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Campos RK, Liang Y, Azar SR, Ly J, Camargos VN, Hager-Soto EE, Eyzaguirre E, Sun J, Rossi SL. CD8 + T cell response promotes viral clearance and reduces chances of severe testicular damage in mouse models of long-term Zika virus infection of the testes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.22.575592. [PMID: 38328060 PMCID: PMC10849515 DOI: 10.1101/2024.01.22.575592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Zika virus (ZIKV) causes human testicular inflammation and alterations in sperm parameters and causes testicular damage in mouse models. The involvement of individual immune cells in testicular damage is not fully understood. We detected virus in the testes of the interferon (IFN) α/β receptor -/- A129 mice three weeks post-infection and found elevated chemokines in the testes, suggesting chronic inflammation and long-term infection play a role in testicular damage. In the testes, myeloid cells and CD4 + T cells were absent at 7 dpi but were present at 23 days post-infection (dpi), and CD8 + T cell infiltration started at 7 dpi. CD8 -/- mice with an antibody-depleted IFN response had a significant reduction in spermatogenesis, indicating that CD8 + T cells are essential to prevent testicular damage during long-term ZIKV infections. Our findings on the dynamics of testicular immune cells and importance of CD8 + T cells functions as a framework to understand mechanisms underlying observed inflammation and sperm alterations in humans.
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Zhang MF, Wan SC, Chen WB, Yang DH, Liu WQ, Li BL, Aierken A, Du XM, Li YX, Wu WP, Yang XC, Wei YD, Li N, Peng S, Li XL, Li GP, Hua JL. Transcription factor Dmrt1 triggers the SPRY1-NF-κB pathway to maintain testicular immune homeostasis and male fertility. Zool Res 2023; 44:505-521. [PMID: 37070575 PMCID: PMC10236308 DOI: 10.24272/j.issn.2095-8137.2022.440] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 04/07/2023] [Indexed: 04/19/2023] Open
Abstract
Bacterial or viral infections, such as Brucella, mumps virus, herpes simplex virus, and Zika virus, destroy immune homeostasis of the testes, leading to spermatogenesis disorder and infertility. Of note, recent research shows that SARS-CoV-2 can infect male gonads and destroy Sertoli and Leydig cells, leading to male reproductive dysfunction. Due to the many side effects associated with antibiotic therapy, finding alternative treatments for inflammatory injury remains critical. Here, we found that Dmrt1 plays an important role in regulating testicular immune homeostasis. Knockdown of Dmrt1 in male mice inhibited spermatogenesis with a broad inflammatory response in seminiferous tubules and led to the loss of spermatogenic epithelial cells. Chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq) revealed that Dmrt1 positively regulated the expression of Spry1, an inhibitory protein of the receptor tyrosine kinase (RTK) signaling pathway. Furthermore, immunoprecipitation-mass spectrometry (IP-MS) and co-immunoprecipitation (Co-IP) analysis indicated that SPRY1 binds to nuclear factor kappa B1 (NF-κB1) to prevent nuclear translocation of p65, inhibit activation of NF-κB signaling, prevent excessive inflammatory reaction in the testis, and protect the integrity of the blood-testis barrier. In view of this newly identified Dmrt1- Spry1-NF-κB axis mechanism in the regulation of testicular immune homeostasis, our study opens new avenues for the prevention and treatment of male reproductive diseases in humans and livestock.
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Affiliation(s)
- Meng-Fei Zhang
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Shi-Cheng Wan
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Wen-Bo Chen
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Dong-Hui Yang
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Wen-Qing Liu
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
- Center of Reproductive Medicine, Amsterdam Research Institute Reproduction and Development, Academic Medical Center, University of Amsterdam 1105AZ, Amsterdam, Netherlands
| | - Ba-Lun Li
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Aili Aierken
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xiao-Min Du
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yun-Xiang Li
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Wen-Ping Wu
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xin-Chun Yang
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yu-Dong Wei
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Na Li
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Sha Peng
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Xue-Ling Li
- Key Laboratory for Mammalian Reproductive Biology and Biotechnology, Ministry of Education, Inner Mongolia University, Hohhot, Inner Mongolia 010021, China
| | - Guang-Peng Li
- Key Laboratory for Mammalian Reproductive Biology and Biotechnology, Ministry of Education, Inner Mongolia University, Hohhot, Inner Mongolia 010021, China
| | - Jin-Lian Hua
- College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
- Key Laboratory of Livestock Biology, Northwest A&F University, Yangling, Shaanxi 712100, China. E-mail:
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Mechanisms underlying impaired spermatogenic function in orchitis induced by busulfan. Reprod Toxicol 2023; 115:1-7. [PMID: 36372306 DOI: 10.1016/j.reprotox.2022.11.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 10/29/2022] [Accepted: 11/08/2022] [Indexed: 11/13/2022]
Abstract
Busulfan is an alkylating agent commonly used in cancer chemotherapy. It is also an ideal agent for preparing transplant recipients of spermatogonial stem cells because of its high efficiency in destroying endogenous germ cells in the testis. However, its toxicity mechanism remains unclear, affecting its clinical use and applications. Based on reports of busulfan causing orchitis and a previous study by our team, this article summarizes the relationship between busulfan and orchitis, cytokines, the blood-testis barrier, and the cytoskeleton, unravels the regulatory pathways and mechanism behind busulfan-induced orchitis, and reveals the molecular mechanism underlying impaired spermatogenic function in orchitis, providing new ideas for the clinical application of busulfan while reducing its testicular toxicity.
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Understanding the Underlying Molecular Mechanisms of Meiotic Arrest during In Vitro Spermatogenesis in Rat Prepubertal Testicular Tissue. Int J Mol Sci 2022; 23:ijms23115893. [PMID: 35682573 PMCID: PMC9180380 DOI: 10.3390/ijms23115893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/18/2022] [Accepted: 05/22/2022] [Indexed: 12/10/2022] Open
Abstract
In vitro spermatogenesis appears to be a promising approach to restore the fertility of childhood cancer survivors. The rat model has proven to be challenging, since germ cell maturation is arrested in organotypic cultures. Here, we report that, despite a meiotic entry, abnormal synaptonemal complexes were found in spermatocytes, and in vitro matured rat prepubertal testicular tissues displayed an immature phenotype. RNA-sequencing analyses highlighted up to 600 differentially expressed genes between in vitro and in vivo conditions, including genes involved in blood-testis barrier (BTB) formation and steroidogenesis. BTB integrity, the expression of two steroidogenic enzymes, and androgen receptors were indeed altered in vitro. Moreover, most of the top 10 predicted upstream regulators of deregulated genes were involved in inflammatory processes or immune cell recruitment. However, none of the three anti-inflammatory molecules tested in this study promoted meiotic progression. By analysing for the first time in vitro matured rat prepubertal testicular tissues at the molecular level, we uncovered the deregulation of several genes and revealed that defective BTB function, altered steroidogenic pathway, and probably inflammation, could be at the origin of meiotic arrest.
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Pan Z, Gao Y, Liu S, Ke Z, Guo J, Ma W, Cui T, Liu B, Zhang X. Wu-Zi-Yan-Zong-Wan protects mouse blood-testis barrier from Tripterygium wilfordii Hook. f. multiglycoside-induced disruption by regulating proinflammatory cytokines. JOURNAL OF ETHNOPHARMACOLOGY 2021; 280:114440. [PMID: 34293456 DOI: 10.1016/j.jep.2021.114440] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 07/05/2021] [Accepted: 07/17/2021] [Indexed: 06/13/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Wu-Zi-Yan-Zong-Wan (WZYZW) is a classical traditonal Chinese herbal formula and a Chinese patent medicine used to treat male infertility. However, the chemical components of WZYZW and its mechanism are not yet fully clarified. AIM OF THE STUDY The purpose of this study is to observe the effect and underlying mechanism of WZYZW on ameliorating blood-testis barrier (BTB) dysfunction in mice with spermatogenic dysfunction induced by administration of Tripterygium wilfordii Hook. f. multiglycosides (GTW). MATERIALS AND METHODS WZYZW was administered by gavage to mice with GTW-induced spermatogenic dysfunction (kidney essence deficiency pattern) for 40 days. Testis tissues were obtained for subsequent histopathological analysis. Biotin tracing was used to evaluate the permeability of Sertoli cell tight junctions. The levels of proinflammatory cytokines including interleukin (IL)-6, IL-17A, IL-1α and tumor necrosis factor (TNF)-α were analyzed by ELISA. The expression levels of proteins related to tight junction including ZO-1, JAM-A and occludin were analyzed by western blotting. The ultrastructures of tight junctions were observed by transmission electron microscopy. RESULTS WZYZW ameliorated GTW-induced testicular spermatogenic dysfunction. Levels of IL-6, IL-17A, IL-1α, and TNF-α in the groups receiving low, medium, and high doses of WZYZW decreased in a dose-dependent manner. WZYZW impeded a biotin tracer from permeating the BTB, protecting its integrity in GTW-treated mice. In addition, our results showed no significant changes in the protein expressions of ZO-1, JAM-A, and occludin after WZYZW administration compared with the GTW group. Meanwhile, WZYZW exhibited a linear arrangement and restored the typical "sandwich" structure of BTB. No acute poisoning incidences were observed in all groups during the experiment. CONCLUSIONS Our findings demonstrate that WZYZW may ameliorate some GTW-induced BTB dysfunction, possibly by regulating proinflammatory cytokine levels. In vitro studies on the regulation of BTB permeability by WZYZW and its active components are further required.
