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Raposo-Garcia S, Cao A, Costas C, Louzao MC, Vilariño N, Vale C, Botana LM. Mouse N2a Neuroblastoma Assay: Uncertainties and Comparison with Alternative Cell-Based Assays for Ciguatoxin Detection. Mar Drugs 2023; 21:590. [PMID: 37999414 PMCID: PMC10672529 DOI: 10.3390/md21110590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 10/25/2023] [Accepted: 11/10/2023] [Indexed: 11/25/2023] Open
Abstract
The growing concern about ciguatera fish poisoning (CF) due to the expansion of the microorganisms producing ciguatoxins (CTXs) increased the need to develop a reliable and fast method for ciguatoxin detection to guarantee food safety. Cytotoxicity assay on the N2a cells sensitized with ouabain (O) and veratridine (V) is routinely used in ciguatoxin detection; however, this method has not been standardized yet. This study demonstrated the low availability of sodium channels in the N2a cells, the great O/V damage to the cells and the cell detachment when the cell viability is evaluated by the classical cytotoxicity assay and confirmed the absence of toxic effects caused by CTXs alone when using the methods that do not require medium removal such as lactate dehydrogenase (LDH) and Alamar blue assays. Different cell lines were evaluated as alternatives, such as human neuroblastoma, which was not suitable for the CTX detection due to the greater sensitivity to O/V and low availability of sodium channels. However, the HEK293 Nav cell line expressing the α1.6 subunit of sodium channels was sensitive to the ciguatoxin without the sensitization with O/V due to its expression of sodium channels. In the case of sensitizing the cells with O/V, it was possible to detect the presence of the ciguatoxin by the classical cytotoxicity MTT method at concentrations as low as 0.0001 nM CTX3C, providing an alternative cell line for the detection of compounds that act on the sodium channels.
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Affiliation(s)
| | | | | | | | | | - Carmen Vale
- Departamento de Farmacología, Facultad de Veterinaria, Universidade de Santiago de Compostela, 27002 Lugo, Spain; (S.R.-G.); (A.C.); (C.C.); (M.C.L.); (N.V.)
| | - Luis M. Botana
- Departamento de Farmacología, Facultad de Veterinaria, Universidade de Santiago de Compostela, 27002 Lugo, Spain; (S.R.-G.); (A.C.); (C.C.); (M.C.L.); (N.V.)
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Martínez-Rendón J, Hinojosa L, Xoconostle-Cázares B, Ramírez-Pool JA, Castillo A, Cereijido M, Ponce A. Ouabain Induces Transcript Changes and Activation of RhoA/ROCK Signaling in Cultured Epithelial Cells (MDCK). Curr Issues Mol Biol 2023; 45:7538-7556. [PMID: 37754259 PMCID: PMC10528288 DOI: 10.3390/cimb45090475] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/30/2023] [Accepted: 09/09/2023] [Indexed: 09/28/2023] Open
Abstract
Ouabain, an organic compound with the ability to strengthen the contraction of the heart muscle, was originally derived from plants. It has been observed that certain mammalian species, including humans, naturally produce ouabain, leading to its classification as a new type of hormone. When ouabain binds to Na+/K+-ATPase, it elicits various physiological effects, although these effects are not well characterized. Previous studies have demonstrated that ouabain, within the concentration range found naturally in the body (10 nmol/L), affects the polarity of epithelial cells and their intercellular contacts, such as tight junctions, adherens junctions, and gap junctional communication. This is achieved by activating signaling pathways involving cSrc and Erk1/2. To further investigate the effects of ouabain within the hormonally relevant concentration range (10 nmol/L), mRNA-seq, a high-throughput sequencing technique, was employed to identify differentially expressed transcripts. The discovery that the transcript encoding MYO9A was among the genes affected prompted an exploration of whether RhoA and its downstream effector ROCK were involved in the signaling pathways through which ouabain influences cell-to-cell contacts in epithelial cells. Supporting this hypothesis, this study reveals the following: (1) Ouabain increases the activation of RhoA. (2) Treatment with inhibitors of RhoA activation (Y27) and ROCK (C3) eliminates the enhancing effect of ouabain on the tight junction seal and intercellular communication via gap junctions. These findings further support the notion that ouabain acts as a hormone to emphasize the epithelial phenotype.
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Affiliation(s)
- Jacqueline Martínez-Rendón
- Department of Physiology, Biophysics and Neurosciences, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de Mexico 07360, Mexico; (J.M.-R.); (L.H.); (A.C.); (M.C.)
- Molecular Medicine Laboratory, Unidad Académica de Medicina Humana y C.S., Campus UAZ Siglo XXI-L1, Universidad Autónoma de Zacatecas, Zacatecas 98160, Mexico
| | - Lorena Hinojosa
- Department of Physiology, Biophysics and Neurosciences, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de Mexico 07360, Mexico; (J.M.-R.); (L.H.); (A.C.); (M.C.)
| | - Beatriz Xoconostle-Cázares
- Department of Biotechnology and Bioengineering, CINVESTAV-IPN, Ciudad de Mexico 07360, Mexico; (B.X.-C.); (J.A.R.-P.)
| | - José Abrahán Ramírez-Pool
- Department of Biotechnology and Bioengineering, CINVESTAV-IPN, Ciudad de Mexico 07360, Mexico; (B.X.-C.); (J.A.R.-P.)
| | - Aída Castillo
- Department of Physiology, Biophysics and Neurosciences, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de Mexico 07360, Mexico; (J.M.-R.); (L.H.); (A.C.); (M.C.)
| | - Marcelino Cereijido
- Department of Physiology, Biophysics and Neurosciences, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de Mexico 07360, Mexico; (J.M.-R.); (L.H.); (A.C.); (M.C.)
| | - Arturo Ponce
- Department of Physiology, Biophysics and Neurosciences, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de Mexico 07360, Mexico; (J.M.-R.); (L.H.); (A.C.); (M.C.)
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Cadart C, Bartz J, Oaks G, Liu MZ, Heald R. Polyploidy in Xenopus lowers metabolic rate by decreasing total cell surface area. Curr Biol 2023; 33:1744-1752.e7. [PMID: 37080197 PMCID: PMC10184464 DOI: 10.1016/j.cub.2023.03.071] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/22/2023] [Accepted: 03/24/2023] [Indexed: 04/22/2023]
Abstract
Although polyploidization is frequent in development, cancer, and evolution, impacts on animal metabolism are poorly understood. In Xenopus frogs, the number of genome copies (ploidy) varies across species and can be manipulated within a species. Here, we show that triploid tadpoles contain fewer, larger cells than diploids and consume oxygen at a lower rate. Drug treatments revealed that the major processes accounting for tadpole energy expenditure include cell proliferation, biosynthesis, and maintenance of plasma membrane potential. While inhibiting cell proliferation did not abolish the oxygen consumption difference between diploids and triploids, treatments that altered cellular biosynthesis or electrical potential did. Combining these results with a simple mathematical framework, we propose that the decrease in total cell surface area lowered production and activity of plasma membrane components including the Na+/K+ ATPase, reducing energy consumption in triploids. Comparison of Xenopus species that evolved through polyploidization revealed that metabolic differences emerged during development when cell size scaled with genome size. Thus, ploidy affects metabolism by altering the cell surface area to volume ratio in a multicellular organism.
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Affiliation(s)
- Clotilde Cadart
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720-3200, USA.
| | - Julianne Bartz
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720-3200, USA
| | - Gillian Oaks
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720-3200, USA
| | - Martin Ziyuan Liu
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720-3200, USA
| | - Rebecca Heald
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720-3200, USA.
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Dell’Anno I, Melani A, Martin SA, Barbarino M, Silvestri R, Cipollini M, Giordano A, Mutti L, Nicolini A, Luzzi L, Aiello R, Gemignani F, Landi S. A Drug Screening Revealed Novel Potential Agents against Malignant Pleural Mesothelioma. Cancers (Basel) 2022; 14:2527. [PMID: 35626133 PMCID: PMC9139775 DOI: 10.3390/cancers14102527] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/08/2022] [Accepted: 05/13/2022] [Indexed: 02/04/2023] Open
Abstract
The lack of effective therapies remains one of the main challenges for malignant pleural mesothelioma (MPM). In this perspective, drug repositioning could accelerate the identification of novel treatments. We screened 1170 FDA-approved drugs on a SV40-immortalized mesothelial (MeT-5A) and five MPM (Mero-14, Mero-25, IST-Mes2, NCI-H28 and MSTO-211H) cell lines. Biological assays were carried out for 41 drugs, showing the highest cytotoxicity and for whom there were a complete lack of published literature in MPM. Cytotoxicity and caspase activation were evaluated with commercially available kits and cell proliferation was assayed using MTT assay and by clonogenic activity with standard protocols. Moreover, the five most effective drugs were further evaluated on patient-derived primary MPM cell lines. The most active molecules were cephalomannine, ouabain, alexidine, thonzonium bromide, and emetine. Except for alexidine, these drugs inhibited the clonogenic ability and caspase activation in all cancer lines tested. The proliferation was inhibited also on an extended panel of cell lines, including primary MPM cells. Thus, we suggest that cephalomannine, ouabain, thonzonium bromide, and emetine could represent novel candidates to be repurposed for improving the arsenal of therapeutic weapons in the fight against MPM.
