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Schulz B, Schumacher V, Ngezahayo A, Maier-Begandt D, Schadzek N, Wilhelm J, Weidner W, Pilatz A, Fietz D, Kliesch S, Schnepel N, Hambruch N, Rode K, Langeheine M, Brehm R. Analysis of connexin 43, connexin 45 and N-cadherin in the human sertoli cell line FS1 and the human seminoma-like cell line TCam-2 in comparison with human testicular biopsies. BMC Cancer 2023; 23:232. [PMID: 36899312 PMCID: PMC10007848 DOI: 10.1186/s12885-023-10696-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 03/01/2023] [Indexed: 03/12/2023] Open
Abstract
BACKGROUND Germ cell tumors are relatively common in young men. They derive from a non-invasive precursor, called germ cell neoplasia in situ, but the exact pathogenesis is still unknown. Thus, further understanding provides the basis for diagnostics, prognostics and therapy and is therefore paramount. A recently developed cell culture model consisting of human FS1 Sertoli cells and human TCam-2 seminoma-like cells offers new opportunities for research on seminoma. Since junctional proteins within the seminiferous epithelium are involved in cell organization, differentiation and proliferation, they represent interesting candidates for investigations on intercellular adhesion and communication in context with neoplastic progression. METHODS FS1 and TCam-2 cells were characterized regarding gap-junction-related connexin 43 (Cx43) and connexin 45 (Cx45), and adherens-junction-related N-cadherin using microarray, PCR, Western blot, immunocytochemistry and immunofluorescence. Results were compared to human testicular biopsies at different stages of seminoma development via immunohistochemistry to confirm the cell lines' representativeness. Furthermore, dye-transfer measurements were performed to investigate functional cell coupling. RESULTS Cx43, Cx45 and N-cadherin mRNA and protein were generally detectable in both cell lines via qualitative RT-PCR and Western blot. Immunocytochemistry and immunofluorescence revealed a mainly membrane-associated expression of N-cadherin in both cell lines, but gene expression values were higher in FS1 cells. Cx43 expression was also membrane-associated in FS1 cells but barely detectable in TCam-2 cells. Accordingly, a high gene expression value of Cx43 was measured for FS1 and a low value for TCam-2 cells. Cx45 was primary located in the cytoplasm of FS1 and TCam-2 cells and revealed similar low to medium gene expression values in both cell lines. Overall, results were comparable with corresponding biopsies. Additionally, both FS1 and TCam-2 cells showed dye diffusion into neighboring cells. CONCLUSION The junctional proteins Cx43, Cx45 and N-cadherin are expressed in FS1 and TCam-2 cells at mRNA and/or protein level in different amounts and localizations, and cells of both lines are functionally coupled among each other. Concerning the expression of these junctional proteins, FS1 and TCam-2 cells are largely representative for Sertoli and seminoma cells, respectively. Thus, these results provide the basis for further coculture experiments evaluating the role of junctional proteins in context with seminoma progression.
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Affiliation(s)
- Birte Schulz
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.
| | - Valérie Schumacher
- Department of Urology and Medicine, Boston Children's Hospital, Boston, MA, USA.,Department of Surgery and Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Anaclet Ngezahayo
- Department of Cell Physiology and Biophysics, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hannover, Germany.,Center for Systems Neuroscience Hannover, University of Veterinary Medicine Hannover Foundation, Hannover, Germany
| | - Daniela Maier-Begandt
- Department of Cell Physiology and Biophysics, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hannover, Germany
| | - Nadine Schadzek
- Department of Cell Biology, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hannover, Germany
| | - Jochen Wilhelm
- Institute for Lung Health, Justus Liebig University Giessen, Giessen, Germany.,Universities of Giessen and Marburg Lung Center, Member of the German Center for Lung Research, Justus Liebig University Giessen, Giessen, Germany.,The Cardiopulmonary Institute, Justus Liebig University Giessen, Giessen, Germany
| | - Wolfgang Weidner
- Department of Urology, Pediatric Urology and Andrology, Justus Liebig University Giessen, Giessen, Germany
| | - Adrian Pilatz
- Department of Urology, Pediatric Urology and Andrology, Justus Liebig University Giessen, Giessen, Germany
| | - Daniela Fietz
- Department of Veterinary Anatomy, Histology and Embryology, Justus Liebig University Giessen, Giessen, Germany
| | - Sabine Kliesch
- Centre of Andrology and Reproductive Medicine, University of Muenster, Muenster, Germany
| | - Nadine Schnepel
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Nina Hambruch
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Kristina Rode
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Marion Langeheine
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Ralph Brehm
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
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NGF regulates sertoli cell growth and prevents LPS-induced junction protein damage via PI3K/AKT/NFκB signaling. Theriogenology 2023; 195:138-148. [DOI: 10.1016/j.theriogenology.2022.10.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 09/22/2022] [Accepted: 10/13/2022] [Indexed: 11/05/2022]
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3
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The Expression of Connexin 26 Regulates the Radiosensitivity of Hepatocellular Carcinoma Cells through a Mitogen-Activated Protein Kinases Signal Pathway. Int J Mol Sci 2022; 23:ijms232314644. [PMID: 36498978 PMCID: PMC9740976 DOI: 10.3390/ijms232314644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/09/2022] [Accepted: 11/21/2022] [Indexed: 11/25/2022] Open
Abstract
Connexin 26 (Cx26) is a protein that constitutes a gap junction and is widely expressed in the liver. Abnormal expression of Cx26 is one of the important mechanisms of liver cancer, and is closely related to the transmission of radiation damage signals between cells. In the present study, we investigated the radiosensitivity of hepatocellular carcinoma (HCC) cells HepG2, with low expression of Cx26, and SK-hep-1, with high expression of Cx26 after X-ray irradiation. The cell survival, micronucleus formation and protein expressions of the mitogen-activated protein kinases (MAPK) signaling pathway were detected. The expression level of Cx26 could affect the radiosensitivity of liver cancer cells by affecting the phosphorylation of p38 and ERK proteins and regulating the expression of downstream NF-κB. Cell lines with knock-out and overexpression of Cx26 were also built to confirm the findings. Our results suggested that Cx26 might play an important role in the radiosensitivity of liver cancer and could be a potential target for clinical radiotherapy of liver cancer.
