Background: Acute myocardial infarction (AMI) is a common cardiovascular disease in clinic. Currently, there is no specific treatment for AMI. Carbon dots (CDs) have been reported to show excellent biological activities, which hold promise for the development of novel nanomedicines for the treatment of cardiovascular diseases. Methods: In this study, we firstly prepared CDs from the natural herb Curcumae Radix Carbonisata (CRC-CDs) by a green, simple calcination method. The aim of this study is to investigate the cardioprotective effect and mechanism of CRC-CDs on isoproterenol (ISO) -induced myocardial infarction (MI) in rats.
Results:The results showed that pretreatment with CRC-CDs significantly reduced serum levels of cardiac enzymes (CK-MB, LDH, AST) and lipids (TC, TG, LDL) and reduced st-segment elevation and myocardial infarct size on the ECG in AMI rats. Importantly, cardiac ejection fraction (EF) and shortening fraction (FS) were markedly elevated, as was ATPase activity. In addition, CRC-CDs could significantly increase the levels of superoxide dismutase (SOD), reduced glutathione (GSH), catalase (CAT), and reduce the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) in myocardial tissue, thereby exerting cardioprotective effect by enhancing the antioxidant capacity of myocardial tissue. Moreover, the TUNEL staining image showed that positive apoptotic cells were markedly declined after CRC-CDs treatment, which indicate that CRC-CDs could inhibit cardiomyocyte apoptosis. Importantly, The protective effect of CRC-CDs on H 2 O 2 -pretreated H9c2 cells was also verified in vitro. Conclusion: Taken together, CRC-CDs has the potential for clinical application as an anti-myocardial ischemia drug candidate, which not only provides evidence for further broadening the biological application of cardiovascular diseases, but also offers potential hope for the application of nanomedicine to treat intractable diseases.