1
|
McKenna MJ, Gong X, Petersen AC, Sostaric S, Goodman CA, Garnham A, Aw TJ, Steward CH, Murphy KT, Carey KA, Krum H, Snow RJ, Cameron-Smith D. Digoxin and exercise effects on skeletal muscle Na +,K +-ATPase isoform gene expression in healthy humans. Exp Physiol 2024. [PMID: 39222217 DOI: 10.1113/ep091962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Accepted: 08/13/2024] [Indexed: 09/04/2024]
Abstract
In muscle, digoxin inhibits Na+,K+-ATPase (NKA) whereas acute exercise can increase NKA gene expression, consistent with training-induced increased NKA content. We investigated whether oral digoxin increased NKA isoform mRNA expression (qPCR) in muscle at rest, during and post-exercise in 10 healthy adults, who received digoxin (DIG, 0.25 mg per day) or placebo (CON) for 14 days, in a randomised, double-blind and cross-over design. Muscle was biopsied at rest, after cycling 20 min (10 min each at 33%, then 67%V ̇ O 2 peak ${{\dot{V}}_{{{{\mathrm{O}}}_2}{\mathrm{peak}}}}$ ), then to fatigue at 90%V ̇ O 2 peak ${{\dot{V}}_{{{{\mathrm{O}}}_2}{\mathrm{peak}}}}$ and 3 h post-exercise. No differences were found between DIG and CON for NKA α1-3 or β1-3 isoform mRNA. Both α1 (354%, P = 0.001) and β3 mRNA (P = 0.008) were increased 3 h post-exercise, with α2 and β1-2 mRNA unchanged, whilst α3 mRNA declined at fatigue (-43%, P = 0.045). In resting muscle, total β mRNA (∑(β1+β2+β3)) increased in DIG (60%, P = 0.025) and also when transcripts for each isoform were normalised to CON then either summed (P = 0.030) or pooled (n = 30, P = 0.034). In contrast, total α mRNA (∑(α1+α2+α3), P = 0.348), normalised then summed (P = 0.332), or pooled transcripts (n = 30, P = 0.717) did not differ with DIG. At rest, NKA α1-2 and β1-2 protein abundances were unchanged by DIG. Post-exercise, α1 and β1-2 proteins were unchanged, but α2 declined at 3 h (19%, P = 0.020). In conclusion, digoxin did not modify gene expression of individual NKA isoforms at rest or with exercise, indicating NKA gene expression was maintained consistent with protein abundances. However, elevated resting muscle total β mRNA with digoxin suggests a possible underlying β gene-stimulatory effect. HIGHLIGHTS: What is the central question of this study? Na+,K+-ATPase (NKA) in muscle is important for Na+/K+ homeostasis. We investigated whether the NKA-inhibitor digoxin stimulates increased NKA gene expression in muscle and exacerbates NKA gene responses to exercise in healthy adults. What is the main finding and its importance? Digoxin did not modify exercise effects on muscle NKA α1-3 and β1-3 gene transcripts, which comprised increased post-exercise α1 and β3 mRNA and reduced α3 mRNA during exercise. However, in resting muscle, digoxin increased NKA total β isoform mRNA expression. Despite inhibitory-digoxin or acute exercise stressors, NKA gene regulation in muscle is consistent with the maintenance of NKA protein contents.
Collapse
Affiliation(s)
- Michael J McKenna
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Xiaofei Gong
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Aaron C Petersen
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Simon Sostaric
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Craig A Goodman
- Institute for Health and Sport, Victoria University, Melbourne, Australia
- Centre for Muscle Research, Department of Anatomy and Physiology, University of Melbourne, Melbourne, Australia
| | - Andrew Garnham
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Tai-Juan Aw
- Department of Epidemiology and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, Australia
| | - Collene H Steward
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Kate T Murphy
- Institute for Health and Sport, Victoria University, Melbourne, Australia
- Centre for Muscle Research, Department of Anatomy and Physiology, University of Melbourne, Melbourne, Australia
| | - Kate A Carey
- Institute for Breathing and Sleep, Melbourne, Australia
| | - Henry Krum
- Department of Epidemiology and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, Australia
| | - Rodney J Snow
- Institute of Physical Activity and Nutrition, School of Exercise and Nutrition Sciences, Deakin University, Melbourne, Australia
| | - David Cameron-Smith
- Department of Nutrition, Singapore Institute of Food and Biotechnology Innovation (SIFBI), Singapore, Singapore
| |
Collapse
|
2
|
Ponce-Balbuena D, Tyrrell DJ, Cruz-Cortés C, Guerrero-Serna G, Da Rocha AM, Herron TJ, Song J, Raza DS, Anumonwo J, Goldstein DR, Espinoza-Fonseca LM. Paradoxical SERCA dysregulation contributes to atrial fibrillation in a model of diet-induced obesity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.02.606385. [PMID: 39149279 PMCID: PMC11326153 DOI: 10.1101/2024.08.02.606385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
Obesity is a major risk factor for atrial fibrillation (AF) the most common serious cardiac arrhythmia, but the molecular mechanisms underlying diet-induced AF remain unclear. In this study, we subjected mice to a chronic high-fat diet and acute sympathetic activation ('two-hit' model) to study the mechanisms by which diet-induced obesity promotes AF. Surface electrocardiography revealed that diet-induced obesity and sympathetic activation synergize during intracardiac tachypacing to induce AF. At the cellular level, diet-induced obesity and acute adrenergic stimulation facilitate the formation of delayed afterdepolarizations in atrial myocytes, implicating altered Ca2+ dynamics as the underlying cause of AF. We found that diet-induced obesity does not alter the expression of major Ca2+-handling proteins in atria, including the sarcoplasmic reticulum Ca2+-ATPase (SERCA), a major component of beat-to-beat Ca2+ cycling in the heart. Paradoxically, obesity reduces phospholamban phosphorylation, suggesting decreased SERCA activity, yet atrial myocytes from obese mice showed a significantly increased Ca2+ transient amplitude and SERCA-mediated Ca2+ uptake. Adrenergic stimulation further increases the Ca2+ transient amplitude but does not affect Ca2+ reuptake in atrial myocytes from obese mice. Transcriptomics analysis showed that a high-fat diet prompts upregulation of neuronatin, a protein that has been implicated in obesity and is known to stimulate SERCA activity. We propose a mechanism in which obesity primes SERCA for paradoxical activation, and adrenergic stimulation facilitates AF conversion through a Ca2+-induced Ca2+ release gain in atrial myocytes. Overall, this study links obesity, altered Ca2+ signaling, and AF, and targeting this mechanism may prove effective for treating obesity-induced AF.
