miR-489 inhibits silica-induced pulmonary fibrosis by targeting MyD88 and Smad3 and is negatively regulated by lncRNA CHRF

LncRNA MRAK052509 competitively adsorbs miR-204-3p to regulate silica dust-induced EMT process

Silicosis is a systemic disease caused by long-term inhalation of free SiO2 and retention in the lungs. At present, it is still the most important occupational health hazard disease in the world. Existing studies have shown that non-coding RNA can also participate in complex fibrosis regulatory networks. However, its role in regulating silicotic fibrosis is still unclear. In this study, we constructed a NR8383/RLE-6TN co-culture system to simulate the pathogenesis of silicosis in vitro. Design of miR-204-3p mimics and inhibitors to overexpress or downregulate miR-204-3p in RLE-6TN cells. Design of short hairpin RNA (sh-RNA) to downregulate MRAK052509 in RLE-6TN cells. The regulatory mechanism of miR-204-3p and LncRNA MRAK052509 on EMT process was studied by Quantitative real-time PCR, Western blotting, Immunofluorescence and Cell scratch test. The results revealed that miR-204-3p affects the occurrence of silica dust-induced cellular EMT process mainly through regulating TGF-βRΙ, a key molecule of TGF-β signaling pathway. In contrast, Lnc MRAK052509 promotes the EMT process in epithelial cells by competitively adsorbing miR-204-3p and reducing its inhibitory effect on the target gene TGF-βRΙ, which may influence the development of silicosis fibrosis. This study perfects the targeted regulation relationship between LncRNA MRAK052509, miR-204-3p and TGF-βRΙ, and may provide a new strategy for the study of the pathogenesis and treatment of silicosis.

Roles of lncRNAs in NF-κB-Mediated Macrophage Inflammation and Their Implications in the Pathogenesis of Human Diseases

Over the past century, molecular biology's focus has transitioned from proteins to DNA, and now to RNA. Once considered merely a genetic information carrier, RNA is now recognized as both a vital element in early cellular life and a regulator in complex organisms. Long noncoding RNAs (lncRNAs), which are over 200 bases long but do not code for proteins, play roles in gene expression regulation and signal transduction by inducing epigenetic changes or interacting with various proteins and RNAs. These interactions exhibit a range of functions in various cell types, including macrophages. Notably, some macrophage lncRNAs influence the activation of NF-κB, a crucial transcription factor governing immune and inflammatory responses. Macrophage NF-κB is instrumental in the progression of various pathological conditions including sepsis, atherosclerosis, cancer, autoimmune disorders, and hypersensitivity. It orchestrates gene expression related to immune responses, inflammation, cell survival, and proliferation. Consequently, its malfunction is a key contributor to the onset and development of these diseases. This review aims to summarize the function of lncRNAs in regulating NF-κB activity in macrophage activation and inflammation, with a particular emphasis on their relevance to human diseases and their potential as therapeutic targets. The insights gained from studies on macrophage lncRNAs, as discussed in this review, could provide valuable knowledge for the development of treatments for various pathological conditions involving macrophages.

Integrated mRNA and microRNA profiling in lung tissue and blood from human silicosis

BACKGROUND

The overwhelming majority of subjects in the current silicosis mRNA and microRNA (miRNA) expression profile are of human blood, lung cells or a rat model, which puts limits on the understanding of silicosis pathogenesis and therapy. To address the limitations, our investigation was focused on differentially expressed mRNA and miRNA profiles in lung tissue from silicosis patients to explore potential biomarker for early detection of silicosis.

METHODS

A transcriptome study was conducted based on lung tissue from 15 silicosis patients and eight normal people, and blood samples from 404 silicosis patients and 177 normal people. Three early stage silicosis, five advanced silicosis and four normal lung tissues were randomly selected for microarray processing and analyze. The differentially expressed mRNAs were further used to conduct Gene Ontology and pathway analyses. Series test of cluster was performed to explore possible changes in differentially expressed mRNA and miRNA expression patterns during the process of silicosis. The blood samples and remaining lung tissues were used in a quantitative real-time PCR (RT-qPCR) (RT-qPCR).

RESULTS

In total, 1417 and 241 differentially expressed mRNAs and miRNAs were identified between lung tissue from silicosis patients and normal people (p < 0.05). However, there was no significant difference in most mRNA or miRNA expression between early stage and advanced stage silicosis lung tissues. RT-qPCR validation results in lung tissues showed expression of four mRNAs (HIF1A, SOCS3, GNAI3 and PTEN) and seven miRNAs was significantly down-regulated compared to those of control group. Nevertheless, PTEN and GNAI3 expression was significantly up-regulated (p < 0.001) in blood samples. The bisulfite sequencing PCR demonstrated that PTEN had significantly decreased the methylation rate in blood samples of silicosis patients.

CONCLUSIONS

PTEN might be a potential biomarker for silicosis as a result of low methylation in the blood.

Ginsenoside Re inhibits myocardial fibrosis by regulating miR-489/myd88/NF-κB pathway

Background

Myocardial fibrosis (MF) is an advanced pathological manifestation of many cardiovascular diseases, which can induce heart failure and malignant arrhythmias. However, the current treatment of MF lacks specific drugs. Ginsenoside Re has anti-MF effect in rat, but its mechanism is still not clear. Therefore, we investigated the anti-MF effect of ginsenoside Re by constructing mouse acute myocardial infarction (AMI) model and AngⅡ induced cardiac fibroblasts (CFs) model.

Methods

The anti-MF effect of miR-489 was investigated by transfection of miR-489 mimic and inhibitor in CFs. Effect of ginsenoside Re on MF and its related mechanisms were investigated by ultrasonographic, ELISA, histopathologic staining, transwell test, immunofluorescence, Western blot and qPCR in the mouse model of AMI and the AngⅡ-induced CFs model.

Results

MiR-489 decreased the expression of α-SMA, collagenⅠ, collagen Ⅲ and myd88, and inhibited the phosphorylation of NF-κB p65 in normal CFs and CFs treated with AngⅡ. Ginsenoside Re could improve cardiac function, inhibit collagen deposition and CFs migration, promote the transcription of miR-489, and reduce the expression of myd88 and the phosphorylation of NF-κB p65.

Conclusion

MiR-489 can effectively inhibit the pathological process of MF, and the mechanism is at least partly related to the regulation of myd88/NF-κB pathway. Ginsenoside Re can ameliorate AMI and AngⅡ induced MF, and the mechanism is at least partially related to the regulation of miR-489/myd88/NF-κB signaling pathway. Therefore, miR-489 may be a potential target of anti-MF and ginsenoside Re may be an effective drug for the treatment of MF.

Long noncoding RNA MyD88 functions as a promising diagnostic biomarker in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most frequent malignancies. Alpha-fetoprotein (AFP) has some limitations in diagnosing early HCC. Recently, long noncoding RNAs (lncRNAs) showed great potential as tumor diagnostic biomarkers, and lnc-MyD88 was previously identified as a carcinogen in HCC. Here, we explored its diagnostic value as a plasma biomarker.

MATERIALS AND METHODS

Quantitative real-time PCR was adopted to detect lnc-MyD88 expression in plasma samples of 98 HCC patients, 52 liver cirrhosis (LC) patients, and 105 healthy people. The correlation between lnc-MyD88 and clinicopathological factors was analyzed through chi-square test. The receiver operating characteristic (ROC) curve was used to analyze the sensitivity, specificity, Youden index, and area under the curve (AUC) of lnc-MyD88 and AFP alone and in combination for the diagnosis of HCC. The relationship between MyD88 and immune infiltration was analyzed by single sample gene set enrichment analysis (ssGSEA) algorithm.

RESULTS

Lnc-MyD88 was highly expressed in plasma samples of HCC and hepatitis B virus (HBV)-associated HCC patients. Lnc-MyD88 had better diagnostic value than AFP in HCC patients using healthy people or LC patients as control (healthy people, AUC: 0.776 vs. 0.725; LC patients, AUC: 0.753 vs. 0.727). The multivariate analysis showed that lnc-MyD88 had great diagnostic value for distinguishing HCC from LC and healthy people. Lnc-MyD88 had no correlation with AFP. Lnc-MyD88 and AFP were independent diagnostic factors for HBV-associated HCC. The AUC, sensitivity, and Youden index of the combined diagnosis of lnc-MyD88 and AFP combined were higher than those of lnc-MyD88 and AFP alone. The ROC curve of lnc-MyD88 for the diagnosis of AFP-negative HCC was plotted with a sensitivity of 80.95%, a specificity of 79.59%, and an AUC value of 0.812 using healthy people as control. The ROC curve also presented its great diagnostic value using LC patients as control (sensitivity: 76.19%, specificity: 69.05%, AUC value: 0.769). Lnc-MyD88 expression was correlated with microvascular invasion in HBV-associated HCC patients. MyD88 was positively correlated with infiltrating immune cells and immune-related genes.

CONCLUSION

The high expression of plasma lnc-MyD88 in HCC is distinct and could be utilized as a promising diagnostic biomarker. Lnc-MyD88 had great diagnostic value for HBV-associated HCC and AFP-negative HCC, and it had higher efficacy in combination with AFP.

