1
|
Brennan SC, Mun HC, Delbridge L, Kuchel PW, Conigrave AD. Temperature sensing by the calcium-sensing receptor. Front Physiol 2023; 14:1117352. [PMID: 36818436 PMCID: PMC9931745 DOI: 10.3389/fphys.2023.1117352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 01/16/2023] [Indexed: 02/05/2023] Open
Abstract
Whether GPCRs support the sensing of temperature as well as other chemical and physical modalities is not well understood. Introduction: Extracellular Ca2+ concentration (Ca2+ o) modulates core body temperature and the firing rates of temperature-sensitive CNS neurons, and hypocalcemia provokes childhood seizures. However, it is not known whether these phenomena are mediated by Ca2+ o-sensing GPCRs, including the calcium-sensing receptor (CaSR). In favor of the hypothesis, CaSRs are expressed in hypothalamic regions that support core temperature regulation, and autosomal dominant hypocalcemia, due to CaSR activating mutations, is associated with childhood seizures. Methods: Herein, we tested whether CaSR-dependent signaling is temperature sensitive using an established model system, CaSR-expressing HEK-293 cells. Results: We found that the frequency of Ca2+ o-induced Ca2+ i oscillations but not the integrated response was linearly dependent on temperature in a pathophysiologically relevant range. Chimeric receptor analysis showed that the receptor's C-terminus is required for temperature-dependent modulation and experiments with the PKC inhibitor GF109203X and CaSR mutants T888A and T888M, which eliminate a key phosphorylation site, demonstrated the importance of repetitive phosphorylation and dephosphorylation. Discussion and Conclusion: CaSRs mediate temperature-sensing and the mechanism, dependent upon repetitive phosphorylation and dephosphorylation, suggests that GPCRs more generally contribute to temperature-sensing.
Collapse
Affiliation(s)
- Sarah C. Brennan
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia,Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Hee-chang Mun
- Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Leigh Delbridge
- Department of Surgery, Mater Hospital, North Sydney, NSW, Australia
| | - Philip W. Kuchel
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | - Arthur D. Conigrave
- School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney, NSW, Australia,Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia,*Correspondence: Arthur D. Conigrave,
| |
Collapse
|
2
|
Jaggupilli A, Ly S, Nguyen K, Anand V, Yuan B, El-Dana F, Yan Y, Arvanitis Z, Piyarathna DWB, Putluri N, Piwnica-Worms H, Manning HC, Andreeff M, Battula VL. Metabolic stress induces GD2 + cancer stem cell-like phenotype in triple-negative breast cancer. Br J Cancer 2022; 126:615-627. [PMID: 34811508 PMCID: PMC8854435 DOI: 10.1038/s41416-021-01636-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 10/25/2021] [Accepted: 11/09/2021] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Metabolic stress resulting from nutrient deficiency is one of the hallmarks of a growing tumour. Here, we tested the hypothesis that metabolic stress induces breast cancer stem-like cell (BCSC) phenotype in triple-negative breast cancer (TNBC). METHODS Flow cytometry for GD2 expression, mass spectrometry and Ingenuity Pathway Analysis for metabolomics, bioinformatics, in vitro tumorigenesis and in vivo models were used. RESULTS Serum/glucose deprivation not only increased stress markers but also enhanced GD2+ BCSC phenotype and function in TNBC cells. Global metabolomics profiling identified upregulation of glutathione biosynthesis in GD2high cells, suggesting a role of glutamine in the BCSC phenotype. Cueing from the upregulation of the glutamine transporters in primary breast tumours, inhibition of glutamine uptake using small-molecule inhibitor V9302 reduced GD2+ cells by 70-80% and BCSC characteristics in TNBC cells. Mechanistic studies revealed inhibition of the mTOR pathway and induction of ferroptosis by V9302 in TNBC cells. Finally, inhibition of glutamine uptake significantly reduced in vivo tumour growth in a TNBC patient-derived xenograft model using NSG (non-obese diabetic/severe combined immunodeficiency with a complete null allele of the IL-2 receptor common gamma chain) mice. CONCLUSION Here, we show metabolic stress results in GD2+ BCSC phenotype in TNBC and glutamine contributes to GD2+ phenotype, and targeting the glutamine transporters could complement conventional chemotherapy in TNBC.
Collapse
Affiliation(s)
- Appalaraju Jaggupilli
- grid.240145.60000 0001 2291 4776Section of Molecular Hematology and Therapy, Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX USA
| | - Stanley Ly
- grid.240145.60000 0001 2291 4776Section of Molecular Hematology and Therapy, Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX USA
| | - Khoa Nguyen
- grid.240145.60000 0001 2291 4776Section of Molecular Hematology and Therapy, Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX USA
| | - Vivek Anand
- grid.240145.60000 0001 2291 4776Section of Molecular Hematology and Therapy, Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX USA
| | - Bin Yuan
- grid.240145.60000 0001 2291 4776Section of Molecular Hematology and Therapy, Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX USA
| | - Fouad El-Dana
- grid.240145.60000 0001 2291 4776Section of Molecular Hematology and Therapy, Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX USA
| | - Yuanqing Yan
- grid.468222.8Department of Neurosurgery, McGovern Medical School, The University of Texas Health Science Center, Houston, TX USA
| | - Zoe Arvanitis
- grid.240145.60000 0001 2291 4776Section of Molecular Hematology and Therapy, Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX USA
| | | | - Nagireddy Putluri
- grid.39382.330000 0001 2160 926XDepartment of Molecular and Cell Biology, Baylor College of Medicine, Houston, TX USA
| | - Helen Piwnica-Worms
- grid.240145.60000 0001 2291 4776Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX USA
| | - Henry Charles Manning
- grid.152326.10000 0001 2264 7217Center for Molecular Probes, Vanderbilt University Institute of Imaging Science, Nashville, TN USA
| | - Michael Andreeff
- grid.240145.60000 0001 2291 4776Section of Molecular Hematology and Therapy, Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX USA
| | - V. Lokesh Battula
- grid.240145.60000 0001 2291 4776Section of Molecular Hematology and Therapy, Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX USA ,grid.240145.60000 0001 2291 4776Section of Translational Breast Cancer Research, Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX USA
| |
Collapse
|
3
|
Mestril S, Kim R, Hinman SS, Gomez SM, Allbritton NL. Stem/Proliferative and Differentiated Cells within Primary Murine Colonic Epithelium Display Distinct Intracellular Free Ca 2+ Signal Codes. Adv Healthc Mater 2021; 10:e2101318. [PMID: 34510822 DOI: 10.1002/adhm.202101318] [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: 07/03/2021] [Revised: 08/24/2021] [Indexed: 11/11/2022]
Abstract
The second messenger, intracellular free calcium (Ca2+ ), acts to transduce mitogenic and differentiation signals incoming to the colonic epithelium. A self-renewing monolayer of primary murine colonic epithelial cells is formed over a soft, transparent hydrogel matrix for the scalable analysis of intracellular Ca2+ transients. Cultures that are enriched for stem/proliferative cells exhibit repetitive, high frequency (≈25 peaks h-1 ), and short pulse width (≈25 s) Ca2+ transients. Upon cell differentiation the transient frequency declines by 50% and pulse width widens by 200%. Metabolites and growth factors that are known to modulate stem cell proliferation and differentiation through Wnt and Notch signaling pathways, including CHIR-99021, N-[(3,5-Difluorophenyl)acetyl]-L-alanyl-2-phenylglycine-1,1-dimethylethyl ester (DAPT), bone morphogenetic proteins (BMPs), and butyrate, also modulate Ca2+ oscillation patterns in a consistent manner. Increasing the stiffness of the supportive matrix from 200 Pa to 3 GPa shifts Ca2+ transient patterns toward those resembling differentiated cells. The ability to monitor Ca2+ oscillations with the spatial and temporal resolution offered by this platform, combined with its amenability to high-content screens, provides a powerful tool for investigating real-time communication within a wide range of primary tissues in addition to the colonic epithelium.
Collapse
Affiliation(s)
- Sebastian Mestril
- Joint Department of Biomedical Engineering University of North Carolina at Chapel Hill and North Carolina State University Chapel Hill NC 27599 USA
| | - Raehyun Kim
- Department of Bioengineering University of Washington Seattle WA 98195 USA
| | - Samuel S. Hinman
- Department of Bioengineering University of Washington Seattle WA 98195 USA
| | - Shawn M. Gomez
- Joint Department of Biomedical Engineering University of North Carolina at Chapel Hill and North Carolina State University Chapel Hill NC 27599 USA
- Department of Pharmacology University of North Carolina at Chapel Hill Chapel Hill NC 27599 USA
| | | |
Collapse
|
4
|
Lu Y, Wang J, Soladoye OP, Aluko RE, Fu Y, Zhang Y. Preparation, receptors, bioactivity and bioavailability of γ-glutamyl peptides: A comprehensive review. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.04.051] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
5
|
Watkins JD, Koumanov F, Gonzalez JT. Protein- and Calcium-Mediated GLP-1 Secretion: A Narrative Review. Adv Nutr 2021; 12:2540-2552. [PMID: 34192748 PMCID: PMC8634310 DOI: 10.1093/advances/nmab078] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/31/2021] [Accepted: 05/25/2021] [Indexed: 02/06/2023] Open
Abstract
Glucagon-like peptide 1 (GLP-1) is an incretin hormone produced in the intestine that is secreted in response to nutrient exposure. GLP-1 potentiates glucose-dependent insulin secretion from the pancreatic β cells and promotes satiety. These important actions on glucose metabolism and appetite have led to widespread interest in GLP-1 receptor agonism. Typically, this involves pharmacological GLP-1 mimetics or targeted inhibition of dipeptidyl peptidase-IV, the enzyme responsible for GLP-1 degradation. However, nutritional strategies provide a widely available, cost-effective alternative to pharmacological strategies for enhancing hormone release. Recent advances in nutritional research have implicated the combined ingestion of protein and calcium with enhanced endogenous GLP-1 release, which is likely due to activation of receptors with high affinity and/or sensitivity for amino acids and calcium. Specifically targeting these receptors could enhance gut hormone secretion, thus providing a new therapeutic option. This narrative review provides an overview of the latest research on protein- and calcium-mediated GLP-1 release with an emphasis on human data, and a perspective on potential mechanisms that link potent GLP-1 release to the co-ingestion of protein and calcium. In light of these recent findings, potential future research directions are also presented.
Collapse
Affiliation(s)
- Jonathan D Watkins
- Centre for Nutrition, Exercise and Metabolism, Department for Health, University of Bath, Bath, United Kingdom
| | - Françoise Koumanov
- Centre for Nutrition, Exercise and Metabolism, Department for Health, University of Bath, Bath, United Kingdom
| | | |
Collapse
|
6
|
Lu VB, Gribble FM, Reimann F. Nutrient-Induced Cellular Mechanisms of Gut Hormone Secretion. Nutrients 2021; 13:nu13030883. [PMID: 33803183 PMCID: PMC8000029 DOI: 10.3390/nu13030883] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/27/2021] [Accepted: 03/05/2021] [Indexed: 02/06/2023] Open
Abstract
The gastrointestinal tract can assess the nutrient composition of ingested food. The nutrient-sensing mechanisms in specialised epithelial cells lining the gastrointestinal tract, the enteroendocrine cells, trigger the release of gut hormones that provide important local and central feedback signals to regulate nutrient utilisation and feeding behaviour. The evidence for nutrient-stimulated secretion of two of the most studied gut hormones, glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), along with the known cellular mechanisms in enteroendocrine cells recruited by nutrients, will be the focus of this review. The mechanisms involved range from electrogenic transporters, ion channel modulation and nutrient-activated G-protein coupled receptors that converge on the release machinery controlling hormone secretion. Elucidation of these mechanisms will provide much needed insight into postprandial physiology and identify tractable dietary approaches to potentially manage nutrition and satiety by altering the secreted gut hormone profile.
Collapse
|
7
|
Tuffour A, Kosiba AA, Zhang Y, Peprah FA, Gu J, Shi H. Role of the calcium-sensing receptor (CaSR) in cancer metastasis to bone: Identifying a potential therapeutic target. Biochim Biophys Acta Rev Cancer 2021; 1875:188528. [PMID: 33640382 DOI: 10.1016/j.bbcan.2021.188528] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 02/16/2021] [Accepted: 02/20/2021] [Indexed: 12/20/2022]
Abstract
Cancer is a major cause of morbidity and mortality worldwide due to its ability to evade immune surveillance and metastasize from its origin to a secondary point of contact. Though several treatment techniques have been developed to suppress or manage cancer spread, a strategy for total control over the disease continues to evade researchers. In considering ways to control or prevent cancer from metastasizing to the bone, we analyze the impact of the calcium-sensing receptor (CaSR), whose primary role is to maintain calcium (Ca2+) homeostasis in cellular and systemic physiological processes. CaSR is a pleiotropic receptor capable of enhancing the proliferation of some cancers such as breast, lung, prostate and kidney cancers at its primary site(s) and stimulating bone metastasis, while exerting a suppressive effect in others such as colon cancer. The activity of CaSR not only increases cancer cell proliferation, migration and suppression of apoptosis in the organs indicated, but also increases the secretion of parathyroid hormone-related protein (PTHrP) and epiregulin, which induce osteolytic activity and osteoblastic suppression. In addition, released cytokines and Ca2+ from bone resorption are critical factors that further promote cancer proliferation. In this review, we seek to highlight previous viewpoints on CaSR, discuss its role in a new context, and consider its potential clinical application in cancer treatment.
