Department of Internal Medicine, the Affiliated Zhongshan Hospital of Dalian University, Dalian, 116001, Liaoning, PR China.
Preventive Medicine Laboratory, College of Public Health, Dalian Medical University, No.9, West Segment of South lvshun Road, Dalian 116044, Liaoning, PR China; Natural Products Engineering Technology Center, Dalian Medical University, No.9, West Segment of South lvshun Road, Dalian, 116044, Liaoning, PR China.
Toxicology. 2019 Sep 1;425:152238. doi: 10.1016/j.tox.2019.152238. Epub 2019 Jun 18.
The cardiotoxicity of doxorubicin (DOX) limits its clinical use in the treatment of a variety of solid tumors and malignant hematologic disease. However, the mechanism by which it causes cardiotoxicity is not fully understood. Apoptosis has been regarded as one of mechanisms underlying the cardiotoxic effects of DOX. In our study, we found that treatment of human umbilical vein endothelial cells (HUVECs) with DOX induced autophagy and apoptosis in a dose- and time-dependent manner. Treatment with DOX induced autophagy at earlier time (3 h), then lysosomal membrane permeabilization (LMP) altered after treatment for 12 h which followed by the release of cathepsin D (CTSD). Lysosome-associated membrane proteins-1 and -2 (LAMP1 and LAMP2) were decreased in DOX-treated cells. Additionally, DOX induced the collapse of mitochondrial transmembrane potential, reduction of translocase of the outer mitochondrial membrane-20 (TOM-20), and release of cytochrome c. Furthermore, autophagy inhibitor 3-MA relieved DOX-induced apoptosis as assessed by the expression of cleaved caspase-3, cleaved caspase-9 and TUNEL assay. CTSD inhibitor, pepstatin A, upregulated TOM-20 and suppressed the mitochondria release of cytochrome c as well as apoptosis under DOX stress. Pyrroloquinoline quinine (PQQ), a new B vitamin, ameliorated aforementioned phenomenon. In conclusion, our results suggested that DOX-induced apoptosis was autophagy-dependent via lysosomal-mitochondrial axis. PQQ had an ability to protect cell from autophagy-dependent apoptosis induced by DOX via lysosomal-mitochondrial axis to some extent. This study provided new mechanistic insight toward understanding the pathogenesis of DOX-induced cardiotoxicity and the protection effect of PQQ.
阿霉素（DOX）的心脏毒性限制了其在治疗多种实体瘤和恶性血液病中的临床应用。然而，其导致心脏毒性的机制尚不完全清楚。细胞凋亡已被认为是 DOX 心脏毒性作用的机制之一。在我们的研究中，我们发现 DOX 处理人脐静脉内皮细胞（HUVEC）会导致自噬和凋亡，呈剂量和时间依赖性。DOX 处理早期（3 h）诱导自噬，然后在处理 12 h 后溶酶体膜通透性（LMP）改变，随后组织蛋白酶 D（CTSD）释放。溶酶体相关膜蛋白-1 和 -2（LAMP1 和 LAMP2）在 DOX 处理的细胞中减少。此外，DOX 诱导线粒体跨膜电位崩溃，外线粒体膜转位酶 20（TOM-20）减少，细胞色素 c 释放。此外，自噬抑制剂 3-MA 通过检测 cleaved caspase-3、cleaved caspase-9 和 TUNEL 测定法减轻了 DOX 诱导的凋亡。CTSD 抑制剂胃蛋白酶抑制剂 A 上调了 TOM-20，并抑制了 DOX 应激下线粒体细胞色素 c 的释放以及凋亡。吡咯喹啉醌（PQQ），一种新的 B 族维生素，改善了上述现象。总之，我们的结果表明，DOX 诱导的凋亡是通过溶酶体-线粒体轴的自噬依赖性的。PQQ 通过溶酶体-线粒体轴在一定程度上具有保护细胞免受 DOX 诱导的自噬依赖性凋亡的能力。本研究为理解 DOX 诱导的心脏毒性的发病机制和 PQQ 的保护作用提供了新的机制见解。
