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Liu Y, Chen SJ, Ai C, Yu PX, Fang M, Wang H. Prenatal dexamethasone exposure impairs rat blood-testis barrier function and sperm quality in adult offspring via GR/KDM1B/FSTL3/TGFβ signaling. Acta Pharmacol Sin 2024; 45:1237-1251. [PMID: 38472317 PMCID: PMC11130295 DOI: 10.1038/s41401-024-01244-5] [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: 10/22/2023] [Accepted: 02/15/2024] [Indexed: 03/14/2024] Open
Abstract
Both epidemiological and animal studies suggest that adverse environment during pregnancy can change the offspring development programming, but it is difficult to achieve prenatal early warning. In this study we investigated the impact of prenatal dexamethasone exposure (PDE) on sperm quality and function of blood-testis barrier (BTB) in adult offspring and the underlying mechanisms. Pregnant rats were injected with dexamethasone (0.1, 0.2 and 0.4 mg·kg-1·d-1, s.c.) from GD9 to GD20. After weaning (PW4), the pups were fed with lab chow. At PW12 and PW28, the male offspring were euthanized to collect blood and testes samples. We showed that PDE significantly decreased sperm quality (including quantity and motility) in male offspring, which was associated with impaired BTB and decreased CX43/E-cadherin expression in the testis. We demonstrated that PDE induced morphological abnormalities of fetal testicle and Sertoli cell development originated from intrauterine. By tracing to fetal testicular Sertoli cells, we found that PDE dose-dependently increased expression of histone lysine demethylases (KDM1B), decreasing histone 3 lysine 9 dimethylation (H3K9me2) levels of follistatin-like-3 (FSTL3) promoter region and increased FSTL3 expression, and inhibited TGFβ signaling and CX43/E-cadherin expression in offspring before and after birth. These results were validated in TM4 Sertoli cells following dexamethasone treatment. Meanwhile, the H3K9me2 levels of FSTL3 promoter in maternal peripheral blood mononuclear cell (PBMC) and placenta were decreased and its expression increased, which was positively correlated with the changes in offspring testis. Based on analysis of human samples, we found that the H3K9me2 levels of FSTL3 promoter in maternal blood PBMC and placenta were positively correlated with fetal blood testosterone levels after prenatal dexamethasone exposure. We conclude that PDE can reduce sperm quality in adult offspring rats, which is related to the damage of testis BTB via epigenetic modification and change of FSTL3 expression in Sertoli cells. The H3K9me2 levels of the FSTL3 promoter and its expression in the maternal blood PBMC can be used as a prenatal warning marker for fetal testicular dysplasia.
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Affiliation(s)
- Yi Liu
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, 430071, China
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan, 430071, China
| | - Si-Jia Chen
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, 430071, China
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan, 430071, China
| | - Can Ai
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, 430071, China
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan, 430071, China
| | - Peng-Xia Yu
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, 430071, China
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan, 430071, China
| | - Man Fang
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, 430071, China
| | - Hui Wang
- Department of Pharmacology, Wuhan University School of Basic Medical Sciences, Wuhan, 430071, China.
- Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan, 430071, China.
- Department of Obstetrics and Gynaecology, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China.
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Tran-Guzman A, Khan A, Culty M. Differential roles of cyclooxygenase enzymes in the regulation of murine juvenile undifferentiated spermatogonia. Andrology 2024; 12:899-917. [PMID: 37772683 DOI: 10.1111/andr.13537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 08/15/2023] [Accepted: 09/10/2023] [Indexed: 09/30/2023]
Abstract
BACKGROUND Acetaminophen and ibuprofen are widely administered to babies due to their presumed safety as over-the-counter drugs. However, no reports exist on the effects of cyclooxygenase inhibitors on undifferentiated spermatogonia and spermatogonial stem cells. Infancy represents a critical period for spermatogonial stem cell formation and disrupting spermatogonial stem cells or their precursors may be associated with infertility and testicular cancer formation. OBJECTIVES The goal of this study was to examine the molecular and functional impact of cyclooxygenase inhibition and silencing on early steps of undifferentiated spermatogonia (u spg) and spermatogonial stem cell development, to assess the potential reproductive risk of pharmaceutical cyclooxygenase inhibitors. METHODS The effects of cyclooxygenase inhibition were assessed using the mouse C18-4 undifferentiated juvenile spermatogonial cell line model, previously shown to include cells with spermatogonial stem cell features, by measuring prostaglandins, cell proliferation, and differentiation, using cyclooxygenase 1- and cyclooxygenase 2-selective inhibitors NS398, celecoxib, and FR122047, acetaminophen, and ibuprofen. Cyclooxygenase 1 gene silencing was achieved using a stable short-hairpin RNA approach and clone selection, then assessing gene and protein expression in RNA sequencing, quantitative real-time polymerase chain reaction, and immunofluorescence studies. RESULTS Cyclooxygenase 2 inhibitors NS398 and celecoxib, as well as acetaminophen, but not ibuprofen, dose-dependently decreased retinoic acid-induced expression of the spg differentiation gene Stra8, while NS398 decreased the spg differentiation marker Kit, suggesting that cyclooxygenase 2 is positively associated with spg differentiation. In contrast, short-hairpin RNA-based cyclooxygenase 1 silencing in C18-4 cells altered cellular morphology and upregulated Stra8 and Kit, implying that cyclooxygenase 1 prevented spg differentiation. Furthermore, RNA sequencing analysis of cyclooxygenase 1 knockdown cells indicated the activation of several signaling pathways including the TGFb, Wnt, and Notch pathways, compared to control C18-4 cells. Notch pathway genes were upregulated by selective cyclooxygenase inhibitors, acetaminophen and ibuprofen. CONCLUSION We report that cyclooxygenase 1 and 2 differentially regulate undifferentiated spermatogonia/spermatogonial stem cell differentiation. Cyclooxygenases regulate Notch3 expression, with the Notch pathway targeted by PGD2. These data suggest an interaction between the eicosanoid and Notch signaling pathways that may be critical for the development of spermatogonial stem cells and subsequent spermatogenesis, cautioning about using cyclooxygenase inhibitors in infants.
