Objective: To investigate the effect of endostatin gene transfer mediated by electric pulses into skeletal muscles of mice upon the develpment of atherosclerotic plaques.
Methods: Eukaryotic expression plasmid of mouse endostatin was injected into the muscles of 2 groups of ApoE-deficient mice, group A at the age of 24 weeks, and group B at the age of 36 weeks (named therapy group as a whole). Gene transfer was mediated by electric pulses for ten times. Empty plasmid was used to mice at the same ages as controls. Twenty weeks later, blood-lipid was tested, and the aortas of the experimental animals were taken out to examine the areas of atherosclerotic plaques and count the endothelial cells and microvessels in the plaques.
Results: In the 24-week-aged group, the stenosis rate of aorta 16% +/- 4% before the experiment. Twenty weeks later, the stenosis rate was 56% +/- 14% among the control mice, and was 34% +/- 8% among the treated ones with an improvement rate of 54%. In the 36-week-aged group, the stenosis rate of aorta was 30% +/- 6% before the experiment. Twenty weeks after the begining of experiment, the stenosis rate was 64% +/- 12% among the control mice, and was 49% +/- 10% among the treated ones with an improvement rate of 44%. Twenty weeks after the begining of experiment, the endothelial cell count and microvessel appearance rate were less among the therapy group than among the controls. There was no significant difference in blood-lipid between the therapy group and the control group.
Conclusion: Endostatin gene transfer into skeletal muscle effectively inhibits the development of atherosclerotic plaques.