Inhibition of the ITGB1 gene attenuates crystalline silica-induced pulmonary fibrosis via epithelial-mesenchymal transformation

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.

Intervention effect of miR-204-3P on silica dust-induced silicosis fibrosis in rats / 环境与职业医学

Background Long-term exposure to free silica particles will lead to fibrosis of lung tissue, and abnormal expression of microRNA (miRNA) may affect the occurrence and process of fibrosis. Objective To observed possible intervention effect of miR-204-3p overexpression adenovirus on silicosis fibrosis induced by silica dust using a silicosis rat model via non-exposed intratracheal instillation. Methods Forty SD rats were randomly divided into four groups: control group, silicosis model group, miRNA-NC group, and miR-204-3p intervention group. Under ether anesthesia, rats in the silicosis model group, miRNA-NC group, and miR-204-3p intervention group were injected with 1 mL (50 mg·mL−1) of free silica dust suspension into the trachea, while the control group was injected with the same volume of normal saline. After 30 d of dust exposure, the miR-204-3p intervention group was injected with rno-mir-204 adenovirus vector to overexpress miR-204-3p, and the miRNA-NC group was given empty virus vector. After 30 d of normal feeding, the animals were sacrificed by chloral hydrate anesthesia, and the lung tissue was taken for subsequent experiments. The relative expression level of miR-204-3p in lung tissue of rats in each group was detected by real-time fluorescence quantitative PCR (RT-qPCR). HE staining, Masson staining, and Sirius red staining were used for pathological observation. Immunohistochemistry was used to detect the expression of Fibronectin and Collagen I in lung tissue of rats in each group. RT-qPCR was used to detect the relative gene expression levels of fibrosis markers Fibronectin, Vimentin, Collagen I, and Collagen III in lung tissue of rats in each group. Western blot was used to detect the protein expression levels of fibrosis markers Fibronectin, Vimentin, Collagen I, and Collagen III in lung tissue of rats in each group. Results The anatomical features of lung tissue in the control group were pink lung tissue with soft texture and smooth surface, while those in the silicosis model were grayish white tissue with hard texture and scars and grayish white silicon nodules on the surface. Compared with the silicosis model group, the color of lung tissue in the miR-204-3p intervention group became ruddy, the surface was smooth, and the texture became soft. The staining results showed that the alveolar wall of the control group was thin, there were a small number of capillaries in the alveoli, and the alveolar structure was clear and complete. In the silicosis model group, the alveolar wall became thicker, the pulmonary septum was partially broken, the alveolar structure was defective, and a large amount of collagen fibers were deposited. The alveolar structure of the miR-204-3p intervention group was relatively clear and there was a small amount of collagen fiber deposition. RT-qPCR results showed that compared with the control group, the relative expression levels of miR-204-3p in lung tissue of the silicosis model group and the miRNA-NC group were decreased (P<0.05), and the relative expression level of miR-204-3p in lung tissue of the miR-204-3p intervention group was increased (P＜0.05). The results of immunohistochemistry showed that compared with the control group, the expression levels of Fibronectin and Collagen I in lung tissue of the silicosis model group were increased (P＜0.05). Compared with the silicosis model group, the relative expression levels of Fibronectin and Collagen I in lung tissue of the rats in the miR-204-3p intervention group were significantly decreased (P<0.05). The results of RT-qPCR and Western blot showed that compared with the control group, the relative protein and gene expression levels of fibrosis factors Fibronectin, Vimentin, Collagen I, and Collagen III in lung tissue of the silicosis model group increased (P＜0.05). Compared with the silicosis model group, the relative gene and protein expression levels of fibrosis factors Fibronectin, Vimentin, Collagen I, and Collagen III in lung tissue of rats in the miR-204-3p intervention group were decreased (P＜0.05). Conclusion Silica dust can cause lung fibrosis in rats, and overexpression of miR-204-3P in vivo can reduce silicosis fibrosis in rats caused by silica dust.

Effects of different concentrations of brusatol on silicosis fibrosis in mice / 环境与职业医学

