1
|
Garoche C, Grimaldi M, Michelin E, Boulahtouf A, Marconi A, Brion F, Balaguer P, Aït-Aïssa S. Interlaboratory prevalidation of a new in vitro transcriptional activation assay for the screening of (anti-)androgenic activity of chemicals using the UALH-hAR cell line. Toxicol In Vitro 2023; 88:105554. [PMID: 36641061 DOI: 10.1016/j.tiv.2023.105554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 12/21/2022] [Accepted: 01/09/2023] [Indexed: 01/13/2023]
Abstract
We report an interlaboratory evaluation of a recently developed androgen receptor (AR) transactivation assay using the UALH-hAR reporter cell line that stably expresses the luciferase gene under the transcriptional control of androgen receptor elements (AREs) with no glucocorticoid receptor (GR) crosstalk. Herein, a two-step prevalidation study involving three laboratories was conducted to assess performance criteria of the method such as transferability as well as robustness, sensitivity, and specificity. The first step consisted in the validation of the transfer of the cell line to participant laboratories through the testing of three reference chemicals: the AR agonist dihydrotestosterone, the AR antagonist hydroxyflutamide and the glucocorticoid dexamethasone. Secondly, a blinded study was conducted by screening a selection of ten chemicals, including four AR agonists, five AR antagonists, and one non-active chemical. All test compounds yielded the same activity profiles in all laboratories. The logEC50 (agonist assay) or logIC50 (antagonist assay) were in the same range, with intra-laboratory coefficients of variation (CVs) of 0.1-3.4% and interlaboratory CVs of 1-4%, indicating very good within- and between-laboratory reproducibility. Our results were consistent with literature and regulatory data (OECD TG458). Overall, this interlaboratory study demonstrated that the UALH-hAR assay is transferable, produces reliable, accurate and specific (anti)androgenic activity of chemicals, and can be considered for further regulatory validation.
Collapse
Affiliation(s)
- Clémentine Garoche
- Institut National de l'Environnement Industriel et des Risques (INERIS), Unité Écotoxicologie des Substances et Milieux, UMR-I 02 SEBIO, 60550 Verneuil-en-Halatte, France.
| | - Marina Grimaldi
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université Montpellier 1, 34290 Montpellier, France
| | | | - Abdelhay Boulahtouf
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université Montpellier 1, 34290 Montpellier, France
| | | | - François Brion
- Institut National de l'Environnement Industriel et des Risques (INERIS), Unité Écotoxicologie des Substances et Milieux, UMR-I 02 SEBIO, 60550 Verneuil-en-Halatte, France
| | - Patrick Balaguer
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université Montpellier 1, 34290 Montpellier, France.
| | - Selim Aït-Aïssa
- Institut National de l'Environnement Industriel et des Risques (INERIS), Unité Écotoxicologie des Substances et Milieux, UMR-I 02 SEBIO, 60550 Verneuil-en-Halatte, France.
| |
Collapse
|
2
|
Timmermans S, Vandewalle J, Libert C. Dimerization of the Glucocorticoid Receptor and Its Importance in (Patho)physiology: A Primer. Cells 2022; 11:cells11040683. [PMID: 35203332 PMCID: PMC8870481 DOI: 10.3390/cells11040683] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/10/2022] [Accepted: 02/13/2022] [Indexed: 02/01/2023] Open
Abstract
The glucocorticoid receptor (GR) is a very versatile protein that comes in several forms, interacts with many proteins and has multiple functions. Numerous therapies are based on GRs’ actions but the occurrence of side effects and reduced responses to glucocorticoids have motivated scientists to study GRs in great detail. The notion that GRs can perform functions as a monomeric protein, but also as a homodimer has raised questions about the underlying mechanisms, structural aspects of dimerization, influencing factors and biological functions. In this review paper, we are providing an overview of the current knowledge and insights about this important aspect of GR biology.
Collapse
Affiliation(s)
- Steven Timmermans
- Center for Inflammation Research, VIB, 9052 Ghent, Belgium; (S.T.); (J.V.)
- Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium
| | - Jolien Vandewalle
- Center for Inflammation Research, VIB, 9052 Ghent, Belgium; (S.T.); (J.V.)
- Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium
| | - Claude Libert
- Center for Inflammation Research, VIB, 9052 Ghent, Belgium; (S.T.); (J.V.)
- Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium
- Correspondence:
| |
Collapse
|
3
|
Hornig NC, Holterhus PM. Molecular basis of androgen insensitivity syndromes. Mol Cell Endocrinol 2021; 523:111146. [PMID: 33385475 DOI: 10.1016/j.mce.2020.111146] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 12/17/2020] [Accepted: 12/21/2020] [Indexed: 02/07/2023]
Abstract
Individuals with complete androgen insensitivity syndrome show a female genital phenotype despite 46, XY gonosomes and the presence of androgen producing testes. This clinical observation indicates the resistance of the body and its cells to androgens like testosterone. At the molecular level, this hormone resistance is caused by hemizygous loss of function mutations in the X-chromosomal androgen receptor (AR) gene. Partial forms of androgen insensitivity syndrome (PAIS) show different degrees of virilisation largely depending on the remaining activity of the AR. Nevertheless, the phenotypic outcome can be variable even in presence of the same mutation and in the same kindred indicating the presence of further influencing factors. Importantly, the majority of clinically diagnosed PAIS individuals do not bear a mutation in their AR gene. A recent assay using the androgen regulated gene apolipoprotein D as biomarker is able to detect androgen insensitivity on the cellular level even in absence of an AR gene mutation. Using this assay a class of AIS without an AR-gene mutation was defined as AIS type II and suggests that unidentified cofactors of the AR are responsible for the PAIS phenotype. Here we outline the scientific progress made from the first clinical definition of AIS over biochemical and molecular characterizations to the concept of AIS type II. This review is based on publications in the PubMed database of the National Institutes of Health using the search terms androgen insensitivity syndrome and androgen receptor mutation.
