Association of smoking cessation with airflow obstruction in workers with silicosis: A cohort study.

BACKGROUND: Studies in general population reported a positive association between tobacco smoking and airflow obstruction (AFO), a hallmark of chronic obstructive pulmonary disease (COPD). However, this attempt was less addressed in silica dust-exposed workers. METHODS: This retrospective cohort study consisted of 4481 silicotic workers attending the Pneumoconiosis Clinic during 1981-2019. The lifelong work history and smoking habits of these workers were extracted from medical records. Spirometry was carried out at the diagnosis of silicosis (n = 4177) and reperformed after an average of 9.4 years of follow-up (n = 2648). AFO was defined as forced expiratory volume in one second (FEV1)/force vital capacity (FVC) less than lower limit of normal (LLN). The association of AFO with smoking status was determined using multivariate logistics regression, and the effect of smoking cessation on the development of AFO was evaluated Cox regression. RESULTS: Smoking was significantly associated with AFO (current smokers: OR = 1.92, 95% CI 1.51-2.44; former smokers: OR = 2.09, 95% CI 1.65-2.66). The risk of AFO significantly increased in the first 3 years of quitting smoking (OR = 1.23, 95% CI 1.02-1.47) but decreased afterwards with increasing years of cessation. Smoking cessation reduced the risk of developing AFO no matter before or after the confirmation of silicosis (pre-silicosis cessation: HR = 0.58, 95% CI 0.46-0.74; post-silicosis cessation: HR = 0.62, 95% CI 0.48-0.79). CONCLUSIONS: Smoking cessation significantly reduced the risk of AFO in the workers with silicosis, although the health benefit was not observed until 3 years of abstinence. These findings highlight the importance of early and long-term smoking cessation among silicotic or silica dust-exposed workers.

miR-455-3p regulates lymphangiogenesis in silicosis by regulating VEGF-C/VEGFR3.

Silicosis is a disease characterized by lung inflammation and fibrosis caused by long-term inhalation of free silicon dioxide (SiO2). Recent studies have found that a large number of lymphatic hyperplasia occurs during the occurrence and development of silicosis. miRNAs play an important role in lymphangiogenesis. However, the regulation and mechanism of miRNAs on lymphangiogenesis in silicosis remain unclear. In this study, lymphangiogenesis was observed in silicosis rats, and VEGF-C-targeted miRNAs were screened, and the effect of miRNAs on the formation of human lymphatic endothelial cells (HLECs) tubular structure was investigated in vitro. The results showed that SiO2 promoted the expressions of Collagen Ι and α-SMA, TNF-α, IL-6 and VEGF-C increased first and then decreased, and promoted the formation of lymphatic vessels. Bioinformatics methods screened miR-455-3p for targeted binding to VEGF-C, and dual luciferase reporter genes confirmed VEGF-C as the target gene of miR-455-3p, and miR-455-3p was down-regulated in the lung tissue of silicosis rats. Transfection of miR-455-3p Inhibitors down-regulated the expression level of miR-455-3p and up-regulated the expression levels of VEGF-C and VEGFR-3 in HLECs, enhanced migration ability and increased tube formation. Transfection of miR-455-3p Mimics showed an opposite trend. These results suggest that miR-455-3p further regulates the tubular structure formation of HLECs by regulating VEGF-C/VEGFR3. Therefore, targeting miR-455-3p may provide a new therapeutic strategy for SiO2-induced silicosis injury.

Low-Level Respirable Crystalline Silica and Silicosis: Long-Term Follow-Up of Vermont Granite Workers.