Collapse
Affiliation(s)
- Alex Tuffour
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
| | | | - Yao Zhang
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Frank Addai Peprah
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Jie Gu
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China
| | - Haifeng Shi
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
| |
Collapse
|
8
|
Aslam A, Ahmad J, Baghdadi MA, Idris S, Almaimani R, Alsaegh A, Alhadrami M, Refaat B. Chemopreventive effects of vitamin D 3 and its analogue, paricalcitol, in combination with 5-fluorouracil against colorectal cancer: The role of calcium signalling molecules. Biochim Biophys Acta Mol Basis Dis 2020; 1867:166040. [PMID: 33338596 DOI: 10.1016/j.bbadis.2020.166040] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 11/07/2020] [Accepted: 12/09/2020] [Indexed: 12/24/2022]
Abstract
BACKGROUND Although vitamin D (VD) is chemoprotective and enhances 5-fluorouracil (5-FU) cytotoxicity against colorectal cancer (CRC), little is known about its potential calcium (Ca2+)-mediated anti-tumorigenic actions. Therefore, this study compared between VD and its non-calcaemic analogue, Paricalcitol (Pcal), ± 5-FU in relation to chemoprevention and Ca2+-mediated apoptosis in vivo and in vitro. METHODS Seventy male mice were distributed to: negative controls, positive controls (PC), VD, Pcal, 5-FU, VD + 5-FU and Pcal+5-FU groups. All groups, except negative, received two consecutive azoxymethane (AOM)-injections (10 mg/Kg/week) for CRC induction. VD3 (1000 IU/kg; three times/week) and Pcal (1.25 μg/kg; three times/week) injections started week-16 post-AOM and for 10 weeks. Three successive 5-FU cycles began at week-21 (50 mg/Kg/week). Similar protocols with VD3, Pcal and/or 5-FU were applied in the HT29 colon cancer cells. RESULTS The PC group had abundant malignant tumours, markedly elevated proliferation markers (survivin/CCND1) and declines in cyclin-dependent kinase-inhibitor-1A, pro-apoptotic molecules (p53/BAX/cytochrome_C/caspase-3), tissue Ca2+ concentrations and Ca2+-dependent proteins (CaSR/CAM/CAMKIIA). All monotherapies equally reduced tumour numbers and proliferation markers whilst promoting the anti-tumorigenic molecules. VD and/or 5-FU, but not Pcal monotherapy, enhanced Ca2+ levels and Ca2+-related molecules (CaSR/CAM/CAMKIIA/BAX/cytochrome_C) in vivo and in vitro. However, VD + 5-FU co-therapy showed the lowest tumour numbers, the highest cell numbers in sub-G1 phase of cell cycle, alongside the most effective modulations of oncogenes, tumour suppressors and Ca2+-related molecules at the gene and protein levels in vivo and in vitro. CONCLUSIONS VD3 was superior than Paricalcitol in potentiating 5-FU cytotoxicity, possibly by upregulating several Ca2+-related molecules involved in tumour suppression.
Collapse
Affiliation(s)
- Akhmed Aslam
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al-Qura University, Al Abdeyah, PO Box 7607, Makkah, Saudi Arabia
| | - Jawwad Ahmad
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al-Qura University, Al Abdeyah, PO Box 7607, Makkah, Saudi Arabia
| | | | - Shakir Idris
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al-Qura University, Al Abdeyah, PO Box 7607, Makkah, Saudi Arabia
| | - Riyad Almaimani
- Department of Biochemistry, Faculty of Medicine, Umm Al-Qura University, Al Abdeyah, Makkah, Saudi Arabia
| | - Aiman Alsaegh
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al-Qura University, Al Abdeyah, PO Box 7607, Makkah, Saudi Arabia
| | - Mai Alhadrami
- Department of Pathology, Faculty of Medicine, Umm Al-Qura University, Al Abdeyah, Makkah, Saudi Arabia
| | - Bassem Refaat
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al-Qura University, Al Abdeyah, PO Box 7607, Makkah, Saudi Arabia.
| |
Collapse
|
9
|
|
10
|
Onopiuk M, Eby B, Nesin V, Ngo P, Lerner M, Gorvin CM, Stokes VJ, Thakker RV, Brandi ML, Chang W, Humphrey MB, Tsiokas L, Lau K. Control of PTH secretion by the TRPC1 ion channel. JCI Insight 2020; 5:132496. [PMID: 32213715 PMCID: PMC7205425 DOI: 10.1172/jci.insight.132496] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 03/16/2020] [Indexed: 11/17/2022] Open
Abstract
Familial hypocalciuric hypercalcemia (FHH) is a genetic condition associated with hypocalciuria, hypercalcemia, and, in some cases, inappropriately high levels of circulating parathyroid hormone (PTH). FHH is associated with inactivating mutations in the gene encoding the Ca2+-sensing receptor (CaSR), a GPCR, and GNA11 encoding G protein subunit α 11 (Gα11), implicating defective GPCR signaling as the root pathophysiology for FHH. However, the downstream mechanism by which CaSR activation inhibits PTH production/secretion is incompletely understood. Here, we show that mice lacking the transient receptor potential canonical channel 1 (TRPC1) develop chronic hypercalcemia, hypocalciuria, and elevated PTH levels, mimicking human FHH. Ex vivo and in vitro studies revealed that TRPC1 serves a necessary and sufficient mediator to suppress PTH secretion from parathyroid glands (PTGs) downstream of CaSR in response to high extracellular Ca2+ concentration. Gα11 physically interacted with both the N- and C-termini of TRPC1 and enhanced CaSR-induced TRPC1 activity in transfected cells. These data identify TRPC1-mediated Ca2+ signaling as an essential component of the cellular apparatus controlling PTH secretion in the PTG downstream of CaSR.
Collapse
Affiliation(s)
| | - Bonnie Eby
- Department of Medicine, Division of Nephrology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | | | | | - Megan Lerner
- Department of Surgery, Oklahoma City, Oklahoma, USA
| | - Caroline M Gorvin
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Victoria J Stokes
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Rajesh V Thakker
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Maria Luisa Brandi
- Department of Biomedicals Sperimentals and Clinicals Sciences, Università degli Studi di Firenze and Fondazione FIRMO, Florence, Italy
| | - Wenhan Chang
- Endocrinology and Metabolism, Department of Medicine, UCSF, San Francisco, California, USA
| | - Mary Beth Humphrey
- Department of Medicine, Division of Rheumatology, Immunology, and Allergy, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.,Department of Veterans Affairs, Oklahoma City, Oklahoma, USA
| | | | - Kai Lau
- Department of Medicine, Division of Nephrology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.,Department of Veterans Affairs, Oklahoma City, Oklahoma, USA
| |
Collapse
|
11
|
Elajnaf T, Iamartino L, Mesteri I, Müller C, Bassetto M, Manhardt T, Baumgartner-Parzer S, Kallay E, Schepelmann M. Nutritional and Pharmacological Targeting of the Calcium-Sensing Receptor Influences Chemically Induced Colitis in Mice. Nutrients 2019; 11:E3072. [PMID: 31888253 PMCID: PMC6950720 DOI: 10.3390/nu11123072] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 12/12/2019] [Accepted: 12/13/2019] [Indexed: 01/19/2023] Open
Abstract
The calcium-sensing receptor (CaSR) is the main regulator of extracellular Ca2+ homeostasis. It has diverse functions in different tissues, including the intestines. Intestine-specific knockout of the CaSR renders mice more susceptible to dextran sulphate sodium (DSS)-induced colitis. To test our hypothesis that the CaSR reduces intestinal inflammation, we assessed the effects of nutritional and pharmacological agonists of the CaSR in a colitis model. We treated female Balb/C mice with dietary calcium and protein (nutritional agonists of the CaSR) or pharmacological CaSR modulators (the agonists cinacalcet and GSK3004774, and the antagonist NPS-2143; 10 mg/kg), then induced colitis with DSS. The high-protein diet had a strong pro-inflammatory effect-it shortened the colons (5.3 ± 0.1 cm vs. 6.1 ± 0.2 cm normal diet, p < 0.05), lowered mucin expression and upregulated pro-inflammatory cytokines, such as interferon-γ, (4.2-fold, p < 0.05) compared with the normal diet. Cinacalcet reduced mucin expression, which coincided with an increase in tumor necrosis factor-α (4.4-fold, p < 0.05) and IL-6 (4.9-fold, p < 0.05) in the plasma, compared with vehicle. The CaSR antagonist, NPS-2143, significantly reduced the cumulative inflammation score compared with the vehicle control (35.3 ± 19.1 vs. 21.9 ± 14.3 area under the curve, p < 0.05) and reduced infiltration of inflammatory cells. While dietary modulation of the CaSR had no beneficial effects, pharmacological inhibition of the CaSR may have the potential of a novel add-on therapy in the treatment of inflammatory bowel diseases.
Collapse
Affiliation(s)
- Taha Elajnaf
- Center of Pathophysiology Infectiology and Immunology, Medical University of Vienna, Pathophysiology and Allergy Research, Währinger Gürtel, 18-20, 1090 Vienna, Austria; (T.E.); (L.I.); (C.M.); (T.M.); (M.S.)
| | - Luca Iamartino
- Center of Pathophysiology Infectiology and Immunology, Medical University of Vienna, Pathophysiology and Allergy Research, Währinger Gürtel, 18-20, 1090 Vienna, Austria; (T.E.); (L.I.); (C.M.); (T.M.); (M.S.)
| | | | - Christian Müller
- Center of Pathophysiology Infectiology and Immunology, Medical University of Vienna, Pathophysiology and Allergy Research, Währinger Gürtel, 18-20, 1090 Vienna, Austria; (T.E.); (L.I.); (C.M.); (T.M.); (M.S.)
| | - Marcella Bassetto
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, King Edward VII Avenue, CF10 3NB Cardiff, UK
- Department of Chemistry, College of Science, Swansea University, SA2 8PP Swansea, UK
| | - Teresa Manhardt
- Center of Pathophysiology Infectiology and Immunology, Medical University of Vienna, Pathophysiology and Allergy Research, Währinger Gürtel, 18-20, 1090 Vienna, Austria; (T.E.); (L.I.); (C.M.); (T.M.); (M.S.)
| | | | - Enikö Kallay
- Center of Pathophysiology Infectiology and Immunology, Medical University of Vienna, Pathophysiology and Allergy Research, Währinger Gürtel, 18-20, 1090 Vienna, Austria; (T.E.); (L.I.); (C.M.); (T.M.); (M.S.)
| | - Martin Schepelmann
- Center of Pathophysiology Infectiology and Immunology, Medical University of Vienna, Pathophysiology and Allergy Research, Währinger Gürtel, 18-20, 1090 Vienna, Austria; (T.E.); (L.I.); (C.M.); (T.M.); (M.S.)
| |
Collapse
|
12
|
Yang X, Lou J, Shan W, Hu Y, Du Q, Liao Q, Xie R, Xu J. Pathogenic roles of altered calcium channels and transporters in colon tumorogenesis. Life Sci 2019; 239:116909. [DOI: 10.1016/j.lfs.2019.116909] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/12/2019] [Accepted: 09/23/2019] [Indexed: 01/26/2023]
|
13
|
Barry EL, Lund JL, Westreich D, Mott LA, Ahnen DJ, Beck GJ, Bostick RM, Bresalier RS, Burke CA, Church TR, Rees JR, Robertson DJ, Baron JA. Body mass index, calcium supplementation and risk of colorectal adenomas. Int J Cancer 2018; 144:448-458. [PMID: 30117164 DOI: 10.1002/ijc.31803] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 07/25/2018] [Accepted: 07/27/2018] [Indexed: 12/20/2022]
Abstract
Calcium supplementation (1,200 mg/day) did not significantly reduce colorectal adenomas in our recent randomized, controlled trial (Vitamin D/Calcium Polyp Prevention Study, VCPPS, 2004-2013) in contrast to our previous trial (Calcium Polyp Prevention Study, CPPS, 1988-1996). To reconcile these findings, we identified participant characteristics that differed between the study populations and modified the effect of calcium supplementation on adenomas or high-risk findings (advanced or multiple adenomas). Compared to the CPPS, more participants in the VCPPS were obese (body mass index (BMI) ≥30 kg/m2 ; 37.5% vs. 24.4%) and fewer had normal BMI (BMI <25 kg/m2 ; 18.5% vs. 31%). BMI appeared to modify the effect of calcium supplementation on adenomas and especially on high risk-findings: in the VCPPS, there was a 44% reduction in high-risk findings among individuals whose BMI was normal (RR = 0.56, 95% CI = 0.26-1.23), but not among overweight (RR = 1.09, 95% CI = 0.62-1.91) or obese (RR = 1.54, 95% CI = 0.92-2.57) individuals (pinteraction = 0.03). Similarly, in the CPPS, there was a 56% reduction in high-risk findings among individuals whose BMI was normal (RR = 0.44, 95% CI = 0.26-0.74), but not among overweight (RR = 0.87, 95% CI = 0.55-1.39) or obese (RR = 1.02, 95% CI = 0.57-1.82) individuals (pinteraction = 0.02). Standardization of each trial's findings to the BMI distribution in the other attenuated calcium's protective effect on adenomas in the CPPS but enhanced it in the VCPPS. In conclusion, 1,200 mg/day calcium supplementation may reduce risk of colorectal adenomas among those with normal BMI but not in overweight or obese individuals; and differences in BMI distribution partially account for the apparent difference in calcium efficacy between the two trials.
