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Bharath Kumar BS, Mallick S, Manjunathachar HV, Shashank CG, Sharma A, Nagoorvali D, Soren S, Jadhav VG, Pandita S. In vitro effects of uncarboxylated osteocalcin on buffalo Leydig cell steroidogenesis. Vet Res Commun 2024; 48:1423-1433. [PMID: 38305958 DOI: 10.1007/s11259-024-10320-4] [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: 11/21/2023] [Accepted: 01/29/2024] [Indexed: 02/03/2024]
Abstract
Uncarboxylated osteocalcin (UcOCN), a bone derived circulating protein, has been demonstrated to influence steroidogenesis in testicular Leydig cells of murine and human species. However, the role of UcOCN in testosterone biosynthesis remains unexplored in domestic animals. The present study aimed to investigate the impact of UcOCN on the expressions of steroidogenic genes (HSD3β1, HSD3β6, CYP17A1, CYP11A1), testosterone production and GPRC6A receptor localization in buffalo Leydig cells. Leydig cells from the testes of adult Murrah buffalo were isolated, with an average cell count and viability after digestion and Percoll enrichment of 1.43 × 106 cells/g of testes and 78.5%, respectively. Immunophenotyping of Percoll-enriched cell suspension by flow cytometry showed populations of Leydig cells ranging between 69 and 73.9%. Immunostaining confirmed the presence of GPRC6A receptors and CYP11A1 positive Leydig cells. When these cells were cultured and incubated with varying levels of UcOCN (6, 12, 24, and 48 ng/ml) and LH, there was a significant (P < 0.01) increase in testosterone production and up-regulation (P < 0.05) of CYP11A1, CYP17A1, HSD3β1 and HSD3β6 gene expression. In summary, the present study underscored the effects of UcOCN on testosterone biosynthesis, expression of crucial steroidogenic genes and interaction with GPRC6A receptors in buffalo Leydig cells, emphasizing its potential implications in andrology.
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Affiliation(s)
- B S Bharath Kumar
- ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.
- Department of Animal Husbandry, Government of Karnataka, Bengaluru, Karnataka, India.
| | - Smrutirekha Mallick
- ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India.
- ICAR-National Institute on Foot and Mouth Disease, Bhubaneswar, Odisha, 752050, India.
| | - H V Manjunathachar
- ICAR-Indian Veterinary Research Institute, Bareilly, U.P., 243122, India
- ICMR-National Institute of Traditional Medicine, Belagavi, Karnataka, 590010, India
| | - C G Shashank
- ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India
| | - Ankur Sharma
- ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India
| | | | - Simson Soren
- ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India
| | | | - Sujata Pandita
- ICAR-National Dairy Research Institute, Karnal, Haryana, 132001, India
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Rehman A, Ahmad E, Sattar A, Riaz A, Khan JA, Naseer Z, Akhtar MF, Abbas M, Shi Z. Long term effects of immunization against inhibin on fresh and post-thawed semen quality and sperm kinematics during low and peak breeding seasons in Beetal bucks. Small Rumin Res 2021. [DOI: 10.1016/j.smallrumres.2021.106442] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Apoptosis of germ cells in the normal testis of the Japanese quail (Coturnix coturnix japonica). Tissue Cell 2020; 67:101450. [PMID: 33091765 DOI: 10.1016/j.tice.2020.101450] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/16/2020] [Accepted: 09/22/2020] [Indexed: 02/06/2023]
Abstract
It has been established that excess germ cells in normal and in pathological conditions are removed from testicular tissue by the mechanism of apoptosis. Studies on germ cell apoptosis in avian species are grossly lacking, and there are only a few reports on induced germ cell degenerations in the testis tissue of birds. This study was designed to investigate the process of apoptosis of germ cells in the Japanese quail (Coturnix coturnix japonica). Germ cell degenerations were investigated in birds of all age groups, namely pre-pubertal, pubertal, adult, and aged. Apoptosis of germ cells in the quails, as shown by hematoxylin & eosin (H&E), TdT dUTP Nick End Labeling (TUNEL) assay and electron microscopy, was similar to that observed in previous studies of germ cells and somatic cells of mammalian species. The observed morphological features of these apoptotic cells ranged from irregular plasma and nuclear membranes in the early stage of apoptosis to rupture of the nuclear membrane, condensation of nuclear material, as well as fragments of apoptotic bodies, in later stages of apoptosis. In the TUNEL-positive cell counts, there was a significant difference between the mean cell counts for the four age groups (P < 0.05). Post hoc analysis revealed a highly significant difference in the aged group relative to the pubertal and adult age groups, while the cell counts of the pre-pubertal group were significantly higher than those of the pubertal group. However, there was no significant difference between cell counts of the pre-pubertal and the adult, and between the pre-pubertal and the aged groups.
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Oluwole OF, Salami SA, Ogunwole E, Raji Y. Implication of caffeine consumption and recovery on the reproductive functions of adult male Wistar rats. J Basic Clin Physiol Pharmacol 2016; 27:483-491. [PMID: 27159917 DOI: 10.1515/jbcpp-2015-0134] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Accepted: 03/29/2016] [Indexed: 06/05/2023]
Abstract
BACKGROUND This study assessed the impact of caffeine consumption and recovery on reproductive functions and fertility of Wistar rats. METHODS Thirty-five adult male Wistar rats were divided into seven groups of five rats each. Group A (control) received distilled water (vehicle), while groups B, C, and D were treated orally with 10 mg/kg body weight (BW), 20 mg/kg BW, and 40 mg/kg BW caffeine, respectively, for 30 days. Groups E, F, and G were treated orally with 10 mg/kg BW, 20 mg/kg BW, and 40 mg/kg BW caffeine, respectively, for 30 days and then allowed to recover for another 30 days. RESULTS Caffeine caused a decrease in body weight, while recovery groups showed appreciable increase in body weight during recovery. Relative weight of seminal vesicle, prostate, and epididymis decreased dose dependently during treatment but increased during recovery. The liver and kidney weight increased during treatment but reduced during recovery. Sperm count was significantly decreased in both treated and recovery groups. Initial decrease in sperm viability and volume was appreciably reversed during recovery period. Serum level of testosterone increased at high doses, while serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) showed significant decrease. Histological sections of testis in treated groups showed mild congestion of the interstitial blood vessel and subcapsular congestion. However, there was no subcapsular congestion in the recovery groups. All rats in both treated and recovery groups had 100% fertilization success from fertility study. CONCLUSIONS Suggestively, caffeine treatment for 4 weeks could impair body, reproductive organs weight, sperm characteristics, LH/FSH level, and also testicular cyto-architecture. Effects appeared, however, reversible after caffeine withdrawal.
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Jiménez R, Burgos M, Barrionuevo FJ. Circannual Testis Changes in Seasonally Breeding Mammals. Sex Dev 2015; 9:205-15. [PMID: 26375035 DOI: 10.1159/000439039] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2015] [Indexed: 11/19/2022] Open
Abstract
In the non-equatorial zones of the Earth, species concentrate their reproductive effort in the more favorable season. A consequence of seasonal breeding is seasonal testis regression, which implies the depletion of the germinative epithelium, permeation of the blood-testis barrier, and reduced androgenic function. This process has been studied in a number of vertebrates, but the mechanisms controlling it are not yet well understood. Apoptosis was assumed for years to be an important effector of seasonal germ cell depletion in all vertebrates, including mammals, but an alternative mechanism has recently been reported in the Iberian mole as well as in the large hairy armadillo. It is based on the desquamation of meiotic and post-meiotic germ cells as a consequence of altered Sertoli-germ cell adhesion molecule expression and distribution. Desquamated cells are either discarded alive through the epididymis, as in the mole, or subsequently die by apoptosis, as in the armadillo. Also, recent findings on the reproductive cycle of the greater white-toothed shrew at the meridional limits of its distribution area have revealed that the mechanisms controlling seasonal breeding are in fact far more plastic and versatile than initially suspected. Perhaps these higher adaptive capacities place mammals in a better position to face the ongoing climate change.
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Affiliation(s)
- Rafael Jiménez
- Departamento de Genx00E9;tica e Instituto de Biotecnologx00ED;a, Universidad de Granada, Granada, Spain
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Jung JW, Ahn C, Shim SY, Gray PC, Kwiatkowski W, Choe S. Regulation of FSHβ induction in LβT2 cells by BMP2 and an Activin A/BMP2 chimera, AB215. J Endocrinol 2014; 223:35-45. [PMID: 25100748 DOI: 10.1530/joe-14-0317] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Activins and bone morphogenetic proteins (BMPs) share activin type 2 signaling receptors but utilize different type 1 receptors and Smads. We designed AB215, a potent BMP2-like Activin A/BMP2 chimera incorporating the high-affinity type 2 receptor-binding epitope of Activin A. In this study, we compare the signaling properties of AB215 and BMP2 in HEK293T cells and gonadotroph LβT2 cells in which Activin A and BMP2 synergistically induce FSHβ. In HEK293T cells, AB215 is more potent than BMP2 and competitively blocks Activin A signaling, while BMP2 has a partial blocking activity. Activin A signaling is insensitive to BMP pathway antagonism in HEK293T cells but is strongly inhibited by constitutively active (CA) BMP type 1 receptors. By contrast, the potencies of AB215 and BMP2 are indistinguishable in LβT2 cells and although AB215 blocks Activin A signaling, BMP2 has no inhibitory effect. Unlike HEK293T, Activin A signaling is strongly inhibited by BMP pathway antagonism in LβT2 cells but is largely unaffected by CA BMP type 1 receptors. BMP2 increases phospho-Smad3 levels in LβT2 cells, in both the absence and the presence of Activin A treatment, and augments Activin A-induced FSHβ. AB215 has the opposite effect and sharply decreases basal phospho-Smad3 levels and blocks Smad2 phosphorylation and FSHβ induction resulting from Activin A treatment. These findings together demonstrate that while AB215 activates the BMP pathway, it has opposing effects to those of BMP2 on FSHβ induction in LβT2 cells apparently due to its ability to block Activin A signaling.
