Journal of Environmental Science and Health, Part A ( IF 2.1 ) Pub Date : 2021-03-15 , DOI: 10.1080/10934529.2021.1899534 Sandra Arbi 1 , Megan Jean Bester 1 , Liselle Pretorius 1 , Hester Magdalena Oberholzer 1
Abstract
The aim of this study was to identify cardiovascular effects of relevant concentrations of Cd and Hg alone and in combination as a mixture in water. This was achieved by administering to male Sprague–Dawley rats via gavage 0.62 mg/kg Cd or 1.23 mg/kg Hg, or a combination of 0.62 mg/kg Cd and 1.23 mg/kg Hg in the co-exposure group for 28 days. Concentrations were the rat equivalence dosages of 1,000 times the World Health Organization’s limits of 0.003 mg/L and 0.006 mg/L for Cd and Hg, respectively, for water. With termination, blood levels of the metals were increased. For all metal exposed groups, histological evaluation and transmission electron microscopy of the myocardium revealed myofibrillar necrosis, increased fibrosis, vacuole formation and mitochondrial damage. Cd caused the most mitochondrial damage while Hg to a greater degree induced fibrosis. In the aorta, both Cd and Hg also increased collagen deposition adversely altering the morphology of the fenestrated elastic fibers in the tunica media. Co-exposure resulted in increased cardiotoxicity with increased mitochondrial damage, fibrosis and distortion of the aortic wall as a result of increased collagen deposition, as well as altered elastin deposition, fragmentation and interlink formation. These are typical features of oxidative damage that correlates with a phenotype of premature ageing of the CVS that potentially can lead to hypertension and premature cardiac failure.
中文翻译:
单独接触镉和汞以及联合接触镉和汞对 Sprague-Dawley 大鼠心脏组织和主动脉的不良心血管影响
摘要
本研究的目的是确定相关浓度的 Cd 和 Hg 单独和混合作为水中混合物对心血管的影响。这是通过给雄性 Sprague-Dawley 大鼠灌胃 0.62 mg/kg Cd 或 1.23 mg/kg Hg,或 0.62 mg/kg Cd 和 1.23 mg/kg Hg 的组合在共同暴露组中给药 28 天来实现的。浓度是大鼠等效剂量的 1,000 倍世界卫生组织对水的镉和汞的限值分别为 0.003 毫克/升和 0.006 毫克/升。随着终止,血液中的金属含量增加。对于所有金属暴露组,心肌的组织学评估和透射电子显微镜显示肌原纤维坏死、纤维化增加、空泡形成和线粒体损伤。Cd 引起的线粒体损伤最大,而 Hg 引起的纤维化程度更高。在主动脉中,Cd 和 Hg 也增加了胶原沉积,不利地改变了中膜中开孔弹性纤维的形态。由于胶原蛋白沉积增加以及弹性蛋白沉积、碎裂和互连形成的改变,共同暴露导致心脏毒性增加,线粒体损伤、纤维化和主动脉壁变形增加。这些是氧化损伤的典型特征,与 CVS 过早老化的表型相关,可能导致高血压和过早心脏衰竭。由于胶原蛋白沉积增加以及弹性蛋白沉积、碎裂和互连形成的改变,共同暴露导致心脏毒性增加,线粒体损伤、纤维化和主动脉壁变形增加。这些是氧化损伤的典型特征,与 CVS 过早老化的表型相关,可能导致高血压和过早心脏衰竭。由于胶原蛋白沉积增加以及弹性蛋白沉积、碎裂和互连形成的改变,共同暴露导致心脏毒性增加,线粒体损伤、纤维化和主动脉壁变形增加。这些是氧化损伤的典型特征,与 CVS 过早老化的表型相关,可能导致高血压和过早心脏衰竭。