Collapse
Affiliation(s)
- Daniela Ponce-Balbuena
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Center for Arrhythmia Research, University of Michigan, MI 48109, USA
| | - Daniel J. Tyrrell
- Graduate Program in Immunology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Carlos Cruz-Cortés
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Center for Arrhythmia Research, University of Michigan, MI 48109, USA
| | - Guadalupe Guerrero-Serna
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Center for Arrhythmia Research, University of Michigan, MI 48109, USA
| | - Andre Monteiro Da Rocha
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Center for Arrhythmia Research, University of Michigan, MI 48109, USA
| | - Todd J. Herron
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Center for Arrhythmia Research, University of Michigan, MI 48109, USA
| | - Jianrui Song
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Danyal S. Raza
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Center for Arrhythmia Research, University of Michigan, MI 48109, USA
| | - Justus Anumonwo
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Center for Arrhythmia Research, University of Michigan, MI 48109, USA
| | - Daniel R. Goldstein
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Graduate Program in Immunology, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Microbiology and Immunology, University of Michigan, MI 48109, USA
| | - L. Michel Espinoza-Fonseca
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
- Center for Arrhythmia Research, University of Michigan, MI 48109, USA
| |
Collapse
|
3
|
Cao XY, Liu Y, Kan JS, Huang XX, Kambey PA, Zhang CT, Gao J. Microglial SIX2 suppresses lipopolysaccharide (LPS)-induced neuroinflammation by up-regulating FXYD2 expression. Brain Res Bull 2024; 212:110970. [PMID: 38688414 DOI: 10.1016/j.brainresbull.2024.110970] [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: 01/07/2024] [Revised: 04/15/2024] [Accepted: 04/26/2024] [Indexed: 05/02/2024]
Abstract
Parkinson's disease (PD) is a severe neurodegenerative disease associated with the loss of dopaminergic (DA) neurons in the substantia nigra (SN). Although its pathogenesis remains unclear, microglia-mediated neuroinflammation significantly contributes to the development of PD. Here we showed that the sine oculis homeobox (SIX) homologue family transcription factors SIX2 exerted significant effects on neuroinflammation. The SIX2 protein, which is silenced during development, was reactivated in lipopolysaccharide (LPS)-treated microglia. The reactivated SIX2 in microglia mitigated the LPS induced inflammatory effects, and then reduced the toxic effect of conditioned media (CM) of microglia on co-cultured MES23.5 DA cells. Using the LPS-stimulated Cx3cr1-CreERT2 mouse model, we also demonstrated that the highly-expressed SIX2 in microglia obviously attenuated neuroinflammation and protected the DA neurons in SN. Further RNA-Seq analysis on the inflammatory activated microglia revealed that the SIX2 exerted these effects via up-regulating the FXYD domain containing ion transport regulator 2 (FXYD2). Taken together, our study demonstrated that SIX2 was an endogenous anti-inflammatory factor in microglia, and it exerted anti-neuroinflammatory effects by regulating the expression of FXYD2, which provides new ideas for anti-neuroinflammation in PD.
Collapse
Affiliation(s)
- Xia-Yin Cao
- Department of Neurobiology and Cellular biology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Yi Liu
- Department of Neurobiology and Cellular biology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Jia-Shuo Kan
- Department of Neurobiology and Cellular biology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Xin-Xing Huang
- Department of Neurobiology and Cellular biology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Piniel Alphayo Kambey
- Department of Neurobiology and Cellular biology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Can-Tang Zhang
- Department of Respiratory and Critical Care, the Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Jin Gao
- Department of Neurobiology and Cellular biology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China.
| |
Collapse
|
4
|
Contreras RG, Torres-Carrillo A, Flores-Maldonado C, Shoshani L, Ponce A. Na +/K +-ATPase: More than an Electrogenic Pump. Int J Mol Sci 2024; 25:6122. [PMID: 38892309 PMCID: PMC11172918 DOI: 10.3390/ijms25116122] [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: 03/26/2024] [Revised: 05/20/2024] [Accepted: 05/23/2024] [Indexed: 06/21/2024] Open
Abstract
The sodium pump, or Na+/K+-ATPase (NKA), is an essential enzyme found in the plasma membrane of all animal cells. Its primary role is to transport sodium (Na+) and potassium (K+) ions across the cell membrane, using energy from ATP hydrolysis. This transport creates and maintains an electrochemical gradient, which is crucial for various cellular processes, including cell volume regulation, electrical excitability, and secondary active transport. Although the role of NKA as a pump was discovered and demonstrated several decades ago, it remains the subject of intense research. Current studies aim to delve deeper into several aspects of this molecular entity, such as describing its structure and mode of operation in atomic detail, understanding its molecular and functional diversity, and examining the consequences of its malfunction due to structural alterations. Additionally, researchers are investigating the effects of various substances that amplify or decrease its pumping activity. Beyond its role as a pump, growing evidence indicates that in various cell types, NKA also functions as a receptor for cardiac glycosides like ouabain. This receptor activity triggers the activation of various signaling pathways, producing significant morphological and physiological effects. In this report, we present the results of a comprehensive review of the most outstanding studies of the past five years. We highlight the progress made regarding this new concept of NKA and the various cardiac glycosides that influence it. Furthermore, we emphasize NKA's role in epithelial physiology, particularly its function as a receptor for cardiac glycosides that trigger intracellular signals regulating cell-cell contacts, proliferation, differentiation, and adhesion. We also analyze the role of NKA β-subunits as cell adhesion molecules in glia and epithelial cells.
Collapse
Affiliation(s)
| | | | | | | | - Arturo Ponce
- Department of Physiology, Biophysics and Neurosciences, CINVESTAV-IPN, Mexico City 07360, Mexico; (R.G.C.); (A.T.-C.); (C.F.-M.); (L.S.)
| |
Collapse
|
5
|
Blaustein MP, Hamlyn JM. Sensational site: the sodium pump ouabain-binding site and its ligands. Am J Physiol Cell Physiol 2024; 326:C1120-C1177. [PMID: 38223926 PMCID: PMC11193536 DOI: 10.1152/ajpcell.00273.2023] [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: 06/22/2023] [Revised: 12/22/2023] [Accepted: 01/10/2024] [Indexed: 01/16/2024]
Abstract
Cardiotonic steroids (CTS), used by certain insects, toads, and rats for protection from predators, became, thanks to Withering's trailblazing 1785 monograph, the mainstay of heart failure (HF) therapy. In the 1950s and 1960s, we learned that the CTS receptor was part of the sodium pump (NKA) and that the Na+/Ca2+ exchanger was critical for the acute cardiotonic effect of digoxin- and ouabain-related CTS. This "settled" view was upended by seven revolutionary observations. First, subnanomolar ouabain sometimes stimulates NKA while higher concentrations are invariably inhibitory. Second, endogenous ouabain (EO) was discovered in the human circulation. Third, in the DIG clinical trial, digoxin only marginally improved outcomes in patients with HF. Fourth, cloning of NKA in 1985 revealed multiple NKA α and β subunit isoforms that, in the rodent, differ in their sensitivities to CTS. Fifth, the NKA is a cation pump and a hormone receptor/signal transducer. EO binding to NKA activates, in a ligand- and cell-specific manner, several protein kinase and Ca2+-dependent signaling cascades that have widespread physiological effects and can contribute to hypertension and HF pathogenesis. Sixth, all CTS are not equivalent, e.g., ouabain induces hypertension in rodents while digoxin is antihypertensinogenic ("biased signaling"). Seventh, most common rodent hypertension models require a highly ouabain-sensitive α2 NKA and the elevated blood pressure is alleviated by EO immunoneutralization. These numerous phenomena are enabled by NKA's intricate structure. We have just begun to understand the endocrine role of the endogenous ligands and the broad impact of the ouabain-binding site on physiology and pathophysiology.
