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Khoshbakht S, Zomorodi Anbaji F, Darzi M, Esmaeili R. The endogenous association among MMP2/miR-1248/Circ_0087558/miR-643/ MAP2K6 axis can contribute to brain metastasis in basal-like subtype of breast cancer. Heliyon 2024; 10:e33195. [PMID: 39027611 PMCID: PMC11255566 DOI: 10.1016/j.heliyon.2024.e33195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 06/13/2024] [Accepted: 06/16/2024] [Indexed: 07/20/2024] Open
Abstract
Brain metastasis in basal-like breast cancer poses a significant challenge in cancer management due to its aggressive nature and limited treatment options. This study conducted a comprehensive analysis to explore the potential role of circular RNAs (circRNAs) as members of endogenous networks in developing breast cancer brain metastasis. Here, we utilized RNA sequencing data from primary breast cancer and brain metastasis tissue with basal-like subtype (n = 11). After quality controlling and preprocessing of fastq files, gene expression of mRNA and circRNAs were extracted from matched samples and normalized. Then, we employed the weighted gene co-expression network analysis approach to identify brain metastasis-associated circRNA modules ( S p e a r m a n Correlation > 0.5 , P - value < 0.05 ). Moreover, we found five protein-coding genes of PHLDA1, SLC12A2, MMP2, RGP1, and MAP2K6, significantly upregulated in brain metastatic tissues compared to primary breast cancer ( FDR < 0.05 ). These genes were enriched in the "GnRH signaling pathway" and "Fluid shear stress and atherosclerosis" pathways ( FDR < 0.05 ). Next, to explore the potential interactions between circRNAs and protein-coding genes, we reconstructed a competing endogenous RNA (ceRNA) network using mutual miRNAs between the circRNA module and upregulated mRNAs. Notably, we could detect two axes of circ_0087558/miR-604/MMP2 and MMP2/miR-1248/Circ_0087558/miR-643/MAP2K6 in ceRNA network. In conclusion, the identified circRNA-miRNA-mRNA axes might be therapeutic targets or diagnostic biomarkers for this challenging subtype of breast cancer. However, due to the small number of samples, further experimental validations are essential.
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Affiliation(s)
- Samane Khoshbakht
- Genetics Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
- Duke Molecular Physiology Institute, Duke University School of Medicine-Cardiology, Durham, NC, 27701, USA
| | - Fatemeh Zomorodi Anbaji
- Genetics Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
- Department of Cell &Molecular Biology, School of Biology, College of Science, University of Tehran, Tehran, Iran
| | - Mohammad Darzi
- Genetics Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Rezvan Esmaeili
- Genetics Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, 6565 MD Anderson Blvd., Houston, TX, 77030, USA
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Koklič T, Hrovat A, Guixà-González R, Rodríguez-Espigares I, Navio D, Frangež R, Uršič M, Kubale V, Plemenitaš A, Selent J, Šentjurc M, Vrecl M. Electron Paramagnetic Resonance Gives Evidence for the Presence of Type 1 Gonadotropin-Releasing Hormone Receptor (GnRH-R) in Subdomains of Lipid Rafts. Molecules 2021; 26:molecules26040973. [PMID: 33673080 PMCID: PMC7918721 DOI: 10.3390/molecules26040973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/02/2021] [Accepted: 02/08/2021] [Indexed: 11/16/2022] Open
Abstract
This study investigated the effect of type 1 gonadotropin releasing hormone receptor (GnRH-R) localization within lipid rafts on the properties of plasma membrane (PM) nanodomain structure. Confocal microscopy revealed colocalization of PM-localized GnRH-R with GM1-enriched raft-like PM subdomains. Electron paramagnetic resonance spectroscopy (EPR) of a membrane-partitioned spin probe was then used to study PM fluidity of immortalized pituitary gonadotrope cell line αT3-1 and HEK-293 cells stably expressing GnRH-R and compared it with their corresponding controls (αT4 and HEK-293 cells). Computer-assisted interpretation of EPR spectra revealed three modes of spin probe movement reflecting the properties of three types of PM nanodomains. Domains with an intermediate order parameter (domain 2) were the most affected by the presence of the GnRH-Rs, which increased PM ordering (order parameter (S)) and rotational mobility of PM lipids (decreased rotational correlation time (τc)). Depletion of cholesterol by methyl-β-cyclodextrin (methyl-β-CD) inhibited agonist-induced GnRH-R internalization and intracellular Ca2+ activity and resulted in an overall reduction in PM order; an observation further supported by molecular dynamics (MD) simulations of model membrane systems. This study provides evidence that GnRH-R PM localization may be related to a subdomain of lipid rafts that has lower PM ordering, suggesting lateral heterogeneity within lipid raft domains.
