Ivar Sjaastad

• Barth, Zoltan; Schwartz, Thomas; Flatø, Berit; Aaløkken, Trond Mogens; Koller, Akos; Lund, May-Brith; Sjaastad, Ivar & Sanner, Helga (2019). The association between nailfold capillary density and pulmonary and cardiac involvement in medium-to long-standing juvenile dermatomyositis. Arthritis care & research.  ISSN 2151-464X.  71(4), s 492- 497 . doi: 10.1002/acr.23687
• Berntsen, Kristin Schjander; Edvardsen, Elisabeth; Hansen, Bjørge Hermann; Flatø, Berit; Sjaastad, Ivar & Sanner, Helga (2019). Cardiorespiratory fitness in long-term juvenile dermatomyositis: A controlled, cross-sectional study of active/inactive disease. Rheumatology.  ISSN 1462-0324.  58(3), s 492- 501 . doi: 10.1093/rheumatology/key342 Vis sammendrag

  Objectives. To compare cardiorespiratory fitness (CRF) expressed as maximal oxygen uptake (VO2max) between patients with long-term JDM and controls and between patients with active and inactive disease, as well as to explore exercise limiting factors and associations between CRF and disease variables. Methods. JDM patients (n=45) and age- and gender-matched controls (n=45) performed a cardiopulmonary exercise test (CPET) on a treadmill until exhaustion. Physical activity was measured by accelerometers. Disease activity, damage and muscle strength/function were assessed by validated tools. Clinically inactive disease was defined according to PRINTO criteria. Results. The mean disease duration was 20.8 (S.D. 11.9) years and 29/45 (64%) patients had inactive disease. A low VO2max was found in 27% of patients vs 4% of controls (P = 0.006). The mean VO2max and maximal ventilation (VEmax) were lower in patients with active and inactive disease compared with controls. Patients with active disease also had lower maximal voluntary ventilation (MVV) compared with controls and lower VEmax and MVV compared with those with inactive disease. Patients with inactive disease had lower physical activity levels compared with controls. VO2max correlated negatively with disease damage in patients with inactive disease and positively with muscle strength/function in patients with active disease. Conclusion. CRF was lower in JDM patients, both with active and inactive disease, compared with controls after a mean 20 years disease duration. Cardiopulmonary exercise test results suggested different limiting factors contributing to the reduced CRF according to disease activity, including deconditioning in inactive disease and reduced ventilatory capacity in active disease. Further research is needed to verify this.

• Berntsen, Kristin Schjander; Raastad, Truls; Marstein, Henriette; Kirkhus, Eva Astrid; Merckoll, Else; Cumming, Kristoffer Toldnes; Flatø, Berit; Sjaastad, Ivar & Sanner, Helga (2019). Functional and Structural Adaptations of Skeletal Muscle in Long-Term Juvenile Dermatomyositis; a Controlled Cross-Sectional Study. Arthritis & Rheumatology.  ISSN 2326-5191. . doi: 10.1002/art.41174
• Blom, Kjersti Benedicte; Bergo, Kaja Knudsen; Espe, Emil Knut Stenersen; Rosseland, Vigdis; Grøtta, Ole Jørgen; Mjøen, Geir; Åsberg, Anders; Bergan, Stein; Sanner, Helga; Bergersen, Tone Kristin; Bjørnerheim, Reidar; Skauby, Morten Heier; Seljeflot, Ingebjørg; Waldum-Grevbo, Bård; Dahle, Dag Olav; Sjaastad, Ivar & Birkeland, Jon Arne (2019). Cardiovascular rEmodelling in living kidNey donorS with reduced glomerular filtration rate: rationale and design of the CENS study. Blood Pressure.  ISSN 0803-7051.  s 1- 13 . doi: 10.1080/08037051.2019.1684817
• Espe, Emil Knut Stenersen; Aronsen, Jan Magnus; Norden, Einar Sjaastad; Zhang, Lili & Sjaastad, Ivar (2019). Regional right ventricular function in rats: a novel magnetic resonance imaging method for measurement of right ventricular strain. American Journal of Physiology. Heart and Circulatory Physiology.  ISSN 0363-6135.  318(1), s 143- 153 . doi: 10.1152/ajpheart.00357.2019
• Lipsett, David Bruce; Frisk, Michael; Aronsen, Jan Magnus; Norden, Einar Sjaastad; Buonarati, Olivia R.; Cataliotti, Alessandro; Hell, Johannes W.; Sjaastad, Ivar; Christensen, Geir Arve & Louch, William Edward (2019). Cardiomyocyte substructure reverts to an immature phenotype during heart failure. Journal of Physiology.  ISSN 0022-3751.  597(7), s 1833- 1853 . doi: 10.1113/JP277273
• Marstein, Henriette; Schwartz, Thomas; Aaløkken, Trond M; Lund, May-Brith; Flatø, Berit; Sjaastad, Ivar & Sanner, Helga (2019). Novel associations between cytokines and pulmonary involvement in juvenile dermatomyositis - a cross-sectional study of long-term disease. Rheumatology.  ISSN 1462-0324.  2019;0 . doi: 10.1093/rheumatology/kez531
• Mathiesen, Sabrina Bech; Lunde, Marianne; Aronsen, Jan Magnus; Romaine, Andreas; Kaupang, Anita; Martinsen, Marita; De Souza, Gustavo Antonio; Nyman, Tuula Anneli; Sjaastad, Ivar; Christensen, Geir Arve & Carlson, Cathrine Rein (2019). The cardiac syndecan-4 interactome reveals a role for syndecan-4 in nuclear translocation of muscle LIM protein (MLP). Journal of Biological Chemistry.  ISSN 0021-9258.  294(22), s 8717- 8731 . doi: 10.1074/jbc.RA118.006423 Vis sammendrag

  Costameres are signaling hubs at the sarcolemma and important contact points between the extracellular matrix and cell interior, sensing and transducing biomechanical signals into a cellular response. The transmembrane proteoglycan syndecan-4 localizes to these attachment points and has been shown to be important in the initial stages of cardiac remodeling, but its mechanistic function in the heart remains insufficiently understood. Here, we sought to map the cardiac interactome of syndecan-4 to better understand its function and downstream signaling mechanisms. By combining two different affinity purification methods with MS analysis, we found that the cardiac syndecan-4 interactome consists of 21 novel and 29 previously described interaction partners. Nine of the novel partners were further validated to bind syndecan-4 in HEK293 cells (i.e. CAVIN1/PTRF, CCT5, CDK9, EIF2S1, EIF4B, MPP7, PARVB, PFKM, and RASIP). We also found that 19 of the 50 interactome partners bind differently to syndecan-4 in the left ventricle lysate from aortic-banded heart failure (ABHF) rats compared with SHAM-operated animals. One of these partners was the well-known mechanotransducer muscle LIM protein (MLP), which showed direct and increased binding to syndecan-4 in ABHF. Nuclear translocation is important in MLP-mediated signaling, and we found less MLP in the nuclear-enriched fractions from syndecan-4-/- mouse left ventricles but increased nuclear MLP when syndecan-4 was overexpressed in a cardiomyocyte cell line. In the presence of a cell-permeable syndecan-4-MLP disruptor peptide, the nuclear MLP level was reduced. These findings suggest that syndecan-4 mediates nuclear translocation of MLP in the heart