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Affiliation(s)
- Zhenkun Pan
- Graduate School of Beijing University of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China; Department of Andrology, China-Japan Friendship Hospital, Beijing, 100029, China.
| | - Yunxiao Gao
- Department of Andrology, China-Japan Friendship Hospital, Beijing, 100029, China.
| | - Shuang Liu
- Department of Pharmacy, First People's Hospital of Chongqing Liangjiang New District, Chongqing, 401121, China.
| | - Zhenghao Ke
- Department of Andrology, China-Japan Friendship Hospital, Beijing, 100029, China.
| | - Jianqiang Guo
- Department of Andrology, China-Japan Friendship Hospital, Beijing, 100029, China.
| | - Wenjing Ma
- Department of Andrology, China-Japan Friendship Hospital, Beijing, 100029, China.
| | - Tianwei Cui
- Institute of Basic Medical Sciences, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing 100091, China.
| | - Baoxing Liu
- Department of Andrology, China-Japan Friendship Hospital, Beijing, 100029, China.
| | - Xiuping Zhang
- Department of Gynecology, Beijing University of Chinese Medicine Third Affiliated Hospital, Beijing 100029, China.
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The Seminiferous Epithelial Cycle of Spermatogenesis: Role of Non-receptor Tyrosine Kinases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1288:1-20. [PMID: 34453729 DOI: 10.1007/978-3-030-77779-1_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Non-receptor tyrosine kinases (NRTKs) are implicated in various biological processes including cell proliferation, differentiation, survival, and apoptosis, as well as cell adhesion and movement. NRTKs are expressed in all mammals and in different cell types, with extraordinarily high expression in the testis. Their association with the plasma membrane and dynamic subcellular localization are crucial parameters in their activation and function. Many NRTKs are found in endosomal protein trafficking pathways, which suggests a novel mechanism to regulate the timely junction restructuring in the mammalian testis to facilitate spermiation and germ cell transport across the seminiferous epithelium.
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7
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Qu N, Nagahori K, Kuramasu M, Ogawa Y, Suyama K, Hayashi S, Sakabe K, Itoh M. Effect of Gosha-Jinki-Gan on Levels of Specific mRNA Transcripts in Mouse Testes after Busulfan Treatment. Biomedicines 2020; 8:biomedicines8100432. [PMID: 33086656 PMCID: PMC7603379 DOI: 10.3390/biomedicines8100432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 10/17/2020] [Indexed: 11/16/2022] Open
Abstract
With the increase in survival rates of cancer patients in recent years, infertility caused by anticancer treatments has become a significant concern for cancer survivors. Some studies have suggested that Sertoli cells play a key role in mediating testicular immunology in busulfan-induced aspermatogenesis. We recently demonstrated that Gosha-jinki-gan (TJ107), a traditional Japanese medicine, can completely recover injured spermatogenesis in mice 60 days after busulfan injection. In the present study, we sought to examine the levels of mRNA transcripts encoding markers of 25 Sertoli cell-specific products and 10 markers of germ cell differentiation. Our results demonstrated that only supplementation of TJ107 at day 60 after busulfan injection could significantly recover the increase in five mRNA species (Amh, Clu, Shbg, Testin, and Il1a) and the decrease in four mRNA species (Aqp8, CST9, Wnt5a, and Tjp1) in response to Busulfan (BSF) at day 120, with the increase of all examined spermatogenic markers.
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Affiliation(s)
- Ning Qu
- Department of Anatomy, Division of Basic Medical Science, Tokai University School of Medicine, Kanagawa 259-1193, Japan; (K.S.); (S.H.); (K.S.)
- Department of Anatomy, Tokyo Medical University, Tokyo 160-8402, Japan; (K.N.); (M.K.); (Y.O.); (M.I.)
- Correspondence: or ; Tel.: +81-4-6393-1121; Fax: +81-4-6393-1517
| | - Kenta Nagahori
- Department of Anatomy, Tokyo Medical University, Tokyo 160-8402, Japan; (K.N.); (M.K.); (Y.O.); (M.I.)
| | - Miyuki Kuramasu
- Department of Anatomy, Tokyo Medical University, Tokyo 160-8402, Japan; (K.N.); (M.K.); (Y.O.); (M.I.)
| | - Yuki Ogawa
- Department of Anatomy, Tokyo Medical University, Tokyo 160-8402, Japan; (K.N.); (M.K.); (Y.O.); (M.I.)
| | - Kaori Suyama
- Department of Anatomy, Division of Basic Medical Science, Tokai University School of Medicine, Kanagawa 259-1193, Japan; (K.S.); (S.H.); (K.S.)
| | - Shogo Hayashi
- Department of Anatomy, Division of Basic Medical Science, Tokai University School of Medicine, Kanagawa 259-1193, Japan; (K.S.); (S.H.); (K.S.)
| | - Kou Sakabe
- Department of Anatomy, Division of Basic Medical Science, Tokai University School of Medicine, Kanagawa 259-1193, Japan; (K.S.); (S.H.); (K.S.)
| | - Masahiro Itoh
- Department of Anatomy, Tokyo Medical University, Tokyo 160-8402, Japan; (K.N.); (M.K.); (Y.O.); (M.I.)
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8
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Rogovskii V. Immune Tolerance as the Physiologic Counterpart of Chronic Inflammation. Front Immunol 2020; 11:2061. [PMID: 33117330 PMCID: PMC7561427 DOI: 10.3389/fimmu.2020.02061] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/29/2020] [Indexed: 12/13/2022] Open
Affiliation(s)
- Vladimir Rogovskii
- Department of Molecular Pharmacology and Radiobiology, Pirogov Russian National Research Medical University, Moscow, Russia.,Department of Neuroimmunology, Federal Center of Brain Research and Neurotechnologies, Moscow, Russia
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9
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Yang T, Yang WX. The dynamics and regulation of microfilament during spermatogenesis. Gene 2020; 744:144635. [PMID: 32244053 DOI: 10.1016/j.gene.2020.144635] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/28/2020] [Accepted: 03/30/2020] [Indexed: 12/22/2022]
Abstract
Spermatogenesis is a highly complex physiological process which contains spermatogonia proliferation, spermatocyte meiosis and spermatid morphogenesis. In the past decade, actin binding proteins and signaling pathways which are critical for regulating the actin cytoskeleton in testis had been found. In this review, we summarized 5 actin-binding proteins that have been proven to play important roles in the seminiferous epithelium. Lack of them perturbs spermatids polarity and the transport of spermatids. The loss of Arp2/3 complex, Formin1, Eps8, Palladin and Plastin3 cause sperm release failure suggesting their irreplaceable role in spermatogenesis. Actin regulation relies on multiple signal pathways. The PI3K/Akt signaling pathway positively regulate the mTOR pathway to promote actin reorganization in seminiferous epithelium. Conversely, TSC1/TSC2 complex, the upstream of mTOR, is activated by the LKB1/AMPK pathway to inhibit cell proliferation, differentiation and migration. The increasing researches focus on the function of actin binding proteins (ABPs), however, their collaborative regulation of actin patterns and potential regulatory signaling networks remains unclear. We reviewed ABPs that play important roles in mammalian spermatogenesis and signal pathways involved in the regulation of microfilaments. We suggest that more relevant studies should be performed in the future.
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Affiliation(s)
- Tong Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wan-Xi Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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10
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Li L, Li H, Wang L, Wu S, Lv L, Tahir A, Xiao X, Wong CKC, Sun F, Ge R, Cheng CY. Role of cell polarity and planar cell polarity (PCP) proteins in spermatogenesis. Crit Rev Biochem Mol Biol 2020; 55:71-87. [PMID: 32207344 DOI: 10.1080/10409238.2020.1742091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Studies on cell polarity proteins and planar cell polarity (PCP) proteins date back to almost 40 years ago in Drosophila and C. elegans when these proteins were shown to be crucial to support apico-basal polarity and also directional alignment of polarity cells across the plane of an epithelium during morphogenesis. In adult mammals, cell polarity and PCP are most notable in cochlear hair cells. However, the role of these two groups of proteins to support spermatogenesis was not explored until a decade earlier when several proteins that confer cell polarity and PCP proteins were identified in the rat testis. Since then, there are several reports appearing in the literature to examine the role of both cell polarity and PCP in supporting spermatogenesis. Herein, we provide an overview regarding the role of cell polarity and PCP proteins in the testis, evaluating these findings in light of studies in other mammalian epithelial cells/tissues. Our goal is to provide a timely evaluation of these findings, and provide some thought provoking remarks to guide future studies based on an evolving concept in the field.
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Affiliation(s)
- Linxi Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,Center for Biomedical Research, The Mary M. Wohlford Laboratory for Male Contraceptive Research, Population Council, New York, USA
| | - Huitao Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,Center for Biomedical Research, The Mary M. Wohlford Laboratory for Male Contraceptive Research, Population Council, New York, USA
| | - Lingling Wang
- Center for Biomedical Research, The Mary M. Wohlford Laboratory for Male Contraceptive Research, Population Council, New York, USA
| | - Siwen Wu
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,Center for Biomedical Research, The Mary M. Wohlford Laboratory for Male Contraceptive Research, Population Council, New York, USA
| | - Lixiu Lv
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China
| | - Anam Tahir
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China
| | - Xiang Xiao
- Department of Reproductive Physiology, Zhejiang Academy of Medical Sciences, Hangzhou, China
| | - Chris K C Wong
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Hong Kong, China
| | - Fei Sun
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, China
| | - Renshan Ge
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China
| | - C Yan Cheng
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,Center for Biomedical Research, The Mary M. Wohlford Laboratory for Male Contraceptive Research, Population Council, New York, USA
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11
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Wu H, Jiang X, Gao Y, Liu W, Wang F, Gong M, Chen R, Yu X, Zhang W, Gao B, Song C, Han D. Mumps virus infection disrupts blood-testis barrier through the induction of TNF-α in Sertoli cells. FASEB J 2019; 33:12528-12540. [PMID: 31450968 DOI: 10.1096/fj.201901089r] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Mumps virus (MuV) has high tropism to the testis and may lead to male infertility. Sertoli cells are the major targets of MuV infection. However, the mechanisms by which MuV infection impairs male fertility and Sertoli cell function remain unclear. The present study elucidated the effect of MuV infection on the blood-testis barrier (BTB). The transepithelial electrical resistance of MuV-infected mouse Sertoli cells was monitored, and the expression of major proteins of the BTB was examined. We demonstrated that MuV infection disrupted the BTB by reducing the levels of occludin and zonula occludens 1. Sertoli cells derived from Tlr2-/- and Tnfa-/- mice were analyzed for mediating MuV-induced impairment. TLR2-mediated TNF-α production by Sertoli cells in response to MuV infection impaired BTB integrity. MuV-impaired BTB was not observed in Tlr2-/- and Tnfa-/- Sertoli cells. Moreover, an inhibitor of TNF-α, pomalidomide, prevents the disruption of BTB in response to MuV infection. FITC-labeled biotin tracing assay confirmed that BTB permeability and spermatogenesis were transiently impaired by MuV infection in vivo. These findings suggest that the disruption of the BTB could be one of the mechanisms underlying MuV-impaired male fertility, in which TNF-α could play a critical role.-Wu, H., Jiang, X., Gao, Y., Liu, W., Wang, F., Gong, M., Chen, R., Yu, X., Zhang, W., Gao, B., Song, C., Han, D. Mumps virus infection disrupts blood-testis barrier through the induction of TNF-α in Sertoli cells.
