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Sertoli cell-conditioned medium restores spermatogenesis in azoospermic mouse testis. Cell Tissue Res 2019; 379:577-587. [PMID: 31494714 DOI: 10.1007/s00441-019-03092-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 08/07/2019] [Indexed: 10/26/2022]
Abstract
The current study evaluates potential applications of Sertoli cell (SC)-conditioned medium (CM) and explores the effects of the conditioned medium on the spermatogenesis process in azoospermic mice. For this study, 40 adult mice (28-30 g) were divided into 4 experimental groups: (1) control, (2) DMSO 2% (10 μl), (3) busulfan (40 mg/kg single dose) and (4) busulfan/CM (10 μl). SCs were isolated from 4-week-old mouse testes. After using anesthetics, 10 μl of CM was injected over 3-5 min into each testis and subsequently, sperm samples were collected from the tail of the epididymis. Afterward, the animals were euthanized and testis samples were taken for histopathology experiments and RNA extraction in order to examine the expression of c-kit, STRA8 and PCNA genes. The data showed that CM notably increased the total sperm count and the number of testicular cells, such as spermatogonia, primary spermatocytes, round spermatids, SCs and Leydig cells compared with the control, DMSO and busulfan groups. Furthermore, the results showed that expression of c-kit and STRA8 was significantly decreased in the busulfan and busulfan/SC groups at 8 weeks after the last injection (p < 0.001) but no significant difference was found for PCNA compared with the control and DMSO groups (p < 0.05). These findings suggest that the Sertoli cell-conditioned medium may be beneficial as a practical approach for therapeutic strategies in reproductive and regenerative medicine.
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Namwanje M, Brown CW. Activins and Inhibins: Roles in Development, Physiology, and Disease. Cold Spring Harb Perspect Biol 2016; 8:cshperspect.a021881. [PMID: 27328872 DOI: 10.1101/cshperspect.a021881] [Citation(s) in RCA: 148] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Since their original discovery as regulators of follicle-stimulating hormone (FSH) secretion and erythropoiesis, the TGF-β family members activin and inhibin have been shown to participate in a variety of biological processes, from the earliest stages of embryonic development to highly specialized functions in terminally differentiated cells and tissues. Herein, we present the history, structures, signaling mechanisms, regulation, and biological processes in which activins and inhibins participate, including several recently discovered biological activities and functional antagonists. The potential therapeutic relevance of these advances is also discussed.
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Affiliation(s)
- Maria Namwanje
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
| | - Chester W Brown
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030 Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030 Texas Children's Hospital, Houston, Texas 77030
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Makanji Y, Zhu J, Mishra R, Holmquist C, Wong WPS, Schwartz NB, Mayo KE, Woodruff TK. Inhibin at 90: from discovery to clinical application, a historical review. Endocr Rev 2014; 35:747-94. [PMID: 25051334 PMCID: PMC4167436 DOI: 10.1210/er.2014-1003] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
When it was initially discovered in 1923, inhibin was characterized as a hypophysiotropic hormone that acts on pituitary cells to regulate pituitary hormone secretion. Ninety years later, what we know about inhibin stretches far beyond its well-established capacity to inhibit activin signaling and suppress pituitary FSH production. Inhibin is one of the major reproductive hormones involved in the regulation of folliculogenesis and steroidogenesis. Although the physiological role of inhibin as an activin antagonist in other organ systems is not as well defined as it is in the pituitary-gonadal axis, inhibin also modulates biological processes in other organs through paracrine, autocrine, and/or endocrine mechanisms. Inhibin and components of its signaling pathway are expressed in many organs. Diagnostically, inhibin is used for prenatal screening of Down syndrome as part of the quadruple test and as a biochemical marker in the assessment of ovarian reserve. In this review, we provide a comprehensive summary of our current understanding of the biological role of inhibin, its relationship with activin, its signaling mechanisms, and its potential value as a diagnostic marker for reproductive function and pregnancy-associated conditions.