The lifetime risk of silicosis associated with low-level occupational exposure to respirable crystalline silica remains unclear because most previous radiographic studies included workers with varying exposure concentrations and durations. This study assessed the prevalence of silicosis after lengthy exposure to respirable crystalline silica at levels ≤ 0.10 mg/m3. Vermont granite workers employed any time during 1979-1987 were traced and chest radiographs were obtained for 356 who were alive in 2017 and residing in Vermont. Work history, smoking habits and respiratory symptoms were obtained by interview, and exposure was estimated using a previously developed job-exposure matrix. Associations between radiographic findings, exposure, and respiratory symptoms were assessed by ANOVA, chi-square tests and binary regression. Fourteen workers (3.9%) had radiographic evidence of silicosis, and all had been employed ≥30 years. They were more likely to have been stone cutters or carvers and their average exposure concentrations and cumulative exposures to respirable crystalline silica were significantly higher than workers with similar durations of employment and no classifiable parenchymal abnormalities. This provides direct evidence that workers with long-term exposure to low-level respirable crystalline silica (≤0.10 mg/m3) are at risk of developing silicosis.

Update on Silicosis.

Although silicosis has been an established disease with a recognized cause for more than 100 years, many workers continue to be exposed to silica and new outbreaks of disease continue to occur. This article describes some of the well-established and new exposures, including denim sandblasting, artificial stone cutting, and some forms of "coal worker's pneumoconiosis." The authors review the imaging and pathology of acute silicosis (silicoproteinosis), simple silicosis, and progressive massive fibrosis and summarize known and putative associations of silica exposure, including tuberculosis, lung cancer, connective tissue disease (especially systemic sclerosis), and vasculitis.

Nano-enabled delivery of diosgenin and emodin ameliorates respirable silica dust-induced pulmonary fibrosis silicosis in rats.

Oxidative stress and inflammation play a fundamental role in the beginning and advancement of silicosis. Hence, questing active phytocompounds (APCs) with anti-oxidative and anti-inflammatory properties such as diosgenin (DG) and emodin (ED) can be a therapeutic intervention targeting silica-induced pulmonary inflammation and fibrosis. Hydrophobicity and low bioavailability are the barriers that restrict the therapeutic efficacy of DG and ED against pulmonary defects. Encapsulating these APCs in polymeric nanoparticles can overcome this limitation. The present study has thus explored the anti-inflammatory and anti-fibrotic effects of polylactic-co-glycolic acid (PLGA) nanoparticles (NPs) individually loaded with DG (DGn) or ED (EDn) and in combine DG+ED [(DG+ED)n] in respirable silica dust (RSD)-induced pulmonary fibrosis silicosis rat model. Our study found that individual and combined NPs revealed physiochemical characteristics appropriate for IV administration with sustained-drug release purposes. Physiological evaluations of RSD-induced silicosis rats suggested that no treatment could improve the body weight. Still, they reduced the lung coefficient by maintaining lung moisture. Only (DG+ED)n significantly cleared free lung silica. All interventions were found to attribute the increased per cent cell viability in BALF, reduce cytotoxicity via minimizing LDH levels, and balance the oxidant-antioxidant status in silicotic rats. The expression of inflammatory cytokines (TNF-α, IL-1ß, IL-6, MCP-1, and TGF-ß1) were efficiently down-regulated with NPs interventions compared to pure (DG+ED) treatment. All drug treatments significantly declined, the 8-HdG and HYP productions indicate that RSD-induced oxidative DNA damage and collagen deposition were successfully repaired. Moreover, histopathological investigations proposed that individual or combined drugs NPs interventions could decrease the fibrosis and alveolitis grades in RSD-induced silicosis rats. However, (DG+ED)n intervention significantly inhibited pulmonary fibrosis and alveolitis compared to pure (DG+ED) treatment. In conclusion, the RSD can induce oxidative stress and inflammation in rats, producing reactive oxygen species (ROS)-mediated cytotoxicity to pulmonary cells and leading to silicosis development. The IV administration of combined NP suppressed lung inflammation and collagen formation by maintaining oxidant-antioxidant status and effectively interrupting the fibrosis-silicosis progression. These results may be attributed to the improved bioavailability of DG and ED through their combined nano-encapsulation-mediated targeted drug delivery.

Differential regulation of lung homeostasis and silicosis by the TAM receptors MerTk and Axl.

