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Wanjari UR, Gopalakrishnan AV. Blood-testis barrier: a review on regulators in maintaining cell junction integrity between Sertoli cells. Cell Tissue Res 2024; 396:157-175. [PMID: 38564020 DOI: 10.1007/s00441-024-03894-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 03/20/2024] [Indexed: 04/04/2024]
Abstract
The blood-testis barrier (BTB) is formed adjacent to the seminiferous basement membrane. It is a distinct ultrastructure, partitioning testicular seminiferous epithelium into apical (adluminal) and basal compartments. It plays a vital role in developing and maturing spermatocytes into spermatozoa via reorganizing its structure. This enables the transportation of preleptotene spermatocytes across the BTB, from basal to adluminal compartments in the seminiferous tubules. Several bioactive peptides and biomolecules secreted by testicular cells regulate the BTB function and support spermatogenesis. These peptides activate various downstream signaling proteins and can also be the target themself, which could improve the diffusion of drugs across the BTB. The gap junction (GJ) and its coexisting junctions at the BTB maintain the immunological barrier integrity and can be the "gateway" during spermatocyte transition. These junctions are the possible route for toxicant entry, causing male reproductive dysfunction. Herein, we summarize the detailed mechanism of all the regulators playing an essential role in the maintenance of the BTB, which will help researchers to understand and find targets for drug delivery inside the testis.
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Affiliation(s)
- Uddesh Ramesh Wanjari
- Department of Biomedical Sciences, School of Bio-Sciences and Technology, Vellore Institute of Technology, Tamil Nadu, Vellore, PIN 632014, India
| | - Abilash Valsala Gopalakrishnan
- Department of Biomedical Sciences, School of Bio-Sciences and Technology, Vellore Institute of Technology, Tamil Nadu, Vellore, PIN 632014, India.
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Chen N, Wan X, Wang M, Li Y, Wang X, Zeng L, Zhou J, Zhang Y, Cheng S, Shen Y. Cross-talk between Vimentin and autophagy regulates blood-testis barrier disruption induced by cadmium. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 346:123625. [PMID: 38401636 DOI: 10.1016/j.envpol.2024.123625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/06/2024] [Accepted: 02/20/2024] [Indexed: 02/26/2024]
Abstract
The blood-testis barrier (BTB) plays a vital role in mammalian spermatogenesis by separating the seminiferous epithelium into an adluminal and a basal compartment. Cadmium (Cd) is a toxic heavy metal that is widely present in the environment. We observed that Cd can induce BTB disruption, leading to apoptosis of testicular cells. However, the molecular mechanisms contributing to BTB injury induced by Cd have not yet been fully clarified. Vimentin (Vim) is an important desmosome-like junction protein that mediates robust adhesion in the BTB. In this study, we investigated how Vim responds to Cd. We found that Cd treatment led to a significant decrease in Vim expression, accompanied by a marked increase in LC3-II expression and a higer number of autophagosomes. Interestingly, we also observed that Cd-induced autophagy was associated with decreased Vim activity and enhanced apoptosis of testicular cells. To further investigate the role of autophagy in Vim regulation under Cd exposure, we treated cells with an autophagy inhibitor called 3-MA. We found that 3-MA treatment enhanced Vim expression and improved the disruption of the BTB under Cd exposure. Additionally, the inhibition of Vim confirmed the role of autophagy in modulating Vim expression. These results reveal a previously unknown regulatory mechanism of Cd involving the interplay between a heavy metal and a protein.
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Affiliation(s)
- Na Chen
- Department of Obstetrics and Gynecology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, PR China
| | - Xiaoyan Wan
- Department of Obstetrics and Gynecology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510620, PR China
| | - Mei Wang
- Center for Reproductive Medicine, Zhongnan Hospital of Wuhan University, Wuhan, 430071, Hubei, PR China
| | - Yamin Li
- Department of Woman's Health Care, Maternal and Child Health Hospital of Hubei Province, Wuhan, 430071, Hubei, PR China
| | - Xiaofei Wang
- Center for Reproductive Medicine, Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, Yichang, 443000, Hubei, PR China
| | - Ling Zeng
- Medical Genetics Center, Maternal and Child Health Hospital of Hubei Province, Wuhan, 430070, PR China
| | - Jinzhao Zhou
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, PR China
| | - Yanwei Zhang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, PR China
| | - Shun Cheng
- College of Zhixing, Hubei University, Wuhan, 430011, PR China
| | - Yi Shen
- Department of Obstetrics and Gynecology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, PR China.
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Zhao Z, Cai Y, Lin X, Liu N, Qin Y, Wu Y. The Role of Heat-Induced Stress Granules in the Blood-Testis Barrier of Mice. Int J Mol Sci 2024; 25:3637. [PMID: 38612449 PMCID: PMC11011666 DOI: 10.3390/ijms25073637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 03/15/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024] Open
Abstract
Stress granules (SGs) are membraneless ribonucleoprotein (RNP)-based cellular foci formed in response to stress, facilitating cell survival by protecting against damage. Mammalian spermatogenesis should be maintained below body temperature for proper development, indicating its vulnerability to heat stress (HS). In this study, biotin tracer permeability assays showed that the inhibition of heat-induced SG assembly in the testis by 4-8 mg/kg cycloheximide significantly increased the percentage of seminiferous tubules with a damaged blood-testis barrier (BTB). Western blot results additionally revealed that the suppression of heat-induced SG assembly in Sertoli cell line, TM4 cells, by RNA inference of G3bp1/2 aggravated the decline in the BTB-related proteins ZO-1, β-Catenin and Claudin-11, indicating that SGs could protect the BTB against damage caused by HS. The protein components that associate with SGs in Sertoli cells were isolated by sequential centrifugation and immunoprecipitation, and were identified by liquid chromatography with tandem mass spectrometry. Gene Ontology and KEGG pathway enrichment analysis revealed that their corresponding genes were mainly involved in pathways related to proteasomes, nucleotide excision repair, mismatch repair, and DNA replication. Furthermore, a new SG component, the ubiquitin associated protein 2 (UBAP2), was found to translocate to SGs upon HS in TM4 cells by immunofluorescence. Moreover, SG assembly was significantly diminished after UBAP2 knockdown by RNA inference during HS, suggesting the important role of UBAP2 in SG assembly. In addition, UBAP2 knockdown reduced the expression of ZO-1, β-Catenin and Claudin-11, which implied its potential role in the function of the BTB. Overall, our study demonstrated the role of SGs in maintaining BTB functions during HS and identified a new component implicated in SG formation in Sertoli cells. These findings not only offer novel insights into the biological functions of SGs and the molecular mechanism of low fertility in males in summer, but also potentially provide an experimental basis for male fertility therapies.
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Affiliation(s)
- Zhifeng Zhao
- College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Yuqing Cai
- College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Xinyi Lin
- College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Ning Liu
- College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
- State Key Laboratory of Animal Nutrition and Feeding, China Agricultural University, Beijing 100193, China
- National Engineering Laboratory for Animal Breeding, China Agricultural University, Beijing 100193, China
| | - Yinghe Qin
- College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
- State Key Laboratory of Animal Nutrition and Feeding, China Agricultural University, Beijing 100193, China
- National Engineering Laboratory for Animal Breeding, China Agricultural University, Beijing 100193, China
| | - Yingjie Wu
- College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
- State Key Laboratory of Animal Nutrition and Feeding, China Agricultural University, Beijing 100193, China
- National Engineering Laboratory for Animal Breeding, China Agricultural University, Beijing 100193, China
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Tang EI, Cheng CY. MARK2 and MARK4 Regulate Sertoli Cell BTB Dynamics Through Microtubule and Actin Cytoskeletons. Endocrinology 2022; 163:6667645. [PMID: 35971301 PMCID: PMC10147390 DOI: 10.1210/endocr/bqac130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Indexed: 11/19/2022]
Abstract
Microtubule affinity-regulating kinases (MARKs) are nonreceptor Ser/Thr protein kinases known to regulate cell polarity and microtubule dynamics in Caenorhabditis elegans, Drosophila, invertebrates, vertebrates, and mammals. An earlier study has shown that MARK4 is present at the ectoplasmic specialization and blood-testis barrier (BTB) in the seminiferous epithelium of adult rat testes. Here, we report the function of MARK4 and another isoform MARK2 in Sertoli cells at the BTB. Knockdown of MARK2, MARK4, or MARK2 and MARK4 by RNAi using the corresponding siRNA duplexes without apparent off-target effects was shown to impair tight junction (TJ)-permeability barrier at the Sertoli cell BTB. It also disrupted microtubule (MT)- and actin-based cytoskeletal organization within Sertoli cells. Although MARK2 and MARK4 were shown to share sequence homology, they likely regulated the Sertoli cell BTB and MT cytoskeleton differently. Disruption of the TJ-permeability barrier following knockdown of MARK4 was considerably more severe than loss of MARK2, though both perturbed the barrier. Similarly, loss of MARK2 affected MT organization in a different manner than the loss of MARK4. Knockdown of MARK2 caused MT bundles to be arranged around the cell periphery, whereas knockdown of MARK4 caused MTs to retract from the cell edge. These differences in effects on the TJ-permeability barrier are likely from the unique roles of MARK2 and MARK4 in regulating the MT cytoskeleton of the Sertoli cell.
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Affiliation(s)
- Elizabeth I Tang
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, Rockefeller University, New York, NY 10065, USA
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, Rockefeller University, New York, NY 10065, USA
- Department of Urology and Andrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
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Meng Z, Liu Y, Zhou J, Zheng B, Lv J. Drug transport across the blood-testis barrier. Am J Transl Res 2022; 14:6412-6423. [PMID: 36247247 PMCID: PMC9556450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 08/03/2022] [Indexed: 06/16/2023]
Abstract
The blood-testis barrier transfers nutrients to spermatogenic tubules to ensure the normal physiological function of the testes. It also restricts the "entry and exit" of biological macromolecules in the testicular lumen and provides a unique microenvironment for spermatogenesis. This makes the testes a safe place for some viruses and tumors, as immune factors cannot function and drugs fail to reach therapeutic concentrations in the testes. This review aimed to describe the factors regulating the structure and physiological function of the blood-testis barrier. By understanding therapeutic mechanisms of action, drugs can be developed to function in the testicles.