Collapse
Affiliation(s)
- Nadine C Hornig
- Department of Pediatrics, Division of Pediatric Endocrinology and Diabetes, Christian-Albrechts-University Kiel & University Hospital Schleswig-Holstein, Kiel, Germany.
| | - Paul-Martin Holterhus
- Department of Pediatrics, Division of Pediatric Endocrinology and Diabetes, Christian-Albrechts-University Kiel & University Hospital Schleswig-Holstein, Kiel, Germany
| |
Collapse
|
4
|
De Bosscher K, Desmet SJ, Clarisse D, Estébanez-Perpiña E, Brunsveld L. Nuclear receptor crosstalk - defining the mechanisms for therapeutic innovation. Nat Rev Endocrinol 2020; 16:363-377. [PMID: 32303708 DOI: 10.1038/s41574-020-0349-5] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/12/2020] [Indexed: 02/06/2023]
Abstract
Nuclear receptor crosstalk can be defined as the interplay between different nuclear receptors or between their overlapping signalling pathways. A subset of nuclear receptors (such as PPARs and RARs) engage in the formation of well-characterized 'typical' heterodimers with RXR. 'Atypical' heterodimers (such as GR with PPARs, or PPAR with ERR) might form a novel class of physical complexes that might be more transient in nature. These heterodimers might harbour strong transcriptional flexibility, with no strict need for DNA binding of both partners. Direct crosstalk could stem from a pairwise physical association between atypical nuclear receptor heterodimers, either via pre-existing interaction pairs or via interactions that are newly induced with small molecules; such crosstalk might constitute an uncharted space to target nuclear receptor physiological and/or pathophysiological actions. In this Review, we discuss the emerging aspects of crosstalk in the nuclear receptor field and present various mechanistic crosstalk modes with examples that support applicability of the atypical heterodimer concept. Stabilization or disruption, in a context-dependent or cell type-dependent manner, of these more transient heterodimers is expected to fuel unprecedented translational approaches to yield novel therapeutic agents to treat major human diseases with higher precision.
Collapse
Affiliation(s)
- Karolien De Bosscher
- Translational Nuclear Receptor Research, VIB Center for Medical Biotechnology, UGent Department of Biomolecular Medicine, Gent, Belgium.
| | - Sofie J Desmet
- Translational Nuclear Receptor Research, VIB Center for Medical Biotechnology, UGent Department of Biomolecular Medicine, Gent, Belgium
| | - Dorien Clarisse
- Translational Nuclear Receptor Research, VIB Center for Medical Biotechnology, UGent Department of Biomolecular Medicine, Gent, Belgium
| | - Eva Estébanez-Perpiña
- Laboratory of Structural Biology, Department of Biochemistry and Molecular Biomedicine, Institute of Biomedicine (IBUB) of the University of Barcelona (UB), Barcelona, Spain
| | - Luc Brunsveld
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Technische Universiteit Eindhoven, Eindhoven, Netherlands
| |
Collapse
|
5
|
Bagherpoor Helabad M, Volkenandt S, Imhof P. Molecular Dynamics Simulations of a Chimeric Androgen Receptor Protein (SPARKI) Confirm the Importance of the Dimerization Domain on DNA Binding Specificity. Front Mol Biosci 2020; 7:4. [PMID: 32083093 PMCID: PMC7005049 DOI: 10.3389/fmolb.2020.00004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 01/10/2020] [Indexed: 11/21/2022] Open
Abstract
The DNA binding domains of Androgen/Glucocorticoid receptors (AR/GR), members of class I steroid receptors, bind as a homo-dimer to a cis-regulatory element. These response elements are arranged as inverted repeat (IR) of hexamer “AGAACA”, separated with a 3 base pairs spacer. DNA binding domains of the Androgen receptor, AR-DBDs, in addition, selectively recognize a direct-like repeat (DR) arrangement of this hexamer. A chimeric AR protein, termed SPARKI, in which the second zinc-binding motif of AR is swapped with that of GR, however, fails to recognize DR-like elements. By molecular dynamic simulations, we identify how the DNA binding domains of the wild type AR/GR, and also the chimeric SPARKI model, distinctly interact with both IR and DR response elements. AR binds more strongly to DR than GR binds to IR elements. A SPARKI model built from the structure of the AR (SPARKI-AR) shows significantly fewer hydrogen bond interactions in complex with a DR sequence than with an IR sequence. Moreover, a SPARKI model based on the structure of the GR (SPARKI-GR) shows a considerable distortion in its dimerization domain when complexed to a DR-DNA whereas it remains in a stable conformation in a complex with an IR-DNA. The diminished interaction of SPARKI-AR with and the instability of SPARKI-GR on DR response elements agree with SPARKI's lack of affinity for these sequences. The more GR-like binding specificity of the chimeric SPARKI protein is further emphasized by both SPARKI models binding even more strongly to IR elements than observed for the DNA binding domain of the GR.
Collapse
Affiliation(s)
| | - Senta Volkenandt
- Department of Physics, Freie Universität Berlin, Berlin, Germany
| | - Petra Imhof
- Department of Physics, Freie Universität Berlin, Berlin, Germany
| |
Collapse
|
6
|
Skowronska A, Tanski D, Jaskiewicz L, Skowronski MT. Modulation by steroid hormones and other factors on the expression of aquaporin-1 and aquaporin-5. VITAMINS AND HORMONES 2019; 112:209-242. [PMID: 32061342 DOI: 10.1016/bs.vh.2019.08.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- A Skowronska
- Department of Human Physiology, School of Medicine, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland.
| | - D Tanski
- Department of Anatomy and Animal Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland
| | - L Jaskiewicz
- Department of Human Physiology, School of Medicine, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland
| | - M T Skowronski
- Veterinary Center, University of Nicolaus Copernicus, Torun, Poland
| |
Collapse
|
7
|
Paris F, Boulahtouf A, Kalfa N, Guibal MP, Gaspari L, Servant N, Bourguet W, Sultan C, Balaguer P. Functional and Structural Study of the Amino Acid Substitution in a Novel Familial Androgen Receptor Mutation (W752G) Responsible for Complete Androgen Insensitivity Syndrome. Sex Dev 2018; 12:218-224. [PMID: 30064134 DOI: 10.1159/000491114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/05/2018] [Indexed: 11/19/2022] Open
Abstract
Mutations of the androgen receptor (AR) gene are the most frequent cause of 46,XY disorders of sex development. They are associated with a variety of phenotypes, ranging from phenotypic women (complete androgen insensitivity syndrome, CAIS) to milder degrees of undervirilization (partial forms) or men with only infertility (mild form). We identified a new W752G AR mutation responsible for a familial case of CAIS and performed an in vitro study and structural analysis of this mutation and the only other reported substitution affecting the same amino acid (W752R). Although sex assignment is not discussed in cases of CAIS, we show how the phenotype-genotype correlation can be refined by in vitro and structural studies according to the nature of the amino acid substitution, which in turn may have interesting impacts on the follow-up of these patients.
