Publication Date:
2015-04-29
Description:
ABSTRACT BACKGROUND This study aimed to investigate the effect of microRNA-30b (miR-30b) in rat myocardial ischemic-reperfusion (I/R) injury model. METHODS We randomly divided Sprague-Dawley (SD) rats (n = 80) into five groups: 1) control group; 2) miR-30b group; 3) sham-operated group; 4) I/R group and 5) I/R + miR-30b group. Real-time quantative polymerase chain reaction, immunohistochemical staining and Western blot analysis were conducted. TUNEL assay was employed for testing cardiomyocyte apoptosis. RESULTS Our results showed that miR-30b levels were down-regulated in I/R group and I/R + miR-30b group compared with sham-operated group (both P 〈 0.05). However, miR-30b level in I/R + miR-30b group was higher than I/R group ( P 〈 0.05). Markedly, the apoptotic rate in I/R group showed highest in I/R group ( P 〈 0.05). Additionally, the results illustrated that protein levels of Bcl-2, Bax and caspase-3 were at higher levels in ischemic regions in I/R group, comparing to sham-operated group (all P 〈 0.05), while Bcl-2/Bax was reduced ( P 〈 0.05). Bcl-2 level and Bcl-2/Bax were obviously increased in I/R + miR-30b group by comparison with I/R group, and expression levels of Bax and caspase-3 were down-regulated (all P 〈 0.05). We also found that in I/R + miR-30b group, KRAS level was apparently lower and p-AKT level was higher by comparing with I/R group (both P 〈 0.05). CONCLUSION Our study indicated that miR-30b overexpression had anti-apoptotic effect on early phase of rat myocardial ischemia injury model through targeting KRAS and activating the Ras/Akt pathway. This article is protected by copyright. All rights reserved
Electronic ISSN:
0091-7419
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
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