, Saint Mary Hospital, Terni, Italy
| | - Francesca Mancuso
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Mario Calvitti
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Iva Arato
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Giulia Falabella
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Antonello Bufalari
- Department of Pathology, Diagnostic and Clinical Veterinary Medicine, University of Perugia, Perugia, Italy
| | - Valentina De Monte
- Department of Pathology, Diagnostic and Clinical Veterinary Medicine, University of Perugia, Perugia, Italy
| | - Enrico Tresoldi
- Experimental Zooprophylactic Institute of Lombardia and Emilia Romagna, Brescia, Italy
| | - Claudio Nastruzzi
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Giuseppe Basta
- Department of Medicine, University of Perugia, Perugia, Italy
| | | | - Cinzia Lilli
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Catia Bellucci
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Tiziano Baroni
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | | | - Stefano Giovagnoli
- Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy
| | - Don F Cameron
- Department of Internal Medicine, University of South Florida, Tampa, FL, USA
| | - Maria Bodo
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Riccardo Calafiore
- Division of Medical Andrology and Endocrinology of Reproduction, Saint Mary Hospital, Terni, Italy.,Department of Medicine, University of Perugia, Perugia, Italy
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Makanji Y, Zhu J, Mishra R, Holmquist C, Wong WPS, Schwartz NB, Mayo KE, Woodruff TK. Inhibin at 90: from discovery to clinical application, a historical review. Endocr Rev 2014; 35:747-94. [PMID: 25051334 PMCID: PMC4167436 DOI: 10.1210/er.2014-1003] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
When it was initially discovered in 1923, inhibin was characterized as a hypophysiotropic hormone that acts on pituitary cells to regulate pituitary hormone secretion. Ninety years later, what we know about inhibin stretches far beyond its well-established capacity to inhibit activin signaling and suppress pituitary FSH production. Inhibin is one of the major reproductive hormones involved in the regulation of folliculogenesis and steroidogenesis. Although the physiological role of inhibin as an activin antagonist in other organ systems is not as well defined as it is in the pituitary-gonadal axis, inhibin also modulates biological processes in other organs through paracrine, autocrine, and/or endocrine mechanisms. Inhibin and components of its signaling pathway are expressed in many organs. Diagnostically, inhibin is used for prenatal screening of Down syndrome as part of the quadruple test and as a biochemical marker in the assessment of ovarian reserve. In this review, we provide a comprehensive summary of our current understanding of the biological role of inhibin, its relationship with activin, its signaling mechanisms, and its potential value as a diagnostic marker for reproductive function and pregnancy-associated conditions.
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Affiliation(s)
- Yogeshwar Makanji
- Department of Obstetrics and Gynecology (Y.M., J.Z., C.H., W.P.S.W., T.K.W.), Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60610; Center for Molecular Innovation and Drug Discovery (R.M., C.H.), Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208; and Department of Molecular Biosciences (N.B.S., K.E.M., T.K.W.), Center for Reproductive Science, Northwestern University, Evanston, Illinois 60208
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Abarikwu SO, Pant AB, Farombi EO. Effects of quercetin on mRNA expression of steroidogenesis genes in primary cultures of Leydig cells treated with atrazine. Toxicol In Vitro 2013. [DOI: 10.1016/j.tiv.2012.11.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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Hedger MP, Winnall WR. Regulation of activin and inhibin in the adult testis and the evidence for functional roles in spermatogenesis and immunoregulation. Mol Cell Endocrinol 2012; 359:30-42. [PMID: 21964464 DOI: 10.1016/j.mce.2011.09.031] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 09/16/2011] [Accepted: 09/16/2011] [Indexed: 02/03/2023]
Abstract
Activin A provides a unique link between reproduction and immunity, which is especially significant in the adult testis. This cytokine, together with inhibin B and follistatin acting as regulators of activin A activity, is fundamentally involved in the regulation of spermatogenesis and testicular steroidogenesis. However, activin A also has a much broader role in control of inflammation, fibrosis and immunity. In the Sertoli cell, activin A is regulated by signalling pathways that normally regulate stress and inflammation, signalling pathways that intersect with the classical hormonal regulatory pathways mediated by FSH. Modulation of activin A production and activity during spermatogenesis is implicated in the fine control of the cycle of the seminiferous epithelium. The immunoregulatory properties of activin A also suggest that it may be involved in maintaining testicular immune privilege. Consequently, elevated activin A production within the testis during inflammation and infection may contribute to spermatogenic failure, fibrosis and testicular damage.