Introduction: TAM receptor-mediated efferocytosis plays an important function in immune regulation and may contribute to antigen tolerance in the lungs, a site with continuous cellular turnover and generation of apoptotic cells. Some studies have identified failures in efferocytosis as a common driver of inflammation and tissue destruction in lung diseases. Our study is the first to characterize the in vivo function of the TAM receptors, Axl and MerTk, in the innate immune cell compartment, cytokine and chemokine production, as well as the alveolar macrophage (AM) phenotype in different settings in the airways and lung parenchyma. Methods: We employed MerTk and Axl defective mice to induce acute silicosis by a single exposure to crystalline silica particles (20 mg/50 µL). Although both mRNA levels of Axl and MerTk receptors were constitutively expressed by lung cells and isolated AMs, we found that MerTk was critical for maintaining lung homeostasis, whereas Axl played a role in the regulation of silica-induced inflammation. Our findings imply that MerTk and Axl differently modulated inflammatory tone via AM and neutrophil recruitment, phenotype and function by flow cytometry, and TGF-ß and CXCL1 protein levels, respectively. Finally, Axl expression was upregulated in both MerTk-/- and WT AMs, confirming its importance during inflammation. Conclusion: This study provides strong evidence that MerTk and Axl are specialized to orchestrate apoptotic cell clearance across different circumstances and may have important implications for the understanding of pulmonary inflammatory disorders as well as for the development of new approaches to therapy.

Simvastatin attenuates silica-induced pulmonary inflammation and fibrosis in rats via the AMPK-NOX pathway.

BACKGROUND: Simvastatin (Sim), a hydroxy-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, has been widely used in prevention and treatment of cardiovascular diseases. Studies have suggested that Sim exerts anti-fibrotic effects by interfering fibroblast proliferation and collagen synthesis. This study was to determine whether Sim could alleviate silica-induced pulmonary fibrosis and explore the underlying mechanisms. METHODS: The rat model of silicosis was established by the tracheal perfusion method and treated with Sim (5 or 10 mg/kg), AICAR (an AMPK agonist), and apocynin (a NOX inhibitor) for 28 days. Lung tissues were collected for further analyses including pathological histology, inflammatory response, oxidative stress, epithelial mesenchymal transformation (EMT), and the AMPK-NOX pathway. RESULTS: Sim significantly reduced silica-induced pulmonary inflammation and fibrosis at 28 days after administration. Sim could reduce the levels of interleukin (IL)-1ß, IL-6, tumor necrosis factor-α and transforming growth factor-ß1 in lung tissues. The expressions of hydroxyproline, α-SMA and vimentin were down-regulated, while E-cad was increased in Sim-treated rats. In addition, NOX4, p22pox, p40phox, p-p47phox/p47phox expressions and ROS levels were all increased, whereas p-AMPK/AMPK was decreased in silica-induced rats. Sim or AICAR treatment could notably reverse the decrease of AMPK activity and increase of NOX activity induced by silica. Apocynin treatment exhibited similar protective effects to Sim, including down-regulating of oxidative stress and inhibition of the EMT process and inflammatory reactions. CONCLUSIONS: Sim attenuates silica-induced pulmonary inflammation and fibrosis by downregulating EMT and oxidative stress through the AMPK-NOX pathway.

Bioinformatics-based dynamics of cuproptosis -related indicators in experimental silicosis.

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.

Latent tuberculosis infection and infection-associated risk factors for miner workers with silicosis in eastern China.

OBJECTIVES: Silicosis people are at high risk of developing pulmonary tuberculosis. Whether silica exposure increases the likelihood of latent tuberculosis infection (LTBI) was not well understood, and potential factors involved in LTBI risk among silicosis people were not evaluated before. Thus, LTBI among silicosis people and potential risk factors for LTBI among silicosis people were evaluated in this study. METHODS: A cross-sectional study was undertaken for 130 miner workers with silicosis. The QFT-GIT was performed for LTBI detection. RESULTS: The LTBI was high to 31.6% (36/114) for silicosis participants, and 13.1% (13/99) had a history of tuberculosis. Drinking was associated with LTBI risk (OR = 6.92, 95%CI, 1.47-32.66, P = 0.015). Meanwhile, tunneling work was associated with an increased risk of LTBI compared with other mining occupations (OR = 3.91,95%CI,1.20-12.70, P = 0.024). CONCLUSIONS: The LTBI rate of silicosis participants was high and more than 10% had a history of tuberculosis. Drinking alcohol and tunneling were independent risk factors for LTBI in silicosis participants.

