Granulocyte Colony-Stimulating Factor Reduces Cardiomyocyte Apoptosis and Improves Cardiac Function in Adriamycin-Induced Cardiomyopathy in Rats

Abstract
Background: Cardiomyocyte apoptosis reportedly participates in the occurrence and progression of dilated cardiomyopathy (DCM). Recent studies have shown that granulocyte colony-stimulating factor (G-CSF) enhances bone marrow cells migration to the damaged heart in the DCM model and improves the ultrastructure of the cardiomyocyte in adriamycin (ADR) induced DCM. However, its influence on cardiac pump function and cardiomyocyte apoptosis has not been studied. Methods and materials: Wistar Rats were randomly grouped into control, ADR, ADR+PBS, ADR+G-CSF group (n = 10). ADR (2.5 mg/kg, 6 times for 2 weeks) was administered intraperitoneally in all rats except the control group. After 2 weeks, the rats in ADR+G-CSF group were injected with G-CSF (50 microg/kg/day for 8 days) subcutaneously. Cardiac function was evaluated by echocardiogram and cardiac catheterization after 4 weeks. Cardiomyocytes apoptosis and apoptosis-related protein Fas were detected by in situ terminal deoxynucleotidyl transferase assay (TUNEL method) and Western blot, respectively. Results: The ADR and ADR+PBS groups showed significant deteriorations of left ventricular functions and high cardiomyocyte apoptosis index, as well as high Fas expressions. Meanwhile, the ADR+G-CSF group showed significant improvement in LV function, inhibition of cardiomyocyte apoptosis compared with the ADR and ADR+Phosphate-Buffered Saline PBS group. The Fas protein expression was remarkably attenuated as well. Conclusion: Our results suggest that administration of G-CSF inhibited cardiomyocyte apoptosis and Fas protein expression and contributes to improving cardiac pump function in vivo in ADR induced DCM rat model.