Abstract
Cardiovascular disease (CVD) is a major public health problem, particularly in the industrialised world, with diverse causes. Central to these underlying aetiologies is a progressive loss of functional cardiomyocytes, maladaptive remodelling, and resultant cardiac dysfunction. The ageing heart is characterised by perturbations in numerous signalling pathways, impairing its ability to repair and replace injured cardiomyocytes. This is caused at least in part by dysregulation of redox signalling- both in regard to production of reactive oxygen species (ROS), and disruption of cellular protective mechanisms. Cardiac regeneration is one area of particular therapeutic promise, which seeks to ameliorate cardiac function by either (1) direct application of stem cells, (2) modification of molecular signalling pathways to restore the endogenous reparative capacity of the heart, or (3) a combination of these two approaches. Unravelling these molecular and cellular signalling pathways is paramount to unlocking the potential of cardiac regenerative therapies, and theoretically revolutionising the medical management of patients with heart failure.
In this chapter, we will review the role of oxidative stress in cardiovascular disease, and the pathophysiological molecular signalling pathways that are involved in the transition from young to ageing heart. We will then provide an overview of the molecular therapies that are used to target these pathways to enhance heart regeneration, future directions involving cellular and novel ‘bio-printing’ based approaches, in addition to current promising clinical trials.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Aonuma T, Takehara N, Maruyama K, Kabara M, Matsuki M, Yamauchi A, Kawabe J, Hasebe N (2016) Apoptosis-resistant cardiac progenitor cells modified with apurinic/apyrimidinic endonuclease/redox factor 1 gene overexpression regulate cardiac repair after myocardial infarction. Stem Cells Transl Med 5:1067–1078
Arabacilar P, Marber M (2015) The case for inhibiting p38 mitogen-activated protein kinase in heart failure. Front Pharmacol 6:102
Bergmann O, Bhardwaj RD, Bernard S, Zdunek S, Barnabe-Heider F, Walsh S, Zupicich J, Alkass K, Buchholz BA, Druid H, Jovinge S, Frisen J (2009) Evidence for cardiomyocyte renewal in humans. Science 324:98–102
Bolli R, Chugh AR, D’Amario D, Loughran JH, Stoddard MF, Ikram S, Beache GM, Wagner SG, Leri A, Hosoda T, Sanada F, Elmore JB, Goichberg P, Cappetta D, Solankhi NK, Fahsah I, Rokosh DG, Slaughter MS, Kajstura J, Anversa P (2011) Cardiac stem cells in patients with ischaemic cardiomyopathy (SCIPIO): initial results of a randomised phase 1 trial. Lancet 378:1847–1857
Briceno N, Schuster A, Lumley M, Perera D (2016) Ischaemic cardiomyopathy: pathophysiology, assessment and the role of revascularisation. Heart 102:397–406
Brugts JJ, van Vark L, Akkerhuis M, Bertrand M, Fox K, Mourad JJ, Boersma E (2015) Impact of renin-angiotensin system inhibitors on mortality and major cardiovascular endpoints in hypertension: a number-needed-to-treat analysis. Int J Cardiol 181:425–429
Bubb KJ, Birgisdottir AB, Tang O, Hansen T, Figtree GA (2017) Redox modification of caveolar proteins in the cardiovascular system- role in cellular signalling and disease. Free Radic Biol Med 109:61–74