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Affiliation(s)
- Irene Dell’Anno
- Genetic Unit, Department of Biology, University of Pisa, 56126 Pisa, Italy; (I.D.); (A.M.); (R.S.); (M.C.); (S.L.)
| | - Alessandra Melani
- Genetic Unit, Department of Biology, University of Pisa, 56126 Pisa, Italy; (I.D.); (A.M.); (R.S.); (M.C.); (S.L.)
| | - Sarah A. Martin
- Centre for Cancer Cell and Molecular Biology, Barts Cancer Institute, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK;
| | - Marcella Barbarino
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (M.B.); (A.G.)
- Translational Oncology, Center for Biotechnology, College of Science and Technology, Temple University, Sbarro Institute for Cancer Research and Molecular Medicine, Philadelphia, PA 19122, USA;
| | - Roberto Silvestri
- Genetic Unit, Department of Biology, University of Pisa, 56126 Pisa, Italy; (I.D.); (A.M.); (R.S.); (M.C.); (S.L.)
| | - Monica Cipollini
- Genetic Unit, Department of Biology, University of Pisa, 56126 Pisa, Italy; (I.D.); (A.M.); (R.S.); (M.C.); (S.L.)
| | - Antonio Giordano
- Department of Medical Biotechnologies, University of Siena, 53100 Siena, Italy; (M.B.); (A.G.)
- Translational Oncology, Center for Biotechnology, College of Science and Technology, Temple University, Sbarro Institute for Cancer Research and Molecular Medicine, Philadelphia, PA 19122, USA;
| | - Luciano Mutti
- Translational Oncology, Center for Biotechnology, College of Science and Technology, Temple University, Sbarro Institute for Cancer Research and Molecular Medicine, Philadelphia, PA 19122, USA;
| | - Andrea Nicolini
- Department of Oncology, Transplantations and New Technologies in Medicine, University of Pisa, 56126 Pisa, Italy;
| | - Luca Luzzi
- Department of Medicine, Surgery and Neurosciences, Siena University Hospital, 53100 Siena, Italy;
| | - Raffaele Aiello
- Toma Institute Srl, Via Cesare Rosaroll 24, 80139 Napoli, Italy;
| | - Federica Gemignani
- Genetic Unit, Department of Biology, University of Pisa, 56126 Pisa, Italy; (I.D.); (A.M.); (R.S.); (M.C.); (S.L.)
| | - Stefano Landi
- Genetic Unit, Department of Biology, University of Pisa, 56126 Pisa, Italy; (I.D.); (A.M.); (R.S.); (M.C.); (S.L.)
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Lin X, Luo J, Tan J, Yang L, Wang M, Li P. Experimental animal models of drug-induced sensorineural hearing loss: a narrative review. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:1393. [PMID: 34733945 PMCID: PMC8506545 DOI: 10.21037/atm-21-2508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 08/16/2021] [Indexed: 01/19/2023]
Abstract
Objective This narrative review describes experimental animal models of sensorineural hearing loss (SNHL) caused by ototoxic agents. Background SNHL primarily results from damage to the sensory organ within the inner ear or the vestibulocochlear nerve (cranial nerve VIII). The main etiology of SNHL includes genetic diseases, presbycusis, ototoxic agents, infection, and noise exposure. Animal models with functional and anatomic damage to the sensory organ within the inner ear or the vestibulocochlear nerve mimicking the damage seen in humans are employed to explore the mechanism and potential treatment of SNHL. These animal models of SNHL are commonly established using ototoxic agents. Methods A literature search of PubMed, Embase, and Web of Science was performed for research articles on hearing loss and ototoxic agents in animal models of hearing loss. Conclusions Common ototoxic medications such as aminoglycoside antibiotics (AABs) and platinum antitumor drugs are extensively used to induce SNHL in experimental animals. The effect of ototoxic agents in vivo is influenced by the chemical mechanisms of the ototoxic agents, the species of animal, routes of administration of the ototoxic agents, and the dosage of ototoxic agents. Animal models of drug-induced SNHL contribute to understanding the hearing mechanism and reveal the function of different parts of the auditory system in humans.
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Affiliation(s)
- Xuexin Lin
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Jia Luo
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Jingqian Tan
- Department of Otolaryngology Head and Neck Surgery, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, China
| | - Luoying Yang
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Mitian Wang
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University Yuedong Hospital, Meizhou, China
| | - Peng Li
- Department of Otolaryngology Head and Neck Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
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6
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Tang Z, Chen S, Ni Y, Zhao R, Zhu X, Yang X, Zhang X. Role of Na +, K +-ATPase ion pump in osteoinduction. Acta Biomater 2021; 129:293-308. [PMID: 34087440 DOI: 10.1016/j.actbio.2021.05.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 05/24/2021] [Accepted: 05/26/2021] [Indexed: 12/14/2022]
Abstract
Porous biphasic calcium phosphate bioceramic (BCP) possesses osteoinductivity to induce the osteoblastic commitment of mesenchymal stem cells (MSCs) and ectopic bone formation. However, the underlying mechanism remains enigmatic. We performed a gene array analysis of MSCs cocultured with BCP to screen for candidate osteoinductive modulators. Na+, K+-ATPase (NKA), an ion transporter, therefore was identified as a crucial ion transporter in regulating the osteogenesis of the cells. NKA activator, a polyclonal antibody, enriched the cytomembrane abundance of NKA and lead to an enhanced osteogenic effect of BCP. As indicated in gene array analysis and suggested by co-immunoprecipitation assay, protein phosphatase 2A (PP2A) was elevated by BCP to dephosphorylate NKA and prevent its endocytosis. The inhibition of NKA by ouabain resulted in an adverse effect on osteoinductivity of BCP. We further altered NKA activity in mice implanted with BCP and found that the intensity and incidence of osteoinduction was increased by the NKA activator. We went one step further by investigating the potential of targeting NKA in osteoporotic bone regeneration. Activating NKA upregulated osteogenic gene expression and calcium deposition ability of osteoporotic osteoblasts. Furthermore, activation of NKA in mice ameliorated estrogen-deficiency induced bone loss, in terms of increased bone mass and improved bending strength. With this osteoinductive bioceramic derived ion transporter target, we demonstrate that the activation of NKA has significant potential to revolutionize the regeneration of bone. STATEMENT OF SIGNIFICANCE: In this study, we identified an important role of Na+, K+-ATPase (NKA) have played in osteoinductivity of biphasic calcium phosphate bioceramic (BCP). Furthermore, we demonstrated the therapeutic potential of targeting NKA in osteoporotic bone regeneration. Numerous gene and protein targets to treat osteoporosis were discovered every year, mainly obtained by genomic and proteomic screenings of a large population. In contrast, our study identified an unrevealed bone regenerating target from the upregulated genes induced by an osteoinductive biomaterial. The approach was cost-saving since it did not require a large sample pool. Furthermore, the target derived from this approach was proven to be anabolic. Identification of an anabolic agent holds significant value since most of the current anti-osteoporotic therapies are antiresorptive.
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Mizuguchi K, Aoki H, Aoyama M, Kawaguchi Y, Waguri-Nagaya Y, Ohte N, Asai K. Three-dimensional spheroid culture induces apical-basal polarity and the original characteristics of immortalized human renal proximal tubule epithelial cells. Exp Cell Res 2021; 404:112630. [PMID: 33971195 DOI: 10.1016/j.yexcr.2021.112630] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/21/2021] [Accepted: 04/27/2021] [Indexed: 10/21/2022]
Abstract
The proximal tubules, which are part of the kidney, maintain blood homeostasis by absorbing amino acids, glucose, water, and ions such as sodium (Na), potassium, and bicarbonate. Proximal tubule dysfunction is associated with the pathogenesis of many kidney diseases. Renal proximal tubular epithelial cells (RPTECs) are responsible for the main functions of the proximal tubules. Therefore, in vitro experiments using RPTECs would greatly enhance our understanding of nephron physiology and pathobiology. It is preferable to use immortalized cell lines, such as human kidney-2 (HK-2) cells, because they are derived from humans and maintain growth indefinitely. However, tissue-specific RPTEC phenotypes, including apical-basal polarization, are frequently lost in conventional two-dimensional culture methods in part due to microenvironmental deficiencies. To overcome this limitation, we developed a three-dimensional (3D) spheroid culture method for HK-2 cells using an extracellular matrix. HK-2 spheroids in 3D culture formed a tubule-like architecture with cellular polarity and showed markedly restored Na transport function. 3D culture of HK-2 cells also increased expression of kidney development-related genes, including WNT9B. Models of human renal tubules using HK-2 spheroids will greatly improve our understanding of the physiology and pathobiology of the kidney.
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Affiliation(s)
- Ken Mizuguchi
- Department of Glial Cell Biology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan; Department of Cardiology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan.
| | - Hiromasa Aoki
- Department of Pathobiology, Nagoya City University Graduate School of Pharmaceutical Sciences, 3-1 Tanabe-dori, 25 Mizuho-ku, Nagoya, 467-8603, Japan
| | - Mineyoshi Aoyama
- Department of Pathobiology, Nagoya City University Graduate School of Pharmaceutical Sciences, 3-1 Tanabe-dori, 25 Mizuho-ku, Nagoya, 467-8603, Japan
| | - Yohei Kawaguchi
- Department of Glial Cell Biology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan; Department of Orthopaedic Surgery, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Yuko Waguri-Nagaya
- Department of Orthopaedic Surgery, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Nobuyuki Ohte
- Department of Cardiology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Kiyofumi Asai
- Department of Glial Cell Biology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan.