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Affiliation(s)
- Yogeshwar Makanji
- Department of Obstetrics and Gynecology (Y.M., J.Z., C.H., W.P.S.W., T.K.W.), Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60610; Center for Molecular Innovation and Drug Discovery (R.M., C.H.), Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208; and Department of Molecular Biosciences (N.B.S., K.E.M., T.K.W.), Center for Reproductive Science, Northwestern University, Evanston, Illinois 60208
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Hedger MP, Winnall WR. Regulation of activin and inhibin in the adult testis and the evidence for functional roles in spermatogenesis and immunoregulation. Mol Cell Endocrinol 2012; 359:30-42. [PMID: 21964464 DOI: 10.1016/j.mce.2011.09.031] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 09/16/2011] [Accepted: 09/16/2011] [Indexed: 02/03/2023]
Abstract
Activin A provides a unique link between reproduction and immunity, which is especially significant in the adult testis. This cytokine, together with inhibin B and follistatin acting as regulators of activin A activity, is fundamentally involved in the regulation of spermatogenesis and testicular steroidogenesis. However, activin A also has a much broader role in control of inflammation, fibrosis and immunity. In the Sertoli cell, activin A is regulated by signalling pathways that normally regulate stress and inflammation, signalling pathways that intersect with the classical hormonal regulatory pathways mediated by FSH. Modulation of activin A production and activity during spermatogenesis is implicated in the fine control of the cycle of the seminiferous epithelium. The immunoregulatory properties of activin A also suggest that it may be involved in maintaining testicular immune privilege. Consequently, elevated activin A production within the testis during inflammation and infection may contribute to spermatogenic failure, fibrosis and testicular damage.
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Affiliation(s)
- Mark P Hedger
- Monash Institute of Medical Research, Monash University, Melbourne, Victoria, Australia.
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Abstract
Inhibin A and B, dimeric glycoproteins comprising an α- and β((A/B))-subunit, negatively regulate follicle stimulating hormone (FSH) synthesis by the pituitary. The expression of α- and β-subunits within Sertoli cells of the testis and granulosa cells of the ovary is controlled by a range of transcription factors, including CREB, SP-1, Smads, and GATA factors. The inhibin α- and β-subunits are synthesized as precursor molecules consisting of an N-terminal propeptide and a C-terminal mature domain. Recently, we showed that hydrophobic residues within the propeptides of the α- and β-subunits interact noncovalently with their mature domains, maintaining the molecules in a conformation competent for dimerization. Dimeric precursors are cleaved by proprotein convertases and mature inhibins are secreted from the cell noncovalently associated with their propeptides. Propeptides may increase the half-life of inhibin A and B in circulation, but they are readily displaced in the presence of the high-affinity receptors, betaglycan, and ActRII.
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Weng Q, Medan MS, Xu M, Tsubota T, Watanabe G, Taya K. Seasonal changes in immunolocalization of inhibin/activin subunits and testicular activity in wild male raccoon dogs (Nyctereutes procyonoides). J Reprod Dev 2006; 52:503-10. [PMID: 16702758 DOI: 10.1262/jrd.18011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Thirty-four pairs of testes from wild adult raccoon dogs (Nyctereutes procyonoides) were obtained between September 2000 and May 2003. The cellular localization of the inhibin alpha and inhibin/activin (betaA and betaB) subunits in wild raccoon dog testes was investigated. The testicular weight and size and seminiferous tubule diameters were measured. There were marked seasonal variations in testicular weight and size and seminiferous tubule diameters, with values relatively low in September and high in March. Spermatogonia and primary spermatocytes were observed in September, and spermatogonia, spermatocytes, and round spermatids were present in January. All types of spermatogenic cells, including mature spermatozoa, were found in March, indicating that the breeding season is around March in Japan. Thereafter, spermatogonia and degenerating spermatocytes were observed in April. The sections of testes were immunostained by the avidin-biotin-peroxidase complex method (ABC) using polyclonal antisera raised against porcine inhibin alpha, inhibin/activin betaA and inhibin/activin betaB. The inhibin alpha and inhibin/activin (betaA and betaB) subunits were only expressed in Leydig cells in September. On the other hand, the inhibin alpha, betaA, and betaB subunits were observed in Leydig cells and Sertoli cells, but not in germ cells, in March. These results suggest that the testes of wild raccoon dogs have the ability to synthesize inhibins, and the cellular localization of inhibin/activin subunits showed season-related changes in the breeding and non-breeding seasons.