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Affiliation(s)
- Amy Tran-Guzman
- Department of Pharmacology and Pharmaceutical Sciences, Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, California, USA
| | - Amina Khan
- Department of Pharmacology and Pharmaceutical Sciences, Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, California, USA
| | - Martine Culty
- Department of Pharmacology and Pharmaceutical Sciences, Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, California, USA
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Inflammation in Urological Malignancies: The Silent Killer. Int J Mol Sci 2023; 24:ijms24010866. [PMID: 36614308 PMCID: PMC9821648 DOI: 10.3390/ijms24010866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 12/02/2022] [Accepted: 12/28/2022] [Indexed: 01/05/2023] Open
Abstract
Several studies have investigated the role of inflammation in promoting tumorigenesis and cancer progression. Neoplastic as well as surrounding stromal and inflammatory cells engage in well-orchestrated reciprocal interactions to establish an inflammatory tumor microenvironment. The tumor-associated inflammatory tissue is highly plastic, capable of continuously modifying its phenotypic and functional characteristics. Accumulating evidence suggests that chronic inflammation plays a critical role in the development of urological cancers. Here, we review the origins of inflammation in urothelial, prostatic, renal, testicular, and penile cancers, focusing on the mechanisms that drive tumor initiation, growth, progression, and metastasis. We also discuss how tumor-associated inflammatory tissue may be a diagnostic marker of clinically significant tumor progression risk and the target for future anti-cancer therapies.
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Whiley PAF, O'Donnell L, Moody SC, Handelsman DJ, Young JC, Richards EA, Almstrup K, Western PS, Loveland KL. Activin A Determines Steroid Levels and Composition in the Fetal Testis. Endocrinology 2020; 161:5818588. [PMID: 32274496 DOI: 10.1210/endocr/bqaa058] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Accepted: 04/08/2020] [Indexed: 12/19/2022]
Abstract
Activin A promotes fetal mouse testis development, including driving Sertoli cell proliferation and cord morphogenesis, but its mechanisms of action are undefined. We performed ribonucleic acid sequencing (RNA-seq) on testicular somatic cells from fetal activin A-deficient mice (Inhba KO) and wildtype littermates at embryonic day (E) E13.5 and E15.5. Analysis of whole gonads provided validation, and cultures with a pathway inhibitor discerned acute from chronic effects of altered activin A bioactivity. Activin A deficiency predominantly affects the Sertoli cell transcriptome. New candidate targets include Minar1, Sel1l3, Vnn1, Sfrp4, Masp1, Nell1, Tthy1 and Prss12. Importantly, the testosterone (T) biosynthetic enzymes present in fetal Sertoli cells, Hsd17b1 and Hsd17b3, were identified as activin-responsive. Activin-deficient testes contained elevated androstenedione (A4), displayed an Inhba gene dose-dependent A4/T ratio, and contained 11-keto androgens. The remarkable accumulation of lipid droplets in both Sertoli and germ cells at E15.5 indicated impaired lipid metabolism in the absence of activin A. This demonstrated for the first time that activin A acts on Sertoli cells to determine local steroid production during fetal testis development. These outcomes reveal how compounds that perturb fetal steroidogenesis can function through cell-specific mechanisms and can indicate how altered activin levels in utero may impact testis development.
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Affiliation(s)
- Penny A F Whiley
- Centre for Reproductive Health, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Liza O'Donnell
- Centre for Reproductive Health, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Sarah C Moody
- Centre for Reproductive Health, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | | | - Julia C Young
- Centre for Reproductive Health, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Anatomy and Developmental Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria, Australia
| | - Elizabeth A Richards
- Centre for Reproductive Health, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Kristian Almstrup
- Department of Growth and Reproduction and International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Copenhagen University Hospital, Copenhagen, Denmark
| | - Patrick S Western
- Centre for Reproductive Health, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Kate L Loveland
- Centre for Reproductive Health, Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Sciences, School of Clinical Sciences, Monash University, Clayton, Victoria, Australia
- Department of Anatomy and Developmental Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria, Australia
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Sun R, Sun YC, Ge W, Tan H, Cheng SF, Yin S, Sun XF, Li L, Dyce P, Li J, Yang X, Shi QH, Shen W. The crucial role of Activin A on the formation of primordial germ cell-like cells from skin-derived stem cells in vitro. Cell Cycle 2016; 14:3016-29. [PMID: 26406115 DOI: 10.1080/15384101.2015.1078031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Primordial germ cells (PGCs) are founder cells of the germ cell lineage, and can be differentiated from stem cells in an induced system in vitro. However, the induction conditions need to be optimized in order to improve the differentiation efficiency. Activin A (ActA) is a member of the TGF-β super family and plays an important role in oogenesis and folliculogenesis. In the present study, we found that ActA promoted PGC-like cells (PGCLCs) formation from mouse skin-derived stem cells (SDSCs) in both embryoid body-like structure (EBLS) differentiation and the co-culture stage in a dose dependent manner. ActA treatment (100 ng/ml) during EBLS differentiation stage and further co-cultured for 6 days without ActA significantly increased PGCLCs from 53.2% to 82.8%, and as well as EBLS differentiation without ActA followed by co-cultured with 100 ng/ml ActA for 4 to 12 days with the percentage of PGCLCs increasing markedly in vitro. Moreover, mice treated with ActA at 100 ng/kg body weight from embryonic day (E) 5.5-12.5 led to more PGCs formation. However, the stimulating effects of ActA were interrupted by Smad3 RNAi, and in an in vitro cultured Smad3(-/-) mouse skin cells scenario. SMAD3 is thus likely a key effecter molecule in the ActA signaling pathway. In addition, we found that the expression of some epiblast cell markers, Fgf5, Dnmt3a, Dnmt3b and Wnt3, was increased in EBLSs cultured for 4 days or PGCLCs co-cultured for 12 days with ActA treatment. Interestingly, at 16 days of differentiation, the percentage of PGCLCs was decreased in the presence of ActA, but the expression of meiosis-relative genes, such as Stra8, Dmc1, Sycp3 and Sycp1, was increased. In conclusion, our data here demonstrated that ActA can promote PGCLC formation from SDSCs in vitro, at early stages of differentiation, and affect meiotic initiation of PGCLCs in later stages.
