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

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.

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.

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).

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.