The emerging role of epigenetic regulation in the progression of silicosis

Silicosis is one of the most severe occupational diseases worldwide and is characterized by silicon nodules and diffuse pulmonary fibrosis. However, specific treatments for silicosis are still lacking at present. Therefore, elucidating the pathogenesis of silicosis plays a significant guiding role for its treatment and prevention. The occurrence and development of silicosis are accompanied by many regulatory mechanisms, including epigenetic regulation. The main epigenetic regulatory mechanisms of silicosis include DNA methylation, non-coding RNA (ncRNA), and histone modifications. In recent years, the expression and regulation of genes related to silicosis have been explored at epigenetic level to reveal its pathogenesis further, and the identification of aberrant epigenetic markers provides new biomarkers for prediction and diagnosis of silicosis. Here, we summarize the studies on the role of epigenetic changes in the pathogenesis of silicosis to give some clues for finding specific therapeutic targets for silicosis.

SIS3 Alleviates Cisplatin-Induced Acute Kidney Injury by Regulating the LncRNA Arid2-IR-Transferrin Receptor Pathway

INTRODUCTION

TGF-β/Smad3 may be involved in the pathogenesis of acute kidney injury (AKI), but its functional role and mechanism of action in cisplatin-induced AKI are unclear. Here, we established a cisplatin-induced AKI mouse model to demonstrate that Smad3 may have roles in cisplatin nephropathy because of its potential effects on tubular epithelial cell (TEC) death and regeneration.

METHODS

Using a cisplatin-induced AKI model, the expression levels of lncRNA Arid2-IR were measured by qRT-PCR and the location detected by FISH. Transfected with overexpression of lncRNA Arid2-IR by lentiviral vector in TECs, and the expression of cleaved caspase 3, Bax, Bcl-2, PCNA, p21, p27, transferrin receptor (TFRC), FTH, and FTL were measured by Western blot. Protein molecules bound to lncRNA Arid2-IR were identified by RIP, RNA pull-down assay, mass spectrometry.

RESULTS

LncRNA Arid2-IR was significantly downregulated in vivo and in vitro. SIS3 decreased cell apoptosis and promoted cell regeneration by upregulating lncRNA Arid2-IR expression. LncRNA Arid2-IR regulated the cell cycle by decreasing expression of the cyclin-dependent kinase inhibitors p21 and p27. Finally, lncRNA Arid2-IR interacted with the TFRC, and overexpression of lncRNA Arid2-IR increased TFRC expression and decreased FTH and FTL.

CONCLUSION

Smad3 regulated lncRNA Arid2-IR via TFRC, thereby regulating the cell cycle, protecting against cell apoptosis, and promoting cell regeneration.

Long Non-Coding RNAs in Cardiac and Pulmonary Fibroblasts and Fibrosis

The cardiopulmonary system delivers oxygen throughout the body via blood circulation. It is an essential part of the body to sustain the lives of organisms. The integral parts of the cardiopulmonary system—the heart and lungs—are constantly exposed to damaging agents (e.g., dust, viruses), and can be greatly affected by injuries caused by dysfunction in tissues (e.g., myocardial infarction). When damaged, mesenchymal cells, such as fibroblasts, are activated to become myofibroblasts to initiate fibrosis as part of a regenerative mechanism. In diseased states, the excess accumulation of extracellular matrices secreted by myofibroblasts results in further dysfunction in the damaged organs. These fibrotic tissues cannot easily be removed. Thus, there is a growing interest in understanding the fibrotic process, as well as finding biomolecules that can be targets for slowing down or potentially stopping fibrosis. Among these biomolecules, the interest in studying long non-coding RNAs (lncRNAs; any non-protein-coding RNAs longer than 200 nucleotides) has intensified in recent years. In this commentary, we summarize the current status of lncRNA research in the cardiopulmonary system by focusing on cardiac and pulmonary fibrosis.

Downregulation of lncRNA Miat contributes to the protective effect of electroacupuncture against myocardial fibrosis

Background

Myocardial fibrosis changes the structure of myocardium, leads to cardiac dysfunction and induces arrhythmia and cardiac ischemia, threatening patients’ lives. Electroacupuncture at PC6 (Neiguan) was previously found to inhibit myocardial fibrosis. Long non-coding RNAs (lncRNAs) play a variety of regulatory functions in myocardial fibrosis, but whether electroacupuncture can inhibit myocardial fibrosis by regulating lncRNA has rarely been reported.

Methods

In this study, we constructed myocardial fibrosis rat models using isoproterenol (ISO) and treated rats with electroacupuncture at PC6 point and non-point as control. Hematoxylin–eosin, Masson and Sirius Red staining were performed to assess the pathological changes and collagen deposition. The expression of fibrosis-related markers in rat myocardial tissue were detected by RT-qPCR and Western blot. Miat, an important long non-coding RNA, was selected to study the regulation of myocardial fibrosis by electroacupuncture at the transcriptional and post-transcriptional levels. In post-transcriptional level, we explored the myocardial fibrosis regulation effect of Miat on the sponge effect of miR-133a-3p. At the transcriptional level, we studied the formation of heterodimer PPARG–RXRA complex and promotion of the TGF-β1 transcription.

Results

Miat was overexpressed by ISO injection in rats. We found that Miat can play a dual regulatory role in myocardial fibrosis. Miat can sponge miR-133a-3p in an Ago2-dependent manner, reduce the binding of miR-133a-3p target to the 3ʹUTR region of CTGF mRNA and improve the protein expression level of CTGF. In addition, it can also directly bind with PPARG protein, inhibit the formation of heterodimer PPARG–RXRA complex and then promote the transcription of TGF-β1. Electroacupuncture at PC6 point, but not at non-points, can reduce the expression of Miat, thus inhibiting the expression of CTGF and TGF-β1 and inhibiting myocardial fibrosis.

Conclusion

We revealed that electroacupuncture at PC6 point can inhibit the process of myocardial fibrosis by reducing the expression of lncRNA Miat, which is a potential therapeutic method for myocardial fibrosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-022-00615-6.

Long non-coding RNA HCG18 promotes gastric cancer progression by regulating miRNA-146a-5p/tumor necrosis factor receptor-associated factor 6 axis

Although long non-coding RNAs (lncRNAs) have been demonstrated to be dysregulated in gastric cancer (GC), the function of lncRNA HCG18 (HCG18) in GC is elusive. Therefore, the study was designed to evaluate the underlying mechanism of HCG18 in GC. HCG18 and microRNA 146a-5p (miR-146a-5p) levels in GC were evaluated by RT-qPCR. The effects of miR-146a-5p and HCG18 on GC cell function were examined using Transwell assay, colony formation, and CCK-8 assays. Tumor necrosis factor receptor-associated factor 6 (TRAF6) and p65 expression levels were detected by Western blot. HCG18 and miR-146a-5p target genes were identified using luciferase reporter and bioinformatics assays. HCG18 expression was increased in GC. HCG18 overexpression significantly increased GC cell proliferation, invasion, and migration. Furthermore, HCG18 overexpression inhibited miR-146a-5p and upregulated TRAF6 and p65 expression. Finally, miR-146a-5p/TRAF6 was found to be involved in the role of HCG18 in GC progression in vivo. Altogether, HCG18 promotes GC progression via the miR-146a-5p/TRAF6 axis and could be a GC treatment target.

Microcrystalline silica particles induce inflammatory response via pyroptosis in primary human respiratory epithelial cells

The mechanism of the sterile inflammatory response in the respiratory tract induced by exposure to sterile particles has not been fully elucidated. The aim of our study is to explore the earlier events in initiating inflammatory response at molecular and cellular level in primary cultured human airway epithelial cells (AEC) exposed to silica particles in order to provide information for earlier diagnosis and prevention of silica particle-induced toxicity as well as possible information on the genesis of silicosis. We isolated primary AEC from three healthy adults and treated them with silica particles at different concentrations for 48 h. We found evidence for silica-induced inflammasome activation by the co-localization of Caspase-1 and NLRP3, as well as increased levels of IL-1β and IL-18. Lactate dehydrogenase and NucGreen analysis proved the occurrence of pyroptosis. High throughput mRNA sequencing showed that the inflammatory response and NF-κB signaling pathways were significantly enriched in gene ontology and Kyoto encyclopedia of genes and genomes analysis, and pyroptosis-related genes were up-regulated. The miR-455-3p and five lncRNAs (LOC105375913, NEAT1, LOC105375181, LOC100506098, and LOC105369370) were verified as key factors related to the mechanism by ceRNA network analysis. LOC105375913 was first discovered to be associated with inflammation in AEC. These data suggest that microcrystalline silica can induce significant inflammation and pyroptosis in human primary AEC through NLRP3 inflammasome pathway and NF-κB signaling pathway at both the gene and protein levels, and the possible mechanism could be miR-455-3p mediated ceRNA hypothesis. Our data provide a method for the studies of the respiratory toxicity of fine particulate matter and the pathogenesis of early silicosis. The miR-455-3p and five lncRNAs related ceRNA network might be the toxicity mechanism of microcrystalline silica particles to AEC.

Long noncoding RNA Lnc-DIF inhibits bone formation by sequestering miR-489-3p

Osteoporosis has become a high incident bone disease along with the aging of human population. Long noncoding RNAs (LncRNAs) play an important role in osteoporosis incidence. In this study, we screened out an LncRNA negatively correlated with osteoblast differentiation, which was therefore named Lnc-DIF (differentiation inhibiting factor). Functional analysis proved that Lnc-DIF inhibited bone formation. A special structure containing multiple 53 nucleotide repeats was found in the trailing end of Lnc-DIF. Our study suggested that this repeat sequence could sequester multiple miR-489-3p and inhibit bone formation through miR-489-3p/SMAD2 axis. Moreover, siRNA of Lnc-DIF would rescue bone formation in both aging and ovariectomized osteoporosis mice. This study revealed a kind of LncRNA that could function as a sponge and regulate multiple miRNAs. RNA therapy techniques that target these LncRNAs could manipulate its downstream miRNA-target pathway with significantly higher efficiency and specificity. This provided potential therapeutic insight for RNA-based therapy for osteoporosis.