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Affiliation(s)
- Zhixiang Meng
- Suzhou Dushu Lake Hospital (Dushu Lake Hospital Affiliated to Soochow University)Suzhou 215124, China
| | - Yawei Liu
- Suzhou Dushu Lake Hospital (Dushu Lake Hospital Affiliated to Soochow University)Suzhou 215124, China
| | - Jian Zhou
- Suzhou Dushu Lake Hospital (Dushu Lake Hospital Affiliated to Soochow University)Suzhou 215124, China
| | - Bo Zheng
- State Key Laboratory of Reproductive Medicine, Center for Reproduction and Genetics, Suzhou Municipal Hospital, The Affiliated Suzhou Hospital of Nanjing Medical University, Gusu School, Nanjing Medical UniversitySuzhou 215002, China
- State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical UniversityNanjing 211166, China
| | - Jinxing Lv
- Suzhou Dushu Lake Hospital (Dushu Lake Hospital Affiliated to Soochow University)Suzhou 215124, China
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Li J, You Y, Zhang P, Huang X, Dong L, Yang F, Yu X, Chang D. Qiangjing tablets repair of blood-testis barrier dysfunction in rats via regulating oxidative stress and p38 MAPK pathway. BMC Complement Med Ther 2022; 22:133. [PMID: 35568844 PMCID: PMC9107122 DOI: 10.1186/s12906-022-03615-z] [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: 12/18/2021] [Accepted: 05/04/2022] [Indexed: 11/24/2022] Open
Abstract
Background The blood-testis barrier (BTB) is a physical barrier of the testis to prevent various exogenous substrates from entering apical compartments and provides immune privilege for spermatogenesis, which is essential for normal spermatogenic function of testis. It has been shown that oxidative stress can damage BTB by activating the p38 MAPK pathway. In Traditional Chinese Medicine, Qiangjing tablets (QJT) improve spermatogenesis and increase pregnancy rates. Previous studies have confirmed that QJT can improve sperm quality and have obvious antioxidant effects. In this study, we explore whether QJT contributes to recovery from BTB dysfunction in rats. Methods BTB dysfunction was induced in rats by 1% Cyclophosphamide (CP). The CP-induced rats in the treatment group were given a dose of QJT (0.45 g/kg·d) by gavage. Testis tissues were collected for histopathological and biochemical analysis, and the testis weight was estimated. Levels of BTB-related proteins and antioxidant enzyme were analyzed in the testis tissues. Results QJT resolved the pathological injury of rats testis induced by CP. Furthermore, MDA levels were significantly reduced, and the levels of SOD markedly increased in the testicular tissue after QJT treatment. In addition, QJT down-regulated the expression of p38 protein in rat testis and up-regulated the expressions of key proteins ZO-1, occludin and F-actin in BTB. Conclusion These results demonstrate that QJT exerts protective effects on CP-induced rats with BTB dysfunction, likely by regulating the oxidative stress-mediated p38 MAPK pathway. Supplementary Information The online version contains supplementary material available at 10.1186/s12906-022-03615-z.
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Affiliation(s)
- Junjun Li
- TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, The People's Republic of China.,The Reproductive & Women-Children Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, 610041, The People's Republic of China
| | - Yaodong You
- TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, The People's Republic of China
| | - Peihai Zhang
- TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, The People's Republic of China
| | - Xiaopeng Huang
- TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, The People's Republic of China
| | - Liang Dong
- The Reproductive & Women-Children Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, 610041, The People's Republic of China
| | - Fang Yang
- The Reproductive & Women-Children Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, 610041, The People's Republic of China
| | - Xujun Yu
- TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, The People's Republic of China. .,School of Medical and Life Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, The People's Republic of China.
| | - Degui Chang
- TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, The People's Republic of China.
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7
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She J, Feng N, Zheng W, Zheng H, Cai P, Zou H, Yuan Y, Gu J, Liu Z, Bian J. Zearalenone Exposure Disrupts Blood-Testis Barrier Integrity through Excessive Ca 2+-Mediated Autophagy. Toxins (Basel) 2021; 13:toxins13120875. [PMID: 34941713 PMCID: PMC8703826 DOI: 10.3390/toxins13120875] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/30/2021] [Accepted: 12/02/2021] [Indexed: 12/24/2022] Open
Abstract
Zearalenone (ZEA), a common mycotoxin in grains and animal feeds, has been associated with male reproductive disorders. However, the potential toxicity mechanism of ZEA is not fully understood. In this study, in vivo and in vitro models were used to explore the effects of ZEA on the blood-testis barrier (BTB) and related molecular mechanisms. First, male BALB/C mice were administered ZEA orally (40 mg/kg·bw) for 5-7 d. Sperm motility, testicular morphology, and expressions of BTB junction proteins and autophagy-related proteins were evaluated. In addition, TM4 cells (mouse Sertoli cells line) were used to delineate the molecular mechanisms that mediate the effects of ZEA on BTB. Our results demonstrated that ZEA exposure induced severe testicular damage in histomorphology and an ultrastructural, time-dependent decrease in the expression of blood-testis barrier junction-related proteins, accompanied by an increase in the expression of autophagy-related proteins. Additionally, similar to the in vitro results, the dose-dependent treatment of ZEA increased the level of cytoplasmic Ca2+ and the levels of the autophagy markers LC3-II and p62, in conjunction with a decrease in the BTB junction proteins occludin, claudin-11, and Cx43, with the dislocation of the gap junction protein Cx43. Meanwhile, inhibition of autophagy by CQ and 3-MA or inhibition of cytoplasmic Ca2+ by BAPTA-AM was sufficient to reduce the effects of ZEA on the TM4 cell BTB. To summarize, this study emphasizes the role of Ca2+-mediated autophagy in ZEA-induced BTB destruction, which deepens our understanding of the molecular mechanism of ZEA-induced male reproductive disorders.
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Affiliation(s)
- Jinjin She
- College of Veterinary Medicine, Yangzhou University, 12 Wenhui East Road, Yangzhou 225009, China; (J.S.); (N.F.); (W.Z.); (H.Z.); (P.C.); (H.Z.); (Y.Y.); (J.G.); (Z.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
| | - Nannan Feng
- College of Veterinary Medicine, Yangzhou University, 12 Wenhui East Road, Yangzhou 225009, China; (J.S.); (N.F.); (W.Z.); (H.Z.); (P.C.); (H.Z.); (Y.Y.); (J.G.); (Z.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Wanglong Zheng
- College of Veterinary Medicine, Yangzhou University, 12 Wenhui East Road, Yangzhou 225009, China; (J.S.); (N.F.); (W.Z.); (H.Z.); (P.C.); (H.Z.); (Y.Y.); (J.G.); (Z.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Hao Zheng
- College of Veterinary Medicine, Yangzhou University, 12 Wenhui East Road, Yangzhou 225009, China; (J.S.); (N.F.); (W.Z.); (H.Z.); (P.C.); (H.Z.); (Y.Y.); (J.G.); (Z.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Peirong Cai
- College of Veterinary Medicine, Yangzhou University, 12 Wenhui East Road, Yangzhou 225009, China; (J.S.); (N.F.); (W.Z.); (H.Z.); (P.C.); (H.Z.); (Y.Y.); (J.G.); (Z.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Hui Zou
- College of Veterinary Medicine, Yangzhou University, 12 Wenhui East Road, Yangzhou 225009, China; (J.S.); (N.F.); (W.Z.); (H.Z.); (P.C.); (H.Z.); (Y.Y.); (J.G.); (Z.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Yan Yuan
- College of Veterinary Medicine, Yangzhou University, 12 Wenhui East Road, Yangzhou 225009, China; (J.S.); (N.F.); (W.Z.); (H.Z.); (P.C.); (H.Z.); (Y.Y.); (J.G.); (Z.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Jianhong Gu
- College of Veterinary Medicine, Yangzhou University, 12 Wenhui East Road, Yangzhou 225009, China; (J.S.); (N.F.); (W.Z.); (H.Z.); (P.C.); (H.Z.); (Y.Y.); (J.G.); (Z.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Zongping Liu
- College of Veterinary Medicine, Yangzhou University, 12 Wenhui East Road, Yangzhou 225009, China; (J.S.); (N.F.); (W.Z.); (H.Z.); (P.C.); (H.Z.); (Y.Y.); (J.G.); (Z.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
| | - Jianchun Bian
- College of Veterinary Medicine, Yangzhou University, 12 Wenhui East Road, Yangzhou 225009, China; (J.S.); (N.F.); (W.Z.); (H.Z.); (P.C.); (H.Z.); (Y.Y.); (J.G.); (Z.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
- Correspondence:
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Lei WL, Li YY, Meng TG, Ning Y, Sun SM, Zhang CH, Gui Y, Wang ZB, Qian WP, Sun QY. Specific deletion of protein phosphatase 6 catalytic subunit in Sertoli cells leads to disruption of spermatogenesis. Cell Death Dis 2021; 12:883. [PMID: 34580275 PMCID: PMC8476514 DOI: 10.1038/s41419-021-04172-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 08/25/2021] [Accepted: 09/15/2021] [Indexed: 12/14/2022]
Abstract
Protein phosphatase 6 (PP6) is a member of the PP2A-like subfamily, which plays significant roles in numerous fundamental biological activities. We found that PPP6C plays important roles in male germ cells recently. Spermatogenesis is supported by the Sertoli cells in the seminiferous epithelium. In this study, we crossed Ppp6cF/F mice with AMH-Cre mice to gain mutant mice with specific depletion of the Ppp6c gene in the Sertoli cells. We discovered that the PPP6C cKO male mice were absolutely infertile and germ cells were largely lost during spermatogenesis. By combing phosphoproteome with bioinformatics analysis, we showed that the phosphorylation status of β-catenin at S552 (a marker of adherens junctions) was significantly upregulated in mutant mice. Abnormal β-catenin accumulation resulted in impaired testicular junction integrity, thus led to abnormal structure and functions of BTB. Taken together, our study reveals a novel function for PPP6C in male germ cell survival and differentiation by regulating the cell-cell communication through dephosphorylating β-catenin at S552.
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Affiliation(s)
- Wen-Long Lei
- Department of Reproductive Medicine, Peking University Shenzhen Hospital, Shenzhen, 518036, China
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Institute of Urology, Peking University Shenzhen Hospital, Shenzhen PKU-HKUST Medical Center, Shenzhen, 518036, China
| | - Yuan-Yuan Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Tie-Gang Meng
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- Fertility Preservation Lab, Guangdong-Hong Kong Metabolism & Reproduction Joint Laboratory, Reproductive Medicine Center, Guangdong Second Provincial General Hospital, Guangzhou, 510317, China
| | - Yan Ning
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Si-Min Sun
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Chun-Hui Zhang
- Department of Reproductive Medicine, Peking University Shenzhen Hospital, Shenzhen, 518036, China
- Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Institute of Urology, Peking University Shenzhen Hospital, Shenzhen PKU-HKUST Medical Center, Shenzhen, 518036, China
| | - Yaoting Gui
- Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Institute of Urology, Peking University Shenzhen Hospital, Shenzhen PKU-HKUST Medical Center, Shenzhen, 518036, China
| | - Zhen-Bo Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Wei-Ping Qian
- Department of Reproductive Medicine, Peking University Shenzhen Hospital, Shenzhen, 518036, China.
- Guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Institute of Urology, Peking University Shenzhen Hospital, Shenzhen PKU-HKUST Medical Center, Shenzhen, 518036, China.
| | - Qing-Yuan Sun
- Fertility Preservation Lab, Guangdong-Hong Kong Metabolism & Reproduction Joint Laboratory, Reproductive Medicine Center, Guangdong Second Provincial General Hospital, Guangzhou, 510317, China.
