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Wang G. Genome Editing for Cystic Fibrosis. Cells 2023; 12:1555. [PMID: 37371025 DOI: 10.3390/cells12121555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 05/06/2023] [Accepted: 06/01/2023] [Indexed: 06/29/2023] Open
Abstract
Cystic fibrosis (CF) is a monogenic recessive genetic disorder caused by mutations in the CF Transmembrane-conductance Regulator gene (CFTR). Remarkable progress in basic research has led to the discovery of highly effective CFTR modulators. Now ~90% of CF patients are treatable. However, these modulator therapies are not curative and do not cover the full spectrum of CFTR mutations. Thus, there is a continued need to develop a complete and durable therapy that can treat all CF patients once and for all. As CF is a genetic disease, the ultimate therapy would be in-situ repair of the genetic lesions in the genome. Within the past few years, new technologies, such as CRISPR/Cas gene editing, have emerged as an appealing platform to revise the genome, ushering in a new era of genetic therapy. This review provided an update on this rapidly evolving field and the status of adapting the technology for CF therapy.
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Affiliation(s)
- Guoshun Wang
- Department of Microbiology, Immunology and Parasitology, Louisiana State University Health Sciences Center, CSRB 607, 533 Bolivar Street, New Orleans, LA 70112, USA
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2
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Hadziselimovic F, Verkauskas G, Stadler M. A novel role for CFTR interaction with LH and FGF in azoospermia and epididymal maldevelopment caused by cryptorchidism. Basic Clin Androl 2022; 32:10. [PMID: 35725394 PMCID: PMC9210799 DOI: 10.1186/s12610-022-00160-0] [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: 03/08/2022] [Accepted: 05/16/2022] [Indexed: 11/21/2022] Open
Abstract
Cryptorchidism occurs frequently in children with cystic fibrosis. Among boys with cryptorchidism and abrogated mini-puberty, the development of the epididymis and the vas deferens is frequently impaired. This finding suggests that a common cause underlies the abnormal development of Ad spermatogonia and the epididymis. The cystic fibrosis transmembrane conductance regulator (CFTR) is an ATP-binding cassette transporter protein that acts as a chloride channel. The CFTR gene has been associated with spermatogenesis and male fertility. In boys with cryptorchidism, prepubertal hypogonadotropic hypogonadism induces suboptimal expression of the ankyrin-like protein gene, ASZ1, the P-element induced wimpy testis-like gene, PIWIL, and CFTR. The abrogated expression of these gene leads to transposon reactivation, and ultimately, infertility. Curative gonadotropin-releasing hormone agonist (GnRHa) treatment stimulates the expression of CFTR and PIWIL3, which play important roles in the development of Ad spermatogonia and fertility. Furthermore, GnRHa stimulates the expression of the epididymal androgen-sensitive genes, CRISP1, WFDC8, SPINK13, and PAX2, which thereby promotes epididymal development. This review focuses on molecular evidence that favors a role for CFTR in cryptorchidism-induced infertility. Based on information available in the literature, we interpreted our RNA-Seq expression data obtained from samples before and after randomized GnRHa treatment in boys with bilateral cryptorchidism. We propose that, in boys with cryptorchidism, CFTR expression is controlled by luteinizing hormone and testosterone. Moreover, CFTR regulates the activities of genes that are important for fertility and Wolffian duct differentiation.
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Affiliation(s)
- Faruk Hadziselimovic
- Cryptorchidism Research Institute, Children's Day Care Center Liestal, 4410, Liestal, Schweiz, Switzerland.
| | - Gilvydas Verkauskas
- Children's Surgery Centre, Faculty of Medicine, Vilnius University, 01513, Vilnius, Lithuania
| | - Michael Stadler
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,Swiss Institute of Bioinformatics, Basel, Switzerland.,Faculty of Science, University of Basel, Basel, Switzerland
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3
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Carrageta DF, Bernardino RL, Alves MG, Oliveira PF. CFTR regulation of aquaporin-mediated water transport. VITAMINS AND HORMONES 2020; 112:163-177. [PMID: 32061340 DOI: 10.1016/bs.vh.2019.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is an anion channel responsible for the direct transport of bicarbonate and chloride. CFTR-dependent ionic transport is crucial for pH regulation and fluid homeodynamics among epithelial surfaces. Particularly, CFTR performs an essential role in the male reproductive tract, which requires a tight regulation of water and electrolytes in order to produce healthy spermatozoa. The absence or malfunction of CFTR results in cystic fibrosis, the most common lethal disease among Caucasians, that is characterized by an impaired fluid and ionic homeostasis in the whole organism. Due to the wide expression and importance of CFTR, the male reproductive tract is highly affected by cystic fibrosis, resulting in male infertility. Although CFTR is not permeable to water, this protein acts as a regulator of other protein channels, such as aquaporins. In fact, CFTR acts as a molecular partner of aquaporins in epithelial cells, regulating fluid homeodynamics. Herein, up-to-date data concerning the regulation of aquaporin-mediated water transport by CFTR will be discussed, highlighting the role of both channels in the male reproductive tract.
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Affiliation(s)
- David F Carrageta
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Raquel L Bernardino
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Marco G Alves
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Pedro F Oliveira
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal; Department of Genetics, Faculty of Medicine, University of Porto, Porto, Portugal; i3S-Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal.
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4
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Ritagliati C, Baro Graf C, Stival C, Krapf D. Regulation mechanisms and implications of sperm membrane hyperpolarization. Mech Dev 2018; 154:33-43. [PMID: 29694849 DOI: 10.1016/j.mod.2018.04.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 04/16/2018] [Accepted: 04/18/2018] [Indexed: 12/21/2022]
Abstract
Mammalian sperm are unable to fertilize the egg immediately after ejaculation. In order to gain fertilization competence, they need to undergo a series of biochemical and physiological modifications inside the female reproductive tract, known as capacitation. Capacitation correlates with two essential events for fertilization: hyperactivation, an asymmetric and vigorous flagellar motility, and the ability to undergo the acrosome reaction. At a molecular level, capacitation is associated to: phosphorylation cascades, modification of membrane lipids, alkalinization of the intracellular pH, increase in the intracellular Ca2+ concentration and hyperpolarization of the sperm plasma membrane potential. Hyperpolarization is a crucial event in capacitation since it primes the sperm to undergo the exocytosis of the acrosome content, essential to achieve fertilization of the oocyte.
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Affiliation(s)
- Carla Ritagliati
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET-UNR), Rosario 2000, Argentina.
| | - Carolina Baro Graf
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET-UNR), Rosario 2000, Argentina
| | - Cintia Stival
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET-UNR), Rosario 2000, Argentina
| | - Dario Krapf
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET-UNR), Rosario 2000, Argentina; Laboratorio de Especialidades Reproductivas, Facultad de Ciencias Bioquimicas y Farmacéuticas, UNR, Rosario 2000, Argentina.
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5
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Heidari S, Hojati Z, Motovali-Bashi M. Screening of Two Neighboring CFTR Mutations in Iranian Infertile Men with Non-Obstructive Azoospermia. INTERNATIONAL JOURNAL OF FERTILITY & STERILITY 2016; 10:390-394. [PMID: 28042420 PMCID: PMC5134755 DOI: 10.22074/ijfs.2016.4593] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Accepted: 07/24/2016] [Indexed: 11/06/2022]
Abstract
The genetic association between cystic fibrosis transmembrane conductance regulator
(CFTR) gene mutations and male infertility due to congenital bilateral absence of vas
deferens (CBAVD) is well established. Mutant CFTR, however may also be involved in
the etiology of male infertility in non-CBAVD cases. The present study was conducted
to estimate the frequency of ∆I507 and ∆F508 CFTR gene mutations in Iranian infertile
males. We undertook the first study of association between these CFTR mutations and
non-obstructive azoospermia in Iran.
