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Sengupta D, Sengupta K. Lamin A K97E leads to NF-κB-mediated dysfunction of inflammatory responses in dilated cardiomyopathy. Biol Cell 2024; 116:e2300094. [PMID: 38404031 DOI: 10.1111/boc.202300094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/07/2023] [Accepted: 01/04/2024] [Indexed: 02/27/2024]
Abstract
BACKGROUND INFORMATION Lamins are type V intermediate filament proteins underlying the inner nuclear membrane which provide structural rigidity to the nucleus, tether the chromosomes, maintain nuclear homeostasis, and remain dynamically associated with developmentally regulated regions of the genome. A large number of mutations particularly in the LMNA gene encoding lamin A/C results in a wide array of human diseases, collectively termed as laminopathies. Dilated Cardiomyopathy (DCM) is one such laminopathic cardiovascular disease which is associated with systolic dysfunction of left or both ventricles leading to cardiac arrhythmia which ultimately culminates into myocardial infarction. RESULTS In this work, we have unraveled the epigenetic landscape to address the regulation of gene expression in mouse myoblast cell line in the context of the missense mutation LMNA 289A CONCLUSIONS We report here for the first time that there is a significant downregulation of the NF-κB pathway, which has been implicated in cardio-protection elsewhere. SIGNIFICANCE This provides a new pathophysiological explanation that correlates an LMNA mutation and dilated cardiomyopathy.
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Affiliation(s)
- Duhita Sengupta
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, India
- Homi Bhabha National Institute (HBNI), Mumbai, India
| | - Kaushik Sengupta
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, India
- Homi Bhabha National Institute (HBNI), Mumbai, India
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2
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Palacio LC, Durango-Giraldo G, Zapata-Hernandez C, Santa-González GA, Uribe D, Saiz J, Buitrago-Sierra R, Tobón C. Characterization of airborne particulate matter and its toxic and proarrhythmic effects: A case study in Aburrá Valley, Colombia. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 336:122475. [PMID: 37652229 DOI: 10.1016/j.envpol.2023.122475] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 08/15/2023] [Accepted: 08/28/2023] [Indexed: 09/02/2023]
Abstract
Particle matter (PM) is a complex mixture of particles suspended in the air, mainly caused by fuel combustion from vehicles and industry, and has been related to pulmonary and cardiovascular diseases. The Metropolitan Area of Aburrá Valley in Colombia is the second most populous urban agglomeration in the country and the third densest in the world, composed of ten municipalities. Examining the physicochemical properties of PM is crucial in comprehending its composition and its effects on human health, as it varies based on the socioeconomic dynamics specific to each city. This study characterized the PM collected from the north, south, and central zones to evaluate its chemical composition and morphology. Different elements such as silicon, carbon, aluminum, potassium, calcium, sodium, iron, magnesium, and copper and the presence of unburned fuel, motor oil, and silicon fibers were identified. In vitro and in silico studies were conducted to evaluate the toxicity of the PM, and it was found that the PM collected from the central zone had the greatest impact on cell viability and caused DNA damage. The in silico study demonstrated that PM has concentration-dependent proarrhythmic effects, reflected in an action potential duration shortening and an increased number of reentries, which may contribute to the development of cardiac arrhythmias. Overall, the results suggest that the size and chemical composition of ambient PM can induce toxicity and play an important role in the generation of arrhythmias.
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Affiliation(s)
- Laura C Palacio
- MATBIOM, Facultad de Ciencias Básicas, Universidad de Medellín, Medellín, Colombia
| | - Geraldine Durango-Giraldo
- MATyER, Facultad de Ingeniería, Institución Universitaria ITM, Medellín, Colombia; Departament of Textile and Paper Engineering, Polytechnical University of Catalonia, Barcelona, Spain
| | - Camilo Zapata-Hernandez
- MATBIOM, Facultad de Ciencias Básicas, Universidad de Medellín, Medellín, Colombia; MATyER, Facultad de Ingeniería, Institución Universitaria ITM, Medellín, Colombia
| | - Gloria A Santa-González
- GI(2)B, Facultad de Ciencias Exactas y Aplicadas, Institución Universitaria ITM, Medellín, Colombia
| | - Diego Uribe
- GI(2)B, Facultad de Ciencias Exactas y Aplicadas, Institución Universitaria ITM, Medellín, Colombia
| | - Javier Saiz
- CI(2)B, Universitat Politècnica de València, Valencia, Spain
| | | | - Catalina Tobón
- MATBIOM, Facultad de Ciencias Básicas, Universidad de Medellín, Medellín, Colombia.