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Affiliation(s)
- Tilen Koklič
- Laboratory of Biophysics, Department of Condensed Matter Physics, Jožef Stefan Institute, 1000 Ljubljana, Slovenia; (T.K.); (M.Š.)
| | - Alenka Hrovat
- Veterinary Faculty, Institute of Preclinical Sciences, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia; (A.H.); (R.F.); (M.U.); (V.K.)
| | - Ramon Guixà-González
- Research Programme on Biomedical Informatics (GRIB), Department of Experimental and Health Sciences, Hospital del Mar Medical Research Institute (IMIM), Pompeu Fabra University (UPF), 08003 Barcelona, Spain; (R.G.-G.); (I.R.-E.); (D.N.); (J.S.)
- Laboratory of Biomolecular Research, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
- Condensed Matter Theory Group, PSI, 5232 Villigen, Switzerland
| | - Ismael Rodríguez-Espigares
- Research Programme on Biomedical Informatics (GRIB), Department of Experimental and Health Sciences, Hospital del Mar Medical Research Institute (IMIM), Pompeu Fabra University (UPF), 08003 Barcelona, Spain; (R.G.-G.); (I.R.-E.); (D.N.); (J.S.)
| | - Damaris Navio
- Research Programme on Biomedical Informatics (GRIB), Department of Experimental and Health Sciences, Hospital del Mar Medical Research Institute (IMIM), Pompeu Fabra University (UPF), 08003 Barcelona, Spain; (R.G.-G.); (I.R.-E.); (D.N.); (J.S.)
| | - Robert Frangež
- Veterinary Faculty, Institute of Preclinical Sciences, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia; (A.H.); (R.F.); (M.U.); (V.K.)
| | - Matjaž Uršič
- Veterinary Faculty, Institute of Preclinical Sciences, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia; (A.H.); (R.F.); (M.U.); (V.K.)
| | - Valentina Kubale
- Veterinary Faculty, Institute of Preclinical Sciences, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia; (A.H.); (R.F.); (M.U.); (V.K.)
| | - Ana Plemenitaš
- Faculty of Medicine, Institute of Biochemistry and Molecular Genetics, University of Ljubljana, 1000 Ljubljana, Slovenia;
| | - Jana Selent
- Research Programme on Biomedical Informatics (GRIB), Department of Experimental and Health Sciences, Hospital del Mar Medical Research Institute (IMIM), Pompeu Fabra University (UPF), 08003 Barcelona, Spain; (R.G.-G.); (I.R.-E.); (D.N.); (J.S.)
| | - Marjeta Šentjurc
- Laboratory of Biophysics, Department of Condensed Matter Physics, Jožef Stefan Institute, 1000 Ljubljana, Slovenia; (T.K.); (M.Š.)
| | - Milka Vrecl
- Veterinary Faculty, Institute of Preclinical Sciences, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, Slovenia; (A.H.); (R.F.); (M.U.); (V.K.)
