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Alam KA, Svalastoga P, Martinez A, Glennon JC, Haavik J. Potassium channels in behavioral brain disorders. Molecular mechanisms and therapeutic potential: A narrative review. Neurosci Biobehav Rev 2023; 152:105301. [PMID: 37414376 DOI: 10.1016/j.neubiorev.2023.105301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/26/2023] [Accepted: 06/30/2023] [Indexed: 07/08/2023]
Abstract
Potassium channels (K+-channels) selectively control the passive flow of potassium ions across biological membranes and thereby also regulate membrane excitability. Genetic variants affecting many of the human K+-channels are well known causes of Mendelian disorders within cardiology, neurology, and endocrinology. K+-channels are also primary targets of many natural toxins from poisonous organisms and drugs used within cardiology and metabolism. As genetic tools are improving and larger clinical samples are being investigated, the spectrum of clinical phenotypes implicated in K+-channels dysfunction is rapidly expanding, notably within immunology, neurosciences, and metabolism. K+-channels that previously were considered to be expressed in only a few organs and to have discrete physiological functions, have recently been found in multiple tissues and with new, unexpected functions. The pleiotropic functions and patterns of expression of K+-channels may provide additional therapeutic opportunities, along with new emerging challenges from off-target effects. Here we review the functions and therapeutic potential of K+-channels, with an emphasis on the nervous system, roles in neuropsychiatric disorders and their involvement in other organ systems and diseases.
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Affiliation(s)
| | - Pernille Svalastoga
- Mohn Center for Diabetes Precision Medicine, Department of Clinical Science, University of Bergen, Bergen, Norway; Children and Youth Clinic, Haukeland University Hospital, Bergen, Norway
| | | | - Jeffrey Colm Glennon
- Conway Institute for Biomolecular and Biomedical Research, School of Medicine, University College Dublin, Dublin, Ireland.
| | - Jan Haavik
- Department of Biomedicine, University of Bergen, Norway; Division of Psychiatry, Haukeland University Hospital, Norway.
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2
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Abbott GW. Kv Channel Ancillary Subunits: Where Do We Go from Here? Physiology (Bethesda) 2022; 37:0. [PMID: 35797055 PMCID: PMC9394777 DOI: 10.1152/physiol.00005.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/29/2022] [Accepted: 04/29/2022] [Indexed: 01/10/2023] Open
Abstract
Voltage-gated potassium (Kv) channels each comprise four pore-forming α-subunits that orchestrate essential duties such as voltage sensing and K+ selectivity and conductance. In vivo, however, Kv channels also incorporate regulatory subunits-some Kv channel specific, others more general modifiers of protein folding, trafficking, and function. Understanding all the above is essential for a complete picture of the role of Kv channels in physiology and disease.
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Affiliation(s)
- Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California
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3
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Lubberding AF, Juhl CR, Skovhøj EZ, Kanters JK, Mandrup‐Poulsen T, Torekov SS. Celebrities in the heart, strangers in the pancreatic beta cell: Voltage-gated potassium channels K v 7.1 and K v 11.1 bridge long QT syndrome with hyperinsulinaemia as well as type 2 diabetes. Acta Physiol (Oxf) 2022; 234:e13781. [PMID: 34990074 PMCID: PMC9286829 DOI: 10.1111/apha.13781] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 12/20/2021] [Accepted: 01/02/2022] [Indexed: 12/13/2022]
Abstract
Voltage‐gated potassium (Kv) channels play an important role in the repolarization of a variety of excitable tissues, including in the cardiomyocyte and the pancreatic beta cell. Recently, individuals carrying loss‐of‐function (LoF) mutations in KCNQ1, encoding Kv7.1, and KCNH2 (hERG), encoding Kv11.1, were found to exhibit post‐prandial hyperinsulinaemia and episodes of hypoglycaemia. These LoF mutations also cause the cardiac disorder long QT syndrome (LQTS), which can be aggravated by hypoglycaemia. Interestingly, patients with LQTS also have a higher burden of diabetes compared to the background population, an apparent paradox in relation to the hyperinsulinaemic phenotype, and KCNQ1 has been identified as a type 2 diabetes risk gene. This review article summarizes the involvement of delayed rectifier K+ channels in pancreatic beta cell function, with emphasis on Kv7.1 and Kv11.1, using the cardiomyocyte for context. The functional and clinical consequences of LoF mutations and polymorphisms in these channels on blood glucose homeostasis are explored using evidence from pre‐clinical, clinical and genome‐wide association studies, thereby evaluating the link between LQTS, hyperinsulinaemia and type 2 diabetes.
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Affiliation(s)
- Anniek F. Lubberding
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Christian R. Juhl
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Emil Z. Skovhøj
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Jørgen K. Kanters
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Thomas Mandrup‐Poulsen
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Signe S. Torekov
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
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4
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Sanguinetti MC, Seebohm G. Physiological Functions, Biophysical Properties, and Regulation of KCNQ1 (K V7.1) Potassium Channels. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1349:335-353. [PMID: 35138621 DOI: 10.1007/978-981-16-4254-8_15] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
KCNQ1 (KV7.1) K+ channels are expressed in multiple tissues, including the heart, pancreas, colon, and inner ear. The gene encoding the KCNQ1 protein was discovered by a positional cloning effort to determine the genetic basis of long QT syndrome, an inherited ventricular arrhythmia that can cause sudden death. Mutations in KCNQ1 can also cause other types of arrhythmia (i.e., short QT syndrome, atrial fibrillation) and the gene may also have a role in diabetes and certain cancers. KCNQ1 α-subunits can partner with accessory β-subunits (KCNE1-KCNE5) to form K+-selective channels that have divergent biophysical properties. In the heart, KCNQ1 α-subunits coassemble with KCNE1 β-subunits to form channels that conduct IKs, a very slowly activating delayed rectifier K+ current. KV7.1 channels are highly regulated by PIP2, calmodulin, and phosphorylation, and rich pharmacology includes blockers and gating modulators. Recent biophysical studies and a cryo-EM structure of the KCNQ1-calmodulin complex have provided new insights into KV7.1 channel function, and how interactions between KCNQ1 and KCNE subunits alter the gating properties of heteromultimeric channels.
