[Cardioprotective effect and mechanism of post-infarction ventricular remodeling after self-assembling peptide and thermosensitive hydrogel implantation in rat myocardial infarction model].
OBJECTIVE
To compare the cardioprotective effect of self-assembling peptide (RAD16-II) and thermosensitive hydrogel DPHP (Dex-PCL-HEMA/PNIPAAm) and investigate the optimal property of hydrogel for the treatment of myocardial infarction (MI).


METHODS
MI model was induced by left anterior descending (LAD) coronary artery ligation in SD rats. The animals were randomized into three groups to receive RAD16-II hydrogel (n = 15), DPHP hydrogel (n = 15) or PBS (phosphate buffered saline; control group n = 15); sham-operated rats (n = 10), a suture was tied loosely around left coronary artery without ligating it. At Day 20 post-MI, left ventricle function was evaluated by echocardiography and cardiac catheter. Masson's trichrome was used for histological examination; anti-alpha-smooth muscle antigen (alpha-SMA) was applied to label the neovasculature formation in infarct area.


RESULTS
The rats receiving DPHP hydrogel showed a significantly smaller left ventricle end diastolic diameter (LVEDd) and higher levels of left ventricle fraction shortening (LVFS) and left ventricle end systolic pressure (LVESP) than the rats in RAD16-II group [LVEDd (7.9 +/- 0.9) mm vs (8.9 +/- 0.8) mm]; [LVFS (25.4 +/- 5.1)% vs (21.9 +/- 2.9)%; LVESP (114.0 +/- 7.6) mm Hg vs (99.1 +/- 9.6) mm Hg; P < 0.05]. Histological examination showed uncompleted degraded hydrogel in infarct area of DPHP group but not in RAD16-II group. The animals receiving DPHP hydrogel demonstrated significantly a smaller infarct size, a higher infarct wall thickness and a lower vessel density in infarct than the animals receiving RAD16-II hydrogel (P < 0.05).


CONCLUSIONS
DPHP hydrogel implantation further inhibits the post-MI ventricle remodeling than RAD16-II hydrogel implantation. The mechanism is not correlated with the vascular density in infarct area.
Wang
Tao
T
Department of Cardiology, Renmin Hospital of Wuhan University, Cardiovascular Institute of Wuhan University, Wuhan 430060, China.
Lin
Tao
T
Ren
Shan
S
Yuan
Ming-Jie
MJ
Li
Xiao-Yan
XY
Jiang
Xue-Jun
XJ
D000818:Animals; D020100:Hydrogels / Q000627:therapeutic use*; D008297:Male; D009203:Myocardial Infarction / Q000503:physiopathology* / Q000628:therapy*; D009842:Oligopeptides / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020257:Ventricular Remodeling
D020100:Hydrogels; D009842:Oligopeptides; C098328:RAD16 peptide