Tanshinone IIA prevents doxorubicin-induced cardiomyocyte apoptosis through Akt-dependent pathway Hong-Jye Hong a , Ju-Chi Liu b , Po-Yuan Chen c , Jin-Jer Chen d,e,f , Paul Chan b,1 , Tzu-Hurng Cheng c, ⁎ ,1 a School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan, ROC b Department of Medicine, Taipei Medical University-Wan Fang Hospital, Taipei, Taiwan, ROC c Department of Biological Science and Technology, College of Life Sciences, China Medical University, Taichung, Taiwan, ROC d Division of Cardiology, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan, ROC e Graduate Institute of Clinical Medical Science, College of Medicine, China Medical University, Taichung, Taiwan, ROC f Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan, ROC abstract article info Article history: Received 15 June 2010 Received in revised form 10 October 2010 Accepted 4 December 2010 Available online 28 December 2010 Keywords: Doxorubicin Tanshinone IIA Traditional Chinese medicine Cardiomyocyte apoptosis Akt Background: Doxorubicin, one of the original anthracyclines, remains among the most effective anticancer drugs ever developed. Clinical use of doxorubicin is, however, greatly limited by its serious adverse cardiac effects that may ultimately lead to cardiomyopathy and heart failure. Tanshinone IIA is the main effective component of Salvia miltiorrhiza known as ‘Danshen’ in traditional Chinese medicine for treating cardiovascular disorders. The objective of this study was set to evaluate the protective effect of tanshinone IIA on doxorubicin-induced cardiomyocyte apoptosis, and to explore its intracellular mechanism(s). Methods: Primary cultured neonatal rat cardiomyocytes were treated with the vehicle, doxorubicin (1 μM), tanshinone IIA (0.1, 0.3, 1 and 3 μM), or tanshinone IIA plus doxorubicin. Results: We found that tanshinone IIA (1 and 3 μM) inhibited doxorubicin-induced reactive oxygen species generation, reduced the quantity of cleaved caspase-3 and cytosol cytochrome c, and increased BcL-x L expression, resulting in protecting cardiomyocytes from doxorubicin-induced apoptosis. In addition, Akt phosphorylation was enhanced by tanshinone IIA treatment in cardiomyocytes. The wortmannin (100 nM), LY294002 (10 nM), and siRNA transfection for Akt significantly reduced tanshinone IIA-induced protective effect. Conclusions: These findings suggest that tanshinone IIA protects cardiomyocytes from doxorubicin-induced apoptosis in part through Akt-signaling pathways, which may potentially protect the heart from the severe toxicity of doxorubicin. © 2010 Elsevier Ireland Ltd. All rights reserved. 1. Introduction Doxorubicin, one of the original anthracyclines and first isolated in the early 1960s, remains among the most effective anticancer drugs ever developed [1]. Clinical use of doxorubicin is, however, greatly limited by its serious adverse cardiac effects that may ultimately lead to cardiomyopathy and heart failure [2]. Among the various mechanisms suggested to mediate doxorubicin's cardiotoxicity, the increased formation of reactive oxygen species (ROS) [3] which ultimately results in cardiomyocyte apoptosis (or programmed cell death) is one of the most plausible [4]. Nevertheless, to date, researchers/scientists have tried out a variety of approaches aimed at preventing or mitigating the deleterious action of doxorubicin, but so far, the ability of these treatments to protect the heart from damage is limited [5]. Therefore, the development of therapies with which to prevent and/or treat the doxorubicin's cardiotoxicity remains a critical issue in both cardiology and oncology. Tanshinone IIA, extracted from Danshen, a popular medicinal herbs used in traditional Chinese medicine, exhibits a variety of cardiovascular activities including vasorelaxation and cardio-protective effects [6–9]. However, the pretreatment effects and mechanisms of tanshinone IIA on cardio-protections are not well understood. Akt is known to regulate many survival pathways of the cardiac cells [10]; and has been reported to preserve cardiac function and prevent cardiac injury [11]. Therefore, the present study was set to evaluate the protective effect of tanshinone IIA on doxorubicin-induced cardiomyocyte apoptosis, and to identify whether the underlying mechanisms are associated with the Akt- dependent pathway. International Journal of Cardiology 157 (2012) 174–179 ⁎ Corresponding author. Tel.: +886 4 22053366x2515; fax: +886 4 22071500. E-mail addresses: chanpaul@wanfang.gov.tw (P. Chan), thcheng@mail.cmu.edu.tw (T.-H. Cheng). 1 These authors codirected the project and contributed equally to the work. 0167-5273/$ – see front matter © 2010 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ijcard.2010.12.012 Contents lists available at ScienceDirect International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard