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Silicosis is an occupational disease caused by long-term inhalation of free silica, resulting in a significant global health burden. Its pathogenesis remains unclear, and there is no effective treatment. Proliferative and activated myofibroblasts play a key role in the development of silicosis. Traditional studies have focused on fibroblast proliferation and collagen secretion, neglecting their functional heterogeneity. With the advancement of omics research, more pathogenic fibroblast subgroups and their functions have been identified. In this study, we applied transcriptomics to analyze gene changes in primary lung fibroblasts during silicosis development using a mouse model. Our results indicate that DEGs are enriched in collagen secretion, ECM synthesis, leukocyte migration, and chemotaxis functions. Altered core genes are associated with immune cell recruitment and cell migration. Nrf2 agonists, known for anti-inflammatory and antioxidant properties, have shown potential therapeutic effects in fibrotic diseases. However, their effects on fibroblasts in silicosis are not fully understood. We used four common Nrf2 agonists to study gene expression changes in lung fibroblasts at the transcriptome level, combined with histopathological and biochemical methods, to investigate their effects on silicosis in mice. Results show that Nrf2 agonists can exert anti-silicosis fibrosis functions by downregulating genes like Fos and Egr1, involved in cell differentiation, proliferation, and inflammation. In conclusion, this study suggests that inflammation-related co-functions of fibroblasts may be a potential mechanism in silicosis pathogenesis. Targeting Nrf2 may be a promising strategy to alleviate oxidative stress and inflammation in silicosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Objective: To predict the targets of Bufei Huoxue capsule (, BFHX) using network pharmacology analysis and to explore its effects and functional targets in a silicotic rat model., Methods: The drug and disease targets were correlated through network pharmacology analysis to explore the targets and signaling pathways of BFHX affecting silicosis. NR8383 cells were cultured to verify the core genes and pathways. A rat model of silicosis was established to verify whether the mechanism behind SiO2-caused pulmonary fibrosis was alleviated by BFHX (0.82 g/kg) and how it affected key targets and pathways., Results: Overlapping BFHX and silicotic gene targets produced 159 interactive targets, and 55 were screened by network topology analysis. The results of gene ontology and Kyoto encyclopedia of genes and genomes enrichment analyses suggested that BFHX could affect silicosis through the nucleotide-like receptor containing pyrin domain 3 (NLRP3) inflammasome. In NR8383 cells, the expression of core genes related to the NLRP3 inflammasome could be inhibited by BFHX treatment. BFHX reduced the degree of alveolitis and collagen deposition, attenuating pulmonary fibrosis in SiO2-induced rat model. Pulmonary macrophage pyroptosis after SiO2 exposure was observed under transmission electron microscopy. BFHX alleviated the morphological characteristics of pyroptosis. BFHX also reduced the expression of NLRP3, caspase-1, interleukin-1 beta (IL-1β), IL-18, IL-6, and tumor necrosis factor-alpha in lung tissues of silicotic rat model. BFHX affected the K ion content in bronchoalveolar lavage fluid when assessed by energy dispersive spectrometer testing. The expression of CD68+ and CD206+ were also reduced after BFHX intervention., Conclusion: NOD-like receptor signaling is vital for BFHX's effects on silicosis. It exerts anti-pulmonary fibrosis effects by inhibiting pulmonary macrophage pyroptosis and polarization through NLRP3 inflammasome activation.

Background: Silicosis and coal worker's pneumoconiosis primarily result from exposure to silica and coal dust. Despite similar exposure levels, individuals exhibit varying responses. This study aimed to address these gaps to explore the genetic factors influencing the development, severity, and associated complications., Methods: A systematic literature search was performed across four databases-PubMed, Embase, Web of Science, and Cochrane Library-until July, 2023. Qualitative and quantitative analyses were applied to identify candidate genes., Results: This study involved 83 articles and encompassed 545 individual studies, reviewing a total of 378 gene loci. After rigorous evaluation, we selected 8 candidate genes (TNFα-308, TNFα-238, GSTT1, IL-1α + 4845, IL-1β-511, IL-1β + 3953, IL-1RA + 2018, and IL-6-174) for meta-analysis. The analysis revealed that allele A of TNFα-308, allele A of TNFα-238, and allele C of IL-1RA + 2018 were identified as risk factors for the development of diseases., Conclusions: This study established associations between specific genetic polymorphisms (TNFα-308, TNFα-238, and IL-1RA + 2018) and susceptibility to silicosis and coal worker's pneumoconiosis., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interest: The authors declare no competing interests., (© 2024. The Author(s).)

Background: Silica particles can cause silicosis, a disease characterized by diffuse fibrosis of the lungs. Various signaling pathways composed of different types of cells and cytokines are involved in the development of silicosis. Exosomes have become a research hotspot recently. However, the role of exosomal microRNA (miRNA) in silicosis remains unclear., Methods: In this study, we generated exosomal miRNA sequences from exosomes isolated from bronchoalveolar lavage fluid (BALF) of silicosis patients and the control group by high-throughput sequencing. Functional annotation and analysis of miRNA identified key target miRNAs. Levels of target miRNAs were analyzed in patient and animal samples and cells. Effects of increased miRNA were assessed through protein levels in target signaling pathways in cells treated with silica, miRNA mimics, and inhibitors., Results: Our study identified 40 up-regulated and 70 down-regulated miRNAs, with miR-552-3p and its putative target gene Caveolin 1 (CAV1) as targets for further research. We found that the levels of exosomal miR-552-3p increased in silicosis patients' BALF samples, silicosis model mice, and A549 cells exposed to silica. Inhibition of miR-552-3p suppressed the expression of fibrosis markers. The increased miR-552-3p leads to the up-regulation of fibronectin and α-smooth muscle actin (α-SMA) and the suppression of caveolin 1 in fibroblast cells. Mitogen-activated protein kinase (MAPK) signaling pathways are activated in cells treated with silica and miR-552-3p mimics., Conclusions: These results help to understand exosomal miRNA-mediated intercellular communication and its key role in fibroblast activation and silicosis., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jie Meng reports financial support was provided by National Natural Science Foundation of China., (Copyright © 2024. Published by Elsevier B.V.)

Background: Pulmonary Tuberculosis (PTB) is a significant global health issue due to its high incidence, drug resistance, contagious nature, and impact on people with compromised immune systems. As mentioned by the World Health Organization (WHO), TB is responsible for more global fatalities than any other infectious illness. On the other side, WHO also claims that noncommunicable diseases (NCDs) kill 41 million people yearly worldwide. In this regard, several studies suggest that PTB and NCDs are linked in various ways and that people with PTB are more likely to acquire NCDs. At the same time, NCDs can increase susceptibility to active TB infection. Furthermore, because of potential drug interactions and therapeutic challenges, treating individuals with both PTB and NCDs can be difficult. This study focuses on seven NCDs (lung cancer (LC), diabetes mellitus (DM), Parkinson's disease (PD), silicosis (SI), chronic kidney disease (CKD), cardiovascular disease (CVD), and rheumatoid arthritis (RA)) and rigorously presents the genetic relationship with PTB regarding shared genes and outlines possible treatment plans., Objectives: BlueThis study aims to identify the drug components that can regulate abnormal gene expression in NCDs. The study will reveal hub genes, potential biomarkers, and drug components associated with hub genes through statistical measures. This will contribute to targeted therapeutic interventions., Methods: Numerous investigations, including protein-protein interaction (PPI), gene regulatory network (GRN), enrichment analysis, physical interaction, and protein-chemical interaction, have been carried out to demonstrate the genetic correlation between PTB and NCDs. During the study, nine shared genes such as TNF, IL10, NLRP3, IL18, IFNG, HMGB1, CXCL8, IL17A, and NFKB1 were discovered between TB and the above-mentioned NCDs, and five hub genes (NFKB1, TNF, CXCL8, NLRP3, and IL10) were selected based on degree values., Results and Conclusion: In this study, we found that all of the hub genes are linked with the 10 drug components, and it was observed that aspirin CTD 00005447 was mostly associated with all the other hub genes. This bio-informatics study may help researchers better understand the cause of PTB and its relationship with NCDs, and eventually, this can lead to exploring effective treatment plans., Competing Interests: No Competing Interests., (Copyright: © 2024 Mahjabeen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Long non-coding RNAs play a key role in silicosis, a fatal fibrotic lung disease, and there is an urgent need to develop new treatment targets. Long intergenic non-protein-coding RNA 3047 (LINC03047) is associated with cancer, but its role and mechanism in the progression of silicosis require further elucidation. This study investigated the function of LINC03047 in the epithelial-mesenchymal transition (EMT) during silicosis progression. LINC03047 expression was upregulated in SiO 2 -treated BEAS-2B and A549 cells, promoting SiO 2 -induced ferroptosis and subsequent EMT. Moreover, knockdown of LINC03047 significantly decreased the expression of solute carrier family 39 member 14 (SLC39A14), a ferrous iron transporter, and inhibition of SLC39A14 alleviated the ferroptosis and EMT caused by LINC03047 overexpression. We further investigated that NF-κB p65 (RELA) was critical for LINC03047 transcription in SiO 2 -treated BEAS-2B and A549 cells. In vivo experiments showed that SLC39A14 deficiency improved SiO 2 -induced lipid peroxidation and EMT. Collectively, our study reveals the function of the RELA/LINC03047/SLC39A14 axis in SiO 2 -induced ferroptosis and EMT, thereby contributing to the identification of novel drug targets for silicosis therapy., Competing Interests: Declaration of competing interest None., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Engineered stone-associated silicosis is characterised by a rapid progression of fibrosis linked to a shorter duration of exposure. To date, there is lack of information about molecular pathways that regulates disease development and the aggressiveness of this form of silicosis. Therefore, we compared transcriptome responses to different engineered stone samples and standard silica. We then identified and further tested a stone dust specific pathway (aryl hydrocarbon receptor [AhR]) in relation to mitigation of adverse lung cell responses. Cells (epithelial cells, A549; macrophages, THP-1) were exposed to two different benchtop stone samples, standard silica and vehicle control, followed by RNA sequencing analysis. Bioinformatics analyses were conducted, and the expression of dysregulated AhR pathway genes resulting from engineered stone exposure was then correlated with cytokine responses. Finally, we inhibited AhR pathway in cells pretreated with AhR antagonist and observed how this impacted cell cytotoxicity and inflammation. Through transcriptome analysis, we identified the AhR pathway genes (CYP1A1, CYP1B1 and TIPARP) that showed differential expression that was unique to engineered stones and common between both cell types. The expression of these genes was positively correlated with interleukin-8 production in A549 and THP-1 cells. However, we only observed a mild effect of AhR pathway inhibition on engineered stone dust induced cytokine responses. Given the dual roles of AhR pathway in physiological and pathological processes, our data showed that expression of AhR target genes could be markers for assessing toxicity of engineered stones; however, AhR pathway might not play a significant pathologic role in engineered stone-associated silicosis., (© 2024 The Author(s). Journal of Applied Toxicology published by John Wiley & Sons Ltd.)

Silicosis is a systemic disease caused by long-term exposure to high concentrations of free silica dust particles in the workplace. It is characterized by a persistent inflammatory response, fibroblast proliferation, and excessive collagen deposition, leading to pulmonary interstitial fibrosis. Epithelial interstitial transformation (EMT) can cause epithelial cells to lose their tight junctions, cell polarity, and epithelial properties, thereby enhancing the properties of interstitial cells, which can lead to the progression of fibrosis and the formation of scar tissue. Integrin 1 (ITGB1) is considered an important factor for promoting EMT and tumor invasion in a variety of tumors and also plays an important role in the progression of fibrotic diseases. Therefore, ITGB1 can be used as a potential target for the treatment of silicosis. In this study, we found that silica exposure induced epithelial-mesenchymal transformation in rats and that the expression of integrin ITGB1 was elevated along with the EMT. We used CRISPR/Cas9 technology to construct integrin ITGB1 knockdown cell lines for in vitro experiments. We compared the expression of the EMT key proteins E-cadherin and vimentin in the ITGB1 knockdown cells and wild-type cells simultaneously stimulated by silica and detected the aggregation point distribution of E-cadherin and vimentin in the cells using laser confocal microscopy. Our results showed that ITGB1 knockout inhibited the ITGB1/ILK/Snail signaling pathway and attenuated the EMT occurrence compared to control cells. These results suggested that ITGB1 is associated with silica-induced EMT and may be a potential target for the treatment of silicosis.

Assessing the association between candidate single-nucleotide polymorphisms (SNPs) identified by multi-omics approaches and susceptibility to silicosis. RNA-seq analysis was performed to screen the differentially expressed mRNAs in the fibrotic lung tissues of mice exposed to silica particles. Following this, we integrated the SNPs located in the above human homologenes with the silicosis-related genome-wide association study (GWAS) data to select the candidate SNPs. Then, expression quantitative trait locus (eQTL)-SNPs were identified by the GTEx database. Next, we validated the associations between the functional eQTL-SNPs and silicosis susceptibility by additional case-control study. And the contribution of the identified SNP and its host gene in the fibrosis process was further validated by functional experiments. A total of 12 eQTL-SNPs were identified in the screening stage. The results of the validation stage suggested that the variant T allele of rs419540 located in IL12RB1 significantly increased the risk of developing silicosis [additive model: odds ratio (OR) = 1.78, 95% confidence interval (CI) 1.11-2.85, P = 0.017]. Furthermore, the combination of GWAS and the results of validation stage also indicated that the variant T allele of rs419540 in IL12RB1 was associated with increased silicosis risk (additive model: OR = 2.07, 95% CI 1.38-3.12, P < 0.001). Additionally, after knockdown or overexpression of IL12RB1, the levels of pro-inflammatory factors, such as IL-12, IFN-γ, and other pro-inflammatory factors, were correspondingly decreased or increased. The novel eQTL-SNP, rs419540, might increase the risk of silicosis by modulating the expression levels of IL12RB1., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: To explore the mechanisms of Yangqing Chenfei formula (, YCF) in the treatment of silicosis through a comprehensive strategy consisting of serum pharmacochemistry, network pharmacology analysis, and in vitro validation., Methods: An ultrahigh-performance liquid chroma-tography-tandem mass spectrometry method was used to confirm the active components in YCF-medicated serum. Then, we obtained targets for active components and genes for silicosis from multiple databases. Furthermore, a protein-protein interaction network was constructed, and Kyoto Encyclopedia of Genes and Genomes pathway and biological process analyses were conducted to elucidate the mechanisms of YCF for the treatment of silicosis. Finally, we validated the important components and mechanisms in vitro ., Results: Altogether, 19 active components were identified from rat serum after YCF administration. We identified 724 targets for 19 components, which were mainly related to inflammation [phosphatidy linositol 3 kinase/protein kinase B, forkhead box O, hypoxia inducible factor, and T-cell receptor signaling pathway, nitric oxide biosynthetic process], fibrotic processes [vascular endothelial growth factor signaling pathway, extracellular signal regulated kinase (ERK) 1 and ERK2 cascade, smooth muscle cell proliferation], and apoptosis (negative regulation of apoptotic process). In addition, 218 genes for silicosis were identified and were mainly associated with the inflammatory response and immune process [cytokine?cytokine receptor interaction, tumor necrosis factor alpha (TNF-α), toll-like receptor, and nucleotide binding oligomerization domain-like receptor signaling pathway]. Taking an intersection of active component targets and silicosis genes, we obtained 61 common genes that were mainly related to the inflammatory response and apoptosis, such as the phosphatidylinositol-3-kinase/protein kinase B signaling pathway, mitogen activated protein kinases signaling pathway, TNF signaling pathway, toll-like receptor signaling pathway, biosynthesis of nitric oxide, and apoptotic process. In the herb-component-gene-pathway network, paeoniflorin, rutin and nobiletin targeted the most genes. In vitro , paeoniflorin, rutin and nobiletin decreased the mRNA levels of inflammatory factors [interleukin (IL)-6, TNF-α, and IL-1β], suppressed p-AKT and cleaved caspase-3, and increased B cell lymphoma (Bcl)-2 protein expression in silica-induced macrophages in a concentration-dependent manner., Conclusion: YCF could significantly relieve the inflammatory response of silicosis via suppression of the AKT/Bcl-2/Caspase-3 pathway.

To explore the association between apaQTL/eQTL-SNPs and the susceptibility to silicosis. A silicosis-related GWAS was initially conducted to screen for single nucleotide polymorphisms (SNPs) associated with the risk of silicosis. Candidate SNPs with apaQTL and eQTL functions were then obtained from the 3'aQTL-atlas and GTEx databases. Subsequently, additional case-control studies were performed to validate the relationship between the candidate apaQTL/eQTL-SNPs and the risk of silicosis. Finally, experiments were conducted to illustrate APA events occurring at different alleles of the identified apaQTL/eQTL-SNPs. The combined results of the GWAS and iMLDR validations indicate that the variant T allele of the rs2974341 located on SMIM19 (additive model: OR = 0.66, the 95% CI = 0.53-0.84, P = 0.001) and the variant T allele of the rs2390488 located on TMTC4 (additive model: OR = 0.72, 95% CI = 0.57-0.90, P = 0.005) were significantly associated with decreased risk of developing silicosis susceptibility. Furthermore, 3'RACE experiments verified the presence of two poly (A) sites (proximal and distal) in SMIM19, rs2974341 may remotely regulate the binding between miRNA-3646 and SMIM19 with its high LD locus rs2974353 to affect the expression level of SMIM19. The rs2974341 variant T allele may contribute to the generation of the shorter 3'UTR transcript of SMIM19 and affect the binding of miRNA-3646 to the target gene SMIM19. The apaQTL/eQTL-SNPs may provide new perspectives for evaluating the regulatory function of SNPs in the development of silicosis., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Silicosis is a systemic disease caused by long-term inhalation of free SiO 2 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., (© 2024 Wiley Periodicals LLC.)

Recent research has hinted at a potential connection between silicosis, a fibrotic lung disease caused by exposure to crystalline silica particles, and cuproptosis. The aim of the study was to explore how cuproptosis-related genes (CRGs) may influence the development of silicosis and elucidate the underlying mechanisms. An analysis of genes associated with both silicosis and cuproptosis was conducted. Key gene identification was achieved through the application of two machine learning techniques. Additionally, the correlation between these key genes and immune cell populations was explored and the critical pathways were discerned. To corroborate our findings, the expression of key genes was verified in both a publicly available silica-induced mouse model and our own silicosis mouse model. A total of 12 differentially expressed CRGs associated with silicosis were identified. Further analysis resulted in the identification of 6 CRGs, namely LOX, SPARC, MOXD1, ALB, MT-CO2, and AOC2. Elevated immune cell infiltration of CD8 T cells, regulatory T cells, M0 macrophages, and neutrophils in silicosis patients compared to healthy controls was indicated. Validation in a silica-induced pulmonary fibrosis mouse model supported SPARC and MT-CO2 as potential signature genes for the prediction of silicosis. These findings highlight a strong association between silicosis and cuproptosis. Among CRGs, LOX, SPARC, MOXD1, ALB, MT-CO2, and AOC2 emerged as pivotal players in the context of silicosis by modulating CD8 T cells, regulatory T cells, M0 macrophages, and neutrophils., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Long-term exposure to inhalable silica particles may lead to severe systemic pulmonary disease, such as silicosis. Exosomes have been demonstrated to dominate the pathogenesis of silicosis, but the underlying mechanisms remain unclear. Therefore, this study aimed to explore the roles of exosomes by transmitting miR-107, which has been linked to the toxic pulmonary effects of silica particles. We found that miR-107, miR-122-5p, miR-125a-5p, miR-126-5p, and miR-335-5p were elevated in exosomes extracted from the serum of patients with silicosis. Notably, an increase in miR-107 in serum exosomes and lung tissue was observed in the experimental silicosis mouse model, while the inhibition of miR-107 reduced pulmonary fibrosis. Moreover, exosomes helped the migration of miR-107 from macrophages to lung fibroblasts, triggering the transdifferentiation of cell phenotypes. Further experiments demonstrated that miR-107 targets CDK6 and suppresses the expression of retinoblastoma protein phosphorylation and E2F1, resulting in cell-cycle arrest. Overall, micron-grade silica particles induced lung fibrosis through exosomal miR-107 negatively regulating the cell cycle signaling pathway. These findings may open a new avenue for understanding how silicosis is regulated by exosome-mediated cell-to-cell communication and suggest the prospect of exosomes as therapeutic targets., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Pneumoconiosis is one of the most serious occupational diseases worldwide. Silicosis due to prolonged inhalation of free silica dust during occupational activities is one of the main types. Cuproptosis is a newly discovered mode of programmed cell death characterized by the accumulation of free copper in the cell, which ultimately leads to cell death. Increased copper in the serum of silicosis patients, suggests that the development of silicosis is accompanied by changes in copper metabolism, but whether cuproptosis is involved in the progression of silicosis is actually to be determined. To test this hypothesis, we screened the genetic changes in patients with idiopathic fibrosis by bioinformatics methods and predicted and functionally annotated the cuproptosis-related genes among them. Subsequently, we established a mouse silicosis model and detected the concentration of copper ions and the activity of ceruloplasmin (CP) in serum, as well as changes of the concentration of copper and cuproptosis related genes in mouse lung tissues. We identified 9 cuproptosis-related genes among the differential genes in patients with IPF at different times and the tissue-specific expression levels of ferredoxin 1 (FDX1) and Lipoyl synthase (LIAS) proteins. Furthermore, serum CP activity and copper ion levels in silicosis mice were elevated on days 7th and 56th after silica exposure. The expression of CP in mouse lung tissue elevated at all stages after silica exposure. The mRNA level of FDX1 decreased on days 7th and 56th, and the protein level remained in accordance with the mRNA level on day 56th. LIAS and Dihydrolipoamide dehydrogenase (DLD) levels were downregulated at all times after silica exposure. In addition, Heatshockprotein70 (HSP70) expression was increased on day 56. In brief, our results demonstrate that there may be cellular cuproptosis during the development of experimental silicosis in mice and show synchronization with enhanced copper loading in mice., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The widespread manufacture of silica and its extensive use, and potential release of silica into the environment pose a serious human health hazard. Silicosis, a severe global public health issue, is caused by exposure to silica, leading to persistent inflammation and fibrosis of the lungs. The underlying pathogenic mechanisms of silicosis remain elusive. Lung microbiota dysbiosis is associated with the development of inflammation and fibrosis. However, limited information is currently available regarding the role of lung microbiota in silicosis. The study therefore is designed to conduct a comprehensive analysis of the role of lung microbiota dysbiosis and establish a basis for future investigations into the potential mechanisms underlying silicosis. Here, the pathological and biochemical parameters were used to systematically assessed the degree of inflammation and fibrosis following silica exposure and treatment with combined antibiotics. The underlying mechanisms were studied via integrative multi-omics analyses of the transcriptome and microbiome. Analysis of 16S ribosomal DNA revealed dysbiosis of the microbial community in silicosis, characterized by a predominance of gram-negative bacteria. Exposure to silica has been shown to trigger lung inflammation and fibrosis, leading to an increased concentration of lipopolysaccharides in the bronchoalveolar lavage fluid. Furthermore, Toll-like receptor 4 was identified as a key molecule in the lung microbiota dysbiosis associated with silica-induced lung fibrosis. All of these outcomes can be partially controlled through combined antibiotic administration. The study findings demonstrate that the dysbiosis of lung microbiota enhances silica-induced fibrosis associated with the lipopolysaccharides/Toll-like receptor 4 pathway and provided a promising target for therapeutic intervention of silicosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Long-term silica particle exposure leads to interstitial pulmonary inflammation and fibrosis, called silicosis. Silica-activated macrophages secrete a wide range of cytokines resulting in persistent inflammation. In addition, silica-stimulated activation of fibroblast is another checkpoint in the progression of silicosis. The pathogenesis after silica exposure is complex, involving intercellular communication and intracellular signaling pathway transduction, which was ignored previously. Exosomes are noteworthy because of their crucial role in intercellular communication by delivering bioactive substances, such as lncRNA. However, the expression profile of exosomal lncRNA in silicosis has not been reported yet. In this study, exosomes were isolated from the peripheral serum of silicosis patients or healthy donors. The exosomal lncRNAs were profiled using high-throughput sequencing technology. Target genes were predicted, and functional annotation was performed using differentially expressed lncRNAs. Eight aberrant expressed exosomal lncRNAs were considered to play a key role in the process of silicosis according to the OPLS-DA. Furthermore, the increased expression of lncRNA MSTRG.43085.16 was testified in vitro. Its target gene PARP1 was critical in regulating apoptosis based on bioinformatics analysis. In addition, the effects of exosomes on macrophage apoptosis and fibroblast activation were checked based on a co-cultured system. Our findings suggested that upregulation of lncRNA MSTRG.43085.16 could regulate silica-induced macrophage apoptosis through elevating PARP1 expression, and promote fibroblast activation, implying that the exosomal lncRNA MSTRG.43085.16 might have potential as a biomarker for the early diagnosis of silicosis.