Collapse
|
8
|
Socha JK, Saito N, Wolak D, Sechman A, Hrabia A. Expression of aquaporin 4 in the chicken oviduct following tamoxifen treatment. Reprod Domest Anim 2018; 53:1339-1346. [PMID: 30028042 DOI: 10.1111/rda.13248] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 06/10/2018] [Indexed: 12/26/2022]
Abstract
This study was designed to examine whether aquaporin 4 (AQP4) is present in the chicken oviduct, and if so, whether its expression changes during pause in laying induced by tamoxifen (TMX; oestrogen receptor modulator) treatment. The control chickens were injected with a vehicle (ethanol) and the experimental ones with TMX at a dose of 6 mg/kg of body weight. Birds were treated daily until complete cessation of egg laying. The oviductal parts, that is the infundibulum, magnum, isthmus, shell gland and vagina were isolated from hens on day 8 of the experiment, and subsequently, the gene and protein expressions of AQP4 in tissues were examined by real-time PCR and Western blot, respectively. Immunohistochemical localization of AQP4 in the wall of the chicken oviduct was also investigated. Both mRNA and protein of AQP4 were found in all segments of the chicken oviduct. The relative expression [RQ] of AQP4 was the highest in the infundibulum and the vagina and the lowest, less detectable, in the magnum and isthmus. The pattern of AQP4 protein expression was similar to that of mRNA. Treatment of hens with TMX decreased the mRNA and protein levels of AQP4 in the oviduct. Immunohistochemistry demonstrated tissue and cell-dependent localization of AQP4 protein in the oviductal wall. The intensity of the immunopositive reaction was as follows: the infundibulum > vagina > shell gland ≥ isthmus >˃ magnum. In the control chickens, the immunoreactivity for AQP4 in all oviductal segments was stronger compared with the TMX-treated hens. The results obtained indicate that AQP4 takes part in the regulation of water transport required for the formation of egg in the chicken oviduct. Moreover, a relationship between oestrogen action and AQP4 gene and protein expression is suggested.
Collapse
Affiliation(s)
- Joanna K Socha
- Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Krakow, Poland
| | - Noboru Saito
- Laboratory of Animal Physiology, Graduate School of Environmental and Life Sciences, Okayama University, Okayama, Japan
| | - Dominika Wolak
- Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Krakow, Poland
| | - Andrzej Sechman
- Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Krakow, Poland
| | - Anna Hrabia
- Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Krakow, Poland
| |
Collapse
|
9
|
Lieberman HB, Rai AJ, Friedman RA, Hopkins KM, Broustas CG. Prostate cancer: unmet clinical needs and RAD9 as a candidate biomarker for patient management. Transl Cancer Res 2018; 7:S651-S661. [PMID: 30079300 PMCID: PMC6071673 DOI: 10.21037/tcr.2018.01.21] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Prostate cancer is a complex disease, with multiple subtypes and clinical presentations. Much progress has been made in recent years to understand the underlying genetic basis that drives prostate cancer. Such mechanistic information is useful for development of novel therapeutic targets, to identify biomarkers for early detection or to distinguish between aggressive and indolent disease, and to predict treatment outcome. Multiple tests have become available in recent years to address these clinical needs for prostate cancer. We describe several of these assays, summarizing test details, performance characteristics, and acknowledging their limitations. There is a pressing unmet need for novel biomarkers that can demonstrate improvement in these areas. We introduce one such candidate biomarker, RAD9, describe its functions in the DNA damage response, and detail why it can potentially fill this void. RAD9 has multiple roles in prostate carcinogenesis, making it potentially useful as a clinical tool for men with prostate cancer. RAD9 was originally identified as a radioresistance gene, and subsequent investigations revealed several key functions in the response of cells to DNA damage, including involvement in cell cycle checkpoint control, at least five DNA repair pathways, and apoptosis. Further studies indicated aberrant overexpression in approximately 45% of prostate tumors, with a strong correlation between RAD9 abundance and cancer stage. A causal relationship between RAD9 and prostate cancer was first demonstrated using a mouse model, where tumorigenicity of human prostate cancer cells after subcutaneous injection into nude mice was diminished when RNA interference was used to reduce the normally high levels of the protein. In addition to activity needed for the initial development of tumors, cell culture studies indicated roles for RAD9 in promoting prostate cancer progression by controlling cell migration and invasion through regulation of ITGB1 protein levels, and anoikis resistance by modulating AKT activation. Furthermore, RAD9 enhances the resistance of human prostate cancer cells to radiation in part by regulating ITGB1 protein abundance. RAD9 binds androgen receptor and inhibits androgen-induced androgen receptor's activity as a transcription factor. Moreover, RAD9 also acts as a gene-specific transcription factor, through binding p53 consensus sequences at target gene promoters, and this likely contributes to its oncogenic activity. Given these diverse and extensive activities, RAD9 plays important roles in the initiation and progression of prostate cancer and can potentially serve as a valuable biomarker useful in the management of patients with this disease.
Collapse
Affiliation(s)
- Howard B. Lieberman
- Center for Radiological Research, Columbia University College of Physicians and Surgeons, New York, NY, USA
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Alex J. Rai
- Department of Pathology and Cell Biology and Special Chemistry Laboratories, Columbia University Medical Center and New York Presbyterian Hospital, New York, NY, USA
| | - Richard A. Friedman
- Biomedical Informatics Shared Resource, Herbert Irving Comprehensive Cancer Center and Department of Biomedical Informatics, Columbia University, New York, NY, USA
| | - Kevin M. Hopkins
- Center for Radiological Research, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Constantinos G. Broustas
- Center for Radiological Research, Columbia University College of Physicians and Surgeons, New York, NY, USA
| |
Collapse
|
10
|
Abstract
The Androgen Receptor (AR), a member of the steroid hormone receptor family, plays important roles in the physiology and pathology of diverse tissues. AR ligands, which include circulating testosterone and locally synthesized dihydrotestosterone, bind to and activate the AR to elicit their effects. Ubiquitous expression of the AR, metabolism and cross reactivity with other receptors limit broad therapeutic utilization of steroidal androgens. However, the discovery of selective androgen receptor modulators (SARMs) and other tissue-selective nuclear hormone receptor modulators that activate their cognate receptors in a tissue-selective manner provides an opportunity to promote the beneficial effects of androgens and other hormones in target tissues with greatly reduced unwanted side-effects. In the last two decades, significant resources have been dedicated to the discovery and biological characterization of SARMs in an effort to harness the untapped potential of the AR. SARMs have been proposed as treatments of choice for various diseases, including muscle-wasting, breast cancer, and osteoporosis. This review provides insight into the evolution of SARMs from proof-of-concept agents to the cusp of therapeutic use in less than two decades, while covering contemporary views of their mechanisms of action and therapeutic benefits.
