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de Villiers C, Maree L, Katz AA, van der Horst G. The in-vitro effect of gonadotropin-releasing hormones, GnRH-I and GnRH-II, on the motility, vitality and acrosome integrity of Vervet monkey (Chlorocebus aethiops) spermatozoa. Reprod Domest Anim 2022; 57:1394-1405. [PMID: 35877200 DOI: 10.1111/rda.14216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 07/14/2022] [Accepted: 07/23/2022] [Indexed: 11/29/2022]
Abstract
Two isoforms of the gonadotropin-releasing hormone (GnRH), GnRH-I and GnRH-II, are expressed in mammals, and the presence of one or more GnRH-like peptides has been demonstrated in the male reproductive tract. GnRH and its receptors (GnRHR) are present in human and non-human primate testis, prostate, epididymis, seminal vesicle, spermatozoa and seminal human plasma. GnRH-II is site-specific and acts directly in an inhibitory or stimulatory fashion. Previous studies speculated that GnRH-II could disrupt specific sperm processes, such as sperm motility or capacitation and could be utilized as an effective contraceptive agent. Our study aimed to investigate the in-vitro effects of GnRH-I and GnRH-II on Vervet monkey sperm function. Electro-ejaculated semen samples from 10 Vervet monkeys (Chlorocebus aethiops) were used to select motile sperm populations. Sperm aliquots were incubated with GnRH-I and GnRH-II at different concentrations for 1 h, where after sperm motility and kinematic parameters were assessed using the automated Sperm Class Analyser. Additional sperm aliquots were incubated with two 10-amino acid control peptides, a non-related peptide and an inactive peptide to exclude the possible influence on sperm motility from other peptides with a structure similar to GnRH. Additionally, a GnRHR-I antagonist (GnRHR-A), Cetrorelix, was tested to establish its antagonistic capability on GnRH. The effect of selected concentrations of GnRH-I and GnRH-II on sperm vitality and acrosome intactness was also evaluated after 10- and 60 min exposure. Analysis of the percentage total sperm motility revealed that different concentrations for GnRH-I and GnRH-II inhibited sperm motility significantly. While sperm progressiveness was also notably affected and a trend of decreased sperm kinematics were evident, no effect was found on sperm vitality or acrosome intactness. The non-related and inactive peptides had no impact on sperm motility. The GnRHR-A demonstrated no effect on sperm motility and effectively blocked the inhibitory outcome on the motility of both GnRH isoforms. While GnRH-I or GnRH-II at low-dose concentrations resulted in in-vitro inhibition of sperm motility, it appears to have no adverse effects on other sperm functional parameters evaluated. These collective observations possibly indicate an essential role for GnRH in the in-vivo process of sperm selection in the female reproductive tract.
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Affiliation(s)
- Charon de Villiers
- PUDAC-Delft Animal Facility, South African Medical Research Council, Cape Town, South Africa
| | - Liana Maree
- Department of Medical Biosciences, University of the Western Cape, Bellville, South Africa
| | - Arieh A Katz
- Department of Integrative Biomedical Sciences and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Gerhard van der Horst
- Department of Medical Biosciences, University of the Western Cape, Bellville, South Africa
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Sharma A, Thaventhiran T, Minhas S, Dhillo WS, Jayasena CN. Kisspeptin and Testicular Function-Is it Necessary? Int J Mol Sci 2020; 21:ijms21082958. [PMID: 32331420 PMCID: PMC7216047 DOI: 10.3390/ijms21082958] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/17/2020] [Accepted: 04/21/2020] [Indexed: 01/05/2023] Open
Abstract
The role of kisspeptin in stimulating hypothalamic GnRH is undisputed. However, the role of kisspeptin signaling in testicular function is less clear. The testes are essential for male reproduction through their functions of spermatogenesis and steroidogenesis. Our review focused on the current literature investigating the distribution, regulation and effects of kisspeptin and its receptor (KISS1/KISS1R) within the testes of species studied to date. There is substantial evidence of localised KISS1/KISS1R expression and peptide distribution in the testes. However, variability is observed in the testicular cell types expressing KISS1/KISS1R. Evidence is presented for modulation of steroidogenesis and sperm function by kisspeptin signaling. However, the physiological importance of such effects, and whether these are paracrine or endocrine manifestations, remain unclear.