Silicosis is a severe worldwide occupational hazard, characterized with lung tissue inflammation and irreversible fibrosis caused by crystalline silicon dioxide. As the most common and abundant internal modification of messenger RNAs or noncoding RNAs, N6-methyladenosine (m6A) methylation is dysregulated in the chromic period of silicosis. However, whether m6A modification is involved in the early phase of silica-induced pulmonary inflammation and fibrosis and its specific effector cells remains unknown. In this study, we established a pulmonary inflammation and fibrosis mouse model by silica particles on day 7 and day 28. Then, we examined the global m6A modification level by m6A dot blot and m6A RNA methylation quantification kits. The key m6A regulatory factors were analyzed by RTqPCR, Western blot, and immunohistochemistry (IHC) in normal and silicosis mice. The results showed that the global m6A modification level was upregulated in silicosis lung tissues with the demethylase FTO suppression after silica exposure for 7 days and 28 days. METTL3, METTL14, ALKBH5, and other m6A readers had no obvious differences between the control and silicosis groups. Then, single-cell sequencing analysis revealed that thirteen kinds of cells were recognized in silicosis lung tissues, and the mRNA expression of FTO was downregulated in epithelial cells, endothelial cells, fibroblasts, and monocytes. These results were further confirmed in mouse lung epithelial cells (MLE-12) exposed to silica and in the peripheral blood mononuclear cells of silicosis patients. In conclusion, the high level of global m6A modification in the early stage of silicosis is induced by the downregulation of the demethylase FTO, which may provide a novel target for the diagnosis and treatment of silicosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Until now, the specific pathogenesis of silicosis is not clear. Exosomal miRNAs, as a newly discovered intercellular communication medium, play an important role in many diseases. Our previous research found that serum exosomal miR125a-5p was increased in silicosis patients by miRNAs high-throughput sequencing. TRAF6, is a target gene of miR125a-5p, which is involved in T-cell differentiation. Furthermore, results from animal study indicate that knockdown of miR-125a-5p can regulate T lymphocyte subsets and significantly reduce pulmonary fibrosis by targeting TRAF6. However, the level of serum exosomal miR125a-5p in silicosis patients has not been reported, the role of macrophages-secreted exosomal miR-125a-5p in regulating T cell differentiation to promote fibroblast transdifferentiation (FMT) remains unknown. In this study, the levels of serum exosomal miR125a-5p and serum TGF-β1, IL-17A, IL-4 cytokines in silicosis patients were elevated, with the progression of silicosis, the level of serum exosomal miR125a-5p and serum IL-4 were increased; thus, the serum level of IFN-γ was negatively correlated with the progression of silicosis. In vitro, the levels of miR125a-5p in macrophages, exosomes, and T cells stimulated by silica were significantly increased. When the mimic was transfected into T cells, which directly suppressed TRAF6 and caused the imbalance of T cells differentiation, induced FMT. To sum up, these results indicate that exosomal miR-125a-5p may by targeting TRAF6 of T cells, induces the activation and apoptosis of T cells and the remodeling of Th1/Th2 and Th17/Tregs distribution, ultimately promotes FMT. Suggesting that exosomal miR-125a-5p may be a potential therapeutic target for silicosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Silicosis is a fatal occupational respiratory disease caused by the prolonged inhalation of respirable silica. The core event of silicosis is the heightened activity of fibroblasts, which excessively synthesize extracellular matrix (ECM) proteins. Our previous studies have highlighted that human umbilical cord mesenchymal stem cell-derived extracellular vesicles (hucMSC-EVs) hold promise in mitigating silicosis and the significant role played by microRNAs (miRNAs) in this process. Delving deeper into this mechanism, we found that miR-148a-3p was the most abundant miRNA of the differential miRNAs in hucMSC-EVs, with the gene heat shock protein 90 beta family member 1 (Hsp90b1) as a potential target. Notably, miR-148a-3p's expression was downregulated during the progression of silica-induced pulmonary fibrosis both in vitro and in vivo, but was restored after hucMSC-EVs treatment ( p < 0.05). Introducing miR-148a-3p mimics effectively hindered the collagen synthesis and secretion of fibroblasts induced by transforming growth factor-β1 (TGF-β1) ( p < 0.05). Confirming our hypothesis, Hsp90b1 was indeed targeted by miR-148a-3p, with significantly reduced collagen activity in TGF-β1-treated fibroblasts upon Hsp90b1 inhibition ( p < 0.05). Collectively, our findings provide compelling evidence that links miR-148a-3p present in hucMSC-EVs with the amelioration of silicosis, suggesting its therapeutic potential by specifically targeting Hsp90b1, thereby inhibiting fibroblast collagen activities. This study sheds light on the role of miR-148a-3p in hucMSC-EVs, opening avenues for innovative therapeutic interventions targeting molecular pathways in pulmonary fibrosis.

Silicosis is a progressive pulmonary fibrosis disease caused by long-term inhalation of a large amount of free crystalline silica, which seriously threatens the health of relevant workers and causes a huge amount of disease burden. The pathogenesis of silicosis is complex and unclear, it has been reported that long non coding RNA (lncRNA) plays an important role in the pathogenesis of silicosis. In order to improve the understanding of the disease and provide directions for the prevention and treatment of silicosis, this article reviewed the mechanism of lncRNA in the pathogenesis and disease progression of silicosis.

Silicosis as an occupational lung disease has been present in our lives for centuries. Research studies have already developed and implemented many animal models to study the pathogenesis and molecular basis of the disease and enabled the search for treatments. As all experimental animal models used to date have their advantages and disadvantages, there is a continuous search for a better model, which will not only accelerate basic research, but also contribute to clinical aspects and drug development. We review here, for the first time, the main animal models developed to date to study silicosis and the unique advantages of the zebrafish model that make it an optimal complement to other models. Among the main advantages of zebrafish for modelling human diseases are its ease of husbandry, low maintenance cost, external fertilisation and development, its transparency from early life, and its amenability to chemical and genetic screening. We discuss the use of zebrafish as a model of silicosis, its similarities to other animal models and the characteristics of patients at molecular and clinical levels, and show the current state of the art of inflammatory and fibrotic zebrafish models that could be used in silicosis research., Competing Interests: Conflict of interest: All authors have nothing to disclose., (Copyright ©The authors 2023.)

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., (© 2023 The Authors. The Journal of Gene Medicine published by John Wiley & Sons Ltd.)

Chronic exposure to silica can lead to silicosis, one of the most serious occupational lung diseases worldwide, for which there is a lack of effective therapeutic drugs and tools. Epithelial mesenchymal transition plays an important role in several diseases; however, data on the specific mechanisms in silicosis models are scarce. We elucidated the pathogenesis of pulmonary fibrosis via single-cell transcriptome sequencing and constructed an experimental silicosis mouse model to explore the specific molecular mechanisms affecting epithelial mesenchymal transition at the single-cell level. Notably, as silicosis progressed, glycoprotein non-metastatic melanoma protein B (GPNMB) exerted a sustained amplification effect on alveolar type II epithelial cells, inducing epithelial-to-mesenchymal transition by accelerating cell proliferation and migration and increasing mesenchymal markers, ultimately leading to persistent pulmonary pathological changes. GPNMB participates in the epithelial-mesenchymal transition in distant lung epithelial cells by releasing extracellular vesicles to accelerate silicosis. These vesicles are involved in abnormal changes in the composition of the extracellular matrix and collagen structure. Our results suggest that GPNMB is a potential target for fibrosis prevention., (© 2023. The Author(s).)

Silicosis is a refractory pneumoconiosis of unknown etiology that is characterized by diffuse lung fibrosis, and microRNA (miRNA) dysregulation is connected to silicosis. Emerging evidence suggests that miRNAs modulate pulmonary fibrosis through autophagy; however, its underlying molecular mechanism remains unclear. In agreement with miRNA microarray analysis, the qRT-PCR results showed that miR-29a-3p was significantly decreased in the pulmonary fibrosis model both in vitro and in vivo. Increased autophagosome was observed via transmission electron microscopy in lung epithelial cell models and lung tissue of silicosis mice. The expression of autophagy-related proteins LC3α/β and Beclin1 were upregulated. The results from using 3-methyladenine, an autophagy inhibitor, or rapamycin, an autophagy inducer, together with TGF-β1, indicated that autophagy attenuates fibrosis by protecting lung epithelial cells. In TGF-β1-treated TC-1 cells, transfection with miR-29a-3p mimics activated protective autophagy and reduced alpha-smooth muscle actin and collagen I expression. miRNA TargetScan predicted, and dual-luciferase reporter experiments identified Akt3 as a direct target of miR-29a-3p. Furthermore, Akt3 expression was significantly elevated in the silicosis mouse model and TGF-β1-treated TC-1 cells. The mammalian target of rapamycin (mTOR) is a central regulator of the autophagy process. Silencing Akt3 inhibited the transduction of the mTOR signaling pathway and activated autophagy in TGF-β1-treated TC-1 cells. These results show that miR-29a-3p overexpression can partially reverse the fibrotic effects by activating autophagy of the pulmonary epithelial cells regulated by the Akt3/mTOR pathway. Therefore, targeting miR-29a-3p may provide a new therapeutic strategy for silica-induced pulmonary fibrosis.

Silicosis is an occupational lung disease that is common worldwide. In recent years, coronavirus disease 2019 (COVID-19) has provided daunting challenges to public healthcare systems globally. Although multiple studies have shown a close link between COVID-19 and other respiratory diseases, the inter-relational mechanisms between COVID-19 and silicosis remain unclear. This study aimed to explore the shared molecular mechanisms and drug targets of COVID-19 and silicosis. Gene expression profiling identified four modules that were most closely associated with both diseases. Furthermore, we performed functional analysis and constructed a protein-protein interaction network. Seven hub genes (budding uninhibited by benzimidazoles 1 [BUB1], protein regulator of cytokinesis 1 [PRC1], kinesin family member C1 [KIFC1], ribonucleotide reductase regulatory subunit M2 [RRM2], cyclin-dependent kinase inhibitor 3 [CDKN3], Cyclin B2 [CCNB2], and minichromosome maintenance complex component 6 [MCM6]) were involved in the interaction between COVID-19 and silicosis. We investigated how diverse microRNAs and transcription factors regulate these seven genes. Subsequently, the correlation between the hub genes and infiltrating immune cells was explored. Further in-depth analyses were performed based on single-cell transcriptomic data from COVID-19, and the expression of hub-shared genes was characterized and located in multiple cell clusters. Finally, molecular docking results reveal small molecular compounds that may improve COVID-19 and silicosis. The current study reveals the common pathogenesis of COVID-19 and silicosis, which may provide a novel reference for further research., (© 2023. Fondazione Società Italiana di Neurologia.)