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Affiliation(s)
- Rui Sun
- a Molecular and Cell Genetics Laboratory; The CAS Key Laboratory of Innate Immunity and Chronic Disease; Hefei National Laboratory for Physical Sciences at Microscale; School of Life Sciences; University of Science and Technology of China ; Hefei , Anhui , China
| | - Yuan-Chao Sun
- b Institute of Reproductive Sciences; Qingdao Agricultural University , Qingdao ; Shandong , China.,c Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University , Qingdao ; Shandong , China
| | - Wei Ge
- b Institute of Reproductive Sciences; Qingdao Agricultural University , Qingdao ; Shandong , China.,c Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University , Qingdao ; Shandong , China
| | - Hui Tan
- b Institute of Reproductive Sciences; Qingdao Agricultural University , Qingdao ; Shandong , China.,c Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University , Qingdao ; Shandong , China
| | - Shun-Feng Cheng
- b Institute of Reproductive Sciences; Qingdao Agricultural University , Qingdao ; Shandong , China.,c Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University , Qingdao ; Shandong , China
| | - Shen Yin
- b Institute of Reproductive Sciences; Qingdao Agricultural University , Qingdao ; Shandong , China.,c Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University , Qingdao ; Shandong , China
| | - Xiao-Feng Sun
- b Institute of Reproductive Sciences; Qingdao Agricultural University , Qingdao ; Shandong , China.,c Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University , Qingdao ; Shandong , China
| | - Lan Li
- b Institute of Reproductive Sciences; Qingdao Agricultural University , Qingdao ; Shandong , China.,c Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University , Qingdao ; Shandong , China
| | - Paul Dyce
- d Department of Animal and Poultry Science ; University of Guelph ; Guelph ; Ontario , Canada
| | - Julang Li
- d Department of Animal and Poultry Science ; University of Guelph ; Guelph ; Ontario , Canada
| | - Xiao Yang
- e Genetic Laboratory of Development and Diseases; Beijing Institute of Biotechnology ; Beijing , China
| | - Qing-Hua Shi
- a Molecular and Cell Genetics Laboratory; The CAS Key Laboratory of Innate Immunity and Chronic Disease; Hefei National Laboratory for Physical Sciences at Microscale; School of Life Sciences; University of Science and Technology of China ; Hefei , Anhui , China.,f Collaborative Innovation Center of Genetics and Development; Fudan University ; Shanghai , China
| | - Wei Shen
- b Institute of Reproductive Sciences; Qingdao Agricultural University , Qingdao ; Shandong , China.,c Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong; College of Animal Science and Technology; Qingdao Agricultural University , Qingdao ; Shandong , China
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Genetic Variants in the Bone Morphogenic Protein Gene Family Modify the Association between Residential Exposure to Traffic and Peripheral Arterial Disease. PLoS One 2016; 11:e0152670. [PMID: 27082954 PMCID: PMC4833382 DOI: 10.1371/journal.pone.0152670] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 03/17/2016] [Indexed: 02/06/2023] Open
Abstract
There is a growing literature indicating that genetic variants modify many of the associations between environmental exposures and clinical outcomes, potentially by increasing susceptibility to these exposures. However, genome-scale investigations of these interactions have been rarely performed particularly in the case of air pollution exposures. We performed race-stratified genome-wide gene-environment interaction association studies on European-American (EA, N = 1623) and African-American (AA, N = 554) cohorts to investigate the joint influence of common single nucleotide polymorphisms (SNPs) and residential exposure to traffic (“traffic exposure”)—a recognized vascular disease risk factor—on peripheral arterial disease (PAD). Traffic exposure was estimated via the distance from the primary residence to the nearest major roadway, defined as the nearest limited access highways or major arterial. The rs755249-traffic exposure interaction was associated with PAD at a genome-wide significant level (P = 2.29x10-8) in European-Americans. Rs755249 is located in the 3’ untranslated region of BMP8A, a member of the bone morphogenic protein (BMP) gene family. Further investigation revealed several variants in BMP genes associated with PAD via an interaction with traffic exposure in both the EA and AA cohorts; this included interactions with non-synonymous variants in BMP2, which is regulated by air pollution exposure. The BMP family of genes is linked to vascular growth and calcification and is a novel gene family for the study of PAD pathophysiology. Further investigation of BMP8A using the Genotype Tissue Expression Database revealed multiple variants with nominally significant (P < 0.05) interaction P-values in our EA cohort were significant BMP8A eQTLs in tissue types highlight relevant for PAD such as rs755249 (tibial nerve, eQTL P = 3.6x10-6) and rs1180341 (tibial artery, eQTL P = 5.3x10-6). Together these results reveal a novel gene, and possibly gene family, associated with PAD via an interaction with traffic air pollution exposure. These results also highlight the potential for interactions studies, particularly at the genome scale, to reveal novel biology linking environmental exposures to clinical outcomes.
