Reversal of Wolff-Parkinson-White Syndrome induced dilated cardiomyopathy via resynchronization and subsequent accessory pathway ablation

Recurrent or incessant tachycardia is frequently found in symptomatic Wolff-Parkinson-White （WPW） syndrome, leading to ventricular dysfunction, dilated cardiomyopathy （DCM） and heart failure in infants and children.[1] Recently, Winter, et al.[2] report that WPW syndrome could provoke many kinds of cardiac dysfunction, leading to remodeling and progressive ventricular dilatation through pre-excita- tion-related dyssynchrony, even without arrhythmia.

Effects of rosuvastatin on the production and activation of matrix metalloproteinase-2 and migration of cultured rat vascular smooth muscle cells induced by homocysteine

Objective： To test the influence of homocysteine on the production and activation of matrix metalloproteinase-2 （MMP-2） and tissue inhibitors of matrix metalloproteinase-2 （TIMP-2） and on cell migration of cultured rat vascular smooth muscle cells （VSMCs）. Also, to explore whether rosuvastatin can alter the abnormal secretion and activation of MMP-2 and TIMP-2 and migration of VSMCs induced by homocysteine. Methods： Rat VSMCs were incubated with different concentrations of homocysteine （50-5000 μmol/L）. Western blotting and gelatin zymography were used to investigate the expressions and activities of MMP-2 and TIMP-2 in VSMCs in culture medium when induced with homocysteine for 24, 48, and 72 h. Transwell chambers were employed to test the migratory ability of VSMCs when incubated with homocysteine for 48 h. Different concentrations of rosuvastatin （10^-9-10^-5 mol/L） were added when VSMCs were induced with 1 000 pmol/L homocysteine. The expressions and activities of MMP-2 and TIMP-2 were examined after incubating for 24, 48, and 72 h, and the migration of VSMCs was also examined after incubating for 48 h. Results： Homocysteine （50-1000 μmol/L） increased the production and activation of MMP-2 and expression of TIMP-2 in a dose-dependent manner. However, when incubated with 5000 pmol/L homocysteine, the expression of MMP-2 was up-regulated, but its activity was down-regulated. Increased homocysteine-induced production and ac- tivation of MMP-2 were reduced by rosuvastatin in a dose-dependent manner whereas secretion of TIMP-2 was not significantly altered by rosuvastatin. Homocysteine （50-5000 μmol/L） stimulated the migration of VSMCs in a dose-dependent manner, but this effect was eliminated by rosuvastatin. Conclusions： Homocysteine （50-1000 μmol/L） significantly increased the production and activation of MMP-2, the expression of TIMP-2, and the migration of VSMCs in a dose-dependent manner. Additional extracellular rosuvastatin can decrease the excessive expression and acti- vation of MMP-2 and abnormal migration of VSMCs induced by homocysteine.