LncRNA-AK149641 associated with airway inflammation in an OVA-induced asthma mouse model

A comprehensive review on the emerging role of long non-coding RNAs in the regulation of NF-κB signaling in inflammatory lung diseases

Public health globally faces significant risks from conditions like acute respiratory distress syndrome (ARDS), chronic obstructive pulmonary disease (COPD), and various inflammatory lung disorders. The NF-κB signaling system partially controls lung inflammation, immunological responses, and remodeling. Non-coding RNAs (lncRNAs) are crucial in regulating gene expression. They are increasingly recognized for their involvement in NF-κB signaling and the development of inflammatory lung diseases. Disruption of lncRNA-NF-κB interactions is a potential cause and resolution factor for inflammatory respiratory conditions. This study explores the therapeutic potential of targeting lncRNAs and NF-κB signaling to alleviate inflammation and restore lung function. Understanding the intricate relationship between lncRNAs and NF-κB signaling could offer novel insights into disease mechanisms and identify therapeutic targets. Regulation of lncRNAs and NF-κB signaling holds promise as an effective approach for managing inflammatory lung disorders. This review aims to comprehensively analyze the interaction between lncRNAs and the NF-κB signaling pathway in the context of inflammatory lung diseases. It investigates the functional roles of lncRNAs in modulating NF-κB activity and the resulting inflammatory responses in lung cells, focusing on molecular mechanisms involving upstream regulators, inhibitory proteins, and downstream effectors.

Long non coding RNAs reveal important pathways in childhood asthma: a future perspective

Asthma is a long-term inflammatory disease of the airways of the lungs refers changes that occur in conjunction with, or as a result of, chronic airway inflammation. Airway remodeling the subsequent of inflammation constitutes cellular and extracellular matrix changes in the wall airways, epithelial-to-mesenchymal-transition and airway smooth muscle cell proliferation. Diseases often begin in childhood and despite extensive research, causative pathogenic mechanisms still remain unclear. Transcriptome analysis of childhood asthma reveals distinct gene expression profiles of Long noncoding RNAs which have been reported to play a central regulatory role in various aspects of pathogenesis, clinical course and treatment of asthma. We briefly review current understanding of lnc-RNA dysregulation in children with asthma, focusing on their complex role in the inflammation, cell proliferation and remodeling of airway to guide future researches. We found that the lnc-RNAs increases activity of several oncogenes such c-Myc, Akt, and ERK and various signaling pathways such as MAPK (PI3K, Ras, JNK and p38), NF-κB and Wnt and crosstalk between these pathways by TGFβ, β-catenin, ERK and SKP2. Moreover, two different signal transduction pathways, Wnt and Notch1, can be activated by two lnc-RNAs through sponging the same miRNA for exacerbation cell proliferation.

CTRP3 regulates NF-κB and TGFβ1/Smad3 pathways to alleviate airway inflammation and remodeling in asthmatic mice induced by OVA

BACKGROUND

Asthma is a common illness with chronic airway inflammation. C1q/tumor necrosis factor (TNF)-related protein 3 (CTRP3) plays a vital role ininflammatory response, but its effect on asthma is imprecise. Herein, we analyzed the functions of CTRP3 in asthma.

METHODS

The BALB/c mice were randomized into four groups: control, ovalbumin (OVA), OVA+vector, and OVA+CTRP3. The asthmatic mice model was established by OVA stimulation. Overexpression of CTRP3 was implemented by the transfection of corresponding adeno-associated virus 6 (AAV6). The contents of CTRP3, E-cadherin, N-cadherin, smooth muscle alpha-actin (α-SMA), phosphorylated (p)-p65/p65, transforming growth factor-beta 1 (TGFβ1), and p-Smad3/Smad3 were determined by Western blot analysis. The quantity of total cells, eosinophils, neutrophils, and lymphocytes in bronchoalveolar lavage fluid (BALF) was assessed by using a hemocytometer. The contents of tumor necrosis factor-α and interleukin-1β in BALF were examined by enzyme-linked immunesorbent serologic assay. The lung function indicators and airway resistance (AWR) were measured. The bronchial and alveolar structures were evaluated by hematoxylin and eosin staining and sirius red staining.