- Correspondence: ; Tel.: +386-1-477-9118
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3
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Chang JP, Pemberton JG. Comparative aspects of GnRH-Stimulated signal transduction in the vertebrate pituitary - Contributions from teleost model systems. Mol Cell Endocrinol 2018; 463:142-167. [PMID: 28587765 DOI: 10.1016/j.mce.2017.06.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/31/2017] [Accepted: 06/01/2017] [Indexed: 02/07/2023]
Abstract
Gonadotropin-releasing hormone (GnRH) is a major regulator of reproduction through actions on pituitary gonadotropin release and synthesis. Although it is often thought that pituitary cells are exposed to only one GnRH, multiple GnRH forms are delivered to the pituitary of teleost fishes; interestingly this can include the cGnRH-II form usually thought to be non-hypophysiotropic. GnRHs can regulate other pituitary cell-types, both directly as well as indirectly, and multiple GnRH receptors (GnRHRs) may also be expressed in the pituitary, and even within a single pituitary cell-type. Literature on the differential actions of native GnRH isoforms in primary pituitary cells is largely derived from teleost fishes. This review will outline the diversity and complexity of GnRH-GnRHR signal transduction found within vertebrate gonadotropes as well as extra-gonadotropic sites with special emphasis on comparative studies from fish models. The implications that GnRHR transduction mechanisms are GnRH isoform-, function-, and cell-specific are also discussed.
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Affiliation(s)
- John P Chang
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
| | - Joshua G Pemberton
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
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Voliotis M, Garner KL, Alobaid H, Tsaneva-Atanasova K, McArdle CA. Gonadotropin-releasing hormone signaling: An information theoretic approach. Mol Cell Endocrinol 2018; 463:106-115. [PMID: 28760599 DOI: 10.1016/j.mce.2017.07.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 07/27/2017] [Accepted: 07/27/2017] [Indexed: 12/16/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) is a peptide hormone that mediates central control of reproduction, acting via G-protein coupled receptors that are primarily Gq coupled and mediate GnRH effects on the synthesis and secretion of luteinizing hormone and follicle-stimulating hormone. A great deal is known about the GnRH receptor signaling network but GnRH is secreted in short pulses and much less is known about how gonadotropes decode this pulsatile signal. Similarly, single cell measures reveal considerable cell-cell heterogeneity in responses to GnRH but the impact of this variability on signaling is largely unknown. Ordinary differential equation-based mathematical models have been used to explore the decoding of pulse dynamics and information theory-derived statistical measures are increasingly used to address the influence of cell-cell variability on the amount of information transferred by signaling pathways. Here, we describe both approaches for GnRH signaling, with emphasis on novel insights gained from the information theoretic approach and on the fundamental question of why GnRH is secreted in pulses.
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Affiliation(s)
- Margaritis Voliotis
- Department of Mathematics and Living Systems Institute, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, EX4 4QF, UK
| | - Kathryn L Garner
- Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, Whitson Street, Bristol, BS1 3NY, UK
| | - Hussah Alobaid
- Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, Whitson Street, Bristol, BS1 3NY, UK
| | - Krasimira Tsaneva-Atanasova
- Department of Mathematics and Living Systems Institute, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, EX4 4QF, UK; EPSRC Centre for Predictive Modeling in Healthcare, University of Exeter, Exeter, EX4 4QF, UK
| | - Craig A McArdle
- Laboratories for Integrative Neuroscience and Endocrinology, School of Clinical Sciences, University of Bristol, Whitson Street, Bristol, BS1 3NY, UK.
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5
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Edwards BS, Isom WJ, Navratil AM. Gonadotropin releasing hormone activation of the mTORC2/Rictor complex regulates actin remodeling and ERK activity in LβT2 cells. Mol Cell Endocrinol 2017; 439:346-353. [PMID: 27663077 PMCID: PMC5123956 DOI: 10.1016/j.mce.2016.09.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/26/2016] [Accepted: 09/19/2016] [Indexed: 12/16/2022]
Abstract
The mammalian target of rapamycin (mTOR) assembles into two different multi-protein complexes, mTORC1 and mTORC2. The mTORC2 complex is distinct due to the unique expression of the specific core regulatory protein Rictor (rapamycin-insensitive companion of mTOR). mTORC2 has been implicated in regulating actin cytoskeletal reorganization but its role in gonadotrope function is unknown. Using the gonadotrope-derived LβT2 cell line, we find that the GnRH agonist buserelin (GnRHa) phosphorylates both mTOR and Rictor. Interestingly, inhibition of mTORC2 blunts GnRHa-induced cyto-architectural rearrangements. Coincident with blunting of actin reorganization, inhibition of mTORC2 also attenuates GnRHa-mediated activation of both protein kinase C (PKC) and extracellular signal regulated kinase (ERK). Collectively, our data suggests that GnRHa-mediated mTORC2 activation is important in facilitating actin reorganization events critical for initiating PKC activity and subsequent ERK phosphorylation in the gonadotrope-derived LβT2 cell line.
