Department of Pharmacy, University of Salerno, Fisciano (SA) 84084, Italy.
Cardiovascular Diseases Research Group, Department of Cardiology, Vall d'Hebron University Hospital and Research Institute, Universitat Autònoma de Barcelona (UAB), Barcelona 08035, Spain.
Int J Mol Sci. 2017 Oct 11;18(10):2121. doi: 10.3390/ijms18102121.
The use of Doxorubicin (DOXO), a potent antineoplastic agent, is limited by the development of cardiotoxicity. DOXO-induced cardiotoxicity is multifactorial, although alterations in calcium homeostasis, seem to be involved. Since even the Connexin43 (Cx43) plays a pivotal role in these two phenomena, in this study we have analyzed the effects of DOXO on Cx43 expression and localization. Damage caused by anthracyclines on cardiomyocytes is immediate after each injection, in the present study we used a short-term model of DOXO-induced cardiomyopathy. C57BL/6j female mice were randomly divided in groups and injected with DOXO (2 or 10 mg/kg i.p.) for 1-3 or 7 days once every other day. Cardiac function was assessed by Echocardiography. Sarco/endoplasmic reticulum Ca-ATPase (SERCAII) and phospholamban (PLB) expression were assessed by Western blot analysis, intracellular [Ca] were detected spectrofluorometrically by means of Fura-2 pentakis (acetoxymethyl) ester (FURA-2AM), and Cx43 and pCx43 expression and localization was analyzed by Western blot and confirmed by immunofluorescence analysis. DOXO induces impairment in Ca homeostasis, already evident after a single administration, and affects Cx43 expression and localization. Our data suggest that DOXO-induced alterations in Ca homeostasis causes in the cells the induction of compensatory mechanisms until a certain threshold, above which cardiac injury is triggered.
多柔比星（DOXO）是一种有效的抗肿瘤药物，但由于其引发的心脏毒性而限制了其使用。DOXO 诱导的心脏毒性是多因素的，尽管钙稳态的改变似乎与之有关。由于连接蛋白 43（Cx43）在这两种现象中都起着关键作用，因此在本研究中我们分析了 DOXO 对 Cx43 表达和定位的影响。蒽环类抗生素对心肌细胞的损伤是在每次注射后立即发生的，在本研究中，我们使用了 DOXO 诱导的心肌病的短期模型。C57BL/6j 雌性小鼠被随机分为几组，并每隔一天腹腔注射 DOXO（2 或 10mg/kg）1-3 或 7 天。通过超声心动图评估心脏功能。通过 Western blot 分析评估肌浆网/内质网 Ca-ATP 酶（SERCAII）和磷蛋白（PLB）的表达，通过 Fura-2 五乙酸甲酯（FURA-2AM）荧光分光光度法检测细胞内 [Ca]，并通过 Western blot 分析和免疫荧光分析确认 Cx43 和 pCx43 的表达和定位。DOXO 诱导 Ca 稳态的破坏，在单次给药后就已经明显，并且影响 Cx43 的表达和定位。我们的数据表明，DOXO 诱导的 Ca 稳态改变导致细胞中诱导补偿机制，直到达到一定的阈值，超过该阈值就会引发心脏损伤。