In this case-control study, 100 fertile healthy fathers and 100 non-obstructive azoospermia’s
men were recruited from Isfahan Infertility Center (IIC) and Sari Saint Mary’s Infertility Center,
between 2008 and 2009. Screening of F508del and I507del mutations was
carried out by the multiplex-ARMS-PCR. Significance of differences in mutation frequencies
between the patient and control groups was assessed by Fisher’s exact test. The
ΔF508 was detected in three patients. However there are no significant association was
found between the presence of this mutated allele and infertility [OR=9.2 (allele-based)
and 7.2 (individual-based), P=0.179]. None of the samples carried the ΔI507 mutation.
Altogether, we show that neither ΔI507 nor ΔF508 is involved in this population of Iranian infertile males with non-obstructive azoospermia.
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Affiliation(s)
- Somayeh Heidari
- Department of Biology, Faculty of Sciences, University of Isfahan, Isfahan, Iran
| | - Zohreh Hojati
- Department of Biology, Faculty of Sciences, University of Isfahan, Isfahan, Iran
| | - Majid Motovali-Bashi
- Department of Biology, Faculty of Sciences, University of Isfahan, Isfahan, Iran
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Jesus TT, Bernardino RL, Martins AD, Sá R, Sousa M, Alves MG, Oliveira PF. Aquaporin-9 is expressed in rat Sertoli cells and interacts with the cystic fibrosis transmembrane conductance regulator. IUBMB Life 2014; 66:639-44. [PMID: 25270793 DOI: 10.1002/iub.1312] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 09/05/2014] [Indexed: 01/22/2023]
Abstract
Men with mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene are usually subfertile/infertile. Besides playing a role in Cl(-)/HCO3(-) transport, it has been proposed that CFTR interacts with water membrane transport systems, particularly aquaporins, to control seminiferous tubular secretion, which is regulated by the somatic Sertoli cells (SCs). As aquaporin-9 (AQP9) is highly expressed throughout the male reproductive tract, we hypothesized that it is also present in rat SCs and that it physically interacts with CFTR. To test this hypothesis, primary cultures of rat SCs were established, and expression of CFTR and AQP9 was assessed by RT-polymerase chain reactions (mRNA) and Western blot analysis (protein). A coimmunoprecipitation assay was used to evaluate the physical interaction between CFTR and AQP9. Our results show that CFTR and AQP9 are expressed in rat SCs. We were also able to detect a molecular interaction between CFTR and AQP9 in rat SCs. This is the first report describing the presence of AQP9, and its interaction with CFTR, in rat SCs. Moreover, our results provide evidence that CFTR is involved in water homeostasis of the seminiferous tubular secretion. These mechanisms may open new insights on therapeutic targets to counteract subfertility/infertility in men with cystic fibrosis and mutations in the CFTR gene.
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Affiliation(s)
- Tito T Jesus
- CICS-UBI, Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal; Department of Microscopy, Laboratory of Cell Biology, Multidisciplinary Unit for Biomedical Research, UMIB-FCT, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Portugal
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Sharma H, Mavuduru RS, Singh SK, Prasad R. Increased frequency of CFTR gene mutations identified in Indian infertile men with non-CBAVD obstructive azoospermia and spermatogenic failure. Gene 2014; 548:43-7. [PMID: 25010724 DOI: 10.1016/j.gene.2014.07.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 06/18/2014] [Accepted: 07/05/2014] [Indexed: 11/16/2022]
Abstract
High incidence of mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene is associated with congenital bilateral absence of the vas deferens (CBAVD) and is considered as the genital form of cystic fibrosis (CF). The CFTR gene may also be involved in the etiology of male infertility in cases other than CBAVD. The present study was conducted to identify the spectrum and frequency of CFTR gene mutations in infertile Indian males with non-CBAVD obstructive azoospermia (n=60) and spermatogenic failure (n=150). Conspicuously higher frequency of heterozygote F508del mutation was detected in infertile males with non-CBAVD obstructive azoospermia (11.6%) and spermatogenic failure (7.3%). Homozygous IVS(8)-5T allele frequency was also significantly higher in both groups in comparison to those in normal healthy individuals. Two mutations in exon 25 viz., R1358I and K1351R were identified as novel mutations in patients with non-CBAVD obstructive azoospermia. Mutation R1358I was predicted as probably damaging CFTR mutation. This is the first report from the Indian population, emphasizing increased frequency of CFTR gene mutations in male infertility other than CBAVD. Thus, it is suggested that screening of CFTR gene mutations may be required in infertile Indian males with other forms of infertility apart from CBAVD and willing for assisted reproduction technology.
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Affiliation(s)
- Himanshu Sharma
- Department of Biochemistry, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India
| | - Ravimohan S Mavuduru
- Department of Urology, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India
| | - Shrawan Kumar Singh
- Department of Urology, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India
| | - Rajendra Prasad
- Department of Biochemistry, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India.
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8
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Jesus TT, Bernardino RL, Martins AD, Sá R, Sousa M, Alves MG, Oliveira PF. Aquaporin-4 as a molecular partner of cystic fibrosis transmembrane conductance regulator in rat Sertoli cells. Biochem Biophys Res Commun 2014; 446:1017-21. [DOI: 10.1016/j.bbrc.2014.03.046] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 03/12/2014] [Indexed: 12/19/2022]
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9
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Novel regulators of spermatogenesis. Semin Cell Dev Biol 2014; 29:31-42. [PMID: 24594193 DOI: 10.1016/j.semcdb.2014.02.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 02/14/2014] [Accepted: 02/17/2014] [Indexed: 02/07/2023]
Abstract
Spermatogenesis is a multistep process that supports the production of millions of sperm daily. Understanding of the molecular mechanisms that regulate spermatogenesis has been a major focus for decades. Yet, the regulators involved in different cellular processes of spermatogenesis remain largely unknown. Human diseases that result in defective spermatogenesis have provided hints on the molecular mechanisms regulating this process. In this review, we have summarized recent findings on the function and signaling mechanisms of several genes that are known to be associated with disease or pathological processes, including CFTR, CD147, YWK-II and CT genes, and discuss their potential roles in regulating different processes of spermatogenesis.
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10
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Jiang LY, Shan JJ, Tong XM, Zhu HY, Yang LY, Zheng Q, Luo Y, Shi QX, Zhang SY. Cystic fibrosis transmembrane conductance regulator is correlated closely with sperm progressive motility and normal morphology in healthy and fertile men with normal sperm parameters. Andrologia 2013; 46:824-30. [PMID: 23998339 DOI: 10.1111/and.12155] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2013] [Indexed: 12/22/2022] Open
Abstract
Cystic fibrosis transmembrane conductance regulator (CFTR) has been demonstrated to be expressed in mature spermatozoa and correlated with sperm quality. Sperm CFTR expression in fertile men is higher than that in infertile men suffering from teratospermia, asthenoteratospermia, asthenospermia and oligospermia, but it is unknown whether CFTR is correlated with sperm parameters when sperm parameters are normal. In this study, 282 healthy and fertile men with normal semen parameters were classified into three age groups, group (I): age group of 20-29 years (98 cases, 27.1 ± 6.2), group (II): age group of 30-39 years (142 cases, 33.7 ± 2.6) and group (III): age group of more than or equal to 40 years (42 cases, 44.1 ± 4.6). Sperm concentration, total count and progressive motility were analysed by computer-assisted sperm analysis. Sperm morphology was analysed by modified Papanicolaou staining. Sperm CFTR expression was conducted by indirect immunofluorescence staining. There was a significant positive correlation (P < 0.001) between CFTR expression and sperm progressive motility (r = 0.221) and normal morphology (r = 0.202), but there were no correlations between sperm CFTR expression and semen volume, sperm concentration, sperm total count as well as male age (P > 0.05). Our findings show that CFTR expression is associated with sperm progressive motility and normal morphology in healthy and fertile men with normal sperm parameters, but not associated with the number of spermatozoa and male age.