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Affiliation(s)
- Qiang Weng
- Faculty of Biological Science and Technology, Beijing Forestry University, China
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Ahtiainen M, Toppari J, Poutanen M, Huhtaniemi I. Indirect Sertoli cell-mediated ablation of germ cells in mice expressing the inhibin-alpha promoter/herpes simplex virus thymidine kinase transgene. Biol Reprod 2004; 71:1545-50. [PMID: 15240419 DOI: 10.1095/biolreprod.104.028183] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
In the present study, we describe a novel mouse model for inducible germ cell ablation. The mice express herpes simplex virus thymidine kinase (HSV-TK) under the inhibin-alpha subunit promoter (Inhalpha). When adult transgenic (TG) mice were treated with famciclovir (FCV) for 4 wk, their spermatogenesis was totally abolished, with only Sertoli cells and few spermatids remaining in the seminiferous tubules. However, testicular steroidogenesis was not affected. Shorter treatment periods allowed us to follow up the progression of germ cell death: After 3 days, spermatogonia and preleptotene spermatocytes were no longer present. After a 1-wk treatment, spermatogonia, preleptotene, and zygotene spermatocytes were missing and the amount of pachytene spermatocytes was decreased. After a 2-wk treatment, round and elongating spermatids were present. During the third week, round spermatids were lost and, finally, after a 4-wk treatment, only Sertoli cells and few spermatids were present. Interestingly, the transgene is detected in Leydig and Sertoli cells but not in spermatogonia. This suggests that FCV is phosphorylated in Sertoli cells, and thereafter, leaks to neighboring spermatogonia, apparently through cell-cell junctions present, enabling trafficking of phosphorylated FCV. Because of the many mitotic divisions they pass through, the spermatogonia are very sensitive to toxins interfering with DNA replication, while nondividing Sertoli cells are protected. Using transillumination-assisted microdissection of the seminiferous tubules, the gene-expression patterns analyzed corresponded closely to the histologically observed progression of cell death. Thus, the model offers a new tool for studies on germ cell-Sertoli cell interactions by accurate alteration of the germ cell composition in seminiferous tubules.
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Affiliation(s)
- Maarit Ahtiainen
- Department of Physiology, University of Turku, FIN-20520 Turku, Finland
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Andersson AM, Müller J, Skakkebaek NE. Different roles of prepubertal and postpubertal germ cells and Sertoli cells in the regulation of serum inhibin B levels. J Clin Endocrinol Metab 1998; 83:4451-8. [PMID: 9851793 DOI: 10.1210/jcem.83.12.5360] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To elucidate the role of germ cells in the regulation of inhibin B secretion, serum inhibin B levels in prepubertal boys and adult men whom had a concurrent testicular biopsy showing either normal or impaired testicular function were compared. In addition, by immunohistochemistry the cellular localization of the two subunits of inhibin B (alpha and betaB) were examined in adult testicular tissue with normal spermatogenesis, spermatogenic arrest, or Sertoli cell only tubules (SCO) as well as in normal testicular tissue from an infant and a prepubertal boy. Adult men with testicular biopsy showing normal spermatogenesis (n=8) or spermatogenic arrest (n=5) had median inhibin B levels of 148 pg/mL (range, 37-463 pg/mL) and 68 pg/mL (range, 29-186 pg/mL), respectively, corresponding to normal or near-normal levels of our reference population (165 and 31-443 pg/mL; n=358). Men with SCO (n=9) had undetectable or barely detectable (n=1) serum levels of inhibin B. In contrast to adults, prepubertal boys with SCO (n=12) all had measurable serum inhibin B levels that corresponded to our previously determined normal range in healthy prepubertal boys (n=114). However, in postpubertal samples from the same SCO boys, inhibin B levels were undetectable as in the adult SCO men. Intense inhibin alpha-subunit immunostaining was evident in Sertoli cells in both prepubertal and adult testes. In the prepubertal testis, positive immunostaining for the betaB-subunit was observed in Sertoli cells. In the adult testis, intense immunostaining for the betaB-subunit was evident in germ cells from the pachytene spermatocyte to early spermatid stages and to a lesser degree in Leydig cells, but not in Sertoli cells or other stages of germ cells. Thus, surprisingly, in adult men the two subunits constituting inhibin B were expressed by different cell types. We speculate that during puberty Sertoli cell maturation induces a change in inhibin subunit expression. Thus, immature Sertoli cells express both alpha and betaB inhibin subunits, whereas fully differentiated Sertoli cells only express the alpha-subunit. The correlation in adult men between serum inhibin B levels and spermatogenesis may be due to the fact that inhibin B in adult men is possibly a joint product of Sertoli cells and germ cells, including the stages from pachytene spermatocytes to early spermatids.
