The associations of long non-coding RNA taurine upregulated gene 1 and microRNA-223 with general disease severity and mortality risk in sepsis patients

Modes of action and diagnostic value of miRNAs in sepsis

Sepsis is a clinical syndrome defined as a dysregulated host response to infection resulting in life-threatening organ dysfunction. Sepsis is a major public health concern associated with one in five deaths worldwide. Sepsis is characterized by unbalanced inflammation and profound and sustained immunosuppression, increasing patient susceptibility to secondary infections and mortality. microRNAs (miRNAs) play a central role in the control of many biological processes, and deregulation of their expression has been linked to the development of oncological, cardiovascular, neurodegenerative and metabolic diseases. In this review, we discuss the role of miRNAs in sepsis pathophysiology. Overall, miRNAs are seen as promising biomarkers, and it has been proposed to develop miRNA-based therapies for sepsis. Yet, the picture is not so straightforward because of the versatile and dynamic features of miRNAs. Clearly, more research is needed to clarify the expression and role of miRNAs in sepsis, and to promote the use of miRNAs for sepsis management.

Regulatory Role of Non-Coding RNAs on Immune Responses During Sepsis

Sepsis is resulted from a systemic inflammatory response to bacterial, viral, or fungal agents. The induced inflammatory response by these microorganisms can lead to multiple organ system failure with devastating consequences. Recent studies have shown altered expressions of several non-coding RNAs such as long non-coding RNAs (lncRNAs), microRNAs (miRNAs) and circular RNAs (circRNAs) during sepsis. These transcripts have also been found to participate in the pathogenesis of multiple organ system failure through different mechanisms. NEAT1, MALAT1, THRIL, XIST, MIAT and TUG1 are among lncRNAs that participate in the pathoetiology of sepsis-related complications. miR-21, miR-155, miR-15a-5p, miR-494-3p, miR-218, miR-122, miR-208a-5p, miR-328 and miR-218 are examples of miRNAs participating in these complications. Finally, tens of circRNAs such as circC3P1, hsa_circRNA_104484, hsa_circRNA_104670 and circVMA21 and circ-PRKCI have been found to affect pathogenesis of sepsis. In the current review, we describe the role of these three classes of noncoding RNAs in the pathoetiology of sepsis-related complications.

Regulatory network of miRNA, lncRNA, transcription factor and target immune response genes in bovine mastitis

Pre- and post-transcriptional modifications of gene expression are emerging as foci of disease studies, with some studies revealing the importance of non-coding transcripts, like long non-coding RNAs (lncRNAs) and microRNAs (miRNAs). We hypothesize that transcription factors (TFs), lncRNAs and miRNAs modulate immune response in bovine mastitis and could potentially serve as disease biomarkers and/or drug targets. With computational analyses, we identified candidate genes potentially regulated by miRNAs and lncRNAs base pair complementation and thermodynamic stability of binding regions. Remarkably, we found six miRNAs, two being bta-miR-223 and bta-miR-24-3p, to bind to several targets. LncRNAs NONBTAT027932.1 and XR_003029725.1, were identified to target several genes. Functional and pathway analyses revealed lipopolysaccharide-mediated signaling pathway, regulation of chemokine (C-X-C motif) ligand 2 production and regulation of IL-23 production among others. The overarching interactome deserves further in vitro/in vivo explication for specific molecular regulatory mechanisms during bovine mastitis immune response and could lay the foundation for development of disease markers and therapeutic intervention.

Long noncoding RNAs: A potential target in sepsis-induced cellular disorder

Sepsis, an inflammation-related clinical syndrome, is characterized by disrupted immune homeostasis accompanied by infection and multiple organ dysfunction as determined by the Sequential Organ Failure Assessment (SOFA). Substantial evidence has recently suggested that lncRNAs orchestrate various biological processes in diseases, and lncRNAs play special roles in the diagnosis and management of sepsis. To date, very few reviews have provided clear and comprehensive clues to demonstrate the roles of lncRNAs in the pathogenesis of sepsis. Based on previously published studies, in this review, we summarize the different functions of lncRNAs in sepsis-induced cellular disorders and sepsis-induced organ failure to show the potential roles of lncRNAs in the diagnosis and management of sepsis. We further depict the function of some lncRNAs known to be pivotal regulators in the pathogenesis of sepsis to discuss the underlying molecular events. Additionally, we list and discuss several hotspots in research on lncRNAs, which may be conducive to future lncRNA-targeted therapeutic approaches for sepsis treatment.

Circ_0057452 functions as a ceRNA in hypertrophic scar fibroblast proliferation and VEGF expression by regulating TGF-β2 expression and adsorbing miR-145-5p

OBJECTIVE

To explore the mechanism by which circ_0057452/miR-145-5p/TGF-β2 axis regulates fibroblast proliferation as well as VEGF expression in hypertrophic scars (HS).

METHODS

The expression of circ_0057452, miR-145-5p and TGF-β2 in HS tissues and fibroblasts was measured by quantitative real-time Polymerase Chain Reaction (qRT-PCR). The targeting relations between circ_0057452 and miR-145-5p, miR-145-5p and TGF-β2 were identified using dual-luciferase reporter assay. The expression of circ_0057452, miR-145-5p and TGF-β2 in fibroblasts was interfered with and cells were grouped. In each group, changes in cell proliferation were detected using CCK8 assay, apoptosis was measured by flow cytometry, and VEGF secreted in cell culture supernatant was tested by ELISA kit.

RESULTS

Compared with normal tissues and fibroblasts, the expressions of circ_0057452 and TGF-β2 were increased and miR-145-5p decreased in HS tissues and cells (all P<0.05). Compared with the si-NC group, cell proliferation and VEGF expressions were decreased and the apoptotic rate increased in the si_circ_0057452 group (all P<0.05). Compared with the oe-NC group, cell proliferation and VEGF expression were increased and the apoptotic rate decreased in the oe-circ_0057452 group (all P<0.05). Compared with the oe-circ_0057452 + miR-NC group, the number of apoptotic cells was increased, and cell proliferation, as well as VEGF expression were decreased in the oe-circ_0057452 + miR-145-5p mimic group (all P<0.05). Compared with the miR-NC group, cell proliferation and VEGF expression were reduced and the apoptotic rate was increased in the miR-145-5p mimic group (all P<0.05). Compared with the miR-145-5p mimic + vector group, cell proliferation and VEGF expression were elevated, and apoptosis was inhibited in the miR-145-5p mimic + TGF-β2 group (all P<0.05).

CONCLUSION

circ_0057452 can competitively bind miR-145-5p to induce the expression of TGF-β2, and then promote the proliferation of HS fibroblasts and secretion of VEGF, which is expected to be effective in the treatment of HS.