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Sato A, da Fonseca IIM, Nagamine MK, de Toledo GF, Olio R, Hernandez-Blazquez FJ, Yano T, Yeh ES, Dagli MLZ. Effects of Alpha-Connexin Carboxyl-Terminal Peptide (aCT1) and Bowman-Birk Protease Inhibitor (BBI) on Canine Oral Mucosal Melanoma (OMM) Cells. Front Vet Sci 2021; 8:670451. [PMID: 34179163 PMCID: PMC8222509 DOI: 10.3389/fvets.2021.670451] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 05/11/2021] [Indexed: 11/22/2022] Open
Abstract
Oral mucosal melanomas (OMM) are aggressive cancers in dogs, and are good models for human OMM. Gap junctions are composed of connexin units, which may have altered expression patterns and/or subcellular localization in cancer cells. Cell-to-cell communication by gap junctions is often impaired in cancer cells, including in melanomas. Meanwhile, the upregulated expression of the gap junction protein connexin 43 (Cx43) inhibits melanoma progression. The α-connexin carboxyl-terminal (aCT1) peptide reportedly maintains Cx43 expression and cell-cell communication in human mammary cells and increases the communication activity through gap junctions in functional assays, therefore causing decreased cell proliferation. The Bowman-Birk protease inhibitor (BBI), a component of soybeans, induces Cx43 expression in several tumor cells as a trypsin–chymotrypsin inhibition function, with antineoplastic effects. This study investigated the effect of aCT1 peptide and BBI treatment, alone or in combination, on TLM1 canine melanoma cell viability. Cell viability after treatment with aCT1, the reverse sequence peptide (R-pep), and/or BBI for 5 days was analyzed by PrestoBlue assay. Immunofluorescence was used to observe Cx43 localization and expression. aCT1 (200 μM) alone did not significantly decrease cell viability in TLM1 cells, whereas BBI (400 μg/ml) alone significantly decreased the TLM1 viability. Combined treatment with both aCT1 (200 μM) and BBI (400 μg/ml) significantly decreased cell viability in TLM1 cells. Cx43 expression, as identified by immunostainings in TLM1 cells, was increased in the cell membrane after the combination treatment with BBI and aCT1. This dual treatment can be combined to achieve the anticancer activity, possibly by increasing Cx 43 expression and affecting Cx43 migration to the cell membrane. In conclusion, a treatment strategy targeting Cx43 with BBI and aCT1 may possibly lead to new effective therapies for canine OMM.
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Affiliation(s)
- Ayami Sato
- School of Veterinary Medicine and Animal Science of the University of São Paulo, São Paulo, Brazil.,Institute of Life Innovation Studies, Toyo University, Tokyo, Japan
| | | | - Márcia Kazumi Nagamine
- School of Veterinary Medicine and Animal Science of the University of São Paulo, São Paulo, Brazil
| | | | - Rennan Olio
- School of Veterinary Medicine and Animal Science of the University of São Paulo, São Paulo, Brazil
| | | | - Tomohiro Yano
- Institute of Life Innovation Studies, Toyo University, Tokyo, Japan
| | - Elizabeth Shinmay Yeh
- Department of Pharmacology and Toxicology, Simon Comprehensive Cancer Center, School of Medicine, Indiana University, Indianapolis, IN, United States
| | - Maria Lucia Zaidan Dagli
- School of Veterinary Medicine and Animal Science of the University of São Paulo, São Paulo, Brazil
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5
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Ramisz G, Turek W, Chmurska-Gasowska M, Rak A, Pietsch-Fulbiszewska A, Galuszka A, Kotula-Balak M, Tarasiuk K. Senescence and adiponectin signaling - Studies in canine testis. Ann Anat 2020; 234:151606. [PMID: 33096233 DOI: 10.1016/j.aanat.2020.151606] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 08/24/2020] [Accepted: 09/11/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND The meaning of senescence for tissue physiological and pathological conditions is poorly known. Based on initial reports especially proteins and mechanisms that regulate this process are necessary to be determinate. METHODS The main aim of the study was to investigate the presence of senescent cells in canine testicular tissue (mixed breed testes; n = 60) in relation to adiponectin signaling. In detail, new information on the senescence cell number, as well as senescence and adiponectin signaling mechanisms in cryptorchid and germ cell tumor testes were provided with the use of immunohistochemical and colorimetric analyses. RESULTS Comparison of immunohistochemical results, in cryptorchid and tumor testes revealed increased number of senescent cells (p16 and γH2AX markers). Increased expression of adiponectin and adiponectin receptor 1, as well as extracellular signal-activated kinase (ERK1/2) in pathological testes were detected. In addition, decreased cholesterol and increased testosterone levels in tumor testis were found. CONCLUSION The present study is the first to demonstrate the presence as well as the differences that exist in senecent cell number in mixed breed dog testes with cryptorchidism and germ cell tumor. Altered expression of adiponectin signaling and ERK1/2 signaling pathways together with altered cholesterol and testosterone levels reflect important senescence role in disturbed functions of canine testis. Moreover, the application of studied here senescence regulating molecules for detection and prevention against pathologies of the male gonad should be furtherly considered.
