Proteomic changes in the pressure overloaded right ventricle after 6 weeks in young rats: Correlations with the degree of hypertrophy

Abstract

Right ventricular (RV) hypertrophy is an important problem in congenital heart disease. We determined the alterations in phenotype that occur in the initial phase of RV hypertrophy and their possible correlations with the degree of hypertrophy. Therefore, we performed a differential proteomic profiling study on RV hypertrophy using an animal model of pulmonary artery banding (PAB) in parallel with hemodynamic characterization. The RV homogenates were subfractionated in myofilament and cytoplasmic proteins, which subsequently were separated by two-dimensional gel electrophoresis (2-DE), excised, and analyzed by mass spectrometry (MS). The cytoplasmic fraction showed expression changes in metabolic proteins, indicative of a shift from fatty acid to glucose as a substrate for energy supply. Up-regulation of three HSP-27s (1.9-, 1.7-, and 3.5-fold) indicated an altered stress response in RV hypertrophy. Detailed analysis by immunoblotting and MS showed that two of these HSP-27s were at least phosphorylated on Ser15. The myofilament fraction showed up-regulation of desmin and alpha-B-crystallin (1.4-and 1.3-fold, respectively). This alteration in desmin was confirmed by 1-DE immunoblots. Certain differentially expressed proteins, such as HSP-27, showed a significant correlation with the RV weight to the body weight ratio in the PAB rats, suggesting an association with the degree of hypertrophy.

Pressure-overload hypertrophy of the developing heart reveals activation of divergent gene and protein pathways in the left and right ventricular myocardium

“…Heat shock proteins are ubiquitously expressed, and to protect cardiomyocytes from injury, heat shock proteins within the cell increase in response to externally applied stressors. In contrast with our (8).…”

Right and left ventricular function after chronic pulmonary artery banding in rats assessed with biventricular pressure-volume loops

“…One of the challenges is to identify the turning point from compensated RV hypertrophy to (irreversible) RV failure. In a previous study, we reported the changes in the myocardial protein expression in response to RV pressure overload (12). We demonstrated alterations in expression of metabolic proteins, compatible with a shift from fatty acid to carbohydrate metabolism.…”

“…A major advantage of the use of these small disease models is that cardiac material can be easily sampled to study critically involved molecular changes over time and the possibility to study effects of transgenesis and gene ablation (2,5,22,23,34). Recently, we performed a proteomic profiling study on RV hypertrophy showing multiple expression and posttranslational changes in metabolic, stress, and myofilament proteins (12). To interpret these molecular findings in terms of possible mechanisms involved in RV remodeling, an accurate assessment of RV function is required, preferably by using load-independent parameters of cardiac contractility (13,24,29,30).…”

Prorenin Induces Intracellular Signaling in Cardiomyocytes Independently of Angiotensin II

“…Gels were scanned and aligned in Syquest (Biorad) to quantify differential expression of proteins. 11 Selected protein spots were excised, trypsin digested, and subjected to matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry for protein identification. Peptide mass fingerprints were analyzed using the Mascott protein database (www.matrixscience.com) and the Mowse score automatic cutoff.…”