Cabrera-Fuentes HA, Aragones J, Bernhagen J, Boening A, Boisvert WA, Botker HE, Bulluck H, Cook S, Di Lisa F, Engel FB, Engelmann B, Ferrazzi F, Ferdinandy P, Fong A, Fleming I, Gnaiger E, Hernandez-Resendiz S, Kalkhoran SB, Kim MH, Lecour S, Liehn EA, Marber MS, Mayr M, Miura T, Ong SB, Peter K, Sedding D, Singh MK, Suleiman MS, Schnittler HJ, Schulz R, Shim W, Tello D, Vogel CW, Walker M, Li QO, Yellon DM, Hausenloy DJ, Preissner KT (2016) From basic mechanisms to clinical applications in heart protection, new players in cardiovascular diseases and cardiac theranostics: meeting report from the third international symposium on “New frontiers in cardiovascular research”. Basic Res Cardiol 111:69
Cambria E, Pasqualini FS, Wolint P, Gunter J, Steiger J, Bopp A, Hoerstrup SP, Emmert MY (2017) Translational cardiac stem cell therapy: advancing from first-generation to next-generation cell types. NPJ Regen Med 2:17
Cannata A, Camparini L, Sinagra G, Giacca M, Loffredo FS (2016) Pathways for salvage and protection of the heart under stress: novel routes for cardiac rejuvenation. Cardiovasc Res 111:142–153
Cesselli D, Aleksova A, Sponga S, Cervellin C, Di Loreto C, Tell G, Beltrami AP (2017) Cardiac cell senescence and redox signaling. Front Cardiovasc Med 4:38
Chen CA, Wang TY, Varadharaj S, Reyes LA, Hemann C, Talukder MA, Chen YR, Druhan LJ, Zweier JL (2010) S-glutathionylation uncouples eNOS and regulates its cellular and vascular function. Nature 468:1115–1118
Chen J, Song W, Amato K (2015) Eph receptor tyrosine kinases in cancer stem cells. Cytokine Growth Factor Rev 26:1–6
Cheng G, Wei L, Xiurong W, Xiangzhen L, Shiguang Z, Songbin F (2009) IL-17 stimulates migration of carotid artery vascular smooth muscle cells in an MMP-9 dependent manner via p38 MAPK and ERK1/2-dependent NF-kappaB and AP-1 activation. Cell Mol Neurobiol 29:1161–1168
Collins LR, Priest C, Caras I, Littman N, Kadyk L (2015) Proceedings: moving toward cell-based therapies for heart disease. Stem Cells Transl Med 4:863–867
Contreras A, Orozco AF, Resende M, Schutt RC, Traverse JH, Henry TD, Lai D, Cooke JP, Bolli R, Cohen ML, Moye L, Pepine CJ, Yang PC, Perin EC, Willerson JT, Taylor DA, Cardiovascular Cell Therapy Research N (2017) Identification of cardiovascular risk factors associated with bone marrow cell subsets in patients with STEMI: a biorepository evaluation from the CCTRN TIME and LateTIME clinical trials. Basic Res Cardiol 112:3
Csiszar A, Labinskyy N, Perez V, Recchia FA, Podlutsky A, Mukhopadhyay P, Losonczy G, Pacher P, Austad SN, Bartke A, Ungvari Z (2008) Endothelial function and vascular oxidative stress in long-lived GH/IGF-deficient Ames dwarf mice. Am J Physiol Heart Circ Physiol 295:H1882–H1894
Di Baldassarre A, Cimetta E, Bollini S, Gaggi G, Ghinassi B (2018) Human-induced pluripotent stem cell technology and cardiomyocyte generation: progress and clinical applications. Cells 7
Dumitrascu R, Kulcke C, Konigshoff M, Kouri F, Yang X, Morrell N, Ghofrani HA, Weissmann N, Reiter R, Seeger W, Grimminger F, Eickelberg O, Schermuly RT, Pullamsetti SS (2011) Terguride ameliorates monocrotaline-induced pulmonary hypertension in rats. Eur Respir J 37:1104–1118
Ellison GM, Torella D, Dellegrottaglie S, Perez-Martinez C, Perez de Prado A, Vicinanza C, Purushothaman S, Galuppo V, Iaconetti C, Waring CD, Smith A, Torella M, Cuellas Ramon C, Gonzalo-Orden JM, Agosti V, Indolfi C, Galinanes M, Fernandez-Vazquez F, Nadal-Ginard B (2011) Endogenous cardiac stem cell activation by insulin-like growth factor-1/hepatocyte growth factor intracoronary injection fosters survival and regeneration of the infarcted pig heart. J Am Coll Cardiol 58:977–986