RESULTS

The CTRP3 was downregulated in mice of OVA groups; however, AAV6-CTRP3 treatment markedly upregulated the expression of CTRP3. Upregulation of CTRP3 diminished asthmatic airway inflammation by decreasing the number of inflammatory cells and the contents of proinflammatory factors. CTRP3 markedly lessened AWR and improved lung function in OVA-stimulated mice. Histological analysis found that CTRP3 alleviated OVA-induced airway remodeling in mice. Moreover, CTRP3 modulated NF-κB and TGFβ1/Smad3 pathways in OVA-stimulated mice.

CONCLUSION

CTRP3 alleviated airway inflammation and remodeling in OVA-induced asthmatic mice via regulating NF-κB and TGFβ1/Smad3 pathways.

LncRNA-AK007111 affects airway inflammation in asthma via the regulation of mast cell function

Long noncoding RNAs (lncRNAs) are involved in gene transcription and pathophysiological processes of human diseases. Multiple lncRNAs have been shown to play important roles in the occurrence and development of asthma. This study aimed to explore the role of a novel lncRNA, lncRNA-AK007111, in asthma. Overexpression of lncRNA-AK007111 was induced in a mouse model of asthma via viral transfection, followed by the collection of alveolar lavage fluid and lung tissue for the detection of relevant inflammatory factors and pathological analysis of lung sections. Pulmonary resistance and respiratory dynamic compliance were measured using an animal pulmonary function analyzer. The number of mast cells sensitized by immunofluorescence was detected at the cellular level. The degree of degranulation of lncRNA-AK007111 after its knockdown was determined by detecting the level of β-hexosaminidase that was released and quantifying IL-6 and TNF-α using ELISA in a model of RBL-2H3 cells activated by immunoglobulin E plus antigen. Finally, we observed the migration ability of mast cells under a microscope. The results showed that in ovalbumin-sensitized mice, the upregulation of lncRNA-AK007111 promoted the infiltration of inflammatory cells in lung tissue, increased the number of total cells, eosinophils, and mast cells, upregulated IL-5 and IL-6 levels, and increased airway hyper-reactivity. Downregulation of lncRNA-AK007111 decreased the degranulation ability of IgE/Ag-activated mast cells and inhibited the expression of IL-6 and TNF-α; moreover, the migration ability of mast cells was significantly weakened. In conclusion, our study revealed that lncRNA-AK007111 plays an important role in asthma by modulating mast cell-related functions.

LINC1810064F22Rik sequesters miR-206-5p away from HDAC4 to exacerbate allergic airway inflammation and airway remodeling in an ovalbumin mouse model of asthma

Allergic inflammation and airway remodeling frequently occur in asthma. This study clarifies a novel LINC1810064F22Rik-mediated ceRNA mechanism involved in asthma-induced allergic inflammation and airway remodeling based on bioinformatics analysis and in vivo and in vitro experiments. The differentially expressed lncRNAs and downstream effectors were predicted in silico. The targeting relationship among LINC1810064F22Rik, miR-206-5p, and HDAC4 was predicted by bioinformatics analysis, which was further validated by dual luciferase reporter gene assay. The asthma-like airway inflammation was induced in mice using ovalbumin (OVA) sensitization/challenge with immune adjuvant Al(OH)₃, while alveolar epithelial cells (AECs) were exposed to IL-33 to mimic in vitro inflammatory environment. LINC1810064F22Rik and HDAC4 were highly expressed, while miR-206-5p was poorly expressed in the tracheal tissues of OVA mice and the IL-33-treated AECs. The OVA mice and IL-33-treated AECs were subjected to gain- or loss-of-function experiments to detect the interaction of LINC1810064F22Rik/miR-206-5p/HDAC4 axis and their effects on allergic inflammation and airway remodeling. LINC1810064F22Rik competitively bound to miR-206-5p, and miR-206-5p targeted and inhibited HDAC4. The in vivo animal experiments indicated that LINC1810064F22Rik promoted asthma-induced allergic inflammation and airway remodeling by sequestering miR-206-5p away from HDAC4. The evidence provided by our study highlighted the involvement of the LINC1810064F22Rik/miR-206-5p/HDAC4 axis in facilitating allergic airway inflammation and airway remodeling in OVA mice.