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Affiliation(s)
- Han Wu
- College of Animal Science and Technology, Institute of Mobilome and Genome, Yangzhou University, Yangzhou, China.,Institute of Basic Medical Sciences, Peking Union Medical College-Chinese Academy of Medical Sciences, Beijing, China
| | - Xing Jiang
- Institute of Basic Medical Sciences, Peking Union Medical College-Chinese Academy of Medical Sciences, Beijing, China.,Guangdong Key Laboratory for Genome Stability and Disease Prevention, Shenzhen University School of Medicine, Shenzhen, China
| | - Yunxiao Gao
- Department of Andrology, China-Japan Friendship Hospital, Beijing, China
| | - Weihua Liu
- Institute of Basic Medical Sciences, Peking Union Medical College-Chinese Academy of Medical Sciences, Beijing, China
| | - Fei Wang
- Institute of Basic Medical Sciences, Peking Union Medical College-Chinese Academy of Medical Sciences, Beijing, China
| | - Maolei Gong
- Institute of Basic Medical Sciences, Peking Union Medical College-Chinese Academy of Medical Sciences, Beijing, China
| | - Ran Chen
- Institute of Basic Medical Sciences, Peking Union Medical College-Chinese Academy of Medical Sciences, Beijing, China
| | - Xiaoqin Yu
- Institute of Basic Medical Sciences, Peking Union Medical College-Chinese Academy of Medical Sciences, Beijing, China
| | - Wenjing Zhang
- Institute of Basic Medical Sciences, Peking Union Medical College-Chinese Academy of Medical Sciences, Beijing, China
| | - Bo Gao
- College of Animal Science and Technology, Institute of Mobilome and Genome, Yangzhou University, Yangzhou, China
| | - Chengyi Song
- College of Animal Science and Technology, Institute of Mobilome and Genome, Yangzhou University, Yangzhou, China
| | - Daishu Han
- Institute of Basic Medical Sciences, Peking Union Medical College-Chinese Academy of Medical Sciences, Beijing, China
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12
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He X, Sun Z, Manthari RK, Wu P, Wang J. Fluoride altered rat's blood testis barrier by affecting the F-actin via IL-1α. CHEMOSPHERE 2018; 211:826-833. [PMID: 30099167 DOI: 10.1016/j.chemosphere.2018.08.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 07/29/2018] [Accepted: 08/02/2018] [Indexed: 05/26/2023]
Abstract
Fluoride is known to affect the pro-inflammatory cytokines in the testis. Most of the recent literatures cited that cytokines regulate the blood-testis-barrier (BTB). However, the involvement of cytokines in the fluoride induced toxicity in BTB remains unclear. In order to study this, 60 male Sprague-Dawley (SD) rats were taken and randomly divided into 5 groups which included four fluoride groups exposed to 0, 25, 50, and 100 mg/L NaF in distilled water and one positive control group. On the 29th day of fluoride exposure, the positive control group rats were administered 0.1% CaCl2 solution. Biotin tracer technology and transmission electron microscopy (TEM) analysis were applied to evaluate the function and ultra-structure of BTB. The expression levels of the BTB associated proteins, actin relative protein 3 (Arp3), interleukin-1 alpha (IL-1α), and transforming growth factor beta-3 (TGF-β3) were determined using Western blotting and Enzyme Linked Immunosorbent Assay (ELISA) respectively, meanwhile the actin filament (F-actin) was detected by fluorescent phalloidin conjugates. Our results revealed that the function and the ultra-structure of BTB in all the fluoride treated groups were damaged with a concomitant significant decreases in basal ectoplasmic specialization (basal ES), associated protein β-catenin, and F-actin. Moreover, Arp3 levels were significantly increased in 50 and 100 mg/L NaF groups. Meanwhile, IL-1α significantly increased in all the fluoride treated groups. In summary, we concluded that an increase in IL-1α induced by NaF significantly decreased the expression of F-actin and the organization of F-actin highly branched, which might facilitate the BTB's functional and ultra-structural variations.
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Affiliation(s)
- Xinjin He
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, Jinzhong, Shanxi 030801, China
| | - Zilong Sun
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, Jinzhong, Shanxi 030801, China
| | - Ram Kumar Manthari
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, Jinzhong, Shanxi 030801, China
| | - Panhong Wu
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, Jinzhong, Shanxi 030801, China
| | - Jundong Wang
- Shanxi Key Laboratory of Ecological Animal Science and Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, Jinzhong, Shanxi 030801, China.
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Mang S, Braun A, Pairet N, Lamb DJ. Importance of the IL-1 Axis in Haemophilus influenzae-stimulated M 1 Macrophages Driving Transepithelial Signaling. Am J Respir Cell Mol Biol 2018; 58:412-415. [PMID: 29493324 DOI: 10.1165/rcmb.2017-0283le] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Samuel Mang
- 1 Boehringer Ingelheim Pharma GmbH & Co. KG Biberach an der Riß, Germany.,2 Hannover Medical School Hannover, Germany
| | - Armin Braun
- 2 Hannover Medical School Hannover, Germany.,3 Fraunhofer Institute for Toxicology and Experimental Medicine Hannover, Germany and
| | - Nicolas Pairet
- 1 Boehringer Ingelheim Pharma GmbH & Co. KG Biberach an der Riß, Germany.,4 University of Ulm Ulm, Germany
| | - David J Lamb
- 1 Boehringer Ingelheim Pharma GmbH & Co. KG Biberach an der Riß, Germany
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Annexin A2 is critical for blood-testis barrier integrity and spermatid disengagement in the mammalian testis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:527-545. [PMID: 27974247 DOI: 10.1016/j.bbamcr.2016.12.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 12/06/2016] [Accepted: 12/09/2016] [Indexed: 01/08/2023]
Abstract
Throughout spermatogenesis, two important processes occur at late stage VIII of the seminiferous epithelial cycle in the rat testis: preleptotene spermatocytes commence entry into the adluminal compartment and step 19 spermatids release from the seminiferous epithelium. Presently, it is not clear how these processes, which involve extensive restructuring of unique Sertoli-Sertoli and Sertoli-germ cell junctions, are mediated. We aimed to determine whether annexin A2 (ANXA2), a Ca2+-dependent and phospholipid-binding protein, participates in cell junction dynamics. To address this, in vitro and in vivo RNA interference studies were performed on prepubertal Sertoli cells and adult rat testes. The endpoints of Anxa2 knockdown were determined by immunoblotting, morphological analyses, fluorescent immunostaining, and barrier integrity assays. In the testis, ANXA2 localized to the Sertoli cell stalk, with specific staining at the blood-testis barrier and the concave (ventral) surface of elongated spermatids. ANXA2 also bound actin when testis lysates were used for immunoprecipitation. Anxa2 knockdown was found to disrupt the Sertoli cell/blood-testis barrier in vitro and in vivo. The disruption in barrier function was substantiated by changes in the localization of claudin-11, zona occludens-1, N-cadherin, and β-catenin. Furthermore, Anxa2 knockdown resulted in spermiation defects caused by a dysfunction of tubulobulbar complexes, testis-specific actin-rich ultrastructures that internalize remnant cell junction components prior to spermiation. Additionally, there were changes in the localization of several tubulobulbar complex component proteins, including actin-related protein 3, cortactin, and dynamin I/II. Our results indicate that ANXA2 is critical for the integrity of the blood-testis barrier and the timely release of spermatids.
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de Freitas ATAG, Ribeiro MA, Pinho CF, Peixoto AR, Domeniconi RF, Scarano WR. Regulatory and junctional proteins of the blood-testis barrier in human Sertoli cells are modified by monobutyl phthalate (MBP) and bisphenol A (BPA) exposure. Toxicol In Vitro 2016; 34:1-7. [DOI: 10.1016/j.tiv.2016.02.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 02/14/2016] [Accepted: 02/23/2016] [Indexed: 12/16/2022]
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Abstract
The purpose of this review is to describe the endocrine and local testicular factors that contribute to the regulation of the blood-testis barrier (BTB), using information gained from in vivo and in vitro models of BTB formation during/after puberty, and from the maintenance of BTB function during adulthood. In vivo the BTB, in part comprised of tight junctions between adjacent somatic Sertoli cells, compartmentalizes meiotic spermatocytes and post-meiotic spermatids away from the vasculature, and therefore prevents autoantibody production by the immune system against these immunogenic germ cells. This adluminal compartment also features a unique biochemical milieu required for the completion of germ cell development. During the normal process of spermatogenesis, earlier germ cells continually cross into the adluminal compartment, but the regulatory mechanisms and changes in junctional proteins that allow this translocation step without causing a 'leak' remain poorly understood. Recent data describing the roles of FSH and androgen on the regulation of Sertoli cell tight junctions and tight junction proteins will be discussed, followed by an examination of the role of paracrine factors, including members of the TGFβ superfamily (TGFβ3, activin A) and retinoid signalling, as potential mediators of junction assembly and disassembly during the translocation process.
