Role of Macrophage Activation and Polarization in Myocardial Fibrosis and Intervention of Traditional Chinese Medicine / 中国实验方剂学杂志

ABSTRACT

Myocardial fibrosis （MF） is a common pathological manifestation of various heart diseases. Due to the non-renewable nature of myocardial cells， the occurrence of MF represents irreversible damage to the myocardium. Previous studies have suggested that fibroblast-mediated collagen deposition is the main mechanism of MF. Recent studies have found that there is an immune regulation mechanism in the heart itself， and macrophage activation/polarization plays an important role in MF. With the deepening of traditional Chinese medicine research， scholars have found that traditional Chinese medicine can interfere with MF by regulating the renin-angiotensin-aldosterone system （RAAS） system and the inflammatory process， repairing the extracellular matrix， managing oxidative stress， and maintaining the balance of autophagy. This process is closely related to the activation and M1/M2 polarization of macrophages. Throughout the MF process， macrophage activation is beneficial， but excessive activation will be harmful. In the early stage of MF， appropriate M1 macrophage polarization is conducive to activating immunity and removing harmful substances. In the middle and late stages of MF， appropriate M2 macrophage polarization is conducive to remodeling the damaged myocardium. If macrophage activation is excessive/insufficient， or the balance of M1/M2 macrophage polarization is broken， the effect changes from improvement to destruction. Traditional Chinese medicines that regulate the activation/polarization of macrophages have the effects of replenishing Qi and nourishing Yin， as well as regulating Qi and activating blood， but there are also some heat-clearing， dampness-drying， and detoxification products. Therefore， the occurrence of MF may be caused by Qi and Yin deficiency， damp heat accumulation， and Qi stagnation and blood stasis. By summarizing the biological processes involved in macrophage activation/polarization in MF， this paper expounded on the research progress of traditional Chinese medicine in regulating macrophage activation and M1/M2 polarization from different angles to improve MF， so as to provide a reference for the treatment of MF with traditional Chinese medicine.