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Affiliation(s)
- Jae Woo Jung
- Joint Center for BiosciencesSongdo Global University Campus, 187 Songdo-dong, Yeonsu-gu, Incheon 406-840, KoreaStructural Biology LaboratoryClayton Foundation Laboratories for Peptide BiologyThe Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Chihoon Ahn
- Joint Center for BiosciencesSongdo Global University Campus, 187 Songdo-dong, Yeonsu-gu, Incheon 406-840, KoreaStructural Biology LaboratoryClayton Foundation Laboratories for Peptide BiologyThe Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Sun Young Shim
- Joint Center for BiosciencesSongdo Global University Campus, 187 Songdo-dong, Yeonsu-gu, Incheon 406-840, KoreaStructural Biology LaboratoryClayton Foundation Laboratories for Peptide BiologyThe Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Peter C Gray
- Joint Center for BiosciencesSongdo Global University Campus, 187 Songdo-dong, Yeonsu-gu, Incheon 406-840, KoreaStructural Biology LaboratoryClayton Foundation Laboratories for Peptide BiologyThe Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Witek Kwiatkowski
- Joint Center for BiosciencesSongdo Global University Campus, 187 Songdo-dong, Yeonsu-gu, Incheon 406-840, KoreaStructural Biology LaboratoryClayton Foundation Laboratories for Peptide BiologyThe Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA Joint Center for BiosciencesSongdo Global University Campus, 187 Songdo-dong, Yeonsu-gu, Incheon 406-840, KoreaStructural Biology LaboratoryClayton Foundation Laboratories for Peptide BiologyThe Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Senyon Choe
- Joint Center for BiosciencesSongdo Global University Campus, 187 Songdo-dong, Yeonsu-gu, Incheon 406-840, KoreaStructural Biology LaboratoryClayton Foundation Laboratories for Peptide BiologyThe Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA Joint Center for BiosciencesSongdo Global University Campus, 187 Songdo-dong, Yeonsu-gu, Incheon 406-840, KoreaStructural Biology LaboratoryClayton Foundation Laboratories for Peptide BiologyThe Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA
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Kheradmand A, Dezfoulian O, Alirezaei M. Ghrelin regulates Bax and PCNA but not Bcl-2 expressions following scrotal hyperthermia in the rat. Tissue Cell 2012; 44:308-15. [PMID: 22658447 DOI: 10.1016/j.tice.2012.04.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2012] [Revised: 04/23/2012] [Accepted: 04/29/2012] [Indexed: 12/17/2022]
Abstract
More recently, we have reported the beneficial effects of ghrelin in improvement of histopathological features of the rat testis following local heat exposure. However, the exact mechanism and the precise role of apoptosis- and proliferation-specific proteins in this regeneration process remained to be explored. Thus, thirty adult male Wistar rats were allotted for the experiment and subdivided equally into three groups: control-saline (CS), heat-saline (HS) and heat-ghrelin (HG). The scrota of HS and HG groups were immersed once in water bath at 43°C for 15 min. HG animals received 2 nmol of ghrelin subcutaneously immediately after heating every other day until day 60 and the other groups were given physiological saline using the same method. The testes of all groups were taken after rat killing on days 30 and 60 after heat treatment for immunocytochemical detection of pro-apoptotic factor Bax, anti-apoptotic protein Bcl-2 and proliferation-associated peptide PCNA in the germ cells. Ghrelin could significantly suppress the Bax expression in spermatocytes compared to the HS group at day 30 (P<0.05). Likewise, the mean percentages of spermatogonia containing Bax substance were lower in ghrelin-exposed animals, however the differences were not statistically significant. There were immunoreactive cells against Bcl-2 in each germ cell neither in the control nor in the heated animals of experimental groups. In contrast, the number of PCNA immunolabeling cells were higher in HG group in compared to HS or CS animals on both experimental days (P<0.001). Down-regulation of Bax expression concurrent with overexpression of PCNA in HG group indicates the ability of ghrelin in acceleration of testicular germ cells regeneration following heat stress. These findings indicate that ghrelin may be used as a novel and efficient antioxidant agent to induce resumption of spermatogenesis upon environmental heat exposure.
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Affiliation(s)
- Arash Kheradmand
- Department of Clinical Sciences, School of Veterinary Medicine, Lorestan University, P.O. Box: 465, Khorram Abad, Iran.
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Cai K, Hua G, Ahmad S, Liang A, Han L, Wu C, Yang F, Yang L. Action mechanism of inhibin α-subunit on the development of Sertoli cells and first wave of spermatogenesis in mice. PLoS One 2011; 6:e25585. [PMID: 21998670 PMCID: PMC3187785 DOI: 10.1371/journal.pone.0025585] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 09/06/2011] [Indexed: 01/09/2023] Open
Abstract
Inhibin is an important marker of Sertoli cell (SC) activity in animals with impaired spermatogenesis. However, the precise relationship between inhibin and SC activity is unknown. To investigate this relationship, we partially silenced both the transcription and translation of the gene for the α-subunit of inhibin, Inha, using recombinant pshRNA vectors developed with RNAi-Ready pSIREN-RetroQ-ZsGreen Vector (Clontech Laboratories, Mountain View, Calif). We found that Inha silencing suppresses the cell-cycle regulators Cyclin D1 and Cyclin E and up-regulates the cell-cycle inhibitor P21 (as detected by Western blot analysis), thereby increasing the number of SCs in the G1 phase of the cell cycle and decreasing the amount in the S-phase of the cell cycle (as detected by flow cytometry). Inha silencing also suppressed Pdgfa, Igf1, and Kitl mRNA levels and up-regulated Tgfbrs, Inhba, Inhbb, Cyp11a1, Dhh, and Tjp1 mRNA levels (as indicated by real-time polymerase chain reaction [PCR] analysis). These findings indicate that Inha has the potential to influence the availability of the ligand inhibin and its antagonist activin in the SC in an autocrine manner and inhibit the progression of SC from G1 to S. It may also participate in the development of the blood–testis barrier, Leydig cells, and spermatogenesis through its effect on Dhh, Tjp1, Kitl, and Pdgfa. Real-time PCR and Western blot analyses of Inha, Inhba, and Inhbb mRNA and Inha levels over time show that Inha plays an important role in the formation of round spermatid during the first wave of spermatogenesis in mice.
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Affiliation(s)
- Kailai Cai
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Guohua Hua
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Sibtain Ahmad
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, Huazhong Agricultural University, Wuhan, People's Republic of China
- Department of Livestock Management, University of Agriculture, Faisalabad, Pakistan
| | - Aaixin Liang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Li Han
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Canjie Wu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Feifei Yang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, Huazhong Agricultural University, Wuhan, People's Republic of China
| | - Liguo Yang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Education Ministry of China, Huazhong Agricultural University, Wuhan, People's Republic of China
- * E-mail:
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List EO, Sackmann-Sala L, Berryman DE, Funk K, Kelder B, Gosney ES, Okada S, Ding J, Cruz-Topete D, Kopchick JJ. Endocrine parameters and phenotypes of the growth hormone receptor gene disrupted (GHR-/-) mouse. Endocr Rev 2011; 32:356-86. [PMID: 21123740 PMCID: PMC3365798 DOI: 10.1210/er.2010-0009] [Citation(s) in RCA: 137] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Disruption of the GH receptor (GHR) gene eliminates GH-induced intracellular signaling and, thus, its biological actions. Therefore, the GHR gene disrupted mouse (GHR-/-) has been and is a valuable tool for helping to define various parameters of GH physiology. Since its creation in 1995, this mouse strain has been used by our laboratory and others for numerous studies ranging from growth to aging. Some of the most notable discoveries are their extreme insulin sensitivity in the presence of obesity. Also, the animals have an extended lifespan, which has generated a large number of investigations into the roles of GH and IGF-I in the aging process. This review summarizes the many results derived from the GHR-/- mice. We have attempted to present the findings in the context of current knowledge regarding GH action and, where applicable, to discuss how these mice compare to GH insensitivity syndrome in humans.
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Affiliation(s)
- Edward O List
- The Edison Biotechnology Institute, Ohio University, Athens, Ohio 45701, USA
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Kheradmand A, Dezfoulian O, Tarrahi MJ. Ghrelin attenuates heat-induced degenerative effects in the rat testis. ACTA ACUST UNITED AC 2010; 167:97-104. [PMID: 21167869 DOI: 10.1016/j.regpep.2010.12.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Revised: 12/04/2010] [Accepted: 12/07/2010] [Indexed: 10/18/2022]
Abstract
This study was conducted to examine the efficacy of ghrelin in prevention of deleterious effects of heat stress in rat testicular tissue. Forty five adult male rats were scheduled for this study and were divided equally into three groups: heat-saline, heat-ghrelin and control-saline. The scrota of heated-designed rats were immersed once in water bath at 43 °C for 15 min. Immediately upon heating, 2 nmol of ghrelin were given subcutaneously to heat-ghrelin animals every other day up to day 60 and physiological saline to the other two groups using the same method. The animals were sacrificed at 10, 30 and 60 days after heat treatment and their testes were taken for later photomicrograph and immunohistochemical analysis. Testicular histopathology revealed a significant reduction in the means of seminiferous tubules and Sertoli cell nucleus diameters as well as germinal epithelium height on day 10 in both heated groups. Furthermore, other testicular components including miotic index, spermatogenesis rate, presence of spermatocytes and volume densities were dramatically decreased following heat exposure. Notably, ghrelin caused a partial recovery in all of the above-mentioned parameters and accelerated testicular regeneration process by day 30 compared to the heat-saline group (P<0.05). Because of testicular progressive recovery, these indices were similar among groups on day 60 (P>0.05). However, immunohistochemistry evaluation for in situ detection of Bcl-2 protein did not exhibit any germ cells-positive of this factor among groups at different experimental days. In conclusion, the results of the present study indicate for the first time the novel evidences of ghrelin ability in attenuation of heat-induced testicular damage and also that ghrelin therapy may be useful as a suppressor of degenerative effects following testicular hyperthermia.
