LncRNA NEAT1 Promotes Inflammatory Response in Sepsis via the miR-31-5p/POU2F1 Axis

Circular RNA hsa_circ_0000175 Serves as a Potential Biomarker for Rheumatoid Arthritis via miR-31-5p/GSDME Axis

Rheumatoid arthritis (RA) is a common inflammatory autoimmune disease characterized by synovial inflammation and joint damage. Previous studies have shown that pyroptosis plays an important role in the pathogenesis of RA. In this study, the effects of circular RNA hsa_circ0000175 on pyroptosis and inflammation of RA were evaluated. Serum levels of circ_0000175 and miR-31-5p were determined by RT-qPCR, and the correlation between them was evaluated by Spearman correlation analysis. Fibroblast-like synoviocytes (FLSs) were extracted and prepared for in vitro study. The subcellular localization of circ_0000175 was detected by FISH assay. Pyroptosis and inflammatory cytokines interleukin (IL)-1β, IL-18 and IL-6 were measured by flow cytometry and ELISA, respectively. RNA pull-down and luciferase reporter assays verified the interaction between circ_0000175 and miR-31-5p. Western blot was used to detect the differential expression of pyroptosis-related factors (GSDME-N, GSDMD-N, cleaved caspase-1 and cleaved caspase-3). Circ_0000175 level was increased but miR-31-5p expression was decreased in PBMCs of RA patients and LPS/ATP-treated FLSs, companied with negative correlation. Moreover, miR-31-5p was a target of circ_0000175 in RA-FLSs. Silencing of circ_0000175 or overexpression of miR-31-5p significantly alleviated LPS/ATP-induced pyroptosis in FLSs through both caspase-1/GSDMD and caspase-3/GSDME pathways. Additionally, GSDME was identified as the target of miR-31-5p. The inhibitory effects of circ_0000175 depletion on pyroptosis and inflammation in RA-FLSs treated with LPS/ATP were strengthened by GSDME knockdown. Circ_0000175 can induce pyroptosis and trigger inflammatory response during the occurrence of RA through the miR-31-5p/GSDME axis, which provides a novel therapeutic target for RA treatment.

The role of lncRNA NEAT1 in human cancer chemoresistance

Chemotherapy is currently one of the most effective methods in clinical cancer treatment. However, chemotherapy resistance is an important reason for poor chemotherapy efficacy and prognosis, which has become an urgent problem to be solved in the field of cancer chemotherapy. Therefore, it is very important to deeply study and analyze the mechanism of cancer chemotherapy resistance and its regulatory factors. Long non-coding RNA nuclear paraspeckle assembly transcript 1 (LncRNA NEAT1) has been shown to be closely associated with chemotherapy resistance in cancer. NEAT1 induces cancer cell resistance to chemotherapeutic drugs by regulating cell apoptosis, cell cycle, drug transport and metabolism, DNA damage repair, EMT, autophagy, cancer stem cell characteristics, and metabolic reprogramming. This indicates that NEAT1 may be an important target to overcome chemotherapy resistance and is expected to be a potential biomarker to predict the effect of chemotherapy. This article summarizes the expression characteristics and clinical characteristics of NEAT1 in different cancers, and deeply discusses the regulatory role of NEAT1 in cancer chemotherapy resistance and related molecular mechanisms, aiming to clarify NEAT1 as a new target to overcome cancer chemotherapy resistance and the feasibility of chemotherapy sensitizers, with a view to providing a potential therapeutic direction for overcoming the dilemma of cancer resistance in the future.

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.

NEAT1 in inflammatory infectious diseases: An integrated perspective on molecular modulation