Background Silicosis is a diffuse fibrosis of the lungs caused by long-term inhalation of free silicon dioxide (SiO2). It has a complex pathogenesis and lacks effective treatment. Brusatol (Bru) has a variety of biological activities, and its role in silicosis fibrosis is unclear yet. Objective To investigate the effects of different concentrations of Bru on SiO2-induced silicosis fibrosis in mice. Methods Thirty male C57BL/6J mice were randomly divided into five groups: a control group, a silica group, and three Bru intervention groups with low, medium, and high doses (1, 2, and 4 mg·kg−1), with 6 mice in each group. Except the control group, the remaining groups were established as SiO2-induced silicosis mouse models by using a single tracheal infusion of 50 μL 60 mg·mL−1 SiO2 suspension. The control group was dosed with equal amount of saline. The Bru intervention groups were injected intraperitoneally with Bru for 5 consecutive days and then injected every other day. After 28 d of exposure, the mice were executed and lung tissues were collected. The lung coefficient of the mice was measured, and the pathological changes of the lung tissues were observed after hematoxylin-eosin (HE) and Masson staining. The levels of apoptotic protein Cleaved-caspase 3, fibrosis-related protein α-smooth muscle actin (α-SMA), type I collagen (Col-I), autophagy-associated protein Beclin1, microtubule-associated protein 1 light chain 3 (LC3), Sequestosome 1 (p62/SQSTM1), Kelch like ECH-associated protein-1 (Keap1), and nuclear factor erythroid 2 related factor 2 (Nrf2) were detected by Western blot. The mRNA levels of Caspase 3, α-SMA, and Col-I were measured by realtime fluorescence-based quantitative PCR. Results Compared with the control group, the lung coefficient of mice in the silica group was significantly increased (P < 0.01); the lung tissues of the silicosis mice showed damaged alveolar walls, along with infiltration of inflammatory cells, fibrous nodules, and collagen deposition; furthermore, the protein and mRNA levels of Cleaved-caspase 3, α-SMA, and Col-I were significantly increased (P < 0.01); the expression levels of Beclin1, LC3-II/I, p62, and Nrf2 were increased, while that of Keap1 was decreased (P < 0.05). The interventions with low and medium doses of Bru reduced lung coefficient (P < 0.05) and protected against pathological damage and collagen deposition in the lung tissues of the silicosis mice; the protein and mRNA expression levels of Cleaved-caspase 3, α-SMA, and Col-I were significantly decreased in the low and medium dose groups (P < 0.05, P < 0.01), the expression levels of Beclin1, LC3-II/I, p62, and Nrf2 were also decreased (P < 0.05, P < 0.01), and the expression level of Keap1 was increased in the medium dose group (P < 0.05). However, compared with the silica group, the differences in lung coefficient, pathological damage, and protein and mRNA expression levels of Cleaved-caspase 3, α-SMA, and Col-I in the Bru high dose group were not statistically significant (P > 0.05). In addition, the high dose of Bru decreased Beclin1, LC3-II/I, and Nrf2 expression levels (P < 0.01), did not change p62 protein expression level (P > 0.05), while increased Keap1 protein level (P < 0.01). Conclusion Low and medium doses of Bru might regulate autophagy through the Keap1-Nrf2 pathway, ameliorate autophagic degradation impairment, reduce pulmonary coefficient, attenuate apoptosis, and delay the progression of fibrosis in SiO2-induced silicosis mice.

Relationship between plasma SP-A expression level and disease stage in silicosis patients / 上海预防医学

ObjectiveTo investigate the relationship between plasma surfactant protein⁃A （SP⁃A） expression level and silicosis progression， and to provide early evidence for exploring whether SP⁃A can be used as a biomarker for clinical monitoring of silicosis disease progression. MethodsWe recruited 187 silicosis patients in Guangdong Province hospital for occupational disease prevention and treatment between November， 2019 and November，2020. Their peripheral venous blood samples were collected for the plasma isolation. The level of pulmonary SP⁃A was detected by enzyme-linked immunosorbent assay. ResultsThere was a statistically significant difference in the level of SP⁃A among the silicosis groups （P<0.05）， and the plasma SP-A level of the silicosis patients in stage Ⅲ was higher than that in stage Ⅰ and stage Ⅱ （P<0.05）. Smoking had effect on plasma SP⁃A levels， Age， working years and drinking had no effect on plasma SP⁃A levels. ConclusionThe expression level of SP⁃A in the plasma of silicosis patients is increased， which has a certain correlation with the disease stage， and plays a certain early warning role in the occurrence and development of silicosis， and may be a potential biomarker for the diagnosis and prognosis of silicosis.

Oxamate alleviates silicotic fibrosis in mice by inhibiting senescence of alveolar type II epithelial cells / 环境与职业医学

