[Differential expression of miRNAs in myocardial tissues of rats with lipopolysaccharide- induced endotoxemia].
OBJECTIVE
To analyze the differential miRNA expression profile in the myocardium of rats with lipopolysaccharide (LPS)-induced endotoxemia and explore the role of miRNA in endotoxin-induced myocardial injury.


METHODS
Twenty male SD rats received intraperitoneal injection of 10 mg/kg LPS (n=10) or an equivalent amount of saline solution (n=10). At 24 h after LPS injection, the rats were sacrificed to detect myocardial expressions of TLR4, TNF-α and IL-1β using real-time PCR and for observing myocardial ultrastructures under transmission electron microscopy. The differentially expressed miRNA in the myocardium were detected using a miRNA array, and the common differentially expressed miRNAs were selected for verifying their actual expressions using real-time PCR.


RESULTS
TLR4, TNF-α and IL-1β were over-activated in the myocardium of LPS-treated rats, in which mitochondria swelling, structural damaged and cytoplasmic vacuoles were observed. In LPS-challenged rats, miR-194-3p, miR-344a-3p, miR-465-3p, miR-501-5p, miR-3596c, miR-185-3p, and miR-877 were found up-regulated significantly, whereas miR-208b-3p, miR-547-3p, miR-141-3p, miR-28-5p, and miR-3585-5p down-regulated in the myocardium.


CONCLUSIONS
Significant differential expression of the miRNAs occurs in the myocardium of LPS-treated rats, suggesting their involvement in endotoxin-induced myocardial injury.
Pharmaceutical College of Kunming Medical University, Kunming 650500, China.E-mail: dt101180@sina.com.
Tao
T
Ding
Yang
Y
Li
Ruizhu
R
Tang
Xuan
X
Zhang
Yu
Y
Yun
Jian
J
Li
Dianhua
D
Wang
D000818:Animals; D019446:Endotoxemia / Q000378:metabolism*; D007274:Injections, Intraperitoneal; D053583:Interleukin-1beta / Q000378:metabolism; D008070:Lipopolysaccharides; D008297:Male; D035683:MicroRNAs / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D051197:Toll-Like Receptor 4 / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D015854:Up-Regulation
D053583:Interleukin-1beta; D008070:Lipopolysaccharides; D035683:MicroRNAs; C495347:Tlr4 protein, rat; D051197:Toll-Like Receptor 4; D014409:Tumor Necrosis Factor-alpha