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9
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Wu S, Li H, Wang L, Mak N, Wu X, Ge R, Sun F, Cheng CY. Motor Proteins and Spermatogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1288:131-159. [PMID: 34453735 DOI: 10.1007/978-3-030-77779-1_7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Unlike the intermediate filament- and septin-based cytoskeletons which are apolar structures, the microtubule (MT) and actin cytoskeletons are polarized structures in mammalian cells and tissues including the testis, most notable in Sertoli cells. In the testis, these cytoskeletons that stretch across the epithelium of seminiferous tubules and lay perpendicular to the basement membrane of tunica propria serve as tracks for corresponding motor proteins to support cellular cargo transport. These cargoes include residual bodies, phagosomes, endocytic vesicles and most notably developing spermatocytes and haploid spermatids which lack the ultrastructures of motile cells (e.g., lamellipodia, filopodia). As such, these developing germ cells require the corresponding motor proteins to facilitate their transport across the seminiferous epithelium during the epithelial cycle of spermatogenesis. Due to the polarized natures of these cytoskeletons with distinctive plus (+) and minus (-) end, directional cargo transport can take place based on the use of corresponding actin- or MT-based motor proteins. These include the MT-based minus (-) end directed motor proteins: dyneins, and the plus (+) end directed motor proteins: kinesins, as well as the actin-based motor proteins: myosins, many of which are plus (+) end directed but a few are also minus (-) end directed motor proteins. Recent studies have shown that these motor proteins are essential to support spermatogenesis. In this review, we briefly summarize and evaluate these recent findings so that this information will serve as a helpful guide for future studies and for planning functional experiments to better understand their role mechanistically in supporting spermatogenesis.
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Affiliation(s)
- Siwen Wu
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Zhejiang, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Huitao Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Zhejiang, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Lingling Wang
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Zhejiang, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA.,Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
| | - Nathan Mak
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Xiaolong Wu
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
| | - Renshan Ge
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Zhejiang, China
| | - Fei Sun
- Sir Run Run Shaw Hospital (SRRSH), Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - C Yan Cheng
- Sir Run Run Shaw Hospital (SRRSH), Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
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10
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Wang L, Yan M, Wong CKC, Ge R, Wu X, Sun F, Cheng CY. Microtubule-associated proteins (MAPs) in microtubule cytoskeletal dynamics and spermatogenesis. Histol Histopathol 2020; 36:249-265. [PMID: 33174615 DOI: 10.14670/hh-18-279] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The microtubule (MT) cytoskeleton in Sertoli cells, a crucial cellular structure in the seminiferous epithelium of adult mammalian testes that supports spermatogenesis, was studied morphologically decades ago. However, its biology, in particular the involving regulatory biomolecules and the underlying mechanism(s) in modulating MT dynamics, are only beginning to be revealed in recent years. This lack of studies in delineating the biology of MT cytoskeletal dynamics undermines other studies in the field, in particular the plausible therapeutic treatment and management of male infertility and fertility since studies have shown that the MT cytoskeleton is one of the prime targets of toxicants. Interestingly, much of the information regarding the function of actin-, MT- and intermediate filament-based cytoskeletons come from studies using toxicant models including some genetic models. During the past several years, there have been some advances in studying the biology of MT cytoskeleton in the testis, and many of these studies were based on the use of pharmaceutical/toxicant models. In this review, we summarize the results of these findings, illustrating the importance of toxicant/pharmaceutical models in unravelling the biology of MT dynamics, in particular the role of microtubule-associated proteins (MAPs), a family of regulatory proteins that modulate MT dynamics but also actin- and intermediate filament-based cytoskeletons. We also provide a timely hypothetical model which can serve as a guide to design functional experiments to study how the MT cytoskeleton is regulated during spermatogenesis through the use of toxicants and/or pharmaceutical agents.
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Affiliation(s)
- Lingling Wang
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA.,Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Ming Yan
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Chris K C Wong
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Kowloon, Hong Kong, China
| | - Renshan Ge
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiaolong Wu
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
| | - Fei Sun
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA.,The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.
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11
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Wang L, Yan M, Wu S, Mao B, Wong CKC, Ge R, Sun F, Cheng CY. Microtubule Cytoskeleton and Spermatogenesis-Lesson From Studies of Toxicant Models. Toxicol Sci 2020; 177:305-315. [PMID: 32647867 PMCID: PMC7548287 DOI: 10.1093/toxsci/kfaa109] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Studies have shown that mammalian testes, in particular the Sertoli cells, are highly susceptible to exposure of environmental toxicants, such as cadmium, perfluorooctanesulfonate, phthalates, 2,5-hexanedione and bisphenol A. However, important studies conducted by reproductive toxicologists and/or biologists in the past have been treated as toxicology reports per se. Yet, many of these studies provided important mechanistic insights on the toxicant-induced testis injury and reproductive dysfunction, relevant to the biology of the testis and spermatogenesis. Furthermore, recent studies have shown that findings obtained from toxicant models are exceedingly helpful tools to unravel the biology of testis function in particular spermatogenesis, including specific cellular events associated with spermatid transport to support spermiogenesis and spermiation. In this review, we critically evaluate some recent data, focusing primarily on the molecular structure and role of microtubules in cellular function, illustrating the importance of toxicant models to unravel the biology of microtubule cytoskeleton in supporting spermatogenesis, well beyond information on toxicology. These findings have opened up some potential areas of research which should be carefully evaluated in the years to come.
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Affiliation(s)
- Lingling Wang
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu 210009, China
| | - Ming Yan
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu 210009, China
| | - Siwen Wu
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu 210009, China
| | - Baiping Mao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu 210009, China
| | - Chris K C Wong
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Kowloon, Hong Kong, China
| | - Renshan Ge
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Fei Sun
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu 226001, China
| | - C Yan Cheng
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu 226001, China
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12
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Wang L, Yan M, Wu S, Wu X, Bu T, Wong CK, Ge R, Sun F, Cheng CY. Actin binding proteins, actin cytoskeleton and spermatogenesis – Lesson from toxicant models. Reprod Toxicol 2020; 96:76-89. [DOI: 10.1016/j.reprotox.2020.05.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/15/2020] [Accepted: 05/30/2020] [Indexed: 12/16/2022]
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TOPK promotes metastasis of esophageal squamous cell carcinoma by activating the Src/GSK3β/STAT3 signaling pathway via γ-catenin. BMC Cancer 2019; 19:1264. [PMID: 31888532 PMCID: PMC6937732 DOI: 10.1186/s12885-019-6453-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 12/11/2019] [Indexed: 11/29/2022] Open
Abstract
Background Esophageal squamous cell carcinoma (ESCC) is a fatal disease with poor prognosis. The predominant reason for ESCC-related death is distal metastasis. A comprehensive understanding of the molecular mechanism underlying metastasis is needed for improving patient prognosis. T-LAK cell-originated protein kinase (TOPK) is a MAPKK-like kinase, which plays a vital role in various physiological and pathophysiological processes. However, the role of TOPK in ESCC metastasis is unclear. Methods Tissue array was used to evaluate the correlation between TOPK expression and ESCC lymph node metastasis. Wound healing assay, transwell assay, and lung metastasis mice model were used to examine the role of TOPK in the migration of ESCC cells in vitro and in vivo. Protein kinase array, mass spectrometry (MS), and molecular modeling were used to examine the pathways and direct target proteins of TOPK that are involved in ESCC metastasis. Additionally, immunofluorescence and western blotting analyses were performed to verify these findings. Results The enhanced expression of TOPK was correlated with lymph node metastasis in the ESCC tissues. TOPK knockdown or treatment with the TOPK inhibitor (HI-TOPK-032) decreased the invasion and migration of ESCC cells in vitro. HI-TOPK-032 also inhibited the lung metastasis in ESCC cell xenograft in vivo model. Moreover, TOPK promoted the invasion of ESCC cells by activating the Src/GSK3β/STAT3 and ERK signaling pathways via γ-catenin. Conclusion The findings of this study reveal that TOPK is involved in ESCC metastasis and promoted the ESCC cell mobility by activating the Src/GSK3β/STAT3 and ERK signaling pathways. This indicated that TOPK may be a potential molecular therapeutic target for ESCC metastasis.
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14
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Pinto TMF, Moreira RF, Matos MNC, Soares VVM, Aguiar MVDA, de Aragão PDTTD, Alves JG, Moreno FBMB, Monteiro-Moreira ACDO, Costa CRR, de Lima JL, Eloy AMX, da Cunha RMS. Evaluation of the proteomic profiles of ejaculated spermatozoa from Saanen bucks ( Capra hircus ). Anim Reprod 2019; 16:902-913. [PMID: 32368270 PMCID: PMC7189512 DOI: 10.21451/1984-3143-ar2019-0001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 09/02/2019] [Indexed: 01/04/2023] Open
Abstract
The Saanen goat breed has been widely explored in breeding programmes; however, there are few reports about the breed's genetic and molecular composition. Thus, this study aimed to characterize the proteomic profile of spermatozoa from Saanen breeding goats. Five breeding animals with proven fertility were selected, the spermatozoa were collected, and the protein was extracted. Subsequently, the proteins were separated and analysed by two-dimensional electrophoresis and mass spectrometry; the proteins were then identified with the SwissProt database. A total of 31 proteins involved in reproduction were identified, including binding proteins on spermatozoa for fusion with the egg, acrosomal membrane proteins, metabolic enzymes, heat shock proteins, cytoskeletal proteins and spermatozoa motility proteins. The characterization of such proteins clarifies the molecular mechanisms of spermatogenesis and the modifications that ensure the success of fertilization.