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Affiliation(s)
- Grzegorz Ramisz
- University Centre of Veterinary Medicine JU-UA, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland
| | - Wiktor Turek
- University Centre of Veterinary Medicine JU-UA, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland
| | - Maria Chmurska-Gasowska
- University Centre of Veterinary Medicine JU-UA, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland
| | - Agnieszka Rak
- Department of Physiology and Toxicology of Reproduction, Institute of Zoology and Biomedical Research, Jagiellonian University in Krakow, Gronostajowa 9, 30-387 Krakow, Poland
| | - Agnieszka Pietsch-Fulbiszewska
- University Centre of Veterinary Medicine JU-UA, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland
| | - Anna Galuszka
- University Centre of Veterinary Medicine JU-UA, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland
| | - Malgorzata Kotula-Balak
- University Centre of Veterinary Medicine JU-UA, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland.
| | - Kazimierz Tarasiuk
- University Centre of Veterinary Medicine JU-UA, University of Agriculture in Krakow, Mickiewicza 24/28, 30-059 Krakow, Poland
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Expression of claudin-11 in canine prepubertal testes, and in canine adult testes showing normal spermatogenesis, impaired spermatogenesis, or testicular neoplasia. Theriogenology 2020; 148:122-131. [PMID: 32171971 DOI: 10.1016/j.theriogenology.2020.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 03/01/2020] [Accepted: 03/02/2020] [Indexed: 01/05/2023]
Abstract
The blood-testis barrier (BTB) consists of different cell-to-cell connections, including tight junction proteins like claudin-11 (CLDN11). For dogs, only limited data is published dealing with these proteins in general. Therefore, their physiological relevance, their postnatal expression, and their distribution pattern in pathological conditions, e.g. in altered spermatogenesis and testicular neoplasia were assessed. Canine testes from routine castrations, and those sent in for diagnostic purposes were investigated. Based on morphological evaluation, the dogs and testes were divided into groups: (1) dogs with normal spermatogenesis, (2) four months old prepubertal dogs, (3) intratubular seminoma, (4) diffuse seminoma, (5) Sertoli cell tumours (SCT), (6) Leydig cell tumours (LCT), and (7) dogs with impaired spermatogenesis (e.g. mixed atrophy). In order to examine possible alterations of the BTB components, immunohistochemistry (IHC) and immunofluorescence using a commercial antibody against CLDN11 was performed. Sertoli cell (SC) nuclei (SOX9) and peritubular myoid cells (smooth-muscle-actin, SMA) were also assessed using IHC. Additionally, semi-quantitative Western-blot (WB) and RT-PCR analyses of CLDN11 were conducted. In tubules with normal spermatogenesis, IHC of CLDN11 revealed a basolateral staining at BTB localisation. In prepubertal cords, CLDN11 was diffusely expressed along the cytoplasmic extensions of SCs supposing that the BTB was neither built up nor functional, yet. A shift from weakly expressed CLDN11 between/in residual SCs in intratubular seminoma to only small CLDN11 immunopositive stained spots in the cytoplasm of remaining SOX9-positive SCs in diffuse seminoma was detectable. Reduction or even loss of CLDN11 expression in diffuse seminoma was confirmed using RT-PCR and WB analyses, thus indicating that in seminoma, CLDN11 was downregulated at transcriptional level and completely lost its sealing function. Basal SCs in SCT still showed a CLDN11/SOX9 co-localisation, suggesting that luminal neoplastic SCs undergo de-differentiation during tumour progression. In LCT, no CLDN11 was detectable. Dogs with mixed atrophy showed an upregulation of CLDN11 in tubules with spermatogenic arrest on mRNA and protein level, leading to the conclusion that within these tubules regulatory mechanisms lost their equilibrium. For the first time, the spatial expression of CLDN11 in prepubertal canine testis, impaired spermatogenesis, intratubular seminoma and its absence in diffuse seminoma and LCT was shown. Since altered CLDN11 levels could be part of adaptive mechanisms to modify BTB integrity, further functional investigations to characterize the canine BTB need to be conducted.
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7
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Hollenbach J, Jung K, Noelke J, Gasse H, Pfarrer C, Koy M, Brehm R. Loss of connexin43 in murine Sertoli cells and its effect on blood-testis barrier formation and dynamics. PLoS One 2018; 13:e0198100. [PMID: 29856785 PMCID: PMC5983412 DOI: 10.1371/journal.pone.0198100] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 05/14/2018] [Indexed: 12/11/2022] Open
Abstract
Connexin43 (Cx43) is the predominant testicular gap junction protein and in cases of impaired spermatogenesis, Cx43 expression has been shown to be altered in several mammals. Amongst other functions, Cx43 is supposed to regulate junction formation of the blood-testis barrier (BTB). The aim of the present study was to investigate the expression pattern of different tight junction (TJ) proteins of the murine BTB using SC-specific Cx43 knockout mice (SCCx43KO). Adult homozygous male SCCx43KO mice (SCCx43KO-/-) predominantly show an arrest of spermatogenesis and SC-only tubules that might have been caused by an altered BTB assembly, composition or regulation. TJ molecules claudin-3, -5 and -11 were examined in adult wild type (WT) and SCCx43KO-/- mice using immunohistochemistry (IHC) and quantitative real-time PCR (qRT-PCR). In this context, investigation of single tubules with residual spermatogenesis in SCCx43KO-/- mice was particularly interesting to identify a potential Cx43-independent influence of germ cells (GC) on BTB composition and dynamics. In tubules without residual spermatogenesis, a diffuse cytoplasmic distribution pattern for claudin-11 protein could be demonstrated in mutant mice. Nevertheless, claudin-11 seems to form functional TJ. Claudin-3 and -5 could not be detected immunohistochemically in the seminiferous epithelium of those tubules. Correspondingly, claudin-3 and -5 mRNA expression was decreased, providing evidence of generally impaired BTB dynamics in adult KO mice. Observations of tubules with residual spermatogenesis suggested a Cx43-independent regulation of TJ proteins by GC populations. To determine initial BTB formation in peripubertal SCCx43KO-/- mice, immunohistochemical staining and qRT-PCR of claudin-11 were carried out in adolescent SCCx43KO-/- and WT mice. Additionally, BTB integrity was functionally analysed using a hypertonic glucose fixative. These analyses revealed that SCCx43KO-/- mice formed an intact BTB during puberty in the same time period as WT mice, which however seemed to be accelerated.