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Affiliation(s)
- Aditi Sharma
- Section of Investigative Medicine, Imperial College, 6th Floor, Commonwealth Building, Hammersmith Hospital, 150 Du Cane Road, London W12 0NN, UK; (A.S.); (T.T.); (W.S.D.)
| | - Thilipan Thaventhiran
- Section of Investigative Medicine, Imperial College, 6th Floor, Commonwealth Building, Hammersmith Hospital, 150 Du Cane Road, London W12 0NN, UK; (A.S.); (T.T.); (W.S.D.)
| | - Suks Minhas
- Department of Urology, Imperial College Healthcare NHS Trust, Charing Cross Hospital, Fulham Palace Road, Hammersmith, London W6 8RF, UK;
| | - Waljit S. Dhillo
- Section of Investigative Medicine, Imperial College, 6th Floor, Commonwealth Building, Hammersmith Hospital, 150 Du Cane Road, London W12 0NN, UK; (A.S.); (T.T.); (W.S.D.)
| | - Channa N. Jayasena
- Section of Investigative Medicine, Imperial College, 6th Floor, Commonwealth Building, Hammersmith Hospital, 150 Du Cane Road, London W12 0NN, UK; (A.S.); (T.T.); (W.S.D.)
- Correspondence:
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Atwood CS, Vadakkadath Meethal S. The spatiotemporal hormonal orchestration of human folliculogenesis, early embryogenesis and blastocyst implantation. Mol Cell Endocrinol 2016; 430:33-48. [PMID: 27045358 DOI: 10.1016/j.mce.2016.03.039] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 03/30/2016] [Indexed: 11/18/2022]
Abstract
The early reproductive events starting with folliculogenesis and ending with blastocyst implantation into the uterine endometrium are regulated by a complex interplay among endocrine, paracrine and autocrine factors. This review examines the spatiotemporal integration of these maternal and embryonic signals that are required for successful reproduction. In coordination with hypothalamic-pituitary-gonadal (HPG) hormones, an intraovarian HPG-like axis regulates folliculogenesis, follicular quiescence, ovulation, follicular atresia, and corpus luteal functions. Upon conception and passage of the zygote through the fallopian tube, the contribution of maternal hormones in the form of paracrine secretions from the endosalpinx to embryonic development declines, with autocrine and paracrine signaling becoming increasingly important as instructional signals for the differentiation of the early zygote/morula into a blastocyst. These maternal and embryonic signals include activin and gonadotropin-releasing hormone 1 (GnRH1) that are crucial for the synthesis and secretion of the 'pregnancy' hormone human chorionic gonadotropin (hCG). hCG in turn signals pre-implantation embryonic cell division and sex steroid production required for stem cell differentiation, and subsequent blastulation, gastrulation, cavitation and blastocyst formation. Upon reaching the uterus, blastocyst hatching occurs under the influence of decreased activin signaling, while the attachment and invasion of the trophoblast into the endometrium appears to be driven by a decrease in activin signaling, and by increased GnRH1 and hCG signaling that allows for tissue remodeling and the controlled invasion of the blastocyst into the uterine endometrium. This review demonstrates the importance of integrative endocrine, paracrine, and autocrine signaling for successful human reproduction.
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Affiliation(s)
- Craig S Atwood
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53705, USA; Geriatric Research, Education and Clinical Center, Veterans Administration Hospital, Madison, WI 53705, USA; School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Joondalup, 6027 WA, Australia.