Collapse
Affiliation(s)
- Mordecai P Blaustein
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States
| | - John M Hamlyn
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States
| |
Collapse
|
6
|
McKenna MJ, Renaud JM, Ørtenblad N, Overgaard K. A century of exercise physiology: effects of muscle contraction and exercise on skeletal muscle Na +,K +-ATPase, Na + and K + ions, and on plasma K + concentration-historical developments. Eur J Appl Physiol 2024; 124:681-751. [PMID: 38206444 PMCID: PMC10879387 DOI: 10.1007/s00421-023-05335-9] [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: 02/02/2023] [Accepted: 09/27/2023] [Indexed: 01/12/2024]
Abstract
This historical review traces key discoveries regarding K+ and Na+ ions in skeletal muscle at rest and with exercise, including contents and concentrations, Na+,K+-ATPase (NKA) and exercise effects on plasma [K+] in humans. Following initial measures in 1896 of muscle contents in various species, including humans, electrical stimulation of animal muscle showed K+ loss and gains in Na+, Cl- and H20, then subsequently bidirectional muscle K+ and Na+ fluxes. After NKA discovery in 1957, methods were developed to quantify muscle NKA activity via rates of ATP hydrolysis, Na+/K+ radioisotope fluxes, [3H]-ouabain binding and phosphatase activity. Since then, it became clear that NKA plays a central role in Na+/K+ homeostasis and that NKA content and activity are regulated by muscle contractions and numerous hormones. During intense exercise in humans, muscle intracellular [K+] falls by 21 mM (range - 13 to - 39 mM), interstitial [K+] increases to 12-13 mM, and plasma [K+] rises to 6-8 mM, whilst post-exercise plasma [K+] falls rapidly, reflecting increased muscle NKA activity. Contractions were shown to increase NKA activity in proportion to activation frequency in animal intact muscle preparations. In human muscle, [3H]-ouabain-binding content fully quantifies NKA content, whilst the method mainly detects α2 isoforms in rats. Acute or chronic exercise affects human muscle K+, NKA content, activity, isoforms and phospholemman (FXYD1). Numerous hormones, pharmacological and dietary interventions, altered acid-base or redox states, exercise training and physical inactivity modulate plasma [K+] during exercise. Finally, historical research approaches largely excluded female participants and typically used very small sample sizes.
Collapse
Affiliation(s)
- Michael J McKenna
- Institute for Health and Sport, Victoria University, Melbourne, VIC, 8001, Australia.
- College of Physical Education, Southwest University, Chongqing, China.
- College of Sport Science, Zhuhai College of Science and Technology, Zhuhai, China.
| | - Jean-Marc Renaud
- Department of Cellular and Molecular Medicine, Neuromuscular Research Center, University of Ottawa, Ottawa, ON, Canada
| | - Niels Ørtenblad
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Kristian Overgaard
- Exercise Biology, Department of Public Health, Aarhus University, Aarhus, Denmark
| |
Collapse
|
7
|
Xie H, Li J, Lu M, Zhang R, Mao H. miR-1180 Targets FXYD5 to Regulate Pancreatic Cancer Cells Migration and Invasion. Mol Biotechnol 2023:10.1007/s12033-023-00923-8. [PMID: 38155284 DOI: 10.1007/s12033-023-00923-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Accepted: 09/22/2023] [Indexed: 12/30/2023]
Abstract
Pancreatic cancer is a fatal malignancy typically diagnosed in older males and has an aggressive progression. The function of the miR-1180/FXYD5 axis in pancreatic cancer malignant behaviors was investigated. 20 pairs of pancreatic cancer and adjacent normal tissue samples were harvested from pancreatic cancer patients, and qRT-PCR, IHC, and western blot assays were performed, respectively, to detect the mRNA expression and protein levels of miR-1180 or FXYD5. Transwell and scratch assays were conducted to detect the migratory and invasive ability of pancreatic cancer cells; a Dual-luciferase reporter assay was employed to validate miR-1180 targeting FXYD5. miR-1180 targeting FXYD5 to regulate the migratory and invasive ability of pancreatic cancer cells was validated in mouse xenograft tumor models. FXYD5 expression was increased in pancreatic cancer tissue samples than in adjacent normal tissue samples (P < 0.01), and FXYD5 expression exhibited a positive correlation with the migratory and invasive ability of pancreatic cancer cells. miR-1180 targeted FXYD5 and negatively regulated FXYD5. Restoring miR-1180 expression could inhibit the migratory and invasive ability of pancreatic cancer cells (P < 0.01), and this effect could potentially be alleviated by FXYD5 overexpression. The miR-1180/FXYD5 axis positively regulated E-cadherin and negatively regulated MMP2 and MMP9 expression levels. In vivo findings demonstrated that miR-1180 overexpression inhibited tumor growth and lung metastasis (P < 0.05), while FXYD5 overexpression promoted tumor growth and lung metastasis (P < 0.05). In conclusion, the miR-1180 /FXYD5 axis could be involved in pancreatic cancer metastasis through the regulation of EMT and extracellular matrix degradation.