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Silva CID, Gonçalves-de-Albuquerque CF, Moraes BPTD, Garcia DG, Burth P. Na/K-ATPase: Their role in cell adhesion and migration in cancer. Biochimie 2021; 185:1-8. [PMID: 33713729 DOI: 10.1016/j.biochi.2021.03.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 03/03/2021] [Accepted: 03/04/2021] [Indexed: 12/18/2022]
Abstract
Na/K-ATPase (NKA) is a p-type transmembrane enzyme formed by three different subunits (α, β, and γ gamma). Primarily responsible for transporting sodium and potassium through the cell membrane, it also plays a critical role in intracellular signaling. The activation of diverse intracellular pathways may trigger cell death, survival, or even cell proliferation. Changes in the NKA functions or expression in isoforms subunits impact pathological conditions, such as cancer. The NKA function affects cell adhesion, motility, and migration, which are different in the physiological and pathological states. All enzyme subunits take part in the cell adhesion process, with the β subunit being the most studied. Thus, herein we aim to highlight NKA' central role in cell adhesion, motility, and migration in cancer cells.
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Affiliation(s)
- Camila Ignácio da Silva
- Laboratório de Enzimologia e Sinalização Celular, Departamento de Biologia Celular e Molecular, Instituto de Biologia, Universidade Federal Fluminense, Niterói, Brazil; Pós-Graduação em Ciências e Biotecnologia Universidade Federal Fluminense, Niterói, Brazil
| | - Cassiano Felippe Gonçalves-de-Albuquerque
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil; Laboratorio de Imunofarmacologia, Departamento de Bioquímica, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
| | - Bianca Portugal Tavares de Moraes
- Laboratorio de Imunofarmacologia, Departamento de Bioquímica, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Diogo Gomes Garcia
- Laboratório de Neurociências Translacional, Programa de Pós-Graduação em Neurologia, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Patrícia Burth
- Laboratório de Enzimologia e Sinalização Celular, Departamento de Biologia Celular e Molecular, Instituto de Biologia, Universidade Federal Fluminense, Niterói, Brazil; Pós-Graduação em Ciências e Biotecnologia Universidade Federal Fluminense, Niterói, Brazil.
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Schmid V, Plössl K, Schmid C, Bernklau S, Weber BHF, Friedrich U. Retinoschisin and Cardiac Glycoside Crosstalk at the Retinal Na/K-ATPase. Invest Ophthalmol Vis Sci 2020; 61:1. [PMID: 32392309 PMCID: PMC7405613 DOI: 10.1167/iovs.61.5.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Purpose Mutations in the RS1 gene, which encodes retinoschisin, cause X-linked juvenile retinoschisis, a retinal dystrophy in males. Retinoschisin specifically interacts with the retinal sodium–potassium adenosine triphosphatase (Na/K-ATPase), a transmembrane ion pump. Na/K-ATPases also bind cardiac glycosides, which control the activity of the pump and have been linked to disturbances in retinal homeostasis. In this study, we investigated the crosstalk between retinoschisin and cardiac glycosides at the retinal Na/K-ATPase and the consequences of this interplay on retinal integrity. Methods The effect of cardiac glycosides (ouabain and digoxin) on the binding of retinoschisin to the retinal Na/K-ATPase was investigated via western blot and immunocytochemistry. Also, the influence of retinoschisin on the binding of cardiac glycosides was analyzed via enzymatic assays, which quantified cardiac glycoside-sensitive Na/K-ATPase pump activity. Moreover, retinoschisin-dependent binding of tritium-labeled ouabain to the Na/K-ATPase was determined. Finally, a reciprocal effect of retinoschisin and cardiac glycosides on Na/K-ATPase localization and photoreceptor degeneration was addressed using immunohistochemistry in retinoschisin-deficient murine retinal explants. Results Cardiac glycosides displaced retinoschisin from the retinal Na/K-ATPase; however, retinoschisin did not affect cardiac glycoside binding. Notably, cardiac glycosides reduced the capacity of retinoschisin to regulate Na/K-ATPase localization and to protect against photoreceptor degeneration. Conclusions Our findings reveal opposing effects of retinoschisin and cardiac glycosides on retinal Na/K-ATPase binding and on retinal integrity, suggesting that a fine-tuned interplay between both components is required to maintain retinal homeostasis. This observation provides new insight into the mechanisms underlying the pathological effects of cardiac glycoside treatment on retinal integrity.
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Reddy D, Kumavath R, Tan TZ, Ampasala DR, Kumar AP. Peruvoside targets apoptosis and autophagy through MAPK Wnt/β-catenin and PI3K/AKT/mTOR signaling pathways in human cancers. Life Sci 2019; 241:117147. [PMID: 31830480 DOI: 10.1016/j.lfs.2019.117147] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/30/2019] [Accepted: 11/04/2019] [Indexed: 12/20/2022]
Abstract
AIM To investigate the cytotoxic effect of Peruvoside and mechanism of action in human cancers. MAIN METHODS Cell viability was measured by MTT assay and the cell cycle arrest was identified by FACS. Real-time qPCR and western blotting studies were performed to identify important gene and protein expressions in the different pathways leading to apoptosis. Immunofluorescence was performed to understand protein localization and molecular docking studies were performed to identify protein-ligand interactions. KEY FINDINGS Peruvoside showed significant anti-proliferative activities against human breast, lung, and liver cancer cells in dose-dependent manner. The anti-cancer mechanism was further confirmed by DNA damage and cell cycle arrest at the G0/G1 phase. Dysregulation of Wnt/β-catenin signaling with Peruvoside treatment resulted in inhibition of cyclin D1 and c-Myc also observed in this study. Furthermore, we identified that Peruvoside can inhibit autophagy by PI3K/AKT/mTOR signaling and through downregulating MEK1. Moreover, Peruvoside has the ability to modulate the expressions of key proteins from the cell cycle, MAPK, NF-kB, and JAK-STAT signaling. In silico studies revealed that Peruvoside has the ability to interact with crucial proteins from different biochemical signaling pathways. SIGNIFICANCE Our results demonstrated that Peruvoside has the ability to inhibit cancer cell proliferation by modulating the expression of various key proteins involved in cell cycle arrest, apoptosis, and autophagic cell death. Clinical data generated from the present study might provide a novel impetus for targeting several human cancers. Conclusively, our findings suggest that the Peruvoside possesses a broad spectrum of anticancer activity in breast, lung, and liver cancers, which provides an impetus for further investigation of the anticancer potentiality of this biomolecule.
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Affiliation(s)
- Dhanasekhar Reddy
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Tejaswini Hills, Periya (P.O), Kasaragod, Kerala 671320, India
| | - Ranjith Kumavath
- Department of Genomic Science, School of Biological Sciences, Central University of Kerala, Tejaswini Hills, Periya (P.O), Kasaragod, Kerala 671320, India.
| | - Tuan Zea Tan
- Cancer Science Institute of Singapore, National University of Singapore, Singapore
| | - Dinakara Rao Ampasala
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry 605014, India
| | - Alan Prem Kumar
- Cancer Science Institute of Singapore, National University of Singapore, Singapore; Departments of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Medical Science Cluster, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
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Menni C, McCallum L, Pietzner M, Zierer J, Aman A, Suhre K, Mohney RP, Mangino M, Friedrich N, Spector TD, Padmanabhan S. Metabolomic profiling identifies novel associations with Electrolyte and Acid-Base Homeostatic patterns. Sci Rep 2019; 9:15088. [PMID: 31636301 PMCID: PMC6803625 DOI: 10.1038/s41598-019-51492-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 10/01/2019] [Indexed: 12/17/2022] Open
Abstract
Electrolytes have a crucial role in maintaining health and their serum levels are homeostatically maintained within a narrow range by multiple pathways involving the kidneys. Here we use metabolomics profiling (592 fasting serum metabolites) to identify molecular markers and pathways associated with serum electrolyte levels in two independent population-based cohorts. We included 1523 adults from TwinsUK not on blood pressure-lowering therapy and without renal impairment to look for metabolites associated with chloride, sodium, potassium and bicarbonate by running linear mixed models adjusting for covariates and multiple comparisons. For each electrolyte, we further performed pathway enrichment analysis (PAGE algorithm). Results were replicated in an independent cohort. Chloride, potassium, bicarbonate and sodium associated with 10, 58, 36 and 17 metabolites respectively (each P < 2.1 × 10-5), mainly lipids. Of all the electrolytes, serum potassium showed the most significant associations with individual fatty acid metabolites and specific enrichment of fatty acid pathways. In contrast, serum sodium and bicarbonate showed associations predominantly with amino-acid related species. In the first study to examine systematically associations between serum electrolytes and small circulating molecules, we identified novel metabolites and metabolic pathways associated with serum electrolyte levels. The role of these metabolic pathways on electrolyte homeostasis merits further studies.
