Objective: To study the effect of berberine (BR) on ventricular remodeling in experimental rats with myocardial infarction (MI) and its mechanisms.
Methods: The MI model of experimental rats was established by ligation of the left anterior descending coronary artery and the MI animals were randomly divided into 3 groups: MI+BR group, in which the rats received BR 20 mg/kg.d, Sham group and MI group, the rats in those 2 groups received the same volume of normal saline. All animals were treated for 8 weeks. The cardiac function and structure were assessed by echocardiography, cardiac interstitial collagen deposition was evaluated by Masson stain, the myocardial cell apoptosis was detected by Tunel method, and the activation of nuclear factor (NF-κB) was also examined.
Results: For echocardiography, MI group had enlarged left ventricular end diastolic diameter (7.28 ± 0.29) mm than Sham group (6.86 ± 0.36) mm,P<0.05, but it decreased in MI+BR group (6.89 ± 0.99) mm,P>0.05. MI group had increased left ventricular end systolic diameter (5.88 ± 0.33) mm than Sham group (4.61 ± 0.31) mm, but it decreased in MI+BR group (4.68 ± 1.17) mm, allP< 0.01. MI group showed increased left ventricular posterior wall compensatory hypertrophy (1.81 ± 0.85) mm than Sham group (1.67 ± 0.16 mm),P<0.05, while in MI+BR group, it was deereased to (1.65 ± 0.14) mm. MI group presented decreased LVEF (45.77 ± 3.17) % than Sham group (67.28 ± 4.15) %, but it increased in MI+BR group (64.64 ± 5.82) %, allP<0.01. For Masson stain, cardiac interstitial collagen deposition in MI group (11.39 ± 0.45) % was higher than Sham group (2.65 ± 0.45) %, but less in MI+BR group (7.00 ± 0.87) %, allP<0.01. For Tunel examination, the myocardial cell apoptosis index was increased in MI group (21.31 ± 2.34) than Sham group (0.99 ± 0.38), but decreased in MI+BR group (14.15 ± 1.62), allP<0.01. For NF-κB activation study, the nuclear protein p65 content was higher in MI group (0.14 ± 0.02) ng/ml than Sham group (0.06 ± 0.01) ng/ml, but lower in MI+BR group (0.10 ± 0.02) ng/ml, allP<0.01.
Conclusion: Application of BR may improve the ventricular remodeling and cardiac function in experimental MI rats, it might be because of BR partially inhibit NF-κB activation, reduce collagen deposition and help anti-apoptosis in myocardial cells.