• Mcginley, Gary George; Bendiksen, Bård Andre; Zhang, Lili; Aronsen, Jan Magnus; Norden, Einar Sjaastad; Sjaastad, Ivar & Espe, Emil Knut Stenersen (2019). Accelerated magnetic resonance imaging tissue phase mapping of the rat myocardium using compressed sensing with iterative soft-thresholding. PLOS ONE.  ISSN 1932-6203.  14:e0218874(7), s 1- 17 . doi: 10.1371/journal.pone.0218874
• Mohammadzadeh, Naiyereh; Lunde, Ida Gjervold; Andenæs, Kine; Strand, Mari Elen; Aronsen, Jan Magnus; Skrbic, Biljana; Marstein, Henriette; Bandlien, Caroline; Nygård, Ståle; Gorham, Joshua; Sjaastad, Ivar; Chakravarti, Shukti; Christensen, Geir Arve; Engebretsen, Kristin V Thunheim & Tønnessen, Theis (2019). The extracellular matrix proteoglycan lumican improves survival and counteracts cardiac dilatation and failure in mice subjected to pressure overload. Scientific Reports.  ISSN 2045-2322.  9:9206, s 1- 13 . doi: 10.1038/s41598-019-45651-9
• NOMELAND, BIRGIT; Hetlevik, Siri Opsahl; Sanner, Helga; Barth, Zoltan; Schwartz, Thomas; Flatø, Berit; Lilleby, Vibke & Sjaastad, Ivar (2019). Cardiac function is impaired in longstanding juvenile-onset mixed connective tissue disease - a controlled study. Journal of Rheumatology.  ISSN 0315-162X.  46(7), s 1- 10 . doi: 10.3899/jrheum.180526
• NOMELAND, BIRGIT; Hetlevik, Siri Opsahl; Sanner, Helga; Barth, Zoltan; Schwartz, Thomas; Flatø, Berit; Lilleby, Vibke & Sjaastad, Ivar (2019). Effect on cardiac function of longstanding juvenile-onset mixed connective tissue disease: A controlled study. Journal of Rheumatology.  ISSN 0315-162X.  46(7), s 739- 747 . doi: 10.3899/jrheum.180526
• Ottesen, Anett Hellebø; Carlson, Cathrine Rein; Eken, Olav Søvik; Sadredini, Mani; Myhre, Peder Langeland; Shen, Xin; Dalhus, Bjørn; Laver, Derek R.; Lunde, Per Kristian; Kurola, Jouni; Lunde, Marianne; Hoff, Jon Erik; Godang, Kristin; Sjaastad, Ivar; Pettilä, Ville; Stridsberg, Mats; Lehnart, Stephan E.; Edwards, Andrew; Lunde, Ida Gjervold; Omland, Torbjørn; Stokke, Mathis Korseberg; Christensen, Geir Arve; Røsjø, Helge & Louch, William Edward (2019). Secretoneurin Is an Endogenous Calcium/Calmodulin-Dependent Protein Kinase II Inhibitor That Attenuates Ca2+-Dependent Arrhythmia. Circulation: Arrhythmia and Electrophysiology.  ISSN 1941-3149.  12(4) . doi: 10.1161/CIRCEP.118.007045 Fulltekst i vitenarkiv.
• Røe, Åsmund Treu; Ruud, Marianne; Espe, Emil Knut Stenersen; Manfra, Ornella; Longobardi, S; Aronsen, Jan Magnus; Norden, Einar Sjaastad; Husebye, T.; Kolstad, Terje R Selnes; Cataliotti, Alessandro; Christensen, Geir Arve; Sejersted, Ole M; Niederer, Steven A.; Andersen, Geir Øystein; Sjaastad, Ivar & Louch, William Edward (2019). Regional diastolic dysfunction in post-infarction heart failure: role of local mechanical load and SERCA expression. Cardiovascular Research (CVR).  ISSN 0008-6363.  115(4), s 752- 764 . doi: 10.1093/cvr/cvy257
• Skogestad, Jonas; Aronsen, Jan Magnus; Tovsrud, Nils; Wanichawan, Pimthanya; Hougen, Karina; Stokke, Mathis Korseberg; Carlson, Cathrine Rein; Sjaastad, Ivar; Sejersted, Ole M & Swift, Fredrik (2019). Coupling of the Na+/K+-ATPase to Ankyrin B controls Na+/Ca2+ exchanger activity in cardiomyocytes. Cardiovascular Research (CVR).  ISSN 0008-6363. . doi: 10.1093/cvr/cvz087
• Skogestad, Jonas; Lines, Glenn; Louch, William Edward; Sejersted, Ole M; Sjaastad, Ivar & Aronsen, Jan Magnus (2019). Evidence for heterogeneous subsarcolemmal Na+ Levels in rat ventricular myocytes. American Journal of Physiology. Heart and Circulatory Physiology.  ISSN 0363-6135.  316(5) . doi: 10.1152/ajpheart.00637.2018
• Sokolova, Marina; Sjaastad, Ivar; Louwe, Maria Cornelia; Alfsnes, Katrine; Aronsen, Jan Magnus; Zhang, Lili; Haugstad, Solveig Bjærum; Bendiksen, Bård Andre; Øgaard, Jonas; Bliksøen, Marte; Lien, Egil; Berge, Rolf Kristian; Aukrust, Pål; Ranheim, Trine & Yndestad, Arne (2019). NLRP3 inflammasome promotes myocardial remodeling during diet-induced obesity. Frontiers in Immunology.  ISSN 1664-3224.  10:1621(JULY), s 1- 13 . doi: 10.3389/fimmu.2019.01621 Fulltekst i vitenarkiv.
• Udjus, Camilla; Fadila, Cero; Halvorsen, Bente; Behmen, Dina; Carlson, Cathrine Rein; Bendiksen, Bård Andre; Espe, Emil Knut Stenersen; Sjaastad, Ivar; Løberg, Else Marit; Yndestad, Arne; Aukrust, Pål; Christensen, Geir Arve; Skjønsberg, Ole Henning & Larsen, Karl-Otto (2019). Caspase-1 induces smooth muscle cell growth in hypoxia-induced pulmonary hypertension. American Journal of Physiology - Lung cellular and Molecular Physiology.  ISSN 1040-0605.  316(6), s L999- L1012 . doi: 10.1152/ajplung.00322.2018
• Andenæs, Kine; Lunde, Ida Gjervold; Mohammadzadeh, Naiyereh; Dahl, Christen Peder; Aronsen, Jan Magnus; Strand, Mari Elen; Palmero, Sheryl; Sjaastad, Ivar; Christensen, Geir Arve; Engebretsen, Kristin V Thunheim & Tønnessen, Theis (2018). The extracellular matrix proteoglycan fibromodulin is upregulated in clinical and experimental heart failure and affects cardiac remodeling. PLOS ONE.  ISSN 1932-6203.  13(7), s 1- 20 . doi: 10.1371/journal.pone.0201422 Fulltekst i vitenarkiv.
• Barth, Zoltan; NOMELAND, BIRGIT; Flatø, Berit; Koller, Akos; Sjaastad, Ivar & Sanner, Helga (2018). Assessment of Microvascular Abnormalities by Nailfold Capillaroscopy in Juvenile Dermatomyositis After Medium- to Long-Term Followup. Arthritis care & research.  ISSN 2151-464X.  70(5), s 768- 776 . doi: 10.1002/acr.23338
• Danielsen, Tore Kristian; Manotheepan, Ravinea; Sadredini, Mani; Leren, Ida Skrinde; Edwards, Andrew; Vincent, Kevin P.; Lehnart, Stephan .; Sejersted, Ole M; Sjaastad, Ivar; Haugaa, Kristina & Stokke, Mathis Korseberg (2018). Arrhythmia initiation in catecholaminergic polymorphic ventricular tachycardia type 1 depends on both heart rate and sympathetic stimulation. PLOS ONE.  ISSN 1932-6203.  13:e0207100(11), s 1- 21 . doi: 10.1371/journal.pone.0207100 Fulltekst i vitenarkiv.
• Kolstad, Terje R Selnes; Brink, Jonas van Den; Macquaide, Niall; Lunde, Per Kristian; Frisk, Michael; Aronsen, Jan Magnus; Norden, Einar Sjaastad; Cataliotti, Alessandro; Sjaastad, Ivar; Sejersted, Ole M; Edwards, Andrew; Lines, Glenn Terje & Louch, William Edward (2018). Ryanodine receptor dispersion disrupts Ca2+ release in failing cardiac myocytes. eLIFE.  ISSN 2050-084X.  7 . doi: 10.7554/eLife.39427 Fulltekst i vitenarkiv.
• Melleby, Arne Olav; Romaine, Andreas; Aronsen, Jan Magnus; Veras, Ioanni; Zhang, Lili; Sjaastad, Ivar; Lunde, Ida Gjervold & Christensen, Geir Arve (2018). A novel method for high precision aortic constriction that allows for generation of specific cardiac phenotypes in mice. Cardiovascular Research (CVR).  ISSN 0008-6363. . doi: 10.1093/cvr/cvy141
• Aronsen, Jan Magnus; Espe, Emil Knut Stenersen; Young-Halvorsen, Kristine Skårdal; Hasic, Almira; Zhang, Lili & Sjaastad, Ivar (2017). Noninvasive stratification of postinfarction rats based on the degree of cardiac dysfunction using magnetic resonance imaging and echocardiography. American Journal of Physiology. Heart and Circulatory Physiology.  ISSN 0363-6135.  312(5), s H932- H942 . doi: 10.1152/ajpheart.00668.2016