Collapse
Affiliation(s)
- Ramesh Narayanan
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN 38103, USA
| | | | - James T Dalton
- College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA.
| |
Collapse
|
11
|
Nowak M, Grzesiak M, Saito N, Kwaśniewska M, Sechman A, Hrabia A. Expression of aquaporin 4 in the chicken ovary in relation to follicle development. Reprod Domest Anim 2017; 52:857-864. [PMID: 28512792 DOI: 10.1111/rda.12990] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/01/2017] [Indexed: 12/14/2022]
Abstract
In the mammalian ovary, aquaporins (AQPs) are thought to be involved in the regulation of fluid transport within the follicular wall and antrum formation. Data concerning the AQPs in the avian ovary is very limited. Therefore, the present study was designed to examine whether the AQP4 is present in the chicken ovary, and if so, what is its distribution in the ovarian compartment of the laying hen. Localization of AQP4 in the ovarian follicles at different stage of development was also investigated. After decapitation of hens the stroma with primordial follicles and white (1-4 mm), yellowish (4-8 mm), small yellow and the three largest yellow pre-ovulatory follicles F3-F1 (F3 < F2 < F1; 20-36 mm) were isolated from the ovary. The granulosa and theca layers were separated from the pre-ovulatory follicles. The AQP4 mRNA and protein were detected in all examined ovarian compartments by the real-time PCR and Western blot analyses, respectively. The relative expression of AQP4 was depended on follicular size and the layer of follicular wall. It was the lowest in the granulosa layer of pre-ovulatory follicles and the highest in the ovarian stroma as well as white and yellowish follicles. Along with approaching of the largest follicle to ovulation the gradual decrease in AQP4 protein level in the granulosa layer was observed. Immunoreactivity for AQP4 was present in the granulosa and theca cells (theca interna ≥ theca externa > granulosa). The obtained results suggest that AQP4 may take part in the regulation of water transport required for follicle development in the chicken ovary.
Collapse
Affiliation(s)
- M Nowak
- Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Krakow, Poland
| | - M Grzesiak
- Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Krakow, Poland
| | - N Saito
- Laboratory of Animal Physiology, Graduate School of Environmental and Life Sciences, Okayama University, Okayama, Japan
| | - M Kwaśniewska
- Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Krakow, Poland
| | - A Sechman
- Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Krakow, Poland
| | - A Hrabia
- Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Krakow, Poland
| |
Collapse
|
12
|
Loh SY, Giribabu N, Gholami K, Salleh N. Effects of testosterone on mean arterial pressure and aquaporin (AQP)-1, 2, 3, 4, 6 and 7 expressions in the kidney of orchidectomized, adult male Sprague-Dawley rats. Arch Biochem Biophys 2016; 614:41-49. [PMID: 28024836 DOI: 10.1016/j.abb.2016.12.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 12/17/2016] [Accepted: 12/22/2016] [Indexed: 11/18/2022]
Abstract
We hypothesized that higher blood pressure in males than females could be due to testosterone effects on aquaporin (AQP) expression in kidneys. METHODS Orchidectomized adult male Sprague-Dawley (SD) rats received seven days subcutaneous testosterone treatment (125 μg/kg/day or 250 μg/kg/day), with or without flutamide or finasteride. Following completion of treatment, MAP was determined in rats under anaesthesia via carotid artery cannulation. In another cohort of rats, kidneys were removed following sacrifice and AQP-1, 2, 3, 4, 6 and 7 protein and mRNA levels were determined by Western blotting and Real-time PCR respectively. Distribution of AQP subunits' protein in the nephrons were visualized by immunofluorescence. RESULTS Testosterone caused MAP, AQP-1, 2, 4, 6 and 7 protein and mRNA levels in kidneys to increase while AQP-3 protein and mRNA levels in kidneys to decrease (p < 0.05). AQP-1 and 7 were found to be distributed in the proximal convoluted tubule (PCT) while AQP-2, 3, 4 and 6 were found to be distributed in the collecting ducts (CD). Effects of testosterone were antagonized by flutamide and finasteride. CONCLUSIONS Elevated expression of AQP-1, 2, 4, 6 and 7 under testosterone influence in kidneys could lead to increase H2O reabsorption which eventually lead to increase in blood pressure.
Collapse
Affiliation(s)
- Su Yi Loh
- Department of Physiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Nelli Giribabu
- Department of Physiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Khadijeh Gholami
- Department of Physiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Naguib Salleh
- Department of Physiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| |
Collapse
|
13
|
Pust A, Kylies D, Hube-Magg C, Kluth M, Minner S, Koop C, Grob T, Graefen M, Salomon G, Tsourlakis MC, Izbicki J, Wittmer C, Huland H, Simon R, Wilczak W, Sauter G, Steurer S, Krech T, Schlomm T, Melling N. Aquaporin 5 expression is frequent in prostate cancer and shows a dichotomous correlation with tumor phenotype and PSA recurrence. Hum Pathol 2016; 48:102-10. [DOI: 10.1016/j.humpath.2015.09.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 09/02/2015] [Accepted: 09/19/2015] [Indexed: 12/11/2022]
|
14
|
Grzesiak M, Knapczyk-Stwora K, Luck MR, Mobasheri A, Slomczynska M. Effect of Prenatal and Neonatal Anti-Androgen Flutamide Treatment on Aquaporin 5 Expression in the Adult Porcine Ovary. Reprod Domest Anim 2015; 51:105-13. [PMID: 26661749 DOI: 10.1111/rda.12652] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 11/12/2015] [Indexed: 02/06/2023]
Abstract
The growth of ovarian follicles is accompanied by fluid-filled antrum formation. Water movement within the follicular wall is predominantly transcellular via membranous water channels named aquaporins (AQPs). Androgens are important regulators of mammalian folliculogenesis, and their prenatal and/or neonatal deficiency affects female fertility in adulthood. Therefore, this study was performed to determine whether gestational or neonatal exposure to the anti-androgen flutamide influences androgen-dependent AQP5 expression in pre-antral and large antral follicles of adult pigs. Flutamide was injected into pregnant gilts between days 80 and 88 of gestation and into female piglets between days 2 and 10 post-natally. The ovaries were collected from flutamide-treated and non-treated (control) sexually mature pigs. In pre-antral follicles, AQP5 mRNA and protein levels were both downregulated following maternal (p < 0.01 and p < 0.01, respectively) and neonatal (p < 0.01 and p < 0.01, respectively) flutamide exposure. Likewise, the expression of mRNA (p < 0.01 and p < 0.001, respectively) and protein (p < 0.05 and p < 0.01, respectively) for AQP5 were diminished in large antral follicles in both groups. Immunohistochemistry showed decreased intensity of AQP5 immunoreaction in pre-antral (p < 0.01) and large antral (p < 0.001) follicles following flutamide treatment. Moreover, radioimmunological analysis revealed that changes observed in AQP5 expression corresponded with diminished follicular androgens production after both maternal (p < 0.05 and p < 0.05, respectively) and neonatal (p < 0.05 and p < 0.01, respectively) flutamide administration. Therefore, AQP5 appears to be a potential regulator of follicular fluid accumulation, under androgen control, and may be a key factor in antral follicle growth.
