Effects of granulocyte-colony stimulating factor on cardiac remodeling after myocardial infarction.

Background: Recent studies suggest that granulocyte colony-stimulating factor (G-CSF) may be beneficial in the treatment of myocardial infarction (MI). However, the effects of G-CSF on MI are still controversial and the molecular mechanism of G-CSF treatment for repair of the infarcted heart is not fully understood.

Methods: Mice were divided into three groups: Control, MI and MI treated with G-CSF. Four weeks after MI, we examined cardiac function by Doppler echocardiography and measured non-infarcted myocardial mRNA expression by northern blot analysis.

Results: Cardiac function decreased significantly in the MI groups compared with the sham-operated groups. Additionally, the ratios of E wave to A wave peak velocity (E/A) in the MI groups were higher than in the control group. E/A in G-CSF MI mice was significantly lower than in control MI mice (p<0.01). Matrix metalloproteinase-2 (MMP-2) mRNA expression was significantly increased in the MI groups compared with the control group (p<0.01). Furthermore, mRNA expression in the G-CSF MI group was significantly higher than in the Control MI group (p<0.05).

Conclusions: G-CSF can prevent the LV remodeling process after MI that accompanies progressive cardiac dysfunction. One of the mechanisms of G-CSF treatment for cardiac remodeling after MI may be overexpression of MMP-2 in non-infarcted myocardium.