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Affiliation(s)
- Arash Kheradmand
- Department of Clinical Sciences, School of Veterinary Medicine, Lorestan University, P. O. Box: 465, Khorram Abad, Iran.
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Chauhan N, Saraf D, Dixit V. Effect of vajikaran rasayana herbs on pituitary–gonadal axis. Eur J Integr Med 2010. [DOI: 10.1016/j.eujim.2010.03.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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12
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Dadhich RK, Real FM, Zurita F, Barrionuevo FJ, Burgos M, Jiménez R. Role of apoptosis and cell proliferation in the testicular dynamics of seasonal breeding mammals: a study in the Iberian mole, Talpa occidentalis. Biol Reprod 2010; 83:83-91. [PMID: 20357272 DOI: 10.1095/biolreprod.109.080135] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Apoptosis and cell proliferation are two important cellular processes known to be involved in the normal functioning of the testis in nonseasonally breeding mammals, but there is some controversy concerning their roles in the gonads of males from seasonally breeding species. We have studied the processes of apoptosis and cell proliferation in the testes of males of the Iberian mole (Talpa occidentalis), a species showing a strict seasonal reproduction pattern. Both males and females are sexually active during the winter and completely inactive in the summer, with two transitional periods, in the autumn and the spring. Adult males from these four reproductive stages were captured, and their testes were immunohistochemically studied for the presence of apoptotic and proliferation molecular markers as well for other testicular and meiotic cell-specific markers. We found that apoptosis varies in a season-dependent manner in the testes of male moles, affecting mainly late zygotene and pachytene cells during the period of sexual inactivity, but it does not differentially affect the number of Sertoli cells. More interestingly, apoptosis is not responsible for the massive germ-cell depletion occurring during mole testis regression. In addition, a wave of spermatogonial cell proliferation appears to restore the number of spermatogonia lost during the period of testis inactivity. According to current knowledge, data from moles indicate that mammals do not form a homogeneous group regarding the mechanisms by which the cell-content dynamics are regulated in the testes of males from seasonally breeding species.
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Affiliation(s)
- Rajesh K Dadhich
- Departamento de Genética e Instituto de Biotecnología, Universidad de Granada, Centro de Investigación Biomédica, Granada, Spain
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Divergent development of testosterone secretion in male zebu (Bos indicus) and crossbred cattle (Bos indicus x Bos taurus) and buffaloes (Bubalus bubalis) during growth. Trop Anim Health Prod 2010; 42:1143-8. [DOI: 10.1007/s11250-010-9538-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2010] [Indexed: 10/19/2022]
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Ebling FJP, Nwagwu MO, Baines H, Myers M, Kerr JB. The hypogonadal (hpg) mouse as a model to investigate the estrogenic regulation of spermatogenesis. HUM FERTIL 2009; 9:127-35. [PMID: 17008264 DOI: 10.1080/14647270500509103] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The hypogonadal (hpg) mouse is an excellent animal model in which to investigate the mechanism of action of estrogens on spermatogenesis because it has arrested reproductive development without the need for surgical, endocrine, pharmacological or immunological intervention. Hpg mice are hypogonadotrophic and fail to show normal postnatal testicular development due to the congenital inability to synthesize gonadotropin-releasing hormone in the hypothalamus. The hpg testis remains responsive to gonadotropins and androgens in that fertility can be induced by treatment with these hormones. Surprisingly, chronic treatment with low concentrations of estradiol alone induces qualitatively normal spermatogenesis. The induction of testicular development by estradiol in hpg mice is accompanied by a paradoxical increase in FSH production. The actions of estradiol in hpg mice appear to be via genomic estrogen receptors, as concurrent treatment with estrogen-receptor antagonist ICI182,780 completely blocks these pituitary and testis responses. Concurrent treatment with the androgen receptor antagonist bicalutamide does not affect the estradiol-induced increase in pituitary FSH content, but markedly attenuates the estradiol-induced increase in testicular weight. Western blot analyses and immunohistochemistry provide evidence for estrogen-receptor alpha and beta expression in both pituitary gland and testis of the hpg mouse. Estradiol may therefore exert direct actions within the testes and/or indirect neuroendocrine actions via the release of FSH or other hormones from the pituitary gland, but its actions are dependent upon the availability of low levels of androgen within the testis.
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Affiliation(s)
- Francis J P Ebling
- School of Biomedical Sciences, University of Nottingham Medical School, Queen's Medical Centre, Nottingham NG7 2UH, United Kingdom.
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Wang RS, Yeh S, Tzeng CR, Chang C. Androgen receptor roles in spermatogenesis and fertility: lessons from testicular cell-specific androgen receptor knockout mice. Endocr Rev 2009; 30:119-32. [PMID: 19176467 PMCID: PMC2662628 DOI: 10.1210/er.2008-0025] [Citation(s) in RCA: 323] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Androgens are critical steroid hormones that determine the expression of the male phenotype, including the outward development of secondary sex characteristics as well as the initiation and maintenance of spermatogenesis. Their actions are mediated by the androgen receptor (AR), a member of the nuclear receptor superfamily. AR functions as a ligand-dependent transcription factor, regulating expression of an array of androgen-responsive genes. Androgen and the AR play important roles in male spermatogenesis and fertility. The recent generation and characterization of male total and conditional AR knockout mice from different laboratories demonstrated the necessity of AR signaling for both external and internal male phenotype development. As expected, the male total AR knockout mice exhibited female-typical external appearance (including a vagina with a blind end and a clitoris-like phallus), the testis was located abdominally, and germ cell development was severely disrupted, which was similar to a human complete androgen insensitivity syndrome or testicular feminization mouse. However, the process of spermatogenesis is highly dependent on autocrine and paracrine communication among testicular cell types, and the disruption of AR throughout an experimental animal cannot answer the question about how AR in each type of testicular cell can play roles in the process of spermatogenesis. In this review, we provide new insights by comparing the results of cell-specific AR knockout in germ cells, peritubular myoid cells, Leydig cells, and Sertoli cells mouse models that were generated by different laboratories to see the consequent defects in spermatogenesis due to AR loss in different testicular cell types in spermatogenesis. Briefly, this review summarizes these results as follows: 1) the impact of lacking AR in Sertoli cells mainly affects Sertoli cell functions to support and nurture germ cells, leading to spermatogenesis arrest at the diplotene primary spermatocyte stage prior to the accomplishment of first meiotic division; 2) the impact of lacking AR in Leydig cells mainly affects steroidogenic functions leading to arrest of spermatogenesis at the round spermatid stage; 3) the impact of lacking AR in the smooth muscle cells and peritubular myoid cells in mice results in similar fertility despite decreased sperm output as compared to wild-type controls; and 4) the deletion of AR gene in mouse germ cells does not affect spermatogenesis and male fertility. This review tries to clarify the useful information regarding how androgen/AR functions in individual cells of the testis. The future studies of detailed molecular mechanisms in these in vivo animals with cell-specific AR knockout could possibly lead to useful insights for improvements in the treatment of male infertility, hypogonadism, and testicular dysgenesis syndrome, and in attempts to create safe as well as effective male contraceptive methods.
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Affiliation(s)
- Ruey-Sheng Wang
- Department of Pathology and Urology, George Whipple Laboratory for Cancer Research, University of Rochester Medical Center, Rochester, New York 14642, USA
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Kheradmand A, Roshangar L, Taati M. The role of ghrelin on the morphometry and intracellular changes in the rat testis. Tissue Cell 2009; 41:105-11. [DOI: 10.1016/j.tice.2008.07.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 07/22/2008] [Accepted: 07/25/2008] [Indexed: 10/21/2022]
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The Role of the Leydig Cell in Spermatogenic Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 636:255-69. [DOI: 10.1007/978-0-387-09597-4_14] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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18
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SEDQYAR M, WENG Q, WATANABE G, KANDIEL MM, TAKAHASHI S, SUZUKI AK, TANEDA S, TAYA K. Secretion of Inhibin in Male Japanese Quail ( Coturnix japonica) from One Week of Age to Sexual Maturity. J Reprod Dev 2008; 54:100-6. [DOI: 10.1262/jrd.19155] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Manila SEDQYAR
- Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology
| | - Qiang WENG
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology
- College of Biological Science and Technology, Beijing Forestry University
| | - Gen WATANABE
- Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology
| | - Mohamed M.M. KANDIEL
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology
- Department of Theriogenology, Faculty of Veterinary Medicine, Benha University
| | - Sinji TAKAHASHI
- Ecological Effect Research Team, Dioxin and Environmental Endocrine Disrupter Research Project, National Institute for Environmental Studies
| | - Akira K SUZUKI
- Environmental Nanotoxicology Section, Research Center for Environmental Risk, National Institute for Environmental Studies
| | - Shinji TANEDA
- Environmental Nanotoxicology Section, Research Center for Environmental Risk, National Institute for Environmental Studies
| | - Kazuyoshi TAYA
- Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University
- Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology
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Dufau ML, Tsai-Morris CH. Gonadotropin-regulated testicular helicase (GRTH/DDX25): an essential regulator of spermatogenesis. Trends Endocrinol Metab 2007; 18:314-20. [PMID: 17889551 DOI: 10.1016/j.tem.2007.09.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2007] [Revised: 09/10/2007] [Accepted: 09/10/2007] [Indexed: 12/27/2022]
Abstract
Male germ-cell maturation is orchestrated by a cascade of temporally regulated factors. Gonadotropin-regulated testicular helicase (GRTH/DDX25), a target of gonadotropin and androgen action, is a post-transcriptional regulator of key spermatogenesis genes. Male mice lacking GRTH are sterile, with spermatogenic arrest owing to the failure of round spermatids to elongate. GRTH is a component of messenger ribonucleoprotein particles, which transport target mRNAs to the cytoplasm for storage in chromatoid bodies of spermatids; these messages are released for translation during spermatogenesis. GRTH is also found in polyribosomes, where it regulates the translation of mRNAs encoding spermatogenesis factors. The association of GRTH mutations with male infertility underlines the importance of GRTH as a central, post-transcriptional regulator of spermatogenesis.