[Clinical characteristics and follow-up analysis of 63 cases of silicosis complicated with cavity-pulmonary tuberculosis].

Objective: To investigate the clinical characteristics and prognosis of silicosis complicated with cavity-pulmonary tuberculosis. Methods: The clinical data of 63 patients with silicosis complicated with cavity-pulmonary tuberculosis (group A) and silicosis patients (group B) admitted to Yantaishan Hospital from July 2018 to July 2022 were collected and analyzed. Results: Patients in group A were all male, and the common symptoms were cough, expectoration, chest tightness, shortness of breath, and hemoptysis. CT cavity lesions involving the lung, often occurs in the lung after the tip section, after the back section and basal segment, thick-walled cavity, may be accompanied by satellite lesions, endobronchial spread focal, pneumothorax, pleural effusion, etc. 1225 cases of group B patients haemoptysis of 59 patients, cavity in 3 patients, haemoptysis and/or cavity rate was lower than that in group A, the difference was statistically significant (P<0.05) . In group A, CT reexamination 6-24 months after anti-tuberculosis treatment showed that 52 cases (82.5%) had cavity reduction/healing, 8 cases (12.7%) had recurrence, and 3 cases (4.8%) had damaged lung (2 died) . Conclusion: Silicosis patients with hemoptysis and/or CT in cavity should be more vigilant about combined tuberculosis, anti-tuberculosis treatment and/or dynamic CT follow-up helps laboratory diagnosis negative patients.

[Diffuse interstitial lung disease of possible occupational origin treated at the Navarra Health Service. Navarra, Spain, 2017-2022]. / Enfermedad pulmonar intersticial difusa de posible origen laboral atendida en el Servicio Navarro de Salud. Navarra, España, 2017-2022.

INTRODUCTION: Diffuse interstitial lung disease (ILD) describes a broad group of pulmonary inflammatory and fibrosis disorders. Asbestosis and silicosis are the main causes linked to occupational exposure. The aim of this study was to estimate the proportion of cases with possible occupational origin and describe their exposure, clinical, and occupational status. METHOD: We conducted a retrospective longitudinal study of ILD cases between 2017 - 2022 at the University Hospital of Navarra was conducted. Information was supplemented with interviews of cases with possible occupational origin. The occupational proportion was calculated, labor and clinical characteristics analyzed, by statistical comparison of percentages and means. RESULTS: Out of 1067 ILD cases, 56 had a possible occupational origin 5,2% (95% CI 3,9-6,6%). 36 (64,3%) corresponded to asbestosis, 15 (26,8%) to silicosis, and 5 (8,9%) to unspecified pneumoconiosis. The most frequent activities in silicosis were "stone cutting-carving" and in asbestosis "manufacture of iron products". The average age of asbestosis cases was higher than that of silicosis cases (78,2 vs. 67,3 years), as well as their clinical manifestation. Five cases (8,9%) had been recognized as occupational diseases. CONCLUSIONS: The implementation of a computer tool in medical records has made it possible to estimate the magnitude and assess the evolution of occupational ILD treated in the Public Health Service. Economic activities reflect the economic risk structure of the region. However, there is a lack of recognition of these diseases as occupational illnesses and they represent a preventable burden of respiratory disease.