Collapse
Affiliation(s)
- M Grzesiak
- Department of Endocrinology, Institute of Zoology, Jagiellonian University in Krakow, Krakow, Poland.,Department of Animal Physiology and Endocrinology, University of Agriculture in Krakow, Krakow, Poland
| | - K Knapczyk-Stwora
- Department of Endocrinology, Institute of Zoology, Jagiellonian University in Krakow, Krakow, Poland
| | - M R Luck
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, UK
| | - A Mobasheri
- Department of Veterinary Preclinical Sciences, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Surrey, UK
| | - M Slomczynska
- Department of Endocrinology, Institute of Zoology, Jagiellonian University in Krakow, Krakow, Poland
| |
Collapse
|
15
|
Herak-Kramberger CM, Breljak D, Ljubojević M, Matokanović M, Lovrić M, Rogić D, Brzica H, Vrhovac I, Karaica D, Micek V, Dupor JI, Brown D, Sabolić I. Sex-dependent expression of water channel AQP1 along the rat nephron. Am J Physiol Renal Physiol 2015; 308:F809-21. [PMID: 25656365 DOI: 10.1152/ajprenal.00368.2014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 02/03/2015] [Indexed: 11/22/2022] Open
Abstract
In the mammalian kidney, nonglycosylated and glycosylated forms of aquaporin protein 1 (AQP1) coexist in the luminal and basolateral plasma membranes of proximal tubule and descending thin limb. Factors that influence AQP1 expression in (patho)physiological conditions are poorly known. Thus far, only angiotensin II and hypertonicity were found to upregulate AQP1 expression in rat proximal tubule in vivo and in vitro (Bouley R, Palomino Z, Tang SS, Nunes P, Kobori H, Lu HA, Shum WW, Sabolic I, Brown D, Ingelfinger JR, Jung FF. Am J Physiol Renal Physiol 297: F1575-F1586, 2009), a phenomenon that may be relevant for higher blood pressure observed in men and male experimental animals. Here we investigated the sex-dependent AQP1 protein and mRNA expression in the rat kidney by immunochemical methods and qRT-PCR in tissue samples from prepubertal and intact gonadectomized animals and sex hormone-treated gonadectomized adult male and female animals. In adult rats, the overall renal AQP1 protein and mRNA expression was ∼80% and ∼40% higher, respectively, in males than in females, downregulated by gonadectomy in both sexes and upregulated strongly by testosterone and moderately by progesterone treatment; estradiol treatment had no effect. In prepubertal rats, the AQP1 protein expression was low compared with adults and slightly higher in females, whereas the AQP1 mRNA expression was low and similar in both sexes. The observed differences in AQP1 protein expression in various experiments mainly reflect changes in the glycosylated form. The male-dominant expression of renal AQP1 in rats, which develops after puberty largely in the glycosylated form of the protein, may contribute to enhanced fluid reabsorption following the androgen- or progesterone-stimulated activities of sodium-reabsorptive mechanisms in proximal tubules.
Collapse
Affiliation(s)
| | - Davorka Breljak
- Molecular Toxicology, Institute for Medical Research and Occupational Health, Zagreb, Croatia
| | - Marija Ljubojević
- Molecular Toxicology, Institute for Medical Research and Occupational Health, Zagreb, Croatia
| | - Mirela Matokanović
- Molecular Toxicology, Institute for Medical Research and Occupational Health, Zagreb, Croatia
| | - Mila Lovrić
- Clinical Institute of Laboratory Diagnosis, University Hospital Center, Zagreb, Croatia
| | - Dunja Rogić
- Clinical Institute of Laboratory Diagnosis, University Hospital Center, Zagreb, Croatia
| | - Hrvoje Brzica
- Molecular Toxicology, Institute for Medical Research and Occupational Health, Zagreb, Croatia
| | - Ivana Vrhovac
- Molecular Toxicology, Institute for Medical Research and Occupational Health, Zagreb, Croatia
| | - Dean Karaica
- Molecular Toxicology, Institute for Medical Research and Occupational Health, Zagreb, Croatia
| | - Vedran Micek
- Molecular Toxicology, Institute for Medical Research and Occupational Health, Zagreb, Croatia
| | | | - Dennis Brown
- Program in Membrane Biology and Division of Nephrology, Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Ivan Sabolić
- Molecular Toxicology, Institute for Medical Research and Occupational Health, Zagreb, Croatia;
| |
Collapse
|
16
|
Starowicz A, Grzesiak M, Mobasheri A, Szoltys M. Immunolocalization of aquaporin 5 during rat ovarian follicle development and expansion of the preovulatory cumulus oophorus. Acta Histochem 2014; 116:457-65. [PMID: 24192214 DOI: 10.1016/j.acthis.2013.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 09/19/2013] [Accepted: 09/30/2013] [Indexed: 01/01/2023]
Abstract
Immunofluorescent localization of aquaporin 5 (AQP5) was investigated in rat ovarian follicles during development and preovulatory cumulus oophorus expansion. Ampullary cumuli oophori complexes (COCs) were examined. Analysis revealed that AQP5 immunostaining appeared in preantral follicles and formed a characteristic ring encircling and touching the oolemma. The staining represented most likely AQP5 functioning at the ends of corona radiata cell projections, anchoring on the oocyte surface. However, several hours after the presumptive preovulatory LH surge, when the process of expansion of COCs started, the AQP5 staining appeared also on the cumulus granulosa cells and in the extracellular matrix. In the postovulatory ampullary COCs the fluorescent ring was not observed, which may be the result of the well-established preovulatory withdrawal of projections from the zona pellucida. At that time-point immunofluorescent staining of AQP5 appeared in most oocytes and was also present in the apical membrane of epithelial cells of the oviduct ampulla. The latter observation suggests that after ovulation AQP5 is involved in the transcellular movement of water in the oviduct ampulla and oocytes in rats.