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Identified LncRNA Lnc-DIF that inhibited bone formation

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Lnc-DIF sequestered multiple miR-489-3p by the repeat sequences on its trailing end

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Lnc-DIF repeat sequence inhibited bone formation via miR-489-3p/SMAD2 axis

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Lnc-DIF siRNA showed strong capability on rescuing osteoporosis

Epigenetic Changes and Functions in Pneumoconiosis

Pneumoconiosis is one of the most common occupational diseases in the world, and specific treatment methods of pneumoconiosis are lacking at present, so it carries great social and economic burdens. Pneumoconiosis, coronavirus disease 2019, and idiopathic pulmonary fibrosis all have similar typical pathological changes-pulmonary fibrosis. Pulmonary fibrosis is a chronic lung disease characterized by excessive deposition of the extracellular matrix and remodeling of the lung tissue structure. Clarifying the pathogenesis of pneumoconiosis plays an important guiding role in its treatment. The occurrence and development of pneumoconiosis are accompanied by epigenetic factors (e.g., DNA methylation and noncoding RNA) changes, which in turn can promote or inhibit the process of pneumoconiosis. Here, we summarize epigenetic changes and functions in the several kinds of evidence classification (epidemiological investigation, in vivo, and in vitro experiments) and main types of cells (macrophages, fibroblasts, and alveolar epithelial cells) to provide some clues for finding specific therapeutic targets for pneumoconiosis and even for pulmonary fibrosis.

The single nucleotide polymorphism rs1814521 in long non-coding RNA ADGRG3 associates with the susceptibility to silicosis: a multi-stage study

Background

This study aimed to evaluate the correlation between long non-coding RNA (lncRNA)-related single nucleotide polymorphisms (SNPs) and susceptibility to silicosis.

Methods

First, RNA-sequencing (RNA-seq) data were comprehensively analyzed in the peripheral blood lymphocytes of eight participants (four silicosis cases and four healthy controls) exposed to silica dust to identify differentially expressed lncRNAs (DE-lncRNAs). The functional SNPs in the identified DE-lncRNAs were then identified using several databases. Finally, the association between functional SNPs and susceptibility to silicosis was evaluated by a two-stage case-control study. The SNPs of 155 silicosis cases and 141 healthy silica-exposed controls were screened by genome-wide association study (GWAS), and the candidate SNPs of 194 silicosis cases and 235 healthy silica-exposed controls were validated by genotyping using the improved Mutiligase Detection Reaction (iMLDR) system.

Results

A total of 76 DE-lncRNAs were identified by RNA-seq data analysis (cut-offs: fold change > 2 or fold change < 0.5, P < 0.05), while 127 functional SNPs among those 76 DE-lncRNAs were identified through multiple public databases. Furthermore, five SNPs were found to be significantly correlated with the risk of silicosis by GWAS screening (P < 0.05), while the results of GWAS and iMLDR validation indicated that the variant A allele of rs1814521 was associated with a reduced risk of silicosis (OR = 0.76, 95% CI = 0.62–0.94, P = 0.011).

Conclusion

The presence of the SNP rs1814521 in the lncRNA ADGRG3 is associated with susceptibility to silicosis. Moreover, ADGRG3 was found to be lowly expressed in silicosis cases. The underlying biological mechanisms by which lncRNA ADGRG3 and rs1814521 regulate the development of silicosis need further study.

Supplementary information

The online version contains supplementary material available at https://doi.org/10.1265/ehpm.21-00338.

Non-coding RNA-based regulation of inflammation

Inflammation is a multifactorial process and various biological mechanisms and pathways participate in its development. The presence of inflammation is involved in pathogenesis of different diseases such as diabetes mellitus, cardiovascular diseases and even, cancer. Non-coding RNAs (ncRNAs) comprise large part of transcribed genome and their critical function in physiological and pathological conditions has been confirmed. The present review focuses on miRNAs, lncRNAs and circRNAs as ncRNAs and their potential functions in inflammation regulation and resolution. Pro-inflammatory and anti-inflammatory factors are regulated by miRNAs via binding to 3'-UTR or indirectly via affecting other pathways such as SIRT1 and NF-κB. LncRNAs display a similar function and they can also affect miRNAs via sponging in regulating levels of cytokines. CircRNAs mainly affect miRNAs and reduce their expression in regulating cytokine levels. Notably, exosomal ncRNAs have shown capacity in inflammation resolution. In addition to pre-clinical studies, clinical trials have examined role of ncRNAs in inflammation-mediated disease pathogenesis and cytokine regulation. The therapeutic targeting of ncRNAs using drugs and nucleic acids have been analyzed to reduce inflammation in disease therapy. Therefore, ncRNAs can serve as diagnostic, prognostic and therapeutic targets in inflammation-related diseases in pre-clinical and clinical backgrounds.

Long Noncoding RNAs Regulate the Inflammatory Responses of Macrophages

Long noncoding RNAs (lncRNAs) are defined as transcripts with more than 200 nucleotides that have little or no coding potential. In recent years, due to the development of next-generation sequencing (NGS), a large number of studies have revealed that lncRNAs function as key regulators to maintain immune balance and participate in diverse physiological and pathological processes in the human body. Notably, overwhelming evidence suggests that lncRNAs can regulate innate immune responses, the differentiation and development of immune cells, inflammatory autoimmune diseases, and many other immunological processes with distinct regulatory mechanisms. In this review, we summarized the emerging roles of lncRNAs in macrophage development and polarization. In addition, the potential value of lncRNAs as diagnostic biomarkers and novel therapeutic targets for the treatment of aberrant immune responses and inflammatory diseases are discussed.

Revealing the role of miRNA-489 as a new onco-suppressor factor in different cancers based on pre-clinical and clinical evidence

Recently, microRNAs (miRNAs) have shown to be potential therapeutic, diagnostic and prognostic targets in disease therapy. These endogenous non-coding RNAs contribute to regulation of different cellular events that are necessary for maintaining physiological condition. Dysregulation of miRNAs is correlated with development of various pathological events such as neurological disorders, cardiovascular diseases, and cancer. miRNA-489 is a new emerging miRNA and studies are extensively investigating its role in pathological conditions. Herein, potential function of miRNA-489 as tumor-suppressor in various cancers is described. miRNA-489 is able to sensitize cancer cells into chemotherapy by disrupting molecular pathways involved in cancer growth such as PI3K/Akt, and induction of apoptosis. The PROX1 and SUZ12 as oncogenic pathways, are affected by miRNA-489 in suppressing metastasis of cancer cells. Wnt/β-catenin as an oncogenic factor ensuring growth and malignancy of tumors is inhibited via miRNA-489 function. For enhancing drug sensitivity of tumors, restoring miRNA-489 expression is a promising strategy. The lncRNAs can modulate miRNA-489 expression in tumors and studies about circRNA role in miRNA-489 modulation should be performed. The expression level of miRNA-489 is a diagnostic tool for tumor detection. Besides, down-regulation of miRNA-489 in tumors provides unfavorable prognosis.

Long non-coding RNA SNHG1 promotes fibroblast-to-myofibroblast transition during the development of pulmonary fibrosis induced by silica particles exposure

Inhaling silica dust in the environment can cause progressive pulmonary fibrosis, then silicosis. Silicosis is the most harmful occupational disease in the world, so the study of the mechanism is of great significance for the prevention and treatment of silicosis. Long non-coding RNAs (lncRNAs) are important players in the pathological process of fibrotic diseases. However, the function of specific lncRNA in regulating pulmonary fibrosis remains elusive. In this study, a mouse model of pulmonary fibrosis via intratracheal instillation of silica particles was established, and the differential expression of lnc-SNHG1 and miR-326 in lung tissues and TGF-β1-treated fibroblasts was detected by the qRT-PCR method. Short interfering RNA (siRNA) and plasmid were designed for knockdown or overexpression of lnc-SNHG1 in fibroblasts. MiRNA simulant was designed for overexpression of miR-326 in vivo and in vitro. Dual-luciferase reporter system, immunofluorescence, western blot, wound healing and transwell assay were performed to investigate the function and the underlying mechanisms of lnc-SNHG1. As a result, we found that lnc-SNHG1 was highly expressed in fibrotic lung tissues of mice and TGF-β1-treated fibroblasts. Moreover, the high expression of lnc-SNHG1 facilitated the migration and invasion of fibroblasts and the secretion of fibrotic molecules, while the low expression of lnc-SNHG1 exerted the opposite effects. Further mechanism studies showed that miR-326 was the potential target of lnc-SNHG1, and there is a negative correlation between the expression levels of lnc-SNHG1 and miR-326. Combined with mitigating fibrotic effects of miR-326 in a mouse model of silica particles exposure, we revealed that lnc-SNHG1 significantly sponged miR-326 and facilitated the expression of SP1, thus accelerating fibroblast-to-myofibroblast transition and synergistically promoting the development of pulmonary fibrosis. Our study uncovered a key mechanism by which lnc-SNHG1 regulated pulmonary fibrosis through miR-326/SP1 axis, and lnc-SNHG1 is a potential target for the prevention and treatment of silicosis.

