Targeting mitochondrial metabolism for detection and treatment of doxorubicin-induced heart failure

We conducted RNAseq using mRNA extracted from rat hearts to elucidate the effect of doxorubicin chemotherapy on the heart. Rats were 250g at the start of the treatment protocol. Tissues were collected post five weekly intravenous injections of either sterile saline or 3mg/kg/week doxorubicin. Hearts were excised under deep isoflurane anaesthesia and rapidly frozen with liquid-nitrogen cooled Wallenberger tongs. Total mRNA was extracted with a Qiagen RNeasy fibrous tissue mini kit. Gene set enrichement analysis (GSEA) shows that unlike previously reported, oxidative stress is not involved in the cardiac pathology of our model (reduced cardiac function and atrophy). However, gene sets responsible for mRNA processing, ribosomes and protein synthesis and processing are decreased in doxorubicin-treated rat hearts compared to saline control hearts. Overall design: 16 RNASeq samples across 2 conditions: saline control (n=10) and high DOX (n=6)

本研究使用从大鼠心脏中提取的信使RNA（mRNA）进行RNA测序（RNAseq），以阐明阿霉素化疗对心脏的影响。实验初始时，大鼠体重为250g。实验方案为每周经静脉注射给药1次，共给药5次，实验组给予3mg/kg/周的阿霉素，对照组则注射无菌生理盐水，完成全部给药后采集组织样本。所有大鼠均在深度异氟烷麻醉下摘除心脏，随后使用经液氮预冷的瓦伦贝格镊子（Wallenberger tongs）快速冷冻心脏样本。总mRNA使用凯杰（Qiagen）RNeasy纤维组织迷你试剂盒提取。基因集富集分析（Gene Set Enrichment Analysis, GSEA）结果显示，与既往研究报道不同，氧化应激并未参与本模型的心脏病理过程（心脏功能减退与心肌萎缩）。然而，与生理盐水对照组大鼠心脏相比，阿霉素处理组大鼠心脏中负责mRNA加工、核糖体及蛋白质合成与加工的基因集表达水平显著下调。实验整体设计：共包含16个RNA测序（RNAseq）样本，分为2组：生理盐水对照组（n=10）与高剂量阿霉素组（n=6）。