miR-20a-5p ameliorates ovalbumin (OVA)-induced mouse model of allergic asthma through targeting ATG7-regulated cell death, fibrosis and inflammation

Occupational agents-mediated asthma: From the perspective of autophagy

Occupational asthma (OA) is a common occupational pulmonary disease that is frequently underdiagnosed and underreported. The complexity of diagnosing and treating OA creates a significant social and economic burden, making it an important public health issue. In addition to avoiding allergens, patients with OA require pharmacotherapy; however, new therapeutic targets and strategies need further investigation. Autophagy may be a promising intervention target, but there is a lack of relevant studies summarizing the role of autophagy in OA. In this review consolidates the current understanding of OA, detailing principal and novel agents responsible for its onset. Additionally, we summarize the mechanisms of autophagy in HMW and LMW agents induced OA, revealing that occupational allergens can induce autophagy disorders in lung epithelial cells, smooth muscle cells, and dendritic cells, ultimately leading to OA through involving inflammatory responses, oxidative stress, and cell death. Finally, we discuss the prospects of targeting autophagy as an effective strategy for managing OA and even steroid-resistant asthma, encompassing autophagy interventions focused on organoids, organ-on-a-chip systems, nanomaterials vehicle, and nanobubbles; developing combined exposure models, and the role of non-classical autophagy in occupational asthma. In briefly, this review summarizes the role of autophagy in occupational asthma, offers a theoretical foundation for OA interventions based on autophagy, and identifies directions and challenges for future research.

Carvacrol inhibits the progression of oral submucous fibrosis via downregulation of PVT1/miR-20a-5p-mediated pyroptosis

Oral submucous fibrosis (OSF) is a precancerous condition in the oral cavity, which is closely related to the myofibroblast conversion of buccal mucosal fibroblasts (BMFs) after chronic consumption of areca nut. Emerging evidence suggests pyroptosis, a form of programmed cell death that is mediated by inflammasome, is implicated in persistent myofibroblast activation and fibrosis. Besides, numerous studies have demonstrated the effects of non-coding RNAs on pyroptosis and myofibroblast activities. Herein, we aimed to target key long non-coding RNA PVT1 with natural compound, carvacrol, to alleviate pyroptosis and myofibroblast activation in OSF. We first identified PVT1 was downregulated in the carvacrol-treated fBMFs and then demonstrated that myofibroblast features and expression of pyroptosis makers were all reduced in response to carvacrol treatment. Subsequently, we analysed the expression of PVT1 and found that PVT1 was aberrantly upregulated in OSF specimens and positively correlated with several fibrosis markers. After revealing the suppressive effects of carvacrol on myofibroblast characterisitcs and pyroptosis were mediated by repression of PVT1, we then explored the potential mechanisms. Our data showed that PVT1 may serve as a sponge of microRNA(miR)-20a to mitigate the myofibroblast activation and pyroptosis. Altogether, these findings indicated that the anti-fibrosis effects of carvacrol merit consideration and may be due to the attenuation of pyroptosis and myofibroblast activation by targeting the PVT1/miR-20a axis.

Insights on E1-like enzyme ATG7: functional regulation and relationships with aging-related diseases

Autophagy is a dynamic self-renovation biological process that maintains cell homeostasis and is responsible for the quality control of proteins, organelles, and energy metabolism. The E1-like ubiquitin-activating enzyme autophagy-related gene 7 (ATG7) is a critical factor that initiates classic autophagy reactions by promoting the formation and extension of autophagosome membranes. Recent studies have identified the key functions of ATG7 in regulating the cell cycle, apoptosis, and metabolism associated with the occurrence and development of multiple diseases. This review summarizes how ATG7 is precisely programmed by genetic, transcriptional, and epigenetic modifications in cells and the relationship between ATG7 and aging-related diseases.