Idiopathic Pulmonary Comorbidities and Mechanisms

Idiopathic pulmonary fibrosis (IPF) is a disease with an unknown etiology mainly characterized by a progressive decline of lung function due to the scarring of the tissue deep in the lungs. The overall survival after diagnosis remains low between 3 and 5 years. IPF is a heterogeneous disease and much progress has been made in the past decade in understanding the disease mechanisms that contributed to the development of two new drugs, pirfenidone and nintedanib, which improved the therapeutic management of the disease. The understanding of the cofactors and comorbidities of IPF also contributed to improved management of the disease outcome. In the present review, we evaluate scientific evidence which indicates IPF as a risk factor for other diseases based on the complexity of molecular and cellular mechanisms involved in the disease development and of comorbidities. We conclude from the existing literature that while much progress has been made in understating the mechanisms involved in IPF development, further studies are still necessary to fully understand IPF pathogenesis which will contribute to the identification of novel therapeutic targets for IPF management as well as other diseases for which IPF is a major risk factor.

miR-489-3p overexpression inhibits lipopolysaccharide-induced nucleus pulposus cell apoptosis, inflammation and extracellular matrix degradation via targeting Toll-like receptor 4

Intervertebral disc degeneration (IDD) is a common disease with a high morbidity rate, which results in a significant deterioration in the quality of life of patients. MicroRNAs (miRNAs/miRs) are a class of endogenous small non-coding RNAs that influence target genes and serve critical roles in numerous biological processes. However, the role of miR-489-3p in lumbar disc degeneration is yet to be elucidated. In the present study, human NP cells were treated with 10 ng/ml lipopolysaccharide (LPS) for 24 h to investigate the role of miR-489-3p in IDD in an in vitro model. Reverse transcription-quantitative (RT-q)PCR was performed to determine the expression levels of miR-489-3p. Then, the TargetScan database was used to predict the potential binding sites between miR-489-3p and Toll-like receptor (TLR)4, and a dual-luciferase reporter assay was performed to verify the findings. Subsequently, RT-qPCR and western blotting were used to analyze the expression levels of TLR4. In addition, human nucleus pulposus (NP) cells were transfected with a miR-489-3p mimic and TLR4 overexpression plasmid to study the effects of miR-489-3p on LPS-induced human NP cells. Cell apoptosis and cell viability were also determined using flow cytometry and MTT assays, respectively. Finally, ELISAs were performed to analyze the levels of inflammatory factors. The expression levels of miR-489-3p were discovered to be downregulated in LPS-treated human NP cells. In addition, TLR4 was revealed to be a direct target gene of miR-489-3p, and its expression levels were upregulated in LPS-treated human NP cells. miR-489-3p was found to inhibit the LPS-induced decreases in cell viability and increases in apoptosis, and the concentration of inflammatory cytokines. Furthermore, miR-489-3p suppressed the LPS-induced decreases in extracellular matrix deposition via decreasing the expression levels of aggrecan and collagen type II in human NP cells. Finally, the results revealed that miR-489-3p inhibited the LPS-induced activation of the NF-κB signaling pathway in human NP cells. Conversely, all of the effects of miR-489-3p on LPS-induced human NP cells were reversed by the TLR4 overexpression plasmid. These findings suggested that miR-489-3p may represent a novel therapeutic target for the treatment of IDD.

A novel inactivated whole-cell Pseudomonas aeruginosa vaccine that acts through the cGAS-STING pathway

Pseudomonas aeruginosa infection continues to be a major threat to global public health, and new safe and efficacious vaccines are needed for prevention of infections caused by P. aeruginosa. X-ray irradiation has been used to prepare whole-cell inactivated vaccines against P. aeruginosa infection. However, the immunological mechanisms of X-ray-inactivated vaccines are still unclear and require further investigation. Our previous study found that an X-ray-inactivated whole-cell vaccine could provide protection against P. aeruginosa by boosting T cells. The aim of the present study was to further explore the immunological mechanisms of the vaccine. Herein, P. aeruginosa PAO1, a widely used laboratory strain, was utilized to prepare the vaccine, and we found nucleic acids and 8-hydroxyguanosine in the supernatant of X-ray-inactivated PAO1 (XPa). By detecting CD86, CD80, and MHCII expression, we found that XPa fostered dentritic cell (DC) maturation by detecting. XPa stimulated the cGAS-STING pathway as well as Toll-like receptors in DCs in vitro, and DC finally underwent apoptosis and pyroptosis after XPa stimulation. In addition, DC stimulated by XPa induced CD8⁺ T-cell proliferation in vitro and generated immunologic memory in vivo. Moreover, XPa vaccination induced both Th1 and Th2 cytokine responses in mice and reduced the level of inflammatory factors during infection. XPa protected mice in pneumonia models from infection with PAO1 or multidrug-resistant clinical isolate W9. Chronic obstructive pulmonary disease (COPD) mice immunized with XPa could resist PAO1 infection. Therefore, a new mechanism of an X-ray-inactivated whole-cell vaccine against P. aeruginosa infection was discovered in this study.

miR-138 inhibits epithelial-mesenchymal transition in silica-induced pulmonary fibrosis by regulating ZEB2

Silica dust is a common pollutant in the occupational environment, such as coal mines. Inhalation of silica dust can cause progressive pulmonary fibrosis and then silicosis. Silicosis is still one of the most harmful occupational diseases in the world, so the study of its pathogenesis is necessary for the treatment of silicosis. In this study, we constructed a mouse model of pulmonary fibrosis via intratracheal instillation of silica particles and identified the decreased expression of miR-138 in fibrotic lung tissues of mice. Moreover, the overexpression of miR-138 retarded the process of epithelial-mesenchymal transition (EMT) in a mouse model of silica particles exposure and epithelial cells stimulated by silica particles. Further studies showed that ZEB2 was one of the potential targets of miR-138, and the up-regulation of miR-138 reduced ZEB2 levels in mouse lung tissues and in epithelial cells. We next found that the expression levels of ɑ-SMA and Vimentin were significantly increased and E-cadherin levels were decreased after transfection with miR-138 inhibitor in epithelial cells. However, these effects were abated by the knockdown of ZEB2. Consistently, the increased migration ability of epithelial cells by miR-138 inhibitor transfection was also reversed by the knockdown of ZEB2. Collectively, we revealed that miR-138 significantly targeted ZEB2, thus inhibited the EMT process and mitigated the development of pulmonary fibrosis. miR-138 may be a potential target for the treatment of pulmonary fibrosis.

miR-770-5p inhibits the activation of pulmonary fibroblasts and silica-induced pulmonary fibrosis through targeting TGFBR1

Silicosis is a devastating interstitial lung disease arising from long-term exposure to inhalable silica. Regrettably, no therapy currently can effectively reverse the silica-induced fibrotic lesion. Emerging evidence has indicated that the dysregulation of microRNAs is involved in silica-induced pulmonary fibrosis. The aim of this study is to explore the expression pattern and underlying mechanisms of miR-770-5p in silica-induced pulmonary fibrosis. Consistent with our previous miRNA microarray analysis, the results of qRT-PCR showed that miR-770-5p expression was downregulated in silica-induced pulmonary fibrosis in humans and animal models. Administration of miR-770-5p agomir significantly reduced the fibrotic lesions in the lungs of mice exposed to silica dust. MiR-770-5p also exhibited a dramatic reduction in TGF-β1-activated human pulmonary fibroblasts (MRC-5). Transfection of miR-770-5p mimics significantly decreased the viability, migration ability, and S/G0 phase distribution, as well as the expression of fibronectin, collagen I, and α-SMA in TGF-β1-treated MRC-5 cells. Transforming growth factor-β receptor 1 (TGFBR1) was confirmed as a direct target of regulation by miR-770-5p. The expression of TGFBR1 was significantly increased in pulmonary fibrosis. Knockdown of TGFBR1 blocked the transduction of the TGF-β1 signaling pathway and attenuated the activation of MRC-5 cells, while overexpression of TGFBR1 effectively restored the activation of MRC-5 cells inhibited by miR-770-5p. Together, our results demonstrated that miR-770-5p exerted an anti-fibrotic effect in silica-induced pulmonary fibrosis by targeting TGFBR1. Targeting miR-770-5p might provide a new therapeutic strategy to prevent the abnormal activation of pulmonary fibroblasts in silicosis.

Long Noncoding RNA FENDRR Inhibits Lung Fibroblast Proliferation via a Reduction of β-Catenin

Idiopathic Pulmonary Fibrosis (IPF) is a chronic, progressive, and usually lethal lung disease and it has been widely accepted that fibroblast proliferation is one of the key characteristics of IPF. Long noncoding RNAs (lncRNAs) play vital roles in the pathogenesis of many diseases. In this study, we investigated the role of lncRNA FENDRR on fibroblast proliferation. Human lung fibroblasts stably overexpressing FENDRR showed a reduced cell proliferation compared to those expressing the control vector. On the other hand, FENDRR silencing increased fibroblast proliferation. FENDRR bound serine-arginine rich splicing factor 9 (SRSF9) and inhibited the phosphorylation of p70 ribosomal S6 kinase 1 (PS6K), a downstream protein of the mammalian target of rapamycin (mTOR) signaling. Silencing SRSF9 reduced fibroblast proliferation. FENDRR reduced β-catenin protein, but not mRNA levels. The reduction of β-catenin protein levels in lung fibroblasts by gene silencing or chemical inhibitor decreased fibroblast proliferation. Adenovirus-mediated FENDRR transfer to the lungs of mice reduced asbestos-induced fibrotic lesions and collagen deposition. RNA sequencing of lung tissues identified 7 cell proliferation-related genes that were up-regulated by asbestos but reversed by FENDRR. In conclusion, FENDRR inhibits fibroblast proliferation and functions as an anti-fibrotic lncRNA.