• Barth, Zoltan; Witzcak, Birgit; Flatø, Berit; Koller, Akos; Sjaastad, Ivar & Sanner, Helga (2017). Microvascular Abnormalities Assessed by Nailfold Capillaroscopy In Juvenile Dermatomyositis After Medium to Long-Term Follow-Up. Arthritis Care and Research.  ISSN 0893-7524. . doi: 10.1002/acr.23338
• Berntsen, Kristin Schjander; Tollisen, Anita; Schwartz, Thomas; Kirkhus, Eva; Aaløkken, Trond Mogens; Samersaw-Lund, May Brit; Flatø, Berit; Sjaastad, Ivar & Sanner, Helga (2017). Submaximal exercise capacity in juvenile dermatomyositis after longterm disease: The contribution of muscle, lung, and heart involvement. Journal of Rheumatology.  ISSN 0315-162X.  44(6), s 827- 834 . doi: 10.3899/jrheum.160997
• Dhondup, Yangchen; Sjaastad, Ivar; Sandanger, Øystein; Aronsen, Jan Magnus; Ahmed, Muhammad Shakil; Attramadal, Håvard; Finsen, Alexandra; Zhang, Lili; Ranheim, Trine; Alfsnes, Katrine; Aukrust, Pål; Christensen, Geir Arve; Yndestad, Arne & Vinge, Leif Erik (2017). Toll-like receptor 9 promotes survival in SERCA2a KO heart failure mice. Mediators of Inflammation.  ISSN 0962-9351.  2017:9450439, s 1- 11 . doi: 10.1155/2017/9450439 Fulltekst i vitenarkiv.
• Espe, Emil Knut Stenersen; Aronsen, Jan Magnus; Eriksen, Morten; Sejersted, Ole M; Zhang, Lili & Sjaastad, Ivar (2017). Regional dysfunction after myocardial infarction in rats. Circulation Cardiovascular Imaging.  ISSN 1941-9651.  10(9), s e005997 . doi: 10.1161/CIRCIMAGING.116.005997
• Espe, Emil Knut Stenersen; Young-Halvorsen, Kristine Skårdal; Aronsen, Jan Magnus; Zhang, Lili & Sjaastad, Ivar (2017). A semiautomatic method for rapid segmentation of velocity-encoded myocardial magnetic resonance imaging data. Magnetic Resonance in Medicine.  ISSN 0740-3194.  78(3), s 1199- 1207 . doi: 10.1002/mrm.26486
• Gattoni, Sara; Røe, Åsmund Treu; Aronsen, Jan Magnus; Sjaastad, Ivar; Louch, William Edward; Smith, Nicolas P. & Niederer, Steven A. (2017). Compensatory and decompensatory alterations in cardiomyocyte Ca2+ dynamics in hearts with diastolic dysfunction following aortic banding. Journal of Physiology.  ISSN 0022-3751.  595(12), s 3867- 3889 . doi: 10.1113/JP273879
• Johansen, Ida Beitnes; Sandblom, Erik; Skov, Peter V.; Gräns, Albin; Ekström, Andreas; Lunde, Ida Gjervold; Vindas, Marco Antonio; Zhang, Lili; Höglund, Erik; Frisk, Michael; Sjaastad, Ivar; Nilsson, Göran Erik & Øverli, Øyvind (2017). Bigger is not better: cortisol-induced cardiac growth and dysfunction in salmonids. Journal of Experimental Biology.  ISSN 0022-0949.  220(14), s 2545- 2553 . doi: 10.1242/jeb.135046 Fulltekst i vitenarkiv.
• Landfors, Miriam; Johansen, Jostein; Aronsen, Jan Magnus; Vågbø, Cathrine Broberg; Doré, Louis C.; He, Chuan; Sjaastad, Ivar; Sætrom, Pål; Fedorcsák, Péter; Dahl, John Arne; Aanes, Håvard; Fusser, Markus & Klungland, Arne (2017). Genome-wide profiling of DNA 5-hydroxymethylcytosine during rat Sertoli cell maturation. Cell Discovery.  ISSN 2056-5968.  3 . doi: 10.1038/celldisc.2017.13 Fulltekst i vitenarkiv.
• MANNER, INGJERD W; Waldum-Grevbo, Bård Endre; NOMELAND, BIRGIT; Bækken, Morten; Øktedalen, Olav; Os, Ingrid; Schwartz, Thomas & Sjaastad, Ivar (2017). Immune markers, diurnal blood pressure profile and cardiac function in virologically suppressed HIV-infected patients. Blood Pressure.  ISSN 0803-7051.  26(6), s 332- 340 . doi: 10.1080/08037051.2017.1346459
• Meier, Silja; Andressen, Kjetil Wessel; Aronsen, Jan Magnus; Sjaastad, Ivar; Hougen, Karina; Skomedal, Tor; Osnes, Jan-Bjørn; Qvigstad, Eirik; Levy, Finn Olav & Moltzau, Lise Roman (2017). PDE3 inhibition by C-type natriuretic peptide-induced cGMP enhances cAMP-mediated signaling in both non-failing and failing hearts. European Journal of Pharmacology.  ISSN 0014-2999.  812, s 174- 183 . doi: 10.1016/j.ejphar.2017.07.014
• Olsen, Maria Belland; Hildrestrand, Gunn Annette; Scheffler, Katja; Vinge, Leif Erik; Alfsnes, Katrine; Palibrk, Vuk; Wang, Junbai; Neurauter, Christine Gran; Gomez, Luisa Fernanda Luna; Johansen, Jostein; Øgaard, Jonas; Ohm, Ingrid Kristine; Slupphaug, Geir; Kusnierczyk, Anna; Fiane, Arnt E; Brorson, Sverre Henning; Zhang, Lili; Gullestad, Lars; Louch, William Edward; Iversen, Per Ole; Østlie, Ingunn; Klungland, Arne; Christensen, Geir Arve; Sjaastad, Ivar; Sætrom, Pål; Yndestad, Arne; Aukrust, Pål; Bjørås, Magnar & Finsen, Alexandra (2017). NEIL3-Dependent Regulation of Cardiac Fibroblast Proliferation Prevents Myocardial Rupture. Cell reports.  ISSN 2211-1247.  18, s 82- 92 . doi: 10.1016/j.celrep.2016.12.009 Fulltekst i vitenarkiv.
• Ottesen, Anett Hellebø; Carlson, Cathrine Rein; Louch, William Edward; Dahl, Mai Britt; Sandbu, Ragnhild Askeland; Johansen, Rune Forstrøm; Jarstadmarken, Hilde; Bjørås, Magnar; Høiseth, Arne Didrik; Brynildsen, Jon; Sjaastad, Ivar; Stridsberg, Mats; Omland, Torbjørn; Christensen, Geir Arve & Røsjø, Helge (2017). Glycosylated Chromogranin A in Heart Failure: Implications for Processing and Cardiomyocyte Calcium Homeostasis. Circulation: Heart Failure.  ISSN 1941-3289.  10(2) . doi: 10.1161/CIRCHEARTFAILURE.116.003675
• Romaine, Andreas; Sørensen, Ida Wiig; Zeltz, Cedric; Lu, Ning; Erusappan, Pugazendhi Murugan; Melleby, Arne Olav; Zhang, Lili; Bendiksen, Bård Andre; Robinson, EL; Aronsen, Jan Magnus; Herum, Kate Louise Møller; Danielsen, Håvard Emil; Sjaastad, Ivar; Christensen, Geir Arve & Gullberg, Donald (2017). Overexpression of integrin α11 induces cardiac fibrosis in mice. Acta Physiologica Scandinavica.  ISSN 0001-6772.  222:e13025(2), s 1- 17 . doi: 10.1111/apha.12932
• Røe, Åsmund Treu; Aronsen, Jan Magnus; Young-Halvorsen, Kristine Skårdal; Hamdani, Nazha; Linke, Wolfgang A.; Danielsen, Håvard Emil; Sejersted, Ole M; Sjaastad, Ivar & Louch, William Edward (2017). Increased passive stiffness promotes diastolic dysfunction despite improved Ca2+ handling during left ventricular concentric hypertrophy. Cardiovascular Research (CVR).  ISSN 0008-6363.  113(10), s 1161- 1172 . doi: 10.1093/cvr/cvx087
• Røe, Åsmund Treu; Sjaastad, Ivar & Louch, William Edward (2017). Hjertesvikt med bevart ejeksjonsfraksjon [Heart failure with preserved ejection fraction]. Tidsskrift for Den norske legeforening.  ISSN 0029-2001.  137(18), s 1- 8 . doi: 10.4045/tidsskr.16.1068
• Thienpont, Bernard; Aronsen, Jan Magnus; Robinson, Emma Louise; Okkenhaug, Hanneke; Loche, Elena; Ferrini, Arianna; Brien, Patrick; Alkass, Kanar; Tomasso, Antonio; Agrawal, Asmita; Bergmann, Olaf; Sjaastad, Ivar; Wolf, Reik & Roderick, Hywel Llewelyn (2017). The H3K9 dimethyltransferases EHMT1/2 protect against pathological cardiac hypertrophy. Journal of Clinical Investigation.  ISSN 0021-9738.  127(1), s 335- 348 . doi: 10.1172/JCI88353
• Aronsen, Jan Magnus; Louch, William Edward & Sjaastad, Ivar (2016). Cardiomyocyte Ca2+ dynamics: Clinical perspectives. Scandinavian Cardiovascular Journal.  ISSN 1401-7431.  50(2), s 65- 77 . doi: 10.3109/14017431.2015.1136079
• Barth, Zoltan; NOMELAND, BIRGIT; Schwartz, Thomas; Gjesdal, Knut; Flatø, Berit; Koller, Akos; Sanner, Helga & Sjaastad, Ivar (2016). In juvenile dermatomyositis, heart rate variability is reduced, and associated with both cardiac dysfunction and markers of inflammation: a cross-sectional study median 13.5 years after symptom onset. Rheumatology.  ISSN 1462-0324.  55(3), s 535- 543 . doi: 10.1093/rheumatology/kev376 Vis sammendrag