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Affiliation(s)
- Tatiana Maria Farias Pinto
- Universidade Estadual Vale do AcaraúLaboratorio de Biologia MolecularSobralBrasilUniversidade Estadual Vale do Acaraú, Laboratorio de Biologia Molecular, Sobral, Brasil
| | - Raulzito Fernandes Moreira
- Universidade Estadual Vale do AcaraúLaboratorio de Biologia MolecularSobralBrasilUniversidade Estadual Vale do Acaraú, Laboratorio de Biologia Molecular, Sobral, Brasil
| | - Maria Nagila Carneiro Matos
- Universidade Estadual Vale do AcaraúLaboratorio de Biologia MolecularSobralBrasilUniversidade Estadual Vale do Acaraú, Laboratorio de Biologia Molecular, Sobral, Brasil
| | - Vitória Virginia Magalhães Soares
- Universidade Estadual Vale do AcaraúLaboratorio de Biologia MolecularSobralBrasilUniversidade Estadual Vale do Acaraú, Laboratorio de Biologia Molecular, Sobral, Brasil
| | - Mônica Valeria de Almeida Aguiar
- Universidade Estadual Vale do AcaraúLaboratorio de Biologia MolecularSobralBrasilUniversidade Estadual Vale do Acaraú, Laboratorio de Biologia Molecular, Sobral, Brasil
| | - Paulo de Tarso Teles Dourado de Aragão
- Universidade Estadual Vale do AcaraúLaboratorio de Biologia MolecularSobralBrasilUniversidade Estadual Vale do Acaraú, Laboratorio de Biologia Molecular, Sobral, Brasil
| | - João Garcia Alves
- Universidade Estadual Vale do AcaraúLaboratorio de Biologia MolecularSobralBrasilUniversidade Estadual Vale do Acaraú, Laboratorio de Biologia Molecular, Sobral, Brasil
| | - Frederico Bruno Mendes Batista Moreno
- Universidade de FortalezaNúcleo de Biologia ExperimentalFortalezaBrasilUniversidade de Fortaleza, Núcleo de Biologia Experimental, Fortaleza, Brasil
| | | | - Cíntia Renata Rocha Costa
- Universidade Federal de Pernambuco FederalDepartamento de BioquímicaLaboratório de Imunopatologia Keizo AsamiRecifeBrasilUniversidade Federal de Pernambuco Federal, Departamento de Bioquímica, Laboratório de Imunopatologia Keizo Asami, Recife, Brasil
| | - José Luiz de Lima
- Universidade Federal de Pernambuco FederalDepartamento de BioquímicaLaboratório de Imunopatologia Keizo AsamiRecifeBrasilUniversidade Federal de Pernambuco Federal, Departamento de Bioquímica, Laboratório de Imunopatologia Keizo Asami, Recife, Brasil
| | - Angela Maria Xavier Eloy
- Centro de Pesquisa Caprinos e OvinosEmpresa Brasileira de Pesquisa AgropecuáriaSobralBrasilCentro de Pesquisa Caprinos e Ovinos, Empresa Brasileira de Pesquisa Agropecuária, Sobral, Brasil
| | - Rodrigo Maranguape Silva da Cunha
- Universidade Estadual Vale do AcaraúLaboratorio de Biologia MolecularSobralBrasilUniversidade Estadual Vale do Acaraú, Laboratorio de Biologia Molecular, Sobral, Brasil
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15
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Jiang YP, Ye RJ, Yang JM, Liu N, Zhang WJ, Ma L, Sun T, Niu JG, Zheng P, Yu JQ. Protective effects of Salidroside on spermatogenesis in streptozotocin induced type-1 diabetic male mice by inhibiting oxidative stress mediated blood-testis barrier damage. Chem Biol Interact 2019; 315:108869. [PMID: 31682803 DOI: 10.1016/j.cbi.2019.108869] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 09/10/2019] [Accepted: 10/21/2019] [Indexed: 12/14/2022]
Abstract
Spermatogenic dysfunction is one of the major secondary complications of male diabetes. Salidroside (SAL) is the important active ingredients isolated from Herba Cistanche, which exhibits numerous pharmacological activities such as antioxidant, anti-diabetic, and anti-inflammatory effects. The present study was designed to determine whether SAL contributes to the recovery from spermatogenic dysfunction in streptozotocin (STZ) induced type-1 diabetic mice. SAL (25, 50, or 100 mg/kg) and Clomiphene citrate (CC, 5 mg/kg) were orally administered to male type-1 diabetic mice for 10 weeks. Testis tissues were collected for histopathological and biochemical analysis. Moreover, reproductive organ weight, sperm parameters, and testicular cell DNA damage were estimated. The results revealed that SAL significantly improved the weight of the reproductive organs, sperm parameters and testicular morphology to different degrees in type-1 diabetic mice. Furthermore, reactive oxygen species (ROS) and malondialdehyde (MDA) levels were significantly reduced, and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), markedly increased in the testicular tissue after SAL treatment. In addition, our data also showed a marked downregulation the fluorescence expressions of p38 MAPK phosphorylation and upregulation the protein expressions of ZO-1, Occludin, Claudin-11 and N-cadherin after SAL administration (100 mg/kg) compared with the type-1 diabetic group. In conclusion, these results demonstrated that SAL exerts protective effects on type-1 diabetes-induced male spermatogenic dysfunction, which is likely mediated by inhibiting oxidative stress-mediated blood testis barrier damage.
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Affiliation(s)
- Ya-Ping Jiang
- Department of Pharmacology, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China
| | - Rui-Juan Ye
- Department of Pharmacology, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China
| | - Jia-Mei Yang
- Department of Pharmacology, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China
| | - Ning Liu
- Department of Pharmacology, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China
| | - Wen-Jin Zhang
- Department of Pharmacology, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China
| | - Lin Ma
- Ningxia Key Laboratory of Craniocerebral Diseases of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China
| | - Tao Sun
- Ningxia Key Laboratory of Craniocerebral Diseases of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China
| | - Jian-Guo Niu
- Ningxia Key Laboratory of Craniocerebral Diseases of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China.
| | - Ping Zheng
- Department of Pharmacology, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China.
| | - Jian-Qiang Yu
- Department of Pharmacology, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China; Ningxia Hui Medicine Modern Engineering Research Center and Collaborative Innovation Center, Ningxia Medical University, Yinchuan, Ningxia Hui Autonomous Region, 750004, PR China.
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16
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Protective effects of betaine on diabetic induced disruption of the male mice blood-testis barrier by regulating oxidative stress-mediated p38 MAPK pathways. Biomed Pharmacother 2019; 120:109474. [PMID: 31585299 DOI: 10.1016/j.biopha.2019.109474] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/17/2019] [Accepted: 09/18/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Blood-testis barrier (BTB) impairments is one of the major secondary complications of diabetes. Betaine (BET) is the important active ingredients isolated from Lycium barbarum, which exhibits numerous pharmacological activities such as antioxidant, anti-diabetic, and anti-inflammatory effects. This study aimed to establish whether BET contributes to the recovery from BTB dysfunction in streptozotocin (STZ) induced diabetic mice. METHODS BET (200, 400, 800 mg/kg) was orally administered to diabetic mice for 8 weeks. Testis tissues were collected for histopathological and biochemical analysis, the reproductive organ weight was estimated. Antioxidant enzyme activity and BTB associated protein expressions were determined with their corresponding assay kits and western blot analysis. The results revealed that BET significantly improved the weight of the reproductive organs and testicular morphology in diabetic mice. Furthermore, reactive oxygen species (ROS) and malondialdehyde (MDA) levels were significantly reduced, and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), markedly increased in the testicular tissue after SAL treatment. In addition, our data also showed a marked down-regulated the expressions of p38 MAPK phosphorylation and up-regulation the protein expressions of ZO-1, Occludin, Claudin-11, N-cadherin, and Connexin-43 after BET administration compared with the diabetic group. In conclusion, these results demonstrated that BET exerts protective effects on diabetes-induced BTB dysfunction, which may be through regulating oxidative stress-mediated p38 MAPK pathways.
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17
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Hejmej A, Bilinska B. The effects of flutamide on cell-cell junctions in the testis, epididymis, and prostate. Reprod Toxicol 2018; 81:1-16. [PMID: 29958919 DOI: 10.1016/j.reprotox.2018.06.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 06/15/2018] [Accepted: 06/20/2018] [Indexed: 12/12/2022]
Abstract
In this review, we summarize recent findings on the effect of the anti-androgen flutamide on cell-cell junctions in the male reproductive system. We outline developmental aspects of flutamide action on the testis, epididymis, and prostate, and describe changes in junction protein expression and organization of junctional complexes in the adult boar following prenatal and postnatal exposure. We also discuss findings on the mechanisms by which flutamide induces alterations in cell-cell junctions in reproductive tissues of adult males, with special emphasis on cytoplasmic effects. Based on the results from in vivo and in vitro studies in the rat, we propose that flutamide affects the expression of junction proteins and junction complex structure not only by inhibiting androgen receptor activity, but equally important by modulating protein kinase-dependent signaling in testicular cells. Additionally, results from studies on prostate cancer cell lines point to a role for the cellular molecular outfit in response to flutamide.
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Affiliation(s)
- Anna Hejmej
- Department of Endocrinology, Institute of Zoology and Biomedical Research, Jagiellonian University, Krakow, Poland
| | - Barbara Bilinska
- Department of Endocrinology, Institute of Zoology and Biomedical Research, Jagiellonian University, Krakow, Poland.
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18
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Yi WEI, Xiang-Liang T, Yu Z, Bin L, Lian-Ju S, Chun-Lan L, Tao LIN, Da-Wei HE, Sheng-de WU, Guang-Hui WEI. DEHP exposure destroys blood-testis barrier (BTB) integrity of immature testes through excessive ROS-mediated autophagy. Genes Dis 2018; 5:263-274. [PMID: 30320191 PMCID: PMC6176266 DOI: 10.1016/j.gendis.2018.06.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 06/19/2018] [Indexed: 01/09/2023] Open
Abstract
Di-(2-ethylhexyl) phthalate (DEHP), is known to impair testicular functions and reproduction. However, its effects on immature testis Blood-testis barrier (BTB) and the underlying mechanisms remain obscure. We constructed a rat model to investigate the roles of autophagy in BTB toxicity induced by DEHP. Sprague–Dawley rats were developmentally exposed to 0, 250 and 500 mg/kg DEHP via intragastric administration from postnatal day (PND) 1 to PND 35. Testicular morphology, expressions of BTB junction proteins and autophagy related proteins were detected. In addition, expressions of oxidative stress markers were also analyzed. Our results demonstrated that developmental DEHP exposure induced decreasing organ coefficients of immature testes and severe testicular damage in histomorphology. The expressions of junctional proteins were down-regulated significantly after DEHP treatment. Intriguingly, DEHP simultaneously increased the number of autophagosomes and the levels of autophagy marker LC3-II and p62, suggesting that the accumulated autophagosomes resulted from impaired autophagy degradation. Moreover, the expressions of HO-1 and SOD levels remarkably decreased after DEHP exposure. Vitamins E and C could alleviate the DEHP-induced oxidative stress, reverse the autophagy defect and restore the BTB impairment. Taken together, DEHP exposure destroys immature testis blood-testis barrier (BTB) integrity through excessive ROS-mediated autophagy.