Dynamic assessing silica particle-induced pulmonary fibrosis and associated regulation of long non-coding RNA expression in Wistar rats

BACKGROUND

Exposure to respirable crystalline silica (RCS) can induce accelerated silicosis (AS), a form of silicosis that is more progressive and severe form of silicosis. In this project we aimed to assess processes of silicosis in rats exposed to RCS with focus on the regulation of long noncoding RNAs (lncRNAs).

RESULTS

The results showed that RCS induced acute inflammatory response as indicated by the appearance of inflammatory cells in the lung from the first day and peaked on day 7 of exposure. The fibroblasts appeared along with the inflammatory cells decreasing gradually on day 14. Extensive fibrosis appeared in the lung tissue, and silicon nodules were getting larger on day 28. Interestingly, the number of altered lncRNAs increased with the exposure time with 193, 424, 455, 421 and 682 lncRNAs on day 1, 7, 14, 21, and 28 after exposure, respectively. We obtained 285 lncRNAs with five significant temporal expression patterns whose expressions might correlate with severity of silicosis. KEGG analysis showed that lncRNAs from short time-series expression miner (STEM)-derived data mainly involved in 17 pathways such as complement and coagulation cascades.

CONCLUSIONS

The differential expression profiles of lncRNAs may be potential biomarkers in silicosis through modulating expressions of their relevant genes in lungs of rat and thus warrant further investigation.

MiRNA, a New Treatment Strategy for Pulmonary Fibrosis

Pulmonary fibrosis (PF) is the most common chronic, progressive interstitial lung disease, mainly occurring in the elderly, with a median survival of 2-4 years after diagnosis. Its high mortality rate attributes to the delay in diagnosis due to its generic symptoms, and more importantly, to the lack of effective treatments. MicroRNAs (miRNAs) are a class of small non-coding RNAs that are involved in many essential cellular processes, including extracellular matrix remodeling, alveolar epithelial cell apoptosis, epithelial-mesenchymal transition, etc. We summarized the dysregulated miRNAs in TGF-β signaling pathway-mediated PF in recent years with dual effects, such as anti-fibrotic let-7 family and pro-fibrotic miR-21 members. Therefore, this review will set out the latest application of miRNAs to provide a new direction for PF treatment.

The function of non-coding RNAs in idiopathic pulmonary fibrosis

Non-coding ribonucleic acids (ncRNAs) are a diverse group of RNA molecules that are mostly not translated into proteins after transcription, including long non-coding RNAs (lncRNAs) with longer than 200 nucleotides non-coding transcripts and microRNAs (miRNAs) which are only 18–22 nucleotides. As families of evolutionarily conserved ncRNAs, lncRNAs activate and repress genes via a variety of mechanisms at both transcriptional and translational levels, whereas miRNAs regulate protein-coding gene expression mainly through mRNA silencing. ncRNAs are widely involved in biological functions, such as proliferation, differentiation, migration, angiogenesis, and apoptosis. Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with a poor prognosis. The etiology of IPF is still unclear. Increasing evidence shows the close correlations between the development of IPF and aberrant expressions of ncRNAs than thought previously. In this study, we provide an overview of ncRNAs participated in pathobiology of IPF, seeking the early diagnosis biomarker and aiming for potential therapeutic applications for IPF.

LncRNA CHRF promotes TGF-β1 induced EMT in alveolar epithelial cells by inhibiting miR-146a up-regulating L1CAM expression

PURPOSE

Idiopathic pulmonary fibrosis (IPF) is a type of progressive lung fibrosis disease. The survival time of diagnosed IPF patients is often only 2 years. Currently much evidence showed that the epithelial-mesenchymal transition (EMT) process is the main cause of the occurrence and development of IPF. LncRNA cardiac hypertrophy related factor (CHRF) was reported to be related with IPF development. Here we explored the functions and regulatory mechanisms of CHRF on EMT in IPF.

MATERIALS AND METHODS

A549 cells were treated with transforming growth factor-β1 (TGF-β1) for 48 h to construct IPF cell model. CHRF and miR-146a expression were quantified using qPCR. The expression of L1 cell adhesion molecule (L1CAM) and EMT related indicators (E-cadherin, Vimentin, Slug and N-cadherin) were detected by qPCR and western blot. Dual luciferase reporter experiment was conducted to prove the molecular interaction of miR-146a and L1CAM, as well as CHRF and miR-146a.

RESULTS

CHRF and L1CAM expression were significantly upregulated and promoted the EMT process in A549 after treatment of TGF-β1. MiR-146a was obviously down-regulated, and knockdown of CHRF inhibited the EMT process by up-regulating miR-146a, in A549 after treatment of TGF-β1. Meanwhile, overexpression of miR-146a inhibited EMT process via targeting L1CAM. In addition, L1CAM overexpression eliminated the inhibitory effect of sh-CHRF on the EMT process.

CONCLUSIONS

These results provided evidence that CHRF promoted EMT process in A549 after treatment of TGF-β1, which proposed a new insight for depth understanding the pathological mechanisms of IPF.

Long non-coding RNAs: Promising new targets in pulmonary fibrosis

Pulmonary fibrosis is characterized by progressive and irreversible scarring in the lungs with poor prognosis and treatment. It is caused by various factors, including environmental and occupational exposures, and some rheumatic immune diseases. Even the rapid global spread of the COVID‐19 pandemic can also cause pulmonary fibrosis with a high probability. Functions attributed to long non‐coding RNAs (lncRNAs) make them highly attractive diagnostic and therapeutic targets in fibroproliferative diseases. Therefore, an understanding of the specific mechanisms by which lncRNAs regulate pulmonary fibrotic pathogenesis is urgently needed to identify new possibilities for therapy. In this review, we focus on the molecular mechanisms and implications of lncRNAs targeted protein‐coding and non‐coding genes during pulmonary fibrogenesis, and systematically analyze the communication of lncRNAs with various types of RNAs, including microRNA, circular RNA and mRNA. Finally, we propose the potential approach of lncRNA‐based diagnosis and therapy for pulmonary fibrosis. We hope that understanding these interactions between protein‐coding and non‐coding genes will contribute to the development of lncRNA‐based clinical applications for pulmonary fibrosis.

Long non‑coding RNA NEAT1 promotes pulmonary fibrosis by regulating the microRNA‑455‑3p/SMAD3 axis

Pulmonary fibrosis is an excessive repair response to tissue damage, triggering hyperplasia of fibrotic connective tissues; however, there is no effective treatment in a clinical setting. The purpose of the present study was to investigate the roles of long non-coding RNA nuclear enriched abundant transcript 1 (NEAT1) and microRNA-455-3p (miR-455-3p) were investigated in pulmonary fibrosis. In this study, the mRNA expression levels of NEAT1, miR-455-3p and SMAD3 in the HPAEpiC alveolar and BEAS-2B bronchial epithelial cell lines were determined using reverse transcription-quantitative PCR, while the markers of epithelial-mesenchymal transformation (EMT) and collagen production were determined using western blot analysis. A wound healing assay was performed to evaluate the migratory ability of the HPAEpiC and BEAS-2B cell lines. The interactions between NEAT1 and miR-455-3p or SMAD3 and miR-455-3p were validated using a luciferase reporter gene assay. The results showed that the mRNA expression levels of NEAT1 and SMAD3 were upregulated in the TGF-β1-treated HPAEpiC and BEAS-2B cell lines, while the mRNA expression level of miR-455-3p was significantly decreased. In addition, silencing NEAT1 effectively alleviated the migratory ability, EMT and collagen generation of the epithelial cells. Following these experiments, NEAT1 was identified as a sponge for miR-455-3p, and SMAD3 was a target gene of miR-455-3p. NEAT1 downregulation or miR-455-3p mimic inhibited the migratory ability, EMT and collagen production of the epithelial cells; however, the effects were reversed by the overexpression of SMAD3. Furthermore, NEAT1 knockdown reduced the expression level of SMAD3 by increasing the expression level of miR-455-3p to further inhibit the migratory ability, EMT and collagen production of epithelial cells.

Pivotal Role of TGF-β/Smad Signaling in Cardiac Fibrosis: Non-coding RNAs as Effectual Players

Unintended cardiac fibroblast proliferation in many pathophysiological heart conditions, known as cardiac fibrosis, results in pooling of extracellular matrix (ECM) proteins in the heart muscle. Transforming growth factor β (TGF-β) as a pivotal cytokine/growth factor stimulates fibroblasts and hastens ECM production in injured tissues. The TGF-β receptor is a heterodimeric receptor complex on the plasma membrane, made up from TGF-β type I, as well as type II receptors, giving rise to Smad2 and Smad3 transcription factors phosphorylation upon canonical signaling. Phosphorylated Smad2, Smad3, and cytoplasmic Smad4 intercommunicate to transfer the signal to the nucleus, culminating in provoked gene transcription. Additionally, TGF-β receptor complex activation starts up non-canonical signaling that lead to the mitogen-stimulated protein kinase cascade activation, inducing p38, JNK1/2 (c-Jun NH2-terminal kinase 1/2), and ERK1/2 (extracellular signal–regulated kinase 1/2) signaling. TGF-β not only activates fibroblasts and stimulates them to differentiate into myofibroblasts, which produce ECM proteins, but also promotes fibroblast proliferation. Non-coding RNAs (ncRNAs) are important regulators of numerous pathways along with cellular procedures. MicroRNAs and circular long ncRNAs, combined with long ncRNAs, are capable of affecting TGF-β/Smad signaling, leading to cardiac fibrosis. More comprehensive knowledge based on these processes may bring about new diagnostic and therapeutic approaches for different cardiac disorders.