The long non-coding RNA (lncRNA), NEAT1, has emerged as a central figure in the intricate network of molecular regulators in inflammatory infectious diseases (IIDs). The review initiates a comprehensive exploration of NEAT1's multifaceted roles and molecular interactions in the context of these complex diseases. The study begins by acknowledging the global health burden of IIDs, underscoring the urgency for innovative insights into their pathogenesis and therapeutic avenues. NEAT1 is introduced as a pivotal lncRNA with growing relevance in immune responses and inflammatory processes. The core of this review unravels the NEAT1 landscape, elucidating its involvement in the modulation of immune signalling pathways, regulation of inflammatory cytokines, and interactions with various immune cells during infection. It explores NEAT1's role in orchestrating immune responses and balancing host defence mechanisms with the risk of immunopathology. Furthermore, the review underscores the clinical significance of NEAT1 in infectious diseases, discussing its associations with disease severity, prognosis, and potential as a diagnostic and therapeutic target. It provides insights into ongoing research endeavours aimed at harnessing NEAT1 for innovative disease management strategies, including developing RNA-based therapeutics. Concluding on a forward-looking note, the review highlights the broader implications of NEAT1 in the context of emerging infectious diseases and the possibility for precision medicine approaches that leverage NEAT1's regulatory capacities. In summary, this review illuminates the pivotal role of NEAT1 in IIDs by navigating its complex landscape, offering profound insights into its implications for disease pathogenesis and the development of targeted therapies.

Analysis of Immune and Prognostic-Related lncRNA PRKCQ-AS1 for Predicting Prognosis and Regulating Effect in Sepsis

Background

Sepsis was a high mortality and great harm systemic inflammatory response syndrome caused by infection. lncRNAs were potential prognostic marker and therapeutic target. Therefore, we expect to screen and analyze lncRNAs with potential prognostic markers in sepsis.

Methods

Transcriptome sequencing and limma was used to screen dysregulated RNAs. Key RNAs were screened by correlation analysis, lncRNA-mRNA co-expression and weighted gene co-expression network analysis. Immune infiltration, gene set enrichment analysis and gene set variation analysis were used to analyze the immune correlation. Kaplan-Meier curve, receiver operator characteristic curve, Cox regression analysis and nomogram were used to analyze the correlation between key RNAs and prognosis. Sepsis model was established by lipopolysaccharide-induced HUVECs injury, and then cell viability and migration ability were detected by cell counting kit-8 and wound healing assay. The levels of apoptosis-related proteins and inflammatory cytokines were detected by RT-qPCR and Western blot. Reactive Oxygen Species and superoxide dismutase were detected by commercial kit.

Results

Fourteen key differentially expressed lncRNAs and 663 key differentially expressed genes were obtained. And these lncRNAs were closely related to immune cells, especially T cell activation, immune response and inflammation. Subsequently, Subsequently, lncRNA PRKCQ-AS1 was identified as the regulator for further investigation in sepsis. RT-qPCR results showed that PRKCQ-AS1 expression was up-regulated in clinical samples and sepsis model cells, which was an independent prognostic factor in sepsis patients. Immune correlation analysis showed that PRKCQ-AS1 was involved in the immune response and inflammatory process of sepsis. Cell function tests confirmed that PRKCQ-AS1 could inhibit sepsis model cells viability and promote cell apoptosis, inflammatory damage and oxidative stress.

Conclusion

We constructed immune-related lncRNA-mRNA regulatory networks in the progression of sepsis and confirmed that PRKCQ-AS1 is an important prognostic factor affecting the progression of sepsis and is involved in immune response.

PE (0:0/14:0), an endogenous metabolite of the gut microbiota, exerts protective effects against sepsis-induced intestinal injury by modulating the AHR/CYP1A1 pathway

Sepsis is known to cause damage to the intestinal mucosa, leading to bacterial translocation, and exacerbation of both local and remote organ impairments. In the present study, fecal samples were collected from both septic and healthy individuals. Analysis through 16s rRNA sequencing of the fecal microbiota revealed that sepsis disrupts the balance of the gut microbial community. Recent research has highlighted the association of lipid metabolism with disease. By analyzing the fecal metabolome, four lipid metabolites that showed significant differences between the two groups were identified: PE (O-16:0/0:0), PE (17:0/0:0), PE (0:0/14:0), and PE (12:0/20:5 (5Z, 8Z, 11Z, 14Z, 17Z)). Notably, the serum levels of PE (0:0/14:0) were higher in the healthy group. Subsequent in vitro and in vivo experiments demonstrated the protective effects of this compound against sepsis-induced intestinal barrier damage. Label-free proteomic analysis showed significant differences in the expression levels of the aryl hydrocarbon receptor (AHR), a protein implicated in sepsis pathogenesis, between the LPS-Caco-2 and LPS-Caco-2 + PE (0:0/14:0) groups. Further analysis, with the help of Discovery Studio 3.5 software and co-immunoprecipitation assays, confirmed the direct interaction between AHR and PE (0:0/14:0). In the cecal ligation and puncture (CLP) model, treatment with PE (0:0 /14:0) was found to up-regulate the expression of tight junction proteins through the AHR/Cytochrome P450, family 1, subfamily A, and polypeptide 1 (CYP1A1) pathway. This highlights the potential therapeutic use of PE (0:0/14:0) in addressing sepsis-induced intestinal barrier damage.