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Young JC, Wakitani S, Loveland KL. TGF-β superfamily signaling in testis formation and early male germline development. Semin Cell Dev Biol 2015; 45:94-103. [PMID: 26500180 DOI: 10.1016/j.semcdb.2015.10.029] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 10/16/2015] [Indexed: 12/11/2022]
Abstract
The TGF-β ligand superfamily contains at least 40 members, many of which are produced and act within the mammalian testis to facilitate formation of sperm. Their progressive expression at key stages and in specific cell types determines the fertility of adult males, influencing testis development and controlling germline differentiation. BMPs are essential for the interactive instructions between multiple cell types in the early embryo that drive initial specification of gamete precursors. In the nascent foetal testis, several ligands including Nodal, TGF-βs, Activins and BMPs, serve as key masculinizing switches by regulating male germline pluripotency, somatic and germline proliferation, and testicular vascularization and architecture. In postnatal life, local production of these factors determine adult testis size by regulating Sertoli cell multiplication and differentiation, in addition to specifying germline differentiation and multiplication. Because TGF-β superfamily signaling is integral to testis formation, it affects processes that underlie testicular pathologies, including testicular cancer, and its potential to contribute to subfertility is beginning to be understood.
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Affiliation(s)
- Julia C Young
- Hudson Institute of Medical Research, Clayton, Victoria, Australia; Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Shoichi Wakitani
- Hudson Institute of Medical Research, Clayton, Victoria, Australia; Laboratory of Veterinary Biochemistry and Molecular Biology, University of Miyazaki, Japan
| | - Kate L Loveland
- Hudson Institute of Medical Research, Clayton, Victoria, Australia; School of Clinical Sciences, Monash University, Clayton, Victoria, Australia; Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia.
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Manku G, Culty M. Dynamic changes in the expression of apoptosis-related genes in differentiating gonocytes and in seminomas. Asian J Androl 2015; 17:403-14. [PMID: 25677133 PMCID: PMC4430938 DOI: 10.4103/1008-682x.146101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 11/24/2014] [Accepted: 11/26/2014] [Indexed: 01/25/2023] Open
Abstract
Apoptosis is an integral part of the spermatogenic process, necessary to maintain a proper ratio of Sertoli to germ cell numbers and provide an adequate microenvironment to germ cells. Apoptosis may also represent a protective mechanism mediating the elimination of abnormal germ cells. Extensive apoptosis occurs between the first and second postnatal weeks, at the point when gonocytes, precursors of spermatogonial stem cells, should have migrated toward the basement membrane of the tubules and differentiated into spermatogonia. The mechanisms regulating this process are not well-understood. Gonocytes undergo phases of proliferation, migration, and differentiation which occur in a timely and closely regulated manner. Gonocytes failing to migrate and differentiate properly undergo apoptosis. Inadequate gonocyte differentiation has been suggested to lead to testicular germ cell tumor (TGCT) formation. Here, we examined the expression levels of apoptosis-related genes during gonocyte differentiation by quantitative real-time polymerase chain reaction, identifying 48 pro- and anti-apoptotic genes increased by at least two-fold in rat gonocytes induced to differentiate by retinoic acid, when compared to untreated gonocytes. Further analysis of the most highly expressed genes identified the pro-apoptotic genes Gadd45a and Cycs as upregulated in differentiating gonocytes and in spermatogonia compared with gonocytes. These genes were also significantly downregulated in seminomas, the most common type of TGCT, compared with normal human testicular tissues. These results indicate that apoptosis-related genes are actively regulated during gonocyte differentiation. Moreover, the down-regulation of pro-apoptotic genes in seminomas suggests that they could represent new therapeutic targets in the treatment of TGCTs.
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Affiliation(s)
- Gurpreet Manku
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
- Department of Medicine, McGill University, Montreal, Quebec, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada
| | - Martine Culty
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
- Department of Medicine, McGill University, Montreal, Quebec, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada
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10
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Azpiazu R, Amaral A, Castillo J, Estanyol JM, Guimerà M, Ballescà JL, Balasch J, Oliva R. High-throughput sperm differential proteomics suggests that epigenetic alterations contribute to failed assisted reproduction. Hum Reprod 2014; 29:1225-37. [PMID: 24781426 DOI: 10.1093/humrep/deu073] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
STUDY QUESTION Are there quantitative alterations in the proteome of normozoospermic sperm samples that are able to complete IVF but whose female partner does not achieve pregnancy? SUMMARY ANSWER Normozoospermic sperm samples with different IVF outcomes (pregnancy versus no pregnancy) differed in the levels of at least 66 proteins. WHAT IS KNOWN ALREADY The analysis of the proteome of sperm samples with distinct fertilization capacity using low-throughput proteomic techniques resulted in the detection of a few differential proteins. Current high-throughput mass spectrometry approaches allow the identification and quantification of a substantially higher number of proteins. STUDY DESIGN, SIZE, DURATION This was a case-control study including 31 men with normozoospermic sperm and their partners who underwent IVF with successful fertilization recruited between 2007 and 2008. PARTICIPANTS/MATERIALS, SETTING, METHODS Normozoospermic sperm samples from 15 men whose female partners did not achieve pregnancy after IVF (no pregnancy) and 16 men from couples that did achieve pregnancy after IVF (pregnancy) were included in this study. To perform the differential proteomic experiments, 10 no pregnancy samples and 10 pregnancy samples were separately pooled and subsequently used for tandem mass tags (TMT) protein labelling, sodium dodecyl sulphate-polyacrylamide gel electrophoresis, liquid chromatography tandem mass spectrometry (LC-MS/MS) identification and peak intensity relative protein quantification. Bioinformatic analyses were performed using UniProt Knowledgebase, DAVID and Reactome. Individual samples (n = 5 no pregnancy samples; n = 6 pregnancy samples) and aliquots from the above TMT pools were used for western blotting. MAIN RESULTS AND THE ROLE OF CHANCE By using TMT labelling and LC-MS/MS, we have detected 31 proteins present at lower abundance (ratio no pregnancy/pregnancy < 0.67) and 35 at higher abundance (ratio no pregnancy/pregnancy > 1.5) in the no pregnancy group. Bioinformatic analyses showed that the proteins with differing abundance are involved in chromatin assembly and lipoprotein metabolism (P values < 0.05). In addition, the differential abundance of one of the proteins (SRSF protein kinase 1) was further validated by western blotting using independent samples (P value < 0.01). LIMITATIONS, REASONS FOR CAUTION For individual samples the amount of recovered sperm not used for IVF was low and in most of the cases insufficient for MS analysis, therefore pools of samples had to be used to this end. WIDER IMPLICATIONS OF THE FINDINGS Alterations in the proteins involved in chromatin assembly and metabolism may result in epigenetic errors during spermatogenesis, leading to inaccurate sperm epigenetic signatures, which could ultimately prevent embryonic development. These sperm proteins may thus possibly have clinical relevance. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by the Spanish Ministry of Economy and Competitiveness (Ministerio de Economia y Competividad; FEDER BFU 2009-07118 and PI13/00699) and Fundación Salud 2000 SERONO13-015. There are no competing interests to declare.