Collapse
Affiliation(s)
- Elizabeth L Barry
- Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Jennifer L Lund
- Department of Epidemiology, University of North Carolina at Chapel Hill, Gillings School of Public Health, Chapel Hill, NC
| | - Daniel Westreich
- Department of Epidemiology, University of North Carolina at Chapel Hill, Gillings School of Public Health, Chapel Hill, NC
| | - Leila A Mott
- Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Dennis J Ahnen
- Division of Gastroenterology and Hepatology, University of Colorado School of Medicine, Denver, CO
| | - Gerald J Beck
- Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH
| | - Roberd M Bostick
- Department of Epidemiology, Rollins School of Public Health, Emory University and Winship Cancer Institute, Atlanta, GA
| | - Robert S Bresalier
- Department of Gastroenterology, Hepatology, and Nutrition, University of Texas M.D. Anderson Cancer Center, Houston, TX
| | - Carol A Burke
- Department of Gastroenterology and Hepatology, Cleveland Clinic, Cleveland, OH
| | - Timothy R Church
- Division of Environmental Health Sciences, University of Minnesota School of Public Health, Minneapolis, MN
| | - Judy R Rees
- Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Douglas J Robertson
- VA Medical Center, White River Junction, VT and Geisel School of Medicine at Dartmouth, Hanover, NH
| | - John A Baron
- Department of Epidemiology, Geisel School of Medicine at Dartmouth, Lebanon, NH.,Department of Epidemiology, University of North Carolina at Chapel Hill, Gillings School of Public Health, Chapel Hill, NC.,Department of Medicine, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC
| |
Collapse
|
14
|
Iamartino L, Elajnaf T, Kallay E, Schepelmann M. Calcium-sensing receptor in colorectal inflammation and cancer: Current insights and future perspectives. World J Gastroenterol 2018; 24:4119-4131. [PMID: 30271078 PMCID: PMC6158479 DOI: 10.3748/wjg.v24.i36.4119] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/11/2018] [Accepted: 08/01/2018] [Indexed: 02/06/2023] Open
Abstract
The extracellular calcium-sensing receptor (CaSR) is best known for its action in the parathyroid gland and kidneys where it controls body calcium homeostasis. However, the CaSR has different roles in the gastrointestinal tract, where it is ubiquitously expressed. In the colon, the CaSR is involved in controlling multiple mechanisms, including fluid transport, inflammation, cell proliferation and differentiation. Although the expression pattern and functions of the CaSR in the colonic microenvironment are far from being completely understood, evidence has been accumulating that the CaSR might play a protective role against both colonic inflammation and colorectal cancer. For example, CaSR agonists such as dipeptides have been suggested to reduce colonic inflammation, while dietary calcium was shown to reduce the risk of colorectal cancer. CaSR expression is lost in colonic malignancies, indicating that the CaSR is a biomarker for colonic cancer progression. This dual anti-inflammatory and anti-tumourigenic role of the CaSR makes it especially interesting in colitis-associated colorectal cancer. In this review, we describe the clinical and experimental evidence for the role of the CaSR in colonic inflammation and colorectal cancer, the intracellular signalling pathways which are putatively involved in these actions, and the possibilities to exploit these actions of the CaSR for future therapies of colonic inflammation and cancer.
Collapse
Affiliation(s)
- Luca Iamartino
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna 1090, Austria
| | - Taha Elajnaf
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna 1090, Austria
| | - Enikö Kallay
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna 1090, Austria
| | - Martin Schepelmann
- Institute of Pathophysiology and Allergy Research, Medical University of Vienna, Vienna 1090, Austria
| |
Collapse
|
15
|
Jain RA, Wolman MA, Marsden KC, Nelson JC, Shoenhard H, Echeverry FA, Szi C, Bell H, Skinner J, Cobbs EN, Sawada K, Zamora AD, Pereda AE, Granato M. A Forward Genetic Screen in Zebrafish Identifies the G-Protein-Coupled Receptor CaSR as a Modulator of Sensorimotor Decision Making. Curr Biol 2018; 28:1357-1369.e5. [PMID: 29681477 DOI: 10.1016/j.cub.2018.03.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 01/24/2018] [Accepted: 03/13/2018] [Indexed: 12/26/2022]
Abstract
Animals continuously integrate sensory information and select contextually appropriate responses. Here, we show that zebrafish larvae select a behavioral response to acoustic stimuli from a pre-existing choice repertoire in a context-dependent manner. We demonstrate that this sensorimotor choice is modulated by stimulus quality and history, as well as by neuromodulatory systems-all hallmarks of more complex decision making. Moreover, from a genetic screen coupled with whole-genome sequencing, we identified eight mutants with deficits in this sensorimotor choice, including mutants of the vertebrate-specific G-protein-coupled extracellular calcium-sensing receptor (CaSR), whose function in the nervous system is not well understood. We demonstrate that CaSR promotes sensorimotor decision making acutely through Gαi/o and Gαq/11 signaling, modulated by clathrin-mediated endocytosis. Combined, our results identify the first set of genes critical for behavioral choice modulation in a vertebrate and reveal an unexpected critical role for CaSR in sensorimotor decision making.
Collapse
Affiliation(s)
- Roshan A Jain
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biology, Haverford College, Haverford, PA 19041, USA.
| | - Marc A Wolman
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kurt C Marsden
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jessica C Nelson
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hannah Shoenhard
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Fabio A Echeverry
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Rose F. Kennedy Center, 1410 Pelham Parkway South, Bronx, NY 10461, USA
| | - Christina Szi
- Department of Biology, Haverford College, Haverford, PA 19041, USA
| | - Hannah Bell
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Julianne Skinner
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Emilia N Cobbs
- Department of Biology, Haverford College, Haverford, PA 19041, USA
| | - Keisuke Sawada
- Department of Biology, Haverford College, Haverford, PA 19041, USA
| | - Amy D Zamora
- Department of Biology, Haverford College, Haverford, PA 19041, USA
| | - Alberto E Pereda
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Rose F. Kennedy Center, 1410 Pelham Parkway South, Bronx, NY 10461, USA
| | - Michael Granato
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
16
|
Gerbino A, Colella M. The Different Facets of Extracellular Calcium Sensors: Old and New Concepts in Calcium-Sensing Receptor Signalling and Pharmacology. Int J Mol Sci 2018; 19:E999. [PMID: 29584660 PMCID: PMC5979557 DOI: 10.3390/ijms19040999] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 03/23/2018] [Accepted: 03/25/2018] [Indexed: 12/14/2022] Open
Abstract
The current interest of the scientific community for research in the field of calcium sensing in general and on the calcium-sensing Receptor (CaR) in particular is demonstrated by the still increasing number of papers published on this topic. The extracellular calcium-sensing receptor is the best-known G-protein-coupled receptor (GPCR) able to sense external Ca2+ changes. Widely recognized as a fundamental player in systemic Ca2+ homeostasis, the CaR is ubiquitously expressed in the human body where it activates multiple signalling pathways. In this review, old and new notions regarding the mechanisms by which extracellular Ca2+ microdomains are created and the tools available to measure them are analyzed. After a survey of the main signalling pathways triggered by the CaR, a special attention is reserved for the emerging concepts regarding CaR function in the heart, CaR trafficking and pharmacology. Finally, an overview on other Ca2+ sensors is provided.
Collapse
Affiliation(s)
- Andrea Gerbino
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari, 70121 Bari, Italy.
| | - Matilde Colella
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari, 70121 Bari, Italy.
| |
Collapse
|
17
|
Ca 2+ protein alpha 1D of CaV1.3 regulates intracellular calcium concentration and migration of colon cancer cells through a non-canonical activity. Sci Rep 2017; 7:14199. [PMID: 29079724 PMCID: PMC5660277 DOI: 10.1038/s41598-017-14230-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 10/03/2017] [Indexed: 01/05/2023] Open
Abstract
It is generally accepted that voltage-gated Ca2+ channels, CaV, regulate Ca2+ homeostasis in excitable cells following plasma membrane depolarization. Here, we show that the Ca2+ protein α1D of CaV1.3 channel is overexpressed in colorectal cancer biopsies compared to normal tissues. Gene silencing experiments targeting α1D reduced the migration and the basal cytosolic Ca2+ concentration of HCT116 colon cancer cell line and modified the cytosolic Ca2+ oscillations induced by the sodium/calcium exchanger NCX1/3 working in its reverse mode. Interestingly, NCX1/3 regulated membrane potential of HCT116 cells only when α1D was silenced, and blocking NCX1/3 increased cytosolic Ca2+ concentration and cell migration. However, membrane depolarization did not induce an increase in intracellular Ca2+. Patch-clamp experiments clearly showed that the inward Ca2+ current was absent. Finally, flow cytometry and immunofluorescence studies showed that α1D protein was localized at the plasma membrane, in cytosol and cell nuclei. Altogether, we uncover a novel signaling pathway showing that α1D is involved in the regulation of Ca2+ homeostasis and cell migration by a mechanism independent of its plasma membrane canonical function but that involved plasma membrane Na+/Ca2+ exchanger.
Collapse
|
18
|
Momen-Heravi F, Masugi Y, Qian ZR, Nishihara R, Liu L, Smith-Warner SA, Keum N, Zhang L, Tchrakian N, Nowak JA, Yang W, Ma Y, Bowden M, da Silva A, Wang M, Fuchs CS, Meyerhardt JA, Ng K, Wu K, Giovannucci E, Ogino S, Zhang X. Tumor expression of calcium sensing receptor and colorectal cancer survival: Results from the nurses' health study and health professionals follow-up study. Int J Cancer 2017; 141:2471-2479. [PMID: 28856682 DOI: 10.1002/ijc.31021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 07/16/2017] [Accepted: 08/01/2017] [Indexed: 12/11/2022]
Abstract
Although experimental evidence suggests calcium-sensing receptor (CASR) as a tumor-suppressor, the prognostic role of tumor CASR expression in colorectal carcinoma remains unclear. We hypothesized that higher tumor CASR expression might be associated with improved survival among colorectal cancer patients. We evaluated tumor expression levels of CASR by immunohistochemistry in 809 incident colorectal cancer patients within the Nurses' Health Study and the Health Professionals Follow-up Study. We used Cox proportional hazards regression models to estimate multivariable hazard ratio (HR) for the association of tumor CASR expression with colorectal cancer-specific and all-cause mortality. We adjusted for potential confounders including tumor biomarkers such as microsatellite instability, CpG island methylator phenotype, LINE-1 methylation level, expressions of PTGS2, VDR and CTNNB1 and mutations of KRAS, BRAF and PIK3CA. There were 240 colorectal cancer-specific deaths and 427 all-cause deaths. The median follow-up of censored patients was 10.8 years (interquartile range: 7.2, 15.1). Compared with patients with no or weak expression of CASR, the multivariable HRs for colorectal cancer-specific mortality were 0.80 [95% confidence interval (CI): 0.55-1.16] in patients with moderate CASR expression and 0.50 (95% CI: 0.32-0.79) in patients with intense CASR expression (p-trend = 0.003). The corresponding HRs for overall mortality were 0.85 (0.64-1.13) and 0.81 (0.58-1.12), respectively. Higher tumor CASR expression was associated with a lower risk of colorectal cancer-specific mortality. This finding needs further confirmation and if confirmed, may lead to better understanding of the role of CASR in colorectal cancer progression.