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Ishkaeva RA, Khaertdinov NN, Yakovlev AV, Esmeteva MV, Salakhieva DV, Nizamov IS, Sitdikova GF, Abdullin TI. Characterization of Glutathione Dithiophosphates as Long-Acting H 2S Donors. Int J Mol Sci 2023; 24:11063. [PMID: 37446245 DOI: 10.3390/ijms241311063] [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: 06/10/2023] [Revised: 06/28/2023] [Accepted: 06/30/2023] [Indexed: 07/15/2023] Open
Abstract
Considering the important cytoprotective and signaling roles but relatively narrow therapeutic index of hydrogen sulfide (H2S), advanced H2S donors are required to achieve a therapeutic effect. In this study, we proposed glutathione dithiophosphates as new combination donors of H2S and glutathione. The kinetics of H2S formation in dithiophosphate solutions suggested a continuous H2S release by the donors, which was higher for the dithiophosphate of reduced glutathione than oxidized glutathione. The compounds, unlike NaHS, inhibited the proliferation of C2C12 myoblasts at submillimolar concentrations due to an efficient increase in intracellular H2S. The H2S donors more profoundly affected reactive oxygen species and reduced glutathione levels in C2C12 myocytes, in which these parameters were elevated compared to myoblasts. Oxidized glutathione dithiophosphate as well as control donors exerted antioxidant action toward myocytes, whereas the effect of reduced glutathione dithiophosphate at (sub-)micromolar concentrations was rather modulating. This dithiophosphate showed an enhanced negative inotropic effect mediated by H2S upon contraction of the atrial myocardium, furthermore, its activity was prolonged and reluctant for washing. These findings identify glutathione dithiophosphates as redox-modulating H2S donors with long-acting profile, which are of interest for further pharmacological investigation.
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Affiliation(s)
- Rezeda A Ishkaeva
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
- Scientific and Educational Center of Pharmaceutics, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
| | - Nail N Khaertdinov
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
| | - Aleksey V Yakovlev
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
| | - Marina V Esmeteva
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
- Scientific and Educational Center of Pharmaceutics, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
| | - Diana V Salakhieva
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
- Scientific and Educational Center of Pharmaceutics, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
| | - Ilyas S Nizamov
- Alexander Butlerov Institute of Chemistry, Kazan (Volga Region) Federal University, 420008 Kazan, Russia
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center of RAS, 8 Arbuzov St., 420088 Kazan, Russia
| | - Guzel F Sitdikova
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
| | - Timur I Abdullin
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
- Scientific and Educational Center of Pharmaceutics, Kazan (Volga Region) Federal University, 18 Kremlyovskaya St., 420008 Kazan, Russia
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4
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Bigorra Mir M, Charlebois E, Tsyplenkova S, Fillebeen C, Pantopoulos K. Cardiac Hamp mRNA Is Predominantly Expressed in the Right Atrium and Does Not Respond to Iron. Int J Mol Sci 2023; 24:ijms24065163. [PMID: 36982241 PMCID: PMC10049151 DOI: 10.3390/ijms24065163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/03/2023] [Accepted: 03/06/2023] [Indexed: 03/10/2023] Open
Abstract
Hepcidin is a liver-derived hormone that controls systemic iron traffic. It is also expressed in the heart, where it acts locally. We utilized cell and mouse models to study the regulation, expression, and function of cardiac hepcidin. Hepcidin-encoding Hamp mRNA was induced upon differentiation of C2C12 cells to a cardiomyocyte-like phenotype and was not further stimulated by BMP6, BMP2, or IL-6, the major inducers of hepatic hepcidin. The mRNAs encoding hepcidin and its upstream regulator hemojuvelin (Hjv) are primarily expressed in the atria of the heart, with ~20-fold higher Hamp mRNA levels in the right vs. left atrium and negligible expression in the ventricles and apex. Hjv−/− mice, a model of hemochromatosis due to suppression of liver hepcidin, exhibit only modest cardiac Hamp deficiency and minor cardiac dysfunction. Dietary iron manipulations did not significantly affect cardiac Hamp mRNA in the atria of wild-type or Hjv−/− mice. Two weeks following myocardial infarction, Hamp was robustly induced in the liver and heart apex but not atria, possibly in response to inflammation. We conclude that cardiac Hamp is predominantly expressed in the right atrium and is partially regulated by Hjv; however, it does not respond to iron and other inducers of hepatic hepcidin.