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Affiliation(s)
- Rubén Azpiazu
- Human Genetics Research Group, IDIBAPS, Faculty of Medicine, University of Barcelona, Casanova 143, Barcelona 08036, Spain
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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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Bilandzic M, Stenvers KL. Reprint of: Betaglycan: a multifunctional accessory. Mol Cell Endocrinol 2012; 359:13-22. [PMID: 22521265 DOI: 10.1016/j.mce.2012.03.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 04/18/2011] [Accepted: 04/18/2011] [Indexed: 12/21/2022]
Abstract
Betaglycan is a co-receptor for the TGFβ superfamily, particularly important in establishing the potency of its ligands on their target cells. In recent years, new insights have been gained into the structure and function of betaglycan, expanding its role from that of a simple co-receptor to include additional ligand-dependent and ligand-independent roles. This review focuses on recent advances in the betaglycan field, with a particular emphasis on its newly discovered actions in mediating the trafficking of TGFβ superfamily receptors and as a determinant of the functional output of TGFβ superfamily signalling. In addition, this review encompasses a discussion of the emerging roles of the betaglycan/inhibin pathway in reproductive cancers and disease.
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Affiliation(s)
- Maree Bilandzic
- Prince Henry's Institute, PO Box 5152, Clayton, Victoria 3168, Australia.
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Barakat B, Itman C, Mendis SH, Loveland KL. Activins and inhibins in mammalian testis development: new models, new insights. Mol Cell Endocrinol 2012; 359:66-77. [PMID: 22406273 DOI: 10.1016/j.mce.2012.02.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 02/20/2012] [Accepted: 02/21/2012] [Indexed: 01/15/2023]
Abstract
The discovery of activin and inhibins as modulators of the hypothalamic-pituitary-gonadal axis has set the foundation for understanding their central importance to many facets of development and disease. This review contains an overview of the processes and cell types that are central to testis development and spermatogenesis and then provides an update focussed on information gathered over the past five years to address new concepts about how these proteins function to control testis development in fetal and juvenile life. Current knowledge about the interactive nature of the transforming growth factor-β (TGFβ) superfamily signalling network is applied to recent findings about activins and inhibins in the testis. Information about the regulated synthesis of signalling components and signalling regulators in the testis is integrated with new concepts that demonstrate their functional significance. The importance of activin bioactivity levels or dosage in controlling balanced growth of spermatogonial cells and their niche at different stages of testis development is highlighted.
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Affiliation(s)
- B Barakat
- Monash Institute of Reproduction and Development, Monash University, Clayton, Victoria, Australia
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Abstract
The blood-testis barrier (BTB) is one of the tightest blood-tissue barriers in the mammalian body. It divides the seminiferous epithelium into the basal and the apical (adluminal) compartments. Meiosis I and II, spermiogenesis, and spermiation all take place in a specialized microenvironment behind the BTB in the apical compartment, but spermatogonial renewal and differentiation and cell cycle progression up to the preleptotene spermatocyte stage take place outside of the BTB in the basal compartment of the epithelium. However, the BTB is not a static ultrastructure. Instead, it undergoes extensive restructuring during the seminiferous epithelial cycle of spermatogenesis at stage VIII to allow the transit of preleptotene spermatocytes at the BTB. Yet the immunological barrier conferred by the BTB cannot be compromised, even transiently, during the epithelial cycle to avoid the production of antibodies against meiotic and postmeiotic germ cells. Studies have demonstrated that some unlikely partners, namely adhesion protein complexes (e.g., occludin-ZO-1, N-cadherin-β-catenin, claudin-5-ZO-1), steroids (e.g., testosterone, estradiol-17β), nonreceptor protein kinases (e.g., focal adhesion kinase, c-Src, c-Yes), polarity proteins (e.g., PAR6, Cdc42, 14-3-3), endocytic vesicle proteins (e.g., clathrin, caveolin, dynamin 2), and actin regulatory proteins (e.g., Eps8, Arp2/3 complex), are working together, apparently under the overall influence of cytokines (e.g., transforming growth factor-β3, tumor necrosis factor-α, interleukin-1α). In short, a "new" BTB is created behind spermatocytes in transit while the "old" BTB above transiting cells undergoes timely degeneration, so that the immunological barrier can be maintained while spermatocytes are traversing the BTB. We also discuss recent findings regarding the molecular mechanisms by which environmental toxicants (e.g., cadmium, bisphenol A) induce testicular injury via their initial actions at the BTB to elicit subsequent damage to germ-cell adhesion, thereby leading to germ-cell loss, reduced sperm count, and male infertility or subfertility. Moreover, we also critically evaluate findings in the field regarding studies on drug transporters in the testis and discuss how these influx and efflux pumps regulate the entry of potential nonhormonal male contraceptives to the apical compartment to exert their effects. Collectively, these findings illustrate multiple potential targets are present at the BTB for innovative contraceptive development and for better delivery of drugs to alleviate toxicant-induced reproductive dysfunction in men.
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Affiliation(s)
- C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, USA.