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Affiliation(s)
- Julia Hollenbach
- Institute for Anatomy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Klaus Jung
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Joanna Noelke
- Institute for Anatomy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Hagen Gasse
- Institute for Anatomy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Christiane Pfarrer
- Institute for Anatomy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Mirja Koy
- Institute for Immunology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Ralph Brehm
- Institute for Anatomy, University of Veterinary Medicine Hannover, Hannover, Germany
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Wu DP, Lin TY, Bai LR, Huang JL, Zhou Y, Zhou N, Zhong SL, Gao S, Yin XX. Enhanced phototoxicity of photodynamic treatment by Cx26-composed GJIC via ROS-, calcium- and lipid peroxide-mediated pathways. JOURNAL OF BIOPHOTONICS 2017; 10:1586-1596. [PMID: 28417552 DOI: 10.1002/jbio.201600255] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 12/11/2016] [Accepted: 01/12/2017] [Indexed: 06/07/2023]
Abstract
In spite of the promising initial treatment responses presented by photodynamic therapy (PDT), 5-year recurrence rates remain high level. Therefore, improvement in the efficacy of PDT is needed. There are reports showing that connexin(Cx) 26-composed gap junctional intercellular communication (GJIC) enhances the intercellular propagation of "death signal", thereby increasing chemotherapeutic cytotoxicity. However, it is unclear whether Cx26-formed GJIC has an effect on PDT phototoxicity. The results in the present study showed that Cx26-composed GJ formation at high density enhances the phototoxicity of Photofrin-PDT. When the Cx26 is not expressed or Cx26 channels are blocked, the phototoxicity in high-density cultures substantially reduces, indicating that the enhanced PDT phototoxicity at high density is mediated by Cx26-composed GJIC. The GJIC-mediated increase in PDT phototoxicity was associated with ROS, calcium and lipid peroxide-mediated stress signaling pathways. The work presents the ability of Cx26-composed GJIC to enhance the sensitivity of malignant cells to PDT, and indicates that maintenance or increase of Cx26-formed GJIC may be a profitable strategy towards the enhancement of PDT therapeutic efficiency. Picture: The survival response of Photofrin-PDT in Dox-treated (Cx26 expressing, GJ-formed) and Dox-untreated cells (Cx26 non-expressing, GJ-unformed) at high-cell density condition.
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Affiliation(s)
- Deng-Pan Wu
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Pharmacy School of Xuzhou Medical University, Xuzhou City, Jiangsu Province, 221004, P.R. China
- Department of Pharmacology, Pharmacy School of Xuzhou Medical University, 221004, Xuzhou City, Jiangsu Province, P.R. China
| | - Tian-Yu Lin
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Pharmacy School of Xuzhou Medical University, Xuzhou City, Jiangsu Province, 221004, P.R. China
| | - Li-Ru Bai
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Pharmacy School of Xuzhou Medical University, Xuzhou City, Jiangsu Province, 221004, P.R. China
| | - Jin-Lan Huang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Pharmacy School of Xuzhou Medical University, Xuzhou City, Jiangsu Province, 221004, P.R. China
- Department of Pharmacology, Pharmacy School of Xuzhou Medical University, 221004, Xuzhou City, Jiangsu Province, P.R. China
| | - Yan Zhou
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Pharmacy School of Xuzhou Medical University, Xuzhou City, Jiangsu Province, 221004, P.R. China
| | - Nan Zhou
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Pharmacy School of Xuzhou Medical University, Xuzhou City, Jiangsu Province, 221004, P.R. China
| | - Sheng-Lei Zhong
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Pharmacy School of Xuzhou Medical University, Xuzhou City, Jiangsu Province, 221004, P.R. China
| | - Shan Gao
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Pharmacy School of Xuzhou Medical University, Xuzhou City, Jiangsu Province, 221004, P.R. China
| | - Xiao-Xing Yin
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Pharmacy School of Xuzhou Medical University, Xuzhou City, Jiangsu Province, 221004, P.R. China
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9
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Rode K, Sieme H, Otzen H, Schwennen C, Lüpke M, Richterich P, Schrimpf R, Distl O, Brehm R. Effects of Repeated Testicular Biopsies in Adult Warmblood Stallions and Their Diagnostic Potential. J Equine Vet Sci 2016. [DOI: 10.1016/j.jevs.2016.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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10
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Wu D, Fan L, Xu C, Liu Z, Zhang Y, Liu L, Wang Q, Tao L. GJIC Enhances the phototoxicity of photofrin-mediated photodynamic treatment by the mechanisms related with ROS and Calcium pathways. JOURNAL OF BIOPHOTONICS 2015; 8:764-774. [PMID: 25597481 DOI: 10.1002/jbio.201400131] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 11/28/2014] [Accepted: 11/30/2014] [Indexed: 06/04/2023]
Abstract
Despite initially positive responses, recurrences after Photodynamic treatment (PDT) can occur and there is need for improvement in the effectiveness of PDT. Our study uniquely showed that there was a significantly gap junctional intercellular communication (GJIC)-dependent PDT cytotoxicity. The presence of GJIC composed of Connexin 32 increased the PDT phototoxicity in transfected HeLa cells and in the xenograft tumors, and the enhanced phototoxicity of Photofrin-mediated PDT by GJIC was related with ROS and calcium pathways. Our study indicates the possibility that up-regulation or maintenance of gap junction functionality may be used to increase the efficacy of PDT. The phototoxicity effect of Photofrin was substantially greater in Dox-treated cells, which expressed the Cx32 and formed the GJ, than Dox-untreated.