  Objectives. Low heart rate variability (HRV) is a well-established predictor of cardiac death. The aim of this study was to investigate arrhythmias and HRV in patients with JDM, and associations between HRV and inflammatory markers, echocardiographic measurements and disease parameters. Methods. Fifty-five patients with JDM were examined 2–34 years (median 13.5 years) after disease onset, and compared with 55 age and sex matched controls. Holter ECG monitoring and echocardiography were analysed blinded to patient information. Arrhythmia and HRV (six parameters) were analysed by standard software, finally adjudicated by an experienced cardiologist. Markers of inflammation (ESR, high sensitivity (hs)CRP and cytokines) were analysed. Disease activity and organ damage were assessed by clinical examination at follow-up and retrospectively by chart review. Results. In two out of six HRV parameters, JDM patients had lower values than controls. No difference in arrhythmias was found between the groups. In patients, but not in controls, there were significant negative correlations between five out of six HRV parameters, and ESR and hsCRP (Spearman correlation coefficient, −0.306 to −0.470; P, 0.023 to <0.001). Also, in patients, negative correlations were found between three out of six HRV parameters and systolic and diastolic function. Active disease and low HRV were associated. Patients with hsCRP in the highest quartile (Q4) had lower HRV in all parameters compared with those in pooled Q1–3 (P < 0.001). Conclusion. JDM patients had reduced HRV, which was associated with elevated inflammatory markers, active disease and reduced myocardial function. This suggests reduced vagal control of the heart; further studies are needed to determine whether this is also associated with cardiac morbidity or mortality.