Silicosis is one of several potentially fatal occupational pathologies caused by the prolonged inhalation of respirable crystalline silica. Previous studies have shown that lung epithelial-mesenchymal transition (EMT) plays a significant role in the fibrosis effect of silicosis. Human umbilical cord mesenchymal stem cells-derived Extracellular vesicles (hucMSC-EVs) have attracted great interest as a potential therapy of EMT and fibrosis-related diseases. However, the potential effects of hucMSC-EVs in inhibiting EMT in silica-induced fibrosis, as well as its underlying mechanisms, remain largely unknown. In this study, we used the EMT model in MLE-12 cells and observed the effects and mechanism of hucMSC-EVs inhibition of EMT. The results revealed that hucMSC-EVs can indeed inhibit EMT. MiR-26a-5p was highly enriched in hucMSC-EVs but was down-regulated in silicosis mice. We found that miR-26a-5p in hucMSC-EVs was over-expressed after transfecting miR-26a-5p expressing lentivirus vectors into hucMSCs. Subsequently, we explored if miR-26a-5p, attained from hucMSC-EVs, was involved in inhibiting EMT in silica-induced lung fibrosis. Our findings suggested that hucMSC-EVs could deliver miR-26a-5p into MLE-12 cells and cause the inhibition of the Adam17/Notch signalling pathway to ameliorate EMT in silica-induced pulmonary fibrosis. These findings might represent a novel insight into treating silicosis fibrosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The purpose of this study was to characterize the microRNA (miRNA) profile of the lung tissues from coal workers' pneumoconiosis (CWP) and silicosis and to analyze the changes in downstream genes, biological processes, and signaling pathways based on the differently expressed miRNAs. Lung tissues from three CWP patients, eight silicosis patients, and four healthy controls were collected and analyzed for their miRNA profiles using Affymetrix® GeneChip® miRNA Arrays. Differentially expressed miRNAs (DEMs) were identified between the different groups. The miRanda and TargetScan databases were used to predict the putative target genes, and volcano and heat maps were drawn. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analyses were then performed to screen the DEMs-associated biological process and signaling pathways, respectively. Further identification with a comprehensive literature research involving particle exposure, fibrosis, inflammation and lung cancer were used to further screen DEMs of CWP and silicosis. Microarray data showed that 375 and 88 miRNAs were differentially expressed in CWP and silicosis lung tissues compared with healthy lung tissues, while 34 miRNAs were differentially expressed in CWP compared with silicosis lung tissues. The GO and KEGG pathway analyses showed that, the target genes were mainly enriched in the TGF-β, MAPK, p53 and other signal pathways. These results provided insight into the miRNA-related underlying mechanisms of CWP and silicosis, and they provided new clues for miRNAs as biomarkers for the diagnosis and differential diagnosis of these two diseases.

Silicosis is a progressive inflammatory disease with poorly defined mechanisms and limited therapeutic options. Recent studies found that microRNAs (miRNAs) and circular RNAs (circRNAs) were involved in the development of respiratory diseases; however, the function of non-coding RNAs in silicosis was still needed to be further explored. We found that miR-223-3p was significantly decreased in macrophages and lung tissues of mice after silica treatment, which were consistent with the results of GEO database microarray analysis. Notably, NLRP3 is a target gene downstream of miR-223-3p. And circular RNA PWWP2A (circPWWP2A) was significantly elevated after silica stimulation. To elucidate the role of these RNAs in silica-induced inflammation in macrophages and lung tissues, we investigated the upstream molecular mechanisms of circPWWP2A on the inflammatory response. The inhibitory effect of miR-223-3p on its target NLRP3 was suppressed by circPWWP2A, which led to lung fibrosis. Our study found that circPWWP2A could adsorb miR-223-3p to regulate NLRP3 after silica stimulation in pulmonary fibrosis. And our results revealed that the circPWWP2A-miR-223-3p-NLRP3 axis was potentially instrumental in managing silica-induced inflammation and fibrosis. Previous studies have demonstrated that human umbilical cord mesenchymal stem cell-derived extracellular vesicles (hucMSC-EVs) exhibit anti-inflammatory and anti-fibrotic effects in multiple organs. However, the potential effectiveness of hucMSC-EVs against silicosis or the underlying mechanisms of their biological outcomes remains unclear. Therefore, we used 3D culture technology to extract hucMSC-EVs and observed their effects in macrophages and lung tissues, respectively. According to the EVmiRNA database, miR-223-3p was abundant in MSC-EVs. In addition, hucMSC-EVs may modulate lung function, reduce the secretion of inflammatory factors (NLRP3, IL-1β, IL-18 and cleaved Caspase-1) and attenuate the deposition of fibrosis-related factors (Collagen Ⅰ, Collagen Ⅲ, fibronectin and α-SMA). In vitro results evinced that hucMSC-EVs reduced the inflammatory response of macrophages and restricted the activation and proliferation of fibroblasts. Moreover, our study showed that hucMSCs-EVs acted as a mediator to transfer miR-223-3p to suppress circPWWP2A, thereby alleviating pulmonary fibrosis through the NLRP3 signaling pathway. These data may provide potentially novel strategies for investigating the pathogenesis of silicosis and developing novel treatments for this disease., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Yangqing Chenfei formula (YCF) has been demonstrated its clinical efficiency on silicosis patients. However, the effect of YCF against silicotic fibrosis and its mechanism remain unclear., Purpose: This study is aimed to investigate active compounds and molecular mechanism of YCF in treating silicosis., Method: YCF was orally administrated to silicosis rats induced by crystalline silica. The effective fraction of YCF and the compounds was isolated and identified by using macroporous resin and HPLC-MS, respectively. The targets and potential molecular mechanism of YCF against silicotic fibrosis were investigated through pharmacological network and RNA-sequencing analysis and in vitro-experimental validation., Results: YCF could remarkably improve the lung function and pathological changes of silicotic rats, reduce the aggregation of fibrocytes and deposition of ECM, such as collagen I, III, FN, and α-SMA, and suppress the TGF-β/Smad3 signaling. Furthermore, YCF6, the effective fraction derived from YCF, could significantly inhibit fibroblast activation induced by TGF-β. Then, 135 compounds were identified from YCF6 by using HPLC-MS, and Network pharmacology analysis predicted total 941 targets for these compounds. Moreover, 409 differentially expressed genes of fibroblast activation induced by TGF-β were identified. Then, integrated analysis of the 941 targets with 409 differentially expressed genes showed that YCF6 contains multiple compounds, such as tangeretin, L-Malic acid, 2-Monolinolein etc., which inhibits fibroblast activation probably by targeting different proteins, such as PIK3CA, AKT1, JAK2, STAT3, GSK3β, leading to regulate the signal network, such as PI3K/AKT signaling pathway, JAK/STAT signaling pathway, and Wnt signaling pathway. Finally, in vitro experiment indicated that tangeretin, the active compound contained in YCF6, could significantly inhibit TGF-β induced fibroblast activation. Moreover, YCF6 and tangeretin could markedly inhibit the activation of PI3K/AKT, JAK/STAT, and Wnt pathway., Conclusion: YCF contained multiple compounds and targeted various proteins that regulated the fibroblast activation, which might be the molecular mechanisms of it in treating silicosis., Competing Interests: Declaration of Competing Interest The authors definite that there are no known conflicts of interest concerned with this article., (Copyright © 2022 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