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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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Moore BC, Milnes MR, Kohno S, Katsu Y, Iguchi T, Woodruff TK, Guillette LJ. Altered gonadal expression of TGF-β superfamily signaling factors in environmental contaminant-exposed juvenile alligators. J Steroid Biochem Mol Biol 2011; 127:58-63. [PMID: 21251980 DOI: 10.1016/j.jsbmb.2011.01.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2010] [Revised: 01/05/2011] [Accepted: 01/10/2011] [Indexed: 11/29/2022]
Abstract
Environmental contaminant exposure can influence gonadal steroid signaling milieus; however, little research has investigated the vulnerability of non-steroidal signaling pathways in the gonads. Here we use American alligators (Alligator mississippiensis) hatched from field-collected eggs to analyze gonadal mRNA transcript levels of the activin-inhibin-follistatin gene expression network and growth differentiation factor 9. The eggs were collected from Lake Woodruff National Wildlife Refuge, a site with minimal anthropogenic influence, and Lake Apopka, a highly contaminated lake adjacent to a former EPA Superfund site. The hatchling alligators were raised for 13 months under controlled conditions, thus limiting differences to embryonic origins. Our data reveal sexually dimorphic mRNA expression in 13-month-old alligator gonads similar to patterns established in vertebrates with genetic sex determination. In addition, we observed a relationship between lake of origin and mRNA expression of activin/inhibin subunits α and βB, follistatin, and growth differentiation factor 9. Our study suggests that embryonic exposure to environmental contaminants can affect future non-steroidal signaling patterns in the gonads of a long-lived species.
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Affiliation(s)
- Brandon C Moore
- Department of Biology, University of Florida, Gainesville, FL 32611-8525, USA.
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Bilandzic M, Stenvers KL. Betaglycan: a multifunctional accessory. Mol Cell Endocrinol 2011; 339:180-9. [PMID: 21550381 DOI: 10.1016/j.mce.2011.04.014] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 04/18/2011] [Accepted: 04/18/2011] [Indexed: 10/18/2022]
Abstract
Betaglycan is a co-receptor for the TGFβ superfamily, particularly important in establishing the potency of its ligands on their target cells. In recent years, new insights have been gained into the structure and function of betaglycan, expanding its role from that of a simple co-receptor to include additional ligand-dependent and ligand-independent roles. This review focuses on recent advances in the betaglycan field, with a particular emphasis on its newly discovered actions in mediating the trafficking of TGFβ superfamily receptors and as a determinant of the functional output of TGFβ superfamily signalling. In addition, this review encompasses a discussion of the emerging roles of the betaglycan/inhibin pathway in reproductive cancers and disease.
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Affiliation(s)
- Maree Bilandzic
- Prince Henry's Institute, P.O. Box 5152, Clayton, Victoria 3168, Australia.
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18
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Meinhardt A, Hedger MP. Immunological, paracrine and endocrine aspects of testicular immune privilege. Mol Cell Endocrinol 2011; 335:60-8. [PMID: 20363290 DOI: 10.1016/j.mce.2010.03.022] [Citation(s) in RCA: 167] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Accepted: 03/26/2010] [Indexed: 02/06/2023]
Abstract
Protection of the spermatogenic cells from the host immune response is fundamental to male fertility. Significantly, this protection extends to the tolerance of foreign tissue grafts placed within the testicular environment, a phenomenon that is called 'immune privilege'. This privilege of the testis appears to involve several levels of immune control, encompassing the normal mechanisms of immune tolerance, antigen sequestration behind the blood-testis barrier, reduced immune activation, localised immunosuppression and antigen-specific immunoregulation. Central to these regulatory processes are the somatic cells of the testis, particularly the Sertoli cells, and testicular secretions, including androgens, cytokines, peptides and bioactive lipids. Failure of these protective mechanisms, which may be precipitated by trauma, inflammation or infection, or as the consequence of genetic factors, can lead to androgen deficiency, infertility and autoimmunity.
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Affiliation(s)
- Andreas Meinhardt
- Department of Anatomy and Cell Biology, Justus-Liebig-University of Giessen, Aulweg 123, 35385 Giessen, Germany.
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19
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Abstract
Spermiation--the release of mature spermatozoa from Sertoli cells into the seminiferous tubule lumen--occurs by the disruption of an anchoring device known as the apical ectoplasmic specialization (apical ES). At the same time, the blood-testis barrier (BTB) undergoes extensive restructuring to facilitate the transit of preleptotene spermatocytes. While these two cellular events take place at opposite ends of the Sertoli cell epithelium, the events are in fact tightly coordinated, as any disruption in either process will lead to infertility. A local regulatory axis exists between the apical ES and the BTB in which biologically active laminin fragments produced at the apical ES by the action of matrix metalloproteinase 2 can regulate BTB restructuring directly or indirectly via the hemidesmosome. Equally important, polarity proteins play a crucial part in coordinating cellular events within this apical ES-BTB-hemidesmosome axis. Additionally, testosterone and cytokines work in concert to facilitate BTB restructuring, which enables the transit of spermatocytes while maintaining immunological barrier function. Herein, we will discuss this important autocrine-based cellular axis that parallels the hormonal-based hypothalamic-pituitary-testicular axis that regulates spermatogenesis. This local regulatory axis is the emerging target for male contraception.
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Affiliation(s)
- C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, USA.
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Stenvers KL, Findlay JK. Inhibins: from reproductive hormones to tumor suppressors. Trends Endocrinol Metab 2010; 21:174-80. [PMID: 20005735 DOI: 10.1016/j.tem.2009.11.009] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 11/23/2009] [Accepted: 11/23/2009] [Indexed: 11/30/2022]
Abstract
Inhibins are peptide hormones shown originally to be produced by the gonads to regulate the secretion of follicle stimulating hormone by pituitary gonadotropes. Although gonadotropes have been regarded as the canonical inhibin target cells, in recent years extrapituitary actions of inhibins have come into the spotlight. In particular, disruptions to the local actions of inhibins in peripheral tissues might underlie certain diseases, especially cancers of the reproductive tract. This review focuses on recent advances in the inhibin field, with a particular emphasis on the determinants of inhibin availability, mechanisms of inhibin action, and the physiological relevancy of local inhibin actions in the development and progression of reproductive cancers.