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Affiliation(s)
- L-Y Jiang
- Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Sir Run Run Shaw Institute of Clinical Medicine of Zhejiang University, Hangzhou, Zhejiang, China
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Figueiras-Fierro D, Acevedo JJ, Martínez-López P, Escoffier J, Sepúlveda FV, Balderas E, Orta G, Visconti PE, Darszon A. Electrophysiological evidence for the presence of cystic fibrosis transmembrane conductance regulator (CFTR) in mouse sperm. J Cell Physiol 2013; 228:590-601. [PMID: 22833409 DOI: 10.1002/jcp.24166] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Accepted: 07/17/2012] [Indexed: 01/25/2023]
Abstract
Mammalian sperm must undergo a maturational process, named capacitation, in the female reproductive tract to fertilize the egg. Sperm capacitation is regulated by a cAMP/protein kinase A (PKA) pathway and involves increases in intracellular Ca(2+), pH, Cl(-), protein tyrosine phosphorylation, and in mouse and some other mammals a membrane potential hyperpolarization. The cystic fibrosis transmembrane conductance regulator (CFTR), a Cl(-) channel modulated by cAMP/PKA and ATP, was detected in mammalian sperm and proposed to modulate capacitation. Our whole-cell patch-clamp recordings from testicular mouse sperm now reveal a Cl(-) selective component to membrane current that is ATP-dependent, stimulated by cAMP, cGMP, and genistein (a CFTR agonist, at low concentrations), and inhibited by DPC and CFTR(inh) -172, two well-known CFTR antagonists. Furthermore, the Cl(-) current component activated by cAMP and inhibited by CFTR(inh) -172 is absent in recordings on testicular sperm from mice possessing the CFTR ΔF508 loss-of-function mutation, indicating that CFTR is responsible for this component. A Cl(-) selective like current component displaying CFTR characteristics was also found in wild type epididymal sperm bearing the cytoplasmatic droplet. Capacitated sperm treated with CFTR(inh) -172 undergo a shape change, suggesting that CFTR is involved in cell volume regulation. These findings indicate that functional CFTR channels are present in mouse sperm and their biophysical properties are consistent with their proposed participation in capacitation.
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Affiliation(s)
- Dulce Figueiras-Fierro
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca Morelos, Mexico
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Teixeira S, Sá R, Grangeia A, Silva J, Oliveira C, Ferráz L, Alves Â, Paiva S, Barros A, Sousa M. Immunohystochemical analysis of CFTR in normal and disrupted spermatogenesis. Syst Biol Reprod Med 2012; 59:53-9. [DOI: 10.3109/19396368.2012.718851] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Chen H, Ruan YC, Xu WM, Chen J, Chan HC. Regulation of male fertility by CFTR and implications in male infertility. Hum Reprod Update 2012; 18:703-13. [PMID: 22709980 DOI: 10.1093/humupd/dms027] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-activated Cl(-) and HCO(3)(-) conducting channel, mutations of which are known to be associated with male infertility. However, the underlying mechanisms remain elusive. METHODS Literature databases were searched for papers on the topics related to CFTR and male fertility and infertility with relevant keywords. Unpublished data from authors' laboratory were also included for analysis. RESULTS Clinical evidence shows increased mutation frequency or reduced CFTR expression in men with congenital bilateral absence of vas deferens (CBAVD) or sperm abnormalities, such as azoospermia teratospermia and oligoasthenospermia. Studies on primary rodent Sertoli cells and germ cells, as well as testes from CFTR knockout mice or a cryptorchidism model, yield findings indicating the involvement of CFTR in spermatogensis through the HCO(3)(-)/sAC/cAMP/CREB(CREM) pathway and the NF-κB/COX-2/PGE(2) pathway. Evidence also reveals a critical role of CFTR in sperm capacitation by directly or indirectly mediating HCO(3)(-) entry that is essential for capacitation. CFTR is emerging as a versatile player with roles in mediating different signaling pathways pertinent to various reproductive processes, in addition to its long-recognized role in electrolyte and fluid transport that regulates the luminal microenvironment of the male reproductive tract. CONCLUSIONS CFTR is a key regulator of male fertility, a defect of which may result in different forms of male infertility other than CBAVD. It would be worthwhile to further investigate the potential of developing novel diagnostic and contraceptive methods targeting CFTR.
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Affiliation(s)
- Hui Chen
- Sichuan University - The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, Key Laboratory of Obstetric, Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, People's Republic of China
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CFTR mediates bicarbonate-dependent activation of miR-125b in preimplantation embryo development. Cell Res 2012; 22:1453-66. [PMID: 22664907 DOI: 10.1038/cr.2012.88] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Although HCO(3)(-) is known to be required for early embryo development, its exact role remains elusive. Here we report that HCO(3)(-) acts as an environmental cue in regulating miR-125b expression through CFTR-mediated influx during preimplantation embryo development. The results show that the effect of HCO(3)(-) on preimplantation embryo development can be suppressed by interfering the function of a HCO(3)(-)-conducting channel, CFTR, by a specific inhibitor or gene knockout. Removal of extracellular HCO(3)(-) or inhibition of CFTR reduces miR-125b expression in 2 cell-stage mouse embryos. Knockdown of miR-125b mimics the effect of HCO(3)(-) removal and CFTR inhibition, while injection of miR-125b precursor reverses it. Downregulation of miR-125b upregulates p53 cascade in both human and mouse embryos. The activation of miR-125b is shown to be mediated by sAC/PKA-dependent nuclear shuttling of NF-κB. These results have revealed a critical role of CFTR in signal transduction linking the environmental HCO(3)(-) to activation of miR-125b during preimplantation embryo development and indicated the importance of ion channels in regulation of miRNAs.
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Orta G, Ferreira G, José O, Treviño CL, Beltrán C, Darszon A. Human spermatozoa possess a calcium-dependent chloride channel that may participate in the acrosomal reaction. J Physiol 2012; 590:2659-75. [PMID: 22473777 DOI: 10.1113/jphysiol.2011.224485] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Motility, maturation and the acrosome reaction (AR) are fundamental functions of mammalian spermatozoa. While travelling through the female reproductive tract, spermatozoa must mature through a process named capacitation, so that they can reach the egg and undergo the AR, an exocytotic event necessary to fertilize the egg. Though Cl⁻ is important for sperm capacitation and for the AR, not much is known about the molecular identity of the Cl⁻ transporters involved in these processes.We implemented a modified perforated patch-clamp strategy to obtain whole cell recordings sealing on the head of mature human spermatozoa.Our whole cell recordings revealed the presence of a Ca²⁺-dependent Cl⁻ current. The biophysical characteristics of this current and its sensitivity to niflumic acid (NFA) and 4,4-diisothiocyano-2,2-stilbene disulphonic acid (DIDIS) are consistent with those displayed by the Ca²⁺-dependent Cl⁻ channel from the anoctamin family (TMEM16). Whole cell patch clamp recordings in the cytoplasmic droplet of human spermatozoa corroborated the presence of these currents, which were sensitive to NFA and to a small molecule TMEM16A inhibitor (TMEM16Ainh, an aminophenylthiazole). Importantly, the human sperm AR induced by a recombinant human glycoprotein from the zona pellucida, rhZP3, displayed a similar sensitivity to NFA, DIDS and TMEM16Ainh as the sperm Ca²⁺-dependent Cl⁻ currents. Our findings indicate the presence of Ca²⁺-dependent Cl⁻ currents in human spermatozoa, that TMEM16A may contribute to these currents and also that sperm Ca²⁺-dependent Cl⁻ currents may participate in the rhZP3-induced AR.