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Affiliation(s)
- Peter G Stanton
- Hudson Institute of Medical Research, Clayton, Victoria, Australia; Dept. of Molecular and Translational Sciences, Monash University, Clayton, Victoria, Australia.
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Chojnacka K, Bilinska B, Mruk DD. Interleukin 1alpha-induced disruption of the Sertoli cell cytoskeleton affects gap junctional communication. Cell Signal 2016; 28:469-480. [DOI: 10.1016/j.cellsig.2016.02.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 02/08/2016] [Indexed: 01/09/2023]
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18
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Hayrabedyan S, Todorova K, Jabeen A, Metodieva G, Toshkov S, Metodiev MV, Mincheff M, Fernández N. Sertoli cells have a functional NALP3 inflammasome that can modulate autophagy and cytokine production. Sci Rep 2016; 6:18896. [PMID: 26744177 PMCID: PMC4705529 DOI: 10.1038/srep18896] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 11/27/2015] [Indexed: 02/07/2023] Open
Abstract
Sertoli cells, can function as non-professional tolerogenic antigen-presenting cells, and sustain the blood-testis barrier formed by their tight junctions. The NOD-like receptor family members and the NALP3 inflammasome play a key role in pro-inflammatory innate immunity signalling pathways. Limited data exist on NOD1 and NOD2 expression in human and mouse Sertoli cells. Currently, there is no data on inflammasome expression or function in Sertoli cells. We found that in primary pre-pubertal Sertoli cells and in adult Sertoli line, TLR4\NOD1 and NOD2 crosstalk converged in NFκB activation and elicited a NALP3 activation, leading to de novo synthesis and inflammasome priming. This led to caspase-1 activation and IL-1β secretion. We demonstrated this process was controlled by mechanisms linked to autophagy. NOD1 promoted pro-IL-1β restriction and autophagosome maturation arrest, while NOD2 promoted caspase-1 activation, IL-1β secretion and autophagy maturation. NALP3 modulated NOD1 and pro-IL-1β expression, while NOD2 inversely promoted IL-1β. This study is proof of concept that Sertoli cells, upon specific stimulation, could participate in male infertility pathogenesis via inflammatory cytokine induction.
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Affiliation(s)
- Soren Hayrabedyan
- Institute of Biology and Immunology of Reproduction, Laboratory of Reproductive Omics Technologies, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Krassimira Todorova
- Institute of Biology and Immunology of Reproduction, Laboratory of Reproductive Omics Technologies, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Asma Jabeen
- School of Biological Sciences, Wivenhoe Park, University of Essex, Colchester, UK
| | - Gergana Metodieva
- School of Biological Sciences, Wivenhoe Park, University of Essex, Colchester, UK
| | - Stavri Toshkov
- Cellular and Gene Therapy Ward, National Specialized Haematology Hospital, Sofia, Bulgaria
| | - Metodi V Metodiev
- School of Biological Sciences, Wivenhoe Park, University of Essex, Colchester, UK
| | - Milcho Mincheff
- Cellular and Gene Therapy Ward, National Specialized Haematology Hospital, Sofia, Bulgaria
| | - Nelson Fernández
- School of Biological Sciences, Wivenhoe Park, University of Essex, Colchester, UK
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Chojnacka K, Zarzycka M, Mruk DD. Biology of the Sertoli Cell in the Fetal, Pubertal, and Adult Mammalian Testis. Results Probl Cell Differ 2016; 58:225-251. [PMID: 27300181 DOI: 10.1007/978-3-319-31973-5_9] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A healthy man typically produces between 50 × 10(6) and 200 × 10(6) spermatozoa per day by spermatogenesis; in the absence of Sertoli cells in the male gonad, this individual would be infertile. In the adult testis, Sertoli cells are sustentacular cells that support germ cell development by secreting proteins and other important biomolecules that are essential for germ cell survival and maturation, establishing the blood-testis barrier, and facilitating spermatozoa detachment at spermiation. In the fetal testis, on the other hand, pre-Sertoli cells form the testis cords, the future seminiferous tubules. However, the role of pre-Sertoli cells in this process is much less clear than the function of Sertoli cells in the adult testis. Within this framework, we provide an overview of the biology of the fetal, pubertal, and adult Sertoli cell, highlighting relevant cell biology studies that have expanded our understanding of mammalian spermatogenesis.
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Affiliation(s)
- Katarzyna Chojnacka
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY, 10065, USA
| | - Marta Zarzycka
- Department of Endocrinology, Institute of Zoology, Jagiellonian University, Krakow, Poland
| | - Dolores D Mruk
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY, 10065, USA.
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20
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Li N, Mruk DD, Wong CKC, Lee WM, Han D, Cheng CY. Actin-bundling protein plastin 3 is a regulator of ectoplasmic specialization dynamics during spermatogenesis in the rat testis. FASEB J 2015; 29:3788-805. [PMID: 26048141 DOI: 10.1096/fj.14-267997] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 05/18/2015] [Indexed: 12/13/2022]
Abstract
Ectoplasmic specialization (ES) is an actin-rich adherens junction in the seminiferous epithelium of adult mammalian testes. ES is restricted to the Sertoli-spermatid (apical ES) interface, as well as the Sertoli cell-cell (basal ES) interface at the blood-testis barrier (BTB). ES is typified by the presence of an array of bundles of actin microfilaments near the Sertoli cell plasma membrane. These actin microfilament bundles require rapid debundling to convert them from a bundled to branched/unbundled configuration and vice versa to confer plasticity to support the transport of 1) spermatids in the adluminal compartment and 2) preleptotene spermatocytes at the BTB while maintaining cell adhesion. Plastin 3 is one of the plastin family members abundantly found in yeast, plant and animal cells that confers actin microfilaments their bundled configuration. Herein, plastin 3 was shown to be a component of the apical and basal ES in the rat testis, displaying spatiotemporal expression during the epithelial cycle. A knockdown (KD) of plastin 3 in Sertoli cells by RNA interference using an in vitro model to study BTB function showed that a transient loss of plastin 3 perturbed the Sertoli cell tight junction-permeability barrier, mediated by changes in the localization of basal ES proteins N-cadherin and β-catenin. More importantly, these changes were the result of an alteration of the actin microfilaments, converting from their bundled to branched configuration when examined microscopically, and validated by biochemical assays that quantified actin-bundling and polymerization activity. Moreover, these changes were confirmed by studies in vivo by plastin 3 KD in the testis in which mis-localization of N-cadherin and β-catenin was also detected at the BTB, concomitant with defects in the transport of spermatids and phagosomes and a disruption of cell adhesion most notably in elongated spermatids due to a loss of actin-bundling capability at the apical ES, which in turn affected localization of adhesion protein complexes at the site. In summary, plastin 3 is a regulator of actin microfilament bundles at the ES in which it dictates the configuration of the filamentous actin network by assuming either a bundled or unbundled/branched configuration via changes in its spatiotemporal expression during the epithelial cycle.
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Affiliation(s)
- Nan Li
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Dolores D Mruk
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Chris K C Wong
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Will M Lee
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Daishu Han
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - C Yan Cheng
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
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Li MW, Xiao X, Mruk DD, Lam YL, Lee WM, Lui WY, Bonanomi M, Silvestrini B, Cheng CY. Actin-binding protein drebrin E is involved in junction dynamics during spermatogenesis. SPERMATOGENESIS 2014; 1:123-136. [PMID: 22319661 DOI: 10.4161/spmg.1.2.16393] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The actin-based cytoskeleton plays a critical role in the seminiferous epithelium during spermatogenesis by conferring cell shape, adhesion, structural support and cell polarity to both Sertoli and developing germ cells, which are essential for spermatogonial stem cell renewal, maintenance of the stem cell niche, cell cycle progression, mitosis, meiosis, spermiogenesis and spermiation. However, few functional studies are found in the literature, which explore the functional significance of actin dynamics in these events. This by and large is due to a lack of information on the proteins that regulate actin dynamics. Herein, we report drebrin E is an integrated component of the apical ectoplasmic specialization (apical ES) and the basal ES at the blood-testis barrier (BTB) in the seminiferous epithelium of the adult rat testis. Using immunohistochemistry and dual-labeled immunofluorescence analysis, drebrin E was found to display a stage-specific localization at the apical ES, as well as at the basal ES at the BTB during the seminiferous epithelial cycle of spermatogenesis. Drebrin E was first detected in stage V tubules at the basal ES with the highest expression at the BTB at stages V and VI, but it diminished considerably by stages VII and VIII and was almost non-detectable until stage IV. At the apical ES, drebrin E was also first detected at stage V, surrounding the entire head of the elongating spermatid, but by stage VI its localization had "shifted" to localize most intensely and almost exclusively to the concave side of the spermatid head. In stage VII tubules, drebrin E co-localized with actin, as well as with two other actin regulatory proteins Eps8 (epidermal growth factor receptor pathway substrate 8, an actin capping and bundling protein) and Arp3 (actin-related protein 3, a component of the Arp2/3 complex known to regulate actin nucleation and branching). The localization of drebrin E at the apical ES was compromised following treatment of rats with adjudin, which is known to exert its destructive effects primarily at the apical ES by inducing premature loss of elongating/elongated spermatids from the epithelium, mimicking "spermiation." Instead of being restricted to the concave side of spermatid heads, drebrin E was found to be mis-localized in the seminiferous epithelium of adjudin-treated rats; it was also present on the convex side of elongating spermatids, but these cells were mis-oriented so that their heads no longer pointed toward the basement membrane. The expression of drebrin E by Sertoli cells was also found to be modulated by TGFβ3 and TNFα. Since Arp3, but not Eps8, was found to bind drebrin E; and cytokines were also shown to affect the cellular distribution of drebrin E and enhance the interaction between drebrin E and Arp3, these findings illustrate that cytokines may regulate BTB dynamics during the epithelial cycle by recruiting drebrin E and Arp3 to the BTB microenvironment to induce changes in the configuration of actin filament bundles at the basal ES. In summary, these findings illustrate drebrin E is working in concert with Arp3 to regulate actin filament bundles at both the apical and the basal ES in the testis, conferring adhesion and cell polarity at both sites during spermatogenesis.