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Affiliation(s)
- W E I Yi
- Department of Urology, Children's Hospital of Chongqing Medical University, Zhongshan 2RD, Yuzhong District, Chongqing, 400014, China.,Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China.,Chongqing Key Laboratory of Pediatrics Chongqing, China
| | - Tang Xiang-Liang
- Department of Urology, Children's Hospital of Chongqing Medical University, Zhongshan 2RD, Yuzhong District, Chongqing, 400014, China.,Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China
| | - Zhou Yu
- Department of Urology, Children's Hospital of Chongqing Medical University, Zhongshan 2RD, Yuzhong District, Chongqing, 400014, China.,Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China
| | - Liu Bin
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China.,Ministry of Education Key Laboratory of Child Development and Disorders, China
| | - Shen Lian-Ju
- Department of Urology, Children's Hospital of Chongqing Medical University, Zhongshan 2RD, Yuzhong District, Chongqing, 400014, China.,Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China.,Chongqing Key Laboratory of Pediatrics Chongqing, China
| | - Long Chun-Lan
- Department of Urology, Children's Hospital of Chongqing Medical University, Zhongshan 2RD, Yuzhong District, Chongqing, 400014, China.,Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China
| | - L I N Tao
- Department of Urology, Children's Hospital of Chongqing Medical University, Zhongshan 2RD, Yuzhong District, Chongqing, 400014, China.,Ministry of Education Key Laboratory of Child Development and Disorders, China
| | - H E Da-Wei
- Department of Urology, Children's Hospital of Chongqing Medical University, Zhongshan 2RD, Yuzhong District, Chongqing, 400014, China.,China International Science and Technology Cooperation Base of Child Development and Critical Disorders, China
| | - W U Sheng-de
- Department of Urology, Children's Hospital of Chongqing Medical University, Zhongshan 2RD, Yuzhong District, Chongqing, 400014, China.,Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China
| | - W E I Guang-Hui
- Department of Urology, Children's Hospital of Chongqing Medical University, Zhongshan 2RD, Yuzhong District, Chongqing, 400014, China.,Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering, China.,Ministry of Education Key Laboratory of Child Development and Disorders, China.,China International Science and Technology Cooperation Base of Child Development and Critical Disorders, China.,Chongqing Key Laboratory of Pediatrics Chongqing, China
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19
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Mruk DD, Bonanomi M, Silvestrini B. Lonidamine-ethyl ester-mediated remodelling of the Sertoli cell cytoskeleton induces phosphorylation of plakoglobin and promotes its interaction with α-catenin at the blood–testis barrier. Reprod Fertil Dev 2017; 29:998-1011. [DOI: 10.1071/rd15378] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Accepted: 01/27/2016] [Indexed: 12/22/2022] Open
Abstract
Several compounds affect male fertility by disrupting the adhesion of germ cells to Sertoli cells, which results in the release of undeveloped germ cells into the seminiferous tubule lumen that are incapable of fertilising the ovum. Indazole carboxylic acids are one class of compounds exhibiting such effects and they have been investigated as non-hormonal contraceptives for potential human use. The aims of this study were to investigate the effects of lonidamine-ethyl ester, an indazole carboxylic acid, on spermatogenesis and cell junctions, in particular, desmosomes. We found two doses of lonidamine-ethyl ester at 50 mg kg–1 to disrupt Sertoli–germ cell adhesion. By light and fluorescent microscopy, pronounced changes were observed in the distribution of actin microfilaments and intermediate filaments, as well as in the localisation of plakoglobin, a protein with structural and signalling roles at the desmosome and adherens junction at the blood–testis barrier. Furthermore, immunoblotting and immunoprecipitation experiments using testis lysates revealed a significant upregulation (P < 0.01) of plakoglobin and Tyr-phosphorylated plakoglobin. Co-immunoprecipitation experiments showed an increase in the interaction between plakoglobin and fyn proto-oncogene, an Src family non-receptor tyrosine kinase, after treatment, as well as an increase in the interaction between plakoglobin and α-catenin. Taken collectively, these data indicate that a disruption of Sertoli cell and spermatocyte–spermatid adhesion in the seminiferous epithelium by lonidamine-ethyl ester results in the phosphorylation of plakoglobin, thereby promoting its interaction with α-catenin at the blood–testis barrier.
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Huang W, Quan C, Duan P, Tang S, Chen W, Yang K. Nonylphenol induced apoptosis and autophagy involving the Akt/mTOR pathway in prepubertal Sprague-Dawley male rats in vivo and in vitro. Toxicology 2016; 373:41-53. [PMID: 27832966 DOI: 10.1016/j.tox.2016.11.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 11/02/2016] [Accepted: 11/05/2016] [Indexed: 01/14/2023]
Abstract
This research explores the detrimental effect of nonylphenol (NP) to prepubertal Sprague-Dawley male rats in vivo and in vitro. Herein, forty-two 3-week-old rats were randomly divided into six groups, which were treated with NP (0, NAC, 25, 50, 100, 100+NACmg/kg/2d for 30 consecutive days) by intraperitoneal injection. NP induced a reduction in testosterone (15.58%, 17.23%, 13.38% in 25, 50, 100mg/kg group, respectively), triggered apoptosis related to oxidative stress, and disturbed mRNA and/or protein levels of PI3K, PTEN, PDK1, p-Akt, p-mTOR, p70S6K, caspase-3, LC3B. NP induced morphological abnormality in epididymal sperm (2.00-, 3.02-fold in 50, 100mg/kg group, respectively). Pretreatment with NAC, attenuated NP-induced ROS production; recovered testosterone in serum, and ameliorated toxic effect in epididymal sperm. Sertoli cells were isolated, purified, treated with NP (0, 10, 20, and 30μM) for 12h. NP disturbed mRNA and/or protein levels of caspase-3, cleave-caspase-3, LC3B involving the PI3K/Akt/mTOR pathway. It also decreased protein levels of ABP, FSHR, N-cadherin, transferrin, vimentin; disturbed the gene levels of all, but vimentin. Pretreatment with wortmannin, alleviated an NP-induced reduction in protein levels of PI3K and PTEN. In conclusion, excess NP exposure induces apoptosis and autophagy, causes reproductive lesions involving the PI3K/AKT/mTOR pathway both in vivo and in vitro. It also triggers oxidative stress and hormonal deficiency, reduces semen quality.
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Affiliation(s)
- Wenting Huang
- MOE Key Laboratory of Environment and Health, Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, PR China
| | - Chao Quan
- MOE Key Laboratory of Environment and Health, Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, PR China
| | - Peng Duan
- MOE Key Laboratory of Environment and Health, Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, PR China
| | - Sha Tang
- MOE Key Laboratory of Environment and Health, Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, PR China
| | - Wei Chen
- MOE Key Laboratory of Environment and Health, Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, PR China
| | - Kedi Yang
- MOE Key Laboratory of Environment and Health, Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, PR China.
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21
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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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22
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Liu C, Wang H, Shang Y, Liu W, Song Z, Zhao H, Wang L, Jia P, Gao F, Xu Z, Yang L, Gao F, Li W. Autophagy is required for ectoplasmic specialization assembly in sertoli cells. Autophagy 2016; 12:814-32. [PMID: 26986811 DOI: 10.1080/15548627.2016.1159377] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The ectoplasmic specialization (ES) is essential for Sertoli-germ cell communication to support all phases of germ cell development and maturity. Its formation and remodeling requires rapid reorganization of the cytoskeleton. However, the molecular mechanism underlying the regulation of ES assembly is still largely unknown. Here, we show that Sertoli cell-specific disruption of autophagy influenced male mouse fertility due to the resulting disorganized seminiferous tubules and spermatozoa with malformed heads. In autophagy-deficient mouse testes, cytoskeleton structures were disordered and ES assembly was disrupted. The disorganization of the cytoskeleton structures might be caused by the accumulation of a negative cytoskeleton organization regulator, PDLIM1, and these defects could be partially rescued by Pdlim1 knockdown in autophagy-deficient Sertoli cells. Altogether, our works reveal that the degradation of PDLIM1 by autophagy in Sertoli cells is important for the proper assembly of the ES, and these findings define a novel role for autophagy in Sertoli cell-germ cell communication.
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Affiliation(s)
- Chao Liu
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China.,b University of Chinese Academy of Sciences , Beijing , China
| | - Hongna Wang
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China.,b University of Chinese Academy of Sciences , Beijing , China
| | - Yongliang Shang
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China.,b University of Chinese Academy of Sciences , Beijing , China
| | - Weixiao Liu
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China
| | - Zhenhua Song
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China.,b University of Chinese Academy of Sciences , Beijing , China
| | - Haichao Zhao
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China.,b University of Chinese Academy of Sciences , Beijing , China
| | - Lina Wang
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China.,b University of Chinese Academy of Sciences , Beijing , China
| | - Pengfei Jia
- c State Key Laboratory of Molecular Developmental Biology and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences , Beijing , China
| | - Fengyi Gao
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China
| | - Zhiliang Xu
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China.,b University of Chinese Academy of Sciences , Beijing , China
| | - Lin Yang
- c State Key Laboratory of Molecular Developmental Biology and National Center for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences , Beijing , China
| | - Fei Gao
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China.,b University of Chinese Academy of Sciences , Beijing , China
| | - Wei Li
- a State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China.,b University of Chinese Academy of Sciences , Beijing , China
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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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Mruk DD, Cheng CY. The Mammalian Blood-Testis Barrier: Its Biology and Regulation. Endocr Rev 2015; 36:564-91. [PMID: 26357922 PMCID: PMC4591527 DOI: 10.1210/er.2014-1101] [Citation(s) in RCA: 386] [Impact Index Per Article: 42.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 09/03/2015] [Indexed: 12/31/2022]
Abstract
Spermatogenesis is the cellular process by which spermatogonia develop into mature spermatids within seminiferous tubules, the functional unit of the mammalian testis, under the structural and nutritional support of Sertoli cells and the precise regulation of endocrine factors. As germ cells develop, they traverse the seminiferous epithelium, a process that involves restructuring of Sertoli-germ cell junctions, as well as Sertoli-Sertoli cell junctions at the blood-testis barrier. The blood-testis barrier, one of the tightest tissue barriers in the mammalian body, divides the seminiferous epithelium into 2 compartments, basal and adluminal. The blood-testis barrier is different from most other tissue barriers in that it is not only comprised of tight junctions. Instead, tight junctions coexist and cofunction with ectoplasmic specializations, desmosomes, and gap junctions to create a unique microenvironment for the completion of meiosis and the subsequent development of spermatids into spermatozoa via spermiogenesis. Studies from the past decade or so have identified the key structural, scaffolding, and signaling proteins of the blood-testis barrier. More recent studies have defined the regulatory mechanisms that underlie blood-testis barrier function. We review here the biology and regulation of the mammalian blood-testis barrier and highlight research areas that should be expanded in future studies.
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Affiliation(s)
- Dolores D Mruk
- Center for Biomedical Research, Population Council, New York, New York 10065
| | - C Yan Cheng
- Center for Biomedical Research, Population Council, New York, New York 10065
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25
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Vazquez-Levin MH, Marín-Briggiler CI, Caballero JN, Veiga MF. Epithelial and neural cadherin expression in the mammalian reproductive tract and gametes and their participation in fertilization-related events. Dev Biol 2015; 401:2-16. [DOI: 10.1016/j.ydbio.2014.12.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Revised: 12/23/2014] [Accepted: 12/28/2014] [Indexed: 01/10/2023]
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26
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Tang EI, Mok KW, Lee WM, Cheng CY. EB1 regulates tubulin and actin cytoskeletal networks at the sertoli cell blood-testis barrier in male rats: an in vitro study. Endocrinology 2015; 156:680-93. [PMID: 25456071 PMCID: PMC4298315 DOI: 10.1210/en.2014-1720] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
During spermatogenesis, developing germ cells are transported across the seminiferous epithelium. Studies propose that because microtubules (MTs) serve as the tracks for transporting cell organelles, they may also serve a similar function in the transport of developing germ cells. Polarized MTs may provide the tracks along which polarized actin microfilaments, which act as vehicles to transport cargo, such as preleptotene spermatocytes through the blood-testis barrier (BTB) and spermatids across the epithelium. Yet the molecular mechanism(s) underlying these events remain unknown. Using an established in vitro Sertoli cell system to study BTB function, we demonstrated herein that a MT regulatory protein end-binding protein 1 (EB1) regulates the MT- and also the actin-based cytoskeleton of the Sertoli cell BTB in the rat. EB1 serves as a coordinator between the two cytoskeletons by regulating MT polymerization and actin filament bundling to modulate germ cell transport at the Sertoli cell BTB. A knockdown of EB1 by RNA interference was found to perturb the tight junction (TJ)-permeability barrier, as evidenced by mislocalization of junctional proteins critical for barrier function to facilitate spermatocyte transport, which was likely achieved by two coordinated events. First, EB1 knockdown resulted in changes in MT polymerization, thereby perturbing MT organization in Sertoli cells in which polarized MT no longer stretched properly across the cell cytosol to serve as the tracks. Second, EB1 knockdown perturbed actin organization via its effects on the branched actin polymerization-inducing protein called Arp3 (actin-related protein 3), perturbing microfilament bundling capability based on a biochemical assay, thereby causing microfilament truncation and misorganization, disrupting the function of the vehicle. This reduced actin microfilament bundling capability thus perturbed TJ-protein distribution and localization at the BTB, destabilizing the TJ barrier, leading to its remodeling to facilitate spermatocyte transport. In summary, EB1 provides a functional link between tubulin- and actin-based cytoskeletons to confer spermatocyte transport at the BTB.