| | - Sivan Vadakkadath Meethal
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53705, USA; Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, WI 53792, USA
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Chianese R, Ciaramella V, Fasano S, Pierantoni R, Meccariello R. Kisspeptin drives germ cell progression in the anuran amphibian Pelophylax esculentus: a study carried out in ex vivo testes. Gen Comp Endocrinol 2015; 211:81-91. [PMID: 25452028 DOI: 10.1016/j.ygcen.2014.11.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 11/03/2014] [Accepted: 11/08/2014] [Indexed: 12/31/2022]
Abstract
Kisspeptin, via Gpr54 receptor, regulates puberty onset in most vertebrates. Thus, the direct involvement of kisspeptin activity in testis physiology was investigated in the anuran amphibian, Pelophylax esculentus. In this vertebrate gpr54 mRNA has been localized in both interstitial compartment and spermatogonia (SPG), whereas SPG proliferation requires the cooperation between estradiol and testicular Gonadotropin releasing hormone (Gnrh). In the pre-reproductive period, dose response curve to assess the effects of Kisspeptin-10 (Kp-10) was carried out in vitro (dose range: 10(-9)-10(-6)M; incubation times: 1 and 4h); proliferative activity and germ cell progression were evaluated by expression analysis of proliferating cell nuclear antigen (pcna), estrogen receptor beta (erβ), Gnrh system (gnrh1, gnrh2, gnrhr1, r2, r3) and by the count of empty, mitotic and meiotic tubules. All selected markers were up regulated at 4h Kp-10 incubation. Histological analysis also proved the increase of mitotic activity and the progression of spermatogenesis. Besides Kp-10 modulation of testicular Gnrh system, in vitro treatment with 17β-estradiol (10(-6)M) ± the antagonist ICI182-780 (10(-5)M) revealed gnrh2 and gnrhr3 estrogen dependent expression. In the reproductive period, testes were incubated for 1 and 4h with Kp-10 (10(-7)M) or Kp-10 (10(-7)M)+kisspeptin antagonist [Kp-234 (10(-6)M)]. Results obtained in the pre-reproductive period were confirmed and Kp-234 completely counteracted Kp-10 effects. In conclusion, Kp-10 modulated the expression of pcna, erβ, gnrhs and gnrhrs, inducing the progression of the spermatogenesis.
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Affiliation(s)
- Rosanna Chianese
- Dipartimento di Medicina Sperimentale Sezione "F. Bottazzi", Seconda Università di Napoli, Via Costantinopoli 16, 80138 Napoli, Italy.
| | - Vincenza Ciaramella
- Dipartimento di Medicina Sperimentale Sezione "F. Bottazzi", Seconda Università di Napoli, Via Costantinopoli 16, 80138 Napoli, Italy.
| | - Silvia Fasano
- Dipartimento di Medicina Sperimentale Sezione "F. Bottazzi", Seconda Università di Napoli, Via Costantinopoli 16, 80138 Napoli, Italy.
| | - Riccardo Pierantoni
- Dipartimento di Medicina Sperimentale Sezione "F. Bottazzi", Seconda Università di Napoli, Via Costantinopoli 16, 80138 Napoli, Italy.
| | - Rosaria Meccariello
- Dipartimento di Scienze Motorie e del Benessere, Università di Napoli Parthenope, Via Medina 40, 80133 Napoli, Italy.
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Ciaramella V, Chianese R, Pariante P, Fasano S, Pierantoni R, Meccariello R. Expression analysis of gnrh1 and gnrhr1 in spermatogenic cells of rat. Int J Endocrinol 2015; 2015:982726. [PMID: 25861269 PMCID: PMC4377535 DOI: 10.1155/2015/982726] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Accepted: 03/02/2015] [Indexed: 01/31/2023] Open
Abstract
Hypothalamic Gonadotropin Releasing Hormone (GnRH), via GnRH receptor (GnRHR), is the main actor in the control of reproduction, in that it induces the biosynthesis and the release of pituitary gonadotropins, which in turn promote steroidogenesis and gametogenesis in both sexes. Extrabrain functions of GnRH have been extensively described in the past decades and, in males, local GnRH activity promotes the progression of spermatogenesis and sperm functions at several levels. The canonical localization of Gnrh1 and Gnrhr1 mRNA is Sertoli and Leydig cells, respectively, but ligand and receptor are also expressed in germ cells. Here, we analysed the expression rate of Gnrh1 and Gnrhr1 in rat testis (180 days old) by quantitative real-time PCR (qPCR) and by in situ hybridization we localized Gnrh1 and Gnrhr1 mRNA in different spermatogenic cells of adult animals. Our data confirm the testicular expression of Gnrh1 and of Gnrhr1 in somatic cells and provide evidence that their expression in the germinal compartment is restricted to haploid cells. In addition, not only Sertoli cells connected to spermatids in the last steps of maturation but also Leydig and peritubular myoid cells express Gnrh1.