Collapse
Affiliation(s)
- Fatemeh Momen-Heravi
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,Division of Periodontics, Section of Oral, Diagnostic and Rehabilitation Sciences, College of Dental Medicine, Columbia University, New York, NY
| | - Yohei Masugi
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Zhi Rong Qian
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Reiko Nishihara
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA.,Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Food Science and Biotechnology, Dongguk University, Goyang, South Korea.,Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Pathology, Program in MPE Molecular Pathological Epidemiology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
| | - Li Liu
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA.,Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Food Science and Biotechnology, Dongguk University, Goyang, South Korea.,Department of Epidemiology and Biostatistics, and the Ministry of Education Key Lab of Environment and Health, School of Public Health, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Stephanie A Smith-Warner
- Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Food Science and Biotechnology, Dongguk University, Goyang, South Korea.,Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA
| | - NaNa Keum
- Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Food Science and Biotechnology, Dongguk University, Goyang, South Korea
| | - Lanjing Zhang
- Department of Pathology, University Medical Center of Princeton, Plainsboro, NJ.,Department of Biological Sciences, Rutgers University, Newark, NJ.,Clinical Investigations and Precision Therapeutics Research Program, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ.,Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ
| | - Nairi Tchrakian
- Department of Pathology, St James's Hospital, Dublin, Ireland
| | - Jonathan A Nowak
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA.,Department of Pathology, Program in MPE Molecular Pathological Epidemiology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
| | - Wanshui Yang
- Department of Social Science and Public Health, School of Basic Medical Science, Jiujiang University, Jiujiang, People's Republic of China
| | - Yanan Ma
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,Department of Biostatistics and Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning, People's Republic of China
| | - Michaela Bowden
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Annacarolina da Silva
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA.,Department of Oncologic Pathology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Molin Wang
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA
| | - Charles S Fuchs
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,Division of Periodontics, Section of Oral, Diagnostic and Rehabilitation Sciences, College of Dental Medicine, Columbia University, New York, NY.,Yale Cancer Center & Smilow Cancer Hospital, New Haven, CT.,Department of Medicine, Yale School of Medicine, New Haven, CT
| | - Jeffrey A Meyerhardt
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Kimmie Ng
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Kana Wu
- Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Food Science and Biotechnology, Dongguk University, Goyang, South Korea
| | - Edward Giovannucci
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Food Science and Biotechnology, Dongguk University, Goyang, South Korea
| | - Shuji Ogino
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA.,Department of Pathology, Program in MPE Molecular Pathological Epidemiology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,Department of Oncologic Pathology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
| | - Xuehong Zhang
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA
| |
Collapse
|
19
|
Sparks SM, Spearing PK, Diaz CJ, Cowan DJ, Jayawickreme C, Chen G, Rimele TJ, Generaux C, Harston LT, Roller SG. Identification of potent, nonabsorbable agonists of the calcium-sensing receptor for GI-specific administration. Bioorg Med Chem Lett 2017; 27:4673-4677. [PMID: 28916340 DOI: 10.1016/j.bmcl.2017.09.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 08/25/2017] [Accepted: 09/06/2017] [Indexed: 12/14/2022]
Abstract
Modulation of gastrointestinal nutrient sensing pathways provides a promising a new approach for the treatment of metabolic diseases including diabetes and obesity. The calcium-sensing receptor has been identified as a key receptor involved in mineral and amino acid nutrient sensing and thus is an attractive target for modulation in the intestine. Herein we describe the optimization of gastrointestinally restricted calcium-sensing receptor agonists starting from a 3-aminopyrrolidine-containing template leading to the identification of GI-restricted agonist 19 (GSK3004774).
Collapse
Affiliation(s)
- Steven M Sparks
- Enteroendocrine Discovery Performance Unit and Platform Technologies and Science, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, United States.
| | - Paul K Spearing
- Enteroendocrine Discovery Performance Unit and Platform Technologies and Science, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, United States
| | - Caroline J Diaz
- Enteroendocrine Discovery Performance Unit and Platform Technologies and Science, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, United States
| | - David J Cowan
- Enteroendocrine Discovery Performance Unit and Platform Technologies and Science, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, United States
| | - Channa Jayawickreme
- Enteroendocrine Discovery Performance Unit and Platform Technologies and Science, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, United States
| | - Grace Chen
- Enteroendocrine Discovery Performance Unit and Platform Technologies and Science, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, United States
| | - Thomas J Rimele
- Enteroendocrine Discovery Performance Unit and Platform Technologies and Science, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, United States
| | - Claudia Generaux
- Enteroendocrine Discovery Performance Unit and Platform Technologies and Science, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, United States
| | - Lindsey T Harston
- Enteroendocrine Discovery Performance Unit and Platform Technologies and Science, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, United States
| | - Shane G Roller
- Enteroendocrine Discovery Performance Unit and Platform Technologies and Science, GlaxoSmithKline, 5 Moore Drive, Research Triangle Park, NC 27709, United States
| |
Collapse
|
20
|
The Control of Calcium Metabolism in Zebrafish (Danio rerio). Int J Mol Sci 2016; 17:ijms17111783. [PMID: 27792163 PMCID: PMC5133784 DOI: 10.3390/ijms17111783] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 10/18/2016] [Accepted: 10/19/2016] [Indexed: 12/19/2022] Open
Abstract
Zebrafish is an emerging model for the research of body fluid ionic homeostasis. In this review, we focus on current progress on the regulation of Ca2+ uptake in the context of Ca2+ sensing and hormonal regulation in zebrafish. Na⁺-K⁺-ATPase-rich cells (NaRCs), the specialized ionocytes in the embryonic skin and adult gills, play a dominant role in Ca2+ uptake in zebrafish. Transepithelial Ca2+ transport in NaRC, through apical epithelial Ca2+ channels (ECaC), basolateral plasma membrane Ca2+-ATPase (PMCA), and Na⁺/Ca2+ exchanger (NCX), is analogous to mammalian renal and intestinal Ca2+-absorption cells. Several hormones were demonstrated to differentially regulate Ca2+ uptake through modulating the expression of Ca2+ transporters and/or the proliferation/differentiation of NaRC in zebrafish. In addition, the counterbalance among these hormones is associated with the maintenance of body fluid Ca2+ homeostasis. Calcium-sensing receptor (CaSR) is expressed in several hormone-secreting tissues in zebrafish, and activated CaSR differentially controls calciotropic hormones. The major principles of Ca2+ transport and the hormonal control appear to be conserved from zebrafish to other vertebrates including mammals. The new knowledge gained from zebrafish studies provides new insights into the related issues in vertebrates.
Collapse
|
21
|
Díaz-Soto G, Rocher A, García-Rodríguez C, Núñez L, Villalobos C. The Calcium-Sensing Receptor in Health and Disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 327:321-369. [PMID: 27692178 DOI: 10.1016/bs.ircmb.2016.05.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The extracellular calcium-sensing receptor (CaSR) is a unique G protein-coupled receptor (GPCR) activated by extracellular Ca2+ and by other physiological cations including Mg2+, amino acids, and polyamines. CaSR is the most important master controller of the extracellular Ca2+ homeostatic system being expressed at high levels in the parathyroid gland, kidney, gut and bone, where it regulates parathyroid hormone (PTH) secretion, vitamin D synthesis, and Ca2+ absorption and resorption, respectively. Gain and loss of function mutations in the CaSR are responsible for severe disturbances in extracellular Ca2+ metabolism. CaSR agonists (calcimimetics) and antagonists (calcilytics) are in use or under intense research for treatment of hyperparathyroidism secondary to kidney failure and hypocalcemia with hypercalciuria, respectively. Expression of the CaSR extends to other tissues and systems beyond the extracellular Ca2+ homeostatic system including the cardiovascular system, the airways, and the nervous system where it may play physiological functions yet to be fully understood. As a consequence, CaSR has been recently involved in different pathologies including uncontrolled blood pressure, vascular calcification, asthma, and Alzheimer's disease. Finally, the CaSR has been shown to play a critical role in cancer either contributing to bone metastasis and/or acting as a tumor suppressor in some forms of cancer (parathyroid cancer, colon cancer, and neuroblastoma) and as oncogene in others (breast and prostate cancers). Here we review the role of CaSR in health and disease in calciotropic tissues and others beyond the extracellular calcium homeostatic system.
Collapse
Affiliation(s)
- G Díaz-Soto
- Endocrinology and Nutrition, Valladolid University Hospital, Valladolid, Spain
| | - A Rocher
- Department of Biochemistry and Molecular Biology and Physiology, University of Valladolid, Valladolid, Spain; Institute of Molecular Biology and Genetics (IBGM), University of Valladolid and National Research Council (CSIC), Valladolid, Spain
| | - C García-Rodríguez
- Institute of Molecular Biology and Genetics (IBGM), University of Valladolid and National Research Council (CSIC), Valladolid, Spain
| | - L Núñez
- Department of Biochemistry and Molecular Biology and Physiology, University of Valladolid, Valladolid, Spain; Institute of Molecular Biology and Genetics (IBGM), University of Valladolid and National Research Council (CSIC), Valladolid, Spain
| | - C Villalobos
- Institute of Molecular Biology and Genetics (IBGM), University of Valladolid and National Research Council (CSIC), Valladolid, Spain.
| |
Collapse
|
22
|
Enhanced Proliferation of Porcine Bone Marrow Mesenchymal Stem Cells Induced by Extracellular Calcium is Associated with the Activation of the Calcium-Sensing Receptor and ERK Signaling Pathway. Stem Cells Int 2016; 2016:6570671. [PMID: 27123007 PMCID: PMC4829725 DOI: 10.1155/2016/6570671] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Revised: 03/02/2016] [Accepted: 03/17/2016] [Indexed: 12/22/2022] Open
Abstract
Porcine bone marrow mesenchymal stem cells (pBMSCs) have the potential for application in regenerative medicine. This study aims to investigate the effects of extracellular calcium ([Ca2+]o) on pBMSCs proliferation and to explore the possible underlying mechanisms. The results demonstrated that 4 mM [Ca2+]o significantly promoted pBMSCs proliferation by reducing the G0/G1 phase cell percentage and by increasing the S phase cell proportion and the proliferation index of pBMSCs. Accordingly, [Ca2+]o stimulated the expression levels of proliferative genes such as cyclin A2, cyclin D1/3, cyclin E2, and PCNA and inhibited the expression of p21. In addition, [Ca2+]o resulted in a significant elevation of intracellular calcium and an increased ratio of p-ERK/ERK. However, inhibition of calcium-sensing receptor (CaSR) by its antagonist NPS2143 abolished the aforementioned effects of [Ca2+]o. Moreover, [Ca2+]o-induced promotion of pBMSCs proliferation, the changes of proliferative genes expression levels, and the activation of ERK1/2 signaling pathway were effectively blocked by U0126, a selective ERK kinase inhibitor. In conclusion, our findings provided evidence that the enhanced pBMSCs proliferation in response to [Ca2+]o was associated with the activation of CaSR and ERK1/2 signaling pathway, which may be useful for the application of pBMSCs in future clinical studies aimed at tissue regeneration and repair.
Collapse
|
23
|
Owen JL, Cheng SX, Ge Y, Sahay B, Mohamadzadeh M. The role of the calcium-sensing receptor in gastrointestinal inflammation. Semin Cell Dev Biol 2015; 49:44-51. [PMID: 26709005 DOI: 10.1016/j.semcdb.2015.10.040] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 10/28/2015] [Accepted: 10/29/2015] [Indexed: 12/13/2022]
Abstract
The gastrointestinal (GI) tract must balance the extraction of energy and metabolic end-products from ingested nutrition and resident gut microbes and the maintenance of a symbiotic relationship with this microbiota, with the ability to mount functional immune responses to pathogenic organisms to maintain GI health. The gut epithelium is equipped with bacteria-sensing mechanisms that discriminate between pathogenic and commensal microorganisms and regulate host responses between immunity and tolerance. The epithelium also expresses numerous nutrient-sensing receptors, but their importance in the preservation of the gut microbiota and immune homeostasis remains largely unexplored. Observations that a deficiency in the extracellular calcium-sensing receptor (CaSR) using intestinal epithelium-specific receptor knockout mice resulted in diminished intestinal barrier integrity, altered composition of the gut microbiota, modified expression of intestinal pattern recognition receptors, and a skewing of local and systemic innate responses from regulatory to stimulatory, may change the way that this receptor is considered as a potential immunotherapeutic target in gut homeostasis. These findings suggest that pharmacologic CaSR activators and CaSR-based nutrients such as calcium, polyamines, phenylalanine, tryptophan, and oligo-peptides might be useful in conditioning the gut microenvironment, and thus, in the prevention and treatment of disorders such as inflammatory bowel disease (IBD), infectious enterocolitis, and other inflammatory and secretory diarrheal diseases. Here, we review the emerging roles of the CaSR in intestinal homeostasis and its therapeutic potential for gut pathology.