Collapse
Affiliation(s)
- Hongmin Xie
- Department of Gastroenterology, Zhujiang Hospital of Southern Medical University, No. 253 Industrial Road, Guangzhou, 510280, Guangdong, China
- Department of Gastroenterology, Zhongshan Chenxinghai Hospital of Integrated Traditional Chinese and Western Medicine, Zhongshan, 528415, Guangdong, China
| | - Jiaxuan Li
- Department of Gastroenterology, Zhongshan Chenxinghai Hospital of Integrated Traditional Chinese and Western Medicine, Zhongshan, 528415, Guangdong, China
| | - Min Lu
- Department of Gastroenterology, Zhujiang Hospital of Southern Medical University, No. 253 Industrial Road, Guangzhou, 510280, Guangdong, China
| | - Ruijiang Zhang
- Department of Gastroenterology, Zhongshan Chenxinghai Hospital of Integrated Traditional Chinese and Western Medicine, Zhongshan, 528415, Guangdong, China
| | - Hua Mao
- Department of Gastroenterology, Zhujiang Hospital of Southern Medical University, No. 253 Industrial Road, Guangzhou, 510280, Guangdong, China.
| |
Collapse
|
8
|
Zhao E, Gao K, Xiong J, Liu Z, Chen Y, Yi L. The roles of FXYD family members in ovarian cancer: an integrated analysis by mining TCGA and GEO databases and functional validations. J Cancer Res Clin Oncol 2023; 149:17269-17284. [PMID: 37814066 DOI: 10.1007/s00432-023-05445-z] [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: 08/04/2023] [Accepted: 09/23/2023] [Indexed: 10/11/2023]
Abstract
BACKGROUND The FXYD family of ion transport regulators have emerged as important modulators of cancer progression and metastasis. However, their expression and roles in ovarian cancer (OCa) have not been systematically investigated. METHODS The expression of FXYD genes in OCa was analyzed using data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO), as well as independent clinical samples. The prognostic values of FXYD genes were evaluated by Kaplan-Meier and Cox regression analysis. To explore potential mechanisms, bioinformatics approaches including Gene Ontology, KEGG pathway analysis, GSEA and drug sensitivity correlation analysis were performed. OCa cell lines overexpressing FXYD1, FXYD5 or FXYD7 were also generated and their impacts on proliferation, migration and invasion were assessed. RESULTS FXYD1 and FXYD6 were significantly downregulated while FXYD3, FXYD4 and FXYD5 were upregulated in OCa tissues compared to normal tissues. FXYD1, FXYD5 and FXYD7 were independent adverse prognostic factors for OCa patients. Pathway and drug correlation analysis revealed that FXYD1, FXYD5 and FXYD7 genes regulated diverse oncogenic signaling cascades and modulated the response to various chemotherapeutic agents. Overexpression of FXYD1, FXYD5 or FXYD7 enhanced OCa cell motility and invasiveness in vitro. CONCLUSION Our results demonstrate aberrant expression patterns, prognostic values, and oncogenic activities of FXYD genes in OCa. FXYD1, FXYD5 and FXYD7 may serve as biomarkers and therapeutic targets for this disease. Targeting FXYD-mediated signaling represents a promising therapeutic strategy against OCa.
Collapse
Affiliation(s)
- Eryong Zhao
- Department of Obstetrics and Gynecology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, 9 Jinsui Road, Guangzhou, 510623, People's Republic of China
| | - Kefei Gao
- Department of Obstetrics and Gynecology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, 9 Jinsui Road, Guangzhou, 510623, People's Republic of China
| | - Jian Xiong
- Department of Obstetrics and Gynecology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, 9 Jinsui Road, Guangzhou, 510623, People's Republic of China
| | - Zhihong Liu
- Department of Obstetrics and Gynecology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, 9 Jinsui Road, Guangzhou, 510623, People's Republic of China
| | - Yuelin Chen
- Department of Obstetrics and Gynecology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, 9 Jinsui Road, Guangzhou, 510623, People's Republic of China
| | - Lisha Yi
- Department of Obstetrics and Gynecology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangdong Provincial Clinical Research Center for Child Health, 9 Jinsui Road, Guangzhou, 510623, People's Republic of China.
| |
Collapse
|
9
|
Li M, Nishimura T, Takeuchi Y, Hongu T, Wang Y, Shiokawa D, Wang K, Hirose H, Sasahara A, Yano M, Ishikawa S, Inokuchi M, Ota T, Tanabe M, Tada KI, Akiyama T, Cheng X, Liu CC, Yamashita T, Sugano S, Uchida Y, Chiba T, Asahara H, Nakagawa M, Sato S, Miyagi Y, Shimamura T, Nagai LAE, Kanai A, Katoh M, Nomura S, Nakato R, Suzuki Y, Tojo A, Voon DC, Ogawa S, Okamoto K, Foukakis T, Gotoh N. FXYD3 functionally demarcates an ancestral breast cancer stem cell subpopulation with features of drug-tolerant persisters. J Clin Invest 2023; 133:e166666. [PMID: 37966117 PMCID: PMC10645391 DOI: 10.1172/jci166666] [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: 11/08/2022] [Accepted: 09/21/2023] [Indexed: 11/16/2023] Open
Abstract
The heterogeneity of cancer stem cells (CSCs) within tumors presents a challenge in therapeutic targeting. To decipher the cellular plasticity that fuels phenotypic heterogeneity, we undertook single-cell transcriptomics analysis in triple-negative breast cancer (TNBC) to identify subpopulations in CSCs. We found a subpopulation of CSCs with ancestral features that is marked by FXYD domain-containing ion transport regulator 3 (FXYD3), a component of the Na+/K+ pump. Accordingly, FXYD3+ CSCs evolve and proliferate, while displaying traits of alveolar progenitors that are normally induced during pregnancy. Clinically, FXYD3+ CSCs were persistent during neoadjuvant chemotherapy, hence linking them to drug-tolerant persisters (DTPs) and identifying them as crucial therapeutic targets. Importantly, FXYD3+ CSCs were sensitive to senolytic Na+/K+ pump inhibitors, such as cardiac glycosides. Together, our data indicate that FXYD3+ CSCs with ancestral features are drivers of plasticity and chemoresistance in TNBC. Targeting the Na+/K+ pump could be an effective strategy to eliminate CSCs with ancestral and DTP features that could improve TNBC prognosis.