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Affiliation(s)
- Cristina Menni
- Department of Twin Research & Genetic Epidemiology, King's College London, London, UK.
| | - Linsay McCallum
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Maik Pietzner
- Institute of Clinical Chemistry and Laboratory Medicine, University Medicine Greifswald, Greifswald, Germany
- DZHK (German Center for Cardiovascular Research), partner site Greifswald, Greifswald, Germany
| | - Jonas Zierer
- Department of Twin Research & Genetic Epidemiology, King's College London, London, UK
- Department of Physiology and Biophysics, Weill Cornell Medical College in Qatar, Education City, Qatar Foundation, Doha, Qatar
| | - Alisha Aman
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | | | | | - Massimo Mangino
- Department of Twin Research & Genetic Epidemiology, King's College London, London, UK
| | - Nele Friedrich
- Institute of Clinical Chemistry and Laboratory Medicine, University Medicine Greifswald, Greifswald, Germany
| | - Tim D Spector
- Department of Twin Research & Genetic Epidemiology, King's College London, London, UK
| | - Sandosh Padmanabhan
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.
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12
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Zhang Y, Yan G, Sun C, Nan L, Wang X, Xu W, Chu K. Compound GDC, an Isocoumarin Glycoside, Protects against LPS-Induced Inflammation and Potential Mechanisms In Vitro. Inflammation 2019; 42:506-515. [PMID: 30328549 DOI: 10.1007/s10753-018-0908-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Compound 3R-(4'-hydroxyl-3'-O-β-D-glucopyranosyl phenyl)-dihydro isocoumarin (GDC) is a natural isocoumarin, recently isolated from the stems of H. paniculiflorum. However, we know little about the effects of GDC on rheumatoid arthritis (RA). This study aims to investigate the protective effects and potential mechanisms of GDC against LPS-induced inflammation in vitro. Fibroblast-like synoviocytes (FLSs) obtained from synovial tissue of rats were induced by lipopolysaccharide (LPS) and treated with GDC. Cell viability was determined by mitochondrial-respiration-dependent3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay. Secretion of various inflammatory mediators was analyzed by ELISA and RayBio® Rat Cytokine Antibody Array. Potential mechanisms that are associated with anti-inflammatory effect were examined by Western blot. Results showed that GDC significantly inhibited the production of tumor necrosis factor alpha (TNF-α) and interleukin- (IL-) 6 induced by LPS. GDC also reduced the expression of inducible nitric oxide synthase (iNOS), TNF-α, IL-6, and IL-1β, as well as proinflammatory cytokines such as activin A, ciliary neurotrophic factor (CNTF), fractalkine, IFN-γ, IL-4, and TIMP-1. Moreover, GDC inhibited LPS-induced phosphorylation of extracellular regulated protein kinases (ERK1/2), p38 mitogen-activated protein kinases (p38), c-Jun N-terminal kinase (JNK), and IκB. And GDC also blocked NF-κBp65 nuclear translocation. All the results suggested that the protective effects of GDC against LPS-induced inflammation in vitro may be related with NF-κB and JNK signaling pathway.
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Affiliation(s)
- Yuqin Zhang
- Pharmacy College of Fujian University of Traditional Chinese Medicine, Shangjie Minhou, Fuzhou, Fujian, People's Republic of China.,Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education, Hainan Normal University, Haikou, People's Republic of China.,State Key Laboratory of Chinese Pharmacies of Fujian Provincial Department of Science and Technology of Fujian University of Traditional Chinese Medicine, No. 1 Qiuyang Road, Shangjie Minhou, Fuzhou, Fujian, 350122, People's Republic of China
| | - Guohong Yan
- People's Hospital Affiliated to Fujian University of Traditional Chinese Medicine, Bayiqi Road, Fuzhou, Fujian, People's Republic of China
| | - Chengtao Sun
- Pharmacy College of Fujian University of Traditional Chinese Medicine, Shangjie Minhou, Fuzhou, Fujian, People's Republic of China.,State Key Laboratory of Chinese Pharmacies of Fujian Provincial Department of Science and Technology of Fujian University of Traditional Chinese Medicine, No. 1 Qiuyang Road, Shangjie Minhou, Fuzhou, Fujian, 350122, People's Republic of China
| | - Lihong Nan
- Pharmacy College of Fujian University of Traditional Chinese Medicine, Shangjie Minhou, Fuzhou, Fujian, People's Republic of China.,State Key Laboratory of Chinese Pharmacies of Fujian Provincial Department of Science and Technology of Fujian University of Traditional Chinese Medicine, No. 1 Qiuyang Road, Shangjie Minhou, Fuzhou, Fujian, 350122, People's Republic of China
| | - Xiaoying Wang
- Pharmacy College of Fujian University of Traditional Chinese Medicine, Shangjie Minhou, Fuzhou, Fujian, People's Republic of China.,State Key Laboratory of Chinese Pharmacies of Fujian Provincial Department of Science and Technology of Fujian University of Traditional Chinese Medicine, No. 1 Qiuyang Road, Shangjie Minhou, Fuzhou, Fujian, 350122, People's Republic of China
| | - Wei Xu
- Pharmacy College of Fujian University of Traditional Chinese Medicine, Shangjie Minhou, Fuzhou, Fujian, People's Republic of China. .,State Key Laboratory of Chinese Pharmacies of Fujian Provincial Department of Science and Technology of Fujian University of Traditional Chinese Medicine, No. 1 Qiuyang Road, Shangjie Minhou, Fuzhou, Fujian, 350122, People's Republic of China.
| | - Kedan Chu
- Pharmacy College of Fujian University of Traditional Chinese Medicine, Shangjie Minhou, Fuzhou, Fujian, People's Republic of China. .,State Key Laboratory of Chinese Pharmacies of Fujian Provincial Department of Science and Technology of Fujian University of Traditional Chinese Medicine, No. 1 Qiuyang Road, Shangjie Minhou, Fuzhou, Fujian, 350122, People's Republic of China.
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Kumari N, Singh S, Kumari V, Kumar S, Kumar V, Kumar A. Ouabain potentiates the antimicrobial activity of aminoglycosides against Staphylococcus aureus. Altern Ther Health Med 2019; 19:119. [PMID: 31170971 PMCID: PMC6554875 DOI: 10.1186/s12906-019-2532-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 05/29/2019] [Indexed: 01/30/2023]
Abstract
Background Staphylococcus aureus is a notorious pathogen which often causes nosocomial and community attained infections. These infections steadily increased after evolving the resistance due to indecorous practice of antibiotics and now become a serious health issue. Ouabain is a Na+/K+-ATPase inhibitor that leads to increase the heart contraction in patients with congestive heart failure. Methods In the present study, in vitro antimicrobial effect of ouabain together with aminoglycosides was determined against clinical and non-clinical S. aureus strains. Using checkerboard, Gentamycin uptake and biofilm assays, we analysed he interactions of ouabain with aminoglycosides. Results Ouabain induced the staphylocidal potency of aminoglycosides by remarkably reducing the MIC of gentamycin (GEN) by 16 (0.25 μg/mL), 8 folds (0.5 μg/mL) amikacin (AMK); and 16 folds (1.0 μg/mL) with kanamycin (KAN), compared to their individual doses. OBN severely reduced cell viability within 60 min with GEN (1 μg/mL), KAN (2 μg/mL) and 90 min with AMK (1 μg/mL). This bactericidal effect was enhanced due to GEN uptake potentiated by 66% which led to increase the cell permeability as revealed by leakage of bacterial ATP and nitrocefin assay. The biofilm adherence disrupted by 80 and 50% at 5 mg/mL and 1.5 mg/mL OBN and 50 and 90% biofilm formation was inhibited at 5 mg/mL (MBIC50) and 10 mg/mL (MBIC90), respectively. Moreover, OBN with GEN further induced biofilm inhibition by 67 ± 5% at pH 7.0. Conclusions Taken together, we established that OBN synergizes the antimicrobial activity of aminoglycosides that induces cell killing due to intracellular accumulation of GEN by disturbing cell homeostasis. It may be proven an effective approach for the treatment of staphylococcal infections.
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Interaction of ouabain and progesterone on induction of bull sperm capacitation. Theriogenology 2019; 126:191-198. [DOI: 10.1016/j.theriogenology.2018.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 11/06/2018] [Accepted: 12/01/2018] [Indexed: 01/16/2023]
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Ouabain Does Not Induce Selective Spiral Ganglion Cell Degeneration in Guinea Pigs. BIOMED RESEARCH INTERNATIONAL 2018; 2018:1568414. [PMID: 30151372 PMCID: PMC6091334 DOI: 10.1155/2018/1568414] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 05/24/2018] [Accepted: 06/28/2018] [Indexed: 11/17/2022]
Abstract
Round window membrane (RWM) application of ouabain is known to selectively destroy type I spiral ganglion cells (SGCs) in cochleas of several rodent species, while leaving hair cells intact. This protocol has been used in rats and Mongolian gerbils, but observations in the guinea pig are conflicting. This is why we reinvestigated the effect of ouabain on the guinea pig cochlea. Ouabain solutions of different concentrations were placed, in a piece of gelfoam, upon the RWM of the right cochleas. Auditory function was assessed using acoustically evoked auditory brainstem responses (aABR). Finally, cochleas were fixed and processed for histological examination. Due to variability within treatment groups, histological data was pooled and three categories based upon general histological observations were defined: cochleas without outer hair cell (OHC) and SGC loss (Category 1), cochleas with OHC loss only (Category 2), and cochleas with OHC and SGC loss (Category 3). Animals treated with 1 mM or 10 mM ouabain showed shifts in hearing thresholds, corresponding with varying histological changes in their cochleas. Most cochleas exhibited complete outer hair cell loss in the basal and middle turns, while some had no changes, together with either moderate or near-complete loss of SGCs. Neither loss of inner hair cells nor histological changes of the stria vascularis were observed in any of the animals. Cochleas in Category 1 had normal aABRs and morphology. On average, in Category 2 OHC loss was 46.0±5.7%, SGC loss was below threshold, ABR threshold shift was 44.9±2.7 dB, and ABR wave II amplitude was decreased by 17.1±3.8 dB. In Category 3 OHC loss was 68.3±6.9%, SGC loss was 49.4±4.3%, ABR threshold shift was 39.0±2.4 dB, and ABR amplitude was decreased by 15.8±1.6 dB. Our results show that ouabain does not solely destroy type I SGCs in the guinea pig cochlea.