• Dhondup, Yangchen; Ueland, Thor; Dahl, Christen Peder; Askevold, Erik Tandberg; Sandanger, Øystein; Fiane, Arnt E; Ohm, Ingrid Kristine; Sjaastad, Ivar; Finsen, Alexandra; Wæhre, Anne; Gullestad, Lars; Aukrust, Pål; Yndestad, Arne & Vinge, Leif Erik (2016). Low circulating levels of mitochondrial and high levels of nuclear DNA predict mortality in chronic heart failure. Journal of Cardiac Failure.  ISSN 1071-9164.  22(10), s 823- 828 . doi: 10.1016/j.cardfail.2016.06.013 Vis sammendrag

  Background Mitochondrial DNA (mtDNA) and possibly nuclear DNA (nDNA) are released as danger-associated molecular patterns during cardiac stress, and may activate several innate immune receptors. The purpose of this study was to investigate the regulation of these danger-associated molecular patterns during human heart failure (HF). Methods and Results Plasma levels of mtDNA and nDNA from HF patients (n = 84) were analyzed by reverse transcriptase-polymerase chain reaction and compared with controls (n = 72). Increased levels of mtDNA were found in New York Heart Association (NYHA) I-II and NYHA III-IV. There was evidence of increased nDNA in NYHA III-IV compared with controls and NYHA I-II. Kaplan-Meier analysis revealed higher mortality in patients with high nDNA levels, whereas high levels of mtDNA were associated with survival. Conclusions Plasma levels of mtDNA and nDNA are elevated in human HF associated with increased and decreased mortality, respectively. This study may suggest a rationale for exploring interventions within inflammatory signaling pathways activated by nucleic acids as novel targets in treatment of HF.

• Frisk, Michael; Ruud, Marianne; Espe, Emil Knut Stenersen; Aronsen, Jan Magnus; Røe, Åsmund Treu; Zhang, Lili; Norseng, Per Andreas; Sejersted, Ole M; Christensen, Geir Arve; Sjaastad, Ivar & Louch, William Edward (2016). Elevated ventricular wall stress disrupts cardiomyocyte t-tubule structure and calcium homeostasis. Cardiovascular Research (CVR).  ISSN 0008-6363. . doi: 10.1093/cw111
• Hafver, Tandekile Lubelwana; Hodne, Kjetil; Wanichawan, Pimthanya; Aronsen, Jan Magnus; Dalhus, Bjørn; Lunde, Per Kristian; Lunde, Marianne; Martinsen, Marita; Enger, Ulla Helene; Fuller, William; Sjaastad, Ivar; Louch, William Edward; Sejersted, Ole M & Carlson, Cathrine Rein (2016). Protein phosphatase 1c associated with the cardiac sodium calcium exchanger 1 regulates its activity by dephosphorylating Serine 68-phosphorylated phospholemman. Journal of Biological Chemistry.  ISSN 0021-9258.  291(9), s 4561- 4579 . doi: 10.1074/jbc.M115.677898 Vis sammendrag

  The sodium (Na+)-calcium (Ca2+) exchanger 1 (NCX1) is an important regulator of intracellular Ca2+ homeostasis. Serine 68 phosphorylated phospholemman (pSer-68-PLM) inhibits NCX1 activity. In the context of Na+/K+ ATPase (NKA) regulation, pSer-68-PLM is dephosphorylated by protein phosphatase 1 (PP1). PP1 also associates with NCX1, however, the molecular basis of this association is unknown. In the present study, we aimed to analyze the mechanisms of PP1 targeting to the NCX1-pSer-68-PLM complex and hypothesized that a direct and functional NCX1-PP1 interaction is a prerequisite for pSer-68-PLM dephosphorylation. Using a variety of molecular techniques, we show that PP1 catalytic subunit (PP1c) co-localized, co-fractionated, and co-immunoprecipitated with NCX1 in rat cardiomyocytes, left ventricle lysates and HEK293 cells. Bioinformatic analysis, immunoprecipitations, mutagenesis, pull-down experiments and peptide arrays constrained PP1c anchoring to the K-I/V-F-F motif in the first Ca2+ binding domain (CBD1) in NCX1. This binding site is also partially in agreement with the extended PP1 binding motif; K-I/V-F-F-X5-8-Φ1Φ2-X8-9-R. The cytosolic loop of NCX1, containing the K-I/V-F-F motif, had no effect on PP1 activity in an in vitro assay. Dephosphorylation of pSer-68-PLM in HEK293 cells was not observed when NCX1 was absent, when the K-I/V-F-F motif was mutated or when the PLM and PP1c binding sites were separated (mimicking calpain cleavage of NCX1). Co-expression of PLM and NCX1 inhibited NCX1 current (both modes). Moreover, co-expression of PLM with NCX1-(F407P) (mutated K-I/V-F-F motif) resulted in NCX1 current being completely abolished. In conclusion, NCX1 is a substrate-specifying PP1c regulator protein, indirectly regulating NCX1 activity through pSer-68-PLM dephosphorylation.

• Hortemo, Kristin Halvorsen; Lunde, Per Kristian; Anonsen, Jan Haug; Kvaløy, Heidi; Munkvik, Morten; Rehn, Tommy Aune; Sjaastad, Ivar; Lunde, Ida Gjervold; Aronsen, Jan Magnus & Sejersted, Ole M (2016). Exercise training increases protein O-GlcNAcylation in rat skeletal muscle. Physiological Reports.  ISSN 2051-817X.  4(18), s e12896 . doi: 10.14814/phy2.12896 Fulltekst i vitenarkiv.
• Logantha, Sunil Jit R.; Stokke, Mathis Korseberg; Atkinson, Andrew J.; Kharche, Sanjay R.; Parveen, Sajida; Saeed, Yawer; Sjaastad, Ivar; Sejersted, Ole M & Dobrzynski, Halina (2016). Ca2+ -clock-dependent pacemaking in the sinus node is impaired in mice with a cardiac specific reduction in SERCA2 abundance. Frontiers in Physiology.  ISSN 1664-042X.  7:197 . doi: 10.3389/fphys.2016.00197
• Manotheepan, Ravinea; Danielsen, Tore Kristian; Sadredini, Mani; Anderson, Mark E.; Carlson, Cathrine Rein; Lehnart, Stefan; Sjaastad, Ivar & Stokke, Mathis Korseberg (2016). Exercise training prevents ventricular tachycardia in CPVT1 due to reduced CaMKII-dependent arrhythmogenic Ca2+ release. Cardiovascular Research (CVR).  ISSN 0008-6363.  111(3), s 295- 306 . doi: 10.1093/cvr/cvw095
• Melleby, Arne Olav; Strand, Mari Elen; Romaine, Andreas; Herum, Kate Louise Møller; Skrbic, Biljana; Dahl, Christen Peder; Sjaastad, Ivar; Fiane, Arnt E; Filmus, Jorge; Christensen, Geir Arve & Lunde, Ida Gjervold (2016). The heparan sulfate proteoglycan glypican-6 is upregulated in the failing heart, and regulates cardiomyocyte growth through ERK1/2 Signaling. PLOS ONE.  ISSN 1932-6203.  11(10) . doi: 10.1371/journal.pone.0165079
• Sadredini, Mani; Danielsen, Tore Kristian; Aronsen, Jan Magnus; Manotheepan, Ravinea; Hougen, Karina; Sjaastad, Ivar & Stokke, Mathis Korseberg (2016). Beta-adrenoceptor stimulation reveals Ca2+ waves and sarcoplasmic reticulum Ca2+ depletion in left ventricular cardiomyocytes from post-infarction rats with and without heart failure. PLOS ONE.  ISSN 1932-6203.  11(4) . doi: 10.1371/journal.pone.0153887
• Schwartz, Thomas; Diederichsen, Louise Pyndt; Lundberg, Ingrid E.; Sjaastad, Ivar & Sanner, Helga (2016). Cardiac involvement in adult and juvenile idiopathic inflammatory myopathies. RMD Open.  ISSN 2056-5933.  2:e000291(2), s 1- 11 . doi: 10.1136/rmdopen-2016-000291
• Young-Halvorsen, Kristine Skårdal; Espe, Emil Knut Stenersen; Zhang, Lili; Aronsen, Jan Magnus & Sjaastad, Ivar (2016). Three-directional evaluation of mitral flow in the rat heart by phase-contrast cardiovascular magnetic resonance. PLOS ONE.  ISSN 1932-6203.  11(3) . doi: 10.1371/journal.pone.0150536 Fulltekst i vitenarkiv.
• Aronsen, Jan Magnus; Skogestad, Jonas; Lewalle, Alexandre; Louch, William Edward; Hougen, Karina; Stokke, Mathis Korseberg; Swift, Fredrik; Niederer, Steven; Smith, Nic P.; Sejersted, Ole M & Sjaastad, Ivar (2015). Hypokalaemia induces Ca2+ overload and Ca2+ waves in ventricular myocytes by reducing Na+ ,K+-ATPase α2 activity. Journal of Physiology.  ISSN 0022-3751.  593(6), s 1509- 1521 . doi: 10.1113/jphysiol.2014.279893
• Bolstad, Ingeborg; Andreassen, Ole Andreas; Groote, Inge Rasmus; SERVER, ANDRES; Sjaastad, Ivar; Kapur, S & Jensen, Jimmy Kristian (2015). Effects of haloperidol and aripiprazole on the human mesolimbic motivational system: A pharmacological fMRI study. European Neuropsychopharmacology.  ISSN 0924-977X.  25(12), s 2252- 2261 . doi: 10.1016/j.euroneuro.2015.09.016 Vis sammendrag