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Affiliation(s)
- Maria Bigorra Mir
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC H3T 1E2, Canada
| | - Edouard Charlebois
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC H3T 1E2, Canada
| | - Sofiya Tsyplenkova
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC H3T 1E2, Canada
| | - Carine Fillebeen
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC H3T 1E2, Canada
| | - Kostas Pantopoulos
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, QC H3T 1E2, Canada
- Department of Medicine, McGill University, Montreal, QC H4A 3J1, Canada
- Correspondence: ; Tel.: +1-514-340-8260 (ext. 25293)
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Actin-microtubule cytoskeletal interplay mediated by MRTF-A/SRF signaling promotes dilated cardiomyopathy caused by LMNA mutations. Nat Commun 2022; 13:7886. [PMID: 36550158 PMCID: PMC9780334 DOI: 10.1038/s41467-022-35639-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/14/2022] [Indexed: 12/24/2022] Open
Abstract
Mutations in the lamin A/C gene (LMNA) cause dilated cardiomyopathy associated with increased activity of ERK1/2 in the heart. We recently showed that ERK1/2 phosphorylates cofilin-1 on threonine 25 (phospho(T25)-cofilin-1) that in turn disassembles the actin cytoskeleton. Here, we show that in muscle cells carrying a cardiomyopathy-causing LMNA mutation, phospho(T25)-cofilin-1 binds to myocardin-related transcription factor A (MRTF-A) in the cytoplasm, thus preventing the stimulation of serum response factor (SRF) in the nucleus. Inhibiting the MRTF-A/SRF axis leads to decreased α-tubulin acetylation by reducing the expression of ATAT1 gene encoding α-tubulin acetyltransferase 1. Hence, tubulin acetylation is decreased in cardiomyocytes derived from male patients with LMNA mutations and in heart and isolated cardiomyocytes from Lmnap.H222P/H222P male mice. In Atat1 knockout mice, deficient for acetylated α-tubulin, we observe left ventricular dilation and mislocalization of Connexin 43 (Cx43) in heart. Increasing α-tubulin acetylation levels in Lmnap.H222P/H222P mice with tubastatin A treatment restores the proper localization of Cx43 and improves cardiac function. In summary, we show for the first time an actin-microtubule cytoskeletal interplay mediated by cofilin-1 and MRTF-A/SRF, promoting the dilated cardiomyopathy caused by LMNA mutations. Our findings suggest that modulating α-tubulin acetylation levels is a feasible strategy for improving cardiac function.
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Imai R, Horita S, Ono Y, Hagihara K, Shimizu M, Maejima Y, Shimomura K. Goshajinkigan, a Traditional Japanese Medicine, Suppresses Voltage-Gated Sodium Channel Nav1.4 Currents in C2C12 Cells. Biores Open Access 2020; 9:116-120. [PMID: 32368413 PMCID: PMC7194311 DOI: 10.1089/biores.2019.0034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Goshajinkigan (GJG) is a traditional Japanese Kampo medicine used clinically to treat muscle pain in Japan. However, its underlying mechanism remains unclear. Since voltage-gated sodium channel (Nav) 1.4 is involved in skeletal muscle contraction, we investigated the possibility that GJG may affect Nav1.4 currents. By using an electrophysiological technique on skeletal muscle cell line C2C12, we found that GJG suppresses Nav1.4 currents in C2C12 cells. It is suggested that GJG may improve skeletal muscle stiffness or cramps by inhibiting abnormal Nav1.4 excitation. GJG may act as a Nav1.4 blocker and may be useful to treat muscle stiffness and clamps as well as easing the pain.