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Endogenous Ouabain and Related Genes in the Translation from Hypertension to Renal Diseases. Int J Mol Sci 2018; 19:ijms19071948. [PMID: 29970843 PMCID: PMC6073363 DOI: 10.3390/ijms19071948] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/28/2018] [Accepted: 06/29/2018] [Indexed: 01/22/2023] Open
Abstract
The endogenous ouabain (EO) is a steroid hormone secreted by the adrenal gland with cardio-tonic effects. In this article, we have reviewed and summarized the most recent reports about EO, particularly with regard to how it may interact with specific genetic backgrounds. We have focused our attention on the EO’s potential pathogenic role in several diseases, including renal failure, essential hypertension and heart failure. Notably, these reports have demonstrated that EO acts as a pro-hypertrophic and growth-promoting hormone, which might lead to a cardiac remodeling affecting cardiovascular functions and structures. In addition, a possible role of EO in the development of acute kidney injury has been hypothesized. During the last decays, many important improvements permitted a deeper understanding of EO’s metabolisms and functions, including the characteristics of its receptor and the effects of its activation. Such progresses indicated that EO has significant implications in the pathogenesis of many common diseases. The patho-physiological role of EO in the development of hypertension and other cardiac and renal complications have laid the basis for the development of a new selective compound that could selectively modulate the genetic and molecular mechanisms involved in EO’s action. It is evident that the knowledge of EO has incredibly increased; however, many important areas remain to be further investigated.
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Trenti A, Zulato E, Pasqualini L, Indraccolo S, Bolego C, Trevisi L. Therapeutic concentrations of digitoxin inhibit endothelial focal adhesion kinase and angiogenesis induced by different growth factors. Br J Pharmacol 2017; 174:3094-3106. [PMID: 28688145 DOI: 10.1111/bph.13944] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 06/23/2017] [Accepted: 06/27/2017] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Cardiac glycosides are Na+ /K+ -ATPases inhibitors used to treat congestive heart failure and cardiac arrhythmias. Epidemiological studies indicate that patients on digitalis therapy are more protected from cancer. Evidence of a selective cytotoxicity against cancer cells has suggested their potential use as anticancer drugs. The effect on angiogenesis of clinically used cardiac glycosides has not been extensively explored. EXPERIMENTAL APPROACH We studied the effect of digoxin, digitoxin and ouabain on early events of the angiogenic process in HUVECs. We determined HUVEC viability, proliferation, migration and differentiation into capillary tube-like structures. We also tested drug activity using an in vivo angiogenesis model. Activation of protein tyrosine kinase 2 (FAK) and signalling proteins associated with the Na+ /K+ -ATPase signalosome was determined by Western blotting. KEY RESULTS Digitoxin and ouabain (1-100 nM) inhibited HUVEC migration, concentration-dependently, without affecting cell viability, while digoxin induced apoptosis at the same concentrations. Digitoxin antagonized growth factor-induced migration and tubularization at concentrations (1-25 nM) within its plasma therapeutic range. The anti-angiogenic effect of digitoxin was confirmed also by in vivo studies. Digitoxin induced Src, Akt and ERK1/2 phosphorylation but did not affect FAK autophosphorylation at Tyr397 . However, it significantly inhibited growth factor-induced FAK phosphorylation at Tyr576/577 . CONCLUSIONS AND IMPLICATIONS Therapeutic concentrations of digitoxin inhibited angiogenesis and FAK activation by several pro-angiogenic stimuli. These novel findings suggest a potential repositioning of digitoxin as a broad-spectrum anti-angiogenic drug for diseases where pathological angiogenesis is involved.
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Affiliation(s)
- Annalisa Trenti
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy
| | | | | | | | - Chiara Bolego
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy
| | - Lucia Trevisi
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy
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On the Many Actions of Ouabain: Pro-Cystogenic Effects in Autosomal Dominant Polycystic Kidney Disease. Molecules 2017; 22:molecules22050729. [PMID: 28467389 PMCID: PMC5688955 DOI: 10.3390/molecules22050729] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 04/19/2017] [Accepted: 04/30/2017] [Indexed: 02/07/2023] Open
Abstract
Ouabain and other cardenolides are steroidal compounds originally discovered in plants. Cardenolides were first used as poisons, but after finding their beneficial cardiotonic effects, they were rapidly included in the medical pharmacopeia. The use of cardenolides to treat congestive heart failure remained empirical for centuries and only relatively recently, their mechanisms of action became better understood. A breakthrough came with the discovery that ouabain and other cardenolides exist as endogenous compounds that circulate in the bloodstream of mammals. This elevated these compounds to the category of hormones and opened new lines of investigation directed to further study their biological role. Another important discovery was the finding that the effect of ouabain was mediated not only by inhibition of the activity of the Na,K-ATPase (NKA), but by the unexpected role of NKA as a receptor and a signal transducer, which activates a complex cascade of intracellular second messengers in the cell. This broadened the interest for ouabain and showed that it exerts actions that go beyond its cardiotonic effect. It is now clear that ouabain regulates multiple cell functions, including cell proliferation and hypertrophy, apoptosis, cell adhesion, cell migration, and cell metabolism in a cell and tissue type specific manner. This review article focuses on the cardenolide ouabain and discusses its various in vitro and in vivo effects, its role as an endogenous compound, its mechanisms of action, and its potential use as a therapeutic agent; placing especial emphasis on our findings of ouabain as a pro-cystogenic agent in autosomal dominant polycystic kidney disease (ADPKD).
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Abstract
Since the beginning of investigations of the Na,K-ATPase, it has been well-known that Mg2+ is an essential cofactor for activation of enzymatic ATP hydrolysis without being transported through the cell membrane. Moreover, experimental evidence has been collected through the years that shows that Mg2+ ions have a regulatory effect on ion transport by interacting with the cytoplasmic side of the ion pump. Our experiments allowed us to reveal the underlying mechanism. Mg2+ is able to bind to a site outside the membrane domain of the protein's α subunit, close to the entrance of the access channel to the ion-binding sites, thus modifying the local concentration of the ions in the electrolyte, of which Na+, K+, and H+ are of physiological interest. The decrease in the concentration of these cations can be explained by electrostatic interaction and estimated by the Debye-Hückel theory. This effect provokes the observed apparent reduction of the binding affinity of the binding sites of the Na,K-ATPase in the presence of various Mg2+ concentrations. The presence of the bound Mg2+, however, does not affect the reaction kinetics of the transport function of the ion pump. Therefore, stopped-flow experiments could be performed to gain the first insight into the Na+ binding kinetics on the cytoplasmic side by Mg2+ concentration jump experiments.
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Affiliation(s)
- Hans-Jürgen Apell
- Department of Biology, University of Konstanz , 78464 Konstanz, Germany
| | - Tanja Hitzler
- Department of Biology, University of Konstanz , 78464 Konstanz, Germany
| | - Grischa Schreiber
- Department of Biology, University of Konstanz , 78464 Konstanz, Germany
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Meng L, Wen Y, Zhou M, Li J, Wang T, Xu P, Ouyang J. Ouabain induces apoptosis and autophagy in Burkitt's lymphoma Raji cells. Biomed Pharmacother 2016; 84:1841-1848. [PMID: 27894666 DOI: 10.1016/j.biopha.2016.10.114] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 10/21/2016] [Accepted: 10/31/2016] [Indexed: 12/31/2022] Open
Abstract
The steroid Na+/K+-ATPase blocker ouabain has been shown to exhibit cytotoxic effects in various tumor cell systems. This study aimed to determine the effects of ouabain on Burkitt's lymphoma Raji cells. Ouabain treatment of Raji cells significantly inhibited cell proliferation in a dose-dependent manner and increased the morphological changes associated with apoptosis. Additionally, increased numbers of both early and late apoptotic cells were observed by annexin V-FITC/PI flow cytometry assay. Increased levels of caspase-3 and cleaved-caspase-3, higher Bax activity and decreased expression of the anti-apoptotic protein Bcl-2 were detected in ouabain-treated Raji cells. Vacuole accumulation was also observed in transmission electron microscope (TEM) images of ouabain-treated Raji cells, indicating that these cells were undergoing autophagy. Expression of the autophagy-related proteins LC3-II and Beclin-1 was upregulated in ouabain-treated Raji cells. These results suggest that ouabain may promote cell death in Raji cells by inducing pathways associated with apoptosis and autophagy. Our study also provides novel evidence that ouabain may be an effective agent for treating Burkitt's lymphoma.
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Affiliation(s)
- Li Meng
- Department of Hematology, Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Yanting Wen
- Department of Pathology, Nanjing University Medical School, Nanjing, China
| | - Min Zhou
- Department of Hematology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Jian Li
- Department of Hematology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Ting Wang
- Department of Hematology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Peipei Xu
- Department of Hematology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Jian Ouyang
- Department of Hematology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China.