The protective effects of baicalin for respiratory diseases: an update and future perspectives

Background: Respiratory diseases are common and frequent diseases. Due to the high pathogenicity and side effects of respiratory diseases, the discovery of new strategies for drug treatment is a hot area of research. Scutellaria baicalensis Georgi (SBG) has been used as a medicinal herb in China for over 2000 years. Baicalin (BA) is a flavonoid active ingredient extracted from SBG that BA has been found to exert various pharmacological effects against respiratory diseases. However, there is no comprehensive review of the mechanism of the effects of BA in treating respiratory diseases. This review aims to summarize the current pharmacokinetics of BA, baicalin-loaded nano-delivery system, and its molecular mechanisms and therapeutical effects for treating respiratory diseases.

Method: This review reviewed databases such as PubMed, NCBI, and Web of Science from their inception to 13 December 2022, in which literature was related to “baicalin”, “Scutellaria baicalensis Georgi”, “COVID-19”, “acute lung injury”, “pulmonary arterial hypertension”, “asthma”, “chronic obstructive pulmonary disease”, “pulmonary fibrosis”, “lung cancer”, “pharmacokinetics”, “liposomes”, “nano-emulsions”, “micelles”, “phospholipid complexes”, “solid dispersions”, “inclusion complexes”, and other terms.

Result: The pharmacokinetics of BA involves mainly gastrointestinal hydrolysis, the enteroglycoside cycle, multiple metabolic pathways, and excretion in bile and urine. Due to the poor bioavailability and solubility of BA, liposomes, nano-emulsions, micelles, phospholipid complexes, solid dispersions, and inclusion complexes of BA have been developed to improve its bioavailability, lung targeting, and solubility. BA exerts potent effects mainly by mediating upstream oxidative stress, inflammation, apoptosis, and immune response pathways. It regulates are the NF-κB, PI3K/AKT, TGF-β/Smad, Nrf2/HO-1, and ERK/GSK3β pathways.

Conclusion: This review presents comprehensive information on BA about pharmacokinetics, baicalin-loaded nano-delivery system, and its therapeutic effects and potential pharmacological mechanisms in respiratory diseases. The available studies suggest that BA has excellent possible treatment of respiratory diseases and is worthy of further investigation and development.

Gene expression profiles and bioinformatics analysis in lung samples from ovalbumin-induced asthmatic mice

BACKGROUND

Asthma is characterized by chronic inflammation and airway remodeling. However, limited study is conducted on the gene expression profiles of ovalbumin (OVA) induced asthma in mice. Here, we explored the gene expression profiles in lung tissues from mice with OVA-induced asthma using microarray and bioinformatics analysis.

METHODS

For establishment of OVA-induced asthma model, mice first received intraperitoneal sensitization with OVA on day 0, 7 and 14, followed by atomizing inhalation of OVA 3 times a week for 8 weeks. The lung tissues were collected and subjected to microarray analysis, bioinformatics analysis and expression validation.