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Affiliation(s)
- Michelle Wm Li
- Center for Biomedical Research; The Population Council; New York, NY USA
| | - Xiang Xiao
- Center for Biomedical Research; The Population Council; New York, NY USA
| | - Dolores D Mruk
- Center for Biomedical Research; The Population Council; New York, NY USA
| | - Yee-Ling Lam
- Center for Biomedical Research; The Population Council; New York, NY USA
| | - Will M Lee
- School of Biological Sciences; The University of Hong Kong; Hong Kong, China
| | - Wing-Yee Lui
- School of Biological Sciences; The University of Hong Kong; Hong Kong, China
| | | | | | - C Yan Cheng
- Center for Biomedical Research; The Population Council; New York, NY USA
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Mruk DD, Cheng CY. In search of suitable in vitro models to study germ cell movement across the blood-testis barrier. SPERMATOGENESIS 2014; 2:6-10. [PMID: 22553485 PMCID: PMC3341247 DOI: 10.4161/spmg.19878] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The movement of preleptotene/leptotene spermatocytes across the blood-testis barrier, also known as the Sertoli cell barrier, during stages VIII to XI of the seminiferous epithelial cycle is one of the most important cellular events taking place in the mammalian testis. Without the passage of spermatocytes, spermatogenesis would be halted, resulting in transient or permanent sterility. Unfortunately, we have very little knowledge on how preleptotene/leptotene spermatocytes cross the blood-testis barrier. While we know cytokines, proteases and androgens to mediate Sertoli cell junction restructuring, most data continue to be derived from experiments using Sertoli cells cultured alone in two dimensions. Thus, additional in vitro models which include germ cells must come into use. In this Commentary, we hope to shed new light on how we may better study spermatocyte movement across the BTB.
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Affiliation(s)
- Dolores D Mruk
- Center for Biomedical Research; The Population Council; New York, NY USA
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Su L, Kopera-Sobota IA, Bilinska B, Cheng CY, Mruk DD. Germ cells contribute to the function of the Sertoli cell barrier. SPERMATOGENESIS 2014. [DOI: 10.4161/spmg.26460] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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25
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Su L, Mruk DD, Cheng CY. Regulation of drug transporters in the testis by environmental toxicant cadmium, steroids and cytokines. SPERMATOGENESIS 2014; 2:285-293. [PMID: 23248770 PMCID: PMC3521751 DOI: 10.4161/spmg.22536] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The blood-testis barrier (BTB) provides an efficient barrier to restrict paracellular and transcellular transport of substances, such as toxicants and drugs, limiting their entry to the testis to cause injury. This is achieved by the coordinated actions of efflux and influx transporters at the BTB, which are integral membrane proteins that interact with their substrates, such as drugs and toxicants. An efflux transporter (e.g., P-glycoprotein) can either restrict the entry of drugs/toxicants into the testis or actively pump drugs/toxicants out of Sertoli and/or germ cells if they have entered the seminiferous epithelium via influx pumps. This thus provides an effective mechanism to safeguard spermatogenesis. Using Sertoli cells cultured in vitro with an established tight junction (TJ)-permeability barrier which mimicked the BTB in vivo and treated with cadmium chloride (CdCl2), and also in adult rats (~300 g b.w.) treated with CdCl2 (3 mg/kg b.w., via i.p.) to induce testicular injury, cadmium was found to significantly downregulate the expression of efflux (e.g., P-glycoprotein, Mrp1, Abcg1) and influx (e.g., Oatp3, Slc15a1, Scl39a8) transporters. For instance, treatment of Sertoli cells with cadmium induced significant loss of P-glycoprotein and Oatp-3 at the cell-cell interface, which likely facilitated cadmium entry into the Sertoli cell. These findings illustrate that one of the mechanisms by which cadmium enters the testis is mediated by downregulating the expression of drug transporters at the BTB. Furthermore, cytokines and steroids were found to have differential effects in regulating the expression of drug transporters. Summary, the expression of drug transporters in the testis is regulated by toxicants, steroids and cytokines.
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Affiliation(s)
- Linlin Su
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York, NY USA
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26
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Lydka M, Bilinska B, Cheng CY, Mruk DD. Tumor necrosis factor α-mediated restructuring of the Sertoli cell barrier in vitro involves matrix metalloprotease 9 (MMP9), membrane-bound intercellular adhesion molecule-1 (ICAM-1) and the actin cytoskeleton. SPERMATOGENESIS 2014; 2:294-303. [PMID: 23248771 PMCID: PMC3521752 DOI: 10.4161/spmg.22602] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The mammalian blood-testis barrier (BTB) restructures throughout spermatogenesis, thereby allowing developing germ cells to enter the adluminal compartment of the seminiferous epithelium. Previous studies have shown pro-inflammatory cytokines such as tumor necrosis factor α (TNFα) and interleukin-1α to be important regulators of Sertoli cell barrier/BTB function in vitro and in vivo. In this study, the effects of TNFα on Sertoli cell barrier function were assessed, with emphasis on changes in proteases and cell adhesion molecules following treatment. By immunoblotting and immunohistochemistry, MMP9 was found to be present in germ cells, localizing by and large to spermatocytes and spermatids in the adult rat testis. Following treatment of Sertoli cells with physiologically relevant consecutive doses of recombinant human TNFα (25 ng/ml), the steady-state levels of active-matrix metalloprotease 9 (MMP9), membrane-bound intercellular adhesion molecule (mICAM-1) and androgen receptor increased significantly. TNFα also downregulated the steady-state level of occludin, in agreement with earlier results that showed TNFα to disrupt Sertoli cell barrier/BTB function. In addition, TNFα affected the filamentous actin cytoskeleton in Sertoli cells, which appeared to be mediated by cortactin, a regulator of actin dynamics. Taken collectively, these findings imply that germ cells may be involved in BTB restructuring via the localized production of TNFα. These results also illustrate that barrier restructuring correlated with an increase in Sertoli cell mICAM-1, suggesting that it may be critical for adhesion as germ cells traverse the “opened” BTB.
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Affiliation(s)
- Marta Lydka
- Center for Biomedical Research; Population Council; New York, NY USA
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Xiao X, Wong EWP, Lie PPY, Mruk DD, Wong CKC, Cheng CY. Cytokines, polarity proteins, and endosomal protein trafficking and signaling-the sertoli cell blood-testis barrier system in vitro as a study model. Methods Enzymol 2014; 534:181-94. [PMID: 24359954 DOI: 10.1016/b978-0-12-397926-1.00010-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Endosomal signaling is emerging as one of the most important cellular events that regulate signaling function in mammalian cells or an epithelium in response to changes in environment such as the presence of stimuli mediated by cytokines, toxicants, heat, ions during growth and development, and other cellular processes such as cytokinesis and spermatogenesis. Recent studies have shown that protein endocytosis-the initial step of endosomal signaling-involves the participation of polarity proteins, such as partitioning defective protein 6 (Par6), Cdc42 and 14-3-3 (also known as Par5), which in turn is regulated by cytokines (e.g., TGF-β2, TGF-β3) and testosterone at the Sertoli cell blood-testis barrier (BTB) in the mammalian testis. In this short method paper, we provide a detailed protocol of assessing protein endocytosis, the initial and also the most critical step of endosomal signaling at the Sertoli cell BTB. This biochemical endocytosis assay summarizes our experience for the last decade, which should likely be performed in conjunction with the dual-labeled immunofluorescence analysis to assess protein endocytosis. While we are using a Sertoli cell in vitro system that mimics the BTB in vivo, this approach should be applicable to virtually all mammalian cells.
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Affiliation(s)
- Xiang Xiao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA; Department of Reproductive Physiology, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, China
| | - Elissa W P Wong
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Pearl P Y Lie
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Dolores D Mruk
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Chris K C Wong
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA.
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Ricci G, Catizone A. Pleiotropic Activities of HGF/c-Met System in Testicular Physiology: Paracrine and Endocrine Implications. Front Endocrinol (Lausanne) 2014; 5:38. [PMID: 24772104 PMCID: PMC3982073 DOI: 10.3389/fendo.2014.00038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 03/14/2014] [Indexed: 01/28/2023] Open
Abstract
In the last decades, a growing body of evidence has been reported concerning the expression and functional role of hepatocyte growth factor (HGF) on different aspects of testicular physiology. This review has the aim to summarize what is currently known regarding this topic. From early embryonic development to adult age, HGF and its receptor c-Met appeared to be clearly detectable in the testis. These molecules acquire different distribution patterns and roles depending on the developmental stage or the post-natal age considered. HGF acts as a paracrine modulator of testicular functions promoting the epithelium-mesenchyme cross-talk as described even in other organs. Interestingly, it has been reported that testicular HGF acts even as an autocrine factor and that its receptor might be modulated by endocrine signals that change at puberty: HGF receptor expressed by Sertoli cells, in fact, is up-regulated by FSH administration. HGF is in turn able to modify endocrine state of the organism being able to increase testosterone secretion of both fetal and adult Leydig cells. Moreover, c-Met is expressed in mitotic and meiotic male germ cells as well as in spermatozoa. The distribution pattern of c-Met on sperm cell membrane changes in the caput and cauda epididymal sperms and HGF is able to maintain epididymal sperm motility in vitro suggesting a physiological role of this growth factor in the acquisition of sperm motility. Noteworthy changes in HGF concentration in seminal plasma have been reported in different andrological diseases. All together these data indicate that HGF has a role in the control of spermatogenesis and sperm quality either directly, acting on male germ cells, or indirectly acting on tubular and interstitial somatic cells of the testis.