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Why Whip the Starving Horse When There Are Oats for the Starving Myocardium? Am J Ther 2016; 23:e1182-7. [PMID: 25259953 DOI: 10.1097/mjt.0000000000000151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Digoxin is the oldest drug for treatment of heart failure still in clinical use. Despite over 200 years of clinical experience with this drug, the optimal serum concentration required for both efficacy and safety remains unknown. It has been suggested that low doses have more favorable effects than higher ones. Cardiac glycosides act on the Na/K-ATPase (NKA). They show an inverted U-shaped dose-response curve with inhibition of pumping at high concentrations while increasing NKA activity at low concentrations. The classical sigmoidal dose-response curve describing an inhibition of the NKA by cardiac glycosides cannot explain this stimulatory effect. Cardiac glycosides are prototypical examples of hormetic substances. Biphasic dose-response curves of cardiac glycosides are also found in their neurohormonal effects. In low concentrations, vagomimetic effects are observed, whereas in high concentrations, sympathomimetic effects dominate. Lipophilic Digitalis glycosides have greater sympathomimetic effects; hydrophilic Strophanthus glycosides have greater vagomimetic effects. For digoxin, as a strong inotrope, there is evidence of only weak modulation of the autonomic nervous system. In ouabain, the modulation of the autonomic nervous system prevails over weak inotropic effects. Vagomimetic and sympatholytic effects characterize the therapeutic effects. In contrast to those of digoxin, the therapeutic effects of ouabain follow exactly the measurable serum concentration. Contrary to common prejudice ouabain is suitable for oral administration. Timely adjustments of dosage to patient therapeutic needs are easy to achieve with orally administered ouabain. Ouabain has the potential to crucially improve our arsenal of heart failure medications. Therefore, a clinical re-evaluation of ouabain is warranted. Randomized double-blind prospective clinical studies with ouabain, which meet today's standards, are worthwhile and necessary.
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Magalhães D, Cabral JM, Soares-da-Silva P, Magro F. Role of epithelial ion transports in inflammatory bowel disease. Am J Physiol Gastrointest Liver Physiol 2016; 310:G460-76. [PMID: 26744474 DOI: 10.1152/ajpgi.00369.2015] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 01/02/2016] [Indexed: 02/06/2023]
Abstract
Inflammatory bowel disease (IBD) is a chronic inflammatory disorder with a complex pathogenesis. Diarrhea is a highly prevalent and often debilitating symptom of IBD patients that results, at least in part, from an intestinal hydroelectrolytic imbalance. Evidence suggests that reduced electrolyte absorption is more relevant than increased secretion to this disequilibrium. This systematic review analyses and integrates the current evidence on the roles of epithelial Na(+)-K(+)-ATPase (NKA), Na(+)/H(+) exchangers (NHEs), epithelial Na(+) channels (ENaC), and K(+) channels (KC) in IBD-associated diarrhea. NKA is the key driving force of the transepithelial ionic transport and its activity is decreased in IBD. In addition, the downregulation of apical NHE and ENaC and the upregulation of apical large-conductance KC all contribute to the IBD-associated diarrhea by lowering sodium absorption and/or increasing potassium secretion.
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Affiliation(s)
- Diogo Magalhães
- Department of Pharmacology and Therapeutics, Faculty of Medicine, Porto, Portugal; and MedInUP-Center for Drug Discovery and Innovative Medicines, University of Porto, Porto, Portugal
| | - José Miguel Cabral
- Department of Pharmacology and Therapeutics, Faculty of Medicine, Porto, Portugal; and MedInUP-Center for Drug Discovery and Innovative Medicines, University of Porto, Porto, Portugal
| | - Patrício Soares-da-Silva
- Department of Pharmacology and Therapeutics, Faculty of Medicine, Porto, Portugal; and MedInUP-Center for Drug Discovery and Innovative Medicines, University of Porto, Porto, Portugal
| | - Fernando Magro
- Department of Pharmacology and Therapeutics, Faculty of Medicine, Porto, Portugal; and MedInUP-Center for Drug Discovery and Innovative Medicines, University of Porto, Porto, Portugal
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Venugopal J, Blanco G. Ouabain Enhances ADPKD Cell Apoptosis via the Intrinsic Pathway. Front Physiol 2016; 7:107. [PMID: 27047392 PMCID: PMC4805603 DOI: 10.3389/fphys.2016.00107] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 03/07/2016] [Indexed: 11/13/2022] Open
Abstract
Progression of autosomal dominant polycystic kidney disease (ADPKD) is highly influenced by factors circulating in blood. We have shown that the hormone ouabain enhances several characteristics of the ADPKD cystic phenotype, including the rate of cell proliferation, fluid secretion and the capacity of the cells to form cysts. In this work, we found that physiological levels of ouabain (3 nM) also promote programmed cell death of renal epithelial cells obtained from kidney cysts of patients with ADPKD (ADPKD cells). This was determined by Alexa Fluor 488 labeled-Annexin-V staining and TUNEL assay, both biochemical markers of apoptosis. Ouabain-induced apoptosis also takes place when ADPKD cell growth is blocked; suggesting that the effect is not secondary to the stimulatory actions of ouabain on cell proliferation. Ouabain alters the expression of BCL family of proteins, reducing BCL-2 and increasing BAX expression levels, anti- and pro-apoptotic mediators respectively. In addition, ouabain caused the release of cytochrome c from mitochondria. Moreover, ouabain activates caspase-3, a key “executioner” caspase in the cell apoptotic pathway, but did not affect caspase-8. This suggests that ouabain triggers ADPKD cell apoptosis by stimulating the intrinsic, but not the extrinsic pathway of programmed cell death. The apoptotic effects of ouabain are specific for ADPKD cells and do not occur in normal human kidney cells (NHK cells). Taken together with our previous observations, these results show that ouabain causes an imbalance in cell growth/death, to favor growth of the cystic cells. This event, characteristic of ADPKD, further suggests the importance of ouabain as a circulating factor that promotes ADPKD progression.
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Affiliation(s)
- Jessica Venugopal
- Department of Molecular and Integrative Physiology and The Kidney Institute, University of Kansas Medical Center Kansas City, KS, USA
| | - Gustavo Blanco
- Department of Molecular and Integrative Physiology and The Kidney Institute, University of Kansas Medical Center Kansas City, KS, USA
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Durlacher CT, Chow K, Chen XW, He ZX, Zhang X, Yang T, Zhou SF. Targeting Na⁺/K⁺ -translocating adenosine triphosphatase in cancer treatment. Clin Exp Pharmacol Physiol 2016; 42:427-43. [PMID: 25739707 DOI: 10.1111/1440-1681.12385] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 02/09/2015] [Accepted: 02/21/2015] [Indexed: 12/24/2022]
Abstract
The Na(+) /K(+) -translocating adenosine triphosphatase (ATPase) transports sodium and potassium across the plasma membrane and represents a potential target in cancer chemotherapy. Na(+) /K(+) -ATPase belongs to the P-type ATPase family (also known as E1-E2 ATPase), which is involved in transporting certain ions, metals, and lipids across the plasma membrane of mammalian cells. In humans, the Na(+) /K(+) -ATPase is a binary complex of an α-subunit that has four isoforms (α1 -α4 ) and a β-subunit that has three isoforms (β1 -β3 ). This review aims to update our knowledge on the role of Na(+) /K(+) -ATPase in cancer development and metastasis, as well as on how Na(+) /K(+) -ATPase inhibitors kill tumour cells. The Na(+) /K(+) -ATPase has been found to be associated with cancer initiation, growth, development, and metastasis. Cardiac glycosides have exhibited anticancer effects in cell-based and mouse studies via inhibition of the Na(+) /K(+) -ATPase and other mechanisms. Na(+) /K(+) -ATPase inhibitors may kill cancer cells via induction of apoptosis and autophagy, radical oxygen species production, and cell cycle arrest. They also modulate multiple signalling pathways that regulate cancer cell survival and death, which contributes to their antiproliferative activities in cancer cells. The clinical evidence supporting the use of Na(+) /K(+) -ATPase inhibitors as anticancer drugs is weak. Several phase I and phase II clinical trials with digoxin, Anvirzel, and huachansu (an intravenous formulated extract of the venom of the wild toad), either alone or more often in combination with other anticancer agents, have shown acceptable safety profiles but limited efficacy in cancer patients. Well-designed randomized clinical trials with reasonable sample sizes are certainly warranted to confirm the efficacy and safety of cardiac glycosides for the treatment of cancer.