Non-coding RNAs modulate function of extracellular matrix proteins

The extracellular matrix (ECM) creates a multifaceted system for the interaction of diverse structural proteins, matricellular molecules, proteoglycans, hyaluronan, and various glycoproteins that collaborate and bind with each other to produce a bioactive polymer. Alterations in the composition and configuration of ECM elements influence the cellular phenotype, thus participating in the pathogenesis of several human disorders. Recent studies indicate the crucial roles of non-coding RNAs in the modulation of ECM. Several miRNAs such as miR-21, miR-26, miR-19, miR-140, miR-29, miR-30, miR-133 have been dysregulated in disorders that are associated with disruption or breakdown of the ECM. Moreover, expression of MALAT1, PVT1, SRA1, n379519, RMRP, PFL, TUG1, TM1P3, FAS-AS1, PART1, XIST, and expression of other lncRNAs is altered in disorders associated with the modification of ECM components. In the current review, we discuss the role of lncRNAs and miRNAs in the modification of ECM and their relevance with the pathophysiology of human disorders such as cardiac/ lung fibrosis, cardiomyopathy, heart failure, asthma, osteoarthritis, and cancers.

Investigation of MicroRNA and transcription factor mediated regulatory network for silicosis using systems biology approach

Silicosis is a major health issue among workers exposed to crystalline silica. Genetic susceptibility has been implicated in silicosis. The present research demonstrates key regulatory targets and propagated network of gene/miRNA/transcription factor (TF) with interactions responsible for silicosis by integrating publicly available microarray data using a systems biology approach. Array quality is assessed with the Quality Metrics package of Bioconductor, limma package, and the network is constructed using Cytoscape. We observed and enlist 235 differentially expressed genes (DEGs) having up-regulation expression (85 nos) and down-regulation expression (150 nos.) in silicosis; and 24 TFs for the regulation of these DEGs entangled with thousands of miRNAs. Functional enrichment analysis of the DEGs enlighten that, the maximum number of DEGs are responsible for biological process viz, Rab proteins signal transduction (11 nos.) and Cellular Senescence (20 nos.), whereas IL-17 signaling pathway (16 nos.) and Signalling by Nuclear Receptors (14 nos.) etc. are Biological Pathway involving more DEGs. From the identified 1100 high target microRNA (miRNA)s involved in silicosis, 1055 miRNAs are found to relate with down-regulated genes and 847 miRNAs with up-regulated genes. The CDK19 gene (Up-regulated) is associated with 617 miRNAs whereas down-regulated gene ARID5B is regulated by as high as 747 high target miRNAs. In Prediction of Small-molecule signatures, maximum scoring small-molecule combinations for the DEGs have shown that CGP-60774 (with 20 combinations), alvocidib (with 15 combinations) and with AZD-7762 (24 combinations) with few other drugs having the high probability of success.

Dexamethasone can attenuate the pulmonary inflammatory response via regulation of the lncH19/miR-324-3p cascade

Objective

To investigate lncRNAs and their roles in regulating the pulmonary inflammatory response under dexamethasone (Dex) treatment.

Methods

IL-1β (10 ng/mL) and LPS (1 μg/mL) was used to construct inflammatory cell models with A549 cells; IL-1β performed better against LPS. Different concentrations of Dex were used to attenuate the inflammation induced by IL-1β, and its effect was assessed via RT-PCR to detect inflammatory cytokine-related mRNA levels, including those of IKβ-α, IKKβ, IL-6, IL-8, and TNF-α. Furthermore, ELISA was used to detect the levels of the inflammatory cytokines TNF-α, IL-6, and IL-8. RT-PCR was used to quantify the levels of lncRNAs, including lncMALAT1, lncHotair, lncH19, and lncNeat1. LncH19 was most closely associated with the inflammatory response, which was induced by IL-1β and attenuated by Dex. Among the lncRNAs, the level of lncH19 showed the highest increase following treatment with 1 and 10 μM Dex. Therefore, lncH19 was selected for further functional studies. LncH19 expression was inhibited by shRNA transduced with lentivirus. Cell assays for cell proliferation and apoptosis as well as RT-PCR, western blot, and ELISA for inflammatory genes were conducted to confirm the functions of lncH19. The predicted target miRNAs of lncH19 were hsa-miR-346, hsa-miR-324-3p, hsa-miR-18a-3p, hsa-miR-18b-5p, hsa-miR-146b-3p, hsa-miR-19b-3p, and hsa-miR-19a-3p. Following estimation via RT-PCR, hsa-miR-346, hsa-miR-18a-3p, and hsa-miR-324-3p showed consistent patterns in A549 NC and A549 shlncH19. An miRNA inhibitor was transfected into A549 NC and A549 shlncH19 cells, and the expression levels were determined via RT-PCR. hsa-miR-324-3p was inhibited the most compared with hsa-miR-346 and hsa-miR-18a-3p and was subjected to further functional studies. RT-PCR, ELISA, and western blotting for inflammatory gene detection were conducted to validate the functions of the target hsa-miR-324-3p.

Results

Treatment with 1 and 10 μM Dex could effectively attenuate the inflammatory response. During this process, lncH19 expression significantly increased (P < 0.05). Therefore, treatment with 1 μM Dex was used for further study. Under IL-1β treatment with or without Dex, lncH19 inhibition led to an increase in cell proliferation; a decrease in cell apoptosis; an increase in the protein levels of inflammatory genes; phosphorylation of P65, ICAM-1, and VCAM-1; and increase inflammatory cytokines. Prediction of the targets of lncH19 and validation via RT-PCR revealed that miR-346, miR-18a-3p, and miR-324-3p negatively correlate with lncH19. Additionally, Dex increased the lncH19 expression but reduced that of the miRNAs. Among the miRNAs, miR-324-3p was the most markedly downregulated miRNA following treatment of miRNA inhibitors. The MTS assay and cell apoptosis assay showed that the miR-324-3p inhibitor inhibited cell proliferation and induced cell apoptosis, thereby significantly attenuating the inflammatory response, which reversed the effect of lncH19 in regulating cell proliferation and the secretion of inflammatory cytokines (P < 0.05). Therefore, lncH19 might regulate miR-324-3p in pulmonary inflammatory response under Dex treatment.

Conclusion

Dex can attenuate the pulmonary inflammatory response by regulating the lncH19/miR-324-3p cascade.

MicroRNA-489-3p Represses Hepatic Stellate Cells Activation by Negatively Regulating the JAG1/Notch3 Signaling Pathway

BACKGROUND

The transformation of hepatic stellate cells (HSCs) into collagen-producing myofibroblasts is a key event in hepatic fibrogenesis. Recent studies have shown that microRNAs (miRNAs) play a critical role in the transformation of HSCs. However, the function of miR-489-3p in liver fibrosis remains unclear.

METHODS

Here, we detected the levels of miR-489-3p and jagged canonical Notch ligand 1 (JAG1) in liver fibrosis by using CCl4-treated rats as an in vivo model and transforming growth factor-beta 1 (TGF-β1)-treated HSC cell lines LX-2 and HSC-T6 as in vitro models. The expression of profibrotic markers was affected by transfecting LX-2 cells with either miR-489-3p mimic or si-JAG1. A dual-luciferase reporter assay was carried out to study the interaction of JAG1 with miR-489-3p.

RESULTS

We found that miR-489-3p was remarkably decreased while JAG1 was increased in liver fibrosis models both in vivo and in vitro. Overexpression of miR-489-3p reduced the expression of profibrotic markers and the activation of LX-2 cells induced by TGF-β1. Moreover, miR-489-3p decreased the expression of jagged canonical Notch ligand 1 (JAG1) in LX-2 cells by interacting with its 3'-UTR. As JAG1 is a Notch ligand, decreased JAG1 by miR-489-3p inhibited the Notch signaling pathway. Moreover, the downregulation of JAG1 inhibited the expression of fibrotic markers.

CONCLUSION

Our results indicate that miR-489-3p can inhibit HSC activation by inhibiting the JAG1/Notch3 signaling pathway.

Changing Expression Profiles of Messenger RNA, MicroRNA, Long Non-coding RNA, and Circular RNA Reveal the Key Regulators and Interaction Networks of Competing Endogenous RNA in Pulmonary Fibrosis

Pulmonary fibrosis is a kind of interstitial lung disease with architectural remodeling of tissues and excessive matrix deposition. Apart from messenger RNA (mRNA), microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA) could also play important roles in the regulatory processes of occurrence and progression of pulmonary fibrosis. In the present study, the pulmonary fibrosis model was administered with bleomycin. Whole transcriptome sequencing analysis was applied to investigate the expression profiles of mRNAs, lncRNAs, circRNAs, and miRNAs. After comparing bleomycin-induced pulmonary fibrosis model lung samples and controls, 286 lncRNAs, 192 mRNAs, 605 circRNAs, and 32 miRNAs were found to be differentially expressed. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to investigate the potential functions of these differentially expressed (DE) mRNAs and non-coding RNAs (ncRNAs). The terms related to inflammatory response and tumor necrosis factor (TNF) signaling pathway were enriched, implying potential roles in regulatory process. In addition, two co-expression networks were also constructed to understand the internal regulating relationships of these mRNAs and ncRNAs. Our study provides a systematic perspective on the potential functions of these DE mRNAs and ncRNAs during PF process and could help pave the way for effective therapeutics for this devastating and complex disease.

