Mechanism of curcumin against myocardial ischaemia-reperfusion injury based on the P13K/Akt/mTOR signalling pathway.

OBJECTIVE: To investigate the pharmacodynamic mechanism of curcumin against myocardial ischaemia-reperfusion injury by regulating the phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT)/rapamycin target protein (mTOR) signalling pathway.

MATERIALS AND METHODS: The left anterior descending coronary artery was ligated for 30 min and reperfused for 3 h to establish an ischaemia-reperfusion injury model. The electrocardiogram (ECG) detection of rats was performed, and the degree of myocardial infarction was determined by 2,3,5-triphenyltetrazolium chloride staining. The expression levels of serum creatine kinase isoenzyme (CK), lactate dehydrogenase (LDH), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), nitric oxide (NO) and other related indicators were detected. The protein expressions of mTOR, phosphorylated (p)-mTOR, AKT and p-AKT were detected by Western blotting, whereas the expressions of Bcl-2 and Bax were detected by real-time polymerase chain reaction.

RESULTS: The results showed that compared with the model group, curcumin could improve the ECG findings, reduce the scope of myocardial infarction, reduce the expression levels of CK-MB, LDH, AST, MDA, NO and increase those of SOD and GSH. Curcumin can also down-regulate the expression of Bax and up-regulate the protein levels of Bcl2, p-mTOR and p-AKT (p < 0.05 or p < 0.01).

CONCLUSIONS: This study shows that curcumin has a significant protective effect on myocardial ischaemia-reperfusion, and its mechanism may be related to the activation of PI3K/AKT/mTOR signalling pathway and inhibition of inflammation, apoptosis and oxidative stress.