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Affiliation(s)
- A M Andersson
- Department of Growth and Reproduction, University of Copenhagen, Denmark
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Di Simone N, Hall HA, Welt C, Schneyer AL. Activin regulates betaA-subunit and activin receptor messenger ribonucleic acid and cellular proliferation in activin-responsive testicular tumor cells. Endocrinology 1998; 139:1147-55. [PMID: 9492049 DOI: 10.1210/endo.139.3.5800] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Activin, a member of the transforming growth factor-beta superfamily of growth and differentiation factors, has a number of actions in embryonic as well as adult tissues. These actions are mediated via a family of receptors containing two subtypes and at least two members of each subtype. Recent evidence demonstrates that activin-responsive cell lines containing different subsets of these receptors are valuable models for dissecting functional relationships among receptor subtype, signal transduced, and response obtained. TT cells, derived from a p53(-/-)/alpha-inhibin(-/-) mouse testicular tumor, respond to activin by proliferating, a response that can be inhibited by follistatin (FS) treatment. Using semiquantitative RT-PCR methods, we characterized steady state messenger RNA (mRNA) levels for the inhibin/activin subunits, FS, and activin receptor subtypes under basal conditions and in the presence of activin or FS. These cells produced ample immunoreactive activin A and FS, necessitating higher treatment doses to observe any modulation of cellular proliferation. Furthermore, in the presence of exogenous activin, mRNA levels for activin receptor type IIA (ACTRIIA) and betaA were significantly and profoundly suppressed. In addition, both ACTR1B and ACTRIIB were detectable and down-regulated by exogenous activin, although not to the degree observed for ACTRIIA and betaA. Finally, activin treatment at the higher doses, which decreased activin receptor mRNA levels, resulted in inhibition of cellular proliferation. Taken together with previous observations, our results support the model that these tumor cells respond to an autocrine activin signal by proliferating, whereas exogenous or excess activin results in down-regulation of activin receptor and activin biosynthesis, suggesting a potential autocrine/paracrine mechanism by which activin can modulate its own signal.