Collapse
Affiliation(s)
- Mengjiao Li
- Division of Cancer Cell Biology, Cancer Research Institute, and
| | | | - Yasuto Takeuchi
- Division of Cancer Cell Biology, Cancer Research Institute, and
- Institute for Frontier Science Initiative, Kanazawa University, Kanazawa City, Japan
| | - Tsunaki Hongu
- Division of Cancer Cell Biology, Cancer Research Institute, and
| | - Yuming Wang
- Division of Cancer Cell Biology, Cancer Research Institute, and
| | - Daisuke Shiokawa
- Division of Cancer Differentiation, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan
| | - Kang Wang
- Department of Oncology-Pathology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
| | - Haruka Hirose
- Division of Systems Biology, Graduate School of Medicine, Nagoya University, Nagoya City, Japan
| | - Asako Sasahara
- Department of Breast and Endocrine Surgery, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Masao Yano
- Department of Surgery, Minami-machida Hospital, Machida City, Tokyo, Japan
| | - Satoko Ishikawa
- Department of Breast Oncology, Kanazawa University Hospital, Kanazawa City, Japan
| | - Masafumi Inokuchi
- Department of Breast Oncology, Kanazawa University Hospital, Kanazawa City, Japan
| | - Tetsuo Ota
- Department of Breast Oncology, Kanazawa University Hospital, Kanazawa City, Japan
| | - Masahiko Tanabe
- Department of Breast and Endocrine Surgery, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Kei-ichiro Tada
- Department of Breast and Endocrine Surgery, Nihon University, Itabashi-ku, Tokyo, Japan
| | - Tetsu Akiyama
- Laboratory of Molecular and Genetic Information, Institute for Quantitative Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Xi Cheng
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Chia-Chi Liu
- North Shore Heart Research Group, Kolling Institute, University of Sydney, Sydney, New South Wales, Australia
| | - Toshinari Yamashita
- Department of Breast and Endocrine Surgery, Kanagawa Cancer Center, Yokohama City, Kanagawa, Japan
| | - Sumio Sugano
- Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| | - Yutaro Uchida
- Department of Systems Biomedicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| | - Tomoki Chiba
- Department of Systems Biomedicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| | - Hiroshi Asahara
- Department of Systems Biomedicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
| | - Masahiro Nakagawa
- Department of Pathology and Tumor Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Shinya Sato
- Molecular Pathology and Genetics Division, Kanagawa Cancer Center Research Institute, Yokohama City, Kanagawa, Japan
| | - Yohei Miyagi
- Molecular Pathology and Genetics Division, Kanagawa Cancer Center Research Institute, Yokohama City, Kanagawa, Japan
| | - Teppei Shimamura
- Division of Systems Biology, Graduate School of Medicine, Nagoya University, Nagoya City, Japan
| | | | - Akinori Kanai
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Biosciences
| | - Manami Katoh
- Department of Cardiovascular Medicine, Graduate School of Medicine
- Genome Science Division, Research Center for Advanced Science and Technology
| | - Seitaro Nomura
- Department of Cardiovascular Medicine, Graduate School of Medicine
- Genome Science Division, Research Center for Advanced Science and Technology
- Department of Frontier Cardiovascular Science, Graduate School of Medicine, and
| | - Ryuichiro Nakato
- Laboratory of Computational Genomics, Institute for Quantitative Biosciences
| | - Yutaka Suzuki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Biosciences
| | - Arinobu Tojo
- Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
- Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Dominic C. Voon
- Institute for Frontier Science Initiative, Kanazawa University, Kanazawa City, Japan
- Inflammation and Epithelial Plasticity Unit, Cancer Research Institute, Kanazawa University, Kanazawa City, Japan
| | - Seishi Ogawa
- Department of Pathology and Tumor Biology, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Koji Okamoto
- Division of Cancer Differentiation, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan
- Advanced Comprehensive Research Organization, Teikyo University, Itabashi-ku, Tokyo, Japan
| | - Theodoros Foukakis
- Department of Oncology-Pathology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
| | - Noriko Gotoh
- Division of Cancer Cell Biology, Cancer Research Institute, and
- Institute for Frontier Science Initiative, Kanazawa University, Kanazawa City, Japan
| |
Collapse
|
10
|
Palmgren M. Evolution of the sodium pump. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119511. [PMID: 37301269 DOI: 10.1016/j.bbamcr.2023.119511] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/16/2023] [Accepted: 06/02/2023] [Indexed: 06/12/2023]
Abstract
Eukaryotic plasma membranes (PMs) are energized by electrogenic P-type ATPases that generate either Na+ or H+ motive forces to drive Na+ and H+ dependent transport processes, respectively. For this purpose, animal rely on Na+/K+-ATPases whereas fungi and plants employ PM H+-ATPases. Prokaryotes, on the other hand, depend on H+ or Na+-motive electron transport complexes to energize their cell membranes. This raises the question as to why and when electrogenic Na+ and H+ pumps evolved? Here it is shown that prokaryotic Na+/K+-ATPases have near perfect conservation of binding sites involved in coordination of three Na+ and two K+ ions. Such pumps are rare in Eubacteria but are common in methanogenic Archaea where they often are found together with P-type putative PM H+-ATPases. With some exceptions, Na+/K+-ATPases and PM H+-ATPases are found everywhere in the eukaryotic tree of life, but never together in animals, fungi and land plants. It is hypothesized that Na+/K+-ATPases and PM H+-ATPases evolved in methanogenic Archaea to support the bioenergetics of these ancestral organisms, which can utilize both H+ and Na+ as energy currencies. Both pumps must have been simultaneously present in the first eukaryotic cell, but during diversification of the major eukaryotic kingdoms, and at the time animals diverged from fungi, animals kept Na+/K+-ATPases but lost PM H+-ATPases. At the same evolutionary branch point, fungi did loose Na+/K+-ATPases, and their role was taken over by PM H+-ATPases. An independent but similar scenery emerged during terrestrialization of plants: they lost Na+/K+-ATPases but kept PM H+-ATPases.
Collapse
Affiliation(s)
- Michael Palmgren
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
| |
Collapse
|
11
|
Karbowski M, Boyman L, Garber L, Joca HC, Verhoeven N, Coleman AK, Ward CW, Lederer WJ, Greiser M. Na + /K + ATPase-Ca v 1.2 nanodomain differentially regulates intracellular [Na + ], [Ca 2+ ] and local adrenergic signaling in cardiac myocytes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.31.553598. [PMID: 37693446 PMCID: PMC10491240 DOI: 10.1101/2023.08.31.553598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Background The intracellular Na + concentration ([Na + ] i ) is a crucial but understudied regulator of cardiac myocyte function. The Na + /K + ATPase (NKA) controls the steady-state [Na + ] i and thereby determines the set-point for intracellular Ca 2+ . Here, we investigate the nanoscopic organization and local adrenergic regulation of the NKA macromolecular complex and how it differentially regulates the intracellular Na + and Ca 2+ homeostases in atrial and ventricular myocytes. Methods Multicolor STORM super-resolution microscopy, Western Blot analyses, and in vivo examination of adrenergic regulation are employed to examine the organization and function of Na + nanodomains in cardiac myocytes. Quantitative fluorescence microscopy at high spatiotemporal resolution is used in conjunction with cellular electrophysiology to investigate intracellular Na + homeostasis in atrial and ventricular myocytes. Results The NKAα1 (NKAα1) and the L-type Ca 2+ -channel (Ca v 1.2) form a nanodomain with a center-to center distance of ∼65 nm in both ventricular and atrial myocytes. NKAα1 protein expression levels are ∼3 fold higher in atria compared to ventricle. 100% higher atrial I NKA , produced by large NKA "superclusters", underlies the substantially lower Na + concentration in atrial myocytes compared to the benchmark values set in ventricular myocytes. The NKA's regulatory protein phospholemman (PLM) has similar expression levels across atria and ventricle resulting in a much lower PLM/NKAα1 ratio for atrial compared to ventricular tissue. In addition, a huge PLM phosphorylation reserve in atrial tissue produces a high ß-adrenergic sensitivity of I NKA in atrial myocytes. ß-adrenergic regulation of I NKA is locally mediated in the NKAα1-Ca v 1.2 nanodomain via A-kinase anchoring proteins. Conclusions NKAα1, Ca v 1.2 and their accessory proteins form a structural and regulatory nanodomain at the cardiac dyad. The tissue-specific composition and local adrenergic regulation of this "signaling cloud" is a main regulator of the distinct global intracellular Na + and Ca 2+ concentrations in atrial and ventricular myocytes.