Collapse
Affiliation(s)
- Jennifer L Owen
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
| | - Sam X Cheng
- Division of Gastroenterology, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Yong Ge
- Department of Infectious Diseases and Pathology, University of Florida, Gainesville, FL, USA; Division of Hepatology, Gastroenterology, and Nutrition, University of Florida, Gainesville, FL, USA
| | - Bikash Sahay
- Department of Infectious Diseases and Pathology, University of Florida, Gainesville, FL, USA; Division of Hepatology, Gastroenterology, and Nutrition, University of Florida, Gainesville, FL, USA
| | - Mansour Mohamadzadeh
- Department of Infectious Diseases and Pathology, University of Florida, Gainesville, FL, USA; Division of Hepatology, Gastroenterology, and Nutrition, University of Florida, Gainesville, FL, USA.
| |
Collapse
|
24
|
Tirupula KC, Ithychanda SS, Mohan ML, Naga Prasad SV, Qin J, Karnik SS. G protein-coupled receptors directly bind filamin A with high affinity and promote filamin phosphorylation. Biochemistry 2015; 54:6673-83. [PMID: 26460884 PMCID: PMC4642222 DOI: 10.1021/acs.biochem.5b00975] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Although interaction of a few G protein-coupled receptors (GPCRs) with Filamin A, a key actin cross-linking and biomechanical signal transducer protein, has been observed, a comprehensive structure-function analysis of this interaction is lacking. Through a systematic sequence-based analysis, we found that a conserved filamin binding motif is present in the cytoplasmic domains of >20% of the 824 GPCRs encoded in the human genome. Direct high-affinity interaction of filamin binding motif peptides of select GPCRs with the Ig domain of Filamin A was confirmed by nuclear magnetic resonance spectroscopy and isothermal titration calorimetric experiments. Engagement of the filamin binding motif with the Filamin A Ig domain induced the phosphorylation of filamin by protein kinase A in vitro. In transfected cells, agonist activation as well as constitutive activation of representative GPCRs dramatically elicited recruitment and phosphorylation of cellular Filamin A, a phenomenon long known to be crucial for regulating the structure and dynamics of the cytoskeleton. Our data suggest a molecular mechanism for direct GPCR-cytoskeleton coupling via filamin. Until now, GPCR signaling to the cytoskeleton was predominantly thought to be indirect, through canonical G protein-mediated signaling cascades involving GTPases, adenylyl cyclases, phospholipases, ion channels, and protein kinases. We propose that the GPCR-induced filamin phosphorylation pathway is a conserved, novel biochemical signaling paradigm.
Collapse
Affiliation(s)
- Kalyan C Tirupula
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic , Cleveland, Ohio 44195, United States
| | - Sujay S Ithychanda
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic , Cleveland, Ohio 44195, United States
| | - Maradumane L Mohan
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic , Cleveland, Ohio 44195, United States
| | - Sathyamangla V Naga Prasad
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic , Cleveland, Ohio 44195, United States
| | - Jun Qin
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic , Cleveland, Ohio 44195, United States
| | - Sadashiva S Karnik
- Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic , Cleveland, Ohio 44195, United States
| |
Collapse
|
25
|
Young SH, Rey O, Rozengurt E. Intracellular Ca(2+) oscillations generated via the extracellular Ca(2+)-sensing receptor (CaSR) in response to extracellular Ca(2+) or L-phenylalanine: Impact of the highly conservative mutation Ser170Thr. Biochem Biophys Res Commun 2015; 467:1-6. [PMID: 26431875 DOI: 10.1016/j.bbrc.2015.09.144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 09/26/2015] [Indexed: 12/21/2022]
Abstract
The extracellular Ca(2+)-sensing receptor (CaSR) is an allosteric protein that responds to changes in the extracellular concentration of Ca(2+) ([Ca(2+)]e) and aromatic amino acids with the production of different patterns of oscillations in intracellular Ca(2+) concentration ([Ca(2+)]i). An increase in [Ca(2+)]e stimulates sinusoidal oscillations in [Ca(2+)]i whereas aromatic amino acid-induced CaR activation in the presence of a threshold [Ca(2+)]e promotes transient oscillations in [Ca(2+)]i. Here, we examined spontaneous and ligand-evoked [Ca(2+)]i oscillations in single HEK-293 cells transfected with the wild type CaSR or with a mutant CaSR in which Ser170 was converted to Thr (CaSRS170T). Our analysis demonstrates that cells expressing CaSRS170T display [Ca(2+)]i oscillations in the presence of low concentrations of extracellular Ca(2+) and respond to L-Phe with robust transient [Ca(2+)]i oscillations. Our results indicate that the S170T mutation induces a marked increase in CaSR sensitivity to [Ca(2+)]e and imply that the allosteric regulation of the CaSR by aromatic amino acids is not only mediated by an heterotropic positive effect on Ca(2+) binding cooperativity but, as biased agonists, aromatic amino acids stabilize a CaSR conformation that couples to a different signaling pathway leading to transient [Ca(2+)]i oscillations.
Collapse
Affiliation(s)
- Steven H Young
- Division of Digestive Diseases, Department of Medicine, CURE: Digestive Diseases Research Center, David Geffen School of Medicine and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Osvaldo Rey
- Institute of Immunology, Genetics and Metabolism, Consejo Nacional de Investigaciones Cientificas y Tecnicas, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Enrique Rozengurt
- Division of Digestive Diseases, Department of Medicine, CURE: Digestive Diseases Research Center, David Geffen School of Medicine and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, CA 90095, USA; Veterans Affairs West Los Angeles Healthcare System, Los Angeles, CA, USA.
| |
Collapse
|
26
|
IGFBP-2: The dark horse in metabolism and cancer. Cytokine Growth Factor Rev 2015; 26:329-46. [DOI: 10.1016/j.cytogfr.2014.12.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 12/09/2014] [Indexed: 12/29/2022]
|
27
|
Cook AE, Mistry SN, Gregory KJ, Furness SGB, Sexton PM, Scammells PJ, Conigrave AD, Christopoulos A, Leach K. Biased allosteric modulation at the CaS receptor engendered by structurally diverse calcimimetics. Br J Pharmacol 2015; 172:185-200. [PMID: 25220431 PMCID: PMC4280977 DOI: 10.1111/bph.12937] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 09/02/2014] [Accepted: 09/07/2014] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND AND PURPOSE Clinical use of cinacalcet in hyperparathyroidism is complicated by its tendency to induce hypocalcaemia, arising partly from activation of calcium-sensing receptors (CaS receptors) in the thyroid and stimulation of calcitonin release. CaS receptor allosteric modulators that selectively bias signalling towards pathways that mediate desired effects [e.g. parathyroid hormone (PTH) suppression] rather than those mediating undesirable effects (e.g. elevated serum calcitonin), may offer better therapies. EXPERIMENTAL APPROACH We characterized the ligand-biased profile of novel calcimimetics in HEK293 cells stably expressing human CaS receptors, by monitoring intracellular calcium (Ca(2+) i ) mobilization, inositol phosphate (IP)1 accumulation, ERK1/2 phosphorylation (pERK1/2) and receptor expression. KEY RESULTS Phenylalkylamine calcimimetics were biased towards allosteric modulation of Ca(2+) i mobilization and IP1 accumulation. S,R-calcimimetic B was biased only towards IP1 accumulation. R,R-calcimimetic B and AC-265347 were biased towards IP1 accumulation and pERK1/2. Nor-calcimimetic B was unbiased. In contrast to phenylalkylamines and calcimimetic B analogues, AC-265347 did not promote trafficking of a loss-of-expression, naturally occurring, CaS receptor mutation (G(670) E). CONCLUSIONS AND IMPLICATIONS The ability of R,R-calcimimetic B and AC-265347 to bias signalling towards pERK1/2 and IP1 accumulation may explain their suppression of PTH levels in vivo at concentrations that have no effect on serum calcitonin levels. The demonstration that AC-265347 promotes CaS receptor receptor signalling, but not trafficking reveals a novel profile of ligand-biased modulation at CaS receptors The identification of allosteric modulators that bias CaS receptor signalling towards distinct intracellular pathways provides an opportunity to develop desirable biased signalling profiles in vivo for mediating selective physiological responses.
Collapse
Affiliation(s)
- A E Cook
- Drug Discovery Biology and Department of Pharmacology, Monash University, Parkville, Vic., Australia
| | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Fetahu IS, Höbaus J, Aggarwal A, Hummel DM, Tennakoon S, Mesteri I, Baumgartner-Parzer S, Kállay E. Calcium-sensing receptor silencing in colorectal cancer is associated with promoter hypermethylation and loss of acetylation on histone 3. Int J Cancer 2014; 135:2014-23. [PMID: 24691920 PMCID: PMC4282356 DOI: 10.1002/ijc.28856] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 03/06/2014] [Indexed: 12/25/2022]
Abstract
The calcium-sensing receptor (CaSR) is suggested to mediate the antiproliferative effects of calcium in colon. However, in colorectal cancer (CRC) the expression of the CaSR is silenced and the underlying mechanisms leading to its loss are poorly understood. We investigated whether loss of the CaSR expression in colorectal tumors is caused by DNA hypermethylation and imbalance of transcriptionally permissive/repressive histone alterations. We observed significantly lower CaSR mRNA expression (n = 65, p < 0.001) in colorectal tumors compared with the adjacent mucosa from the same patient. Immunofluorescence staining confirmed downregulation of the CaSR protein also. The CaSR promoter was methylated to a greater extent in tumors compared with adjacent mucosa as determined by bisulfite sequencing (n = 20, p < 0.01) and by pyrosequencing (n = 45, p < 0.001), and methylation correlated inversely with mRNA expression (n = 20, ρ = -0.310, p < 0.05 and n = 45, ρ = -0.588, p < 0.001). Treatments with 5-aza-2'-deoxycytidine (DAC), a DNA methyltransferase inhibitor and/or with two different histone deacetylase inhibitors, trichostatin A (TSA) or suberoylanilide hydroxamic acid (SAHA) restored the expression of CaSR in colon cancer cells. Restored CaSR expression in Coga1A and HT29 cells was functional. Inhibition of lysine-specific demethylase 1 (LSD1) to prevent demethylation of mono- and dimethylated H3K4, increased CaSR expression only marginally. Our data show that hypermethylation of the CaSR promoter and H3K9 deacetylation, but not H3K4me2 demethylation are important factors that cause silencing of the CaSR in colorectal cancer.
Collapse
Affiliation(s)
- Irfete S Fetahu
- Department of Pathophysiology and Allergy Research, Medical University of ViennaVienna, Austria
| | - Julia Höbaus
- Department of Pathophysiology and Allergy Research, Medical University of ViennaVienna, Austria
| | - Abhishek Aggarwal
- Department of Pathophysiology and Allergy Research, Medical University of ViennaVienna, Austria
| | - Doris M Hummel
- Department of Pathophysiology and Allergy Research, Medical University of ViennaVienna, Austria
| | - Samawansha Tennakoon
- Department of Pathophysiology and Allergy Research, Medical University of ViennaVienna, Austria
| | - Ildiko Mesteri
- Department of Pathology, Medical University of ViennaVienna, Austria
| | | | - Enikő Kállay
- Department of Pathophysiology and Allergy Research, Medical University of ViennaVienna, Austria
| |
Collapse
|
29
|
Leach K, Sexton PM, Christopoulos A, Conigrave AD. Engendering biased signalling from the calcium-sensing receptor for the pharmacotherapy of diverse disorders. Br J Pharmacol 2014; 171:1142-55. [PMID: 24111791 DOI: 10.1111/bph.12420] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 08/22/2013] [Accepted: 08/26/2013] [Indexed: 12/14/2022] Open
Abstract
The human calcium-sensing receptor (CaSR) is widely expressed in the body, where its activity is regulated by multiple orthosteric and endogenous allosteric ligands. Each ligand stabilizes a unique subset of conformational states, which enables the CaSR to couple to distinct intracellular signalling pathways depending on the extracellular milieu in which it is bathed. Differential signalling arising from distinct receptor conformations favoured by each ligand is referred to as biased signalling. The outcome of CaSR activation also depends on the cell type in which it is expressed. Thus, the same ligand may activate diverse pathways in distinct cell types. Given that the CaSR is implicated in numerous physiological and pathophysiological processes, it is an ideal target for biased ligands that could be rationally designed to selectively regulate desired signalling pathways in preferred cell types.
Collapse
Affiliation(s)
- K Leach
- Pharmaceutical Sciences, Monash University, Melbourne, Vic., Australia
| | | | | | | |
Collapse
|
30
|
Wu Y, Wang J, Zhou H, Yu X, Hu L, Meng F, Jiang S. Effects of calcium signaling on coagulation factor VIIa-induced proliferation and migration of the SW620 colon cancer cell line. Mol Med Rep 2014; 10:3021-6. [PMID: 25323578 DOI: 10.3892/mmr.2014.2665] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 07/21/2014] [Indexed: 11/05/2022] Open
Abstract
Tissue factor (TF)/VIIa/protease‑activated receptor 2 (PAR2) has been shown to trigger the ERK1/2 signaling pathway. This was shown to be closely associated with the proliferation and migration of SW620 colon cancer cells; however, the detailed mechanisms remain unclear. The aim of the present study was to elucidate the effects of calcium signaling on the proliferation and migration of SW620 cells induced by coagulation factor VIIa. The results demonstrated that VIIa and PAR2 agonist PAR2‑AP increased [Ca2+]i in SW620 cells. In addition, VIIa‑and PAR2‑AP‑induced ERK1/2 activation was inhibited by thapsigargin (TG)‑induced depletion of intracellular Ca2+ stores and EGTA‑mediated removal of extracellular Ca2+. It was also identified that VIIa and PAR2‑AP‑induced proliferation and migration of SW620 cells was modulated by EGTA and TG. Taken together, the present results indicate that VIIa triggers calcium signaling in SW620 cells, in a TF‑dependent manner, which is critical for VIIa‑induced ERK1/2 activation in SW620 cells. These results suggested that calcium signaling had a vital role in the proliferation and migration of SW620 cells.