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Affiliation(s)
- Mark P Hedger
- Monash Institute of Medical Research, Monash University, Melbourne, Victoria, Australia.
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Grieco V, Banco B, Ferrari A, Rota A, Faustini M, Veronesi MC. Inhibin-α Immunohistochemical Expression in Mature and Immature Canine Sertoli and Leydig Cells. Reprod Domest Anim 2011; 46:920-3. [DOI: 10.1111/j.1439-0531.2011.01784.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Burns BM, Gazzola C, Holroyd RG, Crisp J, McGowan MR. Male Reproductive Traits and Their Relationship to Reproductive Traits in Their Female Progeny: A Systematic Review. Reprod Domest Anim 2011; 46:534-53. [DOI: 10.1111/j.1439-0531.2011.01748.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Noguchi M, Yoshioka K, Itoh S, Suzuki C, Arai S, Wada Y, Hasegawa Y, Kaneko H. Peripheral concentrations of inhibin A, ovarian steroids, and gonadotropins associated with follicular development throughout the estrous cycle of the sow. Reproduction 2010; 139:153-61. [DOI: 10.1530/rep-09-0018] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We investigated changes in peripheral concentrations of inhibin A, total inhibin, steroids, and gonadotropins throughout the intact estrous cycle of the sow in relation to ovarian changes determined by daily transrectal ultrasonography. All visible follicles of 3 mm or more in diameter were classified as small (≥3 and <6 mm) or large (≥6 mm). Follicular recruitment was identified in two periods of the cycle: one from the late luteal to the follicular phase, characterized by an increase in the number of small follicles followed by the appearance of large follicles; and another during the early luteal phase, consisting only of increased numbers of small follicles. Plasma concentrations of inhibin A increased (P<0.05), coinciding with the two periods of follicle emergence. Estradiol (E2) levels increased (P<0.05) during the follicular phase, but not during the early luteal phase. An inverse relationship (P<0.01) between the patterns of inhibin and FSH concentrations was noted around the two periods of follicle emergence, but there was no relationship (P≥0.1) between the patterns of plasma E2and FSH during the early luteal phase. In conclusion, measurement of plasma inhibin A levels combined with ultrasonographic examination of the ovaries revealed two periods of synchronous follicular growth during the sow's estrous cycle. The results strongly suggest that inhibin A functions as a negative feedback regulator of FSH secretion throughout the estrous cycle, whereas E2appears to influence FSH secretion only during the follicular phase.
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Kaneko H, Kikuchi K, Nakai M, Noguchi J. Endocrine status and development of porcine testicular tissues in host mice. J Reprod Dev 2008; 54:480-5. [PMID: 18854642 DOI: 10.1262/jrd.20081] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Clarification of the endocrine status of host mice provides us with basic knowledge with which we can manipulate the growth and function of xenografted testicular tissues. We investigated the hormonal profiles of castrated mice grafted with porcine immature testicular tissues from 30 to 210 or more days after grafting (day 0=castration and grafting). The serum follicle stimulating hormone (FSH) concentrations of the host mice declined (P<0.05) from day 60 compared with those of the castrated, ungrafted mice. The serum inhibin and testosterone levels were higher (P<0.05) than those in the castrated, ungrafted mice from days 30 and 90 days, respectively. The inhibin levels further increased (P<0.05) from day 90, during which time the levels were higher (P<0.05) than those in the intact male mice. In the grafts, formation of lumens occurred in the seminiferous cords on day 90 and spermatozoa appeared in the lumens from day 120. However, spermatogenesis in the grafts did not reach the qualitatively normal levels observed in adult boars. The intensity of the immune reaction to inhibin alpha subunits in the Sertoli cells of the grafts decreased with differentiation of the seminiferous tubules. The present findings indicate that a feedback loop was established between the mouse hypothalamo-pituitary axis and the grafted porcine tissues from 60 days post-grafting. The results also indicate that the serum inhibin levels in the host mice remained high even after the appearance of lumens in the seminiferous tubules of the grafted tissues; this is strikingly different to the situation in normal male animals, in which the serum inhibin levels decline at around the time of tubular differentiation. The lack of efferent ducts in the tubules of the grafted tissues probably caused the accumulation of inhibin to be released into the lumens, resulting in high concentrations of circulating inhibin. These high levels of inhibin may directly affect spermatogenic activity and suppress FSH secretion.