Collapse
|
12
|
Phillips TA, Hauck GT, Pribadi MP, Cho EE, Cleary SR, Robia SL. Micropeptide hetero-oligomerization adds complexity to the calcium pump regulatory network. Biophys J 2023; 122:301-309. [PMID: 36523160 PMCID: PMC9892615 DOI: 10.1016/j.bpj.2022.12.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 10/24/2022] [Accepted: 12/09/2022] [Indexed: 12/16/2022] Open
Abstract
The sarco(endo)plasmic reticulum calcium ATPase (SERCA) is an ion transporter that creates and maintains intracellular calcium stores. SERCA is inhibited or stimulated by several membrane micropeptides including another-regulin, dwarf open reading frame, endoregulin, phospholamban (PLB), and sarcolipin. We previously showed that these micropeptides assemble into homo-oligomeric complexes with varying affinity. Here, we tested whether different micropeptides can interact with each other, hypothesizing that coassembly into hetero-oligomers may affect micropeptide bioavailability to regulate SERCA. We quantified the relative binding affinity of each combination of candidates using automated fluorescence resonance energy transfer microscopy. All pairs were capable of interacting with good affinity, similar to the affinity of micropeptide self-binding (homo-oligomerization). Testing each pair at a 1:5 ratio and a reciprocal 5:1 ratio, we noted that the affinity of hetero-oligomerization of some micropeptides depended on whether they were the minority or majority species. In particular, sarcolipin was able to join oligomers when it was the minority species but did not readily accommodate other micropeptides in the reciprocal experiment when it was expressed in fivefold excess. The opposite was observed for endoregulin. PLB was a universal partner for all other micropeptides tested, forming avid hetero-oligomers whether it was the minority or majority species. Increasing expression of SERCA decreased PLB-dwarf open reading frame hetero-oligomerization, suggesting that SERCA-micropeptide interactions compete with micropeptide-micropeptide interactions. Thus, micropeptides populate a regulatory network of diverse protein assemblies. The data suggest that the complexity of this interactome increases exponentially with the number of micropeptides that are coexpressed in a particular tissue.
Collapse
Affiliation(s)
- Taylor A Phillips
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois
| | - Garrett T Hauck
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois
| | - Marsha P Pribadi
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois
| | - Ellen E Cho
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois
| | - Sean R Cleary
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois
| | - Seth L Robia
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois.
| |
Collapse
|
13
|
Obradovic M, Sudar-Milovanovic E, Gluvic Z, Banjac K, Rizzo M, Isenovic ER. The Na +/K +-ATPase: A potential therapeutic target in cardiometabolic diseases. Front Endocrinol (Lausanne) 2023; 14:1150171. [PMID: 36926029 PMCID: PMC10011626 DOI: 10.3389/fendo.2023.1150171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 02/14/2023] [Indexed: 03/08/2023] Open
Abstract
Cardiometabolic diseases (CMD) are a direct consequence of modern living and contribute to the development of multisystem diseases such as cardiovascular diseases and diabetes mellitus (DM). CMD has reached epidemic proportions worldwide. A sodium pump (Na+/K+-ATPase) is found in most eukaryotic cells' membrane and controls many essential cellular functions directly or indirectly. This ion transporter and its isoforms are important in the pathogenesis of some pathological processes, including CMD. The structure and function of Na+/K+-ATPase, its expression and distribution in tissues, and its interactions with known ligands such as cardiotonic steroids and other suspected endogenous regulators are discussed in this review. In addition, we reviewed recent literature data related to the involvement of Na+/K+-ATPase activity dysfunction in CMD, focusing on the Na+/K+-ATPase as a potential therapeutic target in CMD.
Collapse
Affiliation(s)
- Milan Obradovic
- Department of Radiobiology and Molecular Genetics, “VINČA“ Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Emina Sudar-Milovanovic
- Department of Radiobiology and Molecular Genetics, “VINČA“ Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Zoran Gluvic
- University Clinical-Hospital Centre Zemun-Belgrade, Clinic of Internal medicine, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Katarina Banjac
- Department of Radiobiology and Molecular Genetics, “VINČA“ Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Manfredi Rizzo
- School of Medicine, Promise Department, University of Palermo, Palermo, Italy
- *Correspondence: Manfredi Rizzo,
| | - Esma R. Isenovic
- Department of Radiobiology and Molecular Genetics, “VINČA“ Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
| |
Collapse
|
14
|
Blaustein MP, Gottlieb SS, Hamlyn JM, Leenen FHH. Whither digitalis? What we can still learn from cardiotonic steroids about heart failure and hypertension. Am J Physiol Heart Circ Physiol 2022; 323:H1281-H1295. [PMID: 36367691 DOI: 10.1152/ajpheart.00362.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Cloning of the "Na+ pump" (Na+,K+-ATPase or NKA) and identification of a circulating ligand, endogenous ouabain (EO), a cardiotonic steroid (CTS), triggered seminal discoveries regarding EO and its NKA receptor in cardiovascular function and the pathophysiology of heart failure (HF) and hypertension. Cardiotonic digitalis preparations were a preferred treatment for HF for two centuries, but digoxin was only marginally effective in a large clinical trial (1997). This led to diminished digoxin use. Missing from the trial, however, was any consideration that endogenous CTS might influence digitalis' efficacy. Digoxin, at therapeutic concentrations, acutely inhibits NKA but, remarkably, antagonizes ouabain's action. Prolonged treatment with ouabain, but not digoxin, causes hypertension in rodents; in this model, digoxin lowers blood pressure (BP). Furthermore, NKA-bound ouabain and digoxin modulate different protein kinase signaling pathways and have disparate long-term cardiovascular effects. Reports of "brain ouabain" led to the elucidation of a new, slow neuromodulatory pathway in the brain; locally generated EO and the α2 NKA isoform help regulate sympathetic drive to the heart and vasculature. The roles of EO and α2 NKA have been studied by EO assay, ouabain-resistant mutation of α2 NKA, and immunoneutralization of EO with ouabain-binding Fab fragments. The NKA α2 CTS binding site and its endogenous ligand are required for BP elevation in many common hypertension models and full expression of cardiac remodeling and dysfunction following pressure overload or myocardial infarction. Understanding how endogenous CTS impact hypertension and HF pathophysiology and therapy should foster reconsideration of digoxin's therapeutic utility.