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Affiliation(s)
- Gerardo Orta
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, CP 62210, México
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Li HG, Xu CM, Chen WY, Shi QX, Ni Y. Cystic fibrosis transmembrane conductance regulator protein expression rate in healthy spermatozoa is not correlated with ovum fertilisation rate. Andrologia 2011; 44 Suppl 1:231-8. [DOI: 10.1111/j.1439-0272.2011.01169.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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17
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Xu WM, Chen J, Chen H, Diao RY, Fok KL, Dong JD, Sun TT, Chen WY, Yu MK, Zhang XH, Tsang LL, Lau A, Shi QX, Shi QH, Huang PB, Chan HC. Defective CFTR-dependent CREB activation results in impaired spermatogenesis and azoospermia. PLoS One 2011; 6:e19120. [PMID: 21625623 PMCID: PMC3090391 DOI: 10.1371/journal.pone.0019120] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Accepted: 03/27/2011] [Indexed: 11/18/2022] Open
Abstract
Cystic fibrosis (CF) is the most common life-limiting recessive genetic disease
among Caucasians caused by mutations of the cystic fibrosis transmembrane
conductance regulator (CFTR) with over 95% male patients infertile.
However, whether CFTR mutations could affect spermatogenesis and result in
azoospermia remains an open question. Here we report compromised
spermatogenesis, with significantly reduced testicular weight and sperm count,
and decreased cAMP-responsive element binding protein (CREB) expression in the
testes of CFTR knockout mice. The involvement of CFTR in
HCO3− transport and the expression of the
HCO3− sensor, soluble adenylyl cyclase (sAC),
are demonstrated for the first time in the primary culture of rat Sertoli cells.
Inhibition of CFTR or depletion of HCO3− could
reduce FSH-stimulated, sAC-dependent cAMP production and phosphorylation of
CREB, the key transcription factor in spermatogenesis. Decreased CFTR and CREB
expression are also observed in human testes with azoospermia. The present study
reveals a previously undefined role of CFTR and sAC in regulating the cAMP-CREB
signaling pathway in Sertoli cells, defect of which may result in impaired
spermatogenesis and azoospermia. Altered CFTR-sAC-cAMP-CREB functional loop may
also underline the pathogenesis of various CF-related diseases.
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Affiliation(s)
- Wen Ming Xu
- Sichuan University-The Chinese University of
Hong Kong Joint Laboratory for Reproductive Medicine, West China Institute of
Women and Children's Health, West China Second University Hospital, Sichuan
University, Chengdu, People's Republic of China
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
| | - Jing Chen
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
| | - Hui Chen
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
| | - Rui Ying Diao
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
- Shenzhen Key Lab of Male Reproduction and
Genetics, Peking University Shenzhen Hospital, Shenzhen, People's Republic
of China
| | - Kin Lam Fok
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
| | - Jian Da Dong
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
| | - Ting Ting Sun
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
| | - Wen Ying Chen
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
- Department of Reproductive Physiology,
Zhejiang Academy of Medical Sciences, Hangzhou, People's Republic of
China
| | - Mei Kuen Yu
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
| | - Xiao Hu Zhang
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
| | - Lai Ling Tsang
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
| | - Ann Lau
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
| | - Qi Xian Shi
- Department of Reproductive Physiology,
Zhejiang Academy of Medical Sciences, Hangzhou, People's Republic of
China
| | - Qing Hua Shi
- Laboratory of Molecular and Cell Genetics,
Hefei National Laboratory for Physical Sciences at Microscale, School of Life
Sciences, University of Science and Technology of China, Hefei, People's
Republic of China
| | - Ping Bo Huang
- Department of Biology, Hong Kong University of
Science and Technology, Hong Kong, People's Republic of China
| | - Hsiao Chang Chan
- Sichuan University-The Chinese University of
Hong Kong Joint Laboratory for Reproductive Medicine, West China Institute of
Women and Children's Health, West China Second University Hospital, Sichuan
University, Chengdu, People's Republic of China
- Faculty of Medicine, School of Biomedical
Sciences, Epithelial Cell Biology Research Center, The Chinese University of
Hong Kong, Hong Kong, People's Republic of China
- * E-mail:
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18
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Hermo L, Pelletier RM, Cyr DG, Smith CE. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 4: intercellular bridges, mitochondria, nuclear envelope, apoptosis, ubiquitination, membrane/voltage-gated channels, methylation/acetylation, and transcription factors. Microsc Res Tech 2010; 73:364-408. [PMID: 19941288 DOI: 10.1002/jemt.20785] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
As germ cells divide and differentiate from spermatogonia to spermatozoa, they share a number of structural and functional features that are common to all generations of germ cells and these features are discussed herein. Germ cells are linked to one another by large intercellular bridges which serve to move molecules and even large organelles from the cytoplasm of one cell to another. Mitochondria take on different shapes and features and topographical arrangements to accommodate their specific needs during spermatogenesis. The nuclear envelope and pore complex also undergo extensive modifications concomitant with the development of germ cell generations. Apoptosis is an event that is normally triggered by germ cells and involves many proteins. It occurs to limit the germ cell pool and acts as a quality control mechanism. The ubiquitin pathway comprises enzymes that ubiquitinate as well as deubiquitinate target proteins and this pathway is present and functional in germ cells. Germ cells express many proteins involved in water balance and pH control as well as voltage-gated ion channel movement. In the nucleus, proteins undergo epigenetic modifications which include methylation, acetylation, and phosphorylation, with each of these modifications signaling changes in chromatin structure. Germ cells contain specialized transcription complexes that coordinate the differentiation program of spermatogenesis, and there are many male germ cell-specific differences in the components of this machinery. All of the above features of germ cells will be discussed along with the specific proteins/genes and abnormalities to fertility related to each topic.
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Affiliation(s)
- Louis Hermo
- Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University, 3640 University Street, Montreal, QC Canada H3A 2B2.