DEK deficiency suppresses mitophagy to protect against house dust mite-induced asthma

DEK protein is highly expressed in asthma. However, the mechanism of DEK on mitophagy in asthma has not been fully understood. This study aims to investigate the role and mechanism of DEK in asthmatic airway inflammation and in regulating PINK1-Parkin-mediated mitophagy, NLRP3 inflammasome activation, and apoptosis. PINK1-Parkin mitophagy, NLRP3 inflammasome, and apoptosis were examined after gene silencing or treatment with specific inhibitors (MitoTEMPO, MCC950, and Ac-DEVD-CHO) in house dust mite (HDM) or recombinant DEK (rmDEK)-induced WT and DEK-/- asthmatic mice and BEAS-2B cells. The regulatory role of DEK on ATAD3A was detected using ChIP-sequence and co-immunoprecipitation. rmDEK promoted eosinophil recruitment, and co-localization of TOM20 and LC3B, MFN1 and mitochondria, LC3B and VDAC, and ROS generation, reduced protein level of MnSOD in HDM induced-asthmatic mice. Moreover, rmDEK also increased DRP1 expression, PINK1-Parkin-mediated mitophagy, NLRP3 inflammasome activation, and apoptosis. These effects were partially reversed in DEK-/- mice. In BEAS-2B cells, siDEK diminished the Parkin, LC3B, and DRP1 translocation to mitochondria, mtROS, TOM20, and mtDNA. ChIP-sequence analysis showed that DEK was enriched on the ATAD3A promoter and could positively regulate ATAD3A expression. Additionally, ATAD3A was highly expressed in HDM-induced asthma models and interacted with DRP1, and siATAD3A could down-regulate DRP1 and mtDNA-mediated mitochondrial oxidative damage. Conclusively, DEK deficiency alleviates airway inflammation in asthma by down-regulating PINK1-Parkin mitophagy, NLRP3 inflammasome activation, and apoptosis. The mechanism may be through the DEK/ATAD3A/DRP1 signaling axis. Our findings may provide new potential therapeutic targets for asthma treatment.

Evaluation of the Expression of miRNAs, LncRNAs, and their Target Gene, Caspase 3 in Glioblastoma Multiform: A Case-Control Study

Glioblastoma multiform (GBM) is an invasive cancer that causes high mortality in patients. Disruption of the apoptosis process is one of the main pathogenesis of the disease. Recently, LncRNAs and miRNAs have been shown to play an important role in the process of apoptosis. To follow the aim of study, 100 patients participated in the two groups of 50 individuals, including 50 GBM patients and 50 healthy individuals as the control group. Mononuclear cells were isolated from peripheral blood samples and RNA extraction was done. The expression changes of miR-17-5p, miR-20-5p, LINC01605, FAS-AS1, and Caspase 3 were examined using RT-PCR in both groups. Expression of LINC01605, miR-20-5p, and miR-17-5p increased in patients, while Caspase 3 and FAS-AS1 decreased; the difference was statistically significant between the two groups. In addition, it was found that these factors have the appropriate sensitivity and specificity as diagnostic markers. Finally, It is suggested to use the LINC01605, FAS-AS1, miR-20-5p, miR-17-5p, and Caspase 3 as apoptosis predictors in the GM patients.

Lactobacillus rhamnosus 76 alleviates airway inflammation in ovalbumin-allergic mice and improves mucus secretion by down-regulating STAT6/SPDEF pathway

Previous studies have reported a correlation between the dysregulation of intestinal microbiota and the occurrence of asthma. This study aimed to investigate the effect of probiotic Lactobacillus rhamnosus 76 (LR76) on ovalbumin (OVA)-allergic mice and the mechanism of LR76 affecting mucus secretion in asthma. OVA-allergic mice were supplemented with LR76, and 16HBE cells induced by interleukin-13 (IL-13) were treated with LR76 supernatant (LR76-s) to observe the effect of LR76. In OVA-sensitized mice, LR76 alleviated the inflammatory cell infiltration in lung tissue and reduced the inflammatory cell counts of BALF. The expression level of mRNA, including Il4, Il5, Il13, Il25, Tgfb1, Il10, and Ifng, was decreased in the lung tissue of mice in the LR76 group compared with the OVA group. MUC5AC expression was down-regulated, while SCGB1A1 was up-regulated in the lung tissue of OVA-allergic mice after being supplemented with LR76 and in 16HBE cells induced by IL-13 after incubating with LR76-s. LR76 and LR76-s down-regulated the expression of proteins, including STAT6, p-STAT6, and SPDEF, and mRNA of STAT6 and SPDEF. In conclusion, LR76 alleviated airway inflammation and Th2 response in OVA-allergic mice and improved the mucus secretion of mouse lung tissue and 16HBE cells in the asthma model by down-regulating STAT6/SPDEF pathway.

