Abstract: Objective: To test the hypothesis that IL-10 might be useful for promoting left ventricular remodeling and cardiac function by modulating extracellular matrix after acute myocardial infarction. Methods: Male adult rats were divided into three groups in random: control group (n=6), MI/AAV2 group (n=16) and MI/AAV2-IL-10 group (n=16). Establishing animal modol of experimental myocardial infarction and equal dose of recombinant adeno-associated virus type 2 (AAV)/IL-10 (AAV2-rhIL-10) and AAV2 were injected around the ischemic zone. Echocardiography parameters, hemodynamic parameters, left ventricular mass index (LVMI), collagen volume fraction (CVF), perivascular circumferential area (PVCA), collagen type Ⅰ&Ⅲ volume fraction and mRNA levels of collagen type Ⅰ&Ⅲ, matrix metalloproteinases-2 (MMP-2) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were compared between the three groups. Results: Improved cardiac function was observed in MI/AAV2-IL-10 group both by echocardiography and hemodynamic examination. 4 weeks after myocardial infarction, thickness of different parts of LV was same in MI/AAV2-IL-10 group and MI/AAV2 group. Nevertheless CVF, PVCA, and collagen type I volume fraction was significantly descending in remote zone of MI/AAV2-IL-10 group compared with that of MI/AAV2 group, P＜0.01. The mRNA expression of collagen type I and MMP-2 was lower in MI/AAV2-IL-10 group than that in MI/AAV2 group, P＜0.05 and P＜0.01 in turn. Conclusions: Recombinant IL-10 expression mediated by AAV2-rhIL-10 transfection of rats' myocardium contributes to promoting LV remodeling and cardiac function after acute myocardial infarction. The promotion was partially achieved by inhibition myocardium collagen deposition.

Key words: Interleukin-10, Left ventricular remodeling, matrix metalloproteinase