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Affiliation(s)
- Cameron T Durlacher
- Department of Pharmaceutical Science, College of Pharmacy, University of South Florida, Tampa, FL, USA
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25
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Li Z, Langhans SA. Transcriptional regulators of Na,K-ATPase subunits. Front Cell Dev Biol 2015; 3:66. [PMID: 26579519 PMCID: PMC4620432 DOI: 10.3389/fcell.2015.00066] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 10/05/2015] [Indexed: 12/20/2022] Open
Abstract
The Na,K-ATPase classically serves as an ion pump creating an electrochemical gradient across the plasma membrane that is essential for transepithelial transport, nutrient uptake and membrane potential. In addition, Na,K-ATPase also functions as a receptor, a signal transducer and a cell adhesion molecule. With such diverse roles, it is understandable that the Na,K-ATPase subunits, the catalytic α-subunit, the β-subunit and the FXYD proteins, are controlled extensively during development and to accommodate physiological needs. The spatial and temporal expression of Na,K-ATPase is partially regulated at the transcriptional level. Numerous transcription factors, hormones, growth factors, lipids, and extracellular stimuli modulate the transcription of the Na,K-ATPase subunits. Moreover, epigenetic mechanisms also contribute to the regulation of Na,K-ATPase expression. With the ever growing knowledge about diseases associated with the malfunction of Na,K-ATPase, this review aims at summarizing the best-characterized transcription regulators that modulate Na,K-ATPase subunit levels. As abnormal expression of Na,K-ATPase subunits has been observed in many carcinoma, we will also discuss transcription factors that are associated with epithelial-mesenchymal transition, a crucial step in the progression of many tumors to malignant disease.
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Affiliation(s)
- Zhiqin Li
- Nemours Center for Childhood Cancer Research, Nemours/Alfred I. duPont Hospital for Children Wilmington, DE, USA
| | - Sigrid A Langhans
- Nemours Center for Childhood Cancer Research, Nemours/Alfred I. duPont Hospital for Children Wilmington, DE, USA
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26
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Chauvet S, Boonen M, Chevallet M, Jarvis L, Abebe A, Benharouga M, Faller P, Jadot M, Bouron A. The Na+/K+-ATPase and the amyloid-beta peptide aβ1-40 control the cellular distribution, abundance and activity of TRPC6 channels. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:2957-65. [PMID: 26348127 DOI: 10.1016/j.bbamcr.2015.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 08/31/2015] [Accepted: 09/03/2015] [Indexed: 11/19/2022]
Abstract
The Na(+)/K(+)-ATPase interacts with the non-selective cation channels TRPC6 but the functional consequences of this association are unknown. Experiments performed with HEK cells over-expressing TRPC6 channels showed that inhibiting the activity of the Na(+)/K(+)-ATPase with ouabain reduced the amount of TRPC6 proteins and depressed Ca(2+) entry through TRPC6. This effect, not mimicked by membrane depolarization with KCl, was abolished by sucrose and bafilomycin-A, and was partially sensitive to the intracellular Ca(2+) chelator BAPTA/AM. Biotinylation and subcellular fractionation experiments showed that ouabain caused a multifaceted redistribution of TRPC6 to the plasma membrane and to an endo/lysosomal compartment where they were degraded. The amyloid beta peptide Aβ(1-40), another inhibitor of the Na(+)/K(+)-ATPase, but not the shorter peptide Aβ1-16, reduced TRPC6 protein levels and depressed TRPC6-mediated responses. In cortical neurons from embryonic mice, ouabain, veratridine (an opener of voltage-gated Na(+) channel), and Aβ(1-40) reduced TRPC6-mediated Ca(2+) responses whereas Aβ(1-16) was ineffective. Furthermore, when Aβ(1-40) was co-added together with zinc acetate it could no longer control TRPC6 activity. Altogether, this work shows the existence of a functional coupling between the Na(+)/K(+)-ATPase and TRPC6. It also suggests that the abundance, distribution and activity of TRPC6 can be regulated by cardiotonic steroids like ouabain and the naturally occurring peptide Aβ(1-40) which underlines the pathophysiological significance of these processes.
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Affiliation(s)
- Sylvain Chauvet
- Université Grenoble Alpes, F-38000 Grenoble, France; CNRS, F-38000 Grenoble, France; CEA, iRTSV-LCBM, F-38000 Grenoble, France
| | - Marielle Boonen
- URPhyM-Laboratoire de Chimie Physiologique, University of Namur, Belgium
| | - Mireille Chevallet
- Université Grenoble Alpes, F-38000 Grenoble, France; CNRS, F-38000 Grenoble, France; CEA, iRTSV-LCBM, F-38000 Grenoble, France
| | - Louis Jarvis
- Université Grenoble Alpes, F-38000 Grenoble, France; CNRS, F-38000 Grenoble, France; CEA, iRTSV-LCBM, F-38000 Grenoble, France
| | - Addis Abebe
- Université Grenoble Alpes, F-38000 Grenoble, France; CNRS, F-38000 Grenoble, France; CEA, iRTSV-LCBM, F-38000 Grenoble, France
| | - Mohamed Benharouga
- Université Grenoble Alpes, F-38000 Grenoble, France; CNRS, F-38000 Grenoble, France; CEA, iRTSV-LCBM, F-38000 Grenoble, France
| | - Peter Faller
- CNRS, Laboratoire de Chimie de Coordination, Toulouse, France
| | - Michel Jadot
- URPhyM-Laboratoire de Chimie Physiologique, University of Namur, Belgium
| | - Alexandre Bouron
- Université Grenoble Alpes, F-38000 Grenoble, France; CNRS, F-38000 Grenoble, France; CEA, iRTSV-LCBM, F-38000 Grenoble, France.
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Jansson K, Venugopal J, Sánchez G, Magenheimer BS, Reif GA, Wallace DP, Calvet JP, Blanco G. Ouabain Regulates CFTR-Mediated Anion Secretion and Na,K-ATPase Transport in ADPKD Cells. J Membr Biol 2015; 248:1145-57. [PMID: 26289599 DOI: 10.1007/s00232-015-9832-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 08/06/2015] [Indexed: 01/16/2023]
Abstract
Cyst enlargement in autosomal dominant polycystic kidney disease (ADPKD) requires the transepithelial secretion of fluid into the cyst lumen. We previously showed that physiological amounts of ouabain enhance cAMP-dependent fluid secretion and cyst growth of human ADPKD cyst epithelial cells in culture and formation of cyst-like dilations in metanephric kidneys from Pkd1 mutant mice. Here, we investigated the mechanisms by which ouabain promotes cAMP-dependent fluid secretion and cystogenesis. Ouabain (3 nM) enhanced cAMP-induced cyst-like dilations in embryonic kidneys from Pkd1 (m1Bei) mice, but had no effect on metanephroi from Pkd1 (m1Bei) mice that lack expression of the cystic fibrosis transmembrane conductance regulator (CFTR). Similarly, ouabain stimulation of cAMP-induced fluid secretion and in vitro cyst growth of ADPKD cells were abrogated by CFTR inhibition, showing that CFTR is required for ouabain effects on ADPKD fluid secretion. Moreover, ouabain directly enhanced the cAMP-dependent Cl(-) efflux mediated by CFTR in ADPKD monolayers. Ouabain increased the trafficking of CFTR to the plasma membrane and up-regulated the expression of the CFTR activator PDZK1. Finally, ouabain decreased plasma membrane expression and activity of the Na,K-ATPase in ADPKD cells. Altogether, these results show that ouabain enhances net fluid secretion and cyst formation by activating apical anion secretion via CFTR and decreasing basolateral Na(+) transport via Na,K-ATPase. These results provide new information on the mechanisms by which ouabain affects ADPKD cells and further highlight the importance of ouabain as a non-genomic stimulator of cystogenesis in ADPKD.
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Affiliation(s)
- Kyle Jansson
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Jessica Venugopal
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Gladis Sánchez
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Brenda S Magenheimer
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Gail A Reif
- Department of Medicine, University of Kansas Medical Center, Kansas City, KS, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Darren P Wallace
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA.,Department of Medicine, University of Kansas Medical Center, Kansas City, KS, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - James P Calvet
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, USA.,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA
| | - Gustavo Blanco
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, USA. .,The Kidney Institute, University of Kansas Medical Center, Kansas City, KS, USA.
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Gao Y, Peterson S, Masri B, Hougland MT, Adham N, Gyertyán I, Kiss B, Caron MG, El-Mallakh RS. Cariprazine exerts antimanic properties and interferes with dopamine D2 receptor β-arrestin interactions. Pharmacol Res Perspect 2014; 3:e00073. [PMID: 25692006 PMCID: PMC4317219 DOI: 10.1002/prp2.73] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 02/11/2014] [Accepted: 02/19/2014] [Indexed: 12/27/2022] Open
Abstract
Activation of dopamine D2 receptors (D2R) modulates G protein/cAMP-dependent signaling and also engages Akt-GSK-3 signaling through D2R/β-arrestin 2 scaffolding of Akt and PP2A. This G protein-independent pathway may be important in mediating the antimanic effects of mood stabilizers and antipsychotics. The mood stabilizer lithium influences behavior and Akt/GSK-3 signaling in mice and many antipsychotics have been shown to more potently antagonize the activity of the β-arrestin-2 pathway relative to the G protein-dependent pathway. Cariprazine, an antipsychotic with potent D3R/D2R partial agonist activity and preferential binding to D3R, was investigated for its effects on the mediators of D2R pathways in vitro and its efficacy in animal models of mania. Effects on G protein-dependent activity were measured via inhibition of isoproterenol-induced cAMP production; effects on D2R/β-arrestin 2 signaling were determined using bioluminescence resonance energy transfer (BRET). Cariprazine was tested in vivo for antimanic-like activity, using the ouabain-induced hyperactivity model in rats. Cariprazine was more potent than aripiprazole in inhibiting isoproterenol-induced cAMP although both compounds showed similar maximum efficacy. In assays of D2R/β-arrestin 2-dependent interactions, cariprazine showed very weak partial agonist activity, unless the levels of receptor kinase were increased; as an antagonist it showed similar potency to haloperidol and ∼fivefold greater potency than aripiprazole. In an animal model of mania, cariprazine showed similar efficacy as lithium in attenuating the effects of ouabain-induced hyperactivity. In summary, the differential effects of cariprazine on D2R G protein and β-arrestin 2 mediators of signal transduction pathways could contribute to its potent antimanic-like activity.