Programmed Cell Death in Asthma: Apoptosis, Autophagy, Pyroptosis, Ferroptosis, and Necroptosis

Bronchial asthma is a complex heterogeneous airway disease, which has emerged as a global health issue. A comprehensive understanding of the different molecular mechanisms of bronchial asthma may be an efficient means to improve its clinical efficacy in the future. Increasing research evidence indicates that some types of programmed cell death (PCD), including apoptosis, autophagy, pyroptosis, ferroptosis, and necroptosis, contributed to asthma pathogenesis, and may become new targets for future asthma treatment. This review briefly discusses the molecular mechanism and signaling pathway of these forms of PCD focuses on summarizing their roles in the pathogenesis and treatment strategies of asthma and offers some efficient means to improve clinical efficacy of therapeutics for asthma in the near future.

New insights into autophagy in inflammatory subtypes of asthma

Asthma is a heterogeneous airway disease characterized by airway inflammation and hyperresponsiveness. Autophagy is a self-degrading process that helps maintain cellular homeostasis. Dysregulation of autophagy is involved in the pathogenesis of many diseases. In the context of asthma, autophagy has been shown to be associated with inflammation, airway remodeling, and responsiveness to drug therapy. In-depth characterization of the role of autophagy in asthma can enhance the understanding of the pathogenesis, and provide a theoretical basis for the development of new biomarkers and targeted therapy for asthma. In this article, we focus on the relationship of autophagy and asthma, and discuss its implications for asthma pathogenesis and treatment.

MiR-506 targets polypyrimidine tract-binding protein 1 to inhibit airway inflammatory response and remodeling via mediating Wnt/β-catenin signaling pathway

BACKGROUND

Airway remodeling, which contributes to the clinical course of childhood asthma, occurs due to airway inflammation and is featured by anomalous biological behaviors of airway smooth muscle cells (ASMCs). microRNA (miRNA) plays an essential role in the etiopathogenesis of asthma.

OBJECTIVE

This research was aimed to characterize miR-506 in asthma and uncover potential regulatory machinery.

MATERIAL AND METHODS

The asthmatic cell model was established by treating ASMCs with transforming growth factor-beta1 (TGF-β1) and assessed by the levels of interleukin (IL)-1β and interferon gamma (IFN-γ). Using real-time quantitative polymerase chain reaction, mRNA expression of miR-506 and polypyrimidine tract-binding protein 1 (PTBP1) was measured. Cell counting kit-8 and Transwell migration tests were used for estimating the capacity of ASMCs to proliferate and migrate. Luciferase reporter assay was used to corroborate whether miR-506 was directly bound to PTBP1. Expression of PTBP1, collagen I and III, and essential proteins of the wingless-related integration (Wnt)/β-catenin pathway (β-catenin, c-MYC and cyclin D1) was accomplished by Western blot analysis. The involvement of Wnt/β-catenin signaling in asthma was confirmed by Wnt signaling pathway inhibitor (IWR-1).

RESULTS

miR-506 was poorly expressed in asthmatic tissues and cell model. Functionally, overexpression of miR-506 reduced aberrant proliferation, migration, inflammation and collagen deposition of ASMCs triggered by TGF-β1. Mechanically, miR-506 directly targeted the 3' untranslated region (3-UTR) of PTBP1 and had a negative regulation on PTBP1 expression. Moreover, overexpression of miR-506 suppressed the induction of Wnt/β-catenin pathway. The administration of IWR-1 further validated negative correlation between miR-506 and the Wnt/β-catenin pathway in asthma.