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Affiliation(s)
- Hiroyuki Kaneko
- Reproductive Biology Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Japan.
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Ohnuma K, Kaneko H, Noguchi J, Kikuchi K, Ozawa M, Hasegawa Y. Production of inhibin A and inhibin B in boars: changes in testicular and circulating levels of dimeric inhibins and characterization of inhibin forms during testis growth. Domest Anim Endocrinol 2007; 33:410-21. [PMID: 17010559 DOI: 10.1016/j.domaniend.2006.08.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2006] [Revised: 08/08/2006] [Accepted: 08/17/2006] [Indexed: 10/24/2022]
Abstract
We investigated the production of inhibin in boars from the infantile to pubertal periods by: (1) measurement of testicular and circulating levels of inhibin, (2) characterization of inhibin forms and (3) localization of inhibin alpha subunits in the testis. Total inhibin levels in the testis increased until 8 weeks of age but then declined to much lower values at 15 weeks. Testicular inhibin A and inhibin B were high until 8 weeks. Circulating levels of total inhibin and inhibin A were also high until 8 weeks, then declined from 10 weeks; inhibin B was not detected, because of low sensitivity of the inhibin B assay. Analyses of inhibin A and inhibin B levels in the eluted fractions obtained from testes after immunoaffinity chromatography and SDS-PAGE showed the presence of a peak of approximately 45 kDa until 10 weeks of age. As the boars aged, the levels of inhibin A and inhibin B increased in the molecular weight region of 29-31 kDa. The fractions corresponding to 29 and 30 kDa suppressed FSH release from rat pituitary cells, but the 45 kDa fraction had no FSH-suppressing activity. Total amounts of inhibin A isolated from the SDS gels were similar to those of inhibin B until 10 weeks of age, but were three times higher than those of inhibin B between 15 and 25 weeks. Further fractionation by reverse phase high-performance liquid chromatography revealed that the 29-31 kDa immunoreactive material was composed of mature forms of inhibin A and inhibin B, in addition to a 26 kDa alpha monomer. Immunohistochemistry indicated that positive immunostaining for the alpha subunits was observed in Sertoli cells from the infantile to pubertal periods. Elongated spermatids also showed positive signals at age 25 weeks. These results clearly indicated that: (1) the boar testis has the ability to produce inhibin A and inhibin B during the infantile period but inhibin A is the predominant form towards puberty and (2) the molecular weight forms of inhibin and the sites of production of inhibin change with testicular development.
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Affiliation(s)
- Katsuhiko Ohnuma
- Reproductive Biology Research Unit (Kannondai), National Institute of Agrobiological Science, Tsukuba, Ibaraki 305-8602, Japan
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KANEKO H, HASEGAWA Y. Application of time-resolved fluorometry to immunoassays for bovine reproductive hormones. Anim Sci J 2007. [DOI: 10.1111/j.1740-0929.2006.00398.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kaneko H, Matsuzaki M, Noguchi J, Kikuchi K, Ohnuma K, Ozawa M. Changes in Circulating and Testicular Levels of Inhibin A and B During Postnatal Development in Bulls. J Reprod Dev 2006; 52:741-9. [PMID: 16946582 DOI: 10.1262/jrd.18060] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We investigated testicular and circulating levels of dimeric inhibins in Holstein bulls from the infantile to postpubertal periods (5 to 50 weeks of age) and examined the relationship between the profiles of circulating dimeric inhibins and FSH. Concentrations of total inhibin and inhibin B in the testis were highest at 4 to 5 weeks of age but decreased gradually as the bulls aged. Testicular inhibin A levels showed a gradual decline to a nadir at 15 to 26 weeks of age, but by 39 weeks, they were high again. The contents of total inhibin, inhibin A, and inhibin B per testis generally increased with age. Fractionation of testicular homogenates obtained from 15-week-old bulls by a combination of immunoaffinity chromatography and SDS-PAGE confirmed the presence of two major molecular weight forms (32 and 45 kDa) of dimeric inhibins in the testes. Circulating levels of total inhibin and inhibin A showed a significant increase in bulls at around 10 to 14 weeks of age compared to the levels between 5 and 7 weeks of age but decreased thereafter. However, immunoreactivity for inhibin B was not detected in the peripheral circulation, probably because of low sensitivity of the inhibin B assays. The concentrations of plasma FSH were high at 5 weeks of age but declined to lower levels between 11 and 40 weeks, and then increased from 41 weeks onward. There was no significant correlation between the plasma levels of FSH and inhibin A or total inhibin. The results clearly indicate that the bull testis produces inhibin A and B and secretes at least inhibin A into the circulation during postnatal development. However, the profile of circulating FSH in bulls shows no reciprocal relationship with the inhibin A or total inhibin profile during the postnatal period.