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19
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Li CY, Jiang LY, Chen WY, Li K, Sheng HQ, Ni Y, Lu JX, Xu WX, Zhang SY, Shi QX. CFTR is essential for sperm fertilizing capacity and is correlated with sperm quality in humans. Hum Reprod 2009; 25:317-27. [PMID: 19923167 DOI: 10.1093/humrep/dep406] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Our previous studies have demonstrated the cystic fibrosis transmembrane conductance regulator (CFTR) is important for capacitation and male fertility in mouse and guinea pig spermatozoa. However, the exact function of CFTR on human sperm fertilizing capacity, and correlation with sperm quality has not been established. The present study may shed light on some unexplained male infertility, and on a possible new method for diagnosis of male infertility and strategy for male contraception. METHODS To assess the effect of CFTR on human sperm fertilizing capacity, we examined sperm capacitation and the acrosome reaction using chlortetracycline staining, analyzed sperm hyperactivation by computer-assisted semen analysis (CASA), measured intracellular cAMP levels using ElA and evaluated sperm penetration of zona-free hamster eggs assay in fertile men. The percentage of spermatozoa expressing CFTR from fertile, healthy and infertile men (mainly teratospermic, asthenoteratospermic, asthenospermic and oligospermic) was conducted by indirect immunofluorescence staining. RESULTS Progesterone significantly facilitated human sperm capacitation and ZP3 triggered the acrosome reaction, both were significantly inhibited by CFTR inhibitor-172 (CFTRinh-172; 10 nM-1 microM) in a dose-dependent manner. The presence of 100 nM CFTRinh-172 markedly depressed intracellular cAMP levels, sperm hyperactivation and sperm penetration of zona-free hamster eggs. In addition, the percentage of spermatozoa expressing CFTR in the fertile men was significantly higher than healthy and infertile men categories (P < 0.01). CONCLUSIONS CFTR is essential for human sperm fertilizing capacity and the impairment of CFTR expression in spermatozoa is correlated with a reduction of sperm quality. These results suggest that defective expression of CFTR in human sperm may lead to the reduction of sperm fertilizing capacity.
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Affiliation(s)
- Chu-Yan Li
- Unit of Reproductive Physiology, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang 310013, China
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20
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Wakayama T, Nakata H, Kurobo M, Sai Y, Iseki S. Expression, localization, and binding activity of the ezrin/radixin/moesin proteins in the mouse testis. J Histochem Cytochem 2008; 57:351-62. [PMID: 19064715 DOI: 10.1369/jhc.2008.952440] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The ezrin, radixin, and moesin (ERM) proteins represent a family of adaptor proteins linking transmembrane proteins to the cytoskeleton. The seminiferous epithelium undergoes extensive changes in cellular composition, location, and shape, implicating roles of the membrane-cytoskeleton interaction. It remains unknown, however, whether the ERM proteins are expressed and play significant roles in the testis. In the present study, we examined the spatiotemporal expression of ERM proteins in the mouse testis by Western blotting and immunohistochemistry. Ezrin immunoreactivity was demonstrated in the cytoplasm of steps 15 and 16 spermatids from 5 weeks postpartum through adulthood, whereas radixin immunoreactivity was in the apical cytoplasm of Sertoli cells from 1 week through 2 weeks postpartum. No immunoreactivity for moesin was detected at any age. Immunoprecipitation demonstrated that ezrin was bound to the cytoskeletal component actin, whereas radixin was bound to both actin and tubulin. Of the transmembrane proteins known to interact with ERM proteins, only cystic fibrosis transmembrane conductance regulator, a chloride transporter, was bound to ezrin in elongated spermatids. These results suggest that ezrin is involved in spermiogenesis whereas radixin is involved in the maturation of Sertoli cells, through interaction with different sets of membrane proteins and cytoskeletal components.
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Affiliation(s)
- Tomohiko Wakayama
- Department of Histology and Embryology, Graduate School of Medical Science, Kanazawa University, 13-1 Takara-machi, Kanazawa, Ishikawa, 920-8640, Japan.
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21
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Chan HC, Ruan YC, He Q, Chen MH, Chen H, Xu WM, Chen WY, Xie C, Zhang XH, Zhou Z. The cystic fibrosis transmembrane conductance regulator in reproductive health and disease. J Physiol 2008; 587:2187-95. [PMID: 19015188 DOI: 10.1113/jphysiol.2008.164970] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is an anion channel regulated by cAMP-dependent phosphorylation, which is expressed in epithelial cells of a wide variety of tissues including the reproductive tracts. Mutations in the gene encoding CFTR cause cystic fibrosis, a common genetic disease in Caucasian populations with a multitude of clinical manifestations including infertility/subfertility in both sexes. However, the physiological role of CFTR in reproduction and its involvement in the pathogenesis of reproductive diseases remain largely unknown. This review discusses the role of CFTR in regulating fluid volume and bicarbonate secretion in the reproductive tracts and their importance in various reproductive events. We also discuss the contribution of CFTR dysfunction to a number of pathological conditions. The evidence presented is consistent with an important role of CFTR in reproductive health and disease, suggesting that CFTR might be a potential target for the diagnosis and treatment of reproductive diseases including infertility.
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Affiliation(s)
- Hsiao Chang Chan
- Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong.
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22
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Xu WM, Shi QX, Chen WY, Zhou CX, Ni Y, Rowlands DK, Yi Liu G, Zhu H, Ma ZG, Wang XF, Chen ZH, Zhou SC, Dong HS, Zhang XH, Chung YW, Yuan YY, Yang WX, Chan HC. Cystic fibrosis transmembrane conductance regulator is vital to sperm fertilizing capacity and male fertility. Proc Natl Acad Sci U S A 2007; 104:9816-21. [PMID: 17519339 PMCID: PMC1887595 DOI: 10.1073/pnas.0609253104] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cystic fibrosis transmembrane conductance regulator (CFTR) is an anion channel, mutations of which cause cystic fibrosis, a disease characterized by defective Cl(-) and HCO(3)(-) transport. Although >95% of all CF male patients are infertile because of congenital bilateral absence of the vas deferens (CBAVD), the question whether CFTR mutations are involved in other forms of male infertility is under intense debates. Here we report that CFTR is detected in both human and mouse sperm. CFTR inhibitor or antibody significantly reduces the sperm capacitation, and the associated HCO(3)(-)-dependent events, including increases in intracellular pH, cAMP production and membrane hyperpolarization. The fertilizing capacity of the sperm obtained from heterozygous CFTR mutant mice is also significantly lower compared with that of the wild-type. These results suggest that CFTR in sperm may be involved in the transport of HCO(3)(-) important for sperm capacitation and that CFTR mutations with impaired CFTR function may lead to reduced sperm fertilizing capacity and male infertility other than CBAVD.