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Affiliation(s)
- Maria L Dufau
- Section on Molecular Endocrinology, Endocrinology and Reproduction Research Branch, National Institutes of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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20
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Eacker SM, Shima JE, Connolly CM, Sharma M, Holdcraft RW, Griswold MD, Braun RE. Transcriptional profiling of androgen receptor (AR) mutants suggests instructive and permissive roles of AR signaling in germ cell development. Mol Endocrinol 2007; 21:895-907. [PMID: 17244764 DOI: 10.1210/me.2006-0113] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The androgen receptor (AR) is a transcription factor that plays a critical role in male sexual development, spermatogenesis, and maintenance of hormonal homeostasis. Despite the extensive knowledge of the phenotypic consequences of mutations in Ar, very little is known about the transcriptional targets of AR within the testis. To identify potential targets of androgen signaling in the testis, we have analyzed the transcriptional profile of adult testes from Ar hypomorphs alone or in combination with Sertoli cell-specific Ar ablation. Using Affymetrix MOE430A mouse genome arrays we interrogated more than 22,000 transcripts. We found the expression level of 62 transcripts in the Ar mutants differed by greater than 2-fold compared with wild type. We also found that more transcripts were up-regulated than down-regulated, highlighting AR's role as a transcriptional repressor in the testis. Twelve transcripts were uniquely affected, and 16 transcripts were more severely affected in Sertoli cell-specific Ar ablation compared with hypomorphic Ar mutants. Using a comparative genomic approach, we analyzed the 6 kb around the transcriptional start sites of affected transcripts for conserved AREs (androgen response elements). We identified at least one conserved ARE in 65% of the genes misregulated in our microarray analysis where clear mouse-human orthologs were available. We used a reporter assay in cell culture to functionally verify the AREs for the kallikrein 27 gene. This suggests that the majority of the misregulated transcripts have a high probability of being direct AR targets. The transcripts affected by these Ar mutations encode a diverse array of proteins whose molecular functions support the contention that AR supports spermatogenesis in both a permissive and instructive fashion.
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Affiliation(s)
- Stephen M Eacker
- Department of Genome Sciences, University of Washington School of Medicine, Box 355065, 1705 NE Pacific, Foege Building, Room 133C, Seattle, Washington 98195-5065, USA
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21
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Schuenemann GM, Mendis-Handagama SMLC, Hopkins FM, Kania SA, Schrick FN. Changes in the testis seminiferous tubules and interstitium in prepubertal bull calves immunised against inhibin at the time of gonadotropin administration. Reprod Fertil Dev 2007; 19:840-9. [PMID: 17897587 DOI: 10.1071/rd07003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2007] [Accepted: 06/01/2007] [Indexed: 11/23/2022] Open
Abstract
The aim of the present study was to evaluate the effects of gonadotropin administration at initiation of inhibin passive immunisation in Jersey bull calves (age 27 � 5 days) on testicular morphology and development. Primary treatments consisted of control (keyhole limpet haemocyanin, KLH; n = 9) or immunisation against inhibin (INH; n = 9). Subsets of calves were randomly assigned within primary treatments (TRT) to receive saline ( n = 3 per TRT), follicle-stimulating hormone (FSH; n = 3 per TRT) or gonadotrophin-releasing hormone (GnRH, n = 3 per TRT). The right testis was removed (age 118 � 5 days) to determine volumes of testicular components and cell numbers per testis using stereology. Data were analysed using the MIXED procedure of the SAS program. Antibody titres against inhibin were increased in INH bulls compared with KLH bulls (P < 0.05). In addition, a significant immunisation � hormone treatment interaction was noted for the number of germ cells. Administration of FSH at the time of initial immunisation against inhibin significantly increased the number of germ cells (92.2 � 9 � 106 cells) compared with INH+saline bulls (54.9 � 10 � 106 cells), with INH+GnRH bulls having an intermediate number of cells (64.5 � 9 � 106 cells; P < 0.05). These results suggest that gonadotropin administration at the time of inhibin immunisation increases the number of germ cells in the testis.
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Affiliation(s)
- G M Schuenemann
- Department of Animal Science, Tennessee Agriculture Experiment Station, The University of Tennessee, Knoxville, TN 37996-4574, USA
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Tsai MY, Yeh SD, Wang RS, Yeh S, Zhang C, Lin HY, Tzeng CR, Chang C. Differential effects of spermatogenesis and fertility in mice lacking androgen receptor in individual testis cells. Proc Natl Acad Sci U S A 2006; 103:18975-80. [PMID: 17142319 PMCID: PMC1748162 DOI: 10.1073/pnas.0608565103] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Using a Cre-Lox conditional knockout strategy, we generated a germ cell-specific androgen receptor (AR) knockout mouse (G-AR(-/y)) with normal spermatogenesis. Sperm count and motility in epididymis from AR(-/y) mice are similar to that of WT (G-AR(+/y)) mice. Furthermore, fertility tests show there was no difference in fertility, and almost 100% of female pups sired by G-AR(-/y) males younger than 15 weeks carried the deleted AR allele, suggesting the efficient AR knockout occurred in germ cells during meiosis. Together, these data provide in vivo evidence showing male mice without AR in germ cells can still have normal spermatogenesis and fertility, suggesting the essential roles of AR during spermatogenesis might come from indirect cell-cell communication in a paracrine fashion. We then compared the consequences of AR loss in the spermatogenesis and fertility of G-AR(-/y) mice with two other testicular cell-specific AR(-/y) mice and total AR knockout male mice. The results provide clear in vivo evidence that androgen/AR signaling in Sertoli cells plays a direct important role in spermatogenesis and in Leydig cells plays an autocrine regulatory role to modulate Leydig cell steroidogenic function. Total AR knockout male mice have the most severe defects among these mice. These contrasting data with G-AR(-/y) mice suggest AR might have different roles in the various cells within testis to contribute to normal spermatogenesis and male fertility in mice.
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Affiliation(s)
- Meng-Yin Tsai
- *George H. Whipple Laboratory for Cancer Research, Departments of Urology and Pathology, University of Rochester, Rochester, NY 14642
- Graduate Institute of Clinical Medicine, Chang Gung University, Kaohsiung, Taiwan; and
| | - Shauh-Der Yeh
- *George H. Whipple Laboratory for Cancer Research, Departments of Urology and Pathology, University of Rochester, Rochester, NY 14642
- Graduate Institute of Medical Sciences and Departments of Urology and Gynecology and Obstetrics, Taipei Medical University, Taipei 110, Taiwan
| | - Ruey-Sheng Wang
- *George H. Whipple Laboratory for Cancer Research, Departments of Urology and Pathology, University of Rochester, Rochester, NY 14642
- Graduate Institute of Medical Sciences and Departments of Urology and Gynecology and Obstetrics, Taipei Medical University, Taipei 110, Taiwan
| | - Shuyuan Yeh
- *George H. Whipple Laboratory for Cancer Research, Departments of Urology and Pathology, University of Rochester, Rochester, NY 14642
| | - Caixia Zhang
- *George H. Whipple Laboratory for Cancer Research, Departments of Urology and Pathology, University of Rochester, Rochester, NY 14642
| | - Hung-Yun Lin
- *George H. Whipple Laboratory for Cancer Research, Departments of Urology and Pathology, University of Rochester, Rochester, NY 14642
| | - Chii-Ruey Tzeng
- Graduate Institute of Medical Sciences and Departments of Urology and Gynecology and Obstetrics, Taipei Medical University, Taipei 110, Taiwan
| | - Chawnshang Chang
- *George H. Whipple Laboratory for Cancer Research, Departments of Urology and Pathology, University of Rochester, Rochester, NY 14642
- To whom correspondence should be addressed. E-mail:
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Matthiesson KL, McLachlan RI, O'Donnell L, Frydenberg M, Robertson DM, Stanton PG, Meachem SJ. The relative roles of follicle-stimulating hormone and luteinizing hormone in maintaining spermatogonial maturation and spermiation in normal men. J Clin Endocrinol Metab 2006; 91:3962-9. [PMID: 16895950 DOI: 10.1210/jc.2006-1145] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
CONTEXT Male hormonal contraception via gonadotropin and intratesticular androgen withdrawal disrupts spermatogenesis at two principal sites: 1) spermatogonial maturation, and 2) spermiation. OBJECTIVE The objective of this study was to explore the relative dependence of each stage of germ cell development on FSH and LH/intratesticular androgen action. DESIGN, SETTING, AND PARTICIPANTS Eighteen men enrolled in this prospective, randomized 14-wk study at Prince Henry's Institute. INTERVENTIONS Subjects (n = 6/group) were assigned to 6 wk of 1) testosterone (T) implant (4 x 200 mg sc once)+depot medroxy progesterone acetate (DMPA; 150 mg im once); 2) T implant+DMPA+FSH (300 IU sc twice weekly); and 3) T implant+DMPA+human chorionic gonadotropin (hCG; 1000 IU sc twice weekly as an LH substitute). Men then underwent a vasectomy and testicular biopsy with previously reported control data used for comparison. MAIN OUTCOME MEASURES Germ cell number (assessed by the optical disector stereological approach) and intratesticular androgen levels were determined. RESULTS T+DMPA alone significantly suppressed type B spermatogonia, preleptotene through to pachytene spermatocytes, and round spermatids from control (P < 0.05). All germ cell subtypes were maintained at control levels by either FSH or LH activity, except pachytene spermatocytes, which were found to be lower in the hCG vs. FSH (P < 0.01) and control groups (P < 0.05). CONCLUSIONS FSH and LH maintained spermatogenesis independently in this gonadotropin-suppressed model. Compared with LH, FSH showed better maintenance of pachytene spermatocyte number, whereas improved conversion to round spermatids was suggested with hCG treatment. Future contraceptive treatment strategies must consider independent regulation of spermatogenesis by both FSH and LH/intratesticular androgens for maximum efficacy.