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Affiliation(s)
- Elizabeth I Tang
- The Mary M. Wohlford Laboratory for Male Contraceptive Research (E.I.T., K.-W.M., C.Y.C.), Center for Biomedical Research, Population Council, New York, New York 10065; and School of Biological Sciences (W.M.L.), University of Hong Kong, Hong Kong, China
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27
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Cheng CY. Toxicants target cell junctions in the testis: Insights from the indazole-carboxylic acid model. SPERMATOGENESIS 2015; 4:e981485. [PMID: 26413399 PMCID: PMC4581065 DOI: 10.4161/21565562.2014.981485] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 10/23/2014] [Indexed: 12/31/2022]
Abstract
There are numerous types of junctions in the seminiferous epithelium which are integrated with, and critically dependent on the Sertoli cell cytoskeleton. These include the basal tight junctions between Sertoli cells that form the main component of the blood–testis barrier, the basal ectoplasmic specializations (basal ES) and basal tubulobulbar complexes (basal TBC) between Sertoli cells; as well as apical ES and apical TBC between Sertoli cells and the developing spermatids that orchestrate spermiogenesis and spermiation. These junctions, namely TJ, ES, and TBC interact with actin microfilament-based cytoskeleton, which together with the desmosomal junctions that interact with the intermediate filament-based cytoskeleton plus the highly polarized microtubule-based cytoskeleton are working in concert to move spermatocytes and spermatids between the basal and luminal aspect of the seminiferous epithelium. In short, these various junctions are structurally complexed with the actin- and microtubule-based cytoskeleton or intermediate filaments of the Sertoli cell. Studies have shown toxicants (e.g., cadmium, bisphenol A (BPA), perfluorooctanesulfonate (PFOS), phthalates, and glycerol), and some male contraceptives under development (e.g., adjudin, gamendazole), exert their effects, at least in part, by targeting cell junctions in the testis. The disruption of Sertoli–Sertoli cell and Sertoli–germ cell junctions, results in the loss of germ cells from the seminiferous epithelium. Adjudin, a potential male contraceptive under investigation in our laboratory, produces loss of spermatids from the seminiferous tubules through disruption of the Sertoli cell spermatid junctions and disruption of the Sertoli cell cytoskeleton. The molecular and structural changes associated with adjudin administration are described, to provide an example of the profile of changes caused by disturbance of Sertoli-germ cell and also Sertoli cell-cell junctions.
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Affiliation(s)
- C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council ; New York, NY USA
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28
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Mruk DD, Cheng CY. Enhanced chemiluminescence (ECL) for routine immunoblotting: An inexpensive alternative to commercially available kits. SPERMATOGENESIS 2014; 1:121-122. [PMID: 22319660 DOI: 10.4161/spmg.1.2.16606] [Citation(s) in RCA: 189] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Accepted: 02/25/2011] [Indexed: 11/19/2022]
Abstract
Immunoblotting is an analytical technique used by many laboratories to study protein expression. It involves electrophoretic separation of proteins by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), immobilization of these proteins onto a membrane of either nitrocellulose or polyvinylidene difluoride, incubation of the membrane in a monoclonal or polyclonal antibody and detection by a standard method such as enhanced chemiluminescence (ECL). To achieve this, most laboratories opt to use commercially-available chemiluminescence kits which are acceptable but relatively expensive. In this technical report, we show that a self-prepared chemiluminescence reagent is superior to a commercially obtained kit in terms of sensitivity, duration of signal, ease-of-use and shelf-life but at a fraction of the cost of a kit.
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Affiliation(s)
- Dolores D Mruk
- Center for Biomedical Research; The Population Council; New York, NY USA
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29
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Mruk DD, Cheng CY. Testin and actin are key molecular targets of adjudin, an anti-spermatogenic agent, in the testis. SPERMATOGENESIS 2014; 1:137-146. [PMID: 22319662 DOI: 10.4161/spmg.1.2.16449] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 05/12/2011] [Indexed: 12/13/2022]
Abstract
Earlier studies have shown adjudin to cause aspermatogenesis by depleting virtually all germ cells from the seminiferous epithelium, leading to transient infertility; spermatogenesis and fertility were re-established several weeks later after germ cell proliferation and differentiation were reinitiated by spermatogonia. While adjudin is known to exert its initial effects at the apical ectoplasmic specialization (a testis-specific atypical anchoring junction), thereby perturbing spermatid adhesion, its molecular target(s) at this site is not known. Herein, we report the production of a specific antibody against adjudin after this compound was conjugated to an adjuvant (i.e., keyhole limpet hemocyanin) to maximize immune response in rabbits. This antibody was utilized for co-immunoprecipitation by using an affinity resin to pull-down the binding partners of adjudin. Using this approach coupled with mass spectrometry and immunoblotting, we show testin (a protein largely restricted to the apical ES in the adult testis) and actin-myosin to be molecular targets of adjudin. These findings provide a platform for future functional studies, not only to better understand the molecular mechanism behind adjudin-induced germ cell loss from the seminiferous epithelium, but also to understand the molecular basis of spermiation.
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Affiliation(s)
- Dolores D Mruk
- Center for Biomedical Research; The Population Council; New York, NY USA
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30
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Domke LM, Rickelt S, Dörflinger Y, Kuhn C, Winter-Simanowski S, Zimbelmann R, Rosin-Arbesfeld R, Heid H, Franke WW. The cell-cell junctions of mammalian testes: I. The adhering junctions of the seminiferous epithelium represent special differentiation structures. Cell Tissue Res 2014; 357:645-65. [PMID: 24907851 PMCID: PMC4148596 DOI: 10.1007/s00441-014-1906-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 04/28/2014] [Indexed: 01/08/2023]
Abstract
The seminiferous tubules and the excurrent ducts of the mammalian testis are physiologically separated from the mesenchymal tissues and the blood and lymph system by a special structural barrier to paracellular translocations of molecules and particles: the "blood-testis barrier", formed by junctions connecting Sertoli cells with each other and with spermatogonial cells. In combined biochemical as well as light and electron microscopical studies we systematically determine the molecules located in the adhering junctions of adult mammalian (human, bovine, porcine, murine, i.e., rat and mouse) testis. We show that the seminiferous epithelium does not contain desmosomes, or "desmosome-like" junctions, nor any of the desmosome-specific marker molecules and that the adhering junctions of tubules and ductules are fundamentally different. While the ductules contain classical epithelial cell layers with E-cadherin-based adherens junctions (AJs) and typical desmosomes, the Sertoli cells of the tubules lack desmosomes and "desmosome-like" junctions but are connected by morphologically different forms of AJs. These junctions are based on N-cadherin anchored in cytoplasmic plaques, which in some subforms appear thick and dense but in other subforms contain only scarce and loosely arranged plaque structures formed by α- and β-catenin, proteins p120, p0071 and plakoglobin, together with a member of the striatin family and also, in rodents, the proteins ZO-1 and myozap. These N-cadherin-based AJs also include two novel types of junctions: the "areae adhaerentes", i.e., variously-sized, often very large cell-cell contacts and small sieve-plate-like AJs perforated by cytoplasm-to-cytoplasm channels of 5-7 nm internal diameter ("cribelliform junctions"). We emphasize the unique character of this epithelium that totally lacks major epithelial marker molecules and structures such as keratin filaments and desmosomal elements as well as EpCAM- and PERP-containing junctions. We also discuss the nature, development and possible functions of these junctions.
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Affiliation(s)
- Lisa M. Domke
- Helmholtz Group for Cell Biology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
- Brandenburg University of Technology, Senftenberg, Germany
- Present Address: Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology (MIT), Cambridge, MA USA
| | - Steffen Rickelt
- Helmholtz Group for Cell Biology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Yvette Dörflinger
- Helmholtz Group for Cell Biology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Caecilia Kuhn
- Helmholtz Group for Cell Biology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
- Progen Biotechnik GmbH, Heidelberg, Germany
| | - Stefanie Winter-Simanowski
- Helmholtz Group for Cell Biology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Ralf Zimbelmann
- Helmholtz Group for Cell Biology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Rina Rosin-Arbesfeld
- Department of Anatomy, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Hans Heid
- Helmholtz Group for Cell Biology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Werner W. Franke
- Helmholtz Group for Cell Biology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
- Progen Biotechnik GmbH, Heidelberg, Germany
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31
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Wan HT, Mruk DD, Tang EI, Xiao X, Cheng YH, Wong EWP, Wong CKC, Cheng CY. Role of non-receptor protein tyrosine kinases in spermatid transport during spermatogenesis. Semin Cell Dev Biol 2014; 30:65-74. [PMID: 24727349 DOI: 10.1016/j.semcdb.2014.04.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Accepted: 04/04/2014] [Indexed: 12/16/2022]
Abstract
Non-receptor protein tyrosine kinases are cytoplasmic kinases that activate proteins by phosphorylating tyrosine residues, which in turn affect multiple functions in eukaryotic cells. Herein, we focus on the role of non-receptor protein tyrosine kinases, most notably, FAK, c-Yes and c-Src, in the transport of spermatids across the seminiferous epithelium during spermatogenesis. Since spermatids, which are formed from spermatocytes via meiosis, are immotile haploid cells, they must be transported by Sertoli cells across the seminiferous epithelium during the epithelial cycle of spermatogenesis. Without the timely transport of spermatids across the epithelium, the release of sperms at spermiation fails to occur, leading to infertility. Thus, the molecular event pertinent to spermatid transport is crucial to spermatogenesis. We provide a critical discussion based on recent findings in this review. We also provide a hypothetical model on spermatid transport, and the role of non-receptor protein tyrosine kinases in this event. We also highlight areas of research that deserve attention by investigators in the field.