RESULTS

Microarray data of lung tissues suggested that 3754 lncRNAs and 2976 mRNAs were differentially expressed in lung tissues between control and asthmatic mice, including 1647 up-regulated and 2106 down-regulated lncRNAs, and 1201 up-regulated and 1766 down-regulated mRNAs. GO analysis displayed that the up-regulated genes were enriched in inflammatory response, leukocyte migration involved in inflammatory response, and Notch signaling pathway. KEGG pathway analysis indicated that the enriched pathway terms of the up-regulated gene included Toll-like receptor signaling pathway and Th17 cell differentiation signaling pathway. Additionally, based on the previously published literatures on asthma and inflammation, we screened out down-regulated genes, such as Smg7, Sumo2, and Stat5a, and up-regulated genes, such as Myl9, Fos and Tlr4. According to the mRNA-lncRNA co-expression network, we selected lncRNAs associated with above genes, including the down-regulated lncRNAs of NONMMUT032848, NONMMUT008873, NONMMUT009478, and NONMMUT006807, and the up-regulated lncRNAs of NONMMUT052633, NONMMUT05340 and NONMMUT042325. The expression changes of the above genes were validated in lung tissues by real-time quantitaive PCR and Western blot.

CONCLUSIONS

Overall, we performed gene microarray on lung samples from OVA-induced asthmatic mice and summarized core mRNAs and their related lncRNAs. This study may provide evidence for further research on the therapeutic targets of asthma.

Noncoding RNAs and Virus and Treatment in Allergic Rhinitis

Allergic rhinitis (AR) is a type I hypersensitivity reaction disease caused by inhaled allergens and immunoglobulin E (IgE)-mediated. Noncoding RNA (ncRNA) is an important regulator involved in gene expression and can be detected in the cytoplasm or extracellular fluid, which mainly includes microRNAs (miRNA, length 22-24 nucleotides), long noncoding RNAs (lncRNA, length >200 nucleotides), and circRNAs. LncRNA and miRNA both participate in the regulation of immune function. Some respiratory viral infections can aggravate allergic rhinitis, such as a respiratory syncytial virus (RSV) and human metapneumovirus (hMPV). However, the interaction between viral infection and allergy is complex and the mechanism is still unclear. In this review, we summarized the interactions of noncoding RNAs and viruses in the occurrence and development of AR, along with the treatments focusing on the noncoding RNAs in the past five years.

The Role of Noncoding RNA in Airway Allergic Diseases through Regulation of T Cell Subsets

Allergic rhinitis and asthma are common airway allergic diseases, the incidence of which has increased annually in recent years. The human body is frequently exposed to allergens and environmental irritants that trigger immune and inflammatory responses, resulting in altered gene expression. Mounting evidence suggested that epigenetic alterations were strongly associated with the progression and severity of allergic diseases. Noncoding RNAs (ncRNAs) are a class of transcribed RNA molecules that cannot be translated into polypeptides and consist of three major categories, microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs). Previous studies showed that ncRNAs were involved in the physiopathological mechanisms of airway allergic diseases and contributed to their occurrence and development. This article reviews the current state of understanding of the role of noncoding RNAs in airway allergic diseases, highlights the limitations of recent studies, and outlines the prospects for further research to facilitate the clinical translation of noncoding RNAs as therapeutic targets and biomarkers.

Eupatilin Suppresses OVA-Induced Asthma by Inhibiting NF-κB and MAPK and Activating Nrf2 Signaling Pathways in Mice

To investigate the effect of eupatilin in asthma treatment, we evaluated its therapeutic effect and related signal transduction in OVA-induced asthmatic mice and LPS-stimulated RAW264.7 cells. The BALF was tested for changes in lung inflammatory cells. Th2 cytokines in the BALF and OVA-IgE in the serum were measured by ELISA. H&E and PAS staining were used to evaluate histopathological changes in mouse lungs. The key proteins NF-κB, MAPK, and Nrf2 in lung tissues were quantitatively analyzed by Western blotting. Finally, we evaluated the effect of eupatilin on cytokines and related protein expression in LPS-stimulated RAW 264.7 cells in vitro. In OVA-induced asthmatic mice, eupatilin reduced the numbers of inflammatory cells, especially neutrophils and eosinophils. Eupatilin also decreased the levels of IL-5, IL-13 in the BALF and OVA-IgE in the serum. Furthermore, eupatilin inhibited the activation of NF-κB and MAPK pathways and increased the expression of Nrf2 in OVA-induced asthmatic mice. In vitro, eupatilin significantly reduced LPS-stimulated NO, IL-6, and ROS production. Additionally, the NF-κB, MAPK, and Nrf2 protein expression in LPS-stimulated RAW264.7 cells was consistent with that in OVA-induced asthmatic lung tissues. In summary, eupatilin attenuated OVA-induced asthma by regulating NF-κB, MAPK, and Nrf2 signaling pathways. These results suggest the utility of eupatilin as an anti-inflammatory drug for asthma treatment.