Role of Macrophage lncRNAs in Mediating Inflammatory Processes in Atherosclerosis and Sepsis

Long noncoding RNAs (lncRNAs) are molecules >200 bases in length without protein-coding functions implicated in signal transduction and gene expression regulation via interaction with proteins or RNAs, exhibiting various functions. The expression of lncRNAs has been detected in many cell types, including macrophages, a type of immune cell involved in acute and chronic inflammation, removal of dead or damaged cells, and tissue repair. Increasing evidence indicates that lncRNAs play essential roles in macrophage functions and disease development. Additionally, many animal studies have reported that blockage or modulation of lncRNA functions alleviates disease severity or morbidity rate. The present review summarizes the current knowledge regarding lncRNAs expressed in macrophages, focusing on their molecular targets and the biological processes regulated by them during the development of inflammatory diseases such as atherosclerosis and sepsis. Possible application of this information to lncRNA-targeting therapy is also discussed. The studies regarding macrophage lncRNAs described in this review can help provide valuable information for developing treatments for various pathological conditions involving macrophages.

Exercise training attenuates angiotensin II-induced cardiac fibrosis by reducing POU2F1 expression

PURPOSE

Exercise training protects against heart failure. However, the mechanism underlying the protective effect of exercise training on angiotensin II (Ang II)-induced cardiac fibrosis remains unclear.

METHODS

An exercise model involving C57BL/6N mice and 6 weeks of treadmill training was used. Ang II (1.44 mg/kg/day) was administered to induce cardiac fibrosis. RNA sequencing and bioinformatic analysis were used to identify the key factors mediating the effects of exercise training on cardiac fibrosis. Primary adult mouse cardiac fibroblasts (CFs) were used in vitro. Adeno-associated virus serotype 9 was used to overexpress POU domain, class 2, transcription factor 1 (POU2F1) in vivo.

RESULTS

Exercise training attenuated Ang II-induced cardiac fibrosis and reversed 39 gene expression changes. The transcription factor regulating the largest number of these genes was POU2F1. Compared to controls, POU2F1 was shown to be significantly upregulated by Ang II, which is itself reduced by exercise training. In vivo, POU2F1 overexpression nullified the benefits of exercise training on cardiac fibrosis. In CFs, POU2F1 promoted cardiac fibrosis. CCAAT enhancer-binding protein β (C/EBPβ) was predicted to be the transcription factor of POU2F1 and verified using a dual-luciferase reporter assay. In vivo, exercise training activated AMP-activated protein kinase (AMPK) and alleviated the increase in C/EBPβ induced by Ang II. In CFs, AMPK agonist inhibited the increase in C/EBPβ and POU2F1 induced by Ang II, whereas AMPK inhibitor reversed this effect.

CONCLUSION

Exercise training attenuates Ang II-induced cardiac fibrosis by reducing POU2F1. Exercise training inhibits POU2F1 by activating AMPK, which is followed by the downregulation of C/EBPβ, the transcription factor of POU2F1.

The role of long noncoding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) in immune diseases

The long noncoding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) has been shown to be involved in the pathogenesis of several diseases. Herein, we discuss recent developments and insights into NEAT1 and its contribution to a variety of immune disorders. Our evaluations revealed that NEAT1's function in immune diseases seems to be focused on the modulation of paraspeckle expression and it is primarily associated with the nuclear retention of its mRNA. NEAT1 is also involved in the sequestration of paraspeckle proteins and in affecting the transcriptional expression of specific immune regulators. The expression of NEAT1 may be aberrantly upregulated in several immune pathologies, indicating that it could serve as a potential prognostic biomarker in these conditions. We summarized describing the expression changes and the role of NEAT1 in several immune diseases. We also described the mechanism of its regulation of the immune cell differentiation and function of NEAT1 in different disease.