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Affiliation(s)
- N Di Simone
- Reproductive Endocrine Unit and National Center for Infertility Research, Massachusetts General Hospital, Boston 02114, USA
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Plant TM, Padmanabhan V, Ramaswamy S, McConnell DS, Winters SJ, Groome N, Midgley AR, McNeilly AS. Circulating concentrations of dimeric inhibin A and B in the male rhesus monkey (Macaca mulatta). J Clin Endocrinol Metab 1997; 82:2617-21. [PMID: 9253343 DOI: 10.1210/jcem.82.8.4164] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The purpose of this study was to determine the relative concentrations of inhibin A and B in peripheral serum of the adult male rhesus monkey and to examine the testicular contribution to these circulating forms of inhibin. In addition, inhibin B concentrations were also determined in peripheral sera of neonatal and juvenile males and in spermatic vein blood of adults. Immunoradiometric assays specific for the measurement of inhibin A and B were used. These assays also provided an opportunity to reexamine the physiological significance of a replacement infusion of recombinant human (rh)-inhibin A previously employed to study the role of this hormone in regulating FSH secretion in the monkey. In intact adults, the mean (+/-SE) serum concentration of inhibin B was 1008 +/- 184 pg/mL. In contrast, circulating inhibin A concentrations were very low (< 46 pg/mL). Inhibin B was consistently detected in neonatal monkey serum (275 +/- 57 pg/mL), and concentrations of this inhibin dimer increased throughout postnatal development, reaching maximum values in adulthood. Circulating inhibin A concentrations in neonatal and juvenile monkeys were undetectable (< 7 pg/mL). Both forms of inhibin were generally undetectable in castrate sera. The ratio of inhibin B concentrations in testicular venous blood to those in the peripheral circulation was 1.4:1. These findings indicate that, in the male monkey, inhibin B is the principal form of circulating dimeric inhibin, and that this hormone is derived exclusively from the testis. The elevated levels of circulating inhibin B in the juvenile male monkey suggest that, during this phase of development, testicular inhibin B secretion is relatively gonadotropin independent. Additionally, we found that the concentration of circulating inhibin A in castrate animals that had earlier received an iv infusion of rh-inhibin A (832 ng/h/kg BW) was 9881 +/- 2135 pg/mL, indicating that this mode of inhibin replacement may not have been entirely physiological.
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Affiliation(s)
- T M Plant
- Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine, Pennsylvania 15261, USA
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Wallace EM, Healy DL. Inhibins and activins: roles in clinical practice. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1996; 103:945-56. [PMID: 8863689 DOI: 10.1111/j.1471-0528.1996.tb09541.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- E M Wallace
- Department of Obstetrics and Gynaecology, University of Edinburgh, Scotland
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Herrera J, Garcia-Castro JR, Rodriguez-Maldonado E, Mendieta E, Bermúdez JA. Sertoli cell conditioned media modulate the androgen biosynthetic pathways in rat Leydig cell primary cultures. ARCHIVES OF ANDROLOGY 1996; 37:127-33. [PMID: 8886262 DOI: 10.3109/01485019608988513] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Increasing evidence suggests the presence of local modulators that contribute to testicular function regulation in rats. The seminiferous tubules and Sertoli cell factors influence the steroidogenic activity of Leydig cells. Addition of Sertoli cell conditioned media to primary cultures of adult rat Leydig cells produces in a dose-dependent manner an inhibition of testosterone production with a concomitant decrease in the C21 delta 4-intermediates of the steroidogenic pathway, modifying the C21/C19 ratios in normal cells. The nature and mechanisms of action of this putative modulating activity are currently under study.
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Affiliation(s)
- J Herrera
- Laboratorio de Andrología, Hospital Luis Castelazo Ayala, Instituto Mexicano del Seguro Social, México
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Kharbanda K, Ramakrishnan PR, Duraiswami S. Rat prostatic inhibin: less than 35 kDa protein(s). Prostate 1995; 27:84-9. [PMID: 7638086 DOI: 10.1002/pros.2990270204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
An attempt was made to purify and physicochemically characterize the inhibin-like activity of rat ventral prostate based on the technique of immunosorption. It was possible to partially purify prostatic inhibin by affinity chromatography and the molecular size of inhibin-like material was shown to be less than 35 kDa.
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Affiliation(s)
- K Kharbanda
- Department of Zoology, University of Delhi, India
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Moore A, Krummen LA, Mather JP. Inhibins, activins, their binding proteins and receptors: interactions underlying paracrine activity in the testis. Mol Cell Endocrinol 1994; 100:81-6. [PMID: 8056163 DOI: 10.1016/0303-7207(94)90283-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The inhibin-related peptides are present in the testis from early gestation through adulthood. They are produced from multiple testicular sites in a highly regulated manner, suggesting important paracrine roles. Similarly, receptors for these peptides are located in specific stages of the seminiferous tubule and on particular cell types, and an additional level of control is afforded by specific binding proteins, such as follistatin, which may regulate bioavailability. The actions of these factors include the modulation of interstitial cell function and the increase of spermatogonial proliferation in vitro. It thus appears that activin and inhibin are significant factors in the local control of testicular function.
