Pavel Vebr, Frantisek Galatík, Aneta Marvanova, Barbara Elsnicova, Daniela Hornikova, Marek Vecka, Sarka Spinova, Olga Novakova, Jitka M Zurmanova
{"title":"长期暴露于中等低温环境可降低大鼠再灌注心律失常的发生率。","authors":"Pavel Vebr, Frantisek Galatík, Aneta Marvanova, Barbara Elsnicova, Daniela Hornikova, Marek Vecka, Sarka Spinova, Olga Novakova, Jitka M Zurmanova","doi":"10.1152/japplphysiol.00509.2025","DOIUrl":null,"url":null,"abstract":"<p><p>Recently, moderate cold acclimation (9 °C; MCA) was found to exert cardioprotective effects by increasing resistance to ischemia-reperfusion (IR) injury and mitochondrial calcium overload in rats, but the effect of MCA on the incidence of IR arrhythmias is not known. The aim of this study was to determine whether MCA can induce an anti-arrhythmic effect and, if so, to elucidate a possible mechanism. Adult male Wistar rats were acclimated (9 °C) for short (1-3-10 days) and long-term (5 weeks; CA) periods, followed by a two-week recovery period (24 °C; CAR). The number of premature ventricular complexes (PVCs) and their duration after IR, western blotting, thin layer and gas chromatography were performed on left ventricular myocardium. We revealed that total reperfusion PVCs and tachyarrhythmia duration decreased even after CA, and accordingly the anti-arrhythmic n-3PUFAs increased in cardiac membrane phospholipids, the n-6/n-3 PUFA ratio decreased. CA increased the distribution of connexin 43 (Cx43) in favor of end-to-end junctions and the expression of uncoupling protein UCP3 in mitochondria. These beneficial effects were lost after two-weeks recovery period CAR. Interestingly, the mitochondrial antioxidants superoxide dismutase (SOD2) and thioredoxin reductase (TRXRD2) were strongly upregulated exclusively after 1 day of cold exposure, whereas cytosolic TRXRD1 was downregulated. In conclusion, long-term MCA (5-weeks) reduces the incidence of reperfusion arrhythmias, increases the proportion of anti-arrhythmic n-3PUFAs in cardiomyocyte membranes and has a positive effect on Cx43 distribution. By increasing the amount of UCP3 in mitochondria, it may reduce the likelihood of free radical formation in mitochondria during reperfusion.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3000,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Long-term exposure to moderate cold reduces incidence of reperfusion tachyarrhythmias in rats.\",\"authors\":\"Pavel Vebr, Frantisek Galatík, Aneta Marvanova, Barbara Elsnicova, Daniela Hornikova, Marek Vecka, Sarka Spinova, Olga Novakova, Jitka M Zurmanova\",\"doi\":\"10.1152/japplphysiol.00509.2025\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Recently, moderate cold acclimation (9 °C; MCA) was found to exert cardioprotective effects by increasing resistance to ischemia-reperfusion (IR) injury and mitochondrial calcium overload in rats, but the effect of MCA on the incidence of IR arrhythmias is not known. The aim of this study was to determine whether MCA can induce an anti-arrhythmic effect and, if so, to elucidate a possible mechanism. Adult male Wistar rats were acclimated (9 °C) for short (1-3-10 days) and long-term (5 weeks; CA) periods, followed by a two-week recovery period (24 °C; CAR). The number of premature ventricular complexes (PVCs) and their duration after IR, western blotting, thin layer and gas chromatography were performed on left ventricular myocardium. We revealed that total reperfusion PVCs and tachyarrhythmia duration decreased even after CA, and accordingly the anti-arrhythmic n-3PUFAs increased in cardiac membrane phospholipids, the n-6/n-3 PUFA ratio decreased. CA increased the distribution of connexin 43 (Cx43) in favor of end-to-end junctions and the expression of uncoupling protein UCP3 in mitochondria. These beneficial effects were lost after two-weeks recovery period CAR. Interestingly, the mitochondrial antioxidants superoxide dismutase (SOD2) and thioredoxin reductase (TRXRD2) were strongly upregulated exclusively after 1 day of cold exposure, whereas cytosolic TRXRD1 was downregulated. In conclusion, long-term MCA (5-weeks) reduces the incidence of reperfusion arrhythmias, increases the proportion of anti-arrhythmic n-3PUFAs in cardiomyocyte membranes and has a positive effect on Cx43 distribution. By increasing the amount of UCP3 in mitochondria, it may reduce the likelihood of free radical formation in mitochondria during reperfusion.</p>\",\"PeriodicalId\":15160,\"journal\":{\"name\":\"Journal of applied physiology\",\"volume\":\" \",\"pages\":\"\"},\"PeriodicalIF\":3.3000,\"publicationDate\":\"2025-09-23\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of applied physiology\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://doi.org/10.1152/japplphysiol.00509.2025\",\"RegionNum\":3,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"PHYSIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of applied physiology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1152/japplphysiol.00509.2025","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PHYSIOLOGY","Score":null,"Total":0}
Long-term exposure to moderate cold reduces incidence of reperfusion tachyarrhythmias in rats.
Recently, moderate cold acclimation (9 °C; MCA) was found to exert cardioprotective effects by increasing resistance to ischemia-reperfusion (IR) injury and mitochondrial calcium overload in rats, but the effect of MCA on the incidence of IR arrhythmias is not known. The aim of this study was to determine whether MCA can induce an anti-arrhythmic effect and, if so, to elucidate a possible mechanism. Adult male Wistar rats were acclimated (9 °C) for short (1-3-10 days) and long-term (5 weeks; CA) periods, followed by a two-week recovery period (24 °C; CAR). The number of premature ventricular complexes (PVCs) and their duration after IR, western blotting, thin layer and gas chromatography were performed on left ventricular myocardium. We revealed that total reperfusion PVCs and tachyarrhythmia duration decreased even after CA, and accordingly the anti-arrhythmic n-3PUFAs increased in cardiac membrane phospholipids, the n-6/n-3 PUFA ratio decreased. CA increased the distribution of connexin 43 (Cx43) in favor of end-to-end junctions and the expression of uncoupling protein UCP3 in mitochondria. These beneficial effects were lost after two-weeks recovery period CAR. Interestingly, the mitochondrial antioxidants superoxide dismutase (SOD2) and thioredoxin reductase (TRXRD2) were strongly upregulated exclusively after 1 day of cold exposure, whereas cytosolic TRXRD1 was downregulated. In conclusion, long-term MCA (5-weeks) reduces the incidence of reperfusion arrhythmias, increases the proportion of anti-arrhythmic n-3PUFAs in cardiomyocyte membranes and has a positive effect on Cx43 distribution. By increasing the amount of UCP3 in mitochondria, it may reduce the likelihood of free radical formation in mitochondria during reperfusion.
期刊介绍:
The Journal of Applied Physiology publishes the highest quality original research and reviews that examine novel adaptive and integrative physiological mechanisms in humans and animals that advance the field. The journal encourages the submission of manuscripts that examine the acute and adaptive responses of various organs, tissues, cells and/or molecular pathways to environmental, physiological and/or pathophysiological stressors. As an applied physiology journal, topics of interest are not limited to a particular organ system. The journal, therefore, considers a wide array of integrative and translational research topics examining the mechanisms involved in disease processes and mitigation strategies, as well as the promotion of health and well-being throughout the lifespan. Priority is given to manuscripts that provide mechanistic insight deemed to exert an impact on the field.