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Affiliation(s)
- Dengpan Wu
- Department of Pharmacology, Pharmacy School of Xuzhou Medical College, 221004, Xuzhou, P.R. China
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Pharmacy School of Xuzhou Medical College, 221004, Xuzhou, P.R. China
| | - Lixia Fan
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, 74 Zhongshan 2nd Road, Guangzhou, 510080, P.R. China
| | - Chengfang Xu
- Department of Gynaecology and Obstetrics, the Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510080, P.R. China
| | - Zhen Liu
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, 74 Zhongshan 2nd Road, Guangzhou, 510080, P.R. China
| | - Yuan Zhang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, 74 Zhongshan 2nd Road, Guangzhou, 510080, P.R. China
| | - Lucy Liu
- Department of Cell & Systems Biology, University of Toronto, Ontario, M5S3G5, Canada
| | - Qin Wang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, 74 Zhongshan 2nd Road, Guangzhou, 510080, P.R. China.
| | - Liang Tao
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, 74 Zhongshan 2nd Road, Guangzhou, 510080, P.R. China
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Pelletier RM, Akpovi CD, Chen L, Kumar NM, Vitale ML. Complementary expression and phosphorylation of Cx46 and Cx50 during development and following gene deletion in mouse and in normal and orchitic mink testes. Am J Physiol Regul Integr Comp Physiol 2015; 309:R255-76. [PMID: 26017495 PMCID: PMC4525330 DOI: 10.1152/ajpregu.00152.2015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 05/23/2015] [Indexed: 01/11/2023]
Abstract
Gap junction-mediated communication helps synchronize interconnected Sertoli cell activities. Besides, coordination of germ cell and Sertoli cell activities depends on gap junction-mediated Sertoli cell-germ cell communication. This report assesses mechanisms underlying the regulation of connexin 46 (Cx46) and Cx50 in mouse testis and those accompanying a "natural" seasonal and a pathological arrest of spermatogenesis, resulting from autoimmune orchitis (AIO) in mink. Furthermore, the impact of deleting Cx46 or Cx50 on the expression, phosphorylation of junction proteins, and spermatogenesis is evaluated. Cx46 mRNA and protein expression increased, whereas Cx50 decreased with adulthood in normal mice and mink. Cx46 mRNA and protein expression increased, whereas Cx50 decreased with adulthood in normal mice and mink. During the mink active spermatogenic phase, Cx50 became phosphorylated and localized to the site of the blood-testis barrier. By contrast, Cx46 was dephosphorylated and associated with annular junctions, suggesting phosphorylation/dephosphorylation of Cx46 and Cx50 involvement in the barrier dynamics. Cx46-positive annular junctions in contact with lipid droplets were found. Cx46 and Cx50 expression and localization were altered in mink with AIO. The deletion of Cx46 or Cx50 impacted on other connexin expression and phosphorylation and differently affected tight and adhering junction protein expression. The level of apoptosis, determined by ELISA, and a number of Apostain-labeled spermatocytes and spermatids/tubules were higher in mice lacking Cx46 (Cx46-/-) than wild-type and Cx50-/- mice, arguing for life-sustaining Cx46 gap junction-mediated exchanges in late-stage germ cells secluded from the blood by the barrier. The data show that expression and phosphorylation of Cx46 and Cx50 are complementary in seminiferous tubules.
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Affiliation(s)
- R-Marc Pelletier
- Department of Pathology and Cell Biology, Université de Montréal, Québec, Canada; and
| | - Casimir D Akpovi
- Department of Pathology and Cell Biology, Université de Montréal, Québec, Canada; and
| | - Li Chen
- Department of Pathology and Cell Biology, Université de Montréal, Québec, Canada; and
| | - Nalin M Kumar
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois
| | - María L Vitale
- Department of Pathology and Cell Biology, Université de Montréal, Québec, Canada; and
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12
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Kibschull M, Gellhaus A, Carette D, Segretain D, Pointis G, Gilleron J. Physiological roles of connexins and pannexins in reproductive organs. Cell Mol Life Sci 2015; 72:2879-98. [PMID: 26100514 PMCID: PMC11114083 DOI: 10.1007/s00018-015-1965-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 06/11/2015] [Indexed: 12/15/2022]
Abstract
Reproductive organs are complex and well-structured tissues essential to perpetuate the species. In mammals, the male and female reproductive organs vary on their organization, morphology and function. Connectivity between cells in such tissues plays pivotal roles in organogenesis and tissue functions through the regulation of cellular proliferation, migration, differentiation and apoptosis. Connexins and pannexins can be seen as major regulators of these physiological processes. In the present review, we assembled several lines of evidence demonstrating that these two families of proteins are essential for male and female reproduction.
