Proteomic study of Tianxiangdan intervention in rats with myocardial ischemia

The present study aimed to screen out the proteins with significantly differential expression through the proteomics study of Tianxiangdan intervention in rats with myocardial ischemia as well as elucidate the mechanism of the intervention. In total, 54 Wistar rats (male, 6-8 weeks old) were randomly divided into the blank group, sham operation group, and model group, with 6 rats in each, together with the model + low dose group, model + medium-dose group, and model + high dose group, with 12 rats in each. Upon successful construction of the ischemic model, low, medium, and high doses, respectively, of Tianxiangdan were administered in the groups. The rat model of coronary heart disease (CHD) with myocardial ischemia was prepared by ligating the coronary artery. The tandem mass tag-labeled quantitative proteomics technology was adopted to observe the differentially expressed proteins in the myocardium of the model rats under the action of Tianxiangdan to find the target proteins for the treatment of myocardial ischemia in CHD. A total of 3122 proteins were identified. Combined with the references, tropomyosin alpha-3 chain (TPM3), protein kinase C delta (PRKCD), myosin heavy chain 10 (MYH10), MYH6, G protein subunit alpha i2 (GNAI2), and other proteins were screened out. Western blotting was adopted for the proteomics validation, and it was found that compared with the sham operation group, the expression levels of the GNAI2, TPM3, and MYH10 proteins were upregulated in the myocardial ischemia model group but downregulated after the administration of Tianxiangdan; the differences were statistically significant (p<0.05). We conclude that Tianxiangdan could improve myocardial ischemia by downregulating the proteins, including GNAI2, TPM3, and MYH10, which might be potential targets of Tianxiangdan in the treatment of myocardial infarction.