Collapse
Affiliation(s)
- Ying Wu
- Department of Internal Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Jing Wang
- Department of Internal Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Hong Zhou
- Department of Clinical Laboratory and Hematology, School of Medical Science and Laboratory Medicine of Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Xiaoyan Yu
- Department of Internal Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Lichao Hu
- Department of Clinical Laboratory and Hematology, School of Medical Science and Laboratory Medicine of Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Fanlu Meng
- Department of Internal Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| | - Shuanghong Jiang
- Department of Internal Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212013, P.R. China
| |
Collapse
|
31
|
Feng J, Xu X, Li B, Brown E, Farris AB, Sun SY, Yang JJ. Prostate cancer metastatic to bone has higher expression of the calcium-sensing receptor (CaSR) than primary prostate cancer. ACTA ACUST UNITED AC 2014; 1. [PMID: 26065011 DOI: 10.14800/rci.270] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The calcium-sensing receptor (CaSR) is the principal regulator of the secretion of parathyroid hormone and plays key roles in extracellular calcium (Ca2+o) homeostasis. It is also thought to participate in the development of cancer, especially bony metastases of breast and prostate cancer. However, the expression of CaSR has not been systematically analyzed in prostate cancer from patients with or without bony metastases. By comparing human prostate cancer tissue sections in microarrays, we found that the CaSR was expressed in both normal prostate and primary prostate cancer as assessed by immunohistochemistry (IHC). We used two methods to analyze the expression level of CaSR. One was the pathological score read by a pathologist, the other was the positivity% obtained from the Aperio positive pixel count algorithm. Both of the methods gave consistent results. Metastatic prostate cancer tissue obtained from bone had higher CaSR expression than primary prostate cancer (P <0.05). The expression of CaSR in primary prostate cancers of patients with metastases to tissues other than bone was not different from that in primary prostate cancer of patients with or without bony metastases (P >0.05). The expression of CaSR in cancer tissue was not associated with the stage or status of differentiation of the cancer. These results suggest that CaSR may have a role in promoting bony metastasis of prostate cancer, hence raising the possibility of reducing the risk of such metastases with CaSR-based therapeutics.
Collapse
Affiliation(s)
- Jie Feng
- Department of Chemistry, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia 30303
| | - Xiaojun Xu
- Department of Chemistry, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia 30303
| | - Bo Li
- Department of Hematology and Medical Oncology, Emory University School of Medicine and Winship Cancer Institute, Atlanta, GA 30322
| | - Edward Brown
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115
| | - Alton B Farris
- Department of Pathology, Emory University, Atlanta, GA 30322
| | - Shi-Yong Sun
- Department of Hematology and Medical Oncology, Emory University School of Medicine and Winship Cancer Institute, Atlanta, GA 30322
| | - Jenny J Yang
- Department of Chemistry, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia 30303
| |
Collapse
|
32
|
Keum N, Lee DH, Greenwood DC, Zhang X, Giovannucci EL. Calcium intake and colorectal adenoma risk: dose-response meta-analysis of prospective observational studies. Int J Cancer 2014; 136:1680-7. [PMID: 25156950 DOI: 10.1002/ijc.29164] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 08/10/2014] [Accepted: 08/12/2014] [Indexed: 12/14/2022]
Abstract
Evidence from randomized controlled trials suggests that calcium may protect against recurrence of colorectal adenomas, which could lead to the subsequent prevention of cancer. Yet the trials used only a large single dose and were of small sizes, and thus, knowledge of the dose-response relationship and influence on high-risk adenomas is limited. To address these issues, we conducted linear and nonlinear dose-response meta-analyses primarily based on prospective observational studies published up to July 2014 identified from PubMed and Embase. Summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated for total and supplemental calcium intake, respectively, using a random-effects model. For total calcium intake, summary RR for each 300 mg/day increase was 0.95 (95% CI = 0.92-0.98; I(2) = 45%; eight studies with 11,005 cases; range of intake = 333-2,229 mg/day). Evidence of nonlinearity was indicated: approximately, compared to 550 mg/day of total calcium intake, the summary RR was 0.92 (95% CI = 0.89-0.94) at 1,000 mg/day and 0.87 (95% CI = 0.84-0.90) at 1,450 mg/day (pnonlinearity < 0.01). Associations were stronger for high-risk adenomas (≥1 cm in diameter, (tubulo)villous histology, dysplasia, or multiplicity): approximately, compared to 550 mg/day of total calcium intake, the summary RR was 0.77 (95% CI = 0.74-0.81) at 1,000 mg/day and reduced to 0.69 (95% CI = 0.66-0.73) at 1,450 mg/da (pnonlinearity < 0.01). For supplemental calcium intake, summary RR of total adenoma risk for each 300 mg/day increase was 0.96 (95% CI = 0.93-0.99; I(2) = 0%; three studies with 4,548 cases; range of supplementation = 0-1,366 mg/day). In conclusion, calcium intake may continue to decrease the risk of adenomas, particularly high-risk adenomas, over a wide range of calcium intake.
Collapse
Affiliation(s)
- NaNa Keum
- Department of Nutrition, Harvard School of Public Health, Boston, MA; Department of Epidemiology, Harvard School of Public Health, Boston, MA
| | | | | | | | | |
Collapse
|
33
|
Emerging roles of the extracellular calcium-sensing receptor in nutrient sensing: control of taste modulation and intestinal hormone secretion. Br J Nutr 2014; 111 Suppl 1:S16-22. [PMID: 24382107 DOI: 10.1017/s0007114513002250] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The extracellular Ca-sensing receptor (CaSR) is a sensor for a number of key nutrients within the body, including Ca ions (Ca²⁺) and L-amino acids. The CaSR is expressed in a number of specialised cells within the gastrointestinal (GI) tract, and much work has been done to examine CaSR's role as a nutrient sensor in this system. This review article examines two emerging roles for the CaSR within the GI tract--as a mediator of kokumi taste modulation in taste cells and as a regulator of dietary hormone release in response to L-amino acids in the intestine.
Collapse
|
34
|
Meng K, Xu J, Zhang C, Zhang R, Yang H, Liao C, Jiao J. Calcium sensing receptor modulates extracellular calcium entry and proliferation via TRPC3/6 channels in cultured human mesangial cells. PLoS One 2014; 9:e98777. [PMID: 24905090 PMCID: PMC4048219 DOI: 10.1371/journal.pone.0098777] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 05/07/2014] [Indexed: 12/31/2022] Open
Abstract
Calcium-sensing receptor (CaSR) has been demonstrated to be present in several tissues and cells unrelated to systemic calcium homeostasis, where it regulates a series of diverse cellular functions. A previous study indicated that CaSR is expressed in mouse glomerular mesangial cells (MCs), and stimulation of CaSR induces cell proliferation. However, the signaling cascades initiated by CaSR activation in MCs are currently unknown. In this study, our data demonstrate that CaSR mRNA and protein are expressed in a human mesangial cell line. Activating CaSR with high extracellular Ca2+ concentration ([Ca2+]o) or spermine induces a phospholipase C (PLC)-dependent increase in intracellular Ca2+ concentration ([Ca2+]i). Interestingly, the CaSR activation-induced increase in [Ca2+]i results not only from intracellular Ca2+ release from internal stores but also from canonical transient receptor potential (TRPC)-dependent Ca2+ influx. This increase in Ca2+ was attenuated by treatment with a nonselective TRPC channel blocker but not by treatment with a voltage-gated calcium blocker or Na+/Ca2+ exchanger inhibitor. Furthermore, stimulation of CaSR by high [Ca2+]o enhanced the expression of TRPC3 and TRPC6 but not TRPC1 and TRPC4, and siRNA targeting TRPC3 and TRPC6 attenuated the CaSR activation-induced [Ca2+]i increase. Further experiments indicate that 1-oleoyl-2-acetyl-sn-glycerol (OAG), a known activator of receptor-operated calcium channels, significantly enhances the CaSR activation-induced [Ca2+]i increase. Moreover, under conditions in which intracellular stores were already depleted with thapsigargin (TG), CaSR agonists also induced an increase in [Ca2+]i, suggesting that calcium influx stimulated by CaSR agonists does not require the release of calcium stores. Finally, our data indicate that pharmacological inhibition and knock down of TRPC3 and TRPC6 attenuates the CaSR activation-induced cell proliferation in human MCs. With these data, we conclude that CaSR activation mediates Ca2+ influx and cell proliferation via TRPC3 and TRPC6 in human MCs.
Collapse
Affiliation(s)
- Kexin Meng
- Department of Nephrology, The Second Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Jia Xu
- Department of Nephrology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Chengwei Zhang
- Department of Nephrology, The Second Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Rui Zhang
- Department of Nephrology, The Second Affiliated Hospital, Harbin Medical University, Harbin, China
| | - He Yang
- Department of Nephrology, The Second Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Chang Liao
- Department of Nephrology, The Second Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Jundong Jiao
- Department of Nephrology, The Second Affiliated Hospital, Harbin Medical University, Harbin, China
- Institute of Nephrology, Harbin Medical University, Harbin, China
- * E-mail:
| |
Collapse
|
35
|
McCormick K, Baillie GS. Compartmentalisation of second messenger signalling pathways. Curr Opin Genet Dev 2014; 27:20-5. [PMID: 24791689 DOI: 10.1016/j.gde.2014.02.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 02/21/2014] [Accepted: 02/22/2014] [Indexed: 01/21/2023]
Abstract
The ability of a cell to transform an extracellular stimulus into a downstream event that directs specific physiological outcomes, requires the orchestrated, spatial and temporal response of many signalling proteins. The notion of compartmentalised signalling pathways was popularised in the 1980s by Brunton and colleagues, with their discovery that spatially segregated cAMP directs a variety of signalling responses in cardiomyocytes. It is now understood that compartmentalisation is a common mechanism used by all cells to ensure the interaction of signalling 'second messenger' molecules with localised 'pools' of appropriate effector proteins. In this way, the cell can elicit differential cellular responses by using a single, freely diffusible, molecular species. Recently, the compartmentalisation schemes employed by signalling systems involving cyclic nucleotides, calcium and nitric oxide have been elucidated and as a result, the varied range of functional consequences underpinned by such strategies can be better appreciated.
Collapse
Affiliation(s)
- Kristie McCormick
- Institute of Cardiovascular and Medical Sciences, CMVLS, Wolfson-Link Building, University of Glasgow, Glasgow G12 8QQ, UK
| | - George S Baillie
- Institute of Cardiovascular and Medical Sciences, CMVLS, Wolfson-Link Building, University of Glasgow, Glasgow G12 8QQ, UK.
| |
Collapse
|
36
|
Webb SE, Miller AL. Calcium signaling in extraembryonic domains during early teleost development. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 304:369-418. [PMID: 23809440 DOI: 10.1016/b978-0-12-407696-9.00007-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
It is becoming recognized that the extraembryonic domains of developing vertebrates, that is, those that make no cellular contribution to the embryo proper, act as important signaling centers that induce and pattern the germ layers and help establish the key embryonic axes. In the embryos of teleost fish, in particular, significant progress has been made in understanding how signaling activity in extraembryonic domains, such as the enveloping layer, the yolk syncytial layer, and the yolk cell, might help regulate development via a combination of inductive interactions, cellular dynamics, and localized gene expression. Ca(2+) signaling in a variety of forms that include propagating waves and standing gradients is a feature found in all three teleostean extraembryonic domains. This leads us to propose that in addition to their other well-characterized signaling activities, extraembryonic domains are well suited (due to their relative stability and continuity) to act as Ca(2+) signaling centers and conduits.