Introducción: La enfermedad pulmonar intersticial difusa (EPID) describe un amplio grupo de trastornos con inflamación y fibrosis pulmonar. La asbestosis y la silicosis son las principales causas por exposición laboral. El objetivo de este trabajo fue estimar la proporción de casos de posible origen laboral y describir la exposición, situación clínica y laboral.  Método: Estudio longitudinal retrospectivo de los casos de EPID, en el período 2017-2022 en el Hospital Universitario de Navarra. Se completó la información con entrevista a los casos de posible origen laboral.  Resultados: De un total de 1067 casos de EPID, 56 tuvieron un posible origen laboral, 5,2% (3,9-6,6 IC 95%) 36 (64,3%) correspondieron a asbestosis, 15 (26,8%) a silicosis y 5 (8,9%) a neumoconiosis no especificada. Las actividades más frecuentes en silicosis fueron "corte-tallado de piedra" y para asbestosis "fabricación productos hierro". La media de edad de los casos de asbestosis fue superior a los de silicosis (78,2 vs. 67,3 años), así como su afectación clínica. Cinco casos (8,9%) habían sido reconocidos como enfermedad profesional  Conclusiones: La implementación de una herramienta informática en historia clínica ha hecho posible estimar la magnitud y valorar la evolución de las EPID laborales atendidas en el servicio nacional de salud. Las actividades económicas reflejan la estructura económica de riesgo de la región. Sin embargo, existe una falta de su reconocimiento como enfermedad profesional y suponen una carga de enfermedad respiratoria evitable.

[Australia's engineered stone ban. A sound decision]. / La prohibición de los aglomerados de cuarzo en Australia, una decisión modélica.

Australia se convirtió en diciembre de 2023 en el primer país en prohibir el uso de los aglomerados de cuarzo. El consumo de estos materiales sintéticos, que contienen más del 80% de sílice cristalina y que desde los años 90 se han empleado para la fabricación de encimeras de cocina y baños, ha contribuido al resurgimiento en numerosos países de formas aceleradas de silicosis y a una notable incidencia de enfermedades sistémicas. El objeto de este trabajo es analizar los fundamentos que sustentan la decisión australiana. Dichos fundamentos están principalmente recogidos en el informe elaborado en 2023 por la agencia gubernamental Safe Work Australia (SWA), que recomendó la prohibición del producto. SWA llevó a cabo una consulta pública entre todos los actores sociales y científicos interesados en el problema. El informe de SWA señaló la ausencia de evidencia científica sobre un umbral de sílice toxicológicamente seguro cuestionando la estrategia de los fabricantes del material de presentar como productos seguros a los aglomerados con menos del 40% de contenido de sílice. La recomendación de SWA tomó en consideración la evaluación del nivel de cumplimiento de las estrictas medidas de prevención implementadas entre 2019 y 2023, constatando que el incumplimiento siguió siendo generalizado en el sector. Además se realizó un análisis coste-beneficio para valorar el número de casos de silicosis que sería necesario evitar para "compensar" los costes económicos asociados a cada opción de prohibición. Para ello empleó el Valor Estadístico de la Vida (VEV) actualizado en 2023 en Australia y estimó en 4,9 millones de dólares australianos cada vida salvada y silicosis evitada. En nuestra opinión, la prohibición australiana es modélica por la forma en que se ha gestado la decisión, por su sólida fundamentación científica y socio-laboral, y por la aplicación del principio de precaución.

FOXF1 reverses lung fibroblasts transdifferentiation via inhibiting TGF-ß/SMAD2/3 pathway in silica-induced pulmonary fibrosis.

