Oxidative remodeling in pressure overload induced chronic heart failure

• Published in: European journal of heart failure 2007-05, Vol.9 (5), p.450-457
• Main Authors: Henderson, Brooke C., Tyagi, Neetu, Ovechkin, Alexander, Kartha, Ganesh K., Moshal, Karni S., Tyagi, Suresh C.
• Format: Article
• Language: English
• Subjects: Analysis of Variance; Animals; Aortic Valve Stenosis - complications; Aortic Valve Stenosis - metabolism; Aortic Valve Stenosis - physiopathology; Blood Pressure; Blotting, Western; Chronic Disease; collagen; Collagen - metabolism; Disease Models, Animal; Echocardiography; Elastin - metabolism; Electrocardiography; eNOS; Enzyme Activation; Heart Failure - diagnostic imaging; Heart Failure - etiology; Heart Failure - metabolism; Heart Failure - physiopathology; Hypertrophy, Left Ventricular - metabolism; Hypertrophy, Left Ventricular - physiopathology; iNOS; Male; Matrix Metalloproteinase 2 - metabolism; Matrix Metalloproteinase 9 - metabolism; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; MMP; Nitric Oxide Synthase Type II - metabolism; Nitric Oxide Synthase Type III - metabolism; Oxidative Stress; Research Design; Reverse Transcriptase Polymerase Chain Reaction; SOD; Stroke Volume; thioredoxin; Ventricular Dysfunction, Left - metabolism; Ventricular Dysfunction, Left - physiopathology
• ISSN: 1388-9842; 1879-0844
• DOI: 10.1016/j.ejheart.2006.12.008

Despite extensive strides in understanding pressure overload induced heart failure, there is very little known about oxidative stress induced matrix metalloproteinase (MMP) activation, collagen degradation and remodeling in pressure overload heart failure. We hypothesize that pressure overload leads to redox imbalance causing increased expression/activity of MMP-2/9 producing collagen degradation and heart failure. To test this hypothesis, we created pressure overload heart failure by abdominal aortic stenosis (AS) in wild-type C57BL/6J and collagen mutant (Col1a1 with 129 s background) mice. At 4 weeks, post surgery, functional parameters were measured. Left ventricle (LV) tissue sections were analyzed by histology, Western Blot and PCR. The results suggest an increase in iNOS with a decrease in eNOS, an increase in nitrated protein modification and depletion of antioxidants thioredoxin and SOD in pressure overload. MMP-2/9 expression/activity and collagen degradation were increased in the AS animals. To determine whether a mutation in the collagen gene at the site of MMP cleavage mitigates cardiac hypertrophy, we used Col1a1 mice. In these mice, the AS induced LV hypertrophy (LVH) was ameliorated. In conclusion, our results suggest that AS leads to increased oxidative stress, expression/activity of MMP-2/9 and a decrease in antioxidant expression producing collagen degradation and heart failure.