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Affiliation(s)
- Kaye L Stenvers
- Prince Henry's Institute of Medical Research, Clayton, Victoria 3168 Australia.
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Cheng CY, Wong EWP, Yan HHN, Mruk DD. Regulation of spermatogenesis in the microenvironment of the seminiferous epithelium: new insights and advances. Mol Cell Endocrinol 2010; 315:49-56. [PMID: 19682538 PMCID: PMC3516447 DOI: 10.1016/j.mce.2009.08.004] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Accepted: 08/04/2009] [Indexed: 11/20/2022]
Abstract
Spermatogenesis is a complex biochemical event, involving the participation of the hypothalamus and the pituitary gland via secretion of the hypothalamus hormone GnRH, and two pituitary hormones FSH and LH. Thus, the hypothalamic-pituitary-testicular axis is a crucial regulatory axis for testicular function. Recent studies have shown that in the microenvironment of the seminiferous epithelium, wherein each Sertoli cell supports approximately 30-50 germ cells at different stages of development, locally produced autocrine and paracrine factors are also involved in spermatogenesis, in particular at the level of cell junctions. These cell junctions at the Sertoli-Sertoli and Sertoli-germ cell interface are crucial for coordinating different events of spermatogenesis by sending signals back-and-forth between Sertoli and germ cells, in order to precisely regulate spermatogonial cell renewal by mitosis, cell cycle progression, meiosis, spermiogenesis, germ cell movement across the epithelium, spermiation and germ cell apoptosis. In this minireview, we provide an update on these latest findings for an emerging new concept regarding the presence of a local "apical ectoplasmic specialization-blood-testis barrier-hemidesmosome/basement membrane" functional axis that regulates the events of spermiation and blood-testis barrier (BTB) restructuring via paracrine/autocrine factors and polarity proteins produced locally in the seminiferous epithelium. These findings provide a new window of research for investigators in the field to tackle the functional regulation of spermatogenesis.
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Affiliation(s)
- C Yan Cheng
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, USA.
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22
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Moore BC, Hamlin HJ, Botteri NL, Guillette LJ. Gonadal mRNA expression levels of TGFbeta superfamily signaling factors correspond with post-hatching morphological development in American alligators. Sex Dev 2010; 4:62-72. [PMID: 20110644 DOI: 10.1159/000277934] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2009] [Accepted: 05/13/2009] [Indexed: 11/19/2022] Open
Abstract
Paracrine factor signaling regulates many aspects of vertebrate gonadal development. We investigated key ovarian and testicular morphological markers of the American alligator (Alligator mississippiensis) during the first 5 months post-hatching and correlated gonadal development with mRNA expression levels of a suite of regulatory factors. In both sexes, we observed significant morphology changes, including ovarian follicle assembly and meiotic progression of testicular germ cells. Concomitant with these changes were sexually dimorphic and ontogenetically variable mRNA expressions. In ovaries, FOXL2, aromatase, and follistatin mRNA expression was greater than in testes at all ages. At one week after hatching, we observed ovarian medullary remodeling in association with elevated activin/inhibin beta A subunit, follistatin, and aromatase mRNA expressions. Three and 5 months following hatching and concomitant with follicle assembly, ovaries showed increased mRNA expression levels of GDF9 and the mitotic factor PCNA. In testes, the activin/inhibin alpha and beta B subunit transcript levels were greater than in ovaries at all ages. Elevated testicular expression of GDF9 mRNA levels at 5 months after hatching aligned with increased spermatogenic activity. We propose that the mRNA expression levels and concomitant morphological changes observed here affect the establishment of alligator reproductive health and later fertility.
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Affiliation(s)
- B C Moore
- Department of Biology, Bartram Hall, University of Florida, Gainesville, FL, USA. bmoore2 @ tulane.edu
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Cheng CY, Mruk DD. An intracellular trafficking pathway in the seminiferous epithelium regulating spermatogenesis: a biochemical and molecular perspective. Crit Rev Biochem Mol Biol 2009; 44:245-63. [PMID: 19622063 PMCID: PMC2758293 DOI: 10.1080/10409230903061207] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
During spermatogenesis in adult rat testes, fully developed spermatids (i.e. spermatozoa) at the luminal edge of the seminiferous epithelium undergo "spermiation" at stage VIII of the seminiferous epithelial cycle. This is manifested by the disruption of the apical ectoplasmic specialization (apical ES) so that spermatozoa can enter the tubule lumen and to complete their maturation in the epididymis. At the same time, the blood-testis barrier (BTB) located near the basement membrane undergoes extensive restructuring to allow transit of preleptotene spermatocytes so that post-meiotic germ cells complete their development behind the BTB. While spermiation and BTB restructuring take place concurrently at opposite ends of the Sertoli cell epithelium, the biochemical mechanism(s) by which they are coordinated were not known until recently. Studies have shown that fragments of laminin chains are generated from the laminin/integrin protein complex at the apical ES via the action of MMP-2 (matrix metalloprotease-2) at spermiation. These peptides serve as the local autocrine factors to destabilize the BTB. These laminin peptides also exert their effects on hemidesmosome which, in turn, further potentiates BTB restructuring. Thus, a novel apical ES-BTB-hemidesmosome regulatory loop is operating in the seminiferous epithelium to coordinate these two crucial cellular events of spermatogenesis. This functional loop is further assisted by the Par3/Par6-based polarity protein complex in coordination with cytokines and testosterone at the BTB. Herein, we provide a critical review based on the latest findings in the field regarding the regulation of these cellular events. These recent findings also open up a new window for investigators studying blood-tissue barriers.
