Book of Abstracts - New Frontiers 2022

Abstracts of poster presentations

EFFECT OF OMACOR AGAINST THE INCREASED INCIDENCE OF MALIGNANT CARDIAC ARRHYTHMIAS TRIGGERED BY LIGHT POLLUTION B. Szeiffova Bacova 1 , T. Egan Benova 1 , M. Sykora 1 , J. Zurmanova 2 , V. Knezl 1 , K. Andelova 1 , N. Tribulova 1 1 Center of Experimental Medicine, Slovak Academy of Sciences, Bratislava, Slovakia; 2 Department of Physiology, Faculty of Science, Charles University, Prague, Czech Republic Objective Light pollution disturbs circadian rhythm and increases susceptibility to arrhythmias. Our aim was to determine whether rats exposed to continuous light will have altered myocardial gene transcripts/protein expression implicated in arrhythmogenesis as well as to assess Omacor supplementation on these changes. Design and method We used in the experiment male and female spontaneously hypertensive (SHR) and normotensive Wistar rats (WR) housed under standard 12 h/12 h light/dark cycles or exposed to 6-weeks continuous 300 lux light for 24 h. Half the rats were treated with 200 mg/100 g b.w. Omacor. Results Continuous light resulted in higher male rat vulnerability to malignant ventricular fibrillation (VF). It was associated with myocardial connexin-43 (Cx43) down-regulation and worsen intercellular electrical coupling, due to increased pro-inflammatory NF-kB and iNOS transcripts and decreased sarcoplasmic reticulum Ca 2+ ATPase transcripts. Omacor supplementation increased the electrical threshold to induce the VF linked with amelioration of myocardial Cx43 mRNA and Cx43 protein levels and the suppression of NF-kB and iNOS. It can be concluded that rat exposure to continuous light outcomes deleterious cardiac alterations jeopardizing intercellular Cx43 channel-mediated electrical communication, thereby increasing the risk of malignant arrhythmias. Conclusions The adverse effects were attenuated by treatment with Omacor, thus supporting its potential benefit and the relevance of monitoring the omega-3 index in human populations at risk.

Keywords: Omacor; light pollution; rats; cardiac arrhythmias; connexin-43; NF- κB; iNOS

Funding:This research was supported by Slovak VEGA 2/0002/20, 2/0158/19, APVV 18-0548, 19 0317 and EU ITMS 26230120009.

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