CONCLUSION

Our data indicated that targeting miR-506/PTBP1/Wnt/β-catenin axis might point in a helpful direction for treating asthma in children.

Recent miRNA Research in Asthma

PURPOSE OF REVIEW

The study of microRNA in asthma has revealed a vibrant new level of gene regulation underlying asthma pathology. Several miRNAs have been shown to be important in asthma, influencing various biological mechanisms which lead to asthma pathology and symptoms. In addition, miRNAs have been proposed as biomarkers of asthma affection status, asthma severity, and asthma treatment response. We review all recent asthma-miRNA work, while also presenting comprehensive tables of all miRNA results related to asthma.

RECENT FINDINGS

We here reviewed 63 recent studies published reporting asthma and miRNA research, and an additional 14 reviews of the same. We summarized the information for both adult and childhood asthma, as well as research on miRNAs in asthma-COPD overlap syndrome (ACOs), and virus-induced asthma exacerbations. We attempted to present a comprehensive collection of recently published asthma-associated miRNAs as well as tables of all published asthma-related miRNA results.

PLGA microspheres carrying miR-20a-5p improved intestinal epithelial barrier function in patients with Crohn's disease through STAT3-mediated inhibition of Th17 differentiation

BACKGROUND

Recent studies have shown that microRNAs (miRNAs) are aberrantly expressed in patients with Crohn's disease (CD). This suggests that the aberrant expression of miRNAs may contribute to the development of CD. Currently, the specific miRNAs involved in CD development have not been clearly identified. Therefore, we aimed to identify CD-associated miRNAs and explore their functions.

METHODS

miRNA microarray analysis was performed to screen for differentially expressed miRNAs in colon tissues from normal controls (NC) and CD patients. The identified miRNAs were validated using quantitative real-time PCR (qPCR). The therapeutic roles of miR-20a-5p mimics via the delivery of poly(lactic-co-glycolic acid) microspheres (PLGA MSs) were further investigated in IL-10^-/- mice with spontaneous chronic colitis that were used as a model of CD. The target genes of miR-20a-5p and the associated signaling pathways were identified through bioinformatic analysis and experimental verification of the interactions between the targets predicted by the algorithms and dysregulated mRNAs.

RESULTS

The analysis showed that miR-20a-5p was the most significantly downregulated miRNA in patients with CD. Treatment with PLGA MSs carrying miR-20a-5p significantly ameliorated the colitis, decreased mucosal inflammation, and improved epithelial barrier function. Bioinformatic analysis and experimental studies showed that miR-20a-5p inhibition enhanced Th17 differentiation and improved intestinal epithelial barrier function by targeting STAT3.

CONCLUSIONS

Downregulation of miR-20a-5p improved the intestinal epithelial barrier function and prevented CD development through the STAT3/IL-17 signaling pathway. Therefore, the delivery of miR-20a-5p by PLGA MSs may serve as a potential therapeutic strategy for CD treatment.

MiR-146a-5p accelerates sepsis through dendritic cell activation and glycolysis via targeting ATG7

To unveil the role and regulatory mechanism of miR-146a-5p in sepsis. A sepsis cell model was established via lipopolysaccharide (LPS)-induction in dendritic cells (DCs). The maturation of DCs was evaluated via flow cytometry. Gene expression was measured through reverse-transcription quantitative polymerase chain reaction (RT-qPCR). The concentrations of inflammation biomarkers were revealed via enzyme-linked immunosorbent assay (ELISA). The pathological and histological changes in lungs in the sepsis mice model were analyzed via hematoxylin and eosin (H&E) staining. In this study, the miR-146a-5p level was elevated in the serum of sepsis patients and LPS-induced DCs but decreased in the serums of cured sepsis patients. Furthermore, miR-146a-5p deletion alleviated the activation of T cells and attenuated the imbalance of Th17/Treg. Besides, ATG7 was validated as a target of miR-146a-5p. ATG7 elevation enhanced lactate production and glucose uptake in LPS-triggered DCs. Additionally, upregulation of ATG7 suppressed the protein levels of phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK), phospho protein kinase B (p-AKT), and phosphorylated signal transducer and activator for transcription 3 (p-STAT3). In addition, miR-146a-5p downregulation alleviated T-cell activation, inflammation, lactate production, and glucose uptake in sepsis mice. Moreover, the lung injury due to sepsis was also attenuated as a result of miR-146a-5p silencing. MiR-146a-5p aggravates sepsis through DCs activation and glycolysis via targeting ATG7.

