OBJECTIVESome research has shown that resveratrol can ameliorate myocardial injury and improve cardiac function in mice with acute viral myocarditis (VMC), and can inhibit cardiac fibroblast proliferation and myofibroblast differentiation in vitro. This study was designed to investigate whether resveratrol has similar effects in the mouse model of chronic VMC.

METHODSOne hundred mice were inoculated with 0.3 mL of Coxsackievirus B3 1*106 TCID50. Thirty days later, the survivors (n=62) were used as a model of chronic VMC, and were randomly assigned to 4 groups: untreated VMC, and low- (10 mg/kg), middle- (100 mg/kg) and high-dose (1 000 mg/kg) resveratrol-treated VMC (once daily, for 30 days). Ten mice which received neither Coxsackievirus B3 nor resveratrol treatment served as the control group. After 30 days of resveratrol treatment, the mice were sacrificed. Serum concentrations of collagenous pre-peptides (PINP, PICP and PIIINP) were assessed using ELISA. Hematoxylin-eosin staining, picrosirius red staining and circularly polarized light were used to examine the histochemistry of myocardial collagen.

RESULTSThe myocardial collagen volume fraction in the high-dose (0.74+/-0.19) and the middle-dose (1.07+/-0.12) resveratrol-treated VMC groups was significantly lower than that in the untreated VMC (2.33+/-0.18) and the low-dose resveratrol-treated VMC (2.17+/-0.19) groups (P<0.05). Compared with the untreated VMC group, serum concentrations of PICP and PIIINP in the high-dose and the middle-dose resveratrol-treated VMC groups were significantly reduced (P<0.05), while PINP concentrations increased significantly (P<0.05).

CONCLUSIONSResveratrol can inhibit hyperplasia of myocardial collagen in the mouse model of chronic VMC, acting as an effective anti-fibrotic agent in the myocardium.