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Affiliation(s)
- Vincenza Ciaramella
- Dipartimento di Medicina Sperimentale Sezione “F. Bottazzi”, Seconda Università di Napoli, Via Costantinopoli 16, 80138 Napoli, Italy
| | - Rosanna Chianese
- Dipartimento di Medicina Sperimentale Sezione “F. Bottazzi”, Seconda Università di Napoli, Via Costantinopoli 16, 80138 Napoli, Italy
| | - Paolo Pariante
- Dipartimento di Medicina Sperimentale Sezione “F. Bottazzi”, Seconda Università di Napoli, Via Costantinopoli 16, 80138 Napoli, Italy
| | - Silvia Fasano
- Dipartimento di Medicina Sperimentale Sezione “F. Bottazzi”, Seconda Università di Napoli, Via Costantinopoli 16, 80138 Napoli, Italy
| | - Riccardo Pierantoni
- Dipartimento di Medicina Sperimentale Sezione “F. Bottazzi”, Seconda Università di Napoli, Via Costantinopoli 16, 80138 Napoli, Italy
| | - Rosaria Meccariello
- Dipartimento di Scienze Motorie e del Benessere, Università di Napoli Parthenope, Via Medina 40, 80133 Napoli, Italy
- *Rosaria Meccariello:
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Meccariello R, Chianese R, Chioccarelli T, Ciaramella V, Fasano S, Pierantoni R, Cobellis G. Intra-testicular signals regulate germ cell progression and production of qualitatively mature spermatozoa in vertebrates. Front Endocrinol (Lausanne) 2014; 5:69. [PMID: 24847312 PMCID: PMC4021137 DOI: 10.3389/fendo.2014.00069] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 04/22/2014] [Indexed: 11/13/2022] Open
Abstract
Spermatogenesis, a highly conserved process in vertebrates, is mainly under the hypothalamic-pituitary control, being regulated by the secretion of pituitary gonadotropins, follicle stimulating hormone, and luteinizing hormone, in response to stimulation exerted by gonadotropin releasing hormone from hypothalamic neurons. At testicular level, gonadotropins bind specific receptors located on the somatic cells regulating the production of steroids and factors necessary to ensure a correct spermatogenesis. Indeed, besides the endocrine route, a complex network of cell-to-cell communications regulates germ cell progression, and a combination of endocrine and intra-gonadal signals sustains the production of high quality mature spermatozoa. In this review, we focus on the recent advances in the area of the intra-gonadal signals supporting sperm development.
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Affiliation(s)
- Rosaria Meccariello
- Dipartimento di Scienze Motorie e del Benessere, Università di Napoli Parthenope, Naples, Italy
| | - Rosanna Chianese
- Dipartimento di Medicina Sperimentale sez “F. Bottazzi”, Seconda Università degli Studi di Napoli, Naples, Italy
| | - Teresa Chioccarelli
- Dipartimento di Medicina Sperimentale sez “F. Bottazzi”, Seconda Università degli Studi di Napoli, Naples, Italy
| | - Vincenza Ciaramella
- Dipartimento di Medicina Sperimentale sez “F. Bottazzi”, Seconda Università degli Studi di Napoli, Naples, Italy
| | - Silvia Fasano
- Dipartimento di Medicina Sperimentale sez “F. Bottazzi”, Seconda Università degli Studi di Napoli, Naples, Italy
| | - Riccardo Pierantoni
- Dipartimento di Medicina Sperimentale sez “F. Bottazzi”, Seconda Università degli Studi di Napoli, Naples, Italy
- *Correspondence: Riccardo Pierantoni, Dipartimento di Medicina Sperimentale sez “F. Bottazzi”, Seconda Università degli Studi di Napoli, Via Costantinopoli 16, Naples 80138, Italy e-mail:
| | - Gilda Cobellis
- Dipartimento di Medicina Sperimentale sez “F. Bottazzi”, Seconda Università degli Studi di Napoli, Naples, Italy
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Meccariello R, Battista N, Bradshaw HB, Wang H. Updates in reproduction coming from the endocannabinoid system. Int J Endocrinol 2014; 2014:412354. [PMID: 24550985 PMCID: PMC3914453 DOI: 10.1155/2014/412354] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 11/20/2013] [Accepted: 12/04/2013] [Indexed: 12/26/2022] Open
Abstract
The endocannabinoid system (ECS) is an evolutionarily conserved master system deeply involved in the central and local control of reproductive functions in both sexes. The tone of these lipid mediators-deeply modulated by the activity of biosynthetic and hydrolyzing machineries-regulates reproductive functions from gonadotropin discharge and steroid biosynthesis to the formation of high quality gametes and successful pregnancy. This review provides an overview on ECS and reproduction and focuses on the insights in the regulation of endocannabinoid production by steroids, in the regulation of male reproductive activity, and in placentation and parturition. Taken all together, evidences emerge that the activity of the ECS is crucial for procreation and may represent a target for the therapeutic exploitation of infertility.