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Affiliation(s)
- Wen Ming Xu
- *Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Qi Xian Shi
- Zhejiang Academy of Medical Sciences, Hangzhou 310013, China
| | - Wen Ying Chen
- *Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
- Zhejiang Academy of Medical Sciences, Hangzhou 310013, China
| | - Chen Xi Zhou
- *Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Ya Ni
- Zhejiang Academy of Medical Sciences, Hangzhou 310013, China
| | - Dewi Kenneth Rowlands
- *Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Guo Yi Liu
- Department of Physiology, Harbin Medical University, Harbin 150086, China
| | - Hu Zhu
- *Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Ze Gang Ma
- *Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Xiao Fei Wang
- Zhejiang Academy of Medical Sciences, Hangzhou 310013, China
| | - Zhang Hui Chen
- Zhejiang Academy of Medical Sciences, Hangzhou 310013, China
| | - Si Chang Zhou
- Zhejiang Academy of Medical Sciences, Hangzhou 310013, China
| | - Hong Shan Dong
- *Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
- Zhejiang University School of Medicine, College of Life Sciences, Hangzhou 310058, China; and
| | - Xiao Hu Zhang
- *Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Yiu Wa Chung
- *Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Yu Ying Yuan
- Zhejiang Academy of Medical Sciences, Hangzhou 310013, China
| | - Wan Xi Yang
- Zhejiang University School of Medicine, College of Life Sciences, Hangzhou 310058, China; and
| | - Hsiao Chang Chan
- *Epithelial Cell Biology Research Center, Li Ka Shing Institute of Health Sciences, Department of Physiology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
- Zhejiang University School of Medicine, College of Life Sciences, Hangzhou 310058, China; and
- To whom correspondence should be addressed. E-mail:
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23
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Hihnala S, Kujala M, Toppari J, Kere J, Holmberg C, Höglund P. Expression of SLC26A3, CFTR and NHE3 in the human male reproductive tract: role in male subfertility caused by congenital chloride diarrhoea. ACTA ACUST UNITED AC 2006; 12:107-11. [PMID: 16421216 DOI: 10.1093/molehr/gal009] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Congenital chloride diarrhoea (CLD) is a rare inherited disease caused by mutations in the solute carrier family 26 member 3 (SLC26A3) gene. Disruption of intestinal Cl(-)/HCO(3)(-) exchange causes watery Cl(-) rich diarrhoea from birth, and recently male subfertility was observed as a novel manifestation. Expression of SLC26A3, together with interacting proteins cystic fibrosis transmembrane conductance regulator (CFTR) and Na(+)/H(+) exchanger 3 (NHE3), was studied using immunohistochemistry in the testis (n = 2) and efferent ducts (ED) (n = 1) of patients with CLD (V317del genotype) and in the testis and epididymis (n = 11), seminal vesicle (n = 9) and prostate (n = 4) of the controls. SLC26A3 was immunolocalized in the head of the elongating spermatids (stages III-VI) and CFTR in the elongating spermatids (stages III and IV) and pachytene (stages III-V) and diplotene spermatocytes. In the non-ciliated cells of the ED, apical expression of all three proteins was observed, but only SLC26A3 and CFTR were detected on the luminal border of the apical mitochondria-rich cells (AMRC) of the ductus epididymis and in the epithelium of the seminal vesicle. Only CFTR was present in the epithelium of the prostatic duct. In the patient with CLD, the expression of both SLC26A3 and CFTR was absent in the ED, but testicular expression was identical to that of the controls. These results suggest a primary role for SLC26A3 in male reproduction. Tissue-specific co-expression with CFTR and NHE3 supports diverse functions of SLC26A3 and may have an impact on pathophysiology of male subfertility both in CLD and in cystic fibrosis (CF), as well as spermatoceles.
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Affiliation(s)
- S Hihnala
- Hospital for Children and Adolescents, Department of Medical Genetics, University of Helsinki, Finland.
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24
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Hernández-González EO, Sosnik J, Edwards J, Acevedo JJ, Mendoza-Lujambio I, López-González I, Demarco I, Wertheimer E, Darszon A, Visconti PE. Sodium and epithelial sodium channels participate in the regulation of the capacitation-associated hyperpolarization in mouse sperm. J Biol Chem 2005; 281:5623-33. [PMID: 16407190 DOI: 10.1074/jbc.m508172200] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In a process called capacitation, mammalian sperm gain the ability to fertilize after residing in the female tract. During capacitation the mouse sperm plasma membrane potential (E(m)) hyperpolarizes. However, the mechanisms that regulate sperm E(m) are not well understood. Here we show that sperm hyperpolarize when external Na(+) is replaced by N-methyl-glucamine. Readdition of external Na(+) restores a more depolarized E(m) by a process that is inhibited by amiloride or by its more potent derivative 5-(N-ethyl-N-isopropyl)-amiloride hydrochloride. These findings indicate that under resting conditions an electrogenic Na(+) transporter, possibly involving an amiloride sensitive Na(+) channel, may contribute to the sperm resting E(m). Consistent with this proposal, patch clamp recordings from spermatogenic cells reveal an amiloride-sensitive inward Na(+) current whose characteristics match those of the epithelial Na(+) channel (ENaC) family of epithelial Na(+) channels. Indeed, ENaC-alpha and -delta mRNAs were detected by reverse transcription-PCR in extracts of isolated elongated spermatids, and ENaC-alpha and -delta proteins were found on immunoblots of sperm membrane preparations. Immunostaining indicated localization of ENaC-alpha to the flagellar midpiece and of ENaC-delta to the acrosome. Incubations known to produce capacitation in vitro or induction of capacitation by cell-permeant cAMP analogs decreased the depolarizing response to the addition of external Na(+). These results suggest that increases in cAMP content occurring during capacitation may inhibit ENaCs to produce a required hyperpolarization of the sperm membrane.
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Affiliation(s)
- Enrique O Hernández-González
- Department of Veterinary and Animal Science, Paige Laboratories, University of Massachusetts, Amherst, MA 01003, USA
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25
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Acevedo JJ, Mendoza-Lujambio I, de la Vega-Beltrán JL, Treviño CL, Felix R, Darszon A. KATP channels in mouse spermatogenic cells and sperm, and their role in capacitation. Dev Biol 2005; 289:395-405. [PMID: 16343479 DOI: 10.1016/j.ydbio.2005.11.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2005] [Revised: 11/01/2005] [Accepted: 11/04/2005] [Indexed: 11/21/2022]
Abstract
Mammalian sperm must undergo a series of physiological changes after leaving the testis to become competent for fertilization. These changes, collectively known as capacitation, occur in the female reproductive tract where the sperm plasma membrane is modified in terms of its components and ionic permeability. Among other events, mouse sperm capacitation leads to an increase in the intracellular Ca(2+) and pH as well as to a hyperpolarization of the membrane potential. It is well known that ion channels play a crucial role in these events, though the molecular identity of the particular channels involved in capacitation is poorly defined. In the present work, we report the identification and potential functional role of K(ATP) channels in mouse spermatogenic cells and sperm. By using whole-cell patch clamp recordings in mouse spermatogenic cells, we found K(+) inwardly rectifying (K(ir)) currents that are sensitive to Ba(2+), glucose and the sulfonylureas (tolbutamide and glibenclamide) that block K(ATP) channels. The presence of these channels was confirmed using inhibitors of the ATP synthesis and K(ATP) channel activators. Furthermore, RT-PCR assays allowed us to detect transcripts for the K(ATP) subunits SUR1, SUR2, K(ir)6.1 and K(ir)6.2 in total RNA from elongated spermatids. In addition, immunoconfocal microscopy revealed the presence of these K(ATP) subunits in mouse spermatogenic cells and sperm. Notably, incubation of sperm with tolbutamide during capacitation abolished hyperpolarization and significantly decreased the percentage of AR in a dose-dependent fashion. Together, our results provide evidence for the presence of K(ATP) channels in mouse spermatogenic cells and sperm and disclose the contribution of these channels to the capacitation-associated hyperpolarization.
