All submissions of the EM system will be redirected to Online Manuscript Submission System. Authors are requested to submit articles directly to Online Manuscript Submission System of respective journal.

Protective role of neuregulin-1 toward doxorubicin-induced myocardial toxicity

Author(s): Y.Q. Liu, M. Yang, C.H. Duan, G.B. Su, J.H. Wang, Y.F. Liu and J. Zhang

The aim of this study was to investigate the role of the rat neuregulin-1 (NRG-1) protein in reducing doxorubicin (DOX)-induced myocardial toxicity and its underlying mechanism. The prokaryotic expression of the NRG-1 protein and the CCK8-determined activity of rat primary myocardial cells were evaluated under different DOX concentrations. Myocardial cells were divided into three groups: the control group, the 5 μM DOX (DOX5) group, and the DOX5 + NRG-1 group. Western blotting was used to determine the Na+-Ca2+ exchanger (NCX-1) and cardiac myosin light-chain kinase (cMLCK) protein expression levels and real-time quantitative polymerase chain reaction methods were used to determine the mRNA expression levels. The prokaryotic expression of NRG-1 in the DOX5 group produced toxicity in the rat myocardial cells, and cell activity was significantly restored with the addition of NRG-1. The protective effect of NRG-1 was limited at higher DOX concentrations (DOX10), and the degree of cellular activity restoration was positively correlated with NRG-1 concentration. The addition of NRG-1 to DOX5 intervention inhibited NCX-1 protein and mRNA expression, and increased cMLCK protein and mRNA expression. In conclusion, DOX-induced toxicity in rat myocardial cells could be protected by NRG-1, and the mechanism may be related to the role of NRG-1 in up-regulating the cMLCK expression level and down-regulating the NCX-1 expression level.