Collapse
Affiliation(s)
- Sarah E Webb
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | | |
Collapse
|
37
|
Basso D, Bozzato D, Padoan A, Moz S, Zambon CF, Fogar P, Greco E, Scorzeto M, Simonato F, Navaglia F, Fassan M, Pelloso M, Dupont S, Pedrazzoli S, Fassina A, Plebani M. Inflammation and pancreatic cancer: molecular and functional interactions between S100A8, S100A9, NT-S100A8 and TGFβ1. Cell Commun Signal 2014; 12:20. [PMID: 24670043 PMCID: PMC4108065 DOI: 10.1186/1478-811x-12-20] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 03/08/2014] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND In order to gain further insight on the crosstalk between pancreatic cancer (PDAC) and stromal cells, we investigated interactions occurring between TGFβ1 and the inflammatory proteins S100A8, S100A9 and NT-S100A8, a PDAC-associated S100A8 derived peptide, in cell signaling, intracellular calcium (Cai2+) and epithelial to mesenchymal transition (EMT). NF-κB, Akt and mTOR pathways, Cai2+ and EMT were studied in well (Capan1 and BxPC3) and poorly differentiated (Panc1 and MiaPaCa2) cell lines. RESULTS NT-S100A8, one of the low molecular weight N-terminal peptides from S100A8 to be released by PDAC-derived proteases, shared many effects on NF-κB, Akt and mTOR signaling with S100A8, but mainly with TGFβ1. The chief effects of S100A8, S100A9 and NT-S100A8 were to inhibit NF-κB and stimulate mTOR; the molecules inhibited Akt in Smad4-expressing, while stimulated Akt in Smad4 negative cells. By restoring Smad4 expression in BxPC3 and silencing it in MiaPaCa2, S100A8 and NT-S100A8 were shown to inhibit NF-κB and Akt in the presence of an intact TGFβ1 canonical signaling pathway. TGFβ1 counteracted S100A8, S100A9 and NT-S100A8 effects in Smad4 expressing, not in Smad4 negative cells, while it synergized with NT-S100A8 in altering Cai2+ and stimulating PDAC cell growth. The effects of TGFβ1 on both EMT (increased Twist and decreased N-Cadherin expression) and Cai2+ were antagonized by S100A9, which formed heterodimers with TGFβ1 (MALDI-TOF/MS and co-immuno-precipitation). CONCLUSIONS The effects of S100A8 and S100A9 on PDAC cell signaling appear to be cell-type and context dependent. NT-S100A8 mimics the effects of TGFβ1 on cell signaling, and the formation of complexes between TGFβ1 with S100A9 appears to be the molecular mechanism underlying the reciprocal antagonism of these molecules on cell signaling, Cai2+ and EMT.
Collapse
Affiliation(s)
- Daniela Basso
- Department of Laboratory Medicine, University-Hospital of Padova, Via Giustiniani 2, 35128 Padova, Italy.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Young SH, Rey O, Sinnett-Smith J, Rozengurt E. Intracellular Ca2+ oscillations generated via the Ca2+-sensing receptor are mediated by negative feedback by PKCα at Thr888. Am J Physiol Cell Physiol 2013; 306:C298-306. [PMID: 24336654 DOI: 10.1152/ajpcell.00194.2013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
To clarify the mechanism(s) underlying intracellular Ca(2+) concentration ([Ca(2+)]i) oscillations induced by an elevation in extracellular Ca(2+) concentration ([Ca(2+)]e) via the extracellular Ca(2+)-sensing receptor (CaR), we analyzed the pattern of [Ca(2+)]i response in multiple (2,303) individual HEK-293 cells transfected with the human CaR. An increase in the [Ca(2+)]e from 1.5 to 3 mM produced oscillatory fluctuations in [Ca(2+)]i in 70% of the cell population. To determine the role of PKC in the generation of [Ca(2+)]i oscillations, cells were exposed to increasing concentrations (0.5-5 μM) of the preferential PKC inhibitor Ro-31-8220 before stimulation by extracellular Ca(2+). Ro-31-8220 at 3-5 μM completely eliminated the [Ca(2+)]e-evoked [Ca(2+)]i oscillations and transformed the pattern to a peak and sustained plateau response. Treatment with other broad PKC inhibitors, including GFI or Gö6983, produced an identical response. Similarly, treatment with Ro-31-8220 or GFI eliminated [Ca(2+)]e-evoked [Ca(2+)]i oscillations in colon-derived SW-480 cells expressing the CaR. Treatment with inhibitors targeting classic PKCs, including Gö6976 and Ro-32-0432 as well as small interfering RNA-mediated knockdown of PKCα, strikingly reduced the proportion of cell displaying [Ca(2+)]e-evoked [Ca(2+)]i oscillations. Furthermore, none of the cells analyzed expressing a CaR mutant in which the major PKC phosphorylation site Thr(888) was converted to alanine (CaRT888A) showed [Ca(2+)]i oscillations after CaR activation. Our results show that [Ca(2+)]i oscillations induced by activation of the CaR in response to an increase in extracellular Ca(2+) or exposure to the calcimimetic R-568 result from negative feedback involving PKCα-mediated phosphorylation of the CaR at Thr(888).
Collapse
Affiliation(s)
- Steven H Young
- Division of Digestive Diseases, Department of Medicine, Center for Ulcer Research and Education: Digestive Diseases Research Center David Geffen School of Medicine and Molecular Biology Institute, University of California, Los Angeles, California; and
| | | | | | | |
Collapse
|
39
|
Borowiec AS, Bidaux G, Pigat N, Goffin V, Bernichtein S, Capiod T. Calcium channels, external calcium concentration and cell proliferation. Eur J Pharmacol 2013; 739:19-25. [PMID: 24291106 DOI: 10.1016/j.ejphar.2013.10.072] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 09/28/2013] [Accepted: 10/17/2013] [Indexed: 11/16/2022]
Abstract
Evidence for a role for calcium channel proteins in cell proliferation is numerous suggesting that calcium influx is essential in this physiological process. Several studies in the past thirty years have demonstrated that calcium channel expression levels are determinant in cell proliferation. Voltage-gated, store-operated, second messengers and receptor-operated calcium channels have been associated to cell proliferation. However, the relationship between calcium influx and cell proliferation can be uncoupled in transformed and cancer cells, resulting in an external calcium-independent proliferation. Thus, protein expression could be more important than channel function to trigger cell proliferation suggesting that additional channel functions may be responsible to reconcile calcium channel expression and cell proliferation. When needed, external calcium concentration is obviously important for calcium channel function but it also regulates calcium sensing receptor (CaSR) activity. CaSR can up- or down-regulate cell proliferation depending on physiological conditions. CaSR sensitivity to external calcium is within the 0.5 to 5 mM range and therefore, the role of these receptors in cell proliferation must be taken into account. We therefore suggest here that cell proliferation rates could depend on the relative balance between calcium influx and CaSR activation.
Collapse
Affiliation(s)
| | - Gabriel Bidaux
- INSERM U1003, LabEx ICST, Université Lille 1, Villeneuve d'Ascq F-59655, France
| | - Natascha Pigat
- INSERM U845, Research Center Growth and Signalling Research Center, Paris Descartes University, Sorbonne Paris Cité, Faculty of Medicine, Bâtiment Leriche, 96 rue Didot, Paris F-75993, France
| | - Vincent Goffin
- INSERM U845, Research Center Growth and Signalling Research Center, Paris Descartes University, Sorbonne Paris Cité, Faculty of Medicine, Bâtiment Leriche, 96 rue Didot, Paris F-75993, France
| | - Sophie Bernichtein
- INSERM U845, Research Center Growth and Signalling Research Center, Paris Descartes University, Sorbonne Paris Cité, Faculty of Medicine, Bâtiment Leriche, 96 rue Didot, Paris F-75993, France
| | - Thierry Capiod
- INSERM U845, Research Center Growth and Signalling Research Center, Paris Descartes University, Sorbonne Paris Cité, Faculty of Medicine, Bâtiment Leriche, 96 rue Didot, Paris F-75993, France.
| |
Collapse
|
40
|
Riccardi D, Brennan SC, Chang W. The extracellular calcium-sensing receptor, CaSR, in fetal development. Best Pract Res Clin Endocrinol Metab 2013; 27:443-53. [PMID: 23856271 PMCID: PMC4462341 DOI: 10.1016/j.beem.2013.02.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In fetal mammals, serum levels of both total and ionized calcium significantly exceed those in the adult. This relative fetal hypercalcemia is crucial for skeletal development and is maintained irrespectively of maternal serum calcium levels. Elegant studies by Kovacs and Kronenberg have previously addressed the role of the CaSR in creating and maintaining this relative fetal hypercalcemia, through the regulation of parathyroid hormone-related peptide secretion. More recently we have shown that the CaSR is widely distributed throughout the developing fetus, where the receptor plays major, unexpected roles in ensuring growth and maturation of several organs. In this article, we present evidence for a role of the CaSR in the control of skeletal development, and how fetal hypercalcemia, acting through the CaSR, regulates lung development.
Collapse
Affiliation(s)
- Daniela Riccardi
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Sarah C Brennan
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Wenhan Chang
- University of California San Francisco, California, USA
| |
Collapse
|
41
|
Investigation of tumor suppressing function of CACNA2D3 in esophageal squamous cell carcinoma. PLoS One 2013; 8:e60027. [PMID: 23560067 PMCID: PMC3616168 DOI: 10.1371/journal.pone.0060027] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 02/22/2013] [Indexed: 12/21/2022] Open
Abstract
Background Deletion of 3p is one of the most frequent genetic alterations in esophageal squamous cell carcinoma (ESCC), suggesting the existence of one or more tumor suppressor genes (TSGs) within these regions. In this study, one TSG, CACNA2D3 at 3p21.1, was characterized. Methods Expression of CACNA2D3 in ESCCs was tested by quantitative real-time PCR and tissue microarray. The mechanism of CACNA2D3 downregulation was investigated by methylation-specific polymerase chain reaction (MS-PCR). The tumor suppressive function of CACNA2D3 was characterized by both in vitro and in vivo tumorigenic assays, cell migration and invasion assays. Results CACNA2D3 was frequently downregulated in ESCCs (24/48, 50%), which was significantly associated with promoter methylation and allele loss (P<0.05). Tissue microarray result showed that downregulation of CACNA2D3 was detected in (127/224, 56.7%) ESCCs, which was significantly associated with lymph node metastasis (P = 0.01), TNM staging (P = 0.003) and poor outcome of ESCC patients (P<0.05). Functional studies demonstrated that CACNA2D3 could inhibit tumorigenicity, cell motility and induce apoptosis. Mechanism study found that CACNA2D3 could arrest cell cycle at G1/S checkpoint by increasing expressions of p21 and p53 and decreasing expression of CDK2. In addition, CACNA2D3 could upregulate intracellular free cytosolic Ca2+ and subsequently induce apoptosis. Conclusion CACNA2D3 is a novel TSG responsible to the 3p21 deletion event and plays a critical suppressing role in the development and progression of ESCC.
Collapse
|
42
|
Calcium sensing receptor signalling in physiology and cancer. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1833:1732-44. [PMID: 23267858 DOI: 10.1016/j.bbamcr.2012.12.011] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 12/10/2012] [Accepted: 12/12/2012] [Indexed: 12/13/2022]
Abstract
The calcium sensing receptor (CaSR) is a class C G-protein-coupled receptor that is crucial for the feedback regulation of extracellular free ionised calcium homeostasis. While extracellular calcium (Ca(2+)o) is considered the primary physiological ligand, the CaSR is activated physiologically by a plethora of molecules including polyamines and l-amino acids. Activation of the CaSR by different ligands has the ability to stabilise unique conformations of the receptor, which may lead to preferential coupling of different G proteins; a phenomenon termed 'ligand-biased signalling'. While mutations of the CaSR are currently not linked with any malignancies, altered CaSR expression and function are associated with cancer progression. Interestingly, the CaSR appears to act both as a tumour suppressor and an oncogene, depending on the pathophysiology involved. Reduced expression of the CaSR occurs in both parathyroid and colon cancers, leading to loss of the growth suppressing effect of high Ca(2+)o. On the other hand, activation of the CaSR might facilitate metastasis to bone in breast and prostate cancer. A deeper understanding of the mechanisms driving CaSR signalling in different tissues, aided by a systems biology approach, will be instrumental in developing novel drugs that target the CaSR or its ligands in cancer. This article is part of a Special Issue entitled: 12th European Symposium on Calcium.
Collapse
|
43
|
Epigenetic Methylation of Parathyroid CaR and VDR Promoters in Experimental Secondary Hyperparathyroidism. Int J Nephrol 2012; 2012:123576. [PMID: 23094155 PMCID: PMC3474253 DOI: 10.1155/2012/123576] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 09/04/2012] [Indexed: 11/25/2022] Open
Abstract
Secondary hyperparathyroidism (s-HPT) in uremia is characterized by decreased expression in the parathyroids of calcium sensing (CaR) and vitamin D receptors (VDR). Parathyroid hormone (PTH) is normalized despite low levels of CaR and VDR after experimental reversal of uremia. The expression of CaR in parathyroid cultures decreases rapidly. Methylation of promoter regions is often detected during epigenetic downregulation of gene expression. Therefore, using an experimental rat model, we examined changes in methylation levels of parathyroid CaR and VDR promoters in vivo and in vitro. Methods. Uremia was induced by 5/6 nephrectomy. Melting temperature profiling of CaR and VDR PCR products after bisulfite treatment of genomic DNA from rat parathyroids was performed. Real-time PCR measured expression of PTH, CaR, VDR, and klotho genes in vitro. Results. Parathyroids from uremic rats had similar low levels of methylation in vivo and in vitro. In culture, a significant downregulation of CaR, VDR, and klotho within two hours of incubation was observed, while housekeeping genes remained stable for 24 hours. Conclusion. In uremic s-HPT and in vitro, no overall changes in methylation levels in the promoter regions of parathyroid CaR and VDR genes were found. Thus, epigenetic methylation of these promoters does not explain decreased parathyroid expression of CaR and VDR genes in uremic s-HPT.
Collapse
|
44
|
Bandyopadhyay BC, Swaim WD, Sarkar A, Liu X, Ambudkar IS. Extracellular Ca(2+) sensing in salivary ductal cells. J Biol Chem 2012; 287:30305-30316. [PMID: 22778254 DOI: 10.1074/jbc.m112.394122jbc.m112.39412274] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023] Open
Abstract
Ca(2+) is secreted from the salivary acinar cells as an ionic constituent of primary saliva. Ions such as Na(+) and Cl(-) get reabsorbed whereas primary saliva flows through the salivary ductal system. Although earlier studies have shown that salivary [Ca(2+)] decreases as it flows down the ductal tree into the oral cavity, ductal reabsorption of Ca(2+) remains enigmatic. Here we report a potential role for the G protein-coupled receptor, calcium-sensing receptor (CSR), in the regulation of Ca(2+) reabsorption by salivary gland ducts. Our data show that CSR is present in the apical region of ductal cells where it is co-localized with transient receptor potential canonical 3 (TRPC3). CSR is activated in isolated salivary gland ducts as well as a ductal cell line (SMIE) by altering extracellular [Ca(2+)] or by aromatic amino acid, L-phenylalanine (L-Phe, endogenous component of saliva), as well as neomycin. CSR activation leads to Ca(2+) influx that, in polarized cells grown on a filter support, is initiated in the luminal region. We show that TRPC3 contributes to Ca(2+) entry triggered by CSR activation. Further, stimulation of CSR in SMIE cells enhances the CSR-TRPC3 association as well as surface expression of TRPC3. Together our findings suggest that CSR could serve as a Ca(2+) sensor in the luminal membrane of salivary gland ducts and regulate reabsorption of [Ca(2+)] from the saliva via TRPC3, thus contributing to maintenance of salivary [Ca(2+)]. CSR could therefore be a potentially important protective mechanism against formation of salivary gland stones (sialolithiasis) and infection (sialoadenitis).
Collapse
Affiliation(s)
- Bidhan C Bandyopadhyay
- Calcium Signaling Laboratory, Research Service, Veterans Affairs Medical Center, Washington, DC 20422, USA.
| | | | | | | | | |
Collapse
|
45
|
Bandyopadhyay BC, Swaim WD, Sarkar A, Liu X, Ambudkar IS. Extracellular Ca(2+) sensing in salivary ductal cells. J Biol Chem 2012; 287:30305-16. [PMID: 22778254 DOI: 10.1074/jbc.m112.394122] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ca(2+) is secreted from the salivary acinar cells as an ionic constituent of primary saliva. Ions such as Na(+) and Cl(-) get reabsorbed whereas primary saliva flows through the salivary ductal system. Although earlier studies have shown that salivary [Ca(2+)] decreases as it flows down the ductal tree into the oral cavity, ductal reabsorption of Ca(2+) remains enigmatic. Here we report a potential role for the G protein-coupled receptor, calcium-sensing receptor (CSR), in the regulation of Ca(2+) reabsorption by salivary gland ducts. Our data show that CSR is present in the apical region of ductal cells where it is co-localized with transient receptor potential canonical 3 (TRPC3). CSR is activated in isolated salivary gland ducts as well as a ductal cell line (SMIE) by altering extracellular [Ca(2+)] or by aromatic amino acid, L-phenylalanine (L-Phe, endogenous component of saliva), as well as neomycin. CSR activation leads to Ca(2+) influx that, in polarized cells grown on a filter support, is initiated in the luminal region. We show that TRPC3 contributes to Ca(2+) entry triggered by CSR activation. Further, stimulation of CSR in SMIE cells enhances the CSR-TRPC3 association as well as surface expression of TRPC3. Together our findings suggest that CSR could serve as a Ca(2+) sensor in the luminal membrane of salivary gland ducts and regulate reabsorption of [Ca(2+)] from the saliva via TRPC3, thus contributing to maintenance of salivary [Ca(2+)]. CSR could therefore be a potentially important protective mechanism against formation of salivary gland stones (sialolithiasis) and infection (sialoadenitis).
Collapse
Affiliation(s)
- Bidhan C Bandyopadhyay
- Calcium Signaling Laboratory, Research Service, Veterans Affairs Medical Center, Washington, DC 20422, USA.
| | | | | | | | | |
Collapse
|
46
|
Breitwieser GE. Minireview: the intimate link between calcium sensing receptor trafficking and signaling: implications for disorders of calcium homeostasis. Mol Endocrinol 2012; 26:1482-95. [PMID: 22745192 DOI: 10.1210/me.2011-1370] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The calcium-sensing receptor (CaSR) regulates organismal Ca(2+) homeostasis. Dysregulation of CaSR expression or mutations in the CASR gene cause disorders of Ca(2+) homeostasis and contribute to the progression or severity of cancers and cardiovascular disease. This brief review highlights recent findings that define the CaSR life cycle, which controls the cellular abundance of CaSR and CaSR signaling. A novel mechanism, termed agonist-driven insertional signaling (ADIS), contributes to the unique hallmarks of CaSR signaling, including the high degree of cooperativity and the lack of functional desensitization. Agonist-mediated activation of plasma membrane-localized CaSR increases the rate of insertion of CaSR at the plasma membrane without altering the constitutive endocytosis rate, thereby acutely increasing the maximum signaling response. Prolonged CaSR signaling requires a large intracellular ADIS-mobilizable pool of CaSR, which is maintained by signaling-mediated increases in biosynthesis. This model provides a rational framework for characterizing the defects caused by CaSR mutations and the altered functional expression of wild-type CaSR in disease states. Mechanistic dissection of ADIS of CaSR should lead to optimized pharmacological approaches to normalize CaSR signaling in disorders of Ca(2+) homeostasis.
Collapse
Affiliation(s)
- Gerda E Breitwieser
- Weis Center for Research, Geisinger Clinic, Danville, Pennsylvania 17822-2604, USA.
| |
Collapse
|
47
|
Battula VL, Shi Y, Evans KW, Wang RY, Spaeth EL, Jacamo RO, Guerra R, Sahin AA, Marini FC, Hortobagyi G, Mani SA, Andreeff M. Ganglioside GD2 identifies breast cancer stem cells and promotes tumorigenesis. J Clin Invest 2012; 122:2066-78. [PMID: 22585577 DOI: 10.1172/jci59735] [Citation(s) in RCA: 200] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 03/28/2012] [Indexed: 01/06/2023] Open
Abstract
Cancer stem cells (CSCs) are a small subpopulation of cancer cells that have increased resistance to conventional therapies and are capable of establishing metastasis. However, only a few biomarkers of CSCs have been identified. Here, we report that ganglioside GD2 (a glycosphingolipid) identifies a small fraction of cells in human breast cancer cell lines and patient samples that are capable of forming mammospheres and initiating tumors with as few as 10 GD2+ cells. In addition, the majority of GD2+ cells are also CD44hiCD24lo, the previously established CSC-associated cell surface phenotype. Gene expression analysis revealed that GD3 synthase (GD3S) is highly expressed in GD2+ as well as in CD44hiCD24lo cells and that interference with GD3S expression, either by shRNA or using a pharmacological inhibitor, reduced the CSC population and CSC-associated properties. GD3S knockdown completely abrogated tumor formation in vivo. Also, induction of epithelial-mesenchymal transition (EMT) in transformed human mammary epithelial cells (HMLER cells) dramatically increased GD2 as well as GD3S expression in these cells, suggesting a role of EMT in the origin of GD2+ breast CSCs. In summary, we identified GD2 as a new CSC-specific cell surface marker and GD3S as a potential therapeutic target for CSCs, with the possibility of improving survival and cure rates in patients with breast cancer.
Collapse
Affiliation(s)
- Venkata Lokesh Battula
- Section of Molecular Hematology and Therapy, Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
The role of the calcium-sensing receptor in human disease. Clin Biochem 2012; 45:943-53. [PMID: 22503956 DOI: 10.1016/j.clinbiochem.2012.03.034] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 03/22/2012] [Accepted: 03/27/2012] [Indexed: 01/18/2023]
Abstract
Following the discovery of the calcium-sensing receptor (CaSR) in 1993, its pivotal role in disorders of calcium homeostasis such as Familial Hypocalciuric Hypercalcemia (FHH) was quickly demonstrated. Since then, it has become clear that the CaSR has immense functional versatility largely through its ability to activate many different signaling pathways in a ligand- and tissue-specific manner. This allows the receptor to play diverse and crucial roles in human physiology and pathophysiology, both in calcium homeostasis and in tissues and biological processes unrelated to calcium balance. This review covers current knowledge of the role of the CaSR in disorders of calcium homeostasis (FHH, neonatal severe hyperparathyroidism, autosomal dominant hypocalcemia, primary and secondary hyperparathyroidism, hypercalcemia of malignancy) as well as unrelated diseases such as breast and colorectal cancer (where the receptor appears to play a tumor suppressor role), Alzheimer's disease, pancreatitis, diabetes mellitus, hypertension and bone and gastrointestinal disorders. In addition, it examines the use or potential use of CaSR agonists or antagonists (calcimimetics and calcilytics) and other drugs mediated through the CaSR, in the management of disorders as diverse as hyperparathyroidism, osteoporosis and gastrointestinal disease.
Collapse
|
49
|
Oki K, Plonczynski MW, Luis Lam M, Gomez-Sanchez EP, Gomez-Sanchez CE. Potassium channel mutant KCNJ5 T158A expression in HAC-15 cells increases aldosterone synthesis. Endocrinology 2012; 153:1774-82. [PMID: 22315453 PMCID: PMC3320257 DOI: 10.1210/en.2011-1733] [Citation(s) in RCA: 138] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Accepted: 01/09/2012] [Indexed: 11/19/2022]
Abstract
Primary aldosteronism is the most common cause of secondary hypertension, most frequently due to an aldosterone-producing adenoma or idiopathic hyperaldosteronism. Somatic mutations of the potassium channel KCNJ5 in the region of the selectivity filter have been found in a significant number of aldosterone-producing adenomas. There are also familial forms of primary aldosteronism, one of which, familial hyperaldosteronism type 3 which to date has been found in one family who presented with a severe abnormality in aldosterone and 18-oxocortisol production and hypertrophy and hyperplasia of the transitional zone of the adrenal cortex. In familial hyperaldosteronism type 3, there is a genomic mutation causing a T158A change of amino acids within the selectivity filter region of the KCNJ5 gene. We are reporting our studies demonstrating that lentiviral-mediated expression of a gene carrying the T158A mutation of the KCNJ5 in the HAC15 adrenal cortical carcinoma cell line causes a 5.3-fold increase in aldosterone secretion in unstimulated HAC15-KCNJ5 cells and that forskolin-stimulated aldosterone secretion was greater than that of angiotensin II. Expression of the mutated KCNJ5 gene decreases plasma membrane polarization, allowing sodium and calcium influx into the cells. The calcium channel antagonist nifedipine and the calmodulin inhibitor W-7 variably inhibited the effect. Overexpression of the mutated KCNJ5 channel resulted in a modest decrease in HAC15 cell proliferation. These studies demonstrate that the T158A mutation of the KCNJ5 gene produces a marked stimulation in aldosterone biosynthesis that is dependent on membrane depolarization and sodium and calcium influx into the HAC15 adrenal cortical carcinoma cells.
Collapse
Affiliation(s)
- Kenji Oki
- Research and Medical Service, G.V.-Sonny Montgomery Veterans Affairs Medical Center, Jackson, Mississippi 39216, USA
| | | | | | | | | |
Collapse
|
50
|
Abstract
Ingestion of a meal triggers a range of physiological responses both within and outside the gut, and results in the remote modulation of appetite and glucose homeostasis. Luminal contents are sensed by specialised chemosensitive cells scattered throughout the intestinal epithelium. These enteroendocrine and tuft cells make direct contact with the gut lumen and release a range of chemical mediators, which can either act in a paracrine fashion interacting with neighbouring cells and nerve endings or as classical circulating hormones. At the molecular level, the chemosensory machinery involves multiple and complex signalling pathways including activation of G-protein-coupled receptors and solute carrier transporters. This chapter will discuss our current knowledge of the molecular mechanisms underlying intestinal chemosensation with a particular focus on the relatively well-characterised nutrient-triggered secretion from the enteroendocrine system.
Collapse
Affiliation(s)
- Gwen Tolhurst
- Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0XY, UK
| | | | | |
Collapse
|