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Affiliation(s)
| | - Guiscard Seebohm
- Cellular Electrophysiology and Molecular Biology, Institute for Genetics of Heart Diseases, University Hospital Münster, Münster, Germany
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5
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Abstract
Since prehistory, human species have depended on plants for both food and medicine. Even in countries with ready access to modern medicines, alternative treatments are still highly regarded and commonly used. Unlike modern pharmaceuticals, many botanical medicines are in widespread use despite a lack of safety and efficacy data derived from controlled clinical trials and often unclear mechanisms of action. Contributing to this are the complex and undefined composition and likely multifactorial mechanisms of action and multiple targets of many botanical medicines. Here, we review the newfound importance of the ubiquitous KCNQ subfamily of voltage-gated potassium channels as targets for botanical medicines, including basil, capers, cilantro, lavender, fennel, chamomile, ginger, and Camellia, Sophora, and Mallotus species. We discuss the implications for the traditional use of these plants for disorders such as seizures, hypertension, and diabetes and the molecular mechanisms of plant secondary metabolite effects on KCNQ channels.
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Affiliation(s)
- Kaitlyn E Redford
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California 92697, USA;
| | - Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California 92697, USA;
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Effects of Dapagliflozin Adjunct to Insulin on Glycemic Variations in Patients with Newly Diagnosed Type 2 Diabetes: A Randomized, Controlled, Open-Labeled Trial. BIOMED RESEARCH INTERNATIONAL 2021; 2021:6618257. [PMID: 34497852 PMCID: PMC8419509 DOI: 10.1155/2021/6618257] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 08/10/2021] [Indexed: 01/10/2023]
Abstract
Background This study is aimed at investigating whether dapagliflozin adjunct to insulin therapy further improves glycemic control compared to insulin therapy alone in patients with newly diagnosed type 2 diabetes (T2D). Methods This single-centre, randomized, controlled, open-labeled trial recruited newly diagnosed T2D patients. Subjects were randomized 1 : 1 to the dapagliflozin add-on to continuous subcutaneous insulin infusion (CSII) group (DAPA) or the CSII therapy group for 5 weeks. Standard meal tests were performed 3 times at days -3, 7, and 35 for glucose, C-peptide, and insulin level determination. Two-time continuous glucose monitoring (CGM) was performed at baseline and at the end of the study. The primary endpoint was the difference in the mean amplitude of glycemic excursions (MAGEs) between the groups. Results A total of 66 subjects completed the study, with 34 and 32 patients in the DAPA and CSII groups, respectively. Patients in the DAPA group exhibited significant decreases in MAGE levels at the endpoint. We also observed that patients in the DAPA group had a lower homoeostasis model assessment insulin resistance (HOMA-IR) and a higher homoeostasis model assessment B (HOMA-B) value at 1 week and 5 weeks compared to those with insulin therapy, respectively. In addition, our data showed that patients in the DAPA group showed a significantly lower insulin dose (0.07 U/kg) and weighed less than those in the CSII group. Conclusion Our data indicate that dapagliflozin adjunct to insulin is a safe and effective therapy for improving glycemic variations, insulin sensitivity, and weight loss in newly diagnosed T2D patients.
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Fluorescence Fluctuation Spectroscopy enables quantification of potassium channel subunit dynamics and stoichiometry. Sci Rep 2021; 11:10719. [PMID: 34021177 PMCID: PMC8140153 DOI: 10.1038/s41598-021-90002-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 04/15/2021] [Indexed: 11/08/2022] Open
Abstract
Voltage-gated potassium (Kv) channels are a family of membrane proteins that facilitate K+ ion diffusion across the plasma membrane, regulating both resting and action potentials. Kv channels comprise four pore-forming α subunits, each with a voltage sensing domain, and they are regulated by interaction with β subunits such as those belonging to the KCNE family. Here we conducted a comprehensive biophysical characterization of stoichiometry and protein diffusion across the plasma membrane of the epithelial KCNQ1-KCNE2 complex, combining total internal reflection fluorescence (TIRF) microscopy and a series of complementary Fluorescence Fluctuation Spectroscopy (FFS) techniques. Using this approach, we found that KCNQ1-KCNE2 has a predominant 4:4 stoichiometry, while non-bound KCNE2 subunits are mostly present as dimers in the plasma membrane. At the same time, we identified unique spatio-temporal diffusion modalities and nano-environment organization for each channel subunit. These findings improve our understanding of KCNQ1-KCNE2 channel function and suggest strategies for elucidating the subunit stoichiometry and forces directing localization and diffusion of ion channel complexes in general.
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Prashanth G, Vastrad B, Tengli A, Vastrad C, Kotturshetti I. Investigation of candidate genes and mechanisms underlying obesity associated type 2 diabetes mellitus using bioinformatics analysis and screening of small drug molecules. BMC Endocr Disord 2021; 21:80. [PMID: 33902539 PMCID: PMC8074411 DOI: 10.1186/s12902-021-00718-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 03/02/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Obesity associated type 2 diabetes mellitus is a metabolic disorder ; however, the etiology of obesity associated type 2 diabetes mellitus remains largely unknown. There is an urgent need to further broaden the understanding of the molecular mechanism associated in obesity associated type 2 diabetes mellitus. METHODS To screen the differentially expressed genes (DEGs) that might play essential roles in obesity associated type 2 diabetes mellitus, the publicly available expression profiling by high throughput sequencing data (GSE143319) was downloaded and screened for DEGs. Then, Gene Ontology (GO) and REACTOME pathway enrichment analysis were performed. The protein - protein interaction network, miRNA - target genes regulatory network and TF-target gene regulatory network were constructed and analyzed for identification of hub and target genes. The hub genes were validated by receiver operating characteristic (ROC) curve analysis and RT- PCR analysis. Finally, a molecular docking study was performed on over expressed proteins to predict the target small drug molecules. RESULTS A total of 820 DEGs were identified between healthy obese and metabolically unhealthy obese, among 409 up regulated and 411 down regulated genes. The GO enrichment analysis results showed that these DEGs were significantly enriched in ion transmembrane transport, intrinsic component of plasma membrane, transferase activity, transferring phosphorus-containing groups, cell adhesion, integral component of plasma membrane and signaling receptor binding, whereas, the REACTOME pathway enrichment analysis results showed that these DEGs were significantly enriched in integration of energy metabolism and extracellular matrix organization. The hub genes CEBPD, TP73, ESR2, TAB1, MAP 3K5, FN1, UBD, RUNX1, PIK3R2 and TNF, which might play an essential role in obesity associated type 2 diabetes mellitus was further screened. CONCLUSIONS The present study could deepen the understanding of the molecular mechanism of obesity associated type 2 diabetes mellitus, which could be useful in developing therapeutic targets for obesity associated type 2 diabetes mellitus.