Silicosis is one of the most common and severe types of pneumoconiosis and is characterized by lung dysfunction, persistent lung inflammation, pulmonary nodule formation, and irreversible pulmonary fibrosis. The transdifferentiation of fibroblasts into myofibroblasts is one of the main reasons for the exacerbation of silicosis. However, the underlying mechanism of transcription factors regulating silicosis fibrosis has not been clarified. The aim of this study was to investigate the potential mechanism of transcription factor FOXF1 in fibroblast transdifferentiation in silica-induced pulmonary fibrosis. Therefore, a silicosis mouse model was established, and we found that FOXF1 expression level was significantly down-regulated in the silicosis group, and after overexpression of FOXF1 by adeno-associated virus (AAV), FOXF1 expression level was up-regulated, and silicosis fibrosis was alleviated. In order to further explore the specific regulatory mechanism of FOXF1 in silicosis, we established a fibroblasts transdifferentiation model induced by TGF-ß in vitro. In the model, the expression levels of SMAD2/3 and P-SMAD2/3 were up-regulated, but the expression levels of SMAD2/3 and P-SMAD2/3 were down-regulated, inhibiting transdifferentiation and accumulation of extracellular matrix after the overexpressed FOXF1 plasmid was constructed. However, after silencing FOXF1, the expression levels of SMAD2/3 and P-SMAD2/3 were further up-regulated, aggravating transdifferentiation and accumulation of extracellular matrix. These results indicate that the activation of FOXF1 in fibroblasts can slow down the progression of silicosis fibrosis by inhibiting TGF-ß/SMAD2/3 classical pathway, which provides a new idea for further exploration of silicosis treatment.

Enfermedad pulmonar intersticial difusa de posible origen laboral atendida en el Servicio Navarro de Salud. Navarra, España, 2017-2022 / Diffuse interstitial lung disease of possible occupational origin treated at the Navarra Health Service. Navarra, Spain, 2017-2022

Introducción: La enfermedad pulmonar intersticial difusa (EPID) describe un amplio grupo de trastornos con inflamación y fibrosis pulmonar. La asbestosis y la silicosis son las princi-pales causas por exposición laboral. El objetivo de este trabajo fue estimar la proporción de casos de posible origen laboral y describir la exposición, situación clínica y laboral. Método: Estudio longitudinal retrospectivo de los casos de EPID, en el período 2017-2022 en el Hospital Universitario de Navarra. Se completó la información con entrevista a los casos de posible origen laboral. Se calculó la proporción de casos de origen laboral y se analizaron las características laborales y clínicas, con comparación estadística de porcen-tajes y medias. Resultados: De un total de 1067 casos de EPID, 56 tuvieron un posible origen laboral, 5,2% (3,9-6,6 IC 95%) 36 (64,3%) correspondieron a asbestosis, 15 (26,8%) a silicosis y 5 (8,9%) a neumoconiosis no especificada. Las actividades más frecuentes en silicosis fueron “cor-te-tallado de piedra” y para asbestosis ”fabricación productos hierro”. La media de edad de los casos de asbestosis fue superior a los de silicosis (78,2 vs. 67,3 años), así como su afec-tación clínica. Cinco casos (8,9%) habían sido reconocidos como enfermedad profesional Conclusiones: La implementación de una herramienta informática en historia clínica ha he-cho posible estimar la magnitud y valorar la evolución de las EPID laborales atendidas en el servicio nacional de salud. Las actividades económicas reflejan la estructura económica de riesgo de la región. Sin embargo, existe una falta de su reconocimiento como enfermedad profesional y suponen una carga de enfermedad respiratoria evitable.(AU)

Introduction: Diffuse interstitial lung disease (ILD) describes a broad group of pulmonary inflammatory and fibrosis disorders. Asbestosis and silicosis are the main causes linked to occupational exposure. The aim of this study was to estimate the proportion of cases with possible occupational origin and describe their exposure, clinical, and occupational status.Method: We conducted a retrospective longitudinal study of ILD cases between 2017 - 2022 at the University Hospital of Navarra was conducted. Information was supplemented with interviews of cases with possible occupational origin. The occupational proportion was cal-culated, labor and clinical characteristics analyzed, by statistical comparison of percenta-ges and means.Results: Out of 1067 ILD cases, 56 had a possible occupational origin 5,2% (95% CI 3,9-6,6%). 36 (64,3%) corresponded to asbestosis, 15 (26,8%) to silicosis, and 5 (8,9%) to unspe-cified pneumoconiosis. The most frequent activities in silicosis were "stone cutting-carving" and in asbestosis "manufacture of iron products". The average age of asbestosis cases was higher than that of silicosis cases (78,2 vs. 67,3 years), as well as their clinical manifesta-tion. Five cases (8,9%) had been recognized as occupational diseases.Conclusions: The implementation of a computer tool in medical records has made it pos-sible to estimate the magnitude and assess the evolution of occupational ILD treated in the Public Health Service. Economic activities reflect the economic risk structure of the region. However, there is a lack of recognition of these diseases as occupational illnesses and they represent a preventable burden of respiratory diseas:(AU)

Paeoniflorin mitigates MMP-12 inflammation in silicosis via Yang-Yin-Qing-Fei Decoction in murine models.