Collapse
|
17
|
Clinckemalie L, Spans L, Dubois V, Laurent M, Helsen C, Joniau S, Claessens F. Androgen regulation of the TMPRSS2 gene and the effect of a SNP in an androgen response element. Mol Endocrinol 2013; 27:2028-40. [PMID: 24109594 DOI: 10.1210/me.2013-1098] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
More than 50% of prostate cancers have undergone a genomic reorganization that juxtaposes the androgen-regulated promoter of TMPRSS2 and the protein coding parts of several ETS oncogenes. These gene fusions lead to prostate-specific and androgen-induced ETS expression and are associated with aggressive lesions, poor prognosis, and early-onset prostate cancer. In this study, we showed that an enhancer at 13 kb upstream of the TMPRSS2 transcription start site is crucial for the androgen regulation of the TMPRSS2 gene when tested in bacterial artificial chromosomal vectors. Within this enhancer, we identified the exact androgen receptor binding sequence. This newly identified androgen response element is situated next to two binding sites for the pioneer factor GATA2, which were identified by DNase I footprinting. Both the androgen response element and the GATA-2 binding sites are involved in the enhancer activity. Importantly, a single nucleotide polymorphism (rs8134378) within this androgen response element reduces binding and transactivation by the androgen receptor. The presence of this SNP might have implications on the expression and/or formation levels of TMPRSS2 fusions, because both have been shown to be influenced by androgens.
Collapse
Affiliation(s)
- Liesbeth Clinckemalie
- Molecular Endocrinology Laboratory, Department of Cellular and Molecular Medicine KU Leuven, Campus Gasthuisberg O&N1, PO Box 901, Herestraat 49, B-3000 Leuven, Belgium.
| | | | | | | | | | | | | |
Collapse
|
18
|
Grzesiak M, Williams L, Luck MR. Testosterone influences water transport in porcine granulosa cells. Reprod Domest Anim 2013; 48:e52-4. [PMID: 23506039 DOI: 10.1111/rda.12161] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 02/12/2013] [Indexed: 02/02/2023]
Abstract
The development of antral ovarian follicles entails fluid accumulation, but the mechanisms regulating water flux are unknown. Aquaporins are small, integral membrane proteins facilitating passive movement of water, some of which are known to be regulated by steroid hormones. The aim of this study was to determine whether testosterone (T) influences water transport in porcine granulosa cells. To assess water movement, the swelling of granulosa cells when moved from isotonic (319 mOsm) to hypotonic (95 mOsm) medium was measured after 12-hour pre-incubation in the presence of either testosterone (T), the antiandrogen 2-hydroxyflutamide (HF) or HF and T together. Pre-incubation with T increased the swelling of granulosa cells (p < 0.01) and this was abolished by HF (p < 0.001). Neither T nor HF affected cells in isotonic medium (319 mOsm). The results indicate that T acting via intracellular androgen receptors increases water permeability of porcine granulosa cells, probably through the regulation of aquaporin activity.
Collapse
Affiliation(s)
- M Grzesiak
- Department of Endocrinology, Institute of Zoology, Jagiellonian University, Krakow, Poland.
| | | | | |
Collapse
|
19
|
Clinckemalie L, Vanderschueren D, Boonen S, Claessens F. The hinge region in androgen receptor control. Mol Cell Endocrinol 2012; 358:1-8. [PMID: 22406839 DOI: 10.1016/j.mce.2012.02.019] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 02/21/2012] [Accepted: 02/22/2012] [Indexed: 01/19/2023]
Abstract
The region between the DNA-binding domain and the ligand-binding domain of nuclear receptors is termed the hinge region. Although this flexible linker is poorly conserved, diverse functions have been ascribed to it. For the androgen receptor (AR), the hinge region and in particular the (629)RKLKKL(634) motif, plays a central role in controlling AR activity, not only because it acts as the main part of the nuclear translocation signal, but also because it regulates the transactivation potential and intranuclear mobility of the receptor. It is also a target site for acetylation, ubiquitylation and methylation. The interplay between these different modifications as well as the phosphorylation at serine 650 will be discussed here. The hinge also has an important function in AR binding to classical versus selective androgen response elements. In addition, the number of coactivators/corepressors that might act via interaction with the hinge region is still growing. The importance of the hinge region is further illustrated by the different somatic mutations described in patients with androgen insensitivity syndrome and prostate cancer. In conclusion, the hinge region serves as an integrator for signals coming from different pathways that provide feedback to the control of AR activity.
Collapse
Affiliation(s)
- Liesbeth Clinckemalie
- Molecular Endocrinology Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg O&N1, Herestraat 49, 3000 Leuven, Belgium
| | | | | | | |
Collapse
|
20
|
De Benedetti A. The Tousled-Like Kinases as Guardians of Genome Integrity. ISRN MOLECULAR BIOLOGY 2012; 2012:627596. [PMID: 23869254 PMCID: PMC3712517 DOI: 10.5402/2012/627596] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The Tousled-like kinases (TLKs) function in processes of chromatin assembly, including replication, transcription, repair, and chromosome segregation. TLKs interact specifically (and phosphorylate) with the chromatin assembly factor Asf1, a histone H3-H4 chaperone, histone H3 itself at Ser10, and also Rad9, a key protein involved in DNA repair and cell cycle signaling following DNA damage. These interactions are believed to be responsible for the action of TLKs in double-stranded break repair and radioprotection and also in the propagation of the DNA damage response. Hence, I propose that TLKs play key roles in maintenance of genome integrity in many organisms of both kingdoms. In this paper, I highlight key issues of the known roles of these proteins, particularly in the context of DNA repair (IR and UV), their possible relevance to genome integrity and cancer development, and as possible targets for intervention in cancer management.
Collapse
Affiliation(s)
- Arrigo De Benedetti
- Department of Biochemistry and Molecular Biology and Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130, USA
| |
Collapse
|
21
|
Helsen C, Kerkhofs S, Clinckemalie L, Spans L, Laurent M, Boonen S, Vanderschueren D, Claessens F. Structural basis for nuclear hormone receptor DNA binding. Mol Cell Endocrinol 2012; 348:411-7. [PMID: 21801809 DOI: 10.1016/j.mce.2011.07.025] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 07/07/2011] [Accepted: 07/12/2011] [Indexed: 11/16/2022]
Abstract
The gene family of nuclear receptors is characterized by the presence of a typical, well conserved DNA-binding domain. In general, two zinc coordinating modules are folded such that an α-helix is inserted in the major groove of the DNA-helix displaying a sequence similar to one of two hexameric consensus motifs. Both zinc molecules coordinate four cysteines. Although the DNA-binding domains as well as the hormone response elements are very similar, each nuclear receptor will affect transcription of a specific set of target genes. This is in part due to some important receptor-specific variations on the general theme of DNA interaction. For most nuclear receptors, the DNA-binding domain dimerizes on DNA, which explains why most hormone response elements consist of a repeat of two hexamers. The hexamer dimers can be organized either as direct, inverted or everted repeats with spacers of varying lengths. The DNA can be bound by homodimers, heterodimers and for some orphan receptors, as monomer. Another key element for DNA binding by nuclear receptors is the carboxy-terminal extension of the DNA-binding domain extending into the hinge region. This part not only co-determines sequence specificity, but also affects other functions of the receptors like nuclear translocation, intranuclear mobility and transactivation potential. Moreover, allosteric signals passing through towards other receptor domains, explain why to some extent, the DNA elements can also be considered as controlling ligands.