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Affiliation(s)
- Mark Kibschull
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 25 Orde Street, Toronto, M5T 3H7 Canada
| | - Alexandra Gellhaus
- Department of Gynecology and Obstetrics, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Diane Carette
- UMR S1147, University Paris Descartes, 45 rue des Saints-Pères, 75006 Paris, France
- University of Versailles, 78035 Saint Quentin, France
- INSERM U 1065, University of Nice Sophia-Antipolis, 151 Route Saint-Antoine de Ginestière, BP 2 3194, 06204 Nice Cedex 3, France
| | - Dominique Segretain
- UMR S1147, University Paris Descartes, 45 rue des Saints-Pères, 75006 Paris, France
- University of Versailles, 78035 Saint Quentin, France
| | - Georges Pointis
- INSERM U 1065, University of Nice Sophia-Antipolis, 151 Route Saint-Antoine de Ginestière, BP 2 3194, 06204 Nice Cedex 3, France
| | - Jerome Gilleron
- INSERM U 1065, University of Nice Sophia-Antipolis, 151 Route Saint-Antoine de Ginestière, BP 2 3194, 06204 Nice Cedex 3, France
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13
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Rode K, Sieme H, Richterich P, Brehm R. Characterization of the equine blood-testis barrier during tubular development in normal and cryptorchid stallions. Theriogenology 2015; 84:763-72. [PMID: 26074069 DOI: 10.1016/j.theriogenology.2015.05.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 05/04/2015] [Accepted: 05/09/2015] [Indexed: 11/29/2022]
Abstract
The formation of the blood-testis barrier (BTB) is defined as occurring with the first appearance of spermatocytes at around puberty and is vital for normal spermatogenesis. This barrier between two adjacent Sertoli cells (SCs) consists of a cell junctional protein complex, which includes tight junctions (TJs), adherens junctions, and gap junctions. In many mammalian species, BTB composition has already been investigated, whereas little is known about the equine BTB. In the present study, immunohistochemistry and qualitative Western Blot analysis were used to assess the expression and distribution patterns of the junctional proteins claudin-11 (TJ), zonula occludens-1 (TJ associated), N-cadherin (adherens junctions), and connexin 43 (gap junctions) in equine testes during tubular development and in testes of stallions exhibiting unilateral cryptorchidism. Therefore, testes of 21 warmblood stallions (aged 12 months-11 years) were obtained during routine surgical castration. In the normal adult equine testis, the junctional proteins are localized at the basolateral region of the seminiferous tubules forming a circumferential seal corresponding to the known BTB localization. N-cadherin is additionally expressed along the lateral SC surface. In immature seminiferous cords still lacking a lumen, a diffuse distribution pattern of the junctional proteins throughout the SC cytoplasm is visible. As lumen formation advances, the immunolocalization shifts progressively toward the basolateral SC membranes. Additionally, apoptotic germ cells were detected and quantified in prepubertal stallions using terminal deoxynucleotidyl transferase dUTP nick end labeling assay and correlated with junctional protein localization. In the retained testis of cryptorchid stallions, which exhibit an aberrant testicular morphology, a deviating expression of the junctional proteins is visible. The present data show for the first time that (1) the equine SC junctional complex contains claudin-11, zonula occludens-1, N-Cadherin, and connexin 43, as already described for men or mice, and that (2) different distribution patterns of these proteins exist during testicular development in the context of lumen formation (lumen scores: 1-7) and in retained testes of unilateral cryptorchid stallions.
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Affiliation(s)
- K Rode
- Department of Anatomy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - H Sieme
- Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
| | - P Richterich
- Tierärztliche Klinik für Pferde auf Boyenstein, Beckum, Germany
| | - R Brehm
- Department of Anatomy, University of Veterinary Medicine Hannover, Hannover, Germany.
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Tang N, Wang Q, Wu D, Zhang S, Zhang Y, Tao L. Differential effects of paclitaxel and docetaxel on gap junctions affects their cytotoxicities in transfected HeLa cells. Mol Med Rep 2013; 8:638-44. [PMID: 23799576 DOI: 10.3892/mmr.2013.1546] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 05/23/2013] [Indexed: 11/06/2022] Open
Abstract
Gap junctions (GJs) enhance the cytotoxicity of specific cancer chemotherapeutic drugs and therefore, the inhibition of functional GJs may represent a mechanism by which the toxicity of chemotherapeutics in cancer cells can be reduced. In the present study, the effects and mechanisms of paclitaxel and docetaxel on GJ intercellular communication (GJIC) and the modulation of drug cytotoxicity were investigated in HeLa cells that were stably transfected with the connexin (Cx) 32 expression plasmid. Paclitaxel, but not docetaxel, was observed to inhibit dye‑coupling through junctional channels. Gating closure rather than the alteration of Cx32 expression or its membrane localization was responsible for the inhibitory action of paclitaxel on GJ function following short‑term exposure. The results revealed that the cytotoxicity of paclitaxel or docetaxel increased in the presence of functional GJs compared with that observed when GJIC was suppressed. In addition, paclitaxel‑induced downregulation of GJIC decreased the cytotoxicity of paclitaxel in the presence of functional GJs compared with that of docetaxel, which did not affect Cx32 channels. These observations demonstrated that the differential effects of paclitaxel and docetaxel on GJIC may affect the cytotoxicity of chemotherapeutic drugs. The present study provides a promising new approach to select antineoplastics and improve drug efficacy in carcinoma cells that form GJs.