BACKGROUND: Silicosis presents a significant clinical challenges and economic burdens, with Traditional Chinese Medicine (TCM) emerging as a potential therapeutic avenue. However, the precise effects and mechanisms of TCM in treating silicosis remain uncertain and subject to debate. OBJECTIVE: The study aims to elucidate the therapeutic role and mechanisms of the Yang-Yin-Qing-Fei Decoction (YYQFD) and its key component, paeoniflorin, in silicosis using a murine model. METHODS: Silicotic mice were treated with YYQFD, pirfenidone (PFD), or paeoniflorin. RAW264.7 cells and mouse lung fibroblasts (MLF) were stimulated with silica, matrix metalloproteinase-12 (MMP-12), or TGF-ß1, followed by treatment with paeoniflorin, PFD, or relevant inhibitors. YYQFD constituents were characterized using High-Performance Liquid Chromatography (HPLC). Lung fibrosis severity was assessed via histopathological examination, micro-CT imaging, lung functions, and Western blot analysis. Transcriptome sequencing and bioinformatics analysis were employed to delineate the gene expression profile and target genes modulated by YYQFD in silicosis. RESULTS: Treatment with YYQFD ameliorated silica-induced lung fibrosis. Transcriptome sequencing identified MMP-12 as a potential common target of YYQFD and PFD. Additionally, a potential pro-inflammatory role of MMP-12, regulated by silica-induced TLR4 signaling pathways, was revealed. Paeoniflorin, one of the most distinctive compounds in YYQFD, attenuated silica-induced MMP-12 increase and its derived inflammatory factors in macrophages through a direct binding effect. Notably, paeoniflorin treatment exerted anti-fibrotic effects by inhibiting MMP-12-derived inflammatory factors and TGF-ß1-induced myofibroblast differentiation in silica-exposed mice. CONCLUSIONS: This study underscores paeoniflorin as one of the most principal bioactive compounds in YYQFD, highlighting its capacity to attenuate lung inflammation driven by macrophage-derived MMP-12 and reduce lung fibrosis both in vivo and in vitro.

Daphnetin alleviates silica-induced pulmonary inflammation and fibrosis by regulating the PI3K/AKT1 signaling pathway in mice.

Silicosis is a hazardous occupational disease caused by inhalation of silica, characterized by persistent lung inflammation that leads to fibrosis and subsequent lung dysfunction. Moreover, the complex pathophysiology of silicosis, the challenges associated with early detection, and the unfavorable prognosis contribute to the limited availability of treatment options. Daphnetin (DAP), a natural lactone, has demonstrated various pharmacological properties, including anti-inflammatory, anti-fibrotic, and pulmonary protective effects. However, the effects of DAP on silicosis and its molecular mechanisms remain uncover. This study aimed to evaluate the therapeutic effects of DAP against pulmonary inflammation and fibrosis using a silica-induced silicosis mouse model, and investigate the potential mechanisms and targets through network pharmacology, proteomics, molecular docking, and cellular thermal shift assay (CETSA). Here, we found that DAP significantly alleviated silica-induced lung injury in mice with silicosis. The results of H&E staining, Masson staining, and Sirius red staining indicated that DAP effectively reduced the inflammatory response and collagen deposition over a 28-day period following lung exposure to silica. Furthermore, DAP reduced the number of TUNEL-positive cells, increased the expression levels of Bcl-2, and decreased the expression of Bax and cleaved caspase-3 in the mice with silicosis. More importantly, DAP suppressed the expression levels of NLRP3 signaling pathway-related proteins, including NLRP3, ASC, and cleaved caspase-1, thereby inhibiting silica-induced lung inflammation. Further studies demonstrated that DAP possesses the ability to inhibit the epithelial mesenchymal transition (EMT) induced by silica through the inhibition of the TGF-ß1/Smad2/3 signaling pathway. The experimental results of proteomic analysis found that the PI3K/AKT1 signaling pathway was the key targets of DAP to alleviate lung injury induced by silica. DAP significantly inhibited the activation of the PI3K/AKT1 signaling pathway induced by silica in lung tissues. The conclusion was also verified by the results of molecular and CETSA. To further verify this conclusion, the activity of PI3K/AKT1 signaling pathway was inhibited in A549 cells using LY294002. When the A549 cells were pretreated with LY294002, the protective effect of DAP on silica-induced injury was lost. In conclusion, the results of this study suggest that DAP alleviates pulmonary inflammation and fibrosis induced by silica by modulating the PI3K/AKT1 signaling pathway, and holds promise as a potentially effective treatment for silicosis.