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Affiliation(s)
- Brian S Edwards
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA.
| | - William J Isom
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA.
| | - Amy M Navratil
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA.
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6
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West C, Hanyaloglu AC. Minireview: Spatial Programming of G Protein-Coupled Receptor Activity: Decoding Signaling in Health and Disease. Mol Endocrinol 2015; 29:1095-106. [PMID: 26121235 DOI: 10.1210/me.2015-1065] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Probing the multiplicity of hormone signaling via G protein-coupled receptors (GPCRs) has demonstrated the complex signal pathways that underlie the multiple functions these receptors play in vivo. This is highly pertinent for the GPCRs key in reproduction and pregnancy that are exposed to cyclical and dynamic changes in their extracellular milieu. How such functional pleiotropy in GPCR signaling is translated to specific downstream cellular responses, however, is largely unknown. Emerging data strongly support mechanisms for a central role of receptor location in signal regulation via membrane trafficking. In this review, we discuss current progress in our understanding of the role membrane trafficking plays in location control of GPCR signaling, from organized plasma membrane signaling microdomains, potentially provided by both distinct endocytic and exocytic pathways, to more recent evidence for spatial control within the endomembrane system. Application of these emerging mechanisms in their relevance to GPCR activity in physiological and pathophysiological conditions will also be discussed, and in improving therapeutic strategies that exploits these mechanisms in order to program highly regulated and distinct signaling profiles.
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Affiliation(s)
- Camilla West
- Institute of Reproductive Biology and Development, Department of Surgery and Cancer, Imperial College London, London, W12 0NN, United Kingdom
| | - Aylin C Hanyaloglu
- Institute of Reproductive Biology and Development, Department of Surgery and Cancer, Imperial College London, London, W12 0NN, United Kingdom
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7
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Sezgin E, Levental I, Grzybek M, Schwarzmann G, Mueller V, Honigmann A, Belov VN, Eggeling C, Coskun U, Simons K, Schwille P. Partitioning, diffusion, and ligand binding of raft lipid analogs in model and cellular plasma membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1818:1777-84. [PMID: 22450237 DOI: 10.1016/j.bbamem.2012.03.007] [Citation(s) in RCA: 251] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Revised: 03/07/2012] [Accepted: 03/12/2012] [Indexed: 10/28/2022]
Abstract
Several simplified membrane models featuring coexisting liquid disordered (Ld) and ordered (Lo) lipid phases have been developed to mimic the heterogeneous organization of cellular membranes, and thus, aid our understanding of the nature and functional role of ordered lipid-protein nanodomains, termed "rafts". In spite of their greatly reduced complexity, quantitative characterization of local lipid environments using model membranes is not trivial, and the parallels that can be drawn to cellular membranes are not always evident. Similarly, various fluorescently labeled lipid analogs have been used to study membrane organization and function in vitro, although the biological activity of these probes in relation to their native counterparts often remains uncharacterized. This is particularly true for raft-preferring lipids ("raft lipids", e.g. sphingolipids and sterols), whose domain preference is a strict function of their molecular architecture, and is thus susceptible to disruption by fluorescence labeling. Here, we analyze the phase partitioning of a multitude of fluorescent raft lipid analogs in synthetic Giant Unilamellar Vesicles (GUVs) and cell-derived Giant Plasma Membrane Vesicles (GPMVs). We observe complex partitioning behavior dependent on label size, polarity, charge and position, lipid headgroup, and membrane composition. Several of the raft lipid analogs partitioned into the ordered phase in GPMVs, in contrast to fully synthetic GUVs, in which most raft lipid analogs mis-partitioned to the disordered phase. This behavior correlates with the greatly enhanced order difference between coexisting phases in the synthetic system. In addition, not only partitioning, but also ligand binding of the lipids is perturbed upon labeling: while cholera toxin B binds unlabeled GM1 in the Lo phase, it binds fluorescently labeled GMI exclusively in the Ld phase. Fluorescence correlation spectroscopy (FCS) by stimulated emission depletion (STED) nanoscopy on intact cellular plasma membranes consistently reveals a constant level of confined diffusion for raft lipid analogs that vary greatly in their partitioning behavior, suggesting different physicochemical bases for these phenomena.