circ-Katnal1 Enhances Inflammatory Pyroptosis in Sepsis-Induced Liver Injury through the miR-31-5p/GSDMD Axis

Background. Sepsis is a systemic inflammatory response that can elicit organ dysfunction as well as circulatory diseases in serious cases. When inflammatory responses are especially dysregulated, severe complications can arise, including sepsis-induced liver injury. Various microRNAs along with circular (circ) RNAs are involved in inflammatory responses; nevertheless, their functions in regulating sepsis-induced liver injury remain unknown. The cecal ligation and puncture (CLP) procedure can induce liver injury as well as polymicrobial sepsis. Methods. In this study, CLP was used to induce liver injury as well as polymicrobial sepsis. Then, liver function, inflammatory cytokine expression, and hepatic histopathology were evaluated. High-throughput sequencing was employed to investigate the abnormal hepatic circRNA expression after CLP. Raw264.7 cells were utilized to simulation an in vitro sepsis inflammation model with LPS induce. The relative mRNA as well as protein levels of TNF-α, IL-1β, and IL-6 was explored by quantitative polymerase chain reaction (PCR) and enzyme-linked immunosorbent assays. We explored functional connections among circRNAs, miR-31-5p, and gasdermin D (GSDMD) using dual-luciferase reporter assays. Western blot was employed to test GSDMD, caspase-1, and NLRP3 expression in mice and cell models. Results. Our results showed that CLP-induced sepsis promoted liver injury via increasing inflammatory pyroptosis. The abnormal expression of circ-Katnal1 played an important role in CLP-induced sepsis. Downregulating circ-Katnal1 suppressed LPS-induced inflammatory pyroptosis in Raw264.7 cells. Bioinformatics and luciferase reporter results confirmed that miR-31-5p and GSDMD were downstream targets of circ-Katnal1. Inhibiting miR-31-5p or upregulating GSDMD reversed the protective effects of silencing circ-Katnal1. Conclusion. Taken together, circ-Katnal1 enhanced inflammatory pyroptosis in sepsis-induced liver injury through the miR-31-5p/GSDMD axis.

Bioinspired copper single-atom nanozyme as a superoxide dismutase-like antioxidant for sepsis treatment

Sepsis is a systemic inflammatory response syndrome with high morbidity and mortality mediated by infection-caused oxidative stress. Early antioxidant intervention by removing excessively produced reactive oxygen and nitrogen species (RONS) is beneficial to the prevention and treatment of sepsis. However, traditional antioxidants have failed to improve patient outcomes due to insufficient activity and sustainability. Herein, by mimicking the electronic and structural characteristics of natural Cu-only superoxide dismutase (SOD5), a single-atom nanozyme (SAzyme) featuring coordinately unsaturated and atomically dispersed Cu-N4 site was synthesized for effective sepsis treatment. The de novo-designed Cu-SAzyme exhibits a superior SOD-like activity to efficiently eliminate O2 •-, which is the source of multiple RONS, thus blocking the free radical chain reaction and subsequent inflammatory response in the early stage of sepsis. Moreover, the Cu-SAzyme effectively harnessed systemic inflammation and multi-organ injuries in sepsis animal models. These findings indicate that the developed Cu-SAzyme possesses great potential as therapeutic nanomedicines for the treatment of sepsis.

Non-Coding RNA Networks as Potential Novel Biomarker and Therapeutic Target for Sepsis and Sepsis-Related Multi-Organ Failure