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Affiliation(s)
- Nan Tang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong 510080, P.R. China
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15
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Abstract
The elucidation of how individual components of the Sertoli cell junctional complexes form and are dismantled to allow not only individual cells but whole syncytia of germinal cells to migrate from the basal to the lumenal compartment of the seminiferous epithelium without causing a permeability leak in the blood-testis barrier is amongst the most enigmatic yet, challenging and timely questions in testicular physiology. The intriguing key event in this process is how the barrier modulates its permeability during the periods of formation and dismantling of individual Sertoli cell junctions. The purpose of this review is therefore to first provide a reliable account on the normal formation, maintenance and dismantling process of the Sertoli cells junctions, then to assess the influence of the expression of their individual proteins, of the cytoskeleton associated with the junctions, and of the lipid content in the seminiferous tubules on the regulation of the their permeability barrier function. To help focus on the formation and dismantling of the Sertoli cell junctions, several considerations are based on data gleaned not only from rodents but from seasonal breeders as well because these animal models are characterized by exhaustive periods of junction assembly during development and the onset of the seasonal re-initiation of spermatogenesis as well as by an extensive junction dismantling period at the beginning of testicular regression, something unavailable in normal physiological conditions in continual breeders. Thus, the modulation of the permeability barrier function of the Sertoli cell junctions is analyzed in the physiological context of the blood-epidydimis barrier and in particular of the blood-testis barrier rather than in the context of a detailed account of the molecular composition and signalisation pathways of cell junctions. Moreover, the considerations discussed in this review are based on measurements performed on seminiferous tubule-enriched fractions gleaned at regular time intervals during development and the annual reproductive cycle.
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Kopera I, Durlej M, Hejmej A, Knapczyk-Stwora K, Duda M, Slomczynska M, Bilinska B. Differential Expression of Connexin 43 in Adult Pig Testes During Normal Spermatogenic Cycle and After Flutamide Treatment. Reprod Domest Anim 2011; 46:1050-60. [DOI: 10.1111/j.1439-0531.2011.01783.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Connexin 43 gene expression in male and female gonads of porcine offspring following in utero exposure to an anti-androgen, flutamide. Acta Histochem 2011; 113:6-12. [PMID: 19853283 DOI: 10.1016/j.acthis.2009.07.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2009] [Revised: 07/05/2009] [Accepted: 07/06/2009] [Indexed: 11/20/2022]
Abstract
The aim of this study was to show the effect of maternal exposure to flutamide on connexin 43 (Cx43) gene expression in testes and ovaries of 2-day-old piglets. Additionally, anogenital distance (AGD) was measured both in male and female offspring. Immunohistochemistry, Western blotting, and RT-PCR were performed to assess the immunoreactivity and the presence of Cx43 protein and it's mRNA, respectively. Following flutamide exposure strong immunostaining for Cx43 was observed between testicular Leydig cells, between granulosa cells of primary follicles, and between interstitial cells surrounding clusters of oocyte nests in the ovarian cortex as in the respective controls. Differences between the flutamide-treated groups and the controls obtained by qualitative immunohistochemistry were confirmed by quantitative image analysis (*P<0.05; **P<0.01). In Western blotting, Cx43 appeared as a band of 43kDa, whereas electrophoresis revealed PCR products of the predicted sizes. Screening for Cx43 expression revealed the presence of a transcript, both in control and in flutamide-treated pigs. The AGD values differed significantly from the control (*P<0.05). Overall, since no obvious changes in gonad morphology were observed and the Cx43 signal was present in all the examined tissues, it seems likely that androgens acting through ARs are not involved in the control of Cx43 gene expression in neonatal pig gonads.
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Pelletier RM, Akpovi CD, Chen L, Day R, Vitale ML. CX43 expression, phosphorylation, and distribution in the normal and autoimmune orchitic testis with a look at gap junctions joining germ cell to germ cell. Am J Physiol Regul Integr Comp Physiol 2010; 300:R121-39. [PMID: 20962206 DOI: 10.1152/ajpregu.00500.2010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Spermatogenesis requires connexin 43 (Cx43).This study examines normal gene transcription, translation, and phosphorylation of Cx43 to define its role on germ cell growth and Sertoli cell's differentiation, and identifies abnormalities arising from spontaneous autoimmune orchitis (AIO) in mink, a seasonal breeder and a natural model for autoimmunity. Northern blot analysis detected 2.8- and a 3.7-kb Cx43 mRNA bands in seminiferous tubule-enriched fractions. Cx43 mRNA increased in seminiferous tubule-enriched fractions throughout development and then seasonally with the completion of spermatogenesis. Cx43 protein levels increased transiently during the colonization of the tubules by the early-stage spermatocytes. Cx43 phosphorylated (PCx43) and nonphosphorylated (NPCx43) in Ser368 decreased during the periods of completion of meiosis and Sertoli cell differentiation, while Cx43 mRNA remained elevated throughout. PCx43 labeled chiefly the plasma membrane except by stage VII when vesicles were also labeled in Sertoli cells. Vesicles and lysosomes in Sertoli cells and the Golgi apparatus in the round spermatids were NPCx43 positive. A decrease in Cx43 gene expression was matched by a Cx43 protein increase in the early, not the late, phase of AIO. Total Cx43 and PCx43 decreased with the advance of orchitis. The study makes a novel finding of gap junctions connecting germ cells. The data indicate that Cx43 protein expression and phosphorylation in Ser368 are stage-specific events that may locally influence the acquisition of meiotic competence and the Sertoli cell differentiation in normal testis. AIO modifies Cx43 levels, suggesting changes in Cx43-mediated intercommunication and spermatogenic activity in response to cytokines imbalances in Sertoli cells.