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Affiliation(s)
- Yonglin Gao
- Mood Disorders Research Program, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine MedCenter One, 501 East Broadway, Suite 340, Louisville, Kentucky, 40202
| | - Sean Peterson
- Mood Disorders Research Program, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine MedCenter One, 501 East Broadway, Suite 340, Louisville, Kentucky, 40202
| | - Bernard Masri
- Mood Disorders Research Program, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine MedCenter One, 501 East Broadway, Suite 340, Louisville, Kentucky, 40202
| | - M Tyler Hougland
- Mood Disorders Research Program, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine MedCenter One, 501 East Broadway, Suite 340, Louisville, Kentucky, 40202
| | - Nika Adham
- Mood Disorders Research Program, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine MedCenter One, 501 East Broadway, Suite 340, Louisville, Kentucky, 40202
| | - Istvan Gyertyán
- Mood Disorders Research Program, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine MedCenter One, 501 East Broadway, Suite 340, Louisville, Kentucky, 40202
| | - Béla Kiss
- Mood Disorders Research Program, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine MedCenter One, 501 East Broadway, Suite 340, Louisville, Kentucky, 40202
| | - Marc G Caron
- Mood Disorders Research Program, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine MedCenter One, 501 East Broadway, Suite 340, Louisville, Kentucky, 40202
| | - Rif S El-Mallakh
- Mood Disorders Research Program, Department of Psychiatry and Behavioral Sciences, University of Louisville School of Medicine MedCenter One, 501 East Broadway, Suite 340, Louisville, Kentucky, 40202
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29
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Dvela-Levitt M, Cohen-Ben Ami H, Rosen H, Ornoy A, Hochner-Celnikier D, Granat M, Lichtstein D. Reduction in maternal circulating ouabain impairs offspring growth and kidney development. J Am Soc Nephrol 2014; 26:1103-14. [PMID: 25294233 DOI: 10.1681/asn.2014020130] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 08/13/2014] [Indexed: 12/20/2022] Open
Abstract
Ouabain, a steroid present in the circulation and in various tissues, was shown to affect the growth and viability of various cells in culture. To test for the possible influence of this steroid on growth and viability in vivo, we investigated the involvement of maternal circulating ouabain in the regulation of fetal growth and organ development. We show that intraperitoneal administration of anti-ouabain antibodies to pregnant mice resulted in a >80% decline in the circulating ouabain level. This reduction caused a significant decrease in offspring body weight, accompanied by enlargement of the offspring heart and inhibition of kidney and liver growth. Kidney growth inhibition was manifested by a decrease in the size and number of nephrons. After the reduction in maternal circulating ouabain, kidney expression of cyclin D1 was reduced and the expression of the α1 isoform of the Na(+), K(+)-ATPase was increased. In addition, the elevation of proliferation signals including ERK1/2, p-90RSK, Akt, PCNA, and Ki-67, and a reduction in apoptotic factors such as Bax, caspase-3, and TUNEL were detected. During human pregnancy, the circulating maternal ouabain level increased and the highest concentration of the steroid was found in the placenta. Furthermore, circulating ouabain levels in women with small-for-gestational age neonates were significantly lower than the levels in women with normal-for-gestational age newborns. These results support the notion that ouabain is a growth factor and suggest that a reduction in the concentration of this hormone during pregnancy may increase the risk of impaired growth and kidney development.
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Affiliation(s)
- Moran Dvela-Levitt
- Departments of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Hagit Cohen-Ben Ami
- Departments of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Haim Rosen
- Microbiology and Molecular Genetics, and Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Asher Ornoy
- Departments of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | | | | | - David Lichtstein
- Departments of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
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30
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Cherniavsky-Lev M, Golani O, Karlish SJD, Garty H. Ouabain-induced internalization and lysosomal degradation of the Na+/K+-ATPase. J Biol Chem 2013; 289:1049-59. [PMID: 24275648 DOI: 10.1074/jbc.m113.517003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Internalization of the Na(+)/K(+)-ATPase (the Na(+) pump) has been studied in the human lung carcinoma cell line H1299 that expresses YFP-tagged α1 from its normal genomic localization. Both real-time imaging and surface biotinylation have demonstrated internalization of α1 induced by ≥100 nm ouabain which occurs in a time scale of hours. Unlike previous studies in other systems, the ouabain-induced internalization was insensitive to Src or PI3K inhibitors. Accumulation of α1 in the cells could be augmented by inhibition of lysosomal degradation but not by proteosomal inhibitors. In agreement, the internalized α1 could be colocalized with the lysosomal marker LAMP1 but not with Golgi or nuclear markers. In principle, internalization could be triggered by a conformational change of the ouabain-bound Na(+)/K(+)-ATPase molecule or more generally by the disruption of cation homeostasis (Na(+), K(+), Ca(2+)) due to the partial inhibition of active Na(+) and K(+) transport. Overexpression of ouabain-insensitive rat α1 failed to inhibit internalization of human α1 expressed in the same cells. In addition, incubating cells in a K(+)-free medium did not induce internalization of the pump or affect the response to ouabain. Thus, internalization is not the result of changes in the cellular cation balance but is likely to be triggered by a conformational change of the protein itself. In physiological conditions, internalization may serve to eliminate pumps that have been blocked by endogenous ouabain or other cardiac glycosides. This mechanism may be required due to the very slow dissociation of the ouabain·Na(+)/K(+)-ATPase complex.
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Affiliation(s)
- Marina Cherniavsky-Lev
- From the Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot 76100, Israel
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31
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Blanco G, Wallace DP. Novel role of ouabain as a cystogenic factor in autosomal dominant polycystic kidney disease. Am J Physiol Renal Physiol 2013; 305:F797-812. [PMID: 23761677 DOI: 10.1152/ajprenal.00248.2013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The classic role of the Na-K-ATPase is that of a primary active transporter that utilizes cell energy to establish and maintain transmembrane Na(+) and K(+) gradients to preserve cell osmotic stability, support cell excitability, and drive secondary active transport. Recent studies have revealed that Na-K-ATPase located within cholesterol-containing lipid rafts serves as a receptor for cardiotonic steroids, including ouabain. Traditionally, ouabain was viewed as a toxin produced only in plants, and it was used in relatively high concentrations to experimentally block the pumping action of the Na-K-ATPase. However, the new and unexpected role of the Na-K-ATPase as a signal transducer revealed a novel facet for ouabain in the regulation of a myriad of cell functions, including cell proliferation, hypertrophy, apoptosis, mobility, and metabolism. The seminal discovery that ouabain is endogenously produced in mammals and circulates in plasma has fueled the interest in this endogenous molecule as a potentially important hormone in normal physiology and disease. In this article, we review the role of the Na-K-ATPase as an ion transporter in the kidney, the experimental evidence for ouabain as a circulating hormone, the function of the Na-K-ATPase as a signal transducer that mediates ouabain's effects, and novel results for ouabain-induced Na-K-ATPase signaling in cystogenesis of autosomal dominant polycystic kidney disease.
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Affiliation(s)
- Gustavo Blanco
- Dept. of Molecular and Integrative Physiology, 3901 Rainbow Blvd., Kansas City, KS 66160.
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32
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Cerella C, Dicato M, Diederich M. Assembling the puzzle of anti-cancer mechanisms triggered by cardiac glycosides. Mitochondrion 2013; 13:225-34. [DOI: 10.1016/j.mito.2012.06.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 06/12/2012] [Accepted: 06/19/2012] [Indexed: 02/04/2023]
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Abstract
An increasing body of clinical observations and experimental evidence suggests that cardiac dysfunction results from autonomic dysregulation of the contractile output of the heart. Excessive activation of the sympathetic nervous system and a decrease in parasympathetic tone are associated with increased mortality. Elevated levels of circulating catecholamines closely correlate with the severity and poor prognosis in heart failure. Sympathetic over-stimulation causes increased levels of catecholamines, which induce excessive aerobic metabolism leading to excessive cardiac oxygen consumption. Resulting impaired mitochondrial function causes acidosis, which results in reduction in blood flow by impairment of contractility. To the extent that the excessive aerobic metabolism resulting from adrenergic stimulation comes to a halt the energy deficit has to be compensated for by anaerobic metabolism. Glucose and glycogen become the essential nutrients. Beta-adrenergic blockade is used successfully to decrease hyperadrenergic drive. Neurohumoral antagonists block adrenergic over-stimulation but do not provide the heart with fuel for compensatory anaerobic metabolism. The endogenous hormone ouabain reduces catecholamine levels in healthy volunteers, promotes the secretion of insulin, induces release of acetylcholine from synaptosomes and potentiates the stimulation of glucose metabolism by insulin and acetylcholine. Ouabain stimulates glycogen synthesis and increases lactate utilisation by the myocardium. Decades of clinical experience with ouabain confirm the cardioprotective effects of this endogenous hormone. The so far neglected sympatholytic and vagotonic effects of ouabain on myocardial metabolism clearly make a clinical re-evaluation of this endogenous hormone necessary. Clinical studies with ouabain that correspond to current standards are warranted.
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