Cardioprotective and nonprotective regimens of chronic hypoxia diversely affect the myocardial antioxidant systems

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F75010330%3A_____%2F15%3A00011092" target="_blank" >RIV/75010330:_____/15:00011092 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985823:_____/15:00451957 RIV/00216208:11310/15:10316367

Výsledek na webu

<a href="http://physiolgenomics.physiology.org/content/47/12/612" target="_blank" >http://physiolgenomics.physiology.org/content/47/12/612</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1152/physiolgenomics.00058.2015" target="_blank" >10.1152/physiolgenomics.00058.2015</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Cardioprotective and nonprotective regimens of chronic hypoxia diversely affect the myocardial antioxidant systems

Popis výsledku v původním jazyce

It has been documented that adaptation to hypoxia increases myocardial tolerance to ischemia-reperfusion (I/R) injury depending on the regimen of adaptation. Reactive oxygen species (ROS) formed during hypoxia play an important role in the induction of protective cardiac phenotype. On the other hand, the excess of ROS can contribute to tissue damage caused by I/R. Here we investigated the relationship between myocardial tolerance to I/R injury and transcription activity of major antioxidant genes, transcription factors, and oxidative stress in three different regimens of chronic hypoxia. Adult male Wistar rats were exposed to continuous normobaric hypoxia (FIO2 0.1) either continuously (CNH) or intermittently for 8 h/day (INH8) or 23 h/day (INH23) for 3 wk period. A control group was kept in room air. Myocardial infarct size was assessed in anesthetized open-chest animals subjected to 20 min coronary artery occlusion and 3 h reperfusion. Levels of mRNA transcripts and the ratio of reduced and oxidized glutathione (GSH/GSSG) were analyzed by real-time RT-PCR and by liquid chromatography, respectively. Whereas CNH as well as INH8 decreased infarct size, 1 h daily reoxygenation (INH23) abolished the cardioprotective effect and decreased GSH/GSSG ratio. The majority of mRNAs of antioxidant genes related to mitochondrial antioxidant defense (manganese superoxide dismutase, glutathione reductase, thioredoxin/thioredoxin reductase, and peroxiredoxin 2) were upregulated in both cardioprotective regimens (CNH, INH8). In contrast, INH23 increased only PRX5, which was not sufficient to induce the cardioprotective phenotype. Our results suggest that the increased mitochondrial antioxidant defense plays an important role in cardioprotection afforded by chronic hypoxia.

Název v anglickém jazyce

Cardioprotective and nonprotective regimens of chronic hypoxia diversely affect the myocardial antioxidant systems

Popis výsledku anglicky

It has been documented that adaptation to hypoxia increases myocardial tolerance to ischemia-reperfusion (I/R) injury depending on the regimen of adaptation. Reactive oxygen species (ROS) formed during hypoxia play an important role in the induction of protective cardiac phenotype. On the other hand, the excess of ROS can contribute to tissue damage caused by I/R. Here we investigated the relationship between myocardial tolerance to I/R injury and transcription activity of major antioxidant genes, transcription factors, and oxidative stress in three different regimens of chronic hypoxia. Adult male Wistar rats were exposed to continuous normobaric hypoxia (FIO2 0.1) either continuously (CNH) or intermittently for 8 h/day (INH8) or 23 h/day (INH23) for 3 wk period. A control group was kept in room air. Myocardial infarct size was assessed in anesthetized open-chest animals subjected to 20 min coronary artery occlusion and 3 h reperfusion. Levels of mRNA transcripts and the ratio of reduced and oxidized glutathione (GSH/GSSG) were analyzed by real-time RT-PCR and by liquid chromatography, respectively. Whereas CNH as well as INH8 decreased infarct size, 1 h daily reoxygenation (INH23) abolished the cardioprotective effect and decreased GSH/GSSG ratio. The majority of mRNAs of antioxidant genes related to mitochondrial antioxidant defense (manganese superoxide dismutase, glutathione reductase, thioredoxin/thioredoxin reductase, and peroxiredoxin 2) were upregulated in both cardioprotective regimens (CNH, INH8). In contrast, INH23 increased only PRX5, which was not sufficient to induce the cardioprotective phenotype. Our results suggest that the increased mitochondrial antioxidant defense plays an important role in cardioprotection afforded by chronic hypoxia.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

FA - Kardiovaskulární nemoci včetně kardiochirurgie

OECD FORD obor

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Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

V - Vyzkumna aktivita podporovana z jinych verejnych zdroju

Rok uplatnění

2015

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physiological Genomics

ISSN

1094-8341

e-ISSN

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Svazek periodika

47

Číslo periodika v rámci svazku

12

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

9

Strana od-do

612-620

Kód UT WoS článku

000365900400004

EID výsledku v databázi Scopus

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