  The atypical antipsychotic drug aripiprazole is a partial dopamine (DA) D2 receptor agonist, which differentiates it from most other antipsychotics. This study compares the brain activation characteristic produced by aripiprazole with that of haloperidol, a typical D2 receptor antagonist. Healthy participants received an acute oral dose of haloperidol, aripiprazole or placebo, and then performed an active aversive conditioning task with aversive and neutral events presented as sounds, while blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) was carried out. The fMRI task, targeting the mesolimbic motivational system that is thought to be disturbed in psychosis, was based on the conditioned avoidance response (CAR) animal model – a widely used test of therapeutic potential of antipsychotic drugs. In line with the CAR animal model, the present results show that subjects given haloperidol were not able to avoid more aversive than neutral task trials, even though the response times were shorter during aversive events. In the aripiprazole and placebo groups more aversive than neutral events were avoided. Accordingly, the task-related BOLD-fMRI response in the mesolimbic motivational system was diminished in the haloperidol group compared to the placebo group, particularly in the ventral striatum, whereas the aripiprazole group showed task-related activations intermediate of the placebo and haloperidol groups. The current results show differential effects on brain function by aripiprazole and haloperidol, probably related to altered DA transmission. This supports the use of pharmacological fMRI to study antipsychotic properties in humans

• Dhondup, Yangchen; Sjaastad, Ivar; Scott, Helge; Sandanger, Øystein; Zhang, Lili; Haugstad, Solveig Bjærum; Aronsen, Jan Magnus; Ranheim, Trine; Holmen, Sigve; Alfsnes, Katrine; Ahmed, Muhammad Shakil; Attramadal, Håvard; Gullestad, Lars; Aukrust, Pål; Christensen, Geir Arve; Yndestad, Arne & Vinge, Leif Erik (2015). Sustained toll-like receptor 9 activation promotes systemic and cardiac inflammation, and aggravates diastolic heart failure in SERCA2a KO Mice. PLOS ONE.  ISSN 1932-6203.  10:e0139715(10) . doi: 10.1371/journal.pone.0139715 Fulltekst i vitenarkiv.
• Espe, Emil Knut Stenersen; Aronsen, Jan Magnus; Eriksen, Guro Søe; Zhang, Lili; Smiseth, Otto A.; Edvardsen, Thor; Sjaastad, Ivar & Eriksen, Morten (2015). Assessment of regional myocardial work in rats. Circulation Cardiovascular Imaging.  ISSN 1941-9651.  8 . doi: 10.1161/CIRCIMAGING.114.002695
• Fadila, Cero; Hillestad, Vigdis; Sjaastad, Ivar; Yndestad, Arne; Aukrust, Pål; Ranheim, Trine; Lunde, Ida Gjervold; Olsen, Maria Belland; Lien, Egil; Zhang, Lili; Haugstad, Solveig Bjærum; Løberg, Else Marit; Christensen, Geir Arve; Larsen, Karl-Otto & Skjønsberg, Ole Henning (2015). Absence of the inflammasome adaptor ASC reduces hypoxia-induced pulmonary hypertension in mice. American Journal of Physiology - Lung cellular and Molecular Physiology.  ISSN 1040-0605.  309(4), s L378- L387 . doi: 10.1152/ajplung.00342.2014
• Fadila, Cero; Hillestad, Vigdis; Sjaastad, Ivar; Yndestad, Arne; Aukrust, Pål; Ranheim, Trine; Lunde, Ida Gjervold; Olsen, Maria Belland; Lien, Egil; Zhang, Lili; Haugstad, Solveig Bjærum; Løberg, Else Marit; Christensen, Geir Arve; Larsen, Karl-Otto & Skjønsberg, Ole Henning (2015). Absence of the inflammasone adaptor ASC reduces hypoxia-induced pulmonary hypertension in mice. American Journal of Physiology - Lung cellular and Molecular Physiology.  ISSN 1040-0605.  309, s L378- L387 . doi: 10.1152/ajplung.00342.2014

