Abstract
Doxorubicin (Dox)-induced cardiotoxicity, usually associated with increased oxidative stress, myofibrillar deterioration, and impaired cardiac contractile function, is a serious complication of antitumor therapy which may not be detected for many years. Growing evidence indicates that the regulation of cardiac microRNA (miRNA, miR) in response to exercise is essentially involved in the protective effect of exercise in the treatment of cardiovascular diseases. However, it is largely unknown whether and how exercise could prevent Dox-induced cardiotoxicity via regulating miRNA biology. In the current study, C57BL/6 mice were either subjected to a 3-week swimming program or remained sedentary. Mice were then treated with Dox (ip. 4 mg/kg/week for 4 weeks) to induce cardiotoxicity. Our data demonstrated that Dox resulted in marked reduction of cardiac ejection fraction (EF, %) and fractional shortening (FS, %) as measured by echocardiography. Interestingly, exercise significantly improved cardiac EF (%) and FS (%) in Dox-treated mice, indicating the protective effect of exercise in Dox-induced cardiotoxicity. Then, we performed microarray analysis (Affymetrix 3.0) showing that miR-27a-5p, miR-34b-3p, miR-185-3p, miR-203-3p, miR-669a-5p, miR-872-3p, and let-7i-3p were significantly reduced, while miR-2137 was increased in the hearts of exercised Dox-treated mice versus sedentary Dox-treated mice (FC(abs)>1.5, p<0.05). Using qRT-PCR, we further verified that miR-669a-5p was reduced by exercise training in Dox-treated mice. These data reveal that miR-669a-5p might be a potential miRNA mimicking the benefit of exercise in Dox-induced cardiotoxicity. Further study is needed to clarify the functional effect of miR-669a-5p and to identify its downstream target gene that contributes to the prevention and treatment of Dox-induced cardiotoxicity.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.