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Affiliation(s)
- G Prashanth
- Department of General Medicine, Basaveshwara Medical College, Chitradurga, Karnataka, 577501, India
| | - Basavaraj Vastrad
- Department of Biochemistry, Basaveshwar College of Pharmacy, Gadag, Karnataka, 582103, India
| | - Anandkumar Tengli
- Department of Pharmaceutical Chemistry, JSS College of Pharmacy, Mysuru and JSS Academy of Higher Education & Research, Mysuru, Karnataka, 570015, India
| | - Chanabasayya Vastrad
- Biostatistics and Bioinformatics, Chanabasava Nilaya, Bharthinagar, Dharwad, Karnataka, 580001, India.
| | - Iranna Kotturshetti
- Department of Ayurveda, Rajiv Gandhi Education Society`s Ayurvedic Medical College, Ron, Karnataka, 582209, India
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9
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Papanikolaou M, Crump SM, Abbott GW. The focal adhesion protein Testin modulates KCNE2 potassium channel β subunit activity. Channels (Austin) 2021; 15:229-238. [PMID: 33464998 PMCID: PMC7833772 DOI: 10.1080/19336950.2021.1874119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Coronary Artery Disease (CAD) typically kills more people globally each year than any other single cause of death. A better understanding of genetic predisposition to CAD and the underlying mechanisms will help to identify those most at risk and contribute to improved therapeutic approaches. KCNE2 is a functionally versatile, ubiquitously expressed potassium channel β subunit associated with CAD and cardiac arrhythmia susceptibility in humans and mice. Here, to identify novel KCNE2 interaction partners, we employed yeast two-hybrid screening of adult and fetal human heart libraries using the KCNE2 intracellular C-terminal domain as bait. Testin (encoded by TES), an endothelial cell-expressed, CAD-associated, focal adhesion protein, was identified as a high-confidence interaction partner for KCNE2. We confirmed physical association between KCNE2 and Testin in vitro by co-immunoprecipitation. Whole-cell patch clamp electrophysiology revealed that KCNE2 negative-shifts the voltage dependence and increases the rate of activation of the endothelial cell and cardiomyocyte-expressed Kv channel α subunit, Kv1.5 in CHO cells, whereas Testin did not alter Kv1.5 function. However, Testin nullified KCNE2 effects on Kv1.5 voltage dependence and gating kinetics. In contrast, Testin did not prevent KCNE2 regulation of KCNQ1 gating. The data identify a novel role for Testin as a tertiary ion channel regulatory protein. Future studies will address the potential role for KCNE2-Testin interactions in arterial and myocyte physiology and CAD.
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Affiliation(s)
- Maria Papanikolaou
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California , Irvine, CA, USA
| | - Shawn M Crump
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California , Irvine, CA, USA
| | - Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California , Irvine, CA, USA
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10
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Ho-Plagaro A, Santiago-Fernandez C, Rodríguez-Díaz C, Lopez-Gómez C, Garcia-Serrano S, Rodríguez-Pacheco F, Valdes S, Rodríguez-Cañete A, Alcaín-Martínez G, Ruiz-Santana N, Vázquez-Pedreño L, García-Fuentes E. Different Expression of Duodenal Genes Related to Insulin Resistance Between Nonobese Women and Those with Severe Obesity. Obesity (Silver Spring) 2020; 28:1708-1717. [PMID: 32729246 DOI: 10.1002/oby.22902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 04/14/2020] [Accepted: 05/07/2020] [Indexed: 12/26/2022]
Abstract
OBJECTIVE The study aim was to identify changes in duodenal gene expression associated with the development of insulin resistance according to the BMI of women. METHODS Duodenal samples were assessed by microarray in four groups of women, nonobese women and women with severe obesity, with both low and high insulin resistance. RESULTS There was a group of shared downregulated differentially expressed genes (DEGs) related to tissue homeostasis and antimicrobial humoral response in women with higher insulin resistance both with severe obesity and without obesity. In the exclusive DEGs found in severe obesity, downregulated DEGs related to the regulation of the defense response to bacterium and cell adhesion, involving pathways related to the immune system, inflammation, and xenobiotic metabolism, were observed. In the exclusive DEGs from nonobese women with higher insulin resistance, upregulated DEGs mainly related to the regulation of lipoprotein lipase activity, very low-density lipoprotein particle remodeling, lipid metabolic process, antigen processing, and the presentation of peptide antigen were found. CONCLUSIONS Independent of BMI, higher insulin resistance was associated with a downregulation of duodenal DEGs mainly related to the immune system, inflammation, and xenobiotic metabolism. Also, intestinal lipoprotein metabolism may have a certain relevance in the regulation of insulin resistance in nonobese women.
