Protective Effects of Achillea millefolium Extract on Myocardial Infarction Induced by Isoproterenol in Rats

Background and purpose: In recent years, natural products have been widely used in traditional medicine to treat cardiovascular diseases. The aim of this study was to determine the cardioprotective effect of Achillea millefolium extract against isoproterenol (ISO) induced myocardial infarction (MI) in rats. Materials and methods: In this experimental study, the aerial parts of the plant were extracted with ethanol through maceration and subjected to colorimetry to determine flavonoids and phenolic compounds. The rats were treated with A.millefolium (100, 200, 400 mg/kg) for 14 days. MI was induced by intraperitoneal injection of isoproterenol (85 mg/kg) at days 15 and 16. Twenty-four hours after the second dose of ISO injection, the rats were anaesthetized and electrocardiographic (ECG) parameters were recorded and blood samples were obtained for biochemical assay. Results: Isoproterenol increased heart weight/body weight ratio, serum levels of CK-MB, LDH, MDA, and decreased serum levels of total antioxidant capacity. In addition, it produced ST-segment elevation, decreased R-wave amplitude, and increased QT interval and heart rate. Pretreatment with A. millefolium at different doses prevented ISO-induced changes. Phenolic and flavonoid contents were 57.37 mg gallic acid/g DW and 6.74 mg quercetin /g DW, respectively. The IC50 value of the extract was 81.54 μg/ ml in DPPH method. Conclusion: The study showed that yarrow extract (A. millefolium) with its antioxidant properties protects the heart from ischemic damage caused by isoproterenol.