The effects of polyunsaturated fatty acids and antioxidant vitamins on atrial oxidative stress, nitrotyrosine residues, and connexins following extracorporeal circulation in patients undergoing cardiac surgery
Author
dc.contributor.author
Petersen, Felipe
Author
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Rodrigo Salinas, Ramón
Author
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Richter, Manfred
Author
dc.contributor.author
Kostin, Sawa
Admission date
dc.date.accessioned
2018-07-09T14:01:33Z
Available date
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2018-07-09T14:01:33Z
Publication date
dc.date.issued
2017
Cita de ítem
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Mol Cell Biochem (2017) 433:27–40
es_ES
Identifier
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10.1007/s11010-017-3013-1
Identifier
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https://repositorio.uchile.cl/handle/2250/149620
Abstract
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Cardiac surgery with extracorporeal circulation is characterized by different degrees of myocardial ischemia/reperfusion, which is often associated with postoperative atrial fibrillation (POAF). We have previously shown that a novel preventive therapy based on the reinforcement of the antioxidant system using omega-3 fatty acids plus antioxidant vitamin supplementation applied to patients undergoing cardiac surgery reduces POAF occurrence. We hypothesized that oxidative stress and nitrosative stress are involved in the development of an arrhythmogenic substrate by their effect on connexins (Cx40, Cx43 and Cx45) abundance and distribution pattern. Therefore, we have assessed the effect of redox status on atrial tissue in patients undergoing cardiac surgery. Placebo/POAF and supplemented/POAF patients showed 276 and 170% higher reactive oxygen species (ROS) levels and 223 and 96% higher nitrotyrosine residues levels, respectively, compared to sinus rhythm (SR). In POAF tissue, antioxidant supplementation prevented Cx40 and Cx43 lateralization on cardiomyocyte sarcolemma, keeping them at the intercalated disks. POAF samples showed Cx40 heterogeneous distribution pattern, presenting tissue areas lacking this protein (49 and 55% lower levels in placebo/POAF and supplemented/POAF groups, respectively, compared to SR). Of note, Cx45 overexpression occurred in POAF, being 211 and 167% higher in placebo/POAF and supplemented/POAF groups, respectively, compared to SR. It is concluded that treatment with omega-3 fatty acids and antioxidant vitamins reduces oxidative and nitrosative stress and prevents Cx40/Cx43 lateralization in atrial tissue likely contributing to POAF prevention. However, it failed to fully prevent POAF occurrence because these compounds have no effects on the normalization of Cx40 down-regulation and Cx45 up-regulation, which may promote POAF.
es_ES
Patrocinador
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FONDECYT
1120594
CONICYT
BECAS CHILE
Stiftung William G. Kerckhoff-Herz- und Rheumazentrum, Bad Nauheim, Germany
The effects of polyunsaturated fatty acids and antioxidant vitamins on atrial oxidative stress, nitrotyrosine residues, and connexins following extracorporeal circulation in patients undergoing cardiac surgery