LncRNA RP5-857K21.7 inhibits PDGF-BB-induced proliferation and migration of airway smooth muscle cells through the miR-508-3p/PI3K/AKT/mTOR axis

The continuous increase in the prevalence of asthma poses a threat to human health. Despites numerous researches, the understanding of asthma development still remain elusive, hindering the development of effective treatment. Here, we explored the role of lncRNA RP5-857K21.7 (RP5-857K21.7) in the development of asthma and its potential molecular mechanism of regulation. Airway smooth muscle cells (ASMCs) were isolated and cultured after which some of the cells were induced with PDGF-BB to build an asthma cell model, and then, qRT-PCR analysis was used to measure the expression level of RP5-857K21.7 in the cell model. Result shows that the RP5-857K21.7 is significantly downregulated in PDGF-BB-induced ASMCs cells. Through CCK-8, transwell, and flow cytometry assay, we examined the functional impact of RP5-857K21.7 on the proliferation, migration, and apoptosis of the ASMCs, respectively, and found that the overexpression of RP5-857K21.7 markedly inhibit PDGF-BB-induced ASMCs cell proliferation, migration and induce apoptosis. Bioinformatics analysis predicted that the RP5-857K21.7 could sponge miR-508-3p and result was validated through a dual-luciferase reporter assay, biotinylated RNA pull-down assay, and RIP-qRT-PCR analysis. Mechanistically, RP5-857K21.7 regulates the PI3K/AKT/mTOR pathway by endogenously sponging miR-508-3p to inhibit PDGF-BB-induced ASMCs cell proliferation, migration and induce apoptosis. The current research suggests that the RP5-857K21.7 and its associated molecular pathway (miR-508-3p/PI3K/AKT/mTOR axis) might be a useful therapeutic target for the treatment of asthma disease.

Long non-coding RNA NKILA alleviates airway inflammation in asthmatic mice by promoting M2 macrophage polarization and inhibiting the NF-κB pathway

Asthma remains a severe public health problem. Long non-coding RNAs (lncRNAs) are potent regulators in various diseases including asthma. This study investigated the mechanism of lncRNA NF-κB interacting lncRNA (NKILA) in asthma. The model of asthma in mice was induced by ovalbum (OVA). LncRNA NKILA expression, serum total IgE level and expressions of inflammatory cytokines (IL-4, IL-5, IL-13, and TNF-α) in OVA-induced asthmatic mice were detected. NKILA was overexpressed to evaluate the airway inflammation and airway hyperresponsiveness (AHR) in asthmatic mice. Macrophage abundance, M1/M2-polarized macrophage numbers, and expressions of macrophage polarization-related genes were detected. Levels of the NF-κB pathway-related proteins were determined. Downregulated NKILA and upregulated total IgE level and expressions of inflammatory cytokines were observed in asthmatic mice. NKILA overexpression alleviated AHR and airway inflammation in asthmatic mice. NKILA reduced macrophage abundance and promoted M2 macrophage polarization in asthmatic mice. NKILA inhibited the NF-κB pathway in asthmatic mice. We highlighted that lncRNA NKILA limited the asthmatic airway inflammation via promoting M2 macrophage polarization and inhibiting the NF-κB pathway.