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Affiliation(s)
- H T Wan
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States
| | - Dolores D Mruk
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States
| | - Elizabeth I Tang
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States
| | - Xiang Xiao
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States
| | - Yan-Ho Cheng
- Richmond University Medical Center, Staten Island, NY 10301, United States
| | - Elissa W P Wong
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States
| | - Chris K C Wong
- Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong, China
| | - C Yan Cheng
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States.
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32
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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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Abstract
During spermatogenesis, spermatids derived from meiosis simultaneously undergo extensive morphological transformation, to become highly specialized and metabolically quiescent cells, and transport across the seminiferous epithelium. Spermatids are also transported back-and-forth across the seminiferous epithelium during the epithelial cycle until they line up at the luminal edge of the tubule to prepare for spermiation at stage VIII of the cycle. Spermatid transport thus requires the intricate coordination of the cytoskeletons in Sertoli cells (SCs) as spermatids are nonmotile cells lacking the ultrastructures of lamellipodia and filopodia, as well as the organized components of the cytoskeletons. In the course of preparing this brief review, we were surprised to see that, except for some earlier eminent morphological studies, little is known about the regulation of the microtubule (MT) cytoskeleton and the coordination of MT with the actin-based cytoskeleton to regulate spermatid transport during the epithelia cycle, illustrating that this is a largely neglected area of research in the field. Herein, we summarize recent findings in the field regarding the significance of actin- and tubulin-based cytoskeletons in SCs that support spermatid transport; we also highlight specific areas of research that deserve attention in future studies.
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Affiliation(s)
- Elizabeth I Tang
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York, New York 10065, USA
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Qian X, Mruk DD, Cheng CY. Rai14 (retinoic acid induced protein 14) is involved in regulating f-actin dynamics at the ectoplasmic specialization in the rat testis*. PLoS One 2013; 8:e60656. [PMID: 23565266 PMCID: PMC3614988 DOI: 10.1371/journal.pone.0060656] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 03/01/2013] [Indexed: 01/31/2023] Open
Abstract
Rai14 (retinoic acid induced protein 14) is an actin binding protein first identified in the liver, highly expressed in the placenta, the testis, and the eye. In the course of studying actin binding proteins that regulate the organization of actin filament bundles in the ectoplasmic specialization (ES), a testis-specific actin-rich adherens junction (AJ) type, Rai14 was shown to be one of the regulatory proteins at the ES. In the rat testis, Rai14 was found to be expressed by Sertoli and germ cells, structurally associated with actin and an actin cross-linking protein palladin. Its expression was the highest at the ES in the seminiferous epithelium of adult rat testes, most notably at the apical ES at the Sertoli-spermatid interface, and expressed stage-specifically during the epithelial cycle in stage VII-VIII tubules. However, Rai14 was also found at the basal ES near the basement membrane, associated with the blood-testis barrier (BTB) in stage VIII-IX tubules. A knockdown of Rai14 in Sertoli cells cultured in vitro by RNAi was found to perturb the Sertoli cell tight junction-permeability function in vitro, mediated by a disruption of F-actin, which in turn led to protein mis-localization at the Sertoli cell BTB. When Rai14 in the testis in vivo was knockdown by RNAi, defects in spermatid polarity and adhesion, as well as spermatid transport were noted mediated via changes in F-actin organization and mis-localization of proteins at the apical ES. In short, Rai14 is involved in the re-organization of actin filaments in Sertoli cells during the epithelial cycle, participating in conferring spermatid polarity and cell adhesion in the testis.
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Affiliation(s)
- Xiaojing Qian
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, United States of America
- Department of Anatomy, Histology and Embryology, 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, United States of America
| | - C. Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, United States of America
- * E-mail:
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Xiao X, Mruk DD, Cheng CY. Intercellular adhesion molecules (ICAMs) and spermatogenesis. Hum Reprod Update 2013; 19:167-86. [PMID: 23287428 DOI: 10.1093/humupd/dms049] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND During the seminiferous epithelial cycle, restructuring takes places at the Sertoli-Sertoli and Sertoli-germ cell interface to accommodate spermatogonia/spermatogonial stem cell renewal via mitosis, cell cycle progression and meiosis, spermiogenesis and spermiation since developing germ cells, in particular spermatids, move 'up and down' the seminiferous epithelium. Furthermore, preleptotene spermatocytes differentiated from type B spermatogonia residing at the basal compartment must traverse the blood-testis barrier (BTB) to enter the adluminal compartment to prepare for meiosis at Stage VIII of the epithelial cycle, a process also accompanied by the release of sperm at spermiation. These cellular events that take place at the opposite ends of the epithelium are co-ordinated by a functional axis designated the apical ectoplasmic specialization (ES)-BTB-basement membrane. However, the regulatory molecules that co-ordinate cellular events in this axis are not known. METHODS Literature was searched at http://www.pubmed.org and http://scholar.google.com to identify published findings regarding intercellular adhesion molecules (ICAMs) and the regulation of this axis. RESULTS Members of the ICAM family, namely ICAM-1 and ICAM-2, and the biologically active soluble ICAM-1 (sICAM-1) are the likely regulatory molecules that co-ordinate these events. sICAM-1 and ICAM-1 have antagonistic effects on the Sertoli cell tight junction-permeability barrier, involved in Sertoli cell BTB restructuring, whereas ICAM-2 is restricted to the apical ES, regulating spermatid adhesion during the epithelial cycle. Studies in other epithelia/endothelia on the role of the ICAM family in regulating cell movement are discussed and this information has been evaluated and integrated into studies of these proteins in the testis to create a hypothetical model, depicting how ICAMs regulate junction restructuring events during spermatogenesis. CONCLUSIONS ICAMs are crucial regulatory molecules of spermatogenesis. The proposed hypothetical model serves as a framework in designing functional experiments for future studies.
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Affiliation(s)
- Xiang Xiao
- 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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Xiao X, Mruk DD, Cheng FL, Cheng CY. C-Src and c-Yes are two unlikely partners of spermatogenesis and their roles in blood-testis barrier dynamics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 763:295-317. [PMID: 23397631 DOI: 10.1007/978-1-4614-4711-5_15] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Src family kinases (SFKs), in particular c-Src and c-Yes, are nonreceptor protein tyrosine kinases that mediate integrin signaling at focal adhesion complex at the cell-extracellular matrix interface to regulate cell adhesion, cell cycle progression, cell survival, proliferation and differentiation, most notably in cancer cells during tumorigenesis and metastasis. Interestingly, recent studies have shown that these two proto-oncogenes are integrated components of the stem cell niche and the cell-cell actin-based anchoring junction known as ectoplasmic specialization (ES) at the: (1) Sertoli cell-spermatid interface known as apical ES and (2) Sertoli-Sertoli cell interface known as basal ES which together with tight junctions (TJ), gap junctions and desmosomes constitute the blood-testis barrier (BTB). At the stem cell niche, these SFKs regulate spermatogonial stem cell (SSC) renewal to maintain the proper population of SSC/spermatogonia for spermatogenesis. At the apical ES and the BTB, c-Src and c-Yes confer cell adhesion either by maintaining the proper phosphorylation status of integral membrane proteins at the site which in turn regulates protein-protein interactions between integral membrane proteins and their adaptors, or by facilitating androgen action on spermatogenesis via a nongenomic pathway which also modulates cell adhesion in the seminiferous epithelium. Herein, we critically evaluate recent findings in the field regarding the roles of these two unlikely partners of spermatogenesis. We also propose a hypothetical model on the mechanistic functions of c-Src and c-Yes in spermatogenesis so that functional experiments can be designed in future studies.
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Affiliation(s)
- Xiang Xiao
- Center for Biomedical Research, Population Council, New York New York, USA
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Xiao X, Cheng CY, Mruk DD. Intercellular adhesion molecule-2 is involved in apical ectoplasmic specialization dynamics during spermatogenesis in the rat. J Endocrinol 2013; 216:73-86. [PMID: 23097088 PMCID: PMC3535886 DOI: 10.1530/joe-12-0434] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In this study, we investigated the role of intercellular adhesion molecule-2 (ICAM2) in the testis. ICAM2 is a cell adhesion protein having important roles in cell migration, especially during inflammation when leukocytes cross the endothelium. Herein, we showed ICAM2 to be expressed by germ and Sertoli cells in the rat testis. When a monospecific antibody was used for immunolocalization experiments, ICAM2 was found to surround the heads of elongating/elongated spermatids in all stages of the seminiferous epithelial cycle. To determine whether ICAM2 is a constituent of apical ectoplasmic specialization (ES), co-immunoprecipitation and dual immunofluorescence staining were performed. Interestingly, ICAM2 was found to associate with β1-integrin, nectin-3, afadin, Src, proline-rich tyrosine kinase 2, annexin II, and actin. Following CdCl₂ treatment, ICAM2 was found to be upregulated during restructuring of the seminiferous epithelium, with round spermatids becoming increasingly immunoreactive for ICAM2 by 6-16 h. Interestingly, there was a loss in the binding of ICAM2 to actin during CdCl₂-induced germ cell loss, suggesting that a loss of ICAM2-actin interactions might have facilitated junction restructuring. Taken collectively, these results illustrate that ICAM2 plays an important role in apical ES dynamics during spermatogenesis.
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Su L, Mruk DD, Cheng CY. Regulation of the blood-testis barrier by coxsackievirus and adenovirus receptor. Am J Physiol Cell Physiol 2012; 303:C843-53. [PMID: 22875787 DOI: 10.1152/ajpcell.00218.2012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The blood-testis barrier (BTB) divides the seminiferous epithelium into the basal and the adluminal compartment. It restricts paracellular diffusion of molecules between Sertoli cells, confers cell polarity, and creates a unique microenvironment in the adluminal compartment for spermatid development. However, it undergoes restructuring during the epithelial cycle so that preleptotene spermatocytes differentiated from type B spermatogonia residing in the basal compartment can traverse the BTB at stage VIII of the cycle, while the immunological barrier is maintained. Herein, coxsackievirus and adenovirus receptor (CAR), a tight junction (TJ) integral membrane protein in the testis and multiple epithelia and endothelia, was found to act as a regulatory protein at the BTB, besides serving as a structural adhesion protein. RNAi-mediated knockdown of CAR in a Sertoli cell epithelium with an established TJ-permeability barrier that mimicked the BTB in vivo resulted in a disruption of the TJ barrier and an increase in endocytosis of the TJ-protein occludin. Furthermore, such an enhancement in occludin endocytosis was accompanied by a downregulation of Thr-phosphorylation in occludin and an increase in the association of endocytosed occludin with early endosome antigen-1. These findings were confirmed by overexpressing CAR in Sertoli cells, which was found to "tighten" the Sertoli cell TJ barrier, promoting BTB function. These findings support the emerging concept that CAR is not only a structural protein, it is involved in conferring the phosphorylation status of other adhesion proteins at the BTB (e.g., occludin) possibly mediated via its structural interactions with nonreceptor protein kinases, thereby modulating endocytic vesicle-mediated protein trafficking.
