Costunolide Reduces Doxorubicin-Induced Cardiomyocyte Injury by Inhibiting Mitochondrial Apoptosis and Autophagy

This study was to investigate the protective effect and mechanism of Cos (costunolide) on DOX (doxorubicin)-induced cardiomyocyte injury. In cell experiments, H9C2 cardiomyocytes were divided into normal group, model group, low-dose group, medium-dose group and high-dose group, and DOX was used to establish in jury model. EDU was used to detect cell proliferation activity; flow cytometry was employed to precisely measure the apoptosis rate of the cells, while immunofluorescence staining was utilized to accurately detect the expression of LC3 protein, providing valuable insights into the cellular physiological state. In the animal experiment, a total of SD rats were randomly allocated into five distinct groups: Ctrl group, Model group, L-Cos group, M-Cos group, and H-Cos group, with ten rats in each group. The cardiac function parameters of these rats were measured. Addi tionally, HE staining and Masson’s trichrome staining were employed to examine the pathological alterations in the myocardial tissue. Western blot was meticulously employed to detect and analyze the expression levels of proteins that were closely associated with apoptosis and autophagy processes, aiming to uncover the underlying molecular mechanisms in the studied biological system. The number of autophagosomes in mitochondria of cardiomyocytes was observed under electron microscope. (1) In the cellular experiment, the proportion of EDU-positive H9C2 cells in the model group was notably decreased compared with that in the normal group (P<0.05). The rates of apopto sis and the fluorescence intensity of LC3 experienced a significant elevation (P<0.05). Compared with the model group, the EDU positive rate of H9C2 cells in the low-dose group, middle-dose group and high-dose group was sig nificantly increased (P<0.05). The apoptosis rate and LC3 fluorescence intensity were significantly decreased in a dose-dependent manner (P<0.05). (2) In animal experiments, compared with the Ctrl group, LVESD, LVEDD, p53, Bax, and Bnip3 protein expression, LC3-II/LC3-I ratio, and the count of mitochondrial autophagosomes within car diomyocytes were notably higher in the Model group (P<0.05). LVFS and LVEF, along with the protein expression levels of Bcl-2 and P62, were significantly reduced (P<0.05). Compared with the Model group, LVESD, LVEDD, p53, Bax, and Bnip3 protein expression, LC3-II/LC3-I ratio, and the number of mitochondrial autophagosomes in cardiomyocytes were significantly decreased in the L-Cos group, M-Cos group, and H-Cos group (P<0.05). LVFS and LVEF, Bcl-2 and P62 protein expression levels were significantly increased in a dose-dependent man ner (P<0.05). Cos can inhibit the process of excessive mitophagy in cardiomyocytes, block the apoptotic signaling pathway, enhance the metabolic activity of cells and reduce the degree of myocardial fibrosis, and ultimately im prove cardiac function and effectively resist DOX-induced myocardial toxic injury.

CSTR: 32200.14.cjcb.2025.11.0013