Proteomics analysis identified peroxiredoxin 2 involved in early-phase left ventricular impairment in hamsters with cardiomyopathy

<div><p>Given the hypothesis that inflammation plays a critical role in the progression of cardiovascular diseases, the aim of the present study was to identify new diagnostic and prognostic biomarkers of myocardial proteins involved in early-phase cardiac impairment, using proteomics analysis. Using the two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) combined with MALDI-TOF/TOF tandem mass spectrometry, we compared differences in the expression of proteins in the whole left ventricles between control hamsters, dilated cardiomyopathic hamsters (TO-2), and hypertrophy cardiomyopathic hamsters (Bio14.6) at 6 weeks of age (n = 6, each group). Proteomic analysis identified 10 protein spots with significant alterations, with 7 up-regulated and 3 down-regulated proteins in the left ventricles of both TO-2 and Bio 14.6 hamsters, compared with control hamsters. Of the total alterations, peroxiredoxin 2 (PRDX2) showed significant upregulation in the left ventricles of TO-2 and Bio 14.6 hamsters. Our data suggest that PRDX2, a redox regulating molecule, is involved in early-phase left ventricular impairment in hamsters with cardiomyopathy.</p></div

Amounts of PRDX in 6-week-old F1B, TO-2, and Bio 14.6 hamsters.

<p>(A) Representative immunoblots of each protein. (B) The amount of each protein quantitated relative to the amount of β-actin and expressed relative to the value of F1B control hamsters. Data are mean±SEM of six animals per group. *<i>P</i><0.05, versus F1B control hamsters. (C) Light micrographs of myocytes in hematoxylin-eosin stained sections and (D) immunohistochemical staining for PRDX in the left ventricles of representative F1B, TO-2, and Bio 14.6 hamsters. Scale bars, 100 μm.</p

Gene Ontology (GO) annotation of identified proteins.

<p>The graphs show the percentages of corresponding GO terms to the total number of annotated proteins. The identified up-regulated and down-regulated proteins were mapped to GO at (A) biological process and (B) molecular function.</p

Physiological data of 6-week-old F1B, TO-2, and Bio 14.6 hamsters.

<p>(A) Body weight, (B) LV weight/body weight, (C) thickness of the intra-ventricular septum, (D) LV end-diastolic dimension, (E) LV end-systolic dimension, and (F) fraction shortening. Data are mean±SEM of six animals per group. *<i>P</i><0.05 versus F1B control hamsters.</p

Representative 2D-DIGE image and images of spots with significant alterations in LV lysates.

<p>(A) Proteins (40 μg each) were labeled with Cy3 and Cy5 dyes, mixed and subjected to 2D-DIGE analysis. Cy3- and Cy5- images are illustrated using red and green pseudocolors, respectively. Images were analyzed using DeCyder software. IPG strips (pI 3–11) were used for IEF, and 12.5% SDS-PAGE for the second dimension. (B) The 2-DE images of 4 spots showed significant alterations in the left ventricles of both TO-2 and Bio 14.6 hamsters, compared with F1B control hamsters.</p

Gene expression of ANP, BNP, collagen I, and collagen III in 6-week-old F1B, TO-2, and Bio 14.6 hamsters.

<p>The mRNA levels of (A) ANP, (B) BNP, (C) collagen I, and (D) collagen III in the heart tissues were determined by quantitative RT-PCR analysis. Data are normalized by the abundance of GAPD mRNA. Quantitative data are expressed relative to the values for F1B hamsters. Data are mean s±SEM of six animals per group. *<i>P</i><0.05 versus F1B control hamsters.</p

List of proteins with significant differences in their levels in heart tissues of TO-2, Bio 14.6, and F1B hamsters.

<p>List of proteins with significant differences in their levels in heart tissues of TO-2, Bio 14.6, and F1B hamsters.</p