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Affiliation(s)
- Giulia Ricci
- Department of Experimental Medicine, School of Medicine, Second University of Naples, Naples, Italy
| | - Angela Catizone
- Department of Anatomy Histology, Forensic Medicine and Orthopedics, School of Medicine, “Sapienza” University of Rome, Rome, Italy
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Li MWM, Cheng CY, Mruk DD. Sertolin mediates blood-testis barrier restructuring. Endocrinology 2014; 155:1520-31. [PMID: 24467744 PMCID: PMC3959606 DOI: 10.1210/en.2013-1850] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 01/14/2014] [Indexed: 01/12/2023]
Abstract
Two important events that occur during mammalian spermatogenesis are the release of elongated spermatids at late stage VIII of the seminiferous epithelial cycle and the restructuring of the blood-testis barrier (BTB) during stages VIII-XI. Still, it is not completely understood how these cellular events are accomplished within the seminiferous epithelium. In the present study, we investigate how sertolin, a protein that was initially identified, cloned, and partially characterized by our laboratory, functions in these critical events. Sertolin was found at the BTB, as well as at the apical ectoplasmic specialization and apical tubulobulbar complex, where it colocalized with epidermal growth factor receptor kinase substrate 8 and actin-related protein 3, two actin-regulatory proteins. Knockdown of sertolin by RNA interference showed Sertoli cell barrier function to be enhanced when assessed by transepithelial electrical resistance measurements and immunolocalization experiments. By contrast, the integrity of the BTB was disrupted when sertolin was overexpressed in vitro and in vivo. Sertolin overexpression also prompted germ cell loss from the seminiferous epithelium. Taken collectively, these results suggest that sertolin may be involved in coordinating spermatid release and BTB restructuring during spermatogenesis in the rat.
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Affiliation(s)
- Michelle W M Li
- Center for Biomedical Research, Population Council, New York, New York 10065
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Interleukin-6 disrupts blood-testis barrier through inhibiting protein degradation or activating phosphorylated ERK in Sertoli cells. Sci Rep 2014; 4:4260. [PMID: 24584780 PMCID: PMC3939460 DOI: 10.1038/srep04260] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 02/14/2014] [Indexed: 11/09/2022] Open
Abstract
It has been recently ascribed to several inflammatory cytokines (i.e. TGF-β3, TNF-α, and IL-1) a functional role in regulating Sertoli cell blood-testis barrier (BTB) dynamics. In the testis, IL-6 inhibits meiotic DNA synthesis during the seminiferous epithelium cycle, reduces sperm motility and influences the secretion of transferrin and inhibin B by Sertoli cells. Also, it has been shown that IL-6 affects tight junction permeability in Sertoli cells, but, little is known about its role in regulating the BTB. The aim of this study was to investigate the molecular mechanisms by which IL-6 affects BTB dynamics. We show that IL-6 perturbs the integrity of the BTB, and alters the normal localization and steady-state levels of BTB integral membrane proteins. We demonstrated that IL-6 regulates the BTB by inhibiting the degradation of BTB constitutive proteins and activating ERK-MAPK pathways. Our results provide mechanistic insight into the roles of IL-6 in regulating BTB dynamics.
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Liu X, Nie S, Huang D, Xie M. Effects of nonylphenol exposure on expression of cell receptors and secretory function in mouse Sertoli TM4 cells. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2014; 37:608-616. [PMID: 24583408 DOI: 10.1016/j.etap.2014.01.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 01/17/2014] [Accepted: 01/24/2014] [Indexed: 06/03/2023]
Abstract
The aim of this study was to investigate the effects of nonylphenol (NP) exposure on the expression of cell receptors and secretory function in mouse Sertoli TM4 cells. There were no significant changes in mRNA expression of estrogen receptor (ER)-α and toll like receptor (TLR)-4 in the cells exposed to NP for 24h. However, the mRNA expression levels of ER-β, progesterone receptor (PR) and androgen receptor (AR) were down-regulated in NP groups. Furthermore, NP treatment evoked significant changes in protein expression levels of ER-β and follicle-stimulating hormone receptor (FSHR). There were significant changes in the mRNA expression levels of vinculin, N-cadherin and occludin, but not vimentin. Levels of inhibin B, androgen binding protein (ABP) and transferrin (Trf) were found to change significantly in NP challenged cells. Additionally, the decrease of nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) mRNA expression and increase of cytokine levels were simultaneously found in NP stimulated TM4 cells. In conclusion, these findings have shown that NP exposure affected expression of cell receptors and may damage specific secretory function of Sertoli TM4 cells, which may be associated with the male-specific reproductive toxicity of NP.
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Affiliation(s)
- Xiaozhen Liu
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China
| | - Shaoping Nie
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China
| | - Danfei Huang
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China
| | - Mingyong Xie
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
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Lie PPY, Cheng CY, Mruk DD. Signalling pathways regulating the blood-testis barrier. Int J Biochem Cell Biol 2013; 45:621-5. [PMID: 23262290 PMCID: PMC3632505 DOI: 10.1016/j.biocel.2012.12.009] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Revised: 12/02/2012] [Accepted: 12/07/2012] [Indexed: 12/25/2022]
Abstract
Throughout mammalian spermatogenesis, preleptotene/leptotene spermatocytes traverse the blood-testis barrier during stages VIII-XI of the seminiferous epithelial cycle while trapped within a dynamic intermediate compartment that is sealed at north and south poles by tight junctions, basal ectoplasmic specializations, desmosomes and gap junctions. In order for spermatocytes to gain entry into the adluminal compartment of the seminiferous epithelium for continued development, 'old' junctions present above migrating spermatocytes disassemble, while 'new' junctions assemble simultaneously below these germ cells. In this way, the integrity of the blood-testis barrier and the homeostasis of the seminiferous epithelium can remain intact during spermatogenesis. Previous studies have shown an array of cellular events, including protein internalization and cytoskeletal remodeling, to underline blood-testis barrier restructuring, whereas other studies have reported BTB dysfunction to associate with activation of the p38 mitogen-activated protein kinase pathway. Herein, we discuss the signaling pathways and mechanisms involved in blood-testis barrier restructuring in the mammalian testis.
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Affiliation(s)
- Pearl P. Y. Lie
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065
| | - C. Yan Cheng
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065
| | - Dolores D. Mruk
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065
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Su W, Mruk DD, Cheng CY. Regulation of actin dynamics and protein trafficking during spermatogenesis--insights into a complex process. Crit Rev Biochem Mol Biol 2013; 48:153-72. [PMID: 23339542 DOI: 10.3109/10409238.2012.758084] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In the mammalian testis, extensive restructuring takes place across the seminiferous epithelium at the Sertoli-Sertoli and Sertoli-germ cell interface during the epithelial cycle of spermatogenesis, which is important to facilitate changes in the cell shape and morphology of developing germ cells. However, precise communications also take place at the cell junctions to coordinate the discrete events pertinent to spermatogenesis, namely spermatogonial renewal via mitosis, cell cycle progression and meiosis, spermiogenesis and spermiation. It is obvious that these cellular events are intimately related to the underlying actin-based cytoskeleton which is being used by different cell junctions for their attachment. However, little is known on the biology and regulation of this cytoskeleton, in particular its possible involvement in endocytic vesicle-mediated trafficking during spermatogenesis, which in turn affects cell adhesive function and communication at the cell-cell interface. Studies in other epithelia in recent years have shed insightful information on the intimate involvement of actin dynamics and protein trafficking in regulating cell adhesion and communications. The goal of this critical review is to provide an updated assessment of the latest findings in the field on how these complex processes are being regulated during spermatogenesis. We also provide a working model based on the latest findings in the field including our laboratory to provide our thoughts on an apparent complicated subject, which also serves as the framework for investigators in the field. It is obvious that this model will be rapidly updated when more data are available in future years.
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Affiliation(s)
- Wenhui Su
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY 10065, USA
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Xiao X, Mruk DD, Cheng CY. c-Yes regulates cell adhesion at the apical ectoplasmic specialization-blood-testis barrier axis via its effects on protein recruitment and distribution. Am J Physiol Endocrinol Metab 2013; 304:E145-59. [PMID: 23169788 PMCID: PMC3543571 DOI: 10.1152/ajpendo.00422.2012] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
During spermatogenesis, extensive restructuring takes place at the cell-cell interface since developing germ cells migrate progressively from the basal to the adluminal compartment of the seminiferous epithelium. Since germ cells per se are not motile cells, their movement relies almost exclusively on the Sertoli cell. Nonetheless, extensive exchanges in signaling take place between these cells in the seminiferous epithelium. c-Yes, a nonreceptor protein tyrosine kinase belonging to the Src family kinases (SFKs) and a crucial signaling protein, was recently shown to be upregulated at the Sertoli cell-cell interface at the blood-testis barrier (BTB) at stages VIII-IX of the seminiferous epithelial cycle of spermatogenesis. It was also highly expressed at the Sertoli cell-spermatid interface known as apical ectoplasmic specialization (apical ES) at stage V to early stage VIII of the epithelial cycle during spermiogenesis. Herein, it was shown that the knockdown of c-Yes by RNAi in vitro and in vivo affected both Sertoli cell adhesion at the BTB and spermatid adhesion at the apical ES, causing a disruption of the Sertoli cell tight junction-permeability barrier function, germ cell loss from the seminiferous epithelium, and also a loss of spermatid polarity. These effects were shown to be mediated by changes in distribution and/or localization of adhesion proteins at the BTB (e.g., occludin, N-cadherin) and at the apical ES (e.g., nectin-3) and possibly the result of changes in the underlying actin filaments at the BTB and the apical ES. These findings implicate that c-Yes is a likely target of male contraceptive research.
