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Abstract:   (215 Views)
Background: The molecular mechanisms of cardiac hypertrophy progression are not well understood. The aim of the current study was to investigate the cardiac transcriptional profile of the key regulatory proteins, sirtuins family (SIRT1-7), in adaptive and mal-adaptive phases of pressure overload-induced hypertrophy.
Methods: Left ventricular hypertrophy was induced in male Wistar rats (170 -210 g) by abdominal aortic banding. The third and sixteenth weeks post-surgery were considered as adaptive and maladaptive phases of hypertrophy (H3w and H16w groups, respectively). Intact animals served as control (n=8 in each group). Blood pressure (BP) was recorded through the carotid artery catheter. Cell area and fibrosis were assessed using haematoxylin/eosin and Masson trichrome staining, respectively. The sirtuins mRNA levels were quantified using Real Time RT–PCR technique.
Results: H3w rats had a higher systolic and diastolic BP, cardiomyocytes size and heart to body weight ratio (HW/BW) compared with control. Although cell size and HW/BW increased in the H16w group, systolic and diastolic BP did not change significantly. In the cardiac tissue of H3w group SIRT1, SIRT3, SIRT6 and SIRT7mRNA levels increased significantly (P<0.05 for SIRT1, SIRT3, and SIRT6 and P<0.01 for SIRT7 vs. control). In H16w group, SIRT1, SIRT3, SIRT5, SIRT6 and SIRT7 mRNA level declined in comparison with H3w group. SIRT2 and SIRT4 mRNA levels did not change significantly among the experimental groups.
Conclusions: Our results reveal that transcriptional profile of sirtuins changes during progression of cardiac hypertrophy. Therefore, it can validate sirtuins as the pharmacological targets for the treatment of pathological hypertrophy.
Types of Manuscript: Original Research | Subject: Cardivascular system