Mechanisms of Paeoniflorin against myocardial ischemia reperfusion injury based on network pharmacology

Ischemic heart disease (IHD) is the primary reason of death of cardiovascular diseases. Paeoniflorin (PF), a monoterpene glycoside extracted from Radix Paeoniae Rubra or Paeoniae Radix Alba, can ameliorate myocardial ischemia/reperfusion injury (MIRI), but its mechanism is not still defined. In this study, network pharmacology was utilized, the protein interaction network between PF and MIRI targets were screened for bioenrichment analysis. Moreover, the anti-MIRI effects of PF (30, 60 and 120 mg/kg) were investigated in vivo on rats for verification. The myocardial infarction area was assessed by TTC/Evans blue staining and morphological changes of tissues were evaluated using hematoxylin and eosin staining. The contents of myocardial enzymes and oxidation resistance were measured. The cell apoptosis was evaluated using TUNEL staining and the expression of proteins was estimated using Western Blot. In the results, the relevant targets and the biological processes of PF against MIRI were screened out, indicating its anti-MIRI potential pharmacological effects of PF. 120 mg/kg PF can shrink infarction area after ischemia/reperfusion, ameliorate pathological morphology in myocardial tissue, lower the levels of myocardial enzymes, and attenuate oxidative stress. Furthermore, PF could reduce the positive rate of TUNEL staining caused by MIRI. Moreover, 120 mg/kg PF could depress the protein levels of Bax, Caspase-3, Beclin-1 and Cathepsin B and increase the protein level of Bcl-2 on rats after reperfusion. In conclusion, Paeoniflorin has an anti-MIRI effect in rats via coordinate regulation of anti-oxidative stress, anti-apoptosis and inhibition of autophagy.