Silicosis caused by long-term inhalation of crystalline silica during occupational activities seriously threatens the health of occupational populations. Imbalances in T helper 1(Th1), Th2, Th17, and regulatory T cells (Tregs) promote the development of pulmonary silicosis. Exosomes and their contents, especially microRNAs (miRNAs), represent a new type of intercellular signal transmission mediator related to various diseases including pulmonary fibrosis. However, whether exosomal miRNAs can affect the progression of silicosis by regulating T cell differentiation remains to be determined. To test this hypothesis, we established a miR-125a-5p antagomir mouse model and examined changes in miR-125a-5p levels and T cell subtypes. We found that miR-125a-5p levels were increased in lung tissues and serum exosomes in the silica group at 7 days and 28 days. Downregulation of miR-125a-5p attenuated α-smooth muscle actin (α-SMA), collagen I, fibronectin, p-p65, and p-inhibitor of nuclear factor kappa B (NF-κB) kinase (IKK) protein expression, while tumor necrosis factor receptor-associated factor 6 (TRAF6) and p-inhibitor of κBα (IKBα) expression were increased. MiR-125a-5p anta-miR treatment contributes to the maintenance of Th1/Th2 balance during the progression of pulmonary fibrosis. Our findings indicated that knockdown miR-125a-5p could regulate T lymphocyte subsets and significantly reduce pulmonary fibrosis by targeting TRAF6., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Wu Yao reports financial support was provided by National Natural Science Foundation of China., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Circular RNAs (circRNAs) are emerging as novel regulators in the biological development of various diseases, but their expression profiles, functions and mechanisms in silicosis and pulmonary fibrosis remain largely unexplored. In this study, we constructed a mouse model of pulmonary fibrosis by intratracheal injection of silica particles and then performed transcriptome RNA sequencing of lung tissues. The results showed that 78 circRNAs, 39 miRNAs and 262 mRNAs were differentially expressed. Among them, five circRNAs, three miRNAs and four mRNAs were further selected, and their abnormal expression was verified in mouse fibrotic lung tissues by RT-qPCR assay. The circRNA-associated ceRNA network including 206 ceRNA triplets was constructed based on abnormally expressed circRNAs, miRNAs and mRNAs, and miR-199b-5p, miR-296-5p and miR-708-5p were identified as hub miRNAs connected to circRNAs and mRNAs. Subsequently, GO and KEGG pathway enrichment analyses were performed to detect the potential roles of differentially expressed mRNAs in pulmonary fibrosis, which were mainly involved in immune response, Th17 cell differentiation, NF-κB signaling pathway and PI3K-Akt signaling pathway. Furthermore, we identified that hsa&#95;circ&#95;0006916 was up-regulated in pulmonary fibrosis. To characterize the potential role of hsa&#95;circ&#95;0006916, we transfected siRNA targeting hsa&#95;circ&#95;0006916 into alveolar macrophages and found that knockdown of hsa&#95;circ&#95;0006916 significantly increased the expression levels of M1 molecules IL-1β and TNF-α and reduced the expression level of M2 molecule TGF-β1, indicating that hsa&#95;circ&#95;0006916 may play an important role in the activation of M1-M2 polarization effect in macrophages. Our results provided important evidence on the possible contribution of these abnormal circRNAs to the development of silicosis and pulmonary fibrosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Epithelial-mesenchymal transdifferentiation of alveolar type Ⅱ epithelial cells is a vital source of pulmonary myofibroblasts, and myofibroblasts formation is recognized as an important phase in the pathological process of silicosis. miR-30c-5p has been determined to be relevant in the activation of the epithelial-mesenchymal transition (EMT) in numerous disease processes. However, elucidating the role played by miR-30c-5p in the silicosis-associated EMT process remains a great challenge. In this work, based on the establishment of mouse silicosis and A549 cells EMT models, miR-30c-5p was interfered with in vivo and in vitro models to reveal its effects on EMT and autophagy. Moreover, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), connective tissue growth factor (CTGF), autophagy-related gene 5 (ATG5), and autophagy were further interfered with in the A549 cells models to uncover the possible molecular mechanism through which miR-30c-5p inhibits silicosis associated EMT. The results demonstrated the targeted binding of miR-30c-5p to CTGF, ATG5, and MALAT1, and showed that miR-30c-5p could prevent EMT in lung epithelial cells by acting on CTGF and ATG5-associated autophagy, thereby inhibiting the silicosis fibrosis process. Furthermore, we also found that lncRNA MALAT1 might competitively absorb miR-30c-5p and affect the EMT of lung epithelial cells. In a word, interfering with miR-30c-5p and its related molecules (MALAT1, CTGF, and ATG5-associated autophagy) may provide a reference point for the application of silicosis intervention-related targets., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: Pneumoconiosis, encompassing coal workers' pneumoconiosis (CWP), silicosis and asbestosis, is one of the most common occupational diseases in China. Previous studies revealed significant associations between genetic variations and pneumoconiosis risk among individuals in different countries. With the known variability of genetic makeup between ethnicities, susceptibility to pneumoconiosis due to genetic differences is likely to be ethnicity-specific. The present review aimed at providing a comprehensive overview on the association between genetic polymorphisms and susceptibility of pneumoconiosis, specifically among people in China., Methods: The literature search was performed in seven English and Chinese databases using keywords related to the review aim. An appraisal of the methodological quality of the included studies was conducted using the assessment tool derived from the Strengthening the Reporting of Genetic Association Studies (STREGA) statement., Results: Forty-five studies were included in this review. Genotypes of specific genes which are associated with the risk of CWP, silicosis and asbestosis were reported. Our findings showed that genes encoding inflammatory cytokines have been examined extensively, and they demonstrated an association between these genes and pneumoconiosis risk. Gene-environment interactions in pneumoconiosis susceptibility were also reported by a number of studies., Conclusions: This review summarised the evidence demonstrating the association between genetic polymorphisms and pneumoconiosis susceptibility among people in China, and that various genotypes could modify their risk to develop pneumoconiosis. The findings prompt that identification of individuals at high pneumoconiosis risk through genetic screening and strategies limiting their exposure to dust could be a potential strategy for the control of this occupational disease in China., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Millions of patients suffer from silicosis, but it remains an uncurable disease due to its unclear pathogenic mechanisms. Though the Nlrp3 inflammasome is involved in silicosis pathogenesis, inhibition of its classic downstream factors, Caspase-1 and Gsdmd, fails to block pyroptosis and cytokine release. To clarify the molecular mechanism of silicosis pathogenesis for new therapy, we examined samples from silicosis patients and genetic mouse models. We discovered an alternative pyroptotic pathway which requires cleavage of Gsdme by Caspases-3/8 in addition to Caspase-1/Gsdmd. Consistently, Gsdmd-/-Gsdme-/- mice showed markedly attenuated silicosis pathology, and Gsdmd-/-Gsdme-/- macrophages were resistant to silica-induced pyroptosis. Furthermore, we found that in addition to Caspase 1, Caspase-8 cleaved IL-1β in silicosis, explaining why Caspase-1-/- mice also suffered from silicosis. Finally, we found that inhibitors of Caspase-1, -3, -8 or an FDA approved drug, dimethyl fumarate, could dramatically alleviate silicosis pathology through blocking cleavage of Gsdmd and Gsdme. This study highlights that Caspase-1/Gsdmd and Caspase-3/8/Gsdme-dependent pyroptosis is essential for the development of silicosis, implicating new potential targets and drug for silicosis treatment., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Kang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: Silicosis is a pneumoconiosis characterized by fibrosis of the lung parenchyma caused by inhalation of silica particles. Genetic factors might play a role in the severity silicosis. We sought to evaluate the influence of polymorphisms in the ACE, FAS, FASLG, NOS2, IL1RN, FAM13A, TGFB1, and TNF genes on the severity of silicosis., Methods: Nine polymorphisms were genotyped by PCR in a sample of 143 patients with silicosis in the state of Rio de Janeiro, Brazil., Results: Fifty-seven patients (40%) were classified as having simple silicosis and 86 (60%) were classified as having complicated silicosis. The TT genotype of rs1800469 in the TGFB1 gene showed a protective effect for complicated silicosis (OR = 0.35; 95% CI, 0.14-0.92; p = 0.028) when compared with the other two genotypes (CC+CT). The polymorphic T allele of rs763110 in the FASLG gene (OR = 0.56; 95% CI, 0.31-0.99; p = 0.047), as well as a dominant model for the T allele (TT+CT: OR = 0.37; 95% CI, 0.15-0.96; p = 0.037), also showed a protective effect. When patients with simple silicosis despite having been exposed to silica for a longer time (> 44,229 hours) were compared with patients with complicated silicosis despite having been exposed to silica for a shorter time, the T allele of rs763110 in the FASLG gene (OR = 0.20; 95% CI, 0.08-0.48; p < 0.0001), as well as dominant and recessive models (OR = 0.06; 95% CI, 0.00-0.49; p = 0.01 and OR = 0.22; 95% CI, 0.06-0.77; p = 0.014, respectively), showed a protective effect against the severity of silicosis., Conclusions: It appears that rs1800469 polymorphisms in the TGFB1 gene and rs763110 polymorphisms in the FASLG gene are involved in the severity of silicosis. Given the lack of studies relating genetic polymorphisms to the severity of silicosis, these results should be replicated in other populations.

