Effects of overexpression of human vascular endothelial growth factor 165 and human tissue inhibitor of metalloproteinase 1 on rats with myocardial infarction / 中华急诊医学杂志

ABSTRACT

Objective:To investigate the effects of recombinant adenovirus with human vascular endothelial growth factor 165 (Ad-hVEGF 165) and recombinant adenovirus with human tissue inhibitor of metalloproteinase 1 (Ad-hTIMP-1) on rats with myocardial infarction (MI) and its mechanism. Methods:A total of 30 healthy 8-week-old male Wistar rats were randomly divided into 5 groups: sham-operated group (sham), virus control group (Ad-Track), Ad-hVEGF 165 group, Ad-hTIMP-1 group and Ad-hVEGF 165+Ad-hTIMP-1 group (hVEGF 165+hTIMP-1) ( n=6 per group). Except the sham group, all rats were ligated the left anterior descending coronary artery to induce MI model with ST-segment elevation and Q waves or T-wave inversion on electrocardiogram and local myocardial whitening. The corresponding recombinant adenovirus comprising 100 μL (1×10 10 VP/100 μL) combined with NaCl solution was injected into the myocardial infarction area at four points respectively. The sham group received no treatment. After 4 weeks, all rats were sacrificed after echocardiography was completed and heart tissues were collected. The expression of hVEGF 165 and hTIMP-1 were detected by immunohistochemistry. The mRNA expression of apoptosis-related factors were detected by real-time PCR. The protein expression of apoptosis-related factors were detected by immunohistochemistry. Differences between groups were determined by One-way analysis of variance. Multiple comparisons between groups were performed using the least significant difference t-test. Results:(1) Both heart rate (HR) (480.83±24.09) beats/min, left ventricular end-diastolic dimension (LVEDD) (6.88±0.44) mm and left ventricular end-systolic dimension (LVESD) (4.85±0.42) mm were increased in the Ad-Track group than those in the sham group (433.16±17.86) beats/min, (6.20±0.45) mm, (4.06±0.70) mm (all P<0.05), and left ventricular ejection fraction (LVEF) (62.70±3.17) % and left ventricular fractional shortening (LVFS) (29.52±1.88) % were significantly decreased in the Ad-Track group than those in the sham group (72.78±5.44)%, (29.52±1.88) % (both P<0.01). Compared with the Ad-Track group, LVEF (71.50±6.23) % and LVFS (36.17±5.27) % in the hVEGF 165-hTIMP-1 group were significantly increased (both P<0.01), and LVEDD (6.22±0.39) mm and LVESD (4.13±0.23) mm were decreased (both P<0.05). LVEF and LVFS in the hVEGF 165-hTIMP-1 group were increased significantly than those in the Ad-hVEGF 165 group (64.65±4.00) %, (30.95±2.57) % (both P<0.05). The mRNA expression of BCL2-associated X protein (Bax), cysteine aspartate specific proteinase 3 (Caspase-3) and BCL-xL/BCL-2-associated death promoter (Bad) in the hVEGF 165-hTIMP-1 group were decreased than those in the Ad-Track group ( P<0.01 or P<0.05), and B-cell lymphoma/leukemia-2 (Bcl-2) in the hVEGF 165-hTIMP-1 group were increased than those in the Ad-Track group ( P<0.01). The mRNA expression levels of Bax and Caspase-3 in the hVEGF 165-hTIMP-1 group were decreased than those in the Ad-hVEGF 165 group (both P<0.05). There was no statistically difference in the mRNA expression of Bax, Caspase-3, Bad, and Bcl-2 between the hVEGF 165-hTIMP-1 group and the sham group (all P>0.05). The protein expression of Bax and Caspase-3 in the hVEGF 165-hTIMP-1 group were significantly decreased than those in the Ad-hVEGF 165 group, the Ad-hTIMP-1 group and the Ad-Track group (all P<0.01), and the protein expression of Bcl-2 in the hVEGF 165-hTIMP-1 group was increased than those in the Ad-hVEGF 165 group, the Ad-hTIMP-1 group and the Ad-Track group (all P<0.05). There were no statistically differences in the protein expression of Bax, Caspase-3 and Bcl-2 between the hVEGF 165-hTIMP-1 group and the sham group (all P>0.05). Conclusions:Ad-hVEGF 165 and Ad-hTIMP-1 can improve cardiac contractile function of MI rats and the beneficial effects are largely attributable to inhibiting myocyte apoptosis. The combination of hVEGF 165 and hTIMP-1 may have a synergistic effect on MI.