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Affiliation(s)
- Xiang Xiao
- Center for Biomedical Research, Population Council, New York, NY 10065, USA
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Mok KW, Mruk DD, Lee WM, Cheng CY. Rictor/mTORC2 regulates blood-testis barrier dynamics via its effects on gap junction communications and actin filament network. FASEB J 2013; 27:1137-52. [PMID: 23288930 DOI: 10.1096/fj.12-212977] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In the mammalian testis, coexisting tight junctions (TJs), basal ectoplasmic specializations, and gap junctions (GJs), together with desmosomes near the basement membrane, constitute the blood-testis barrier (BTB). The most notable feature of the BTB, however, is the extensive network of actin filament bundles, which makes it one of the tightest blood-tissue barriers. The BTB undergoes restructuring to facilitate the transit of preleptotene spermatocytes at stage VIII-IX of the epithelial cycle. Thus, the F-actin network at the BTB undergoes cyclic reorganization via a yet-to-be explored mechanism. Rictor, the key component of mTORC2 that is known to regulate actin cytoskeleton, was shown to express stage-specifically at the BTB in the seminiferous epithelium. Its expression was down-regulated at the BTB in stage VIII-IX tubules, coinciding with BTB restructuring at these stages. Using an in vivo model, a down-regulation of rictor at the BTB was also detected during adjudin-induced BTB disruption, illustrating rictor expression is positively correlated with the status of the BTB integrity. Indeed, the knockdown of rictor by RNAi was found to perturb the Sertoli cell TJ-barrier function in vitro and the BTB integrity in vivo. This loss of barrier function was accompanied by changes in F-actin organization at the Sertoli cell BTB in vitro and in vivo, associated with a loss of interaction between actin and α-catenin or ZO-1. Rictor knockdown by RNAi was also found to impede Sertoli cell-cell GJ communication, disrupting protein distribution (e.g., occludin, ZO-1) at the BTB, illustrating that rictor is a crucial BTB regulator.
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Affiliation(s)
- Ka-Wai Mok
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, NY 10065, USA
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Mok KW, Mruk DD, Silvestrini B, Cheng CY. rpS6 Regulates blood-testis barrier dynamics by affecting F-actin organization and protein recruitment. Endocrinology 2012; 153:5036-48. [PMID: 22948214 PMCID: PMC3512016 DOI: 10.1210/en.2012-1665] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
During spermatogenesis, preleptotene spermatocytes residing near the basement membrane of the seminiferous tubule must traverse the blood-testis barrier (BTB) at stage VIII-IX of the epithelial cycle to continue their development in the adluminal compartment. Unlike other blood-tissue barriers (e.g. the blood-brain barrier) that are created by the endothelial tight junction (TJ) barrier of capillaries, the BTB is created by specialized junctions between Sertoli cells in which TJ coexists with basal ectoplasmic specialization (basal ES, a testis-specific adherens junction). The basal ES is typified by the presence of tightly packed actin filament bundles sandwiched between cisternae of endoplasmic reticulum and the apposing plasma membranes of Sertoli cells. These actin filament bundles also confer unusual adhesive strength to the BTB. Yet the mechanisms by which these filamentous actin (F-actin) networks are regulated from the bundled to the debundled state to facilitate the transit of spermatocytes remain elusive. Herein, we provide evidence that ribosomal protein S6 (rpS6), the downstream signaling molecule of the mammalian target of rapamycin complex 1 (mTORC1) pathway, is a major regulator of F-actin organization and adhesion protein recruitment at the BTB. rpS6 is restrictively and spatiotemporally activated at the BTB during the epithelial cycle. An activation of rpS6 led to a disruption of the Sertoli cell TJ barrier and BTB integrity. Its silencing in vitro or in vivo by using small interfering RNA duplexes or short hairpin RNA was found to promote the Sertoli cell TJ permeability barrier by the recruitment of adhesion proteins (e.g. claudin-11 and occludin) to the BTB. Thus, rpS6 in the mTORC1 pathway regulates BTB restructuring via its effects on the F-actin organization and protein recruitment at the BTB.
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Affiliation(s)
- Ka-Wai Mok
- Center for Biomedical Research, Population Council, New York, New York 10065, USA
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Xiao X, Cheng CY, Mruk DD. Intercellular adhesion molecule-1 is a regulator of blood-testis barrier function. J Cell Sci 2012; 125:5677-89. [PMID: 22976294 DOI: 10.1242/jcs.107987] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The mechanism underlying the movement of preleptotene/leptotene spermatocytes across the blood-testis barrier (BTB) during spermatogenesis is not well understood largely owing to the fact that the BTB, unlike most other blood-tissue barriers, is composed of several co-existing and co-functioning junction types. In the present study, we show that intercellular adhesion molecule-1 [ICAM-1, a Sertoli and germ cell adhesion protein having five immunoglobulin (Ig)-like domains, in addition to transmembrane and cytoplasmic domains] is a regulator of BTB integrity. Initial experiments showed ICAM-1 to co-immunoprecipitate and co-localize with tight junction and basal ectoplasmic specialization proteins such as occludin and N-cadherin, which contribute to BTB function. More importantly, overexpression of ICAM-1 in Sertoli cells in vitro enhanced barrier function when monitored by transepithelial electrical resistance measurements, illustrating that ICAM-1-mediated adhesion can promote BTB integrity. On the other hand, overexpression of a truncated form of ICAM-1 that consisted only of the five Ig-like domains (sICAM-1; this form of ICAM-1 is known to be secreted) elicited an opposite effect when Sertoli cell barrier function was found to be perturbed in vitro; in this case, sICAM-1 overexpression resulted in the downregulation of several BTB constituent proteins, which was probably mediated by Pyk2/p-Pyk2-Y402 and c-Src/p-Src-Y530. These findings were expanded to the in vivo level when BTB function was found to be disrupted following sICAM-1 overexpression. These data illustrate the existence of a unique mechanism in the mammalian testis where ICAM-1 can either positively or negatively regulate BTB function.
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Affiliation(s)
- Xiang Xiao
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, USA
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Tu LH, Yu LL, Xiong CL, Zhang HP. Potential role of prokineticin 2 in experimental varicocele-induced rat testes. Urology 2012; 80:952.e15-9. [PMID: 22840859 DOI: 10.1016/j.urology.2012.05.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2012] [Revised: 04/26/2012] [Accepted: 05/23/2012] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine the possible role of prokineticin 2 in varicocele by inducing varicoceles in adult rats. METHODS Forty male Sprague-Dawley rats were used for sham operation (n = 10) and varicocele (n = 30) groups. Experimental varicocele was induced by partial ligation of the left renal vein in the varicocele, whereas the sham operation group only received a sham induction of varicocele. Left testes were harvested for real-time quantitative polymerase chair readtion analysis 2, 4, and 8 weeks after the induction of varicocele. RESULTS The expression of prokineticin 2 mRNA in 8-week varicocele-induced rats was significantly higher (P < .05) than that in the sham operation group. CONCLUSION The present study suggests that prokineticin 2 expression is increased by varicocele induction and it may have a role in varicocele-induced infertility.
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Affiliation(s)
- Li-Hui Tu
- Institute of Family Planning Research, Center of Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Chen J, Fok KL, Chen H, Zhang XH, Xu WM, Chan HC. Cryptorchidism-induced CFTR down-regulation results in disruption of testicular tight junctions through up-regulation of NF-κB/COX-2/PGE2. Hum Reprod 2012; 27:2585-97. [PMID: 22777528 DOI: 10.1093/humrep/des254] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
STUDY QUESTION Does elevated temperature-induced cystic fibrosis transmembrane conductance regulator (CFTR) down-regulation in Sertoli cells in cryptorchid testis disrupt testicular tight junctions (TJs) through the nuclear factor kappa B (NF-κB)/cyclooxygenase-2 (COX-2)/prostaglandin E(2) (PGE(2)) pathway? SUMMARY ANSWER Our results suggest that CFTR may be involved in regulating testicular TJs and the blood-testis barrier (BTB) through its negative regulation of the NF-κB/COX-2/PGE(2) pathway in Sertoli cells, a defect of which may result in the spermatogenesis defect in cryptorchidism. WHAT IS KNOWN ALREADY Cryptorchidism, or undescended testes, is known to result in defective spermatogenesis. Although an elevated testicular temperature is regarded as an important factor affecting spermatogenesis in cryptorchidism, the exact mechanism remains elusive. It is known that the expression of functional CFTR is temperature sensitive. Our previous study has demonstrated that CFTR negatively regulates NF-κB/COX-2/PGE(2) in bronchial epithelial cells. Disruption of TJs by COX-2/PGE(2) has been found in tumour cells. STUDY DESIGN AND METHODS Expression of CFTR, NF-κB, COX-2 and TJ proteins was examined in the testes of a surgical-induced cryptorchidism mouse model and a testicular hyperthermia mouse model, as well as in control or CFTR-inhibited/knocked down primary rat Sertoli cells. PGE(2) production was measured by ELISA. Sertoli cell barrier function was determined by transepethelial resistance (TER) measurements in rat Sertoli cell primary cultures. BTB integrity in the cryptorchidism model was monitored by examining tracker dye injected into seminiferous tubules. MAIN RESULTS Down-regulation of CFTR accompanied by activation of NF-κB, up-regulation of COX-2 and down-regulation of TJ proteins, including ZO-1 and occludin, was observed in a cryptorchidism mouse model. BTB leakage revealed impaired BTB integrity in cryptorchid testes, confirming the destruction of TJs. The inverse correlation of CFTR and COX-2 was further confirmed in a mouse testis hyperthermia model and CFTR knockout mouse model. Culturing primary Sertoli cells at 37°C, which mimics the pathological condition of cryptorchidism, led to a significant decrease in CFTR and increase in COX-2 expression and PGE(2) production compared with the culture at the physiological 32°C. Inhibition or knockdown of CFTR led to increased COX-2 but decreased ZO-1 and occludin expression in Sertoli cells, which could be mimicked by PGE(2), but reversed by NF-κB or COX-2 inhibitor, suggesting that the regulation of TJs by CFTR is mediated by a NF-κB/COX-2/PGE(2) pathway. Inhibition of CFTR or administration of PGE(2) significantly decreased Sertoli cell TER. LIMITATIONS This study has tested only the CFTR/NF-κB/COX-2/PGE(2) pathway in mouse testes in vivo and in rat Sertoli cells in vitro, and thus, it has some limitations. Further investigations in other species, especially humans, are needed. WIDER IMPLICATIONS OF THE FINDINGS Our study may shed more light on one of the aspects of the complicated underlying mechanisms of defective spermatogenesis induced by cryptorchidism.