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Affiliation(s)
- Erdinc Sezgin
- Biophysics/BIOTEC, TU Dresden. Tatzberg 47-51, 01307 Dresden, Germany
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Bliss SP, Navratil AM, Xie J, Miller A, Baccarini M, Roberson MS. ERK signaling, but not c-Raf, is required for gonadotropin-releasing hormone (GnRH)-induced regulation of Nur77 in pituitary gonadotropes. Endocrinology 2012; 153:700-11. [PMID: 22186412 PMCID: PMC3275385 DOI: 10.1210/en.2011-0247] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Stimulation of pituitary gonadotropes by hypothalamic GnRH leads to the rapid expression of several immediate early genes that play key roles in orchestrating the response of the gonadotrope to hypothalamic stimuli. Elucidation of the signaling mechanisms that couple the GnRH receptor to this immediate early gene repertoire is critical for understanding the molecular basis of GnRH action. Here we identify signaling mechanisms that underlie regulation of the orphan nuclear receptor Nur77 as a GnRH-responsive immediate early gene in αT3-1 cells and mouse gonadotropes in culture. Using a variety of approaches, we show that GnRH-induced transcriptional upregulation of Nur77 in αT3-1 cells is dependent on calcium, protein kinase C (PKC), and ERK signaling. Transcriptional activity of Nur77 within the gonadotrope is regulated posttranslationally by GnRH signaling via PKC but not ERK activity. Surprisingly, neither activation of the ERK pathway nor the transcriptional response of Nur77 to GnRH requires the activity of c-Raf kinase. In corroboration of these results, Nur77 responsiveness to GnRH was maintained in gonadotropes from mice with pituitary-targeted ablation of c-Raf kinase. In contrast, gonadotropes from mice with pituitary deficiency of ERK signaling failed to up-regulate Nur77 after GnRH stimulation. These results further clarify the role of ERK and PKC signaling in regulation of the GnRH-induced immediate early gene program as well as GnRH-induced transcription-stimulating activity of Nur77 in the gonadotrope and shed new light on the complex functional organization of this signaling pathway in the pituitary gonadotrope.
