Inhibition of NF-κB improves left ventricular remodeling and cardiac dysfunction after myocardial infarction

Inhibition of NF-kappa B improves left ventricular remodeling and cardiac dysfunction after myocardial infarction. Am J Physiol Heart Circ Physiol 292: H530-H538, 2007. First published August 18, 2006; doi:10.1152/ajpheart. 00549.2006.-Several studies have demonstrated that NF-kappa B is substantially involved in the progression of cardiac remodeling; however, it remains uncertain whether the continuous inhibition of NF-kappa B is effective for the prevention of myocardial remodeling. Myocardial infarction (MI) was produced by ligation of the left anterior coronary artery of rats. IMD-0354 ( 10 mg/kg per day), a novel phosphorylation inhibitor of I kappa B that acts via inhibition of IKK-beta,was injected intraperitoneally starting 24 h after induction of MI for 28 days. After 28 days, the IMD-0354-treated group showed significantly improved survival rate compared with that of the vehicle-treated group (P < 0.05). Although infarct size was similar in both groups, improved left ventricular (LV) remodeling and diastolic dysfunction, as indicated by smaller LV cavity (LV end-diastolic area: vehicle, 74.13 +/- 3.57 mm(2); IMD-0354, 55.00 +/- 3.73 mm(2); P < 0.05), smaller peak velocity of early-to-late filling wave (E/A) ratio (vehicle, 3.87 +/- 0.26; IMD-0354, 2.61 +/- 0.24; P < 0.05), and lower plasma brain natriuretic peptide level (vehicle, 167.63 +/- 14.87 pg/ml; IMD- 0354, 110.75 +/- 6.41 pg/ml; P < 0.05), were observed in the IMD-0354-treated group. Moreover, fibrosis, accumulation of macrophages, and expression of several factors (transforming growth factor-beta 1, monocyte chemoattractant protein-1, matrix metalloproteinase-9 and -2) in the noninfarcted myocardium was remarkably inhibited by IMD-0354. In conclusion, inhibition of NF-kappa B activation may reduce the proinflammatory reactions and modulate the extracellular matrix and provide an effective approach to prevent adverse cardiac remodeling after MI.