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Affiliation(s)
- Juan José Acevedo
- Department of Developmental Genetics and Molecular Physiology, Institute of Biotechnology, UNAM, Cuernavaca, Mexico
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26
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Yeung CH, Barfield JP, Cooper TG. Chloride Channels in Physiological Volume Regulation of Human Spermatozoa1. Biol Reprod 2005; 73:1057-63. [PMID: 16033995 DOI: 10.1095/biolreprod.105.044123] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
As with other mammalian species, human spermatozoa experience a decrease in extracellular osmolarity in cervical mucus upon ejaculation, which requires the efflux of osmolytes and water to counteract swelling that hinders mucus penetration. Recent evidence for the operation of K+ channels in the process of volume regulation suggests parallel involvement of Cl-/anion channels for electro-neutrality as in somatic cells. This was studied using ejaculated spermatozoa washed at seminal osmolality and incubated for 30 min in a medium of mucus osmolality in the presence of Cl- channel blockers. Increases in cell size measured as laser forward-scatter by flow cytometry were detected in the presence of 100 microM 5-nitro-2(3-phenylpropylamino) benzoic acid, 400 microM diisothiocyanato-stilbene-2,2'-disulphonic acid, and 20 microM tamoxifen. No volume changes were found with 400 microM 4-acetamido-4'-isothiocyanato-stilbene-2,2'-disulphonic acid, 200 microM verapamil, or niflumic acid, whereas 1 mM niflumic acid induced shrinkage. Among the candidate channel proteins, Western blotting revealed the presence of ClC-3 (CLCN3) at 87 kDa, but the absence of ClC-2 (CLCN2) from sperm proteins in all samples tested. ICln (CLNS1A) was found in only one of eight samples. Immunocytochemistry localized CLCN3 to the sperm tail. To confirm molecular identities, sperm mRNA was extracted and checked for quality by the presence of protamine 2 transcripts and the absence of sperm DNA and leukocyte mRNA using reverse transcription-polymerase chain reaction. Transcripts of Clcn3 were found in all samples and that of Clns1a in some but not all samples. Clcn3 was therefore considered the most likely candidate of Cl- channel involved in volume regulation of human sperm.
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Affiliation(s)
- C H Yeung
- Institute of Reproductive Medicine of the University, D-48129 Münster, Germany.
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27
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Muanprasat C, Sonawane ND, Salinas D, Taddei A, Galietta LJV, Verkman AS. Discovery of glycine hydrazide pore-occluding CFTR inhibitors: mechanism, structure-activity analysis, and in vivo efficacy. ACTA ACUST UNITED AC 2005; 124:125-37. [PMID: 15277574 PMCID: PMC2229623 DOI: 10.1085/jgp.200409059] [Citation(s) in RCA: 220] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) protein is a cAMP-regulated epithelial Cl− channel that, when defective, causes cystic fibrosis. Screening of a collection of 100,000 diverse small molecules revealed four novel chemical classes of CFTR inhibitors with Ki < 10 μM, one of which (glycine hydrazides) had many active structural analogues. Analysis of a series of synthesized glycine hydrazide analogues revealed maximal inhibitory potency for N-(2-naphthalenyl) and 3,5-dibromo-2,4-dihydroxyphenyl substituents. The compound N-(2-naphthalenyl)-[(3,5-dibromo-2,4-dihydroxyphenyl)methylene]glycine hydrazide (GlyH-101) reversibly inhibited CFTR Cl− conductance in <1 min. Whole-cell current measurements revealed voltage-dependent CFTR block by GlyH-101 with strong inward rectification, producing an increase in apparent inhibitory constant Ki from 1.4 μM at +60 mV to 5.6 μM at −60 mV. Apparent potency was reduced by lowering extracellular Cl− concentration. Patch-clamp experiments indicated fast channel closures within bursts of channel openings, reducing mean channel open time from 264 to 13 ms (−60 mV holding potential, 5 μM GlyH-101). GlyH-101 inhibitory potency was independent of pH from 6.5–8.0, where it exists predominantly as a monovalent anion with solubility ∼1 mM in water. Topical GlyH-101 (10 μM) in mice rapidly and reversibly inhibited forskolin-induced hyperpolarization in nasal potential differences. In a closed-loop model of cholera, intraluminal GlyH-101 (2.5 μg) reduced by ∼80% cholera toxin–induced intestinal fluid secretion. Compared with the thiazolidinone CFTR inhibitor CFTRinh-172, GlyH-101 has substantially greater water solubility and rapidity of action, and a novel inhibition mechanism involving occlusion near the external pore entrance. Glycine hydrazides may be useful as probes of CFTR pore structure, in creating animal models of CF, and as antidiarrheals in enterotoxic-mediated secretory diarrheas.
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Affiliation(s)
- Chatchai Muanprasat
- Department of Medicine, Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143-0521, USA
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Abstract
Congenital bilateral absence of the vas deferens (CBAVD) is a form of infertility with an autosomal recessive genetic background in otherwise healthy males. CBAVD is caused by cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations on both alleles in approximately 80% of cases. Striking CFTR genotypic differences are observed in cystic fibrosis (CF) and in CBAVD. The 5T allele is a CBAVD mutation with incomplete penetrance. Recent evidence confirmed that a second polymorphic locus exists and is a major CFTR modifier. The development of minigene models have led to results suggesting that CFTR exon 9 is skipped in humans because of unusual suboptimal 5' splice sites. An extremely rare T3 allele has been reported and it has recently been confirmed that the T3 allele dramatically increases exon 9 skipping and should be considered as a 'CF' mutation. Routine testing for the most prevalent mutations in the CF Caucasian population will miss most CFTR gene alterations, which can be detected only through exhaustive scanning of CFTR sequences. Finally, a higher than expected frequency of CFTR mutations and/or polymorphisms is now found in a growing number of monosymptomatic disorders, which creates a dilemma for setting nosologic boundaries between CF and diseases related to CFTR.
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Affiliation(s)
- Mireille Claustres
- Laboratoire de Génétique Moléculaire et Chromosomique, CHU de Montpellier, Institut Universitaire de Recherche Clinique (IURC), 641 Avenue du Doyen Gaston Giraud, 34093, Montpellier Cedex 5, France.
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Brochiero E, Dagenais A, Privé A, Berthiaume Y, Grygorczyk R. Evidence of a functional CFTR Cl(-) channel in adult alveolar epithelial cells. Am J Physiol Lung Cell Mol Physiol 2004; 287:L382-92. [PMID: 15107294 DOI: 10.1152/ajplung.00320.2002] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is expressed in the fetal lung, but during lung development it gradually disappears in cells of future alveolar spaces. Recent studies have implicated the CFTR in fluid transport by the adult alveolar epithelium, but its presence has not been demonstrated directly. This study re-evaluated CFTR expression and activity in the adult pulmonary epithelium by using freshly isolated rat alveolar type II (ATII) cells. CFTR mRNA was detected by semiquantitative polymerase chain reaction on the day of cell isolation but was rapidly reduced by 60% after 24 h of cell culture. This was paralleled by a similar decrease of surfactant protein A expression and alkaline phosphatase staining, markers of the ATII cell phenotype. CFTR expression increased significantly on day 4 in cells grown on filters at the air-liquid interface compared with cells submerged or grown on plastic. Significantly higher CFTR expression was detected in distal lung tissue compared with the trachea. The CFTR was also found at the protein level in Western blot experiments employing lysates of freshly isolated alveolar cells. Whole cell patch-clamp experiments revealed cAMP-stimulated, 5-nitro-2-(3-phenylpropylamino)-benzoate-sensitive Cl(-) conductance with a linear current-voltage relationship. In cell-attached membrane patches with 100 microM amiloride in pipette solution, forskolin stimulated channels of approximately 4 pS conductance. Our results indicate that 50-250 of functional CFTR Cl(-) channels occur in adult alveolar cells and could contribute to alveolar liquid homeostasis.
