Investigating the mechanism of action of Danhong injection and its components against myocardial ischemia–reperfusion injury

Objective: The surgical treatment of myocardial infarction often causes myocardial ischemia–reperfusion injury (MI/RI). Danhong injection (DHI) has curative effects on coronary heart disease and angina pectoris. However, its therapeutic effects on MI/RI still require further validation. This study aims to investigate the components involved and mechanism of action of DHI against MI/RI. Methods: Primary metabolites (PM) and secondary metabolites (SM) were isolated from DHI. We established a rat model of MI/RI by administering PM, SM, and DHI. Cardiac morphology and functional parameters were evaluated using cardiac ultrasound. The metabolic effects of PM, SM, and DHI in the serum and myocardial tissue on MI/RI were investigated using 1hydrogen-nuclear magnetic resonance. Results: Our study showed that DHI, PM, and SM could improve cardiac function by correcting the dilated cardiac structure, alleviating inflammation by downregulating complement C2 expression, reducing reactive oxygen species (ROS) production by upregulating cyclooxygenase expression, and restoring normal energy supply by inhibiting fatty acid metabolism and stimulating glycometabolism. In addition, DHI and SM could attenuate the calcium overload and trigger an inflammatory response and oxidative stress by downregulating Ca2+/calmodulin-dependent protein kinase II expression. Conclusions: This study suggests that DHI and its components exerts resistance against MI/RI by ameliorating cardiac dysfunction, energy metabolism, and oxidative stress.