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Affiliation(s)
- Ailec Ho-Plagaro
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
- Unidad de Gestión Clínica de Aparato Digestivo, Hospital Universitario Virgen de la Victoria, Málaga, Spain
- Departamento de Biología Celular, Genética y Fisiología, Universidad de Málaga, Málaga, Spain
| | - Concepción Santiago-Fernandez
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
- Unidad de Gestión Clínica de Aparato Digestivo, Hospital Universitario Virgen de la Victoria, Málaga, Spain
- Departamento de Medicina y Dermatología, Universidad de Málaga, Málaga, Spain
| | - Cristina Rodríguez-Díaz
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
- Unidad de Gestión Clínica de Aparato Digestivo, Hospital Universitario Virgen de la Victoria, Málaga, Spain
| | - Carlos Lopez-Gómez
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
- Unidad de Gestión Clínica de Aparato Digestivo, Hospital Universitario Virgen de la Victoria, Málaga, Spain
| | - Sara Garcia-Serrano
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
- Unidad de Gestión Clínica de Endocrinología y Nutrición, Hospital Regional Universitario de Málaga, Málaga, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas-CIBERDEM, Málaga, Spain
| | - Francisca Rodríguez-Pacheco
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
- Unidad de Gestión Clínica de Aparato Digestivo, Hospital Universitario Virgen de la Victoria, Málaga, Spain
| | - Sergio Valdes
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
- Unidad de Gestión Clínica de Endocrinología y Nutrición, Hospital Regional Universitario de Málaga, Málaga, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas-CIBERDEM, Málaga, Spain
| | - Alberto Rodríguez-Cañete
- Unidad de Gestión Clínica de Cirugía General, Digestiva y Trasplantes, Hospital Regional Universitario de Málaga, Málaga, Spain
| | - Guillermo Alcaín-Martínez
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
- Unidad de Gestión Clínica de Aparato Digestivo, Hospital Universitario Virgen de la Victoria, Málaga, Spain
| | - Natalia Ruiz-Santana
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
- Unidad de Gestión Clínica de Aparato Digestivo, Hospital Universitario Virgen de la Victoria, Málaga, Spain
| | - Luis Vázquez-Pedreño
- Unidad de Gestión Clínica de Aparato Digestivo, Hospital Regional Universitario de Málaga, Málaga, Spain
| | - Eduardo García-Fuentes
- Instituto de Investigación Biomédica de Málaga-IBIMA, Málaga, Spain
- Unidad de Gestión Clínica de Aparato Digestivo, Hospital Universitario Virgen de la Victoria, Málaga, Spain
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van der Horst J, Greenwood IA, Jepps TA. Cyclic AMP-Dependent Regulation of Kv7 Voltage-Gated Potassium Channels. Front Physiol 2020; 11:727. [PMID: 32695022 PMCID: PMC7338754 DOI: 10.3389/fphys.2020.00727] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 06/04/2020] [Indexed: 01/08/2023] Open
Abstract
Voltage-gated Kv7 potassium channels, encoded by KCNQ genes, have major physiological impacts cardiac myocytes, neurons, epithelial cells, and smooth muscle cells. Cyclic adenosine monophosphate (cAMP), a well-known intracellular secondary messenger, can activate numerous downstream effector proteins, generating downstream signaling pathways that regulate many functions in cells. A role for cAMP in ion channel regulation has been established, and recent findings show that cAMP signaling plays a role in Kv7 channel regulation. Although cAMP signaling is recognized to regulate Kv7 channels, the precise molecular mechanism behind the cAMP-dependent regulation of Kv7 channels is complex. This review will summarize recent research findings that support the mechanisms of cAMP-dependent regulation of Kv7 channels.
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Affiliation(s)
- Jennifer van der Horst
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Iain A Greenwood
- Molecular and Clinical Sciences Institute, St. George's University of London, London, United Kingdom
| | - Thomas A Jepps
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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12
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Lisewski U, Köhncke C, Schleussner L, Purfürst B, Lee SM, De Silva A, Manville RW, Abbott GW, Roepke TK. Hypochlorhydria reduces mortality in heart failure caused by Kcne2 gene deletion. FASEB J 2020; 34:10699-10719. [PMID: 32584506 DOI: 10.1096/fj.202000013rr] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 05/20/2020] [Accepted: 06/02/2020] [Indexed: 12/23/2022]
Abstract
Heart failure (HF) is an increasing global health crisis, affecting 40 million people and causing 50% mortality within 5 years of diagnosis. A fuller understanding of the genetic and environmental factors underlying HF, and novel therapeutic approaches to address it, are urgently warranted. Here, we discovered that cardiac-specific germline deletion in mice of potassium channel β subunit-encoding Kcne2 (Kcne2CS-/- ) causes dilated cardiomyopathy and terminal HF (median longevity, 28 weeks). Mice with global Kcne2 deletion (Kcne2Glo-/- ) exhibit multiple HF risk factors, yet, paradoxically survived over twice as long as Kcne2CS-/- mice. Global Kcne2 deletion, which inhibits gastric acid secretion, reduced the relative abundance of species within Bacteroidales, a bacterial order that positively correlates with increased lifetime risk of human cardiovascular disease. Strikingly, the proton-pump inhibitor omeprazole similarly altered the microbiome and delayed terminal HF in Kcne2CS-/- mice, increasing survival 10-fold at 44 weeks. Thus, genetic or pharmacologic induction of hypochlorhydria and decreased gut Bacteroidales species are associated with lifespan extension in a novel HF model.
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Affiliation(s)
| | - Clemens Köhncke
- Experimental and Clinical Research Center, Berlin, Germany.,Department of Cardiology, Campus Virchow - Universitätsmedizin Berlin, Berlin, Germany
| | | | - Bettina Purfürst
- Electron Microscopy Core Facility, Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | - Soo Min Lee
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA
| | - Angele De Silva
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA
| | - Rían W Manville
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA
| | - Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA
| | - Torsten K Roepke
- Experimental and Clinical Research Center, Berlin, Germany.,Department of Cardiology and Angiology, Campus Mitte, Charité - Universitätsmedizin Berlin, Berlin, Germany
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13
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Hu Z, Liu J, Zhou L, Tian X, Abbott GW. AKT and ERK1/2 activation via remote ischemic preconditioning prevents Kcne2-dependent sudden cardiac death. Physiol Rep 2020; 7:e13957. [PMID: 30737904 PMCID: PMC6368489 DOI: 10.14814/phy2.13957] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 11/26/2018] [Indexed: 02/05/2023] Open
Abstract
Sudden cardiac death (SCD) is the leading global cause of mortality. SCD often arises from cardiac ischemia reperfusion (IR) injury, pathologic sequence variants within ion channel genes, or a combination of the two. Alternative approaches are needed to prevent or ameliorate ventricular arrhythmias linked to SCD. Here, we investigated the efficacy of remote ischemic preconditioning (RIPC) of the limb versus the liver in reducing ventricular arrhythmias in a mouse model of SCD. Mice lacking the Kcne2 gene, which encodes a potassium channel β subunit associated with acquired Long QT syndrome were exposed to IR injury via coronary ligation. This resulted in ventricular arrhythmias in all mice (15/15) and SCD in 5/15 mice during reperfusion. Strikingly, prior RIPC (limb or liver) greatly reduced the incidence and severity of all ventricular arrhythmias and completely prevented SCD. Biochemical and pharmacological analysis demonstrated that RIPC cardioprotection required ERK1/2 and/or AKT phosphorylation. A lack of alteration in GSK‐3β phosphorylation suggested against conventional reperfusion injury salvage kinase (RISK) signaling pathway protection. If replicated in human studies, limb RIPC could represent a noninvasive, nonpharmacological approach to limit dangerous ventricular arrhythmias associated with ischemia and/or channelopathy‐linked SCD.
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Affiliation(s)
- Zhaoyang Hu
- Laboratory of Anesthesiology & Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jin Liu
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Leng Zhou
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xin Tian
- Laboratory of Anesthesiology & Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California
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14
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Shi Y, Yan C, Li Y, Zhang Y, Zhang G, Li M, Li B, Zhao X. Expression signature of miRNAs and the potential role of miR-195-5p in high-glucose-treated rat cardiomyocytes. J Biochem Mol Toxicol 2019; 34:e22423. [PMID: 31729781 DOI: 10.1002/jbt.22423] [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] [Received: 04/13/2019] [Revised: 10/10/2019] [Accepted: 10/30/2019] [Indexed: 12/12/2022]
Abstract
MicroRNAs are endogenous small noncoding RNAs that posttranscriptionally regulate the expression of target genes and play crucial roles in diverse physiopathologic processes. In the current study, we examined the microRNA (miRNA) expression profile of high-glucose-treated neonatal rat cardiomyocytes and the potential mechanisms. Differentially expressed miRNAs were analyzed by a miRNA microarray and validated by a quantitative real-time polymerase chain reaction in high-glucose-treated rat cardiomyocytes. Based on the results of our previous study and the bioinformatics prediction, we identified miR-195-5p/SGK1/Nedd4-2/hERG as the top-ranked signal pathway in diabetes cell model in vitro. In summary, our present study provides novel insights into the regulatory mechanism of miR-195-5p/SGK1/Nedd4-2/hERG in rat cardiomyocytes under high-glucose stress, which may provide a novel idea for the development of diagnostic and therapeutic strategies for diabetic cardiomyopathy in the future.
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Affiliation(s)
- Yuanqi Shi
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Caichuan Yan
- Department of Pharmacology, College of Pharmacy, Harbin Medical University, Harbin, China.,Department of Cancer Molecular and Biology, Heilongjiang Academy of Medical Sciences, Harbin Medical University, Harbin, China
| | - Yang Li
- Department of Pharmacology, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Yuhao Zhang
- Department of Pharmacology, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Guocui Zhang
- Department of Pharmacology, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Mingzhu Li
- Department of Pharmacology, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Baoxin Li
- Department of Pharmacology, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Xin Zhao
- Department of Pharmacology, College of Pharmacy, Harbin Medical University, Harbin, China
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15
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Liu X, Li Y, Zhang H, Ji Y, Zhao Z, Wang C. The research of ion channel-related gene polymorphisms with atrial fibrillation in the Chinese Han population. Mol Genet Genomic Med 2019; 7:e835. [PMID: 31270966 PMCID: PMC6687643 DOI: 10.1002/mgg3.835] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 05/20/2019] [Accepted: 06/10/2019] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Atrial fibrillation (AF) is one of the common arrhythmia in clinics. Its incidence is high among the elderly. This study aimed to identify a possible connection between ion channel-related gene polymorphisms and the risk of AF. METHODS A total of 381 patients with coronary heart disease were recruited. Based on complete cardiac examination, the patients were divided into two subgroups: 185 patients with AF and 196 patients without AF. An association analysis was performed using 13 genotyped SNPs. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated by conditional logistic regression. RESULTS In our research, we found that KCNE2 rs8134775 was associated with a decreased AF risk in the allele model (OR = 0.70; 95% CI: 0.50-0.97; p = 0.034). Genetic model analysis shown that the minor allele T of GJA5 rs35594137 was associated with a decreased AF risk under the recessive model (OR = 0.40; 95% CI: 0.19-0.86; p = 0.018) and the minor allele G of KCNJ2 rs8079702 was associated with an increased AF risk in the recessive model (OR = 2.31; 95% CI: 1.20-4.42; p = 0.012). CONCLUSIONS Our results suggest that KCNE2, KCNJ2, and GJA5 influence the development of AF.
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Affiliation(s)
- Xiumin Liu
- Department of Cardiovascular Medicinethe Affiliated Hospital of Northwest University & Xi’an No.3 HospitalXi’anShaanxiChina
| | - Yujie Li
- Department of Cardiovascular MedicineFirst hospital of Xi’anXi’anShaanxiChina
| | - Huan Zhang
- Department of Cardiovascular Medicinethe Affiliated Hospital of Northwest University & Xi’an No.3 HospitalXi’anShaanxiChina
| | - Yuqiang Ji
- Department of Cardiovascular MedicineFirst hospital of Xi’anXi’anShaanxiChina
| | - Zhao Zhao
- Department of Cardiovascular MedicineFirst Affiliated Hospital of Xi'an Jiaotong UniversityXi’anShaanxiChina
| | - Changyu Wang
- Department of Cardiovascular Medicinethe Affiliated Hospital of Northwest University & Xi’an No.3 HospitalXi’anShaanxiChina
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16
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Dapagliflozin rescues endoplasmic reticulum stress-mediated cell death. Sci Rep 2019; 9:9887. [PMID: 31285506 PMCID: PMC6614429 DOI: 10.1038/s41598-019-46402-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 06/26/2019] [Indexed: 01/14/2023] Open
Abstract
The new type 2 diabetes drug, dapagliflozin, reduces blood glucose levels and body weight by inhibiting sodium glucose transporter 2 (SGLT2) in proximal tubular cells. SGLT2 inhibitors might modulate glucose influx into renal tubular cells, thereby regulating the metabolic conditions that cause endoplasmic reticulum (ER) stress in the cells. In this study, we examined the effect of dapagliflozin on ER stress in the HK-2 proximal tubular cell line and in the kidney of db/db mice to characterise its function in diabetic nephropathy (DN). We found that dapagliflozin regulated ER stress-mediated apoptosis in vitro and in vivo. Only the elf2α-ATF4-CHOP pathway was regulated under these conditions. Notably, the drug rescued C2 ceramide-induced ER stress-mediated apoptosis and ER stress-mediated apoptosis, which might occur in DN, in db/db mice. Our study shows a novel role for dapagliflozin as an inhibitor of ER stress and suggests that dapagliflozin might be useful for the prevention of DN.