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Affiliation(s)
- Ryota Imai
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Shoichiro Horita
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Yuko Ono
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, Fukushima, Japan.,Department of Disaster and Emergency Medicine, Graduate School of Medicine, Kobe University, Kobe, Japan
| | - Keisuke Hagihara
- Department of Kampo Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Masaru Shimizu
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, Fukushima, Japan.,Department of Neurology, Matsumura General Hospital, Fukushima, Japan
| | - Yuko Maejima
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Kenju Shimomura
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, Fukushima, Japan
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7
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Hsu PL, Horng LY, Peng KY, Wu CL, Sung HC, Wu RT. Activation of mitochondrial function and Hb expression in non-haematopoietic cells by an EPO inducer ameliorates ischaemic diseases in mice. Br J Pharmacol 2014; 169:1461-76. [PMID: 23530756 DOI: 10.1111/bph.12197] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 01/31/2013] [Accepted: 02/04/2013] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND AND PURPOSE Many organs suffer from ischaemic injuries that reduce their ability to generate sufficient energy, which is required for functional maintenance and repair. Erythropoietin (EPO) ameliorates ischaemic injuries by pleiotropic effects. The aim of this study was to investigate the effect and mechanism of a small molecule EH-201, and found it as a potent EPO inducer and its effect in non-haematopoietic cells for therapeutic potential in ischemic disorders. EXPERIMENTAL APPROACH Mice kidney slices, primary hepatocytes, primary cardiomyocytes and C2C12 myoblasts were treated with EH-201. The effects of this treatment on EPO, Hb expression and mitochondrial biogenesis were analysed. In vivo, doxorubicin-induced cardiomyopathic mice were treated with EH-201. The mice were subjected to an endurance test, electrocardiography and echocardiography, and a histological examination of the isolated hearts was performed. EH-201 was also administered to cisplatin-induced nephropathic mice. KEY RESULTS In non-haematopoietic cells, EH-201 was potent at inducing EPO. EH-201 also stimulated mitochondrial biogenesis and enhanced the expression of Hb by a mechanism dependent on EPO-mediated signalling. In mechanistic studies, using EPO and EPO receptor-neutralizing antibodies, we confirmed that EH-201 enhances EPO-EPOR autocrine activity. EH-201 robustly increased the endurance performance activity of healthy and cardiomyopathic mice during hypoxic stress, enhanced myocardial mitochondrial biogenesis and Hb expression, and also improved cardiac function. EH-201 ameliorated anaemia and renal dysfunction in nephropathic mice. CONCLUSIONS AND IMPLICATIONS The enhancement and recovery of cellular functions through the stimulation of mitochondrial activity and Hb production in non-haematopoietic cells by an inducer of endogenous EPO has potential as a therapeutic strategy for ischaemic diseases.
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Affiliation(s)
- Pei-Lun Hsu
- Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei, Taiwan
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8
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Mike AK, Koenig X, Koley M, Heher P, Wahl G, Rubi L, Schnürch M, Mihovilovic MD, Weitzer G, Hilber K. Small molecule cardiogenol C upregulates cardiac markers and induces cardiac functional properties in lineage-committed progenitor cells. Cell Physiol Biochem 2014; 33:205-21. [PMID: 24481283 PMCID: PMC4389081 DOI: 10.1159/000356663] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2013] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND/AIMS Cell transplantation into the heart is a new therapy after myocardial infarction. Its success, however, is impeded by poor donor cell survival and by limited transdifferentiation of the transplanted cells into functional cardiomyocytes. A promising strategy to overcome these problems is the induction of cardiomyogenic properties in donor cells by small molecules. METHODS Here we studied cardiomyogenic effects of the small molecule compound cardiogenol C (CgC), and structural derivatives thereof, on lineage-committed progenitor cells by various molecular biological, biochemical, and functional assays. RESULTS Treatment with CgC up-regulated cardiac marker expression in skeletal myoblasts. Importantly, the compound also induced cardiac functional properties: first, cardiac-like sodium currents in skeletal myoblasts, and secondly, spontaneous contractions in cardiovascular progenitor cell-derived cardiac bodies. CONCLUSION CgC induces cardiomyogenic function in lineage-committed progenitor cells, and can thus be considered a promising tool to improve cardiac repair by cell therapy.