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Affiliation(s)
- Kati L Matthiesson
- Prince Henry's Institute, and Departments of Obstetrics and Gynaecology, Monash University, P.O. Box 5152, Monash Medical Center, Clayton, Victoria 3168, Australia.
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Satterlee DG, Castille SA, Fioretti WC. Active immunization of broiler breeder cockerels against chicken inhibin accelerates puberty and prevents age-induced testicular involution. Poult Sci 2006; 85:1087-94. [PMID: 16776479 DOI: 10.1093/ps/85.6.1087] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Injection of quail and breeder hens with a recombinant protein antigen (MBP-cINA521)--a fusion of the bacterical maltose-binding protein (MBP) and a fragment of the alpha-subunit of chicken inhibin (cINA521)--accelerates puberty and enhances lay. Herein, the effects of this immunogen on reproductive responses in broiler breeder males were assessed. Cockerels were subcutaneously injected with 0 (vehicular controls), 1, 3, or 5 mg of MBP-cINA521 at 13 wk of age and with one-half of these dosages (boosters) at 18 wk. Bird subsamples were weighed, blood sampled, and killed at 24, 28, and 39 wk of age to assess age and vaccination effects on BW, testes weight (TWT), TWT relative to BW (RTWT), TWT > or = 20 g (TWT20; theoretical threshold TWT for maximum fertility), and plasma testosterone. Breeder males are sexually developing, reach peak sexual activity, and show age-related reproductive decline at these ages. Because vaccine gonadal effects at 24 wk appeared to be dramatic, the size of the left testis was also scored to see if size differences could be detected by mere visual inspection. Male fighting increasingly reduced sample sizes beyond 24 wk. Because mortality was unrelated to the treatments and to insure meaningful statistical comparisons, MBP-cINA521 data were pooled. Body weight (P < 0.04), testis score (P < 0.02), TWT (P < 0.03), RTWT (P = 0.06), and plasma testosterone (P = 0.08) were elevated in immunogen-treated males at 24 wk of age, and more (P < 0.05) MBP-cINA521-treated birds than controls achieved a TWT20 at this time. These variables did not differ by treatment at 28 wk. However, by 39 wk, treatment effects reemerged as follows: TWT (P < 0.04), RTWT (P = 0.06), and TWT20 (P < 0.01) were increased in vaccinated males who also showed nearly 3-fold higher levels of plasma testosterone. We conclude that immunoneutralization of inhibin accelerates puberty and retards age-related sexual senescence that typically occurs in broiler breeder males.
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Affiliation(s)
- D G Satterlee
- Applied Animal Biotechnology Laboratories, Department of Animal Sciences, Louisiana State University Agricultural Center, Baton Rouge 70803, USA.
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25
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Medan MS, Watanabe G, Nagura Y, Fujita M, Taya K. Effect of active immunization against inhibin on hormonal concentrations and semen characteristics in Shiba bucks. Theriogenology 2006; 65:691-702. [PMID: 16024069 DOI: 10.1016/j.theriogenology.2005.06.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2005] [Accepted: 06/02/2005] [Indexed: 11/22/2022]
Abstract
Active immunization against inhibin increased ovulation rate in females; in males, the effects of active immunization against inhibin on hormonal concentrations and sperm production need more investigation. To test the hypothesis that active immunization against inhibin increases FSH secretion and sperm output, the present study was undertaken to determine the effects of active immunization against inhibin on hormonal profile and sperm production in Shiba bucks. The bucks were actively immunized against inhibin alpha-subunit (immunized group, n=6) or Freund adjuvant (control group, n=5) four times, at 5-weeks intervals. Blood samples were collected twice-weekly and two successive ejaculates of semen were collected (with an artificial vagina) once-weekly. Plasma concentrations of FSH, LH and testosterone were measured by radioimmunoassay (RIA) and sperm motility characteristics were measured by computer-assisted sperm analysis (CASA). All inhibin-immunized bucks produced antibodies against inhibin. Relative to control bucks, in immunized bucks there were significant increases in plasma FSH concentrations and in sperm concentrations from 5 to 9 weeks and from 8 to 11 weeks, respectively, after primary immunization. However, plasma concentrations of LH and testosterone, semen volume, percentage of motile spermatozoa and motility parameters (straight-line velocity, curvilinear velocity and linearity index) were similar in both groups. In conclusion, active immunization against inhibin alpha-subunit increased FSH secretions and enhanced sperm production in bucks, whereas LH and testosterone concentrations, semen volume and sperm motility parameters were unaffected. Active immunization against inhibin could be used to improve fertility in Shiba bucks.
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Affiliation(s)
- M S Medan
- Laboratory of Veterinary Physiology, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan
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Shetty G, Weng CCY, Meachem SJ, Bolden-Tiller OU, Zhang Z, Pakarinen P, Huhtaniemi I, Meistrich ML. Both testosterone and follicle-stimulating hormone independently inhibit spermatogonial differentiation in irradiated rats. Endocrinology 2006; 147:472-82. [PMID: 16210366 DOI: 10.1210/en.2005-0984] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Simultaneous suppression of both testosterone and FSH with GnRH antagonists (GnRH-ant) reverses the radiation-induced block in spermatogonial differentiation in F1 hybrids of Lewis and Brown-Norway rats. Although addition of exogenous testosterone restores the block, it also raises FSH, and hence it had not been possible to conclusively determine which hormone was inhibiting spermatogonial differentiation. In the present study, we establish the relative roles of testosterone and FSH in this inhibition using three different approaches. The first approach involved the treatment of irradiated rats, in which differentiation was stimulated by GnRH-ant plus flutamide, with FSH for 2 wk; the FSH reduced the percentage of tubules that were differentiated (TDI) by about 2-fold, indicating that FSH does have an inhibitory role. The second approach involved treatment of irradiated, hypophysectomized rats with exogenous testosterone for 10 wk; testosterone also reduced the TDI, demonstrating that testosterone had a definite inhibitory effect, independent of pituitary hormones. Furthermore, in this protocol we showed that TDI in the hypophysectomized testosterone-treated group, which had higher intratesticular testosterone levels but lacked FSH, was slightly higher than the TDI in a GnRH-antagonist-testosterone-treated group of irradiated rats, which had normal physiological levels of FSH; this result supports a role for endogenous FSH in suppressing spermatogonial differentiation in the latter group. The third approach involved injection of an active anti-FSH antibody for 10 d in untreated, GnRH-ant plus flutamide-treated, or GnRH-ant plus testosterone-treated irradiated rats. This was not sufficient to increase the TDI. However, flutamide given in a similar treatment schedule did increase the TDI in GnRH-ant plus testosterone-treated rats. We conclude that both testosterone and FSH individually inhibit spermatogonial differentiation after irradiation, but testosterone is a more highly potent inhibitor than is FSH.
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Affiliation(s)
- Gunapala Shetty
- Department of Experimental Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
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Meng J, Holdcraft RW, Shima JE, Griswold MD, Braun RE. Androgens regulate the permeability of the blood-testis barrier. Proc Natl Acad Sci U S A 2005; 102:16696-700. [PMID: 16275920 PMCID: PMC1283811 DOI: 10.1073/pnas.0506084102] [Citation(s) in RCA: 294] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Within the mammalian testis, specialized tight junctions between somatic Sertoli cells create basal and apical polarity within the cells, restrict movement of molecules between cells, and separate the seminiferous epithelium into basal and adluminal compartments. These tight junctions form the basis of the blood-testis barrier, a structure whose function and dynamic regulation is poorly understood. In this study, we used microarray gene expression profiling to identify genes with altered transcript levels in a mouse model for conditional androgen insensitivity. We show that testosterone, acting through its receptor expressed in Sertoli cells, regulates the expression of claudin 3, which encodes a transient component of newly formed tight junctions. Sertoli cell-specific ablation of androgen receptor results in increased permeability of the blood-testis barrier to biotin, suggesting claudin 3 regulates the movement of small molecules across the Sertoli cell tight junctions. These results suggest that androgen action in Sertoli cells regulates germ cell differentiation, in part by controlling the microenvironment of the seminiferous epithelium. Our studies also indicate that hormonal strategies for male contraception may interfere with the blood-testis barrier.