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17
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Zhou L, Köhncke C, Hu Z, Roepke TK, Abbott GW. The KCNE2 potassium channel β subunit is required for normal lung function and resilience to ischemia and reperfusion injury. FASEB J 2019; 33:9762-9774. [PMID: 31162977 DOI: 10.1096/fj.201802519r] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The KCNE2 single transmembrane-spanning voltage-gated potassium (Kv) channel β subunit is ubiquitously expressed and essential for normal function of a variety of cell types, often via regulation of the KCNQ1 Kv channel. A polymorphism upstream of KCNE2 is associated with reduced lung function in human populations, but the pulmonary consequences of KCNE2 gene disruption are unknown. Here, germline deletion of mouse Kcne2 reduced pulmonary expression of potassium channel α subunits Kcnq1 and Kcnb1 but did not alter expression of other Kcne genes. Kcne2 colocalized and coimmunoprecipitated with Kcnq1 in mouse lungs, suggesting the formation of pulmonary Kcnq1-Kcne2 potassium channel complexes. Kcne2 deletion reduced blood O2, increased CO2, increased pulmonary apoptosis, and increased inflammatory mediators TNF-α, IL-6, and leukocytes in bronchoalveolar lavage (BAL) fluids. Consistent with increased pulmonary vascular leakage, Kcne2 deletion increased plasma, BAL albumin, and the BAL:plasma albumin concentration ratio. Kcne2-/- mouse lungs exhibited baseline induction of the reperfusion injury salvage kinase pathway but were less able to respond via this pathway to imposed pulmonary ischemia/reperfusion injury (IRI). We conclude that KCNE2 regulates KCNQ1 in the lungs and is required for normal lung function and resistance to pulmonary IRI. Our data support a causal relationship between KCNE2 gene disruption and lung dysfunction.-Zhou, L., Köhncke, C., Hu, Z., Roepke, T. K., Abbott, G. W. The KCNE2 potassium channel β subunit is required for normal lung function and resilience to ischemia and reperfusion injury.
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Affiliation(s)
- Leng Zhou
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, China
| | - Clemens Köhncke
- Experimental and Clinical Research Center, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Zhaoyang Hu
- Laboratory of Anesthesiology and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, China
| | - Torsten K Roepke
- Experimental and Clinical Research Center, Max Delbrück Center for Molecular Medicine, Berlin, Germany.,Clinic for Cardiology and Angiology, Charité-Berlin University of Medicine Campus Mitte, Berlin, Germany.,Clinic for Internal Medicine and Cardiology Klinikum Niederlausitz, Senftenberg, Germany
| | - Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California-Irvine, Irvine, California, USA
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18
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Platania CBM, Leggio GM, Drago F, Salomone S, Bucolo C. Computational systems biology approach to identify novel pharmacological targets for diabetic retinopathy. Biochem Pharmacol 2018; 158:13-26. [DOI: 10.1016/j.bcp.2018.09.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 09/13/2018] [Indexed: 12/11/2022]
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19
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David JP, Lisewski U, Crump SM, Jepps TA, Bocksteins E, Wilck N, Lossie J, Roepke TK, Schmitt N, Abbott GW. Deletion in mice of X-linked, Brugada syndrome- and atrial fibrillation-associated Kcne5 augments ventricular K V currents and predisposes to ventricular arrhythmia. FASEB J 2018; 33:2537-2552. [PMID: 30289750 DOI: 10.1096/fj.201800502r] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
KCNE5 is an X-linked gene encoding KCNE5, an ancillary subunit to voltage-gated potassium (KV) channels. Human KCNE5 mutations are associated with atrial fibrillation (AF)- and Brugada syndrome (BrS)-induced cardiac arrhythmias that can arise from increased potassium current in cardiomyocytes. Seeking to establish underlying molecular mechanisms, we created and studied Kcne5 knockout ( Kcne5-/0) mice. Intracardiac ECG revealed that Kcne5 deletion caused ventricular premature beats, increased susceptibility to induction of polymorphic ventricular tachycardia (60 vs. 24% in Kcne5+/0 mice), and 10% shorter ventricular refractory period. Kcne5 deletion increased mean ventricular myocyte KV current density in the apex and also in the subpopulation of septal myocytes that lack fast transient outward current ( Ito,f). The current increases arose from an apex-specific increase in slow transient outward current-1 ( IKslow,1) (conducted by KV1.5) and Ito,f (conducted by KV4) and an increase in IKslow,2 (conducted by KV2.1) in both apex and septum. Kcne5 protein localized to the intercalated discs in ventricular myocytes, where KV2.1 was also detected in both Kcne5-/0 and Kcne5+/0 mice. In HL-1 cardiac cells and human embryonic kidney cells, KCNE5 and KV2.1 colocalized at the cell surface, but predominantly in intracellular vesicles, suggesting that Kcne5 deletion increases IK,slow2 by reducing KV2.1 intracellular sequestration. The human AF-associated mutation KCNE5-L65F negative shifted the voltage dependence of KV2.1-KCNE5 channels, increasing their maximum current density >2-fold, whereas BrS-associated KCNE5 mutations produced more subtle negative shifts in KV2.1 voltage dependence. The findings represent the first reported native role for Kcne5 and the first demonstrated Kcne regulation of KV2.1 in mouse heart. Increased KV current is a manifestation of KCNE5 disruption that is most likely common to both mouse and human hearts, providing a plausible mechanistic basis for human KCNE5-linked AF and BrS.-David, J.-P., Lisewski, U., Crump, S. M., Jepps, T. A., Bocksteins, E., Wilck, N., Lossie, J., Roepke, T. K., Schmitt, N., Abbott, G. W. Deletion in mice of X-linked, Brugada syndrome- and atrial fibrillation-associated Kcne5 augments ventricular KV currents and predisposes to ventricular arrhythmia.