Silicosis is one of the most important occupational diseases worldwide, caused by inhalation of silica particles or free crystalline silicon dioxide. As a disease with high mortality, it has no effective treatment and new therapeutic targets are urgently needed. Recent studies have identified FCER1A, encoding α-subunit of the immunoglobulin E (IgE) receptor FcεRI, as a candidate gene involved in the biological pathways leading to respiratory symptoms. FcεRI is known to be important in allergic asthma, but its role in silicosis remains unclear. In this study, serum IgE concentrations and FcεRI expression were assessed in pneumoconiosis patients and silica-exposed mice. The role of FcεRI was explored in a silica-induced mouse model using wild-type and FcεRI-deficient mice. The results showed that serum IgE concentrations were significantly elevated in both pneumoconiosis patients and mice exposed to silica compared with controls. The mRNA and protein expression of FcεRI were also significantly increased in the lung tissue of patients and silica-exposed mice. FcεRI deficiency significantly attenuated the changes in lung function caused by silica exposure. Silica-induced elevations of IL-1β, IL-6, and TNF-α were significantly attenuated in the lung tissue and bronchoalveolar lavage fluid (BALF) of FcεRI-deficient mice compared with wild-type controls. Additionally, FcεRI-deficient mice showed a significantly lower score of pulmonary fibrosis than wild-type mice following exposure to silica, with significantly lower hydroxyproline content and expression of fibrotic genes Col1a1 and Fn1. Immunofluorescent staining suggested FcεRI mainly on mast cells. Mast cell degranulation took place after silica exposure, as shown by increased serum histamine levels and β-hexosaminidase activity, which were significantly reduced in FcεRI-deficient mice compared with wild-type controls. Together, these data showed that FcεRI deficiency had a significant protective effect against silica-induced pulmonary inflammation and fibrosis. Our findings provide new insights into the pathophysiological mechanisms of silica-induced pulmonary fibrosis and a potential target for the treatment of silicosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

In this study, we aimed to reveal the association between circRNA-related single nucleotide polymorphisms (SNPs) with the susceptibility of silicosis. To achieve this goal, a silicosis-related GWAS was constructed to select the candidate SNPs, and circBase database was utilized to select the promising SNPs which may locate on circRNAs. In addition, the eQTL analysis between the SNPs and located genes was performed to select the candidate SNPs. Finally, the association between candidate SNPs with the susceptibility of silicosis was validated. As a result, we firstly selected 10,922 SNPs with P < 1 × 10 -3 through the silicosis-related GWAS. Among which, 1,752 SNPs were identified that may locate on 2,660 circRNAs. After the MAF evaluation and the sequences checking, we obtained 94 SNPs and related 105 circRNAs. EQTL analysis indicated that 7 circRNA-SNPs might regulate the expression of located genes. Subsequently, a strong association was found between variant A of rs17115143 and silicosis risk in the validation stage (OR= 1.68, P = 0.032). Combination of the GWAS data and Taqman genotyping data also revealed a strong association between rs17115143 and silicosis risk in both dominant and additive models (dom: OR= 1.96, P = 3.98 × 10 -4 ; add: OR= 1.40, P = 3.06 × 10 -4 ). In conclusion, the variant A allele of circRNA-SNP rs17115143 could be a risk factor in the progression of silicosis. And related 6 circRNAs may function as novel biomarkers for the diagnostic of silicosis. Further researches to explore the biological mechanisms of rs17115143 related 6 circRNAs in the regulation of silicosis are warranted., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Silicosis is one of the most serious occupational diseases with the main feature of inflammatory cell infiltration, fibroblasts activation, and large deposition of extracellular matrix in the lung. Increasing evidence indicates that macrophage-derived exosomes may play an important role in the development of silicosis by transferring their loaded microRNAs (miRNAs). Hence we carried out high-throughput sequencing to identify the expression of exosomal miRNA from macrophages exposed to silica or not in the previous study. Then we verified that miR-7219-3p was significantly up-regulated in macrophages and their exosomes after silica-exposure, as well as in the silicotic mice model by qRT-PCR, subsequent experiments confirmed that the increase of miR-7219-3p facilitated fibroblast to myofibroblast trans-differentiation (FMT), as well as cell proliferation and migration. Spouty1 (SPRY1), which served as a negative modulator of the Ras/ERK/MAPK signaling pathway, was verified as the target gene of miR-7219-3p, the knockdown or over-expression of SPRY1 apparently promoted or inhibited FMT via the Ras/ERK/MAPK signaling pathway. Furthermore, the inhibition of exosomal miR-7219-3p partially suppressed FMT and silica-induced pulmonary fibrosis in vitro and in vivo. In brief, our results demonstrated that exosomal miR-7219-3p played an important role in FMT and might be a novel therapeutic target of silicosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Silicosis is the most prevalent and fatal occupational disease with no effective therapeutics, and currently used drugs cannot reverse the disease progress. Worse still, there are still challenges to be addressed to fully decipher the intricated pathogenesis. Thus, specifying the essential mechanisms and targets in silicosis progression then exploring anti-silicosis pharmacuticals are desperately needed. In this work, multi-omics atlas was constructed to depict the pivotal abnormalities of silicosis and develop targeted agents. By utilizing an unbiased and time-resolved analysis of the transcriptome, proteome and phosphoproteome of a silicosis mouse model, we have verified the significant differences in transcript, protein, kinase activity and signaling pathway level during silicosis progression, in which the importance of essential biological processes such as macrophage activation, chemotaxis, immune cell recruitment and chronic inflammation were emphasized. Notably, the phosphorylation of EGFR (p-EGFR) and SYK (p-SYK) were identified as potential therapeutic targets in the progression of silicosis. To inhibit and validate these targets, we tested fostamatinib (targeting SYK) and Gefitinib (targeting EGFR), and both drugs effectively ameliorated pulmonary dysfunction and inhibited the progression of inflammation and fibrosis. Overall, our drug discovery with multi-omics approach provides novel and viable therapeutic strategies for the treatment of silicosis., (© 2022. The Author(s).)

Existing studies reported that some circular RNAs (circRNAs) play vital roles in the development of pulmonary fibrosis. However, few studies explored the biomarker potential of circRNAs for pulmonary fibrosis based on population data. Therefore, we aimed to identify peripheral blood circRNAs as potential biomarkers for diagnosing silicosis and idiopathic pulmonary fibrosis (IPF). In brief, an RNA-seq screening based on 4 silicosis cases and 4 controls was initially performed. Differentially expressed circRNAs were combined with the human serum circRNA dataset to identify overlapping serum-detectable circRNAs, followed by validation using the GEO dataset (3 IPF cases and 3 controls) and subsequent qRT-PCR, including 84 additional individuals. Following the above steps, 243 differentially expressed circRNAs were identified during the screening stage, with fold changes ≥ 1.5 and P < 0.05. Of note, the human serum circRNA dataset encompassed 28 of 243 circRNAs. GEO (GSE102660) validation revealed two highly expressed circRNAs (P < 0.05) in the IPF case group. Furthermore, at the enlarged sample validation stage, hsa&#95;circ&#95;0058493 was highly expressed in both silicosis and IPF cases (silicosis: P = 1.16 × 10 -6 ; IPF: P = 7.46 × 10 -5 ). Additionally, hsa&#95;circ&#95;0058493 expression was significantly increased in MRC-5 cells upon TGF-β1 treatment, while hsa&#95;circ&#95;0058493 knockdown inhibited the expression of fibrotic molecules by affecting the epithelial-mesenchymal transition process. These shreds of evidence indicated that hsa&#95;circ&#95;0058493 might serve as a novel biomarker for diagnosing silicosis and IPF., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Silicosis is a systemic disease characterized by diffuse fibrosis of lung tissue. However, its pathogenesis has not been fully elucidated. Previous studies have demonstrated that there is a close relationship between EMT and pulmonary fibrosis. However, LncRNA XIST and miR-101-3p regulate the expression of ZEB1 which is a key transcription factor in the process of EMT through competitive endogenous RNA, thus affecting the process of EMT has not been reported. In this work, an experimental silicosis mouse model and cell model of TGF-β1 stimulated lung epithelial cells (A549) for 48 h are established to investigate the biological effects of LncRNA XIST/ miR-101-3p/ZEB1 axis in the EMT process. The results reveal that LncRNA XIST and ZEB1 are up-regulated while the miR-101-3p expression is down-regulated in vivo and vitro models. Furthermore, the knockdown of LncRNA XIST prevents the EMT process and the inhibition of miR-101-3p markedly promotes EMT stimulated by TGF-β1. Moreover, the results also illustrate that LncRNA XIST is mainly localized in the cytoplasm used FISH and possesses binding site with miR-101-3p which was identified as the target of ZEB1 used bioinformatics prediction website and Dual-luciferase reporter assay. The above demonstrated that LncRNA-XIST regulates ZEB1 by directly sponging miR-101-3p. To sum up, we uncovered that the up-regulated LncRNA XIST can modulate miR-101-3p and then up-regulate the expression of ZEB1, thus promoting the EMT process of alveolar epithelial cells in the process of silicosis-related pulmonary fibrosis EMT. Our study provides a new research idea for related targets of silicosis treatment., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The main clinical manifestations are pulmonary fibrosis, silicosis, is one of the most common types of pneumoconiosis, and its pathogenesis is still unclear. The proliferation and transdifferentiation of fibroblasts are considered to be the key link leading to pulmonary fibrosis. Type II alveolar epithelial cells can be transformed into lung fibroblasts through epithelial-mesenchymal transition (EMT) to promote lung fibrosis. Involved in the EMT process of a variety of cancers, lncRNA UCA1 (UCA1) has been shown to competitively adsorb miR-204-5p, and play an effect on the downstream target gene E-box binding zinc finger protein 1 (ZEB1), thereby promoting EMT to facilitate the invasion and migration of cancer cells. This is an important potential intervention target that affects the process of EMT, but it has not been reported in the study of EMT related to silicosis. Therefore, this study established a SiO 2 dust-treated mouse silicosis model and an in vitro EMT model of A549 cells to observe the changes and effects of UCA1 and miR-204-5p, and intervene on the two respectively. The results showed that the EMT process existed in the aforementioned models, while UCA1 was upregulated in the in vitro model. Double luciferase reporter assay demonstrated the targeted binding of UCA1 and miR-204-5p. Silencing UCA1 can up-regulate the expression of miR-204-5p and reduce the level of ZEB1, thus inhibiting EMT process, while intervention of miR-204-5p can change the level of ZEB1 and regulate EMT. Therefore, UCA1 may release its target gene ZEB1 through competitive adsorption of miR-204-5p to regulate EMT process., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Silicosis is an occupational disease caused by inhalation of silica dust, which is hallmarked by progressive pulmonary fibrosis associated with poor prognosis. Wnt/β-catenin signaling is implicated in the development of fibrosis and is a therapeutic target for fibrotic diseases. Previous clinical studies of patients with pneumoconiosis, including silicosis, revealed an increased concentration of circulating WNT3A and DKK1 proteins and inflammatory cells in bronchoalveolar lavage compared with healthy subjects. The present study evaluated the effects of adenovirus-mediated transduction of Dickkopf-1 ( Dkk1 ), a Wnt/β-catenin signaling inhibitor, on the development of pulmonary silicosis in mice. Consistent with previous human clinical studies, our experimental studies in mice demonstrated an aberrant Wnt/β-catenin signaling activity coinciding with increased Wnt3a and Dkk1 proteins and inflammation in lungs of silica-induced silicosis mice compared with controls. Intratracheal delivery of adenovirus expressing murine Dkk1 (AdDkk1) inhibited Wnt/β-catenin activity in mouse lungs. The adenovirus-mediated Dkk1 gene transduction demonstrated the potential to prevent silicosis development and ameliorate silica-induced lung fibrogenesis in mice, accompanied by the reduced expression of epithelia--mesenchymal transition markers and deposition of extracellular matrix proteins compared with mice treated with "null" adenoviral vector. Mechanistically, AdDkk1 is able to attenuate the lung silicosis by inhibiting a silica-induced spike in TGF-β/Smad signaling. In addition, the forced expression of Dkk1 suppressed silica-induced epithelial cell proliferation in polarized human bronchial epithelial cells. This study provides insight into the underlying role of Wnt/β-catenin signaling in promoting the pathogenesis of silicosis and is proof-of-concept that targeting Wnt/β-catenin signaling by Dkk1 gene transduction may be an alternative approach in the prevention and treatment of silicosis lung disease.