MiR-503 suppresses fibroblast activation and myofibroblast differentiation by targeting VEGFA and FGFR1 in silica-induced pulmonary fibrosis

Inhalation and deposition of crystalline silica particles in the lung can cause pulmonary fibrosis, then leading to silicosis. Given the paucity of effective drugs for silicosis, new insights for understanding the mechanisms of silicosis, including lung fibroblast activation and myofibroblast differentiation, are essential to explore therapeutic strategies. Our previous research showed that the up-regulation of miR-503 alleviated silica-induced pulmonary fibrosis in mice. In this study, we investigated whether miR-503 can regulate the TGF-β1-induced effects in lung fibroblasts. Mimic-based strategies aiming at up-regulating miR-503 were used to discuss the function of miR-503 in vivo and in vitro. We found that the expression level of miR-503 was decreased in fibroblasts stimulated by TGF-β1, and the up-regulation of miR-503 reduced the release of fibrotic factors and inhibited the migration and invasion abilities of fibroblasts. Combined with the up-regulation of miR-503 in a mouse model of silica-induced pulmonary fibrosis, we revealed that miR-503 mitigated the TGF-β1-induced effects in fibroblasts by regulating VEGFA and FGFR1 and then affecting the MAPK/ERK signalling pathway. In conclusion, miR-503 exerted protective roles in silica-induced pulmonary fibrosis and may represent a novel and potent candidate for therapeutic strategies in silicosis.

Harnessing noncoding RNA-based macrophage polarization: Emerging therapeutic opportunities for fibrosis

Aim

Organ fibrosis is a common pathological outcome of persistent tissue injury correlated with organ failure and death. Although current antifibrotic therapies have led to unprecedented successes, only a minority of patients with fibrosis benefit from these treatments. There is an urgent need to identify new targets and biomarkers that could be exploited in the diagnosis and treatment of fibrosis.

Methods

Macrophages play a dual role in the fibrogenesis across different organs either by promoting pro‐inflammatory or anti‐inflammatory responses. Noncoding RNAs (ncRNAs) have been demonstrated to play key roles in macrophage functions by manipulating macrophage polarization. Therefore, understanding the mechanism of ncRNA‐associated macrophage polarization is important to move toward therapeutic interventions.

Results

In this review, we provide an overview of recent insights into the role of ncRNAs in different fibrotic diseases by modulating macrophage phenotypic plasticity and functional heterogeneity. We also discuss the potential mechanisms of different ncRNAs integrate heterogeneous macrophages in fibrogenesis,including regulatory signatures, networks, and reciprocal interactions.

Conclusions

A broader understanding of how ncRNA‐directed macrophage phenotype transition in immunity and fibrosis might promote the development of a novel strategy for antifibrotic treatment.

Dexmedetomidine suppresses bupivacaine-induced parthanatos in human SH-SY5Y cells via the miR-7-5p/PARP1 axis-mediated ROS

This study aims to explore the regulatory mechanisms of dexmedetomidine in parthanatos. MTT assay was applied to reveal cell viability; JC-1 staining assay was utilized to reveal mitochondrial membrane potential. Reactive oxygen species (ROS) probe, DCFH-DA, was used to detect intracellular ROS production. Luciferase activity assay was applied to measure the binding between miR-7-5p and PARP1. We first identified that bupivacaine inhibited the viability and induced the parthanatos of human neuroblastoma SH-SY5Y cells. In addition, dexmedetomidine, a potent α2-adrenoceptor agonist, reversed the regulatory effect of bupivacaine on parthanatos of SH-SY5Y. More importantly, dexmedetomidine counteracted bupivacaine-induced changes of mitochondrial membrane potential and ROS production in SH-SY5Y cells. Hyper-activation of PARP1 plays a vital role in parthanatos. Further exploration of our study identified that bupivacaine triggered overexpression of PARP1 in SH-SY5Y cells. Bioinformatics analysis revealed that miR-7-5p targeted the 3' untranslated region (3' UTR) of PARP1 to inhibit PARP1 expression. In addition, dexmedetomidine recovered the suppressive effects of bupivacaine on miR-7-5p expression. Dexmedetomidine suppressed bupivacaine-induced parthanatos in SH-SY5Y cells via the miR-7-5p/PARP1 axis, which may shed a new insight into parthanatos-dependent neuronal injury.

miR-34a-5p Attenuates EMT through targeting SMAD4 in silica-induced pulmonary fibrosis

Silicosis is an incurable occupational disease, and its pathological feature is diffuse pulmonary fibrosis. Pulmonary epithelial-mesenchymal transition (EMT) is one of the important events in the pathogenesis of silicosis. Previous studies found that abnormal expression of various microRNAs (miRNAs) involved in the development of lung fibrosis. However, their roles in silicosis have not been elucidated. To research the biological effects of miR-34a in EMT process in silica-induced lung fibrosis, we established the silicosis model in mouse and miR-34a intervention in a cell model of TGF-β1 stimulated lung epithelial cells (A549). The results showed that miR-34a expression was down-regulated in the fibrotic lung tissue after silica treatment, and it was similarly expressed in A549 cells stimulated by TGF-β1. Meanwhile, silica-induced EMT process can increase expression of two mesenchymal markers, α-SMA and vimentin. Furthermore, overexpression miR-34a markedly inhibited EMT stimulated by TGF-β1. Mechanistically, SMAD4 was identified as the target of miR-34a. SMAD4 levels decreased in mRNA and protein levels in A549 cells upon miR-34a overexpression. In addition, the knockdown of SMAD4 blocked the EMT process. Taken together, miR-34a regulated EMT, which might be partially realized by targeting SMAD4. Our data might provide new insight into treatment targets for silica-induced pulmonary fibrosis.

lncRNA ZFAS1 promotes lung fibroblast-to-myofibroblast transition and ferroptosis via functioning as a ceRNA through miR-150-5p/SLC38A1 axis

Pulmonary fibrosis (PF) is a lethal fibrotic lung disease. The role of lncRNAs in multiple diseases has been confirmed, but the role and mechanism of lncRNA zinc finger antisense 1 (ZFAS1) in the progression of PF need to be elucidated further. Here, we found that lncRNA ZFAS1 was upregulated in bleomycin (BLM)-induced PF rats lung tissues and transforming growth factor-β1 (TGF-β1)-treated HFL1 cells, and positively correlated with the expression of solute carrier family 38 member 1 (SLC38A1), which is an important regulator of lipid peroxidation. Moreover, knockdown of lncRNA ZFAS1 significantly alleviated TGF-β1-induced fibroblast activation, inflammation and lipid peroxidation. In vivo experiments showed that inhibition of lncRNA ZFAS1 abolished BLM-induced lipid peroxidation and PF development. Mechanistically, silencing of lncRNA ZFAS1 attenuated ferroptosis and PF progression by lncRNA ZFAS1 acting as a competing endogenous RNA (ceRNA) and sponging miR-150-5p to downregulate SLC38A1 expression. Collectively, our studies demonstrated the role of the lncRNA ZFAS1/miR-150-5p/SLC38A1 axis in the progression of PF, and may provide a new biomarker for the treatment of PF patients.

miRNAs in Lung Development and Diseases

The development of the lung involves a diverse group of molecules that regulate cellular processes, organ formation, and maturation. The various stages of lung development are marked by accumulation of small RNAs that promote or repress underlying mechanisms, depending on the physiological environment in utero and postnatally. To some extent, the pathogenesis of various lung diseases is regulated by small RNAs. In this review, we discussed miRNAs regulation of lung development and diseases, that is, COPD, asthma, pulmonary fibrosis, and pulmonary arterial hypertension, and also highlighted possible connotations for human lung health.

TGF‑β1 induces CREB1‑mediated miR‑1290 upregulation to antagonize lung fibrosis via Napsin A

The pathologic mechanisms of pulmonary fibrosis (PF), one of the most common chronic pulmonary diseases, remain unclear. Napsin A is an aspartic proteinase that has been regarded as a hallmark of pulmonary adenocarcinoma. The present study aimed to investigate the specific function and molecular mechanisms of Napsin A in PF from the perspective of microRNA (miRNA or miR) regulation. In the present study, it was found that miR-1290 downregulated the expression of Napsin A by binding to its 3′-UTR. Cell viability was examined by MTT assay. The protein levels of α-smooth muscle actin (α-SMA), Collagen I and Napsin A were examined by western blot analysis. The predicted targeting of Napsin A by miR-1290 was validated by luciferase reporter assay. The protein content of α-SMA was examined by immunofluorescence staining. miR-1290 was found to be upregulated in blood samples from patients with PF and in TGF-β1-stimulated A549 cells. miR-1290 was found to directly target Napsin A. miR-1290 overexpression also significantly promoted A549 cell proliferation and increased the protein levels of markers of fibrosis. Napsin A knockdown exerted effects on A549 cell proliferation and TGF-β1-induced fibrosis that were similar to those induced by miR-1290 overexpression; more importantly, Napsin A knockdown significantly reversed the effects of miR-1290 inhibition, indicating that miR-1290 promotes TGF-β1-induced fibrosis by targeting Napsin A. Moreover, TGF-β1-induced CAMP responsive element binding protein 1 (CREB1) overexpression promoted the transcription of miR-1290 in A549 cells. On the whole, the findings of the present study demonstrate that TGF-β1-induced CREB1 over-expression induces the significant upregulation of miR-1290 expression, thus aggravating TGF-β1-induced fibrotic changes in A549 cells via the miR-1290 downstream target, Napsin A.

Differential expression of lncRNAs during silicosis and the role of LOC103691771 in myofibroblast differentiation induced by TGF-β1

OBJECTIVE

The role and molecular mechanism of long non-coding RNA (lncRNA)-related pathways in silicosis have not been elucidated clearly. The aims of this study were to evaluate the expression of lncRNAs during silica-induced pulmonary fibrosis and verify the function and molecular mechanism of LOC103691771 in myofibroblast differentiation induced by transforming growth factor-β1 (TGF-β1).