[Research progress of macrophage polarization in silicosis fibrosis].

Silicosis is a common occupational disease, and its main characteristic pathological features are the formation of silicon nodules and diffuse pulmonary fibrosis. In the process of silicosis fibrosis, macrophages can be polarized into M1 macrophages and M2 macrophages. M1 macrophages play a pro-inflammatory role in the early stage of silicosis and release a variety of inflammatory factors, which is the core of inflammatory response. M2 macrophages promote inflammation resolution and tissue repair in silicosis fibrosis stage by secreting anti-inflammatory cytokines and pro-fibrotic mediators. M1/M2 polarization balance plays an important role in the occurrence and development of silicosis, and the regulation of macrophage polarization direction may play a positive role in the prevention and treatment of silicosis fibrosis. In this review, the role of macrophage polarization in silicosis fibrosis, the related signaling pathways regulating macrophage polarization in silicosis fibrosis, and the potential therapeutic targets based on macrophage polarization in silicosis fibrosis are reviewed, with a view to further strengthening the understanding of the mechanism of macrophage polarization in the pathogenesis and treatment of silicosis fibrosis.

[5 cases of silicosis complicated with connective tissue diseases].

Long-term inhalation of silica dust can cause silicosis, but also may induce autoimmune diseases, such as systemic sclerosis, rheumatoid arthritis, systemic lupus erythematosus, Sjogren's syndrome, anti-histidyl tRNA synthetase antibody (JO-1 antibody) syndrome. These two diseases can be isolated or combined. In this paper, the clinical characteristics of 5 cases of silicosis complicated with connective tissue diseases were analyzed and summarized to strengthen the clinical understanding of silicosis complicated with connective tissue diseases, so as to reduce its misdiagnosis and missed diagnosis, and provide reference for clinicians in diagnosis and treatment.

[A case of silicosis complicated with non-tuberculous mycobacterium pulmonary disease].

Non-tuberculosis mycobacterium (NTM) refers to a general term for a large group of mycobacteria, excluding the mycobacterium tuberculosis and mycobacterium leprae, which is an opportunistic pathogen. NTM pulmonary disease and pulmonary tuberculosis have very similar clinical and imaging manifestations. Ordinary sputum tests can not distinguish between mycobacterium tuberculosis and NTM accurately, and it needs to be differentiated through detection methods such as mycobacterium culture medium, high-performance liquid chromatography, and molecular biology. During the diagnosis of occupational pneumoconiosis, a sandblasting and polishing worker's lung CT showed dynamic changes in infiltrating shadows and cavities in the right lung. A sputum drug sensitivity test showed NTM infection, but the patient refused treatment. After 20 months, the CT examination of the lung showed further enlargement of infiltrating shadows and cavities, and NTM bacterial identification showed intracellular mycobacterial infection. Amikacin, moxifloxacin, azithromycin, and ethambutol combined antibacterial treatment were given. Currently, the patient is still under treatment.