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Affiliation(s)
- Agnes K. Mike
- Center for Physiology and Pharmacology, Department of Neurophysiology and –Pharmacology, Medical University of Vienna
| | - Xaver Koenig
- Center for Physiology and Pharmacology, Department of Neurophysiology and –Pharmacology, Medical University of Vienna
| | - Moumita Koley
- Institute of Applied Synthetic Chemistry, Vienna University of Technology
| | - Philipp Heher
- Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Vienna, Austria
| | - Gerald Wahl
- Center for Physiology and Pharmacology, Department of Neurophysiology and –Pharmacology, Medical University of Vienna
| | - Lena Rubi
- Center for Physiology and Pharmacology, Department of Neurophysiology and –Pharmacology, Medical University of Vienna
| | - Michael Schnürch
- Institute of Applied Synthetic Chemistry, Vienna University of Technology
| | | | - Georg Weitzer
- Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Vienna, Austria
| | - Karlheinz Hilber
- Center for Physiology and Pharmacology, Department of Neurophysiology and –Pharmacology, Medical University of Vienna
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9
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Choi JC, Wu W, Muchir A, Iwata S, Homma S, Worman HJ. Dual specificity phosphatase 4 mediates cardiomyopathy caused by lamin A/C (LMNA) gene mutation. J Biol Chem 2012; 287:40513-24. [PMID: 23048029 DOI: 10.1074/jbc.m112.404541] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Mutations in LMNA gene cause cardiomyopathy, for which mechanistic insights are lacking. RESULTS Dusp4 expression is enhanced in hearts with LMNA cardiomyopathy, and its overexpression in mice causes it by activating AKT-mTOR signaling that impairs autophagy. CONCLUSIONS Dusp4 causes cardiac dysfunction and may contribute to the development of LMNA cardiomyopathy. SIGNIFICANCE Revealing pathogenic mechanisms of LMNA cardiomyopathy is essential for the development of mechanism-based therapies. Mutations in the lamin A/C gene (LMNA) cause a diverse spectrum of diseases, the most common of which is dilated cardiomyopathy often with skeletal muscular dystrophy. Lamin A and C are fundamental components of the nuclear lamina, a dynamic meshwork of intermediate filaments lining the nuclear envelope inner membrane. Prevailing evidence suggests that the nuclear envelope functions as a signaling node and that abnormality in the nuclear lamina leads to dysregulated signaling pathways that underlie disease pathogenesis. We previously showed that activated ERK1/2 in hearts of a mouse model of LMNA cardiomyopathy (Lmna(H222P/H222P) mice) contributes to disease, but the complete molecular pathogenesis remains poorly understood. Here we uncover a pathogenic role of dual specificity phosphatase 4 (Dusp4), which is transcriptionally induced by ERK1/2. Dusp4 is highly expressed in the hearts of Lmna(H222P/H222P) mice, and transgenic mice with cardiac-selective overexpression of Dusp4 display heart dysfunction similar to LMNA cardiomyopathy. In both primary tissue and cell culture models, overexpression of Dusp4 positively regulates AKT-mTOR signaling, resulting in impaired autophagy. These findings identify a pathogenic role of Dusp4 in LMNA cardiomyopathy.
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Affiliation(s)
- Jason C Choi
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
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10
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Hupkes M, Jonsson MKB, Scheenen WJ, van Rotterdam W, Sotoca AM, van Someren EP, van der Heyden MAG, van Veen TA, van Ravestein-van Os RI, Bauerschmidt S, Piek E, Ypey DL, van Zoelen EJ, Dechering KJ. Epigenetics: DNA demethylation promotes skeletal myotube maturation. FASEB J 2011; 25:3861-72. [PMID: 21795504 DOI: 10.1096/fj.11-186122] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Mesenchymal progenitor cells can be differentiated in vitro into myotubes that exhibit many characteristic features of primary mammalian skeletal muscle fibers. However, in general, they do not show the functional excitation-contraction coupling or the striated sarcomere arrangement typical of mature myofibers. Epigenetic modifications have been shown to play a key role in regulating the progressional changes in transcription necessary for muscle differentiation. In this study, we demonstrate that treatment of murine C2C12 mesenchymal progenitor cells with 10 μM of the DNA methylation inhibitor 5-azacytidine (5AC) promotes myogenesis, resulting in myotubes with enhanced maturity as compared to untreated myotubes. Specifically, 5AC treatment resulted in the up-regulation of muscle genes at the myoblast stage, while at later stages nearly 50% of the 5AC-treated myotubes displayed a mature, well-defined sarcomere organization, as well as spontaneous contractions that coincided with action potentials and intracellular calcium transients. Both the percentage of striated myotubes and their contractile activity could be inhibited by 20 nM TTX, 10 μM ryanodine, and 100 μM nifedipine, suggesting that action potential-induced calcium transients are responsible for these characteristics. Our data suggest that genomic demethylation induced by 5AC overcomes an epigenetic barrier that prevents untreated C2C12 myotubes from reaching full maturity.