Background: Silicosis is a systemic disease characterized by persistent inflammation and incurable pulmonary fibrosis. Although great effort has been made to understand the pathogenesis of the disease, molecular mechanism underlying silicosis is not fully elucidated. This study was aimed to explore proteomic and transcriptomic changes in rat model of silicosis., Methods: Twenty male Wistar rats were randomly divided into two groups with 10 rats in each group. Rats in the model group were intratracheally instilled with 50 mg/mL silicon dioxide (1 mL per rat) and rats in the control group were treated with 1.0 mL saline (1 mL per rat). Twenty-eight days later, transcriptomic analysis by microarray and tandem mass tags (TMT)-based proteomic analysis were performed to reveal the expression of mRNAs and proteins in lung tissues. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were applied to analyze the altered genes and proteins. The integrated analysis was performed between transcriptome and proteome. The data were further verified by RT-qPCR and parallel reaction monitoring (PRM)., Results: In total, 1769 differentially expressed genes (DEGs) and 650 differentially expressed proteins (DEPs) were identified between the silicosis model and control groups. The integrated analysis showed 250 DEPs were correlated to the corresponding DEGs (cor-DEPs-DEGs), which were mainly enriched in phagosome, leukocyte transendothelial migration, complement and coagulation cascades and cellular adhesion molecule (CAM). These pathways are interrelated and converged at common points to produce an effect. GM2a, CHI3L1, LCN2 and GNAI1 are involved in the extracellular matrix (ECM) and inflammation contributing to fibrosis., Conclusion: Our comprehensive transcriptome and proteome data provide new insights into the mechanisms of silicosis and helpful information for more targeted prevention and treatment of silicosis., (© 2021. The Author(s).)

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.

Silicosis, induced by inhaling silica particles in workplaces, is one of the most common occupational diseases. The prognosis of silicosis and its consequent fibrosis is extremely poor due to limited treatment modalities and lack of understanding of the disease mechanisms. In this study, a Wistar rat model for silicosis fibrosis was established by intratracheal instillation of silica (0, 50, 100 and 200 mg/mL, 1 mL) with the evidence of Hematoxylin and Eosin (HE) and Masson staining and the expressions of inflammatory and fibrotic proteins of rats' lung tissues. RNA of lung tissues of rats exposed to 200 mg/mL silica particles and normal saline for 14 d and 28 d was extracted and sequenced to detect differentially expressed genes (DEGs) and to identify silicosis fibrosis-associated modules and hub genes by Weighted gene co-expression network analysis (WGCNA). Predictions of gene functions and signaling pathways were conducted using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. In this study, it has been demonstrated the promising role of the Hippo signaling pathway in silicosis fibrosis, which will be conducive to elucidating the specific mechanism of pulmonary fibrosis induced by silica and to determining molecular initiating event (MIE) and adverse outcome pathway (AOP) of silicosis fibrosis.

Objective: To explore the difference of methylation of circRNA related m6A in early inflammation of silicosis and to elucidate the underlying molecular mechanism of circRNA involved in the process of silicosis. Methods: The activation markers of macrophages were detected by Western blotting (WB) in THP-1-derived macrophages. The cell viability was detected with CCK8, by which the stimulation concentration and time of silica were determined. The methylation of total RNA was determined by colorimetry, and the expression of RNA m6A methylase, demethylase and reading protein were detected by Western blotting in mouse model of silicosis. The differential expression of m6A modified circRNA in lung tissues form silicosis and control mice was obtained through Arraystar m6A circRNA epigenetic transcriptome Chip and verified by RT-PCR. Results: The concentration of SiO(2) at 50 μg/cm(2) had the most significant effect on the activation markers and activity of macrophages. Compared with the control group, SiO(2) increased the total RNA m6A level of macrophages, and there were significant differences in the expression of methylase METTL3 and reading protein YTDHF3. High throughput sequencing analysis showed that compared with the control group, the methylation levels of 132 circRNA m6A in the lung of silicosis model mice were increased, while the methylation levels of 296 circRNA m6A were decreased, and then the target circSLC2A13 was screened based on the basic expression. Further verification showed that SiO(2) significantly increased the expression of circSLC2A13 and m6A modification in macrophages. Conclusion: The methylation of circRNA m6A is involved in the activation of macrophages in early inflammation of silicosis.

Objective: To investigate the expression of lipoic acid synthase gene ( LIAS ) and nuclear factor-erythroid 2-related factor 2 gene ( NRF2 ) in peripheral blood mononuclear cells (PBMCs) from patients with silicosis and their correlation with silicosis. Methods: A total of 45 healthy controls and 107 patients with silicosis were randomly selected in this study in May 2019. PBMCs were isolated from peripheral blood and NRF2 protein expression was detected by immunofluorescence. The mRNA levels of LIAS and NRF2 in PBMCs were determined by real-time PCR. The dose-response relationship beween LIAS and NRF2 mRNA expression levels and their association with silicosis were analyzed by restricted cubic spline (RCS) and logistic regression. Results: Compared with the control group, the number of monocytes in the case group was significantly increased, and the forced expiratory volume in the first second (FEV(1.0)) decreased, the difference was statistically significant ( P <0.05) . The positive expression rate of NRF2 in PBMCs of silicosis patients in stage Ⅰ group was significantly higher than that in the control group, and the positive expression rate of NRF2 in silicosis patients in stageⅡ and Ⅲ groups was lower than that in silicosis patients in control group and stage Ⅰ group ( P <0.01) . Results of RCS showed that there was a linear dose-response relationship between LIAS and NRF2 mRNA expression (overall correlation test, χ(2)=213.710, P <0.01; non-linear test, χ(2)=1.340, P =0.511) . There was a positive correlation between mRNA expression of LIAS and that of NRF2 ( r =0.651, P <0.01) . The results of multivariate analysis showed that LIAS and NRF2 were increased the risk of incidence in silicosis patients with stageⅠ ( OR =11.184, 4.332, P <0.05) and NRF2 was the protective factor in silicosis patients with stage Ⅱ and Ⅲ ( OR =0.225, 0.208, P <0.05) after adjusting for potential confounding factors including age, education level, BMI and smoking. Conclusion: There is a linear dose-response relationship between the expression of LIAS and NRF2 mRNA in PBMCs of silicosis patients, LIAS and NRF2 are involved in the pathogenesis of silicosis.

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