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Affiliation(s)
- Emmanuelle Brochiero
- Départemente de Médecine, Université de Montréal, Montresl, Quebec, Canada H2W 1T7
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Kunzelmann K, Mall M. Pharmacotherapy of the ion transport defect in cystic fibrosis: role of purinergic receptor agonists and other potential therapeutics. ACTA ACUST UNITED AC 2004; 2:299-309. [PMID: 14719996 DOI: 10.1007/bf03256658] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Cystic fibrosis (CF), is an autosomal recessive disease frequently seen in the Caucasian population. It is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. CF is characterized by enhanced airway Na(+) absorption, mediated by epithelial Na(+) channels (ENaC), and deficient Cl(-) transport. In addition, other mechanisms may contribute to the pathophysiological changes in the CF lung, such as defective regulation of HCO(3)(-) secretion. In other epithelial tissues, epithelial Na(+) conductance is either increased (intestine) or decreased (sweat duct) in CF. CFTR is a cyclic AMP-regulated epithelial Cl(-) channel, and appears to control the activity of several other transport proteins. Accordingly, defective epithelial ion transport in CF is likely to be a combination of defective Cl(-) channel function and impaired regulator function of CFTR, which in turn is linked to impaired mucociliary clearance and development of chronic lung disease. As the clinical course of CF is determined primarily by progressive lung disease, novel pharmacological strategies for the treatment of CF focus on correction of the ion transport defect in the airways. In recent years, it has been demonstrated that activation of purinergic receptors in airway epithelia by extracellular nucleotides (adenosine triphosphate/uridine triphosphate) has beneficial effects on mucus clearance in CF. Activation of the dominant class of metabotropic purinergic receptors, P2Y(2) receptors, appears to have a 2-fold benefit on ion transport in CF airways; excessive Na(+) absorption is attenuated, most likely by inhibition of the ENaC and, simultaneously, an alternative Ca(2+)-dependent Cl(-) channel is activated that may compensate for the CFTR Cl(-) channel defect. Thus activation of P2Y(2) receptors is expected to lead to improved hydration of the airway surface liquid in CF. Furthermore, purinergic activation has been shown to promote other components of mucociliary clearance such as ciliary beat frequency and mucus secretion. Clinical trials are under way to test the effect of synthetic purinergic compounds, such as the P2Y(2) receptor agonist INS37217, on the progression of lung disease in patients with CF. Administration of these compounds alone, or in combination with other drugs that inhibit accelerated Na(+) transport and help recover or increase residual activity of mutant CFTR, is most promising as successful therapy to counteract the ion transport defect in the airways of CF patients.
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Affiliation(s)
- Karl Kunzelmann
- Physiologisches Institut, Universitäts Regensburg, Regensburg, Germany.
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31
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Gong XD, Linsdell P, Cheung KH, Leung GPH, Wong PYD. Indazole inhibition of cystic fibrosis transmembrane conductance regulator Cl(-) channels in rat epididymal epithelial cells. Biol Reprod 2002; 67:1888-96. [PMID: 12444067 DOI: 10.1095/biolreprod.102.007450] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Previous studies have shown that two indazole compounds, lonidamine [1-(2,4-dichlorobenzyl)-indazole-3-carboxylic acid] and its analogue AF2785 [(1-(2,4-dichlorobenzyl)-indazol-3-acrylic acid], suppress fertility in male rats. We also found that these compounds inhibit the cystic fibrosis transmembrane conductance regulator chloride (CFTR-Cl(-)) current in epididymal epithelial cells. To further investigate how lonidamine and AF2785 inhibit the current, we used a spectral analysis protocol to study whole-cell CFTR current variance. Application of lonidamine or AF2785 to the extracellular membrane of rat epididymal epithelial cells introduced a new component to the whole-cell current variance. Spectral analysis of this variance suggested a block at a rate of 3.68 micro mol(-1)/sec(-1) and an off rate of 69.01 sec(-1) for lonidamine, and an on rate of 3.27 micro mol(-1)/sec(-1) and an off rate of 108 sec(-1) for AF2785. Single CFTR-Cl(-) channel activity using excised inside-out membrane patches from rat epididymal epithelial cells revealed that addition of lonidamine to the intracellular solution caused a flickery block (a reduction in channel-open time) at lower concentration (10 micro M) without any effect on open channel probability or single-channel current amplitude. At higher concentrations (50 and 100 micro M), lonidamine showed a flickery block and a decrease in open-channel probability. The flickery block by lonidamine was both voltage-dependent and concentration-dependent. These results suggest that lonidamine and AF2785, which are open-channel blockers of CFTR at low concentrations, also affect CFTR gating at high concentrations. We conclude that these indazole compounds provide new pharmacological tools for the investigation of CFTR. By virtue of their interference with reproductive processes, these drugs have the potential for being developed into novel male contraceptives.
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Affiliation(s)
- X D Gong
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova Scotia, Canada
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Gong XD, Li JCH, Leung GPH, Cheung KH, Wong PYD. A BK(Ca) to K(v) switch during spermatogenesis in the rat seminiferous tubules. Biol Reprod 2002; 67:46-54. [PMID: 12079998 DOI: 10.1095/biolreprod67.1.46] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Spermatogenesis is a complex cellular event during which the diploid germ cells differentiate and divide by mitosis and meiosis at specific time points along the spermatogenic cycle to generate the haploid spermatozoa. For this complex event to go in an orderly manner, cell differentiation and division must be precisely controlled by signals arising from within and outside the seminiferous tubules. Changes in the membrane potential of the germ cells are likely to be an important part of the signaling mechanism. We have applied the whole-cell patch clamp technique to identify and characterize ion channels in different spermatogenic cells from immature and mature rat testes fractionated by discontinuous Percoll gradient. A voltage- and Ca(2+)- dependent, outwardly rectifying current with gating and pharmacologic properties resembling the large conductance K(+) channels (BK(Ca)) was recorded from the spermatogonia and primary spermatocytes. Another voltage-dependent, outwardly rectifying current that was sensitive to 4-aminopyridine, a K(v) channel blocker, was detected in spermatocytes and early spermatids. This current is likely caused by the smaller conductance, voltage-sensitive K(+) channels (K(v)). In some spermatogonia, both the BK(Ca) channels and the K(v) channels could be simultaneously detected in the same cell. It appears that during the course of spermatogenesis, there is up-regulation of K(v) but down-regulation of BK(Ca). Reverse transcription-polymerase chain reaction, Western blot analysis, and immunohistochemistry further confirmed the differential expression of the ion channels in different spermatogenic cells. We conclude that these ion channels may play an important role in the control of spermatogenesis.
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Affiliation(s)
- X D Gong
- Department of Physiology, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong
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Calamita G, Mazzone A, Bizzoca A, Svelto M. Possible involvement of aquaporin-7 and -8 in rat testis development and spermatogenesis. Biochem Biophys Res Commun 2001; 288:619-25. [PMID: 11676488 DOI: 10.1006/bbrc.2001.5810] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fluid secretion and reabsorption are of central importance in male reproductive (MR) physiology. However, the related molecular mechanisms are poorly known. Here, potential roles for AQP7 and AQP8, two aquaporin water channels abundantly expressed in the MR tract, were investigated by studying their expression and distribution in the developing testis of the Wistar rat. By semiquantitative RT-PCR and immunoblotting, first expression of AQP7 was noted at postnatal day 45 (P45), with levels increasing substantially at P90 and remaining at high levels thereafter. AQP8 began to be expressed at P15, rapidly increased until P20, and remained fairly stable thereafter. Immunohistochemical analyses demonstrated AQP7 in elongated spermatids, testicular spermatozoa, and residual bodies at P45 with increased signal intensity thereafter. AQP8 was observed in primary spermatocytes from P20 to P30 and, in elongated spermatids, residual bodies and Sertoli cells at P30 and thereafter. The ontogeny and distribution of AQP7 and AQP8 in rat testis suggest involvement in major physiologic changes in testis development and spermatogenesis.
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Affiliation(s)
- G Calamita
- Department of General and Environmental Physiology, University of Bari, Bari, Italy.
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