Analysis of ceRNA Network and Identification of Potential Treatment Target and Biomarkers of Endothelial Cell Injury in Sepsis.

Background: Sepsis is a complex clinical syndrome caused by a dysregulated host immune response to infection. This study aimed to identify a competing endogenous RNA (ceRNA) network that can greatly contribute to understanding the pathophysiological process of sepsis and determining sepsis biomarkers. Methods: The GSE100159, GSE65682, GSE167363, and GSE94717 datasets were obtained from the Gene Expression Omnibus (GEO) database. Weighted gene coexpression network analysis was performed to find modules possibly involved in sepsis. A long noncoding RNA-microRNA-messenger RNA (lncRNA-miRNA-mRNA) network was constructed based on the findings. Single-cell analysis was performed. Human umbilical vein endothelial cells were treated with lipopolysaccharide (LPS) to create an in vitro model of sepsis for network verification. Reverse transcription-polymerase chain reaction, fluorescence in situ hybridization, and luciferase reporter genes were used to verify the bioinformatic analysis. Result: By integrating data from three GEO datasets, we successfully constructed a ceRNA network containing 18 lncRNAs, 7 miRNAs, and 94 mRNAs based on the ceRNA hypothesis. The lncRNA ZFAS1 was found to be highly expressed in LPS-stimulated endothelial cells and may thus play a role in endothelial cell injury. Univariate and multivariate Cox analyses showed that only SLC26A6 was an independent predictor of prognosis in sepsis. Overall, our findings indicated that the ZFAS1/hsa-miR-449c-5p/SLC26A6 ceRNA regulatory axis may play a role in the progression of sepsis. Conclusion: The sepsis ceRNA network, especially the ZFAS1/hsa-miR-449c-5p/SLC26A6 regulatory axis, is expected to reveal potential biomarkers and therapeutic targets for sepsis management.

Interleukin-11 protects mouse liver from warm ischemia/reperfusion (WI/Rp) injury.

BACKGROUND: IL-11 is a multifunctional cytokine that belongs to the IL-6 family. Previous studies have demonstrated that IL-11 has underlying anti-inflammatory and anti-apoptotic properties. In this study, we evaluated the potential effects of IL-11 on mouse liver WI/Rp injury. METHODS: For in vivo experiments, mice were randomly divided into four main experimental groups (n=5 each): (1) normal group - anesthesia; (2) sham group- laparotomy; (3) I/R group- liver WI/Rp; and (4) IL-11 pretreatment (500µg/kg, tail vein injection) group- administration of RhIL-11 2h before liver WI/Rp induced in the same manner as in group 3. For in vitro experiments, cells were divided into two groups: (1) H/R group- H/R; and (2) IL-11 pretreatment group- pretreatment with RhIL-11 (2µg/mL for 12h) before the induction of H/R. For both groups, three periods of reoxygenation were examined (2h, 6h, and 12h). RESULTS: In the in vivo experiments, IL-11 protected mouse livers from WI/Rp by reducing liver enzyme levels and cellular degeneration. In the in vitro experiments, IL-11 significantly reduced hepatocyte apoptosis. In both the in vivo and in vitro experiments, IL-11 pre-treatment significantly reduced the expression of TNF-α and IL-1ß. In addition, NF-κB, a target of IL-11, was suppressed in macrophages after IL-11 pre-treatment. CONCLUSIONS: Pre-treatment with IL-11 protects mouse livers from WI/Rp injury by suppressing NF-kB activity.

MicroRNA-497 regulates cell proliferation in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the most common primary cancer of the liver. MicroRNA-497 (miR-497) is known to be downregulated in several types of human cancer; however, the expression, function and underlying mechanisms of miR-497 in HCC remain unclear. Therefore, the present study investigated miR-497 expression in HCC samples and HCC-derived cell lines using reverse transcription-quantitative polymerase chain reaction. The protein expression of one of the predicted common targets of miR-497, insulin-like growth factor-1 receptor (IGF-1R), was assessed using western blot analyses and immunohistochemistry. The role of miR-497 in regulating the proliferation of HCC-derived cells was also investigated in vitro and in vivo. Of 60 paired specimens from HCC patients, miR-497 was downregulated in 42 cancer specimens compared with adjacent non-cancer tissues. Western blotting and immunohistochemical analyses revealed that IGF-1R expression was significantly increased in HCC compared to control tissues. In addition, overexpression of miR-497 was observed to inhibit colony formation and tumor growth in MHCC-97H human HCC cells. Conversely, SMMC-7721 human HCC cells transfected with a miR-497 inhibitor exhibited enhanced colony formation and tumor growth. Finally, IGF-1R protein, phosphoinositide 3-kinase/Akt signaling pathway-associated proteins and cyclin pathway-associated proteins were differentially expressed between miR-497-overexpressing cells and miR-497-silenced cells. These results indicate that miR-497 may be a potentially effective gene therapy target.

The microRNA-146a/b attenuates acute small-for-size liver graft injury in rats.

BACKGROUND & AIMS: A critical role of the Toll-like receptor (TLR)-4 and its downstream mediators in the pathogenesis of small-for-size liver graft injury has been documented. Recently, the microRNA-146 (miR-146) was identified as a potent negative regulator of the TLR4 signalling pathway. In this study, the role of miR-146a and miR-146b in the attenuation of TLR-4 signalling and small-for-size liver graft injury was investigated. METHODS: The expression levels of miR-146a and miR-146b during small-for-size liver graft injury were studied in vivo. In addition, the effects of miR-146a and miR-146b on the expression of IRAK1 and TRAF6 in the rat macrophage cell line NR8383 and rat liver kupffer cells were studied in vitro. The in vivo effect of miR-146a and miR-146b on small-for-size liver graft injury was studied by the tail vein injection of miR-146a mimics and miR-146b mimics. RESULTS: The levels of miR-146a and miR-146b decreased with a small-for-size liver graft. MiR-146a and miR-146b inhibited IRAK1 and TRAF6 expression by binding to the 3'UTR of IRAK1 or TRAF6, respectively, in the rat macrophage cell line NR8383. The administration of miR-146a mimics and miR-146b mimics prevented liver graft injury in small-for-size liver graft injury via the inactivation of IRAK1 and TRAF6 in vivo. CONCLUSIONS: miR-146a and miR-146b prevent liver injury in small-for-size liver graft injury via the inactivation of IRAK1 and TRAF6.