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Affiliation(s)
- Jing Meng
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
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Abstract
Proper functioning of the mammalian testis is dependent upon an array of hormonal messengers acting through endocrine, paracrine, and autocrine pathways. Within the testis, the primary messengers are the gonadotrophins, follicle stimulating hormone and luteinizing hormone, and the androgens. Abundant evidence indicates that the role of the gonadotrophins is to maintain proper functioning of testicular somatic cells. It is the androgens, primarily testosterone, which act through the somatic cells to regulate germ cell differentiation. Despite extensive research in this area, little is known about the cell-specific requirements for androgens and even less is understood about the downstream effectors of androgen signalling. However, recent work using cell-specific ablation of androgen receptor function has demonstrated a clear requirement for androgen signalling at multiple, discrete time points during spermatogenesis. These models also provide useful tools for identifying the targets of androgen receptor activity. The purpose of this review is to provide a brief overview of recent advances in our understanding of hormonal regulation of spermatogenesis, with an emphasis on the role of testosterone within the testis, and to pose important questions for future research in this field.
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Affiliation(s)
- Robert W Holdcraft
- University of Washington, School of Medicine, Department of Genome Sciences, 1959 NE Pacific Street, Seattle, WA 98195-7730, USA
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29
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Wagner A, Claus R. Involvement of glucocorticoids in testicular involution after active immunization of boars against GnRH. Reproduction 2004; 127:275-83. [PMID: 15056793 DOI: 10.1530/rep.1.00072] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Active GnRH immunization of boars inhibits LH and testicular steroids but the consequences for spermatogenesis are unknown. Six boars were immunized three times against GnRH at 20, 24 and 28 weeks. Another six boars served as controls. Plasma LH and FSH were determined at 28 and 31 weeks. Testosterone and cortisol were determined before killing the pigs at 32 weeks. Tissue samples were taken for histology and fluid from the seminiferous tubuli for steroid determination. Individual germ cells were counted in histological sections. The glucocorticoid receptor (GCR), mitosis of spermatogonia and apoptosis were characterized by immunocytochemistry. Immunization reduced LH and testosterone to base levels whereas FSH was not changed. Testis weight was reduced by 64% due to a loss of Leydig cell cytoplasm (90.3%) and a decrease of tubule diameters (60.6%). Except for A-spermatogonia, all other spermatogenic cells were reduced by about 60%. Mitosis was reduced in immunized boars. Expression of GCRs was limited to spermatogonia and differed between immunized boars (8% of spermatogonia) and controls (2%). In the controls, androgen concentrations in tubular fluid were tenfold higher compared with immunized boars. Cortisol concentrations were of the order of 40 nmol/l both in the tubular fluid and blood plasma. These concentrations did not differ between groups. Apoptosis occurred only in spermatogonia and pachytene spermatocytes and was twofold higher in immunized boars compared with controls. Thus the availability of glucocorticoids in the tubuli and the expression of GCRs initiate apoptosis, which in turn reduces sperm yield. Testosterone is known to be an inhibitor of GCR expression, thus increasing the efficiency of spermatogenesis.
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Affiliation(s)
- A Wagner
- Universität Hohenheim, Institut für Tierhaltung und Tierzüchtung, Fachgebiet Tierhaltung und Leistungsphysiologie (470A), Garbenstr. 17, 70599 Stuttgart, Germany
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Jeyaraj DA, Grossman G, Petrusz P. Dynamics of testicular germ cell apoptosis in normal mice and transgenic mice overexpressing rat androgen-binding protein. Reprod Biol Endocrinol 2003; 1:48. [PMID: 12831397 PMCID: PMC165588 DOI: 10.1186/1477-7827-1-48] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2003] [Accepted: 06/12/2003] [Indexed: 11/17/2022] Open
Abstract
The number and type of testicular germ cells undergoing apoptosis in different age groups of mice (from 7 to 360 days of age) was determined and compared in age-matched wild type (WT) control and in a transgenic (TG) mice homozygous to rat androgen binding protein (ABP) using flow cytometry. Flow cytometric quantification revealed that the total number of germ cells undergoing apoptosis did not differ significantly in WT and TG mice up to Day 14. From Day 21 to Day 60, the number of germ cells undergoing apoptosis was consistently higher in TG than in WT mice. Starting from Day 90, the number of germ cells undergoing apoptosis in TG mice was lower than controls until Day 360. In 21-60 days old TG mice, spermatogonia, S-Phase cells, and primary spermatocytes are the cell types undergoing apoptosis at significantly greater numbers than those in WT mice. However, starting from day 60, the total number of spermatids undergoing apoptosis was significantly lower in TG mice than in age-matched WT controls. TdT-mediated dUTP-biotin nick end labeling (TUNEL) in testicular sections from TG mice of 21 and 30 days of age confirmed the presence of increased numbers of apoptotic germ cells compared to their age matched controls. These data indicate that the continuous presence of greater than physiological concentrations of ABP in the mouse testis has a biphasic effect on the frequency of apoptosis in germ cells. The initial pre-pubertal increase in testicular germ cell apoptosis may result from direct or indirect actions of ABP and is likely to determine the subsequent life-death balance of germ cell populations in TG mice, whereas the subsequent reduction may result from maturation depletion. A wave of apoptosis during the pre-pubertal period is required for normal spermatogenesis to develop, and our data indicate that this apoptotic wave may be regulated by ABP and/or androgens.
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Affiliation(s)
- D Antony Jeyaraj
- Department of Cell and Developmental Biology and Laboratories for Reproductive Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Gail Grossman
- Department of Cell and Developmental Biology and Laboratories for Reproductive Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Peter Petrusz
- Department of Cell and Developmental Biology and Laboratories for Reproductive Biology, University of North Carolina, Chapel Hill, NC 27599, USA
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Matsuzaki S, Uenoyama Y, Okuda K, Watanabe G, Kitamura N, Taya K, Cruzana MB, Yamada J. Prepubertal changes in immunoreactive inhibin concentration in blood serum and testicular tissue in Holstein bull calves. J Vet Med Sci 2001; 63:1303-7. [PMID: 11789608 DOI: 10.1292/jvms.63.1303] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Age-related changes in immunoreactive inhibin (ir-inhibin) levels and the relationship among ir-inhibin, gonadotropins and testosterone were examined in 53 Holstein bull calves from neonates to 8.6 months old. Serum levels of ir-inhibin, luteinizing hormone (LH), follicle stimulating hormone (FSH) and testosterone, as well as ir-inhibin levels in testicular extracts, and testicular sizes were measured. All hormones were measured by specific radioimmunoassays. The concentrations of ir-inhibin in serum and testicular tissue were high in neonatal calves and tended to decrease with age. In contrast, serum concentrations of gonadotropins did not show any age-related changes within the experimental period. Serum testosterone levels and testicular sizes (length, width and weight) were positively correlated with age. Furthermore, a positive immunostaining to antiserum for the inhibin alpha-subunit was immunocytochemically observed only in Sertoli cells of the seminiferous tubules from neonates to calves less than 6 months old. These results indicate that the immature bovine testis produces and secretes high levels of ir-inhibin and that the Sertoli cells are a major source of ir-inhibin in prepubertal bull calves.
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Affiliation(s)
- S Matsuzaki
- Department of Veterinary Anatomy, Obihiro University of Agriculture and Veterinary Medicine, Japan
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Wakayama T, Ohashi K, Mizuno K, Iseki S. Cloning and characterization of a novel mouse immunoglobulin superfamily gene expressed in early spermatogenic cells. Mol Reprod Dev 2001; 60:158-64. [PMID: 11553913 DOI: 10.1002/mrd.1072] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We cloned and characterized a novel immunoglobulin superfamily gene from the cDNA library of adult mouse testis. This gene was expressed in the spermatogenic cells and hence termed SgIGSF. The predicted SgIGSF protein was composed of 445 amino-acid residues and contained a signal peptide, three extracellular immunoglobulin (Ig)-like domains, a transmembranous domain, and a cytoplasmic domain. SgIGSF mRNA consisted of two size species, 2.1- and 4.5-kb in length. Besides testis, SgIGSF mRNA was also expressed in a variety of organs, including the cerebrum, liver, kidney, and epididymis. The testis and liver expressed both the 2.1- and 4.5-kb transcripts, whereas the cerebrum and epididymis predominantly expressed the 4.5-kb one. In situ hybridization analysis in testis revealed that SgIGSF mRNA signal was localized to the spermatogenic cells from spermatogonia to zygotene spermatocytes. These results suggested that SgIGSF occurs in the plasma membrane of spermatogenic cells during the earlier stages of spermatogenesis.
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Affiliation(s)
- T Wakayama
- Departmemt of Anatomy, School of Medicine, Kanazawa University, Kanazawa, Japan.