Engel FB, Hsieh PC, Lee RT, Keating MT (2006) FGF1/p38 MAP kinase inhibitor therapy induces cardiomyocyte mitosis, reduces scarring, and rescues function after myocardial infarction. Proc Natl Acad Sci U S A 103:15546–15551
Gentile C (2016) Filling the gaps between the in vivo and in vitro microenvironment: engineering of spheroids for stem cell technology. Curr Stem Cell Res Ther 11:652–665
Goichberg P, Kannappan R, Cimini M, Bai Y, Sanada F, Sorrentino A, Signore S, Kajstura J, Rota M, Anversa P, Leri A (2013) Age-associated defects in EphA2 signaling impair the migration of human cardiac progenitor cells. Circulation 128:2211–2223
Goichberg P, Chang J, Liao R, Leri A (2014) Cardiac stem cells: biology and clinical applications. Antioxid Redox Signal 21:2002–2017
Guo J, Jie W, Shen Z, Li M, Lan Y, Kong Y, Guo S, Li T, Zheng S (2014) SCF increases cardiac stem cell migration through PI3K/AKT and MMP2/9 signaling. Int J Mol Med 34:112–118
Hafstad AD, Nabeebaccus AA, Shah AM (2013) Novel aspects of ROS signalling in heart failure. Basic Res Cardiol 108:359
Hao J, Du H, Li W, Liu F, Lu J, Yang X, Cui W (2016) Anthocyanins protected hearts against ischemic injury by reducing MMP-2 activity via Akt/P38 pathways. Am J Transl Res 8:1100–1107
Herrero D, Tome M, Canon S, Cruz FM, Carmona RM, Fuster E, Roche E, Bernad A (2018) Redox-dependent BMI1 activity drives in vivo adult cardiac progenitor cell differentiation. Cell Death Differ 25:807–820
Heusch G (2015) Mitochondria at the heart of cardiovascular protection: p66shc-friend or foe? Eur Heart J 36:469–471
Hong KU, Guo Y, Li QH, Cao P, Al-Maqtari T, Vajravelu BN, Du J, Book MJ, Zhu X, Nong Y, Bhatnagar A, Bolli R (2014) c-kit+ Cardiac stem cells alleviate post-myocardial infarction left ventricular dysfunction despite poor engraftment and negligible retention in the recipient heart. PLoS One 9:e96725
Hou J, Wang L, Long H, Wu H, Wu Q, Zhong T, Chen X, Zhou C, Guo T, Wang T (2017) Hypoxia preconditioning promotes cardiac stem cell survival and cardiogenic differentiation in vitro involving activation of the HIF-1alpha/apelin/APJ axis. Stem Cell Res Ther 8:215
Ito K, Suda T (2014) Metabolic requirements for the maintenance of self-renewing stem cells. Nat Rev Mol Cell Biol 15:243–256
Jung SN, Yang WK, Kim J, Kim HS, Kim EJ, Yun H, Park H, Kim SS, Choe W, Kang I, Ha J (2008) Reactive oxygen species stabilize hypoxia-inducible factor-1 alpha protein and stimulate transcriptional activity via AMP-activated protein kinase in DU145 human prostate cancer cells. Carcinogenesis 29:713–721
Katz JN, Waters SB, Hollis IB, Chang PP (2015) Advanced therapies for end-stage heart failure. Curr Cardiol Rev 11:63–72
Kelley MR, Georgiadis MM, Fishel ML (2012) APE1/Ref-1 role in redox signaling: translational applications of targeting the redox function of the DNA repair/redox protein APE1/Ref-1. Curr Mol Pharmacol 5:36–53
Kittleson MM (2018) Recent advances in heart transplantation. F1000Res:7
Kocabas F, Mahmoud AI, Sosic D, Porrello ER, Chen R, Garcia JA, DeBerardinis RJ, Sadek HA (2012) The hypoxic epicardial and subepicardial microenvironment. J Cardiovasc Transl Res 5:654–665
Kohler AC, Sag CM, Maier LS (2014) Reactive oxygen species and excitation-contraction coupling in the context of cardiac pathology. J Mol Cell Cardiol 73:92–102
Larson MG (1995) Assessment of cardiovascular risk factors in the elderly: the Framingham Heart Study. Stat Med 14:1745–1756
Leong YY, Ng WH, Ellison-Hughes GM, Tan JJ (2017) Cardiac stem cells for myocardial regeneration: they are not alone. Front Cardiovasc Med 4:47