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Affiliation(s)
- Hiroyuki Kaneko
- Reproductive Biology Research Unit (Kannondai), Division of Animal Sciences, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan.
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Phillips DJ. Activins, inhibins and follistatins in the large domestic species. Domest Anim Endocrinol 2005; 28:1-16. [PMID: 15620803 DOI: 10.1016/j.domaniend.2004.05.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2004] [Accepted: 05/31/2004] [Indexed: 11/26/2022]
Abstract
The activins and inhibins are members of the transforming growth factor-beta (TGF-beta) superfamily and, along with follistatin, a high affinity binding protein of activin, form a group of interrelated factors originally isolated for their role in regulating the release of follicle-stimulating hormone (FSH). Knowledge of their function, particularly that of activin, has expanded since being originally isolated, such that they are now regarded as important paracrine regulators in many cellular systems. This review summarizes the biology of these proteins as has been established in the large domestic animals. While the majority of data relate to the pituitary, ovary, uterus/placenta and testis, consideration is also given to emerging roles in inflammatory processes and in non-reproductive tissues or systems.
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Affiliation(s)
- David J Phillips
- Center for Molecular Reproduction & Endocrinology, Monash Institute of Reproduction & Development, Monash University, Clayton, Vic. 3168, Australia.
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Abstract
Various barriers in the testis may prevent hormones from readily reaching the cells they are supposed to stimulate, especially the hydrophilic hormones from the pituitary. For example, LH must pass through or between the endothelial cells lining the blood vessels to reach the surface of the Leydig cells, and FSH has the additional barrier of the peritubular myoid cells before it reaches the Sertoli cells. The specialised junctions between pairs of Sertoli cells would severely restrict the passage of peptides from blood to the luminal fluid and therefore to the cells inside this barrier, such as the later spermatocytes and spermatids. There is evidence in the literature that radioactively labelled LH does not pass readily into the testis from the blood, and the concentration of native LH in the interstitial extracellular fluid surrounding the Leydig cells in rats is only about one-fifth of that in blood plasma. Furthermore, after injection with LHRH, there are large rises in LH in the blood within 15 min, at which time the Leydig cells have already responded by increasing their content of testosterone, but with no significant change in the concentration of LH in the interstitial extracellular fluid. Either the Leydig cells respond to very small changes in LH, or the testicular endothelial cells in some way mediate the response of the Leydig cells to LH, for which there is now some evidence from co-cultures of endothelial and Leydig cells. The lipophilic steroid hormones, such as testosterone, which are produced by the Leydig cells, have actions within the seminiferous tubules in the testis but also in other parts of the body. They should pass more readily through cells than the hydrophilic peptides; however, the concentration of testosterone in the fluid inside the seminiferous tubules is less than in the interstitial extracellular fluid in the testis, especially after stimulation by LH released after injection of LHRH and despite the presence inside the tubules of high concentrations of an androgen-binding protein. The concentration of testosterone in testicular venous blood does not rise to the same extent as that in the interstitial extracellular fluid, suggesting that there may also be some restriction to movement of the steroid across the endothelium. There is a very poor correlation between the concentrations of testosterone in fluids from the various compartments of the testis and in peripheral blood plasma. Determination of the testosterone concentration in the whole testis is also probably of little predictive value, because the high concentrations of lipid in the Leydig cells would tend to concentrate testosterone there, and hormones inside these cells are unlikely to have any direct effect on other cells in the testis. The best predictor of testosterone concentrations around cells in the testis is the level of testosterone in testicular venous blood, the collection of which for testosterone analysis is a reasonably simple procedure in experimental animals and should be substituted for tissue sampling. There seems to be no simple way of determining the concentrations of peptide hormones in the vicinity of the testicular cells.
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