Collapse
Affiliation(s)
- Christine Helsen
- Molecular Endocrinology Laboratory, Department Molecular Cell Biology, Campus GHB, ON1, Herestraat 49, 3000 Leuven, Belgium
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Ronald S, Sunavala-Dossabhoy G, Adams L, Williams B, De Benedetti A. The expression of Tousled kinases in CaP cell lines and its relation to radiation response and DSB repair. Prostate 2011; 71:1367-73. [PMID: 21647934 DOI: 10.1002/pros.21358] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 01/14/2011] [Indexed: 12/22/2022]
Abstract
BACKGROUND The Tousled-like kinases (TLKs) function in processes of chromatin assembly, including replication, transcription, repair, and chromosome segregation. TLK1/1B interacts specifically with the chromatin assembly factor Asf1, a histone H3-H4 chaperone, and with Rad9, a protein involved in DNA repair, and these interactions are believed to be responsible for the action of TLKs in double-strand break repair and radioprotection. METHODS Western blotting and RT-PCR were used to analyze the expression of TLK1, TLK1B, and TLK2 in a panel of prostate cancer (CaP) cell lines. The pattern of radiotolerance in the cell lines was analyzed in parallel. DU145 and PC-3 cells were also probed with assays utilizing transfected plasmids that could be cleaved in vivo with adeno-expressed HO nuclease to assess the potential contribution of TLK1/1B in DSB repair. RESULTS This is the first report of TLKs' expression in a panel of CaP cell lines and their relationship to radioresistance. Furthermore, expression of TLK1B in non-expressing PC-3 cells rendered them highly resistant to radiation, and conversely, knockdown to TLK1/1B in expressing DU145 reduced their radiotolerance. CONCLUSIONS TLKs appear to be intimately linked to the pattern of resistance to DNA damage, and specifically DSBs, a finding that was not reported before for any cell lines, and certainly not systematically for human prostate cell lines.
Collapse
Affiliation(s)
- Sharon Ronald
- Department of Biochemistry and Molecular Biology and the Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130-3932, USA
| | | | | | | | | |
Collapse
|
23
|
Foresta C, Strapazzon G, De Toni L, Gianesello L, Bruttocao A, Scarda A, Plebani M, Garolla A. Androgens modulate osteocalcin release by human visceral adipose tissue. Clin Endocrinol (Oxf) 2011; 75:64-9. [PMID: 21521268 DOI: 10.1111/j.1365-2265.2011.03997.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Androgens inhibit adipogenic differentiation through an androgen receptor (AR)-mediated pathway, increase lipolysis and reduce lipid accumulation in adipocytes. Undercarboxylated osteocalcin (ucOCN) regulates insulin and adiponectin secretion and is released by adipose tissue (AT). Our objective was to investigate, ex vivo and in vivo, the role of androgens on osteocalcin (OCN) modulation in human AT. DesiGN, PATIENTS, SETTING: Omental AT (OAT) for in vitro study and blood samples from 91 male patients of Padova University Hospital were used. MEASUREMENTS Omental AT was treated with dihydrotestosterone (DHT) in presence and in absence of flutamide. cOCN and ucOCN release by AT in a simple growth medium was evaluated by ELISA. OCN, both undercarboxylated (ucOCN) and carboxylated (cOCN) forms, was measured in serum by ELISA. RESULTS After 24-h DHT stimulation, the release of both cOCN and ucOCN by OAT was statistically increased (P < 0·05). Co-incubation with flutamide blunted OCN production. Overweight and obese patients had lower total and free testosterone (T), associated with lower ucOCN and ucOCN/OCN ratio. Free T was negatively correlated to BMI (ρ = -0·706, P < 0·05) and positively correlated to ucOCN/OCN ratio (ρ = 0·223, P < 0·05). CONCLUSIONS Our data suggest that androgens modulate OCN release by OAT in vitro. In addition to the anti-adipogenic role of androgens, they support a novel mechanism by which androgens could exert a protective effect in energy metabolism. This hypothesis appears even more significant considering that sexual hormones' levels are greatly altered in obesity and that AT is both highly involved in their clearance and able to produce OCN.
Collapse
Affiliation(s)
- Carlo Foresta
- Department of Histology, Microbiology and Medical Biotechnologies, Section of Clinical Pathology and Centre for Male Gamete CryopreservationEndocrine-Metabolic Laboratory (A.S.), Internal Medicine 3, University of PadovaEURAC Institute of Mountain Emergency Medicine (G.S.), Bozen/BolzanoDepartment of Oncological and Surgical Sciences, Clinical Surgery II (A.B), University Hospital of PadovaDepartment of Laboratory Medicine (M.P.), University Hospital of Padova, Padova, Italy
| | | | | | | | | | | | | | | |
Collapse
|
24
|
De Bruyn R, Bollen R, Claessens F. Identification and characterization of androgen response elements. Methods Mol Biol 2011; 776:81-93. [PMID: 21796522 DOI: 10.1007/978-1-61779-243-4_6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The androgen receptor (AR) has a DNA-binding domain that consists of two zinc coordinating modules. While residues of the first module make most of the sequence-specific contacts, the second module functions as a homodimerization interface (1). This explains why the androgen response elements (AREs) are organized as two 5'-AGAACA-3'-like motifs separated by three basepairs (2). AREs can be located near the promoters of androgen-responsive genes, but are also at considerable distances either upstream or downstream, so the initial steps in locating AREs can be challenging. Traditionally, AR-binding sites were identified by DNA cellulose competition assays (3) or by in vitro footprinting (4). However, the advent of the chromatin immunoprecipitation assays made it possible to identify genomic fragments to which the AR binds either directly or indirectly (5). To enable identification of AREs in such genomic fragments, we developed an in silico approach involving a weight matrix based on all known AREs (6). This will point out candidate AREs, which will still need experimental validation involving a direct interaction assay and a transactivation assay. We describe here the methods most fit to describe an ARE: the electrophoretic mobility shift and the transactivation assays.