Collapse
Affiliation(s)
- Mordecai P Blaustein
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland.,Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - Stephen S Gottlieb
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland
| | - John M Hamlyn
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Frans H H Leenen
- Brain and Heart Research Group, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| |
Collapse
|
15
|
Cano Portillo C, Villacreses R, Thurman AL, Pezzulo AA, Zabner J, Thornell IM. FXYD3 facilitates Na + and liquid absorption across human airway epithelia by increasing the transport capacity of the Na/K ATPase. Am J Physiol Cell Physiol 2022; 323:C1044-C1051. [PMID: 35993520 PMCID: PMC9529271 DOI: 10.1152/ajpcell.00047.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 08/15/2022] [Accepted: 08/16/2022] [Indexed: 12/03/2022]
Abstract
Na/K ATPase activity is essential for ion transport across epithelia. FXYD3, a γ subunit of the Na/K ATPase, is expressed in the airway, but its function remains undetermined. Single-cell RNA sequencing and immunohistochemistry revealed that FXYD3 localizes within the basolateral membrane of all airway epithelial cells. To study FXYD3 function, we reduced FXYD3 expression using siRNA. After permeabilizing the apical membrane with nystatin, epithelia pretreated with FXYD3-targeting siRNA had lower ouabain-sensitive short-circuit currents than control epithelia. FXYD3-targeting siRNA also reduced amiloride-sensitive short-circuit currents and liquid absorption across intact epithelia. These data are consistent with FXYD3 facilitating Na+ and liquid absorption. FXYD3 may be needed to maintain the high rates of Na+ and fluid absorption observed for airway and other FXYD3-expressing epithelia.
Collapse
Affiliation(s)
- Camilo Cano Portillo
- Department of Internal Medicine, Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Raul Villacreses
- Department of Internal Medicine, Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Andrew L Thurman
- Department of Internal Medicine, Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Alejandro A Pezzulo
- Department of Internal Medicine, Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Joseph Zabner
- Department of Internal Medicine, Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Ian M Thornell
- Department of Internal Medicine, Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| |
Collapse
|
16
|
Seflova J, Habibi NR, Yap JQ, Cleary SR, Fang X, Kekenes-Huskey PM, Espinoza-Fonseca LM, Bossuyt JB, Robia SL. Fluorescence lifetime imaging microscopy reveals sodium pump dimers in live cells. J Biol Chem 2022; 298:101865. [PMID: 35339486 PMCID: PMC9048134 DOI: 10.1016/j.jbc.2022.101865] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 03/08/2022] [Accepted: 03/10/2022] [Indexed: 12/30/2022] Open
Abstract
The sodium-potassium ATPase (Na/K-ATPase, NKA) establishes ion gradients that facilitate many physiological functions including action potentials and secondary transport processes. NKA comprises a catalytic subunit (alpha) that interacts closely with an essential subunit (beta) and regulatory transmembrane micropeptides called FXYD proteins. In the heart, a key modulatory partner is the FXYD protein phospholemman (PLM, FXYD1), but the stoichiometry of the alpha-beta-PLM regulatory complex is unknown. Here, we used fluorescence lifetime imaging and spectroscopy to investigate the structure, stoichiometry, and affinity of the NKA-regulatory complex. We observed a concentration-dependent binding of the subunits of NKA-PLM regulatory complex, with avid association of the alpha subunit with the essential beta subunit as well as lower affinity alpha-alpha and alpha-PLM interactions. These data provide the first evidence that, in intact live cells, the regulatory complex is composed of two alpha subunits associated with two beta subunits, decorated with two PLM regulatory subunits. Docking and molecular dynamics (MD) simulations generated a structural model of the complex that is consistent with our experimental observations. We propose that alpha-alpha subunit interactions support conformational coupling of the catalytic subunits, which may enhance NKA turnover rate. These observations provide insight into the pathophysiology of heart failure, wherein low NKA expression may be insufficient to support formation of the complete regulatory complex with the stoichiometry (alpha-beta-PLM)2.
Collapse
Affiliation(s)
- Jaroslava Seflova
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois, USA
| | - Nima R Habibi
- Department of Pharmacology, University of California Davis, Davis, California, USA
| | - John Q Yap
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois, USA
| | - Sean R Cleary
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois, USA
| | - Xuan Fang
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois, USA
| | - Peter M Kekenes-Huskey
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois, USA
| | - L Michel Espinoza-Fonseca
- Division of Cardiovascular Medicine, Department of Internal Medicine, Center for Arrhythmia Research, University of Michigan, Ann Arbor, Michigan, USA
| | - Julie B Bossuyt
- Department of Pharmacology, University of California Davis, Davis, California, USA.
| | - Seth L Robia
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, Illinois, USA.
| |
Collapse
|
17
|
Heger T, Zatloukal M, Kubala M, Strnad M, Gruz J. Procyanidin C1 from Viola odorata L. inhibits Na +,K +-ATPase. Sci Rep 2022; 12:7011. [PMID: 35487935 PMCID: PMC9055044 DOI: 10.1038/s41598-022-11086-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 04/13/2022] [Indexed: 01/30/2023] Open
Abstract
Members of the Viola genus play important roles in traditional Asian herbal medicine. This study investigates the ability of Viola odorata L. extracts to inhibit Na+,K+-ATPase, an essential animal enzyme responsible for membrane potential maintenance. The root extract of V. odorata strongly inhibited Na+,K+-ATPase, while leaf and seeds extracts were basically inactive. A UHPLC-QTOF-MS/MS metabolomic approach was used to identify the chemical principle of the root extract’s activity, resulting in the detection of 35,292 features. Candidate active compounds were selected by correlating feature area with inhibitory activity in 14 isolated fractions. This yielded a set of 15 candidate compounds, of which 14 were preliminarily identified as procyanidins. Commercially available procyanidins (B1, B2, B3 and C1) were therefore purchased and their ability to inhibit Na+,K+-ATPase was investigated. Dimeric procyanidins B1, B2 and B3 were found to be inactive, but the trimeric procyanidin C1 strongly inhibited Na+,K+-ATPase with an IC50 of 4.5 µM. This newly discovered inhibitor was docked into crystal structures mimicking the Na3E1∼P·ADP and K2E2·Pi states to identify potential interaction sites within Na+,K+-ATPase. Possible binding mechanisms and the principle responsible for the observed root extract activity are discussed.