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Affiliation(s)
- R-Marc Pelletier
- Department of Pathology and Cell Biology, Université de Montréal, Canada.
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Pointis G, Gilleron J, Carette D, Segretain D. Physiological and physiopathological aspects of connexins and communicating gap junctions in spermatogenesis. Philos Trans R Soc Lond B Biol Sci 2010; 365:1607-20. [PMID: 20403873 DOI: 10.1098/rstb.2009.0114] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Spermatogenesis is a highly regulated process of germ cell proliferation and differentiation, starting from spermatogonia to spermatocytes and giving rise to spermatids, the future spermatozoa. In addition to endocrine regulation, testicular cell-cell interactions are essential for spermatogenesis. This precise control is mediated through paracrine/autocrine pathways, direct intercellular contacts and through intercellular communication channels, consisting of gap junctions and their constitutive proteins, the connexins. Gap junctions are localized between adjacent Leydig cells, between Sertoli cells and between Sertoli cells and specific germ cells. This review focuses on the distribution of connexins within the seminiferous epithelium, their participation in gap junction channel formation, the control of their expression and the physiological relevance of these junctions in both the Sertoli-Sertoli cell functional synchronization and the Sertoli-germ cell dialogue. In this review, we also discuss the potential implication of disrupted connexin in testis cancer, since impaired expression of connexin has been described as a typical feature of tumoral proliferation.
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Affiliation(s)
- Georges Pointis
- INSERM U 895, Team 5 Physiopathology of Germ Cell Control: Genomic and Non-genomic Mechanisms, Bâtiment Universitaire ARCHIMED, C3M, 151 route Saint-Antoine de Ginestière, BP 2 3194, 06204 Nice Cedex 3, France
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Wang Q, You T, Yuan D, Han X, Hong X, He B, Wang L, Tong X, Tao L, Harris AL. Cisplatin and oxaliplatin inhibit gap junctional communication by direct action and by reduction of connexin expression, thereby counteracting cytotoxic efficacy. J Pharmacol Exp Ther 2010; 333:903-11. [PMID: 20215407 DOI: 10.1124/jpet.109.165274] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Cisplatin [cis-diamminedichloroplatinum(II)]/oxaliplatin [1,2-diamminocyclohexane(trans-1)oxolatoplatinum(II)] toxicity is enhanced by functional gap junctions between treated cells, implying that inhibition of gap junctions may decrease cytotoxic activity of these platinum-based agents. This study investigates the effect of gap junction modulation by cisplatin/oxaliplatin on cytotoxicity in a transformed cell line. The effects were explored using junctional channels expressed in transfected HeLa cells and purified hemichannels. Junctional channels showed a rapid, dose-dependent decrease in dye coupling with exposure to cisplatin/oxaliplatin. With longer exposure, both compounds also decreased connexin expression. Both compounds inhibit the activity of purified connexin hemichannels, over the same concentration range that they inhibit junctional dye permeability, demonstrating that inhibition occurs by direct interaction of the drugs with connexin protein. Cisplatin/oxaliplatin reduced the clonogenic survival of HeLa cells at low density and high density in a dose-dependent manner, but to a greater degree at high density, consistent with a positive effect of gap junctional intercellular communication (GJIC) on cytotoxicity. Reduction of GJIC by genetic or pharmacological means decreased cisplatin/oxaliplatin toxicity. At low cisplatin/oxaliplatin concentrations, where effects on connexin channels are minimal, the toxicity increased with increased cell density. However, higher concentrations strongly inhibited GJIC, and this counteracted the enhancing effect of greater cell density on toxicity. The present results indicate that inhibition of GJIC by cisplatin/oxaliplatin decreases their cytotoxicity. Direct inhibition of GJIC and reduction of connexin expression by cisplatin/oxaliplatin may thereby compromise the effectiveness of these compounds and be a factor in the development of resistance to this class of chemotherapeutic agents.
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Affiliation(s)
- Qin Wang
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, People's Republic of China
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Extending the knowledge in histochemistry and cell biology. Histochem Cell Biol 2009; 133:1-40. [PMID: 19946696 DOI: 10.1007/s00418-009-0665-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/17/2009] [Indexed: 01/21/2023]
Abstract
Central to modern Histochemistry and Cell Biology stands the need for visualization of cellular and molecular processes. In the past several years, a variety of techniques has been achieved bridging traditional light microscopy, fluorescence microscopy and electron microscopy with powerful software-based post-processing and computer modeling. Researchers now have various tools available to investigate problems of interest from bird's- up to worm's-eye of view, focusing on tissues, cells, proteins or finally single molecules. Applications of new approaches in combination with well-established traditional techniques of mRNA, DNA or protein analysis have led to enlightening and prudent studies which have paved the way toward a better understanding of not only physiological but also pathological processes in the field of cell biology. This review is intended to summarize articles standing for the progress made in "histo-biochemical" techniques and their manifold applications.
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State-of-the-art technologies, current opinions and developments, and novel findings: news from the field of histochemistry and cell biology. Histochem Cell Biol 2008; 130:1205-51. [PMID: 18985372 DOI: 10.1007/s00418-008-0535-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2008] [Indexed: 10/25/2022]
Abstract
Investigations of cell and tissue structure and function using innovative methods and approaches have again yielded numerous exciting findings in recent months and have added important data to current knowledge, inspiring new ideas and hypotheses in various fields of modern life sciences. Topics and contents of comprehensive expert reviews covering different aspects in methodological advances, cell biology, tissue function and morphology, and novel findings reported in original papers are summarized in the present review.
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