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Affiliation(s)
- Jing Chen
- Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, NT, Hong Kong
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40
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Lie PPY, Cheng CY, Mruk DD. The biology of interleukin-1: emerging concepts in the regulation of the actin cytoskeleton and cell junction dynamics. Cell Mol Life Sci 2012; 69:487-500. [PMID: 21744066 PMCID: PMC3297025 DOI: 10.1007/s00018-011-0760-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 06/14/2011] [Accepted: 06/17/2011] [Indexed: 01/28/2023]
Abstract
Interleukin (IL)-1 is a proinflammatory cytokine with important roles in innate immunity, as well as in normal tissue homeostasis. Interestingly, recent studies have also shown IL-1 to function in the dynamics of the actin cytoskeleton and cell junctions. For example, treatment of different epithelia with IL-1α often results in the restructuring of the actin network and cell junctions, thereby leading to junction disassembly. In this review, we highlight new and interesting findings that show IL-1 to be a critical player of restructuring events in the seminiferous epithelium of the testis during spermatogenesis.
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Affiliation(s)
- Pearl P. Y. Lie
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065 USA
| | - C. Yan Cheng
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065 USA
| | - Dolores D. Mruk
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065 USA
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Catizone A, Ricci G, Caruso M, Ferranti F, Canipari R, Galdieri M. Hepatocyte growth factor (HGF) regulates blood-testis barrier (BTB) in adult rats. Mol Cell Endocrinol 2012; 348:135-46. [PMID: 21843593 DOI: 10.1016/j.mce.2011.07.050] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 07/29/2011] [Accepted: 07/29/2011] [Indexed: 01/26/2023]
Abstract
We have studied the effects of HGF on BTB dynamics in adult rats. We demonstrate that, at stages VII-VIII of the epithelium wave when germ cells traverse the BTB, HGF reduces the levels of occludin and influences its distribution pattern and assembling. Moreover, we report that, at stages VII-VIII, HGF significantly increases the amount of active TGF-β and the amount of uPA present in the tubules. For the first time we report that, in the same stages, HGF reduces the amount of actin present in the BTB region, in which occludin levels are highest, and modifies the morphology of the actin cytoskeleton network. At the level of maximal intensity of occludin fluorescence, we report that HGF also modifies the colocalization of occludin and actin. Lastly, we demonstrate that HGF is maximally expressed at stages VII-VIII, whereas its levels fall in the subsequent stages.
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Affiliation(s)
- A Catizone
- Dept. of Anatomy, Histology, Forensic Medicine and Orthopedics, Section of Histology and Embryology, School of Pharmacy and Medicine, Sapienza University of Rome, Rome, Italy
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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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Mok KW, Mruk DD, Lee WM, Cheng CY. A study to assess the assembly of a functional blood-testis barrier in developing rat testes. SPERMATOGENESIS 2011; 1:270-280. [PMID: 22319674 PMCID: PMC3271668 DOI: 10.4161/spmg.1.3.17998] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 08/09/2011] [Indexed: 01/08/2023]
Abstract
The blood-testis barrier (BTB) is an important ultrastructure in the seminiferous tubule of the mammalian testis that segregates the events of spermatogenesis, in particular post-meiotic germ cell development, from the harmful substances in the environment including toxicants and drugs, as well as from the unwanted hormones and biomolecules in the systemic circulation. It is known that the BTB is assembled by ∼15-21 days postpartum (dpp) in rats coinciding with the onset of late cell cycle progression, namely the formation of zygotene and pachytene spermatocytes by day 15-18 dpp. This is to prepare for: (1) the differentiation/transformation of pachytene spermatocytes to diplotene and dictyate spermatocytes and (2) meiosis I and II, which take place by 23-26 and 26 dpp, respectively. Recent findings have shown spermatogonia/spermatogonial stem cells (SSC) in the tubules failed to re-initiate spermatogenesis by differentiating spermatogonia beyond type A spermatogonia in the absence of a functional BTB, leading to meiotic arrest. These studies thus illustrate that a functional BTB is crucial to the initiation and/or re-initiation of spermatogenesis. Herein, we sought to examine the precise time window when a functional and intact BTB is established in the developing rat testis during the final stage of cell cycle progression and meiosis. Using the techniques of: (1) dual-labeled immunofluorescence analysis to assess the distribution of integrated proteins at the tight junction (TJ), basal ectoplasmic specialization [basal ES, a testis-specific atypical adherens junction (AJ) type] and gap junction (GJ) at the BTB, (2) functional assay to assess the BTB integrity in vivo, (3) immunoblot analysis to monitor changes in steady-state levels of adhesion proteins at the BTB, and (4) co-immunoprecipitation to assess changes in protein-protein interactions at the BTB, it was shown that a BTB was being assembled by day 15-20 dpp, but a functional BTB was not fully established until day 25 dpp in Sprague-Dawley rats, tightly associated with the onset of meiosis I and II. These findings thus illustrate the significance of the BTB on cell cycle progression and the preparation for meiosis, such as germ cell differentiation beyond type A spermatogonia.
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Affiliation(s)
- Ka-Wai Mok
- Center for Biomedical Research; The Population Council; New York, NY USA
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Cheng CY, Wong EW, Lie PP, Li MW, Mruk DD, Yan HH, Mok KW, Mannu J, Mathur PP, Lui WY, Lee WM, Bonanomi M, Silvestrini B. Regulation of blood-testis barrier dynamics by desmosome, gap junction, hemidesmosome and polarity proteins: An unexpected turn of events. SPERMATOGENESIS 2011; 1:105-115. [PMID: 22319658 PMCID: PMC3271652 DOI: 10.4161/spmg.1.2.15745] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2010] [Revised: 04/04/2011] [Accepted: 04/05/2011] [Indexed: 01/11/2023]
Abstract
The blood-testis barrier (BTB) is a unique ultrastructure in the mammalian testis. Unlike other blood-tissue barriers, such as the blood-brain barrier and the blood-ocular (or blood-retina) barrier which formed by tight junctions (TJ) between endothelial cells of the microvessels, the BTB is constituted by coexisting TJ, basal ectoplasmic specialization (basal ES), desmosomes and gap junctions between adjacent Sertoli cells near the basement membrane of the seminiferous tubule. The BTB also divides the seminiferous epithelium into the apical (or adluminal) and basal compartments so that meiosis I and II and post-meiotic germ cell development can all take place in a specialized microenvironment in the apical compartment behind the BTB. While the unusual anatomical features of the BTB have been known for decades, the physiological function of the coexisting junctions, in particular the desmosome and gap junction, that constitute the BTB was unknown until recently. Based on recently published findings, we critically evaluate the role of the desmosome and gap junction that serve as a signaling platform to coordinate the "opening" and "closing" of the TJ-permeability barrier conferred by TJ and basal ES during the seminiferous epithelial cycle of spermatogenesis. This is made possible by polarity proteins working in concert with nonreceptor protein tyrosine kinases, such as focal adhesion kinase (FAK) and c-Src, at the site to regulate endosome-mediated protein trafficking events (e.g., endocytosis, transcytosis, recycling or protein degradation). These events not only serve to destabilize the existing "old" BTB above preleptotene spermatocytes in transit in "clones" at the BTB, but also contribute to the assembly of "new" BTB below the transiting spermatocytes. Furthermore, hemidesmosomes at the Sertoli cell-basement membrane interface also contribute to the BTB restructuring events at stage VIII of the epithelial cycle. Additionally, the findings that a gap junction at the BTB provides a possible route for the passage of toxicants [e.g., bisphenol A (BPA)] and potential male contraceptives (e.g., adjudin) across the BTB also illustrate that these coexisting junctions, while helpful to maintain the immunological barrier integrity during the transit of spermatocytes, can be the "gateway" to making the BTB so vulnerable to toxicants and/or chemicals, causing male reproductive dysfunction.
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Affiliation(s)
- C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; The Population Council; New York, NY USA
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Mruk DD, Cheng CY. Desmosomes in the testis: Moving into an unchartered territory. SPERMATOGENESIS 2011; 1:47-51. [PMID: 21866275 PMCID: PMC3158645 DOI: 10.4161/spmg.1.1.15443] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 03/14/2011] [Indexed: 01/18/2023]
Abstract
Desmosomes are cell-cell junctions that link to cytoplasmic intermediate filaments, and they are known to mediate robust and stable adhesion in organs such as the skin and heart. Desmosomes are also present between apposing Sertoli cells at the blood-testis barrier, and between Sertoli cells and all germ cells up to, but not including, step 8 spermatids in the seminiferous epithelium. Unfortunately, they remain to be one of the least studied cell junction types in the seminiferous epithelium of the mammalian testis. In this article, we briefly discuss how kinases and the actin cytoskeleton relate to the study of desmosomes in the testis. It is hoped that this information is used to initiate more studies on the biology of the desmosome in the future.
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Affiliation(s)
- Dolores D Mruk
- The Population Council; Center for Biomedical Research; New York, NY USA
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