Collapse
Affiliation(s)
- Tomas Heger
- Department of Experimental Biology, Faculty of Science, Palacky University, Olomouc, Czech Republic
| | - Marek Zatloukal
- Department of Chemical Biology, Faculty of Science, Palacky University, Olomouc, Czech Republic
| | - Martin Kubala
- Department of Experimental Physics, Faculty of Science, Palacky University, Olomouc, Czech Republic
| | - Miroslav Strnad
- Laboratory of Growth Regulators, Institute of Experimental Botany of the Czech Academy of Sciences, Palacky University, Olomouc, Czech Republic
| | - Jiri Gruz
- Department of Experimental Biology, Faculty of Science, Palacky University, Olomouc, Czech Republic.
| |
Collapse
|
18
|
Biondo ED, Spontarelli K, Ababioh G, Méndez L, Artigas P. Diseases caused by mutations in the Na +/K + pump α1 gene ATP1A1. Am J Physiol Cell Physiol 2021; 321:C394-C408. [PMID: 34232746 DOI: 10.1152/ajpcell.00059.2021] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Human cell survival requires function of the Na+/K+ pump; the heteromeric protein that hydrolyzes ATP to extrude Na+ and import K+ across the plasmalemma, thereby building and maintaining these ions' electrochemical gradients. Numerous dominant diseases caused by mutations in genes encoding for Na+/K+ pump catalytic (α) subunit isoforms highlight the importance of this protein. Here, we review literature describing disorders caused by missense mutations in ATP1A1, the gene encoding the ubiquitously expressed α1 isoform of the Na+/K+ pump. These various maladies include primary aldosteronism with secondary hypertension, an endocrine syndrome, Charcot-Marie-Tooth disease, a peripheral neuropathy, complex spastic paraplegia, another neuromuscular disorder, as well as hypomagnesemia accompanied by seizures and cognitive delay, a condition affecting the renal and central nervous systems. This article focuses on observed commonalities among these mutations' functional effects, as well as on the special characteristics that enable each particular mutation to exclusively affect a certain system, without affecting others. In this respect, it is clear how somatic mutations localized to adrenal adenomas increase aldosterone production without compromising other systems. However, it remains largely unknown how and why some but not all de novo germline or familial mutations (where the mutant must be expressed in numerous tissues) produce a specific disease and not the other diseases. We propose hypotheses to explain this observation and the approaches that we think will drive future research on these debilitating disorders to develop novel patient-specific treatments by combining the use of heterologous protein-expression systems, patient-derived pluripotent cells, and gene-edited cell and mouse models.
Collapse
Affiliation(s)
- Elisa D Biondo
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, Texas
| | - Kerri Spontarelli
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, Texas
| | - Giovanna Ababioh
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, Texas
| | - Lois Méndez
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, Texas
| | - Pablo Artigas
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, Texas
| |
Collapse
|
19
|
Wanichawan P, Skogestad J, Lunde M, Støle TP, Stensland M, Nyman TA, Sjaastad I, Sejersted OM, Aronsen JM, Carlson CR. Design of a Proteolytically Stable Sodium-Calcium Exchanger 1 Activator Peptide for In Vivo Studies. Front Pharmacol 2021; 12:638646. [PMID: 34163352 PMCID: PMC8215385 DOI: 10.3389/fphar.2021.638646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 05/14/2021] [Indexed: 11/13/2022] Open
Abstract
The cardiac sodium–calcium exchanger (NCX1) is important for normal Na+- and Ca2+-homeostasis and cardiomyocyte relaxation and contraction. It has been suggested that NCX1 activity is reduced by phosphorylated phospholemman (pSer68-PLM); however its direct interaction with PLM is debated. Disruption of the potentially inhibitory pSer68-PLM-NCX1 interaction might be a therapeutic strategy to increase NCX1 activity in cardiac disease. In the present study, we aimed to analyze the binding affinities and kinetics of the PLM-NCX1 and pSer68-PLM-NCX1 interactions by surface plasmon resonance (SPR) and to develop a proteolytically stable NCX1 activator peptide for future in vivo studies. The cytoplasmic parts of PLM (PLMcyt) and pSer68-PLM (pSer68-PLMcyt) were found to bind strongly to the intracellular loop of NCX1 (NCX1cyt) with similar KD values of 4.1 ± 1.0 nM and 4.3 ± 1.9 nM, but the PLMcyt-NCX1cyt interaction showed higher on/off rates. To develop a proteolytically stable NCX1 activator, we took advantage of a previously designed, high-affinity PLM binding peptide (OPT) that was derived from the PLM binding region in NCX1 and that reverses the inhibitory PLM (S68D)-NCX1 interaction in HEK293. We performed N- and C-terminal truncations of OPT and identified PYKEIEQLIELANYQV as the minimum sequence required for pSer68-PLM binding. To increase peptide stability in human serum, we replaced the proline with an N-methyl-proline (NOPT) after identification of N-terminus as substitution tolerant by two-dimensional peptide array analysis. Mass spectrometry analysis revealed that the half-life of NOPT was increased 17-fold from that of OPT. NOPT pulled down endogenous PLM from rat left ventricle lysate and exhibited direct pSer68-PLM binding in an ELISA-based assay and bound to pSer68-PLMcyt with a KD of 129 nM. Excess NOPT also reduced the PLMcyt-NCX1cyt interaction in an ELISA-based competition assay, but in line with that NCX1 and PLM form oligomers, NOPT was not able to outcompete the physical interaction between endogenous full length proteins. Importantly, cell-permeable NOPT-TAT increased NCX1 activity in cardiomyocytes isolated from both SHAM-operated and aorta banded heart failure (HF) mice, indicating that NOPT disrupted the inhibitory pSer68-PLM-NCX1 interaction. In conclusion, we have developed a proteolytically stable NCX1-derived PLM binding peptide that upregulates NCX1 activity in SHAM and HF cardiomyocytes.
Collapse
Affiliation(s)
- Pimthanya Wanichawan
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,The KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Jonas Skogestad
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Marianne Lunde
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,The KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Thea Parsberg Støle
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,The KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Maria Stensland
- Department of Immunology, Institute of Clinical Medicine, University of Oslo and Rikshospitalet Oslo, Oslo, Norway
| | - Tuula A Nyman
- Department of Immunology, Institute of Clinical Medicine, University of Oslo and Rikshospitalet Oslo, Oslo, Norway
| | - Ivar Sjaastad
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,The KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Ole M Sejersted
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,The KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Jan Magnus Aronsen
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Pharmacology, Oslo University Hospital Rikshospitalet, Oslo, Norway
| | - Cathrine Rein Carlson
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.,The KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| |
Collapse
|