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Affiliation(s)
- Jens-Peter David
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ulrike Lisewski
- Medical Clinic and Polyclinic for Cardiology and Angiology, Charité Medical University of Berlin, Berlin, Germany.,Experimental and Clinical Research Center (ECRC), Charité Medical University of Berlin, Berlin, Germany
| | - Shawn M Crump
- Bioelectricity Laboratory, Department of Physiology and Biophysics, University of California, Irvine, Irvine, California, USA; and
| | - Thomas A Jepps
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Elke Bocksteins
- Laboratory for Molecular Biophysics, Physiology, and Pharmacology, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Nicola Wilck
- Medical Clinic and Polyclinic for Cardiology and Angiology, Charité Medical University of Berlin, Berlin, Germany.,Experimental and Clinical Research Center (ECRC), Charité Medical University of Berlin, Berlin, Germany
| | - Janine Lossie
- Medical Clinic and Polyclinic for Cardiology and Angiology, Charité Medical University of Berlin, Berlin, Germany.,Experimental and Clinical Research Center (ECRC), Charité Medical University of Berlin, Berlin, Germany
| | - Torsten K Roepke
- Medical Clinic and Polyclinic for Cardiology and Angiology, Charité Medical University of Berlin, Berlin, Germany.,Experimental and Clinical Research Center (ECRC), Charité Medical University of Berlin, Berlin, Germany
| | - Nicole Schmitt
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, University of California, Irvine, Irvine, California, USA; and
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20
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Huttunen H, Hero M, Lääperi M, Känsäkoski J, Swan H, Hirsch JA, Miettinen PJ, Raivio T. The Role of KCNQ1 Mutations and Maternal Beta Blocker Use During Pregnancy in the Growth of Children With Long QT Syndrome. Front Endocrinol (Lausanne) 2018; 9:194. [PMID: 29740400 PMCID: PMC5928157 DOI: 10.3389/fendo.2018.00194] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 04/09/2018] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE Two missense mutations in KCNQ1, an imprinted gene that encodes the alpha subunit of the voltage-gated potassium channel Kv7.1, cause autosomal dominant growth hormone deficiency and maternally inherited gingival fibromatosis. We evaluated endocrine features, birth size, and subsequent somatic growth of patients with long QT syndrome 1 (LQT1) due to loss-of-function mutations in KCNQ1. DESIGN Medical records of 104 patients with LQT1 in a single tertiary care center between 1995 and 2015 were retrospectively reviewed. METHODS Clinical and endocrine data of the LQT1 patients were included in the analyses. RESULTS At birth, patients with a maternally inherited mutation (n = 52) were shorter than those with paternal inheritance of the mutation (n = 29) (birth length, -0.70 ± 1.1 SDS vs. -0.2 ± 1.0 SDS, P < 0.05). Further analyses showed, however, that only newborns (n = 19) of mothers who had received beta blockers during pregnancy were shorter and lighter at birth than those with paternal inheritance of the mutation (n = 29) (-0.89 ± 1.0 SDS vs. -0.20 ± 1.0 SDS, P < 0.05; and 3,173 ± 469 vs. 3,515 ± 466 g, P < 0.05). Maternal beta blocker treatment during the pregnancy was also associated with lower cord blood TSH levels (P = 0.011) and significant catch-up growth during the first year of life (Δ0.08 SDS/month, P = 0.004). Later, childhood growth of the patients was unremarkable. CONCLUSION Loss-of-function mutations in KCNQ1 are not associated with abnormalities in growth, whereas maternal beta blocker use during pregnancy seems to modify prenatal growth of LQT1 patients-a phenomenon followed by catch-up growth after birth.
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Affiliation(s)
- Heta Huttunen
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Matti Hero
- Children’s Hospital, Pediatric Research Center, University of Helsinki, Helsinki University Hospital, Helsinki, Finland
| | - Mitja Lääperi
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Johanna Känsäkoski
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Heikki Swan
- Heart and Lung Center, Helsinki University Hospital, Helsinki, Finland
| | - Joel A. Hirsch
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Institute of Structural Biology, Tel Aviv University, Ramat Aviv, Israel
| | - Päivi J. Miettinen
- Children’s Hospital, Pediatric Research Center, University of Helsinki, Helsinki University Hospital, Helsinki, Finland
| | - Taneli Raivio
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- Children’s Hospital, Pediatric Research Center, University of Helsinki, Helsinki University Hospital, Helsinki, Finland
- *Correspondence: Taneli Raivio,
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21
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Tommiska J, Känsäkoski J, Skibsbye L, Vaaralahti K, Liu X, Lodge EJ, Tang C, Yuan L, Fagerholm R, Kanters JK, Lahermo P, Kaunisto M, Keski-Filppula R, Vuoristo S, Pulli K, Ebeling T, Valanne L, Sankila EM, Kivirikko S, Lääperi M, Casoni F, Giacobini P, Phan-Hug F, Buki T, Tena-Sempere M, Pitteloud N, Veijola R, Lipsanen-Nyman M, Kaunisto K, Mollard P, Andoniadou CL, Hirsch JA, Varjosalo M, Jespersen T, Raivio T. Two missense mutations in KCNQ1 cause pituitary hormone deficiency and maternally inherited gingival fibromatosis. Nat Commun 2017; 8:1289. [PMID: 29097701 PMCID: PMC5668380 DOI: 10.1038/s41467-017-01429-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 09/14/2017] [Indexed: 01/05/2023] Open
Abstract
Familial growth hormone deficiency provides an opportunity to identify new genetic causes of short stature. Here we combine linkage analysis with whole-genome resequencing in patients with growth hormone deficiency and maternally inherited gingival fibromatosis. We report that patients from three unrelated families harbor either of two missense mutations, c.347G>T p.(Arg116Leu) or c.1106C>T p.(Pro369Leu), in KCNQ1, a gene previously implicated in the long QT interval syndrome. Kcnq1 is expressed in hypothalamic GHRH neurons and pituitary somatotropes. Co-expressing KCNQ1 with the KCNE2 β-subunit shows that both KCNQ1 mutants increase current levels in patch clamp analyses and are associated with reduced pituitary hormone secretion from AtT-20 cells. In conclusion, our results reveal a role for the KCNQ1 potassium channel in the regulation of human growth, and show that growth hormone deficiency associated with maternally inherited gingival fibromatosis is an allelic disorder with cardiac arrhythmia syndromes caused by KCNQ1 mutations.