Lin Z, Pu WT (2014) Strategies for cardiac regeneration and repair. Sci Transl Med 6:239rv231
Lundy SD, Gantz JA, Pagan CM, Filice D, Laflamme MA (2014) Pluripotent stem cell derived cardiomyocytes for cardiac repair. Curr Treat Options Cardiovasc Med 16:319
Luo YX, Tang X, An XZ, Xie XM, Chen XF, Zhao X, Hao DL, Chen HZ, Liu DP (2017) SIRT4 accelerates Ang II-induced pathological cardiac hypertrophy by inhibiting manganese superoxide dismutase activity. Eur Heart J 38:1389–1398
Mandal CC, Ganapathy S, Gorin Y, Mahadev K, Block K, Abboud HE, Harris SE, Ghosh-Choudhury G, Ghosh-Choudhury N (2011) Reactive oxygen species derived from Nox4 mediate BMP2 gene transcription and osteoblast differentiation. Biochem J 433:393–402
Mao AS, Mooney DJ (2015) Regenerative medicine: current therapies and future directions. Proc Natl Acad Sci U S A 112:14452–14459
Martin CM, Ferdous A, Gallardo T, Humphries C, Sadek H, Caprioli A, Garcia JA, Szweda LI, Garry MG, Garry DJ (2008) Hypoxia-inducible factor-2alpha transactivates Abcg2 and promotes cytoprotection in cardiac side population cells. Circ Res 102:1075–1081
Masumoto H, Ikuno T, Takeda M, Fukushima H, Marui A, Katayama S, Shimizu T, Ikeda T, Okano T, Sakata R, Yamashita JK (2014) Human iPS cell-engineered cardiac tissue sheets with cardiomyocytes and vascular cells for cardiac regeneration. Sci Rep 4:6716
Matasic DS, Brenner C, London B (2018) Emerging potential benefits of modulating NAD(+) metabolism in cardiovascular disease. Am J Physiol Heart Circ Physiol 314:H839–H852
Mathiasen AB, Qayyum AA, Jorgensen E, Helqvist S, Fischer-Nielsen A, Kofoed KF, Haack-Sorensen M, Ekblond A, Kastrup J (2015) Bone marrow-derived mesenchymal stromal cell treatment in patients with severe ischaemic heart failure: a randomized placebo-controlled trial (MSC-HF trial). Eur Heart J 36:1744–1753
Mawad D, Figtree G, Gentile C (2017) Current technologies based on the knowledge of the stem cells microenvironments. Adv Exp Med Biol 1041:245–262
Menasche P, Hagege AA, Scorsin M, Pouzet B, Desnos M, Duboc D, Schwartz K, Vilquin JT, Marolleau JP (2001) Myoblast transplantation for heart failure. Lancet 357:279–280
Menasche P, Alfieri O, Janssens S, McKenna W, Reichenspurner H, Trinquart L, Vilquin JT, Marolleau JP, Seymour B, Larghero J, Lake S, Chatellier G, Solomon S, Desnos M, Hagege AA (2008) The myoblast autologous grafting in ischemic cardiomyopathy (MAGIC) trial: first randomized placebo-controlled study of myoblast transplantation. Circulation 117:1189–1200
Menasche P, Vanneaux V, Hagege A, Bel A, Cholley B, Parouchev A, Cacciapuoti I, Al-Daccak R, Benhamouda N, Blons H, Agbulut O, Tosca L, Trouvin JH, Fabreguettes JR, Bellamy V, Charron D, Tartour E, Tachdjian G, Desnos M, Larghero J (2018) Transplantation of Human Embryonic Stem Cell-Derived Cardiovascular Progenitors for Severe Ischemic Left Ventricular Dysfunction. J Am Coll Cardiol 71:429–438
Munzel T, Gori T, Keaney JF Jr, Maack C, Daiber A (2015) Pathophysiological role of oxidative stress in systolic and diastolic heart failure and its therapeutic implications. Eur Heart J 36:2555–2564
Nobrega-Pereira S, Fernandez-Marcos PJ, Brioche T, Gomez-Cabrera MC, Salvador-Pascual A, Flores JM, Vina J, Serrano M (2016) G6PD protects from oxidative damage and improves healthspan in mice. Nat Commun 7:10894
Orlic D, Kajstura J, Chimenti S, Jakoniuk I, Anderson SM, Li B, Pickel J, McKay R, Nadal-Ginard B, Bodine DM, Leri A, Anversa P (2001) Bone marrow cells regenerate infarcted myocardium. Nature 410:701–705