METHODS

RNA-sequencing was performed to assess differential expression of lncRNAs in control and silicotic rat lungs. Differential expression of lncRNAs was analyzed by Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes to identify their biological roles. LOC103691771, LOC102549714, LOC102550137, LOC103693125, and LOC103692016 were selected to verify their expression by real-time PCR of silicotic rat lung tissue and lung fibroblasts stimulated by TGF-β1. Specific small interfering RNA and an LOC103691771 overexpression plasmid were used to analyze the molecular mechanism in myofibroblast differentiation induced by TGF-β1.

RESULT

A total of 306 lncRNAs were expressed differentially in silicotic rat lungs, including 224 upregulated and 82 downregulated lncRNAs. The expression of LOC103691771, LOC102549714 and LOC102550137 was upregulated, while the expression of LOC103693125 and LOC103692016 was downregulated in silicotic rat lungs and TGF-β1-induced fibroblast, which was consistent with the results of RNA-sequencing. Furthermore, LOC103691771 gene silencing attenuated myofibroblast differentiation, whereas LOC103691771 overexpression promoted myofibroblast differentiation via regulation of the TGF-β1-Smad2/3 signaling pathway.

CONCLUSION

Our findings revealed that differential expression of lncRNAs was related to the development of silicosis, and LOC103691771 played a major role in myofibroblast differentiation induced by TGF-β1, which may serve as a potential therapeutic target for silicosis.

MiR-411-3p alleviates Silica-induced pulmonary fibrosis by regulating Smurf2/TGF-β signaling

Occupational exposure to silica dust particles was the major cause of pulmonary fibrosis, and many miRNAs have been demonstrated to regulate target mRNAs in silicosis. In the present study, we found that a decreasing level of miR-411-3p in silicosis rats and lung fibroblasts induced by TGF-β1. Enlargement of miR-411-3p could inhibit the cell proliferation and migration in lung fibroblasts with TGF-β1 treatment and attenuate lung fibrosis in silicotic mice. In addition, a mechanistic study showed that miR-411-3p exert its inhibitory effect on Smad ubiquitination regulatory factor 2 (Smurf2) expression and decrease ubiquitination degradation of Smad7 regulated by smurf2, result in blocking of TGF-β/Smad signaling. We proposed that increased expression of miR-411-3p abrogates silicosis by blocking activation of TGF-β/Smad signaling through decreasing ubiquitination degradation effect of smurf2 on Smad7.

MicroRNA-489 suppresses isoproterenol-induced cardiac fibrosis by downregulating histone deacetylase 2

Cardiac fibrosis is a hallmark of cardiovascular diseases. Several studies have indicated that microRNAs (miRs) are associated with the development of cardiac fibrosis. However, to date, the underlying molecular mechanisms of miR-489 in cardiac fibrosis have not been studied. The present study investigated the biological function of miR-489 in isoproterenol (ISO)-induced cardiac fibrosis. It was observed that miR-489 was downregulated in the heart tissue and cardiac fibroblasts (CFs) obtained from rats with ISO-induced cardiac fibrosis, as compared with the levels in the control group. By contrast, the expression levels of histone deacetylase 2 (HDAC2), collagen I (Col1A1) and α-smooth muscle actin (α-SMA) were increased in the heart tissue and CFs obtained from ISO-treated rats compared with the control group. Furthermore, ISO-treated CFs were transfected with a miR-489 mimic, which resulted in decreased viability and differentiation of CFs compared with the control group. Bioinformatics analysis and a dual-luciferase reporter assay further revealed that HDAC2 is a downstream target of miR-489. Subsequently, a loss-of-function experiment demonstrated that depletion of HDAC2 decreased the expression levels of Col1A1 and α-SMA in CFs. Taken together, the results obtained in the present study revealed that the miR-489/HDAC2 signaling pathway may serve as a novel regulatory mechanism in ISO-induced cardiac fibrosis and may increase the understanding on cardiac fibrosis.

Idiopathic Pulmonary Fibrosis: Pathogenesis and the Emerging Role of Long Non-Coding RNAs

Idiopathic pulmonary fibrosis (IPF) is a progressive chronic disease characterized by excessing scarring of the lungs leading to irreversible decline in lung function. The aetiology and pathogenesis of the disease are still unclear, although lung fibroblast and epithelial cell activation, as well as the secretion of fibrotic and inflammatory mediators, have been strongly associated with the development and progression of IPF. Significantly, long non-coding RNAs (lncRNAs) are emerging as modulators of multiple biological processes, although their function and mechanism of action in IPF is poorly understood. LncRNAs have been shown to be important regulators of several diseases and their aberrant expression has been linked to the pathophysiology of fibrosis including IPF. This review will provide an overview of this emerging role of lncRNAs in the development of IPF.

Suppression of long noncoding RNA NEAT1 attenuates hypoxia-induced cardiomyocytes injury by targeting miR-378a-3p

BACKGROUND/AIMS

lncRNA NEAT1 is involved in the development of many diseases. However, the function of lncRNA NEAT1 in myocardial infarction is unclear. Therefore, this experimental design based on lncRNA NEAT1 to explore the pathogenesis of myocardial infarction.

METHODS

RT-qPCR was used to detect the expression of lncRNA NEAT1 and miR-378a-3p in peripheral blood and mouse cardiomyocytes of patients with myocardial infarction. MTT assay, flow cytometry, Caspase-3 kit and transwell assay were used to detect the effects of lncRNA NEAT1 and miR-378a-3p on cardiomyocyte proliferation, apoptosis and migration. Target gene prediction and screening, luciferase reporter assays were used to verify downstream target genes for lncRNA NEAT1 and miR-378a-3p. Western blotting was used to detect the protein expression of Atg12 and related autophagy genes.

RESULTS

lncRNA NEAT1 was highly expressed in peripheral blood and mouse cardiomyocytes of patients with myocardial infarction. Moreover, lncRNA NEAT1 significantly promoted cell proliferation and migration of cardiomyocytes. In addition, lncRNA NEAT1 inhibited miR-378a-3p expression, and miR-378a-3p inhibited Atg12 expression, while lncRNA NEAT1 regulated expression of Atg12 and related autophagic factors via miR-378a-3p. Knockout of microRNA-378-3p reversed the effects of NEAT1 silencing on cell damage.

CONCLUSION

lncRNA NEAT1 can regulate the proliferation of cardiomyocytes by regulating miR-378-3p/Atg12 axis, thus accelerating the occurrence and development of cardiomyocytes.

lncRNA-Triggered Macrophage Inflammaging Deteriorates Age-Related Diseases

Aging and age-related diseases (ARDs) share basic mechanisms largely involving inflammation. A chronic, low-grade, subclinical inflammation called inflammaging occurs during aging. Autophagy defects, oxidative stresses, senescence-associated secretory phenotypes (SASPs), and DNA damage generally contribute to inflammaging and are largely regulated by numerous lncRNA through two-level vicious cycles disrupting cellular homeostasis: (1) inflammaging and the cellular senescence cascade and (2) autophagy defects, oxidative stress, and the SASP cascade. SASPs and inflammasomes simultaneously cause inflammaging. This review discusses the involvement of macrophage inflammaging in various ARDs and its regulation via lncRNA. Among macrophages, this phenomenon potentially impairs its immunosurveillance and phagocytosis mechanisms, leading to decreased recognition and clearance of malignant and senescent cells. Moreover, SASPs extracellularly manifest to induce paracrine senescence. Macrophage senescence escalates to organ level malfunction, and the organism is more prone to ARDs. By targeting genes and proteins or functioning as competing endogenous RNA (ceRNA), lncRNA regulates different phenomena including inflammaging and ARDs. The detailed mechanism warrants further elucidation to obtain pathological evidence of ARDs and potential treatment approaches.

Silencing circular RNA circANKRD36 remits lipopolysaccharide-induced inflammatory damage by regulating microRNA-15/MyD88

Bedsore is a familiar disease, which fearfully harms the health of the patients. We investigated the efficacy and mechanism of circular RNA circANKRD36 on HaCaT cell in inflammatory damage. CCK-8 and flow cytometry were respectively used to investigate the efficacies of lipopolysaccharide (LPS), circANKRD36, and microRNA (miR)-15 on cell viability and apoptosis. Moreover, circANKRD36 and miR-15 expression were changed by cell transfection and investigated by reverse transcription-quantitative polymerase chain reaction. Furthermore, the levels of Bax, pro caspase-3, cleaved caspase-3, interleukin (IL)-1β, IL-6, and proteins of the pathway were investigated by Western blot. Otherwise, the levels of IL-1β and IL-6 were investigated by enzyme-linked immunosorbent assay. Reactive oxygen species (ROS) was investigated by ROS assay. The relation between myeloid differentiation factor 88 (MyD88) and miR-15 was investigated by luciferase assay. LPS caused inflammatory damage and upregulated circANKRD36. circANKRD36 was silenced in cells and si-circANKRD36 remitted inflammatory damage. Furthermore, si-circANKRD36 negatively regulated miR-15 and miR-15 inhibitor could reverse the efficacies of si-circANKRD36. Besides, si-circANKRD36 restrained the NF-κB pathway by upregulating miR-15. Finally, MyD88 was authenticated as a target of miR-15. circANKRD36 remitted cell inflammatory damage upregulating miR-15/MyD88 via the NF-κB pathway in HaCaT cells.