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Ottenweller JE, Li MT, Giglio W, Anesetti R, Pogach LM, Huang HF. Alteration of follicle-stimulating hormone and testosterone regulation of messenger ribonucleic acid for Sertoli cell proteins in the rat during the acute phase of spinal cord injury. Biol Reprod 2000; 63:730-5. [PMID: 10952914 DOI: 10.1095/biolreprod63.3.730] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The detrimental effects of spinal cord injury (SCI) on spermatogenesis in the rat can be attenuated by exogenous testosterone (T) but enhanced by exogenous follicle-stimulating hormone (FSH). These results suggest that T-dependent cellular events may be involved in testicular injury after SCI and that such events may be associated with modification of FSH effects on Sertoli cell function. The current study compared the responses of Sertoli cells to exogenous T and FSH after SCI or sham surgery using steady-state levels of Sertoli cell protein mRNA transcripts as markers of responsiveness. Rats underwent sham surgery or SCI and then were treated for 7 or 14 days with T-filled silastic capsules (2 x 5 cm) and/or daily injections of 0.1 units of porcine FSH. Vehicle-treated control rats received 5-cm empty capsules and daily injections of saline vehicle. Two weeks after sham surgery, levels of mRNA for the androgen receptor (AR), FSH receptor (FSHR), androgen-binding protein (ABP), or sulfated glycoprotein (SGP)-2 in the testis were unaffected by T or FSH alone. Testosterone alone, however, significantly decreased transferrin (Trf) mRNA levels in the testis (P: < 0.01). The combination of T and FSH treatments resulted in significant decreases in levels of the above transcripts (P: < 0.05; P: < 0.01). Seven days after SCI, the testes of vehicle-treated SCI rats had higher levels of AR and SGP-2 mRNA than did those of sham control rats (P: < 0.01); such effects were transient and disappeared by Day 14 post-SCI. Testosterone treatment of SCI rats for 7 days resulted in decreases in mRNA levels for AR and Trf in the testes (P: < 0.01) but increased testicular levels of mRNAs for FSHR and SGP-2 in SCI rats. Follicle-stimulating hormone treatment for 7 days prevented the increase in AR mRNA that was seen in the testis of untreated SCI rats and increased levels of ABP and SGP-2 mRNAs in SCI rats (P: < 0.01). Follicle-stimulating hormone treatment of SCI rats did not affect FSHR mRNA levels by itself, but it blocked the stimulatory effect of T on FSHR and SGP-2 mRNAs. Fourteen days after SCI, testicular AR mRNA levels were not affected by T alone, but they increased in those rats that received FSH with or without concurrent T treatments (P: < 0.05). In contrast to their effects in sham control rats, T or FSH alone or in combination resulted in significant increases in testicular levels of ABP, SGP-2, and FSHR mRNAs (P: < 0.05). At this time, Trf mRNA in the testis of SCI rats was also suppressed by T (P: < 0.05), as it did in sham control rats, but Trf mRNA was increased by the FSH (P: < 0.01) that had inhibited this transcript in the testes of sham control rats. The effects of FSH on the Sertoli cell transcripts in SCI rats were either attenuated or blocked when T was given concurrently. In addition, testicular and serum T levels in those SCI rats that received FSH (alone or in combination with T) for 14 days were significantly increased, an effect that was not seen after sham surgery. These findings demonstrate that hormonal regulation of both Sertoli and Leydig cells was altered during the acute phase of SCI. Such changes may modify the functions of both cell types, thereby affecting the endocrine and/or paracrine microenvironment within the seminiferous epithelium. These effects could impair the functional capacity of Sertoli cells and contribute to impairment of spermatogenesis after SCI.
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Affiliation(s)
- J E Ottenweller
- Veterans Affair Medical Center, East Orange, New Jersey 07019, USA
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Ebling FJ, Brooks AN, Cronin AS, Ford H, Kerr JB. Estrogenic induction of spermatogenesis in the hypogonadal mouse. Endocrinology 2000; 141:2861-9. [PMID: 10919273 DOI: 10.1210/endo.141.8.7596] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abnormal sperm production and reduced fertility have been reported in transgenic male mice lacking the alpha-subtype of the estrogen receptor (ER)alpha or aromatase. The aim of this study was to investigate the role of estrogen in male reproductive function, by determining the effect of estradiol on testicular function in hypogonadal (hpg) mice congenitally lacking gonadotropin; and thus, sex steroid production. hpg mice were treated, at 2-3 months of age, with slow-release estradiol implants, which achieved circulating estradiol concentrations of approximately 40 pg/ml. Treatment for 35 days reliably induced a 4- to 6-fold increase in testicular weight, compared with the vestigial testes in the untreated or cholesterol-treated controls. The degree of testicular growth after 35 days was similar to that in hpg mice receiving an intrahypothalamic graft of preoptic area tissue taken from neonatal mice on the day of birth, a procedure known to induce testicular development in hpg mice by activation of the pituitary gland. Histological analysis revealed that the testes contained elongated spermatids after 35 days of estradiol treatment, whereas germ cell development never progressed beyond the pachytene stage in control hpg mice. Treatment for 70 days induced full qualitatively normal spermatogenesis in hpg mice. Testis weight increased 5-fold, reflecting a 5-fold increase in total seminiferous tubule volume and a 4- to 5-fold increase in the total volume of the seminiferous epithelium. In all experiments, spermatogenesis proceeded in the absence of measurable androgen concentrations, but circulating FSH concentrations were slightly (but significantly) elevated, relative to cholesterol-treated control hpg mice. This stimulatory action of estradiol on FSH secretion was unexpected, particularly because identical estradiol treatments significantly decreased serum FSH levels in wild-type littermates. These results indicate that estrogens may play a role in spermatogenesis, via stimulatory effects on FSH secretion. An alternative or complementary explanation, given the recent identification of estrogen receptors (ERalpha and ERbeta) and aromatase within various cell types in the testis, is that estrogens exert paracrine actions within the testis to promote spermatogenesis. The identification of effects of estradiol on testicular function provides a conceptual basis to reexamine the speculative link between increased exposure to environmental estrogens and reduced fertility in man.
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Affiliation(s)
- F J Ebling
- School of Biomedical Sciences, University of Nottingham Medical School, Queen's Medical Centre, United Kingdom.
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Shetty G, Wilson G, Huhtaniemi I, Shuttlesworth GA, Reissmann T, Meistrich ML. Gonadotropin-releasing hormone analogs stimulate and testosterone inhibits the recovery of spermatogenesis in irradiated rats. Endocrinology 2000; 141:1735-45. [PMID: 10803584 DOI: 10.1210/endo.141.5.7446] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We investigated the effects of GnRH analogs, different doses of testosterone (T), an androgen receptor antagonist (flutamide), and combinations of these on the recovery of spermatogenesis after irradiation. Treatment with a GnRH agonist (Lupron) for 10 weeks after irradiation reduced the intratesticular T concentration (ITT) to 4% of that in irradiated rats and serum FSH to undetectable levels without altering serum LH levels. Injection of a GnRH antagonist (Cetrorelix) at 3 weeks after irradiation suppressed LH, FSH, and ITT to <7%, 32%, and 10%, respectively, of levels in irradiated-only rats within 2 weeks; suppression was maintained for approximately 3 to 4 weeks. The percentage of tubules with differentiated germ cells (repopulation index, RI) was <0.6% at weeks 10 to 20 after irradiation. Spermatogenic recovery was induced by both the GnRH agonist (RI = 58% at week 10; 91% at week 20) and antagonist (RI = 70% at week 13). There was a dose-dependent suppression of testicular germ cell repopulation when T was combined with GnRH analogs. The ability of T to abolish the spermatogenic stimulatory effect of the GnRH antagonist was evident by the similar RI obtained for irradiated rats given antagonist + T or T alone. This suppression of GnRH-induced recovery of spermatogenesis by T could be reversed by flutamide. The RI best correlated with the degree of ITT suppression. In ITT-suppressed rats, the RI also showed an inverse correlation with serum T levels. Thus, T and/or its androgenic metabolites either directly or indirectly inhibit spermatogenic recovery after irradiation through an androgen receptor-mediated process. In addition, there was a close negative correlation between RI and FSH levels, and hence, a spermatogenic inhibitory role for FSH in the irradiated rats cannot be ruled out.
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Affiliation(s)
- G Shetty
- Department of Experimental Radiation Oncology, The University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
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MATSUZAKI S, UENOYAMA Y, OKUDA K, WATANABE G, KITAMURA N, TAYA K, YAMADA J. Age-Related Changes in the Serum Levels of Inhibin, FSH, LH and Testosterone in Holstein Bulls. J Reprod Dev 2000. [DOI: 10.1262/jrd.46.245] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Sigenori MATSUZAKI
- Department of Veterinary Anatomy, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Japan
- Hokkaido Livestock Improvement Association Inc., Shimizu-cho, Kamikawa-gun 089-0103, Hokkaido, Japan
| | - Yoshihisa UENOYAMA
- Laboratory of Reproductive Endocrinology, Okayama University, Okayama 700-8530, Japan
| | - Kiyoshi OKUDA
- Laboratory of Reproductive Endocrinology, Okayama University, Okayama 700-8530, Japan
| | - Gen WATANABE
- Laboratory of Veterinary Physiology, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
| | - Nobuo KITAMURA
- Department of Veterinary Anatomy, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Japan
| | - Kazuyoshi TAYA
- Laboratory of Veterinary Physiology, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan
| | - Junzo YAMADA
- Department of Veterinary Anatomy, Obihiro University of Agriculture and Veterinary Medicine, Obihiro 080-8555, Japan
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Bame JH, Dalton JC, Degelos SD, Good TE, Ireland JL, Jimenez-Krassel F, Sweeney T, Saacke RG, Ireland JJ. Effect of long-term immunization against inhibin on sperm output in bulls. Biol Reprod 1999; 60:1360-6. [PMID: 10330093 DOI: 10.1095/biolreprod60.6.1360] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
To determine the effect of neutralization of inhibin on sperm output, 12 Holstein bulls were paired by birth date and weight on Day 1 of age. Each bull was actively immunized against bovine inhibin alpha1-26 gly-tyr (bINH) conjugated to human alpha globulin (HAG, n = 6 bulls) or HAG alone (controls, n = 6) at 60 days of age; booster immunizations were administered at 90, 104, 124, 270, and 395 days of age. Body weights and scrotal circumferences were measured at the time of primary immunization and at 10 days after each booster. In addition, jugular blood was obtained at 60, 70, 100, 114, 134, 280, and 405 days of age, during the 3-wk sperm collection period, and during a 6-h blood-sampling period after sperm collection to determine bINH antibody titer and concentrations of FSH, LH, testosterone, and estradiol. Beginning at 405 days of age, sperm output was measured 3 days/wk for 3 wk with two successive ejaculates collected each day for a total of 18 ejaculates per bull. During Days 60-405 of age, the increase in titer of bINH antibodies, scrotal circumference, and serum concentration of FSH was greater (p < 0.01) for the bINH-immunized compared with control bulls. There were significant (p < 0.01) pair x treatment interactions for sperm output and serum FSH and LH concentrations. Specifically, bINH-immunized bulls for four of the six pairs had nearly 50% greater serum FSH concentrations and sperm output. For the remaining two pairs, sperm output was lower and FSH was either lower or only marginally higher in the bINH-immunized bulls compared with controls. Also, the control bulls for the two remaining pairs produced more sperm than all but one bINH-immunized bull, and had markedly higher serum LH concentrations than all other bulls. To summarize, enhancement of sperm output after immunization against inhibin depends on the subsequent increment in FSH concentrations. We conclude that inhibin suppresses spermatogenesis. Thus, methods to immunoneutralize inhibin may have merit as a therapeutic route to enhance sperm production in reproductively maturing bulls.