Pastore A, Piemonte F (2013) Protein glutathionylation in cardiovascular diseases. Int J Mol Sci 14:20845–20876
Planavila A, Iglesias R, Giralt M, Villarroya F (2011) Sirt1 acts in association with PPARalpha to protect the heart from hypertrophy, metabolic dysregulation, and inflammation. Cardiovasc Res 90:276–284
Polonchuk L, Chabria M, Badi L, Hoflack JC, Figtree G, Davies MJ, Gentile C (2017) Cardiac spheroids as promising in vitro models to study the human heart microenvironment. Sci Rep 7:7005
Puente BN, Kimura W, Muralidhar SA, Moon J, Amatruda JF, Phelps KL, Grinsfelder D, Rothermel BA, Chen R, Garcia JA, Santos CX, Thet S, Mori E, Kinter MT, Rindler PM, Zacchigna S, Mukherjee S, Chen DJ, Mahmoud AI, Giacca M, Rabinovitch PS, Aroumougame A, Shah AM, Szweda LI, Sadek HA (2014) The oxygen-rich postnatal environment induces cardiomyocyte cell-cycle arrest through DNA damage response. Cell 157:565–579
Qin F, Siwik DA, Pimentel DR, Morgan RJ, Biolo A, Tu VH, Kang YJ, Cohen RA, Colucci WS (2014) Cytosolic H2O2 mediates hypertrophy, apoptosis, and decreased SERCA activity in mice with chronic hemodynamic overload. Am J Physiol Heart Circ Physiol 306:H1453–H1463
Redfield MM, Jacobsen SJ, Borlaug BA, Rodeheffer RJ, Kass DA (2005) Age- and gender-related ventricular-vascular stiffening: a community-based study. Circulation 112:2254–2262
Reinecke H, MacDonald GH, Hauschka SD, Murry CE (2000) Electromechanical coupling between skeletal and cardiac muscle. Implications for infarct repair. J Cell Biol 149:731–740
Sanada F, Kim J, Czarna A, Chan NY, Signore S, Ogorek B, Isobe K, Wybieralska E, Borghetti G, Pesapane A, Sorrentino A, Mangano E, Cappetta D, Mangiaracina C, Ricciardi M, Cimini M, Ifedigbo E, Perrella MA, Goichberg P, Choi AM, Kajstura J, Hosoda T, Rota M, Anversa P, Leri A (2014) c-Kit-positive cardiac stem cells nested in hypoxic niches are activated by stem cell factor reversing the aging myopathy. Circ Res 114:41–55
Sattler S, Fairchild P, Watt FM, Rosenthal N, Harding SE (2017) The adaptive immune response to cardiac injury-the true roadblock to effective regenerative therapies? NPJ Regen Med 2:19
Senyo SE, Steinhauser ML, Pizzimenti CL, Yang VK, Cai L, Wang M, Wu TD, Guerquin-Kern JL, Lechene CP, Lee RT (2013) Mammalian heart renewal by pre-existing cardiomyocytes. Nature 493:433–436
Stubbs SL, Crook JM, Morrison WA, Newcomb AE (2011) Toward clinical application of stem cells for cardiac regeneration. Heart Lung Circ 20:173–179
Tang YL, Zhu W, Cheng M, Chen L, Zhang J, Sun T, Kishore R, Phillips MI, Losordo DW, Qin G (2009) Hypoxic preconditioning enhances the benefit of cardiac progenitor cell therapy for treatment of myocardial infarction by inducing CXCR4 expression. Circ Res 104:1209–1216
The Lancet E (2014) Expression of concern: the SCIPIO trial. Lancet 383:1279
Tran C, Damaser MS (2015) Stem cells as drug delivery methods: application of stem cell secretome for regeneration. Adv Drug Deliv Rev 82–83:1–11
U.S. National Library of Medicine (2012) Compare the effects of single versus repeated intracoronary application of autologous bone marrow-derived mononuclear cells on mortality in patients with chronic post-infarction heart failure (REPEAT). Interventional (Clinical Trial)
U.S. National Library of Medicine (2018a) CardiAMP CMI randomized controlled pivotal trial in patients with chronic myocardial ischemia and refractory angina (CardiAMP CMI). Interventional 2018
