Department of Physiology, Faculty of Veterinary Medicine, University of Erciyes, 38039, Kayseri, Turkey.
Exp Physiol. 2019 Apr;104(4):505-513. doi: 10.1113/EP086739. Epub 2019 Feb 27.
What is the central question of this study? The study was designed to assess whether pretreatment with β-glucan could exert any protective action against isoprenaline-induced myocardial injury in rats. What is the main finding and its importance? β-Glucan pretreatment could reduce myocardial injury by restoring cardiac biomarkers, antioxidant status, apoptosis and histopathological changes. Therefore, β-glucan might have the potential to be used in the prevention and/or treatment of myocardial infarction.
This study was designed to investigate the cardioprotective effect of pretreatment with β-glucan, the glucose polymer derived from the yeast Saccharomyces cerevisiae, against isoprenaline (ISO)-induced myocardial injury in rats by studying biochemical cardiac markers, antioxidant parameters, apoptosis, ECG and histopathological changes. Male Sprague-Dawley rats were randomly divided into four treatment groups, namely control, β-glucan, isoprenaline and β-glucan + isoprenaline. The β-glucan treatment group received β-glucan (50 mg kg day , p.o.) for 10 days. Myocardial injury was induced by ISO administration (100 mg kg , s.c.) twice, at an interval of 24 h, on the 9th and 10th days. Isoprenaline administration resulted in a marked increase in heart rate, ST segment elevation, myocardial malondialdehyde content, cardiac marker levels (lactate dehydrogenase, creatine kinase-MB and high-sensitivity cardiac troponin T) and apoptotic index, and a significant decrease in R-wave amplitude and myocardial superoxide dismutase, catalase and glutathione peroxidase activities. In addition, apoptosis, congestion, necrosis, inflammatory cell infiltration and myofibrillar disorganization were observed histologically in myocardial tissue sections. The oral pretreatment with β-glucan prevented almost all the parameters of isoprenaline-induced myocardial injury in rats, and these findings were confirmed by the histopathological analysis. These findings provide evidence that β-glucan could protect rat myocardium against ISO-induced myocardial injury, and this was attributed to its antioxidant and anti-apoptotic properties.
本研究的核心问题是什么？本研究旨在评估预处理β-葡聚糖是否对大鼠异丙肾上腺素诱导的心肌损伤具有保护作用。主要发现及其重要性是什么？β-葡聚糖预处理可通过恢复心脏生物标志物、抗氧化状态、细胞凋亡和组织病理学变化来减轻心肌损伤。因此，β-葡聚糖可能具有用于预防和/或治疗心肌梗死的潜力。
本研究旨在通过研究生化心脏标志物、抗氧化参数、细胞凋亡、心电图和组织病理学变化，探讨酵母葡聚糖（β-葡聚糖）预处理对大鼠异丙肾上腺素（ISO）诱导的心肌损伤的心脏保护作用。雄性 Sprague-Dawley 大鼠随机分为四组，即对照组、β-葡聚糖组、ISO 组和β-葡聚糖+ISO 组。β-葡聚糖处理组连续 10 天每天口服 50mg/kgβ-葡聚糖。第 9 天和第 10 天，ISO 以 100mg/kg，皮下注射两次，两次间隔 24 小时，诱导心肌损伤。ISO 给药导致心率、ST 段抬高、丙二醛含量、心脏标志物水平（乳酸脱氢酶、肌酸激酶同工酶-MB 和高敏心肌肌钙蛋白 T）和细胞凋亡指数显著增加，R 波振幅和心肌超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶活性显著降低。此外，心肌组织切片中观察到细胞凋亡、充血、坏死、炎症细胞浸润和肌原纤维紊乱。β-葡聚糖的口服预处理几乎可预防大鼠 ISO 诱导的所有心肌损伤参数，组织病理学分析证实了这一点。这些发现提供了证据表明，β-葡聚糖可以保护大鼠心肌免受 ISO 诱导的心肌损伤，这归因于其抗氧化和抗细胞凋亡特性。