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Affiliation(s)
- Johanna Tommiska
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland.,Children's Hospital, Pediatric Research Center, Helsinki University Central Hospital (HUCH), 00029, Helsinki, Finland
| | - Johanna Känsäkoski
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland
| | - Lasse Skibsbye
- Department of Biomedical Sciences, University of Copenhagen, 2200, Copenhagen N, Denmark
| | - Kirsi Vaaralahti
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland
| | - Xiaonan Liu
- Institute of Biotechnology, Biocenter 3, University of Helsinki, 00014, Helsinki, Finland
| | - Emily J Lodge
- Centre for Craniofacial and Regenerative Biology, King's College London, Floor 27 Tower Wing, Guy's Campus, London, SE1 9RT, UK
| | - Chuyi Tang
- Department of Biomedical Sciences, University of Copenhagen, 2200, Copenhagen N, Denmark
| | - Lei Yuan
- Department of Biomedical Sciences, University of Copenhagen, 2200, Copenhagen N, Denmark
| | - Rainer Fagerholm
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland.,Department of Obstetrics and Gynecology, HUCH, 00029, Helsinki, Finland
| | - Jørgen K Kanters
- Laboratory of Experimental Cardiology, Department of Biomedical Sciences, University of Copenhagen, 22000, Copenhagen, Denmark.,Department of Cardiology, Herlev & Gentofte University Hospitals, University of Copenhagen, 22000, Copenhagen, Denmark
| | - Päivi Lahermo
- Institute for Molecular Medicine Finland (FIMM), Helsinki Institute of Life Science HiLIFE, University of Helsinki, 00014, Helsinki, Finland
| | - Mari Kaunisto
- Institute for Molecular Medicine Finland (FIMM), Helsinki Institute of Life Science HiLIFE, University of Helsinki, 00014, Helsinki, Finland
| | | | - Sanna Vuoristo
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland
| | - Kristiina Pulli
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland
| | - Tapani Ebeling
- Department of Medicine, Oulu University Hospital, Finland and Research Unit of Internal Medicine, University of Oulu, 90014, Oulu, Finland
| | - Leena Valanne
- Helsinki Medical Imaging Center, HUCH, 00029, Helsinki, Finland
| | | | - Sirpa Kivirikko
- Department of Clinical Genetics, HUCH, 00029, Helsinki, Finland
| | - Mitja Lääperi
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland
| | - Filippo Casoni
- Inserm U1172, Jean-Pierre Aubert Research Center, Development and Plasticity of the Neuroendocrine Brain, 59045, Lille, France.,University of Lille, School of Medicine, 59045, Lille, France
| | - Paolo Giacobini
- Inserm U1172, Jean-Pierre Aubert Research Center, Development and Plasticity of the Neuroendocrine Brain, 59045, Lille, France.,University of Lille, School of Medicine, 59045, Lille, France
| | - Franziska Phan-Hug
- Pediatrics, Division of Pediatric Endocrinology, Diabetology and Obesity, University Hospital Lausanne (CHUV), 1011, Lausanne, Switzerland
| | - Tal Buki
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Institute of Structural Biology, 69978, Ramat Aviv, Israel
| | - Manuel Tena-Sempere
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14071, Cordoba, Spain.,Instituto Maimonides de Investigacion Biomedica (IMIBIC/HURS), 14004, Cordoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Nelly Pitteloud
- Pediatrics, Division of Pediatric Endocrinology, Diabetology and Obesity, University Hospital Lausanne (CHUV), 1011, Lausanne, Switzerland
| | - Riitta Veijola
- Department of Children and Adolescents, Oulu University Hospital, 90029, Oulu, Finland.,Department of Pediatrics, PEDEGO Research Center, Medical Research Center, University of Oulu, 90014, Oulu, Finland
| | - Marita Lipsanen-Nyman
- Children's Hospital, Pediatric Research Center, Helsinki University Central Hospital (HUCH), 00029, Helsinki, Finland
| | - Kari Kaunisto
- Department of Children and Adolescents, Oulu University Hospital, 90029, Oulu, Finland
| | - Patrice Mollard
- IGF, CNRS, INSERM, Univ. Montpellier, F-34094, Montpellier, France
| | - Cynthia L Andoniadou
- Centre for Craniofacial and Regenerative Biology, King's College London, Floor 27 Tower Wing, Guy's Campus, London, SE1 9RT, UK.,Department of Internal Medicine III, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany
| | - Joel A Hirsch
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Institute of Structural Biology, 69978, Ramat Aviv, Israel
| | - Markku Varjosalo
- Institute of Biotechnology, Biocenter 3, University of Helsinki, 00014, Helsinki, Finland
| | - Thomas Jespersen
- Department of Biomedical Sciences, University of Copenhagen, 2200, Copenhagen N, Denmark
| | - Taneli Raivio
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland. .,Children's Hospital, Pediatric Research Center, Helsinki University Central Hospital (HUCH), 00029, Helsinki, Finland.
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22
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Abbott GW. Chansporter complexes in cell signaling. FEBS Lett 2017; 591:2556-2576. [PMID: 28718502 DOI: 10.1002/1873-3468.12755] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 07/03/2017] [Accepted: 07/12/2017] [Indexed: 12/11/2022]
Abstract
Ion channels facilitate diffusion of ions across cell membranes for such diverse purposes as neuronal signaling, muscular contraction, and fluid homeostasis. Solute transporters often utilize ionic gradients to move aqueous solutes up their concentration gradient, also fulfilling a wide variety of tasks. Recently, an increasing number of ion channel-transporter ('chansporter') complexes have been discovered. Chansporter complex formation may overcome what could otherwise be considerable spatial barriers to rapid signal integration and feedback between channels and transporters, the ions and other substrates they transport, and environmental factors to which they must respond. Here, current knowledge in this field is summarized, covering both heterologous expression structure/function findings and potential mechanisms by which chansporter complexes fulfill contrasting roles in cell signaling in vivo.
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Affiliation(s)
- Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA
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