Collapse
Affiliation(s)
- Reinhilde De Bruyn
- Department of Molecular Cell Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN, USA.
| | | | | |
Collapse
|
25
|
Lanzino M, Sisci D, Morelli C, Garofalo C, Catalano S, Casaburi I, Capparelli C, Giordano C, Giordano F, Maggiolini M, Andò S. Inhibition of cyclin D1 expression by androgen receptor in breast cancer cells--identification of a novel androgen response element. Nucleic Acids Res 2010; 38:5351-65. [PMID: 20421209 PMCID: PMC2938215 DOI: 10.1093/nar/gkq278] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Cyclin D1 gene (CCND1) is a critical mitogen-regulated cell-cycle control element whose transcriptional modulation plays a crucial role in breast cancer growth and progression. Here we demonstrate that the non-aromatizable androgen 5-α-dihydrotestosterone (DHT) inhibits endogenous cyclin D1 expression, as evidenced by reduction of cyclin D1 mRNA and protein levels, and decrease of CCND1-promoter activity, in MCF-7 cells. The DHT-dependent inhibition of CCND1 gene activity requires the involvement and the integrity of the androgen receptor (AR) DNA-binding domain. Site directed mutagenesis, DNA affinity precipitation assay, electrophoretic mobility shift assay and chromatin immunoprecipitation analyses indicate that this inhibitory effect is ligand dependent and it is mediated by direct binding of AR to an androgen response element (CCND1-ARE) located at −570 to −556-bp upstream of the transcription start site, in the cyclin D1 proximal promoter. Moreover, AR-mediated repression of the CCND1 involves the recruitment of the atypical orphan nuclear receptor DAX1 as a component of a multiprotein repressor complex also embracing the participation of Histone Deacetylase 1. In conclusion, identification of the CCND1-ARE allows defining cyclin D1 as a specific androgen target gene in breast and might contribute to explain the molecular basis of the inhibitory role of androgens on breast cancer cells proliferation.
Collapse
Affiliation(s)
- Marilena Lanzino
- Dipartimento Farmaco-Biologico, University of Calabria, Arcavacata di Rende (CS) 87036, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Denayer S, Helsen C, Thorrez L, Haelens A, Claessens F. The rules of DNA recognition by the androgen receptor. Mol Endocrinol 2010; 24:898-913. [PMID: 20304998 DOI: 10.1210/me.2009-0310] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The androgen receptor (AR) and glucocorticoid, progestagen, and mineralocorticoid receptors all recognize classical DNA response elements that are organized as inverted repeats of 5'-AGAACA-3'-like motifs with a three-nucleotide spacer. Next to such elements, the AR also recognizes a second type of androgen response element (ARE), the so-called selective AREs, which resemble more the direct repeats of the same hexamer. In this work, we show that not only the AR but also the progestagen receptor can recognize the selective AREs, whereas neither glucocorticoid nor mineralocorticoid receptor can. Recently, genomic AR-binding fragments have been postulated to contain AR-binding sites that diverge considerably from the classical ARE consensus. Extensive mutational analyses of these candidate motifs, however, reinstalls the values of the consensus sequence for the AREs as mentioned above, the importance of their dimeric nature and the presence of exactly three-nucleotide spacing. We developed a position-specific probability matrix that was used to predict with higher accuracy new AREs in different AR-binding regions. So far, all AR-binding genomic fragments that were analyzed contain AREs defined as receptor-dimer binding motifs with the ability to confer responsiveness to a reporter gene.
Collapse
Affiliation(s)
- Sarah Denayer
- Katholieke Universiteit Leuven, Campus Gasthuisberg, O/N1, Herestraat 49, 3000 Leuven, Belgium
| | | | | | | | | |
Collapse
|
27
|
Abstract
In spite of numerous advances in recent years, the complete list of direct target genes for nuclear receptors remains elusive. The integrated application of new computational and experimental methods reviewed in this chapter provides insight into the complex network of regulatory pathways mediated by nuclear receptors which is expected to improve the understanding of the physiology and the pathology of metabolism, development, homeostasis, and other fundamental processes.
Collapse
Affiliation(s)
- Gabor Varga
- Discovery Informatics, Lilly Research Labs, Eli Lilly and Company, Indianapolis, IN, USA.
| |
Collapse
|
28
|
Jazin E, Cahill L. Sex differences in molecular neuroscience: from fruit flies to humans. Nat Rev Neurosci 2010; 11:9-17. [DOI: 10.1038/nrn2754] [Citation(s) in RCA: 182] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
29
|
Current world literature. Curr Opin Endocrinol Diabetes Obes 2009; 16:260-77. [PMID: 19390324 DOI: 10.1097/med.0b013e32832c937e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
30
|
Claessens F, Denayer S, Van Tilborgh N, Kerkhofs S, Helsen C, Haelens A. Diverse roles of androgen receptor (AR) domains in AR-mediated signaling. NUCLEAR RECEPTOR SIGNALING 2008; 6:e008. [PMID: 18612376 PMCID: PMC2443950 DOI: 10.1621/nrs.06008] [Citation(s) in RCA: 167] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Accepted: 05/29/2008] [Indexed: 01/07/2023]
Abstract
Androgens control male sexual development and maintenance of the adult male phenotype. They have very divergent effects on their target organs like the reproductive organs, muscle, bone, brain and skin. This is explained in part by the fact that different cell types respond differently to androgen stimulus, even when all these responses are mediated by the same intracellular androgen receptor. To understand these tissue- and cell-specific readouts of androgens, we have to learn the many different steps in the transcription activation mechanisms of the androgen receptor (NR3C4). Like all nuclear receptors, the steroid receptors have a central DNA-binding domain connected to a ligand-binding domain by a hinge region. In addition, all steroid receptors have a relatively large amino-terminal domain. Despite the overall structural homology with other nuclear receptors, the androgen receptor has several specific characteristics which will be discussed here. This receptor can bind two types of androgen response elements (AREs): one type being similar to the classical GRE/PRE-type elements, the other type being the more divergent and more selective AREs. The hormone-binding domain has low intrinsic transactivation properties, a feature that correlates with the low affinity of this domain for the canonical LxxLL-bearing coactivators. For the androgen receptor, transcriptional activation involves the alternative recruitment of coactivators to different regions in the amino-terminal domain, as well as the hinge region. Finally, a very strong ligand-induced interaction between the amino-terminal domain and the ligand-binding domain of the androgen receptor seems to be involved in many aspects of its function as a transcription factor. This review describes the current knowledge on the structure-function relationships within the domains of the androgen receptor and tries to integrate the involvement of different domains, subdomains and motifs in the functioning of this receptor as a transcription factor with tissue- and cell-specific readouts.
Collapse
Affiliation(s)
- Frank Claessens
- Molecular Endocrinology Laboratory, Campus Gasthuisberg, University of Leuven, Leuven, Belgium.
| | | | | | | | | | | |
Collapse
|