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• Rønning, Sissel Beate; Carlson, Cathrine Rein; Aronsen, Jan Magnus; Høst, Vibeke; Pisconti, Addolorate; Lunde, Marianne; Liland, Kristian Hovde; Sjaastad, Ivar; Kolset, Svein Olav; Christensen, Geir Arve & Pedersen, Mona Elisabeth (2019). Extracellular Matrix remodeling and multiple signaling pathways are regulated by syndecan-4 during myogenesis.
• Rønning, Sissel Beate; Carlson, Cathrine Rein; Aronsen, Jan Magnus; Høst, Vibeke; Liland, Kristian Hovde; Stang, Espen; Sjaastad, Ivar; Kolset, Svein Olav; Christensen, Geir Arve & Pedersen, Mona Elisabeth (2017). Syndecan-4 is a skeletal muscle regenerator and is important for normal skeletal muscle fibre development..
• Albert, Ingrid; Skogestad, Jonas; Carlson, Cathrine Rein; Lunde, Marianne; Marshall, Serena; Lunde, Per Kristian; Sjaastad, Ivar & Aronsen, Jan Magnus (2016). Development of PDE3A-SERCA2 disruptor agents for SERCA2 activation..
• Aronsen, Jan Magnus; Skogestad, Jonas; Hougen, Karina; Lunde, Marianne; Lothe, Gustav B; Albert, Ingrid; Marshall, Serena; Børstad, Mira Halvorsen; Lunde, Per Kristian; Morth, Jens Preben; Tasken, Kjetil; Carlson, Cathrine Rein & Sjaastad, Ivar (2016). Physical coupling of PDE3A regulates SERCA2 activity in cardiomyocytes.
• Bendiksen, Bård Andre; Zhang, Lili; Espe, Emil Knut Stenersen; Schneider, Jurgen E. & Sjaastad, Ivar (2016). Cardiac diffusion tensor imaging of the rodent heart utilizing an optimized gradient configuration with multiple encoding strengths.
• Danielsen, Tore Kristian; Manotheepan, Ravinea; Sadredini, Mani; Leren, I.S.; Edwards, Andrew; Vincent, K.; Lehnart, Stefan; Sejersted, Ole M; Sjaastad, Ivar; Haugaa, Kristina & Stokke, Mathis Korseberg (2016). Mechanisms underlying the frequency-dependence of triggered arrhythmias in catecholaminergic polymorphic ventricular tachycardia type 1.
• Kolstad, Terje R Selnes; Macquaide, Niall; Hake, Johan; Aronsen, Jan Magnus; Frisk, Michael; Sjaastad, Ivar; Sejersted, Ole M & Louch, William Edward (2016). Dispersion of ryanodine receptor clusters disrupts calcium sparks in failing cardiomyocyte.
• Kolstad, Terje R Selnes; Macquaide, Niall; Hake, Johan; Aronsen, Jan Magnus; Frisk, Michael; Sjaastad, Ivar; Sejersted, Ole M & Louch, William Edward (2016). Super-resolution imaging reveals dispersion of ryanodine receptor clusters during heart failure.
• Krohn-Hansen, Dag; Zhang, Lili; Haaskjold, Erlend; Nicolaissen, Bjørn; Meling, Torstein Ragnar & Sjaastad, Ivar (2016). A less invasive surgical approach to the superior part of the orbit.
• Li, Jia; Frisk, Michael; Norseng, Per Andreas; Sjaastad, Ivar; Sejersted, Ole M & Louch, William Edward (2016). Regional activation of the Frank-Starling mechanism within the cardiomyocyte.
• Lipsett, David Bruce; Frisk, Michael; Aronsen, Jan Magnus; Sejersted, Ole M; Sjaastad, Ivar; Christensen, Geir Arve & Louch, William Edward (2016). Sarcolemmal structure and function revert to an immature phenotype in failing cardiomyocytes.
• Lipsett, David Bruce; Frisk, Michael; Aronsen, Jan Magnus; Singh, Neha; Sejersted, Ole M; Sjaastad, Ivar; Wasserstrom, J. Andrew; Christensen, Geir Arve & Louch, William Edward (2016). BIN1 triggers t-tubule development in cardiomyocytes.
• Manotheepan, Ravinea; Danielsen, Tore Kristian; Saberniak, Jorg; Sadredini, Mani; Anderson, Mark e.; Carlson, Cathrine Rein; Edvardsen, Thor; Lehnart, Stefan; Sjaastad, Ivar; Haugaa, Kristina & Stokke, Mathis Korseberg (2016). Exercise training as anti-arrhythmic therapy in cathecholaminergic polymorphic ventricular tachycardia type 1.
• Marshall, Serena; Børstad, Mira Halvorsen; Skogestad, Jonas; Albert, Ingrid; Lothe, Gustav B; Espe, Emil Knut Stenersen; Zhang, Lili; Louch, William Edward; Sjaastad, Ivar & Aronsen, Jan Magnus (2016). SERCA2 activation is beneficial in chronic heart disease.
• Marstein, Henriette; Lunde, Per Kristian; Aronsen, Jan Magnus & Sjaastad, Ivar (2016). Inhibition of Alkbh7 regulates cardiac metabolism.
• McGinley, Gary George; Bendiksen, Bård Andre; Zhang, Lili; Sjaastad, Ivar & Espe, Emil Knut Stenersen (2016). Accelerated myocardial velocity and strain estimation with phase-contrast magnetic resonance imaging using compressed sensing with adaptive thresholding.
• Melleby, Arne Olav; Strand, Mari Elen; Herum, Kate Louise Møller; Skrbic, Biljana; Dahl, Christen Peder; Sjaastad, Ivar; Fiane, Andrew; Filmus, Jorge; Christensen, Geir Arve & Lunde, Ida Gjervold (2016). Glypican-6 is upregulated in heart failure and mediates cardiomyocyte growth through ERK1/2 signaling.
• Mohammadzadeh, Naiyereh; Engebretsen, Kristin V Thunheim; Lunde, Ida Gjervold; Sjaastad, Ivar; Strand, Mari Elen; Marstein, Henriette; Aronsen, Jan Magnus; Nygård, Ståle; Skrbic, Biljana; Bandlien, Caroline; Andenæs, Kine; Chakravarti, Shukti; Christensen, Geir Arve & Tønnessen, Theis (2016). Lack of the extracellular matrix proteoglycan lumican leads to cardiac dysfunction in response to pressure overload.
• Mohammadzadeh, Naiyereh; Engebretsen, Kristin; Lunde, Ida Gjervold; Sjaastad, Ivar; Strand, Mari Elen; Marstein, Henriette; Aronsen, Jan Magnus; Nygård, Ståle; Skrbic, Biljana; Bandlien, Caroline; Andenæs, Kine; Chakravarti, Shukti; Christensen, Geir Arve & Tønnessen, Theis (2016). Lack of the extracellular matrix proteoglycan lumican leads to ventricular dilatation, attenuated hypertrophy and contractile dysfunction in response to pressure overload.
• Norden, Einar Sjaastad; Bergo, Kaja Knudsen; Zhang, Lili; Aronsen, Jan Magnus; Hasic, Almira; Hussain, I.; Sjaastad, Ivar & Cataliotti, Alessandro (2016). Anti-hypertrophic effects of LCZ696 in chronic cardiac pressure overload.
• Romaine, Andreas; Sørensen, Ida Wiig; Melleby, Arne Olav; Zeltz, Cedric; Zhang, Lili; Bendiksen, Bård Andre; Lu, Neha; Herum, Kate Louise Møller; Danielsen, D.; Sjaastad, Ivar; Gullberg, Donald & Christensen, Geir Arve (2016). Overexpression of integrin a11 induces cardiac hypertrophy and fibrosis.