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Affiliation(s)
- Stuart P Bliss
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, USA
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9
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Kruit JK, Wijesekara N, Fox JEM, Dai XQ, Brunham LR, Searle GJ, Morgan GP, Costin AJ, Tang R, Bhattacharjee A, Johnson JD, Light PE, Marsh BJ, MacDonald PE, Verchere CB, Hayden MR. Islet cholesterol accumulation due to loss of ABCA1 leads to impaired exocytosis of insulin granules. Diabetes 2011; 60:3186-96. [PMID: 21998401 PMCID: PMC3219942 DOI: 10.2337/db11-0081] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
OBJECTIVE The ATP-binding cassette transporter A1 (ABCA1) is essential for normal insulin secretion from β-cells. The aim of this study was to elucidate the mechanisms underlying the impaired insulin secretion in islets lacking β-cell ABCA1. RESEARCH DESIGN AND METHODS Calcium imaging, patch clamp, and membrane capacitance were used to assess the effect of ABCA1 deficiency on calcium flux, ion channel function, and exocytosis in islet cells. Electron microscopy was used to analyze β-cell ultrastructure. The quantity and distribution of proteins involved in insulin-granule exocytosis were also investigated. RESULTS We show that a lack of β-cell ABCA1 results in impaired depolarization-induced exocytotic fusion of insulin granules. We observed disturbances in membrane microdomain organization and Golgi and insulin granule morphology in β-cells as well as elevated fasting plasma proinsulin levels in mice in the absence of β-cell ABCA1. Acute cholesterol depletion rescued the exocytotic defect in β-cells lacking ABCA1, indicating that elevated islet cholesterol accumulation directly impairs granule fusion and insulin secretion. CONCLUSIONS Our data highlight a crucial role of ABCA1 and cellular cholesterol in β-cells that is necessary for regulated insulin granule fusion events. These data suggest that abnormalities of cholesterol metabolism may contribute to the impaired β-cell function in diabetes.
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Affiliation(s)
- Janine K. Kruit
- Departments of Medical Genetics, Centre for Molecular Medicine, and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Nadeeja Wijesekara
- Departments of Medical Genetics, Centre for Molecular Medicine, and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jocelyn E. Manning Fox
- Department of Pharmacology, Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Xiao-Qing Dai
- Department of Pharmacology, Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Liam R. Brunham
- Departments of Medical Genetics, Centre for Molecular Medicine, and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Gavin J. Searle
- Department of Pharmacology, Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Garry P. Morgan
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Adam J. Costin
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Renmei Tang
- Departments of Medical Genetics, Centre for Molecular Medicine, and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alpana Bhattacharjee
- Departments of Medical Genetics, Centre for Molecular Medicine, and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - James D. Johnson
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Peter E. Light
- Department of Pharmacology, Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Brad J. Marsh
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Patrick E. MacDonald
- Department of Pharmacology, Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada
| | - C. Bruce Verchere
- Departments of Pathology & Laboratory Medicine and Surgery, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michael R. Hayden
- Departments of Medical Genetics, Centre for Molecular Medicine, and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
- Corresponding author: Michael R. Hayden,
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10
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Kim HJ, Gieske MC, Trudgen KL, Hudgins-Spivey S, Kim BG, Krust A, Chambon P, Jeong JW, Blalock E, Ko C. Identification of estradiol/ERα-regulated genes in the mouse pituitary. J Endocrinol 2011; 210:309-21. [PMID: 21700660 DOI: 10.1530/joe-11-0098] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Estrogen acts to prime the pituitary prior to the GnRH-induced LH surge by undiscovered mechanisms. This study aimed to identify the key components that mediate estrogen action in priming the pituitary. RNA extracted from the pituitaries of metestrous (low estrogen) and proestrus (high estrogen) stage mice, as well as from ovariectomized wild-type and estrogen receptor α (ERα) knockout mice treated with 17β-estradiol (E(2)) or vehicle, was used for gene expression microarray. Microarray data were then aggregated, built into a functional electronic database, and used for further characterization of E(2)/ERα-regulated genes. These data were used to compile a list of genes representing diverse biological pathways that are regulated by E(2) via an ERα-mediated pathway in the pituitary. This approach substantiates ERα regulation of membrane potential regulators and intracellular vesicle transporters, among others, but not the basic components of secretory machinery. Subsequent characterization of six selected genes (Cacna1a, Cacna1g, Cited1, Abep1, Opn3, and Kcne2) confirmed not only ERα dependency for their pituitary expression but also the significance of their expression in regulating GnRH-induced LH secretion. In conclusion, findings from this study suggest that estrogen primes the pituitary via ERα by equipping pituitary cells with critical cellular components that potentiate LH release on subsequent GnRH stimulations.
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Affiliation(s)
- Hyun Joon Kim
- Division of Reproductive Sciences, Department of Clinical Sciences, University of Kentucky, Lexington, KY 40536, USA
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