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Affiliation(s)
- J H Bame
- Department of Dairy Science, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
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Affiliation(s)
- A Revelli
- Department of Obstetrical and Gynecological Sciences, University of Torino, Italy
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Morris ID, Lendon RG, Waters C, Naylor G, Jones N. Thymic regression and apoptosis in the rat after treatment with the Leydig cell cytotoxin ethylene dimethanesulphonate (EDS). Toxicology 1997; 120:19-27. [PMID: 9160105 DOI: 10.1016/s0300-483x(97)03626-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Ethylene dimethanesulphonate (EDS) is an alkylating agent which is widely assumed to specifically kill Leydig cells leaving other biological systems intact. However, after EDS treatment of the male rat the thymus reversibly involutes and the gonadal regional lymph nodes are activated. In the present experiments we have demonstrated that EDS has a direct action upon the thymus both in vivo and in vitro. EDS treatment of the intact and castrated male rat and the intact female rat caused regression of the thymus by up to 50% 3 days later. Total cellularity decreased while the proliferative index increased suggesting a compensatory mechanism. Thymocytes were exposed to EDS in vitro and the response compared to the glucocorticoid methylprednisolone (P), a well characterised thymic apoptotic stimulant. EDS and P increased apoptosis in the thymocyte as characterised by the appearance of cells containing nuclei with apoptotic morphology and with DNA fragmentation visualised by a characteristic ladder after agarose gel electrophoresis. The effects of both EDS and P were time and dose dependent but, in contrast to the effects in Leydig cells, P was the most effective apoptotic stimulus (for instance 100%-P compared to 30%-EDS or 7% control/DMSO after 24 h incubation). The immunological responses of the gonadal lymph nodes were not associated with testicular regression as it was seen in the castrated rat but may be related to a direct action upon the epididymis. In conclusion, tissue specificity of the Leydig cell cytotoxin needs to be extended to the thymus and epididymis. The mode of cell death in Leydig cells and thymocytes after both glucocorticoids and EDS is apoptosis which suggests that they possess some common mechanism(s) which is responsible for the toxicity of these diverse compounds.
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Abstract
FSH and testosterone (T) secretion are essential for the successful completion of spermatogenesis. Because there are no receptors for FSH or testosterone on germ cells, there are intermediate steps in this action, the nature of which are unknown. However, as the Sertoli cell contains receptors for both FSH and T, it is likely that these hormones exert their influence on germ cells by modulating Sertoli cell function. Both FSH and T exert synergistic actions on germ cells, but T has a specific action on the later stages of spermatid maturation. FSH, by its ability to stimulate Sertoli cell mitosis during testicular development, can influence the spermatogenic capacity of the adult testis.
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Affiliation(s)
- R I McLachlan
- Prince Henry's Institute of Medical Research Clayton, Victoria, Australia
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Weinbauer GF, Nieschlag E. Gonadotrophin control of testicular germ cell development. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1995; 377:55-65. [PMID: 7484447 DOI: 10.1007/978-1-4899-0952-7_4] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Successful and complete male germ cell development is dependent on the balanced, endocrine interplay of the hypothalamus, the pituitary and the testis. The hypothalamus secretes gonadotrophin-releasing hormone in a pulsatile manner which, in turn, elicits the pulsatile release of the gonadotrophins LH and FSH from the pituitary. Luteinizing hormone stimulates spermatogenesis indirectly via testosterone, whereas FSH acts directly on the seminiferous tubules. The synthesis and release of gonadotrophic hormones is under the feedback control of testosterone. Whether other testicular peptides such as inhibin and activin are also involved is not yet clear. Luteinizing hormone/testosterone and FSH are the prime regulators of germ cell development. On their own, these hormones are capable of exerting clear-cut stimulatory effects on the spermatogenic process. However, the quantitative production of spermatozoa generally requires the presence of both LH/testosterone and FSH. Since receptors for androgens and FSH are confined to the somatic cells of the testis, the trophic effects of these hormones on germ cells must be indirect. However, it is not known as yet precisely which genes/factors mediate the beneficial effects of androgens and FSH on spermatogenesis. The gonadotrophic hormones have been found in a number of isoforms and multiple transcripts of the LH and FSH receptor have been detected. Therefore, the possibility must be considered that certain forms of male infertility could be due to dysfunctional hormones and/or mutated receptors.
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Affiliation(s)
- G F Weinbauer
- Institute of Reproductive Medicine of the University, Münster, Germany
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Itoh N, Nanbu A, Tachiki H, Akagashi K, Nitta T, Mikuma N, Tsukamoto T, Kumamoto Y. Restoration of testicular transferrin, insulin-like growth factor-1 (IGF-1), and spermatogenesis by exogenously administered purified FSH and testosterone in medically hypophysectomized rats. ARCHIVES OF ANDROLOGY 1994; 33:169-77. [PMID: 7857168 DOI: 10.3109/01485019408987821] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
To investigate the relation between testicular transferrin and insulin-like growth factor-1 (IGF-1) secreted by Sertoli cells and the differentiation of germ cells in the rat, testosterone and/or purified FSH was administered to rats medically hypophysectomized by an LH-RH agonist. Spermatogenesis was quantitatively analyzed and concentrations of intratesticular transferrin and IGF-1 were measured by radioimmunoassays. The last step of spermatogenesis was quantitatively restored by combined administration of testosterone and purified FSH. Intratesticular IGF-1 concentrations were significantly increased by combined administration of testosterone and purified FSH. From these observations, it is surmised that IGF-1 may have a stimulatory effect on the last step of spermatogenesis.
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Affiliation(s)
- N Itoh
- Department of Urology, Sapporo Medical University School of Medicine, Japan
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de França LR, Jackson A, Russell LD. Hormone sensitivity of germ cells in stage XIV and in stage I of the rat spermatogenic cycle. Tissue Cell 1994; 26:375-83. [PMID: 8073417 DOI: 10.1016/0040-8166(94)90021-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Previous data have been inconclusive with respect to whether the meiotic degenerations that occur in stage XIV of the spermatogenic cycle are increased after hypophysectomy. Meiotic cell degenerations in Stage XIV and early Stage I of the spermatogenic cycle were enumerated to determine if the advanced generation of meiotic cells were influenced by hormonal deprivation subsequent to hypophysectomy and, if so, could cellular degenerations be prevented by supplementation with either testosterone or recombinant FSH during the period of hypophysectomy. The animals utilized were either pituitary-intact rats or rats hypophysectomized for 3 or 10 days. Hormone supplementation began at day 3 post-hypophysectomy and continued until day 10 at which time all animals were sacrificed. The numbers of degenerating meiotic figures (metaphase to telophase of the first and second meiotic division) as expressed per Sertoli cell nucleus or nucleolus were not increased significantly 10 days after hypophysectomy as compared with animals hypophysectomized for 3 days or with pituitary-intact controls. Exogenously administered testosterone and FSH had no effect on the numbers of degenerating meiotic germ cells in hypophysectomized animals. These data indicate that stage XIV metaphase to telophase spermatocytes are not hormone sensitive. However, it was determined that there were new cell types degenerating at Stage XIV and I of the spermatogenic cycle. These were interphase secondary spermatocytes and step 1 spermatids and were seen in stages XIV and I, respectively. These cell degenerations were found in low numbers in Stage XIV and I in either FSH-treated or testosterone-treated rats, suggesting their hormone sensitivity. Thus it is possible that Stages XIV and I are hormone sensitive stages.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- L R de França
- Department of Physiology, Southern Illinois University, School of Medicine, Carbonadale 62901-6512
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44
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Abstract
The autosomal recessive murine mutation weaver (wv) affects postnatal differentiation in at least three neuronal populations in the brain: dopamine-containing neurons in the mid-brain, and granule and Purkinje cells in the cerebellum. Neuronal populations vulnerable to the actions of weaver die in the midst of development. In addition, homozygous weaver males are sterile. We show by a histological analysis of epididymides and testes that the cause of male sterility in weaver is lack of sperm. The epididymides of the adult weaver mice examined were devoid of sperm, and few seminiferous tubules in the adult weaver's testes contained elongated spermatids. Most tubules were marked by moderate to severe degeneration of the seminiferous epithelium. A developmental study showed that the mutant phenotype emerged after the third postnatal week. By postnatal day 28, the development of weaver sperm lagged behind that of the wild-type and some seminiferous tubules contained degenerating germ cells. By postnatal day 35, terminal differentiation of spermatids appeared to be arrested in many tubules and degeneration of the seminiferous epithelium was widespread. The heterozygotes were unaffected at all ages sampled. We conclude that the normal allele at the weaver locus is necessary for spermiogenesis and the maintenance of spermatogenesis.
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Affiliation(s)
- S M Harrison
- Department of Anatomy and Cell Biology, Tufts University School of Medicine, Boston, Massachusetts 02111
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