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Affiliation(s)
- A Moore
- Genentech Inc., South San Francisco, CA 94080
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Robertson DM, Risbridger GP, de Kretser DM. The physiology of testicular inhibin and related proteins. BAILLIERE'S CLINICAL ENDOCRINOLOGY AND METABOLISM 1992; 6:355-72. [PMID: 1616449 DOI: 10.1016/s0950-351x(05)80154-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The roles of inhibin and related proteins in the male remain unclear, although it is becoming increasingly evident that they play a part in FSH regulation and testicular function, including spermatogenesis. The difficulties associated with these questions have been the limited availability of inhibin and related proteins for in vivo studies, the absence of specific assay methods, and the unclear relationship of inhibin and testosterone in the regulation of FSH secretion. With the availability of human recombinant preparations and the current development of new assays, it is anticipated that many of these questions will be resolved.
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Grootenhuis AJ, van Beurden WM, Timmerman MA, de Jong FH. Follicle-stimulating hormone-stimulated secretion of an immunoreactive 29 kDa inhibin alpha-subunit complex, but not of 32 kDa bioactive inhibin, from cultured immature rat Sertoli cells. Mol Cell Endocrinol 1990; 74:125-32. [PMID: 2128627 DOI: 10.1016/0303-7207(90)90114-n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The medium of cultured Sertoli cells from immature rat testes contains 29 and 32 kDa proteins, which are recognized by an antiserum against the 22 N-terminal amino acids of the inhibin alpha-subunit. These proteins were detected by immunoprecipitation of labelled proteins after incubation of Sertoli cells with [35S]methionine, and by Western blotting. The amount of the 32 kDa protein was not affected by the addition of follicle-stimulating hormone (FSH) to the culture medium of the Sertoli cells, whereas FSH induced a large increase of the amount of the 29 kDa protein. Finally, the 29 and 32 kDa proteins in the medium from control and FSH-stimulated Sertoli cells were separated by sodium dodecyl sulfate-polyacrylamide electrophoresis, and inhibin bio- and immunoactivity were determined in eluates of the slices of the gel. Equal amounts of bioactivity were found in control and FSH-stimulated samples at 32 kDa, while the amount of immunoactivity at 29 kDa was increased; no bioactivity was detected in the eluates of these slices. It is concluded that FSH stimulates the secretion of a 29 kDa inhibin-like protein, which does not contain inhibin bioactivity. This indicates that results of experiments, in which antibodies against N-terminal peptides of the inhibin alpha-subunit are used to detect inhibin, do not necessarily reflect the amount of bioactive inhibin produced.
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Affiliation(s)
- A J Grootenhuis
- Department of Biochemistry (Division of Chemical Endocrinology), Erasmus University Rotterdam, The Netherlands
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Grootenhuis AJ, Melsert R, Timmerman MA, Hoogerbrugge JW, Rommerts FF, de Jong FH. Short-term stimulatory effect of Sertoli cell conditioned medium on Leydig cell steroidogenesis is not mediated by inhibin. JOURNAL OF STEROID BIOCHEMISTRY 1990; 36:445-9. [PMID: 2120516 DOI: 10.1016/0022-4731(90)90086-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Addition of concentrated rat Sertoli cell conditioned medium (rSCCM) to isolated Leydig cells from immature rats stimulated steroid production more than 13-fold within 4 h. LH-stimulated steroidogenesis was not enhanced by addition of rSCCM. The biological activity of the concentrated rSCCM was higher after incubation of Sertoli cells with FSH, whereas FSH alone did not stimulate steroid production. This effect of rSCCM was not due to inhibin, since highly purified 32 kDa rat inhibin, in doses equivalent to those present in rSCCM, had no effect on steroidogenesis during the 4 h incubation period. Furthermore, inhibin could be separated from the Leydig cell stimulating factor by anion-exchange chromatography. These results indicate a short-term paracrine control of Leydig cell steroidogenesis by Sertoli cell derived factors, which differ from inhibin.
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Affiliation(s)
- A J Grootenhuis
- Department of Biochemistry, Erasmus University Rotterdam, The Netherlands
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