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Affiliation(s)
- Marlinda Hupkes
- Department of Cell and Applied Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
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11
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Affiliation(s)
- Hung Q Ly
- Department of Medicine, Montreal Heart Institute, and Université de Montréal, Montréal, Quebec, Canada
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12
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Mille M, Koenig X, Zebedin E, Uhrin P, Cervenka R, Todt H, Hilber K. Sodium current properties of primary skeletal myocytes and cardiomyocytes derived from different mouse strains. Pflugers Arch 2008; 457:1023-33. [PMID: 18704489 DOI: 10.1007/s00424-008-0570-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Revised: 07/25/2008] [Accepted: 07/30/2008] [Indexed: 10/21/2022]
Abstract
The mouse has become the preferred animal for genetic manipulations. Because of the diverse genetic backgrounds of various mouse strains, these can manifest strikingly different characteristics. Here, we studied the functional properties of currents through voltage-gated sodium channels in primary cultures of skeletal myocytes and cardiomyocytes derived from the three commonly used mouse strains BL6, 129/Sv, and FVB, by using the whole-cell patch-clamp technique. We found strain-specific sodium current function in skeletal myocytes, which could partly be explained by differences in sodium channel isoform expression. In addition, we found significant effects of cell source (neonatal or adult animal-derived) and variation of the differentiation time period. In contrast to skeletal myocytes, sodium current function in cardiomyocytes was similar in all strains. Our findings are relevant for the design and proper interpretation of electrophysiological studies, which use excitable cells in primary culture as a model system.
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Affiliation(s)
- M Mille
- Institute of Pharmacology, Center for Biomolecular Medicine and Pharmacology, Medical University of Vienna, Austria
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13
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Biochemical constitution of extracellular medium is critical for control of human breast cancer MDA-MB-231 cell motility. J Membr Biol 2008; 223:27-36. [PMID: 18575796 DOI: 10.1007/s00232-008-9110-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2007] [Accepted: 05/07/2008] [Indexed: 01/04/2023]
Abstract
Although voltage-gated sodium channel (VGSC) activity, upregulated significantly in strongly metastatic human breast cancer cells, has been found to potentiate a variety of in vitro metastatic cell behaviors, the mechanism(s) regulating channel expression/activity is not clear. As a step toward identifying possible serum factors that might be responsible for this, we tested whether medium in which fetal bovine serum (FBS) was substituted with a commercial serum replacement agent (SR-2), comprising insulin and bovine serum albumin, would influence the VGSC-dependent in vitro metastatic cell behaviors. Human breast cancer MDA-MB-231 cells were used as a model. Measurements of lateral motility, transverse migration and adhesion showed consistently that the channel's involvement in metastatic cell behaviors depended on the extracellular biochemical conditions. In normal medium (5% FBS), tetrodotoxin (TTX), a highly specific blocker of VGSCs, suppressed these cellular behaviors, as reported before. In contrast, in SR-2 medium, TTX had opposite effects. However, blocking endogenous insulin/insulin-like growth factor receptor signaling with AG1024 eliminated or reversed the anomalous effects of TTX. Insulin added to serum-free medium increased migration, and TTX increased it further. In conclusion, (1) the biochemical constitution of the extracellular medium had a significant impact upon breast cancer cells' in vitro metastatic behaviors and (2) insulin, in particular, controlled the mode of the functional association between cells' VGSC activity and metastatic machinery.
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14
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Hilber K. Skeletal myocyte plasticity: basis for improved therapeutic potential? Curr Opin Pharmacol 2008; 8:327-32. [PMID: 18329336 DOI: 10.1016/j.coph.2008.01.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2007] [Revised: 01/18/2008] [Accepted: 01/25/2008] [Indexed: 12/25/2022]
Abstract
Skeletal muscle tissue exhibits a remarkable capacity to regenerate after injury and to adapt its properties in response to altered functional demands or environmental pressure. This potential renders skeletal myocytes especially attractive candidates to be used in therapeutic strategies. Besides the well-described adaptability of skeletal myocytes in terms of contractile function and metabolic profile, more recent research has revealed that the electrophysiological properties of myocytes are also subject to significant changes both under physiological conditions and in pathophysiological situations. A better understanding of skeletal myocyte plasticity, its regulation and its forced induction could improve existing therapeutic approaches and may pave the way for new therapeutic strategies.
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Affiliation(s)
- Karlheinz Hilber
- Center of Biomolecular Medicine and Pharmacology, Institute of Pharmacology, Medical University of Vienna, Waehringerstrasse 13A, 1090 Vienna, Austria.
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15
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Zebedin E, Koenig X, Radenkovic M, Pankevych H, Todt H, Freissmuth M, Hilber K. Effects of duramycin on cardiac voltage-gated ion channels. Naunyn Schmiedebergs Arch Pharmacol 2008; 377:87-100. [DOI: 10.1007/s00210-007-0248-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Accepted: 12/07/2007] [Indexed: 11/28/2022]
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