Autophagy-Related Genes Are Involved in the Progression and Prognosis of Asthma and Regulate the Immune Microenvironment

Background

Autophagy has been proven to play an important role in the pathogenesis of asthma and the regulation of the airway epithelial immune microenvironment. However, a systematic analysis of the clinical importance of autophagy-related genes (ARGs) regulating the immune microenvironment in patients with asthma remains lacking.

Methods

Clustering based on the k-means unsupervised clustering method was performed to identify autophagy-related subtypes in asthma. ARG-related diagnostic markers in low-autophagy subtypes were screened, the infiltration of immune cells in the airway epithelium was evaluated by the CIBERSORT, and the correlation between diagnostic markers and infiltrating immune cells was analyzed. On the basis of the expression of ARGs and combined with asthma control, a risk prediction model was established and verified by experiments.

Results

A total of 66 differentially expressed ARGs and 2 subtypes were identified between mild to moderate and severe asthma. Significant differences were observed in asthma control and FEV1 reversibility between the two subtypes, and the low-autophagy subtype was closely associated with severe asthma, energy metabolism, and hormone metabolism. The autophagy gene SERPINB10 was identified as a diagnostic marker and was related to the infiltration of immune cells, such as activated mast cells and neutrophils. Combined with asthma control, a risk prediction model was constructed, the expression of five risk genes was supported by animal experiments, was established for ARGs related to the prediction model.

Conclusion

Autophagy plays a crucial role in the diversity and complexity of the asthma immune microenvironment and has clinical value in treatment response and prognosis.

MicroRNA-335-5p alleviates inflammatory response, airway fibrosis, and autophagy in childhood asthma through targeted regulation of autophagy related 5

Childhood asthma is the most universal chronic disease, with significant cases reported. Despite the current progress in treatment, prognosis remains poor and the existing drugs cause serious side effects. This investigation explored the mechanisms and use of miR-335-5p on childhood asthma therapy. MiR-335-5p and ATG5 expression was analyzed in clinical plasma samples through RT-qPCR. Airway smooth muscle cells (ASMCs) were cultured, and transfected with miR-335-5p mimic, miR-335-5p inhibitor, and pcDNA3.1-ATG5, or co-transfected with miR-335-5p mimic + pcDNA3.1-ATG5. Asthma cell models were constructed through TGF-β1, and animal models through ovalbumin (OVA). Monocyte-macrophage infiltration in bronchoalveolar lavage fluid (BALF) was determined by May-Grunwald-Giemsa staining, and collagen in lung tissue was assessed via Masson staining. Relationship between miR-335-5p and ATG5 was detected by dual-luciferase assay. Cell proliferation was detected by MTT assay. MiR-335-5p and ATG5 RNA expression was determined by RT-qPCR. Collagen I, collagen III, α-SMA, ATG5, LC3I/II, Beclin-1, and p62 protein expression levels in ASMCs were detected by western blot. MiR-335-5p expression was low, but ATG5 expression was high in childhood asthma. Versus OVA+ mimic NC group, the number of eosinophil and collagen in OVA+ miR-335-5p mimic group were reduced. In contrast to TGF-β1 + mimic NC group, TGF-β1 + miR-335-5p mimic group reduced inflammatory, airway fibrosis, and autophagy in ASMCs. ATG5 was miR-335-5p target. Overexpressing ATG5 significantly reversed the inhibitory effects of miR-335-5p on inflammatory response, fibrosis, and autophagy in ASMCs. Overall, the study concludes that MiR-335-5p alleviate inflammatory response, airway fibrosis, and autophagy in childhood asthma through targeted regulation of ATG5.