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Affiliation(s)
- C Yan Cheng
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, New York 10065, USA.
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Mithraprabhu S, Loveland KL. Control of KIT signalling in male germ cells: what can we learn from other systems? Reproduction 2009; 138:743-57. [PMID: 19567460 DOI: 10.1530/rep-08-0537] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The KIT ligand (KITL)/KIT-signalling system is among several pathways known to be essential for fertility. In the postnatal testis, the KIT/KITL interaction is crucial for spermatogonial proliferation, differentiation, survival and subsequent entry into meiosis. Hence, identification of endogenous factors that regulate KIT synthesis is important for understanding the triggers driving germ cell maturation. Although limited information is available regarding local factors in the testicular microenvironment that modulate KIT synthesis at the onset of spermatogenesis, knowledge from other systems could be used as a basis for identifying how KIT function is regulated in germ cells. This review describes the known regulators of KIT, including transcription factors implicated in KIT promoter regulation. In addition, specific downstream outcomes in biological processes that KIT orchestrates are addressed. These are discussed in relationship to current knowledge of mammalian germ cell development.
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Affiliation(s)
- Sridurga Mithraprabhu
- Monash Institute for Medical Research, Monash University, Clayton, Victoria, Australia
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Nicholls PK, Harrison CA, Gilchrist RB, Farnworth PG, Stanton PG. Growth differentiation factor 9 is a germ cell regulator of Sertoli cell function. Endocrinology 2009; 150:2481-90. [PMID: 19106224 DOI: 10.1210/en.2008-1048] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Oocyte-secreted growth differentiation factor (GDF) 9 and bone morphogenetic protein (BMP) 15 are critical regulatory factors in female reproduction. Together, they promote granulosa cell proliferation and stimulate the maturation of preovulatory follicles. Despite their importance in female fertility, GDF9 and BMP15 expression patterns and function during spermatogenesis have not been investigated. In this study we show that the expression and stage-specific localization of both factors are limited to the germ cells of the rat seminiferous epithelium, with GDF9 being principally localized in round spermatids and BMP15 in gonocytes and pachytene spermatocytes. To identify potential cellular targets for GDF9 actions, cells of the seminiferous tubule were isolated and screened for the expression of signaling receptors [activin-like kinase (ALK) 5, ALK6, and BMP receptor, type II)]. Individual receptor types were expressed throughout the seminiferous epithelium, but coexpression of ALK5 and BMP receptor, type II was limited to Sertoli cells and round spermatids. Based on the reproductive actions of related TGFbeta ligands in the ovary and testis, GDF9 was assessed for its ability to regulate tight junction function and inhibin B production in rat Sertoli cell cultures. When recombinant mouse GDF9 was added to immature Sertoli cell cultures, it inhibited membrane localization of the junctional proteins claudin-11, occludin, and zonula occludens-1, thereby disrupting tight junction integrity. Concomitantly, GDF9 up-regulated inhibin subunit expression and significantly stimulated dimeric inhibin B protein production. Together, these results demonstrate that GDF9 and BMP15 are germ cell-specific factors in the rat testis, and that GDF9 can modulate key Sertoli cell functions.
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Affiliation(s)
- Peter K Nicholls
- Prince Henry's Institute of Medical Research, P.O. Box 5152, Clayton 3168, Victoria, Australia
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Papakonstantinou T, Harris SJ, Fredericks D, Harrison C, Wallace EM, Hearn MTW. Synthesis, purification and bioactivity of recombinant human activin A expressed in the yeast Pichia pastoris. Protein Expr Purif 2008; 64:131-8. [PMID: 19027859 DOI: 10.1016/j.pep.2008.10.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Revised: 10/05/2008] [Accepted: 10/07/2008] [Indexed: 10/21/2022]
Abstract
The transforming growth factor-beta (TGF-beta) superfamily member, activin A, plays a central role in the regulation of multiple physiological processes including cell differentiation, mitogenesis, embryogenesis, apoptosis and inflammation. In normal cells, activin A signalling is regulated to maintain cellular and tissue health and suppress tumour growth. Disruption of activin A signalling has been implicated in tumour formation and progression. Hence, the availability of activin A is an important target for the development of diagnostics and drugs for therapeutic intervention. To this end, we have expressed human activin A in Pichia pastoris, permitting its secretion into culture medium and purification as the mature homodimer. A construct was engineered encoding the monomeric precursor protein with a N-terminal FLAG affinity tag (DYKDDDDK) and a cleavage site (EKR) for Kex2p protease. Procedures for the two-step purification of human activin A by ion-exchange and anti-FLAG antibody affinity chromatography, and for the removal of the FLAG affinity tag from purified recombinant human activin A by enteropeptidase, are described. The molecular weights of the FLAG-tagged and de-tagged human activin A were confirmed by MALDI-TOF mass spectroscopy. The biological activity of these recombinant activins was assessed for their effects on modulating the secretion of Endothelin-1 (ET-1) by human umbilical vein endothelial cells (HUVECs). The recombinant human activin A containing the intact FLAG tag resulted in a reduced ET-1 secretion from HUVECs, whereas upon removal of this affinity purification tag the purified recombinant human activin A restored ET-1 secretion to levels comparable to the positive control. These results document an approach of considerable potential for the simple, large-scale expression and purification of this important human growth factor for use in diagnostic and therapeutic purposes.
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Affiliation(s)
- Theo Papakonstantinou
- ARC Special Research Centre for Green Chemistry, Building 75, Monash University, Clayton, Victoria 3800, Australia
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29
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Rajpert-De Meyts E. Recent advances and future directions in research on testicular germ cell cancer. ACTA ACUST UNITED AC 2007; 30:192-7. [PMID: 17705803 DOI: 10.1111/j.1365-2605.2007.00810.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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