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Affiliation(s)
- Rosaria Meccariello
- Dipartimento di Scienze Motorie e del Benessere, Università di Napoli Parthenope, via Medina 40, 80133 Napoli, Italy
- *Rosaria Meccariello:
| | - Natalia Battista
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64100 Teramo, Italy
- European Center for Brain Research (CERC), Santa Lucia Foundation, 00143 Rome, Italy
| | - Heather B. Bradshaw
- Department of Psychological and Brain Sciences, The Kinsey Institute for Research in Sex, Gender, and Reproduction, Indiana University, Bloomington, IN 47405, USA
| | - Haibin Wang
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
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Chianese R, Ciaramella V, Scarpa D, Fasano S, Pierantoni R, Meccariello R. Anandamide regulates the expression of GnRH1, GnRH2, and GnRH-Rs in frog testis. Am J Physiol Endocrinol Metab 2012; 303:E475-87. [PMID: 22669247 DOI: 10.1152/ajpendo.00086.2012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Gonadotropin-releasing hormone (either GnRH1 or GnRH2) exerts a local activity in vertebrate testis, including human testis. Relationships between endocannabinoid (eCB) and GnRH systems in gonads have never been elucidated in any species so far. To reveal a cross-talk between eCBs and GnRH at testicular level, we characterized the expression of GnRH (GnRH1 and GnRH2) as well as GnRH receptor (GnRH-R1, -R2, and -R3) mRNA in the testis of the anuran amphibian Rana esculenta during the annual sexual cycle; furthermore, the corresponding transcripts were localized inside the testis by in situ hybridization. The possible endogenous production of the eCB, anandamide (AEA), was investigated in testis by analyzing the expression of its biosynthetic enzyme, Nape-pld. Incubations of testis pieces with AEA were carried out in the postreproductive period (June) and in February, when a new spermatogenetic wave takes place. In June, AEA treatment significantly decreased GnRH1 and GnRH-R2 mRNA, stimulated the transcription of GnRH2 and GnRH-R1, and did not affect GnRH-R3 expression. In February, AEA treatment upregulated GnRH2 and GnRH-R3 mRNA, downregulated GnRH-R2, and did not affect GnRH1 and GnRH-R1 expression. These effects were mediated by type 1 cannabinoid receptor (CB1) since they were fully counteracted by SR141716A (Rimonabant), a selective CB1 antagonist. In conclusion, eCB system modulates GnRH activity in frog testis during the annual sexual cycle in a stage-dependent fashion.
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Affiliation(s)
- Rosanna Chianese
- Dipartimento di Medicina Sperimentale sez F. Bottazzi, Seconda Università di Napoli, via Costantinopoli 16, 80138 Naples, Italy
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Pasten C, Morales P, Kong M. Role of the sperm proteasome during fertilization and gamete interaction in the mouse. Mol Reprod Dev 2005; 71:209-19. [PMID: 15791592 DOI: 10.1002/mrd.20280] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In this work, we have investigated the role of the sperm proteasome during in vitro fertilization (IVF) and gamete interaction in the mouse. Proteasome activity was measured in extract and intact sperm using a specific substrate. In addition, sperm were treated with specific proteasome inhibitors and evaluated during IVF, binding to the zona pellucida, and progesterone- and zona pellucida-induced acrosome reactions. In other experiments, sperm membrane proteins were obtained resuspending them in Triton X-114, shaking vigorously and let standing by 4 hr. Soluble sperm proteins were partitioned in the aqueous phase and sperm membrane proteins in the detergent phase. In both phases, proteasome activity was measured. Labeling of cell surface sperm proteins was carried out with the cell-impermeable NHS-LC biotin, extracted with Triton X-114, and mixing with avidin-agarose beads. Nonpermeabilized sperm were incubated with an anti-proteasome monoclonal antibody and evaluated by indirect immunofluorescence. The results indicate that sperm extracts as well as intact sperm had proteasome activity; the sperm proteasome was involved in IVF, specifically during sperm-zona pellucida binding and the acrosome reaction; soluble sperm membrane proteins exhibited proteasome activity; biotin experiments indicated the presence of proteasomes on the sperm surface, which was corroborated by indirect immunofluorescence experiments. All these observations indicate that the mouse sperm proteasome participates in the binding to the zona pellucida and the acrosome reaction and that there is a pool of proteasomes located on the sperm head.
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Affiliation(s)
- Consuelo Pasten
- Department of Biomedicine, Faculty of Health Sciences, University of Antofagasta, Antofagasta, Chile
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