According to “Sepsis-3” consensus, sepsis is a life-threatening clinical syndrome caused by a dysregulated inflammatory host response to infection. A rapid identification of sepsis is mandatory, as the extent of the organ damage triggered by both the pathogen itself and the host’s immune response could abruptly evolve to multiple organ failure and ultimately lead to the death of the patient. The most commonly used therapeutic strategy is to provide hemodynamic and global support to the patient and to rapidly initiate broad-spectrum empiric antibiotic therapy. To date, there is no gold standard diagnostic test that can ascertain the diagnosis of sepsis. Therefore, once sepsis is suspected, the presence of organ dysfunction can be assessed using the Sepsis-related Organ Failure Assessment (SOFA) score, although the diagnosis continues to depend primarily on clinical judgment. Clinicians can now rely on several serum biomarkers for the diagnosis of sepsis (e.g., procalcitonin), and promising new biomarkers have been evaluated, e.g., presepsin and adrenomedullin, although their clinical relevance in the hospital setting is still under discussion. Non-codingRNA, including long non-codingRNAs (lncRNAs), circularRNAs (circRNAs) and microRNAs (miRNAs), take part in a complex chain of events playing a pivotal role in several important regulatory processes in humans. In this narrative review we summarize and then analyze the function of circRNAs-miRNA-mRNA networks as putative novel biomarkers and therapeutic targets for sepsis, focusing only on data collected in clinical settings in humans.

Construction of a lncRNA-associated competing endogenous RNA regulatory network after traumatic brain injury in mouse

Traumatic brain injury (TBI) is a major public health problem worldwide which causes high mortality and disability. Functioning as microRNA (miRNA) sponges, long non-coding RNA (lncRNA) regulates the expression of protein-coding genes in a competing endogenous RNA (ceRNA) network. However, the lncRNA-associated ceRNA in TBI remains unclear. In this study, we processed the raw SRR files of mice cortex samples of sham injury (n = 3) and TBI groups (n = 3) to count files. Then, the expression profiles of lncRNAs and mRNAs were identified, and 86 differentially expressed (DE) lncRNAs and 1201 DEmRNAs between sham and TBI groups were identified. The DEmRNAs were used to perform enrichment analyses. Next, a lncRNA-miRNA-mRNA regulatory ceRNA network was constructed. The network consisted of 23 mRNAs, 5 miRNAs and 2 lncRNAs. The expression alternations of the 5 miRNAs were validated via qRT-PCR. The subnetwork of hub lncRNA Neat1 was extracted. We identified a potential inflammatory associated regulatory axis: Neat1/miR-31-5p/Myd88 axis. The PPI network based on DEmRNA involved in ceRNA network was constructed PPI networks to identify the hub genes. Finally, DElncRNAs and DEmRNAs were selected randomly and validated by qRT-PCR. In conclusion, with the lncRNA-miRNA-mRNA ceRNA network provided above, we can improve our understanding of the regulatory mechanisms and interaction among lncRNAs, miRNAs and mRNAs in TBI process.

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.

Clinical Significance of the Serum lncRNA NORAD Expression in Patients with Neonatal Sepsis and Its Association with miR-410-3p

Purpose

Neonatal sepsis (NS) is one of the most crucial causes of death in newborns. This investigation aimed to validate the expression level of NORAD and the probable mechanism underlying the function of NORAD in NS.

Patients and Methods

The expression of NORAD and miR-410-3p was identified by qRT-PCR. The diagnostic sensitivity and specificity of NORAD were examined by the ROC curve. The NS cell models were established by the treatment of lipopolysaccharide (LPS) in the macrophage RAW264.7 cells. The luciferase report assay was performed to detect the target relationship between NORAD and miR-410-3p and the association between them was revealed by Pearson correlation.

Results

The expression of NORAD was at a higher level in the NS group than in the pneumonia controls. The levels of NORAD could sever as a diagnostic marker on discriminating NS patients from pneumonia neonates. The expression of IL-6, IL-8, and TNF-α was enhanced in the macrophage cells under LPS circumstances, while NORAD knockdown reversed the overexpression of these pro-inflammatory cytokines. Besides, miR-410-3p was a possible ceRNA of NORAD by the finding that the luciferase activity fell in the co-transfection of miR-410-3p mimics and WT-NORAD group. In vitro, LPS management could inhibit the expression of miR-410-3p, while silenced NORAD ameliorated the suppressed miR-410-3p levels. Decreased expression of miR-410-3p was discovered in NS patients and the changes of miR-410-3p expression were correlated with the levels of NORAD in the NS patients.

Conclusion

We found a raised level of NORAD in the NS patients and it might be a diagnostic indicator for NS patients. NORAD elimination meliorated the inflammation actions steered by LPS. MiR-410-3p was a target of NORAD and lowly expressed in the NS patients.

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.