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Affiliation(s)
- Linlin Su
- Center for Biomedical Research, Population Council, New York, New York 10065, USA
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Su W, Mruk DD, Cheng CY. Filamin A: A regulator of blood-testis barrier assembly during post-natal development. SPERMATOGENESIS 2012; 2:73-78. [PMID: 22670216 PMCID: PMC3364794 DOI: 10.4161/spmg.20223] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Filamins are a family of actin-binding proteins composed of filamin A, B and C. Besides of their ability to induce perpendicular branching of F-actin filaments via their actin binding domains near the N-terminus, filamins can regulate multiple cellular functions because of their unique ability to recruit more than 90 protein binding partners to their primary sequences which are having highly diversified cellular functions. However, this family of proteins has not been examined in the testis until recently. Herein, we highlight recent findings in the field regarding the role of these proteins in cell epithelia, and based on recent data in the testis regarding their role on spermatogenesis, this review provides the basis for future functional studies.
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Affiliation(s)
- Wenhui Su
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; The Population Council; New York, NY USA
- Department of Biochemistry and Molecular Biology; China Medical University; Shen Yang, China
| | - Dolores D. Mruk
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; The Population Council; New York, NY USA
| | - 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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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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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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Cheng CY, Wong EWP, Lie PPY, Mruk DD, Xiao X, Li MWM, Lui WY, Lee WM. Polarity proteins and actin regulatory proteins are unlikely partners that regulate cell adhesion in the seminiferous epithelium during spermatogenesis. Histol Histopathol 2011; 26:1465-74. [PMID: 21938683 PMCID: PMC4059515 DOI: 10.14670/hh-26.1465] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In mammalian testis, spermatogenesis takes place in the seminiferous epithelium of the seminiferous tubule, which is composed of a series of cellular events. These include: (i) spermatogonial stem cell (SSC) renewal via mitosis and differentiation of SSC to spermatogenia, (ii) meiosis, (iii) spermiogenesis, and (iv) spermiation. Throughout these events, developing germ cells remain adhered to the Sertoli cell in the seminiferous epithelium amidst extensive cellular, biochemical, molecular and morphological changes to obtain structural support and nourishment. These events are coordinated via signal transduction at the cell-cell interface through cell junctions, illustrating the significance of cell junctions and adhesion in spermatogenesis. Additionally, developing germ cells migrate progressively across the seminiferous epithelium from the stem cell niche, which is located in the basal compartment near the basement membrane of the tunica propria adjacent to the interstitium. Recent studies have shown that some apparently unrelated proteins, such as polarity proteins and actin regulatory proteins, are in fact working in concert and synergistically to coordinate the continuous cyclic changes of adhesion at the Sertoli-Sertoli and Sertoli-germ cell interface in the seminiferous epithelium during the epithelial cycle of spermatogenesis, such that developing germ cells remain attached to the Sertoli cell in the epithelium while they alter in cell shape and migrate across the epithelium. In this review, we highlight the physiological significance of endocytic vesicle-mediated protein trafficking events under the influence of polarity and actin regulatory proteins in conferring cyclic events of cell adhesion and de-adhesion. Furthermore, these recent findings have unraveled some unexpected molecules to be targeted for male contraceptive development, which are also targets of toxicant-induced male reproductive dysfunction.
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Affiliation(s)
- C Y Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Population Council, New York, USA.
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Cheng CY, Lie PP, Wong EW, Mruk DD, Silvestrini B. Adjudin disrupts spermatogenesis via the action of some unlikely partners: Eps8, Arp2/3 complex, drebrin E, PAR6 and 14-3-3. SPERMATOGENESIS 2011; 1:291-297. [PMID: 22332112 DOI: 10.4161/spmg.1.4.18393] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 10/10/2011] [Accepted: 10/11/2011] [Indexed: 02/08/2023]
Abstract
Adjudin, 1-(2,4-dichlorobenzyl)-1H-indazole-3-carbohydrazide (formerly called AF-2364), is a potent analog of lonidamine [1-(2,4-dichlorobenzyl)-1H-indazole-3-carboxylic acid] known to disrupt germ cell adhesion, most notably elongating and elongated spermatids, in the seminiferous epithelium of adult rat testes and thus, leads to infertility in rats. Since the population of spermatogonia and spermatogonial stem cells (SSCs) in the seminiferous tubules is not significantly reduced by the treatment of rats with adjudin, adjudin-induced infertility is highly reversible, which enables reinitiation of spermatogenesis and germ cell re-population of the voided seminiferous epithelium. Furthermore, adjudin appears to exert its effects at the testis-specific atypical adherens junction (AJ) type known as ectoplasmic specialization (ES), most notably the apical ES at the Sertoli cell-spermatid interface. Thus, the hypothalamic-pituitary-gonadal axis is not unaffected and systemic side-effects are minimal. This also makes adjudin a potential candidate for male contraceptive development. Herein, we critically evaluate recent findings in the field and provide an updated model regarding the mechanism underlying adjudin-induced apical ES disruption. In short, adjudin targets actin filament bundles at the apical ES, the hallmark ultrastructure of this testis-specific junction type not found in any other epithelia/endothelia in mammals, by suppressing the expression of Eps8 (epidermal growth factor receptor pathway substrate 8), an actin capping protein that also plays a role in actin bundling, so that actin filament bundles can no longer be maintained at the apical ES. This is concomitant with a mis-localization of Arp3 (actin-related protein 3, a component of the Arp2/3 complex that induces actin nucleation/branching) recruited by drebrin E, causing "unwanted" actin branching, further destabilizing actin filament bundles at the apical ES. Additionally, adjudin blocks the expression of PAR6 (partitioning defective protein 6) and 14-3-3 (also known as PAR5) considerably at the apical ES, disrupting the homeostasis of endocytic vesicle-mediated protein trafficking, which in turn leads to an increase in protein endocytosis. The net result of these changes destabilizes cell adhesion and induces degeneration of the apical ES, causing premature release of spermatids, mimicking spermiation.
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Affiliation(s)
- C Yan Cheng
- Center for Biomedical Research; The Population Council; New York, NY USA
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Regulation of spermiogenesis, spermiation and blood-testis barrier dynamics: novel insights from studies on Eps8 and Arp3. Biochem J 2011; 435:553-62. [PMID: 21486226 DOI: 10.1042/bj20102121] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Spermiogenesis in the mammalian testis is the most critical post-meiotic developmental event occurring during spermatogenesis in which haploid spermatids undergo extensive cellular, molecular and morphological changes to form spermatozoa. Spermatozoa are then released from the seminiferous epithelium at spermiation. At the same time, the BTB (blood-testis barrier) undergoes restructuring to facilitate the transit of preleptotene spermatocytes from the basal to the apical compartment. Thus meiotic divisions take place behind the BTB in the apical compartment to form spermatids. These germ cells enter spermiogenesis to transform into elongating spermatids and then into spermatozoa to replace those that were released in the previous cycle. However, the mole-cular regulators that control spermiogenesis, in particular the dynamic changes that occur at the Sertoli cell-spermatid interface and at the BTB, are not entirely known. This is largely due to the lack of suitable animal models which can be used to study these events. During the course of our investigation to develop adjudin [1-(2,4-dichlorobenzyl)-1H-indazole-3-carbohydrazide] as a potential male contraceptive, this drug was shown to 'accelerate' spermiation by inducing the release of premature spermatids from the epithelium. Using this model, we have identified several molecules that are crucial in regulating the actin filament network and the unique adhesion protein complex at the Sertoli cell-spermatid interface known as the apical ES (ectoplasmic specialization). In the present review, we critically evaluate these and other findings in the literature as they relate to the restricted temporal and spatial expression of two actin regulatory proteins, namely Eps8 (epidermal growth factor receptor pathway substrate 8) and Arp3 (actin-related protein 3), which regulate these events.
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Cheng YH, Wong EW, Cheng CY. Cancer/testis (CT) antigens, carcinogenesis and spermatogenesis. SPERMATOGENESIS 2011; 1:209-220. [PMID: 22319669 PMCID: PMC3271663 DOI: 10.4161/spmg.1.3.17990] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Revised: 09/01/2011] [Accepted: 09/05/2011] [Indexed: 02/07/2023]
Abstract
During spermatogenesis, spermatogonial stem cells, undifferentiated and differentiated spermatogonia, spermatocytes, spermatids and spermatozoa all express specific antigens, yet the functions of many of these antigens remain unexplored. Studies in the past three decades have shown that many of these transiently expressed genes in developing germ cells are proto-oncogenes and oncogenes, which are expressed only in the testis and various types of cancers in humans and rodents. As such, these antigens are designated cancer/testis antigens (CT antigens). Since the early 1980s, about 70 families of CT antigens have been identified with over 140 members are known to date. Due to their restricted expression in the testis and in various tumors in humans, they have been used as the target of immunotherapy. Multiple clinical trials at different phases are now being conducted with some promising results. Interestingly, in a significant number of cancer patients, antibodies against some of these CT antigens were detected in their sera. However, antibodies against these CT antigens in humans under normal physiological conditions have yet to be reported even though many of these antigens are residing outside of the blood-testis barrier (BTB), such as in the basal compartment of the seminiferous epithelium and in the stem cell niche in the testis. In this review, we summarize latest findings in the field regarding several selected CT antigens which may be intimately related to spermatogenesis due to their unusual restricted expression during different discrete events of spermatogenesis, such as cell cycle progression, meiosis and spermiogenesis. This information should be helpful to investigators in the field to study the roles of these oncogenes in spermatogenesis.
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Affiliation(s)
- Yan-Ho Cheng
- Center for Biomedical Research; The Population Council; New York, NY USA
- Richmond University Medical Center; Staten Island, NY USA
| | - Elissa Wp Wong
- Center for Biomedical Research; The Population Council; New York, NY USA
| | - C Yan Cheng
- 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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Mok KW, Mruk DD, Lie PPY, Lui WY, Cheng CY. Adjudin, a potential male contraceptive, exerts its effects locally in the seminiferous epithelium of mammalian testes. Reproduction 2011; 141:571-80. [PMID: 21307270 DOI: 10.1530/rep-10-0464] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Adjudin is a derivative of 1H-indazole-3-carboxylic acid that was shown to have potent anti-spermatogenic activity in rats, rabbits, and dogs. It exerts its effects most notably locally in the apical compartment of the seminiferous epithelium, behind the blood-testis barrier, by disrupting adhesion of germ cells, most notably spermatids to the Sertoli cells, thereby inducing release of immature spermatids from the epithelium that leads to infertility. After adjudin is metabolized, the remaining spermatogonial stem cells and spermatogonia repopulate the seminiferous epithelium gradually via spermatogonial self-renewal and differentiation, to be followed by meiosis and spermiogenesis, and thus fertility rebounds. Recent studies in rats have demonstrated unequivocally that the primary and initial cellular target of adjudin in the testis is the apical ectoplasmic specialization, a testis-specific anchoring junction type restricted to the interface between Sertoli cells and elongating spermatids (from step 8 to 19 spermatids). In this review, we highlight some of the recent advances and obstacles regarding the possible use of adjudin as a male contraceptive.
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Affiliation(s)
- Ka-Wai Mok
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York, New York 10065, 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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