• Ruud, Marianne; Frisk, Michael; Aronsen, Jan Magnus; Dahl, Christen Peder; Jølle, Guro Five; Aakhus, Svend; Lunde, Ida Gjervold; Almaas, Vibeke; Gullestad, Lars; Sjaastad, Ivar; Tønnessen, Theis; Sejersted, Ole M; Norseng, Per Andreas; Christensen, Geir Arve & Louch, William Edward (2016). Mechanical load regulates cardiomyocyte t-tubular structure and Ca2+ homeostasis.
• Ruud, Marianne; Frisk, Michael; Espe, Emil Knut Stenersen; Aronsen, Jan Magnus; Zhang, Lili; Norseng, Per Andreas; Sjaastad, Ivar; Sejersted, Ole M; Christensen, Geir Arve & Louch, William Edward (2016). Elevated ventricular wall stress disrupts cardiomyocyte t-tubular structure and Ca2+ homeostasis.
• Røe, Åsmund Treu; Ruud, Marianne; Espe, Emil Knut Stenersen; Aronsen, Jan Magnus; Sejersted, Ole M; Sjaastad, Ivar & Louch, William Edward (2016). Elevated ventricular wall stress disrupts diastolic Calcium homeostasis of the cardiomyocyte.
• Sadredini, Mani; Manotheepan, Ravinea; Danielsen, Tore Kristian; Lehnart, Stefan; Sjaastad, Ivar & Stokke, Mathis Korseberg (2016). Epac2 inhibition reduces arrhythmogenic Ca2+ wave frequently in cardiomyocytes from mice With catecholaminergic polymorphic ventricular tachcardia type 1.
• Skogestad, Jonas; Albert, Ingrid; Marshall, Serena; Børstad, Mira Halvorsen; Lothe, Gustav B; Sejersted, Ole M; Sjaastad, Ivar & Aronsen, Jan Magnus (2016). Phosphodiesterase 2 regulates Na+/K+-ATPase activity in adult cardiomyocytes.
• Skårdal, Kristine; Espe, Emil Knut Stenersen; Bendiksen, Bård Andre; Aronsen, Jan Magnus; Zhang, Lili & Sjaastad, Ivar (2016). Parametrizing active and passive diastolic function non-invasively using phase contrast MRI.
• Strand, Mari Elen; Aronsen, Jan Magnus; Skrbic, Biljana; Gelazaukaite, Monika; Sjaastad, Ivar; Christensen, Geir Arve & Lunde, Ida Gjervold (2016). The heparanase-syndecan-4 axis in the heart: upregulation in response to immune activation indicates a role in cardiac inflammation.
• Strand, Mari Elen; Aronsen, Jan Magnus; Skrbic, Biljana; Gelazauskaite, Monika; Sjaastad, Ivar; Christensen, Geir Arve & Lunde, Ida Gjervold (2016). The heparanase-syndecan-4 axis in the heart: upregulation in response to immune activation indicates a role in cardiac inflammation.
• Tazmini, Kiarash; Frisk, Michael; Lipsett, David Bruce; Aronsen, Jan Magnus; Sjaastad, Ivar; Øie, Erik & Louch, William Edward (2016). Pro-arrhythmic consequences of hypokalemia in atrial cardiomyocytes.
• Witzcak, Birgit; Schwartz, Thomas; Barth, Zoltan; Lund, M B; Sjaastad, Ivar & Sanner, Helga (2016). Cardiac dysfunction and pulmonary involvement are not associated in juvenile dermatomyositis.
• Albert, Ingrid; Børstad, Mira Halvorsen; Carlson, Cathrine Rein; Calejo, Anna; Skogestad, Jonas; Lunde, Marianne; Lunde, Per Kristian; Tasken, Kjetil; Sjaastad, Ivar & Aronsen, Jan Magnus (2015). Development of SERCA2 activating agents.
• Andenæs, Kine; Mohammadzadeh, Naiyereh; Lunde, Ida Gjervold; Strand, Mari Elen; Marstein, Henriette; Dahl, Christen Peder; Sjaastad, Ivar; Christensen, Geir Arve; Engebretsen, Kristin V Thunheim & Tønnessen, Theis (2015). The extracellular matrix proteoglycan fibromodulin is up-regulated in experimental and clinical heart failure, and might be involved in regulation of myocardial fibrosis by interacting with TGF-B.
• Aronsen, Jan Magnus; Skogestad, Jonas; Hougen, Karina; Lunde, Marianne; Lothe, Gustav B; Albert, Ingrid; Marshall, Serena; Lunde, Per Kristian; Morth, Jens Preben; Tasken, Kjetil; Carlson, Cathrine Rein & Sjaastad, Ivar (2015). Physical coupling between SERCA2 and PDE3A regulates SERCA2 activity in cardiomyocytes.
• Barth, Zoltan; Witzcak, Birgit; Schwartz, Thomas; Gjesdal, Knut; Flatø, Berit; Koller, A'kos; Sanner, Helga & Sjaastad, Ivar (2015). Heart rate variability is related to inflammation and cardiac function in juvenile dermatomyositis.
• Barth, Zoltan; Witzcak, Birgit; Schwartz, Thomas; Gjesdal, Knut; Flatø, Berit; Koller, A'kos; Sjaastad, Ivar & Sanner, Helga (2015). Heart rate variability is related to inflammation and cardiac function in juvenile dermatomyositis.
• Børstad, Mira Halvorsen; Albert, Ingrid; Lunde, Marianne; Carlson, Cathrine Rein; Sjaastad, Ivar & Aronsen, Jan Magnus (2015). Molecular mechanisms for PDE3A mediated inhibition of SERCA2 activity.
• Cero, Fadila; Larsen, Karl-Otto; Hillestad, Vigdis; Olsen, Maria Belland; Udjus, Camilla; Sjaastad, Ivar; Yndestad, Arne; Aukrust, Pål; Løberg, Else Marit; Christensen, Geir Arve & Skjønsberg, Ole Henning (2015). The inflammasome adaptor ASC mediates pulmonary artery remodelling.
• Danielsen, Tore Kristian; Manotheepan, Ravinea; Sadredini, Mani Nikoo; Gaur, Namit; Leren, IS; Edwards, Andrew; Sejersted, Ole M; Lehnart, Stefan; Sjaastad, Ivar; Haugaa, Kristina & Stokke, Mathis Korseberg (2015). Mechanisms for the frequency-dependence of triggered activity in catecholaminergic polymorphic ventricular tachycardia type 1.
• Espe, Emil Knut Stenersen; Aronsen, Jan Magnus; Skårdal, Kristine; Zhang, Lili & Sjaastad, Ivar (2015). Noninvasive detection of congestive heart failure in postinfarction rats.
• Frisk, Michael; Aronsen, Jan Magnus; Dahl, Christen Peder; Lunde, Ida Gjervold; Jølle, Guro Five; Almaas, Victor; Gullestad, Lars; Christensen, Geir Arve; Aakhus, Svend; Sejersted, Ole M; Tønnessen, Theis; Sjaastad, Ivar & Louch, William Edward (2015). Maintained cardiomyocyte t-tubule structure and function in patients with non-dilated hypertrophy.
• Frisk, Michael; Ruud, Marianne; Espe, Emil Knut Stenersen; Aronsen, Jan Magnus; Røe, Åsmund Treu; Zhang, Lili; Norseng, Per Andreas; Christensen, Geir Arve; Sejersted, Ole M; Sjaastad, Ivar & Louch, William Edward (2015). Ventricular wall stress predicts disruption of cardiomyocyte t-tubule structure and Ca2+ homeostasis across the infarcted heart. Biophysical Journal.  ISSN 0006-3495.  108, s 106a

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