U.S. National Library of Medicine (2018b) Combination of mesenchymal and C-kit+ cardiac stem cells as regenerative therapy for heart failure (CONCERT-HF). Interventional
U.S. National Library of Medicine (2018c) Efficacy and safety of allogeneic mesenchymal precursor cells (rexlemestrocel-L) for the treatment of heart failure. (DREAM HF-1). Interventional
U.S. National Library of Medicine (2018d) A study of VentriGel in post-MI patients
Valiente-Alandi I, Albo-Castellanos C, Herrero D, Arza E, Garcia-Gomez M, Segovia JC, Capecchi M, Bernad A (2015) Cardiac Bmi1(+) cells contribute to myocardial renewal in the murine adult heart. Stem Cell Res Ther 6:205
Vasan RS, Sullivan LM, D’Agostino RB, Roubenoff R, Harris T, Sawyer DB, Levy D, Wilson PW (2003) Serum insulin-like growth factor I and risk for heart failure in elderly individuals without a previous myocardial infarction: the Framingham Heart Study. Ann Intern Med 139:642–648
Vicinanza C, Aquila I, Scalise M, Cristiano F, Marino F, Cianflone E, Mancuso T, Marotta P, Sacco W, Lewis FC, Couch L, Shone V, Gritti G, Torella A, Smith AJ, Terracciano CM, Britti D, Veltri P, Indolfi C, Nadal-Ginard B, Ellison-Hughes GM, Torella D (2017) Adult cardiac stem cells are multipotent and robustly myogenic: c-kit expression is necessary but not sufficient for their identification. Cell Death Differ 24:2101–2116
Wang K, Ding R, Ha Y, Jia Y, Liao X, Wang S, Li R, Shen Z, Xiong H, Guo J, Jie W (2018a) Hypoxia-stressed cardiomyocytes promote early cardiac differentiation of cardiac stem cells through HIF-1alpha/Jagged1/Notch1 signaling. Acta Pharm Sin B 8:795–804
Wang YL, Zhang G, Wang HJ, Tan YZ, Wang XY (2018b) Preinduction with bone morphogenetic protein-2 enhances cardiomyogenic differentiation of c-kit(+) mesenchymal stem cells and repair of infarcted myocardium. Int J Cardiol 265:173–180
Yamanaka S, Li J, Kania G, Elliott S, Wersto RP, Van Eyk J, Wobus AM, Boheler KR (2008) Pluripotency of embryonic stem cells. Cell Tissue Res 331:5–22
Yan B, Singla DK (2013) Transplanted induced pluripotent stem cells mitigate oxidative stress and improve cardiac function through the Akt cell survival pathway in diabetic cardiomyopathy. Mol Pharm 10:3425–3432
Ye L, Chang YH, Xiong Q, Zhang P, Zhang L, Somasundaram P, Lepley M, Swingen C, Su L, Wendel JS, Guo J, Jang A, Rosenbush D, Greder L, Dutton JR, Zhang J, Kamp TJ, Kaufman DS, Ge Y, Zhang J (2014) Cardiac repair in a porcine model of acute myocardial infarction with human induced pluripotent stem cell-derived cardiovascular cells. Cell Stem Cell 15:750–761
Yokota T, Wang Y (2016) p38 MAP kinases in the heart. Gene 575:369–376
Yoon HE, Kim EN, Kim MY, Lim JH, Jang IA, Ban TH, Shin SJ, Park CW, Chang YS, Choi BS (2016) Age-associated changes in the vascular renin-angiotensin system in mice. Oxid Med Cell Longev 2016:6731093
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2019 Springer Nature Singapore Pte Ltd.
About this chapter
Cite this chapter
Hansen, T., Saleh, S., Figtree, G.A., Gentile, C. (2019). The Role of Redox Signalling in Cardiovascular Regeneration. In: Chakraborti, S., Dhalla, N., Ganguly, N., Dikshit, M. (eds) Oxidative Stress in Heart Diseases. Springer, Singapore. https://doi.org/10.1007/978-981-13-8273-4_2
Download citation
DOI: https://doi.org/10.1007/978-981-13-8273-4_2
Published:
Publisher Name: Springer, Singapore
Print ISBN: 978-981-13-8272-7
Online ISBN: 978-981-13-8273-4
eBook Packages: Biomedical and Life SciencesBiomedical and Life Sciences (R0)