Long non-coding RNA NEAT1 contributes to lipopolysaccharide-induced inflammation and apoptosis of human middle ear epithelial cells via regulating the miR-301b-3p/TLR4 axis

Roles of long noncoding RNAs in human inflammatory diseases

Chemokines, cytokines, and inflammatory cells mediate the onset and progression of many diseases through the induction of an inflammatory response. LncRNAs have emerged as important regulators of gene expression and signaling pathways. Increasing evidence suggests that lncRNAs are key players in the inflammatory response, making it a potential therapeutic target for various diseases. From the perspective of lncRNAs and inflammatory factors, we summarized the expression level and regulatory mechanisms of lncRNAs in human inflammatory diseases, such as cardiovascular disease, osteoarthritis, sepsis, chronic obstructive pulmonary disease, asthma, acute lung injury, diabetic retinopathy, and Parkinson's disease. We also summarized the functions of lncRNAs in the macrophages polarization and discussed the potential applications of lncRNAs in human inflammatory diseases. Although our understanding of lncRNAs is still in its infancy, these data will provide a theoretical basis for the clinical application of lncRNAs.

Construction of an immune-related lncRNA-miRNA-mRNA regulatory network in radiation-induced esophageal injury in rats

Radiation-induced esophageal injury (RIEI) is an adverse reaction of radiation therapy in patients with esophageal cancer, lung cancer and other malignant tumors. Competitive endogenous RNA (ceRNA) network is known to play a significant role in the onset and progression of many diseases, but the exact mechanism of ceRNA in RIEI has not been fully elucidated. In this study, rat esophaguses were obtained after conducting irradiation under different doses (0 Gy, 25 Gy, 35 Gy). Total RNA was extracted and mRNA, lncRNA, circRNA, and miRNA sequencing was performed. Multiple dose-dependent differentially expressed RNAs (dd-DERs), including 870 lncRNAs, 82 miRNAs, 2478 mRNAs, were obtained through the integration of differential expression analysis and dose-dependent screening (35 Gy ≥ 25 Gy > 0 Gy, or 35 Gy ≤ 25 Gy < 0 Gy). Co-expression analysis and prediction of the binding site in dd-DER were conducted and 27 lncRNAs, 20 miRNAs, and 168 mRNAs were selected to construct a ceRNA network. As the immune microenvironment is crucial for RIEI progression, we constructed an immune-related ceRNA network consisting of 11 lncRNAs, 9 miRNAs, and 9 mRNAs. The expression levels of these immune-related RNAs were verified by RT-qPCR. Immune infiltration analysis showed that the RNAs in the immune-related ceRNA network were mainly associated with the proportion of monocytes, M2 macrophages, activated NK cells, and activated CD4+ memory T cells. Drug sensitivity analysis was conducted based on the expression levels of mRNAs in the immune-related ceRNA network, and small molecule drugs with preventive and therapeutic effects on RIEI were identified. In summary, an immune-related ceRNA network associated with RIEI progression was constructed in this study. The findings provide useful information on new potential targets for the prevention and treatment of RIEI.

CircRNA RERE Promotes the Oxidative Stress-Induced Apoptosis and Autophagy of Nucleus Pulposus Cells through the miR-299-5p/Galectin-3 Axis

Intervertebral disc degeneration (IDD) is widely accepted as a cause of low back pain and related degenerative musculoskeletal disorders. Nucleus pulposus (NP) cell loss is closely related to IDD progression. Thus, investigating the specifically targeted therapeutic agents against NP cell loss depends on understanding the molecular mechanisms. In this study, human NP cells were treated with hydrogen peroxide (H2O2). Cell viability was assessed by using the Cell Counting Kit-8 (CCK-8) kit. The expression of circRNA arginine-glutamic acid dipeptide repeats (hsa_circ_RERE) and miR-299-5p was analyzed by real-time quantitative PCR. Western blot analysis was used to assess the protein expression levels. The autophagy levels in NP cells were detected by using an electronic microscope, LC3B protein immunofluorescence, and western blot. The apoptosis levels of NP cells were detected by flow cytometry and western blot. Dual-luciferase reporter assay analyzed the miR-299-5p bound to circ_RERE and galectin-3. Our results revealed that H2O2 significantly inhibited the viability of NP cells, promoted apoptosis and autophagy, and upregulated galectin-3 expression. miR-299-5p was reduced in IDD and H2O2-induced NP cells. The overexpression of miR-299-5p promoted cell viability and attenuated apoptosis and autophagy under H2O2 treatment. Besides, circ_RERE was upregulated in IDD and H2O2-induced NP cells. However, knockdown of circ_RERE reversed the effects of miR-299-5p overexpression on cell viability, apoptosis, and autophagy in NP cells. We propose that circ_RERE promotes the H2O2-induced apoptosis and autophagy of NP cells through the miR-299-5p/galectin-3 axis and may provide a new target for the clinical treatment of IDD.