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Editorial
. 2021 Sep 28;117(11):2291-2293.
doi: 10.1093/cvr/cvab124.

Oxidative stress: a bystander or a causal contributor to atrial remodelling and fibrillation?

Affiliations
Editorial

Oxidative stress: a bystander or a causal contributor to atrial remodelling and fibrillation?

Dobromir Dobrev et al. Cardiovasc Res. .
No abstract available

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Figures

Figure 1
Figure 1
Putative role of reactive oxygen species (ROS) in atrial fibrillation (AF). ROS-production from activated NADPH-oxidase (NOX) isoforms, xanthine oxidase, and downstream ROS-generating systems including mitochondria and uncoupled eNOS. The sustained oxidative stress leads to abnormal Ca2+ signalling with potential occurrence of AF-triggering EADs and DADs, ion-channel dysfunction with ERP/APD-abbreviation, and to altered gap-junctions, fibrosis, myocyte apoptosis, and inflammation, which produce a heterogeneous slowing in impulse conduction. Shorter ERP and conduction slowing support the formation of AF-maintaining reentry. Examples of key mediators downstream of increased ROS-production include oxidized CaMKII (CaMKII), activated PKC, inhibited PP1, and activated NFkB and NLRP3-inflammasome. Activated CaMKII increases ryanodine-receptor type-2 (RyR2) hyperphospohrylation and causes sarcoplasmic reticulum Ca2+-overload, both of which increases diastolic Ca2+-leak. NFkB is a redox-sensitive transcription factor that activates NLRP3-inflammatory signalling and causes structural remodelling by increasing the priming of NLRP3, interleukin-1β (IL-1β), and matrix metalloproteinases. ROS-generation also increases lipid peroxidation and formation of highly reactive isolevuglandins that rapidly adduct and crosslink proteins causing myocyte proteotoxicity. AF further increases the activity of ROS-generating systems by increasing both angiotensin-II (Ang-II) and atrial stretch, creating a vicious cycle of atrial cardiomyopathy-driven NOX-activation and AF-mediated oxidative stress amplification, ultimately leading to AF-promoting atrial remodelling. APD, action-potential duration; CaMKII, Ca2+-calmodulin-dependent protein kinase-II; Cx43, connexin-43; DAD, delayed afterdepolarization; EAD, early afterdepolarization; eNOS, endothelial nitric oxide; ERP, effective refractory period; INa, Na+-current; ISK, small-conductance Ca2+-activated K+-current; Ito, transient-outward K+-current; JNK2, janus kinase-2; NFkB, nuclear-factor kappa-B; NLRP3, NLR family pyrin-domains containing protein-3; PKC, protein kinase-C; PP1, protein phosphatase type-1; UPR, unfolded protein response.

Comment on

References

    1. Nattel S, Heijman J, Zhou L, Dobrev D.. Molecular basis of atrial fibrillation pathophysiology and therapy: a translational perspective. Circ Res 2020;127:51–72. - PMC - PubMed
    1. Reilly SN, Jayaram R, Nahar K, Antoniades C, Verheule S, Channon KM, Alp NJ, Schotten U, Casadei B.. Atrial sources of reactive oxygen species vary with the duration and substrate of atrial fibrillation: implications for the antiarrhythmic effect of statins. Circulation 2011;124:1107–1117. - PubMed
    1. Neuman RB, Bloom HL, Shukrullah I, Darrow LA, Kleinbaum D, Jones DP, Dudley SC Jr.. Oxidative stress markers are associated with persistent atrial fibrillation. Clin Chem 2007;53:1652–1657. - PMC - PubMed
    1. Mighiu AS, Recalde A, Ziberna K, Carnicer R, Tomek J, Bub G, Brewer AC, Verheule S, Shah AM, Simon JN, Casadei B.. Inducibility, but not stability, of atrial fibrillation is increased by NOX2 overexpression in mice. Cardiovasc Res 2021;117:2354–2364. - PMC - PubMed
    1. Zheng Z, Jayaram R, Jiang L, Emberson J, Zhao Y, Li Q, Du J, Guarguagli S, Hill M, Chen Z, Collins R, Casadei B.. Perioperative rosuvastatin in cardiac surgery. N Engl J Med 2016;374:1744–1753. - PubMed