Background The senescence of alveolar type II epithelial cells is an important driving factor for the progression of silicotic fibrosis, and the regulatory effects of oxamate on the senescence of alveolar type II epithelial cells is still unclear. Objective To explore whether lactate dehydrogenase inhibitor oxamate can alleviate silicotic fibrosis in mice by inhibiting senescence of alveolar type II epithelial cellsMethods This study was divided into two parts: in vivo experiments and in vitro experiments. In the first part, forty SPF C57BL/6J male mice were randomly divided into four groups with 10 in each group: control group, silicosis model group, low-dose oxamate treatment group, and high-dose oxamate treatment group. The silicotic mouse model was established by intratracheal instillation of 50 μL SiO2 suspension (100 mg·mL−1). The treatment models were prepared by intraperitoneal injection of 100 μL oxamate (225 mmol·L−1 and 1125 mmol·L−1). In the second part, induction of MLE-12 mouse alveolar type II epithelial cells was conducted with SiO2. The in vitro experimental groups were ① SiO2 induction groups: control group, 50 μg·mL−1 SiO2 group, 100 μg·mL−1 SiO2 group, and 200 μg·mL−1 SiO2 group, and ② oxamate treatment groups: control group, SiO2 group (100 μg·mL−1), low-dose oxamate (25 mmol·L−1) treatment group, and high-dose oxamate (50 mmol·L−1) treatment group. Pathological morphology of lung tissues was evaluated after hematoxylin-eosin (HE) staining; deposition of collagen in lung tissues was evaluated after sirius red staining; positive co-expression of prosurfactant protein C (Pro-SPC) and β-galactosidase was detected by immunofluorescence staining; positive expression of β-galactosidase in MLE-12 cells was detected by immunofluorescence staining. The protein expression levels of collagen type I (CoL I), fibronectin1 (FN1), hexokinase 2 (HK2), pyruvate kinase isozyme type M2 (PKM2), lactate dehydrogenase A (LDHA), p-ataxia telangiectasia and Rad3-related kinase (ATR), and cyclin-dependent kinase inhibitors p21, and p16 were detected by Western blotting. Results Compared with the control group, the protein expression levels of HK2, PKM2, LDHA, p-ATR, p21, and p16 were significantly upregulated in the silicosis model group and the SiO2-induced MLE-12 cells (P＜0.05). The in vivo studies showed that, compared with the control group, the silicon nodule area, the collagen deposition area, the proportion of β-galactosidase positive cells, and the protein expression levels of CoL I, FN1, LDHA, p-ATR, p21, and p16 were significantly upregulated in the silicosis model group (P＜0.05). Compared with the silicosis model group, the oxamate treatment groups showed significant downregulation of the silicon nodule area, the collagen deposition area, the proportion of β-galactosidase positive cells, and the the CoL I, FN1, LDHA, p-ATR, p21, and p16 protein expression levels, and the high-dose oxamate treatment group showed a higher efficacy on these indicators than the low-dose oxamate treatment group (P＜0.05). The in vitro studies showed that, compared with the control group, the proportion of β-galactosidase positive cells and the protein expression levels of p-ATR, p21, and p16 were significantly upregulated in the SiO2-induced group (P＜0.05). Compared with the SiO2 group, the proportion of β-galactosidase positive cells and the LDHA, p-ATR, p21 and p16 protein expression levels were significantly downregulated in the oxamate treatment groups, and the high-dose oxamate treatment group showed a higher efficacy on these indicators than the low-dose oxamate treatment group (P＜0.05). Conclusion Lactate dehydrogenase inhibitor oxamate can alleviate silicotic fibrosis in mice by inhibiting the senescence of alveolar type II epithelial cells.

Characterization and correlation analysis of lung flora in rats with silica-induced acute lung injury / 中国病理生理杂志

AIM:To elucidate the possible biological mechanism of silica-induced acute lung injury in rats.METHODS:Sixteen Male Sprague-Dawley rats were divided into control and acute silicosis model groups,and instilled intratracheally with 1 mL of normal saline and 50 g/L silica suspension,respectively.After 7 d,the rats were sacrificed for collection of lung tissue and serum.The serum levels of interleukin-1β(IL-1β),IL-18 and tumor necrosis factor-α(TNF-α)were measured by using ELISA.The protein expression levels of nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)and gasdermin D(GSDMD)were measured by immunohistochemistry.Bacterial DNA was ex-tracted from the lung tissue for 16S ribosomal RNA gene sequencing to characterize changes in the composition of lung flo-ra.The differences in the structure of bacterial flora between control and model groups were analyzed by bioinformatic analy-ses.RESULTS:Immunohistochemical analysis showed that the protein expression levels of NLRP3 and GSDMD were higher in the lungs of the rats in model group.In addition,serum cytokine profiling showed that IL-1β,IL-18 and TNF-α levels were significantly higher in model group.The most abundant bacterial genera in the lung flora of the rats in model group were Bifidobacterium,Clostridium sensu stricto 1,and Parasutterella.The NLRP3 and GSDMD levels in the lung tissue and IL-1β and TNF-α levels in serum were positively correlated with the abundance of Parasutterella.CONCLU-SION:The alterations in lung flora structure and increased inflammation levels may be the actual biological mechanisms underlying silica-induced acute lung injury.The modulation of lung flora may provide a basis for the prevention and treat-ment of silica-induced acute lung injury.

Network pharmacology reveals the effect and mechanism of Ganoderma leucocontextum ethanol extract on improving inflammatory response in silicosis lungs / 中国职业医学

ObjectiveTo explore the effect of Ganoderma leucocontextum ethanol extract (GLE) on silicosis and its potential molecular mechanism using network pharmacology, molecular docking technology and animal experiments. Methods i) The components of GLE were analyzed using ultra-performance liquid chromatography-Q Exactive-mass spectrometry (UPLC-QE-MS) method. The active components, potential molecular pathways and targets of GLE in the intervention of inflammation process of silicosis was explored using network pharmacology and molecular docking technology. ii) Specific pathogen free male C57BL6/J mice were divided into four groups with 10 mice in each group. The mice in the silicosis model group and GLE intervention group were given a dose of 80 μL silica suspension with a mass concentration of 50 g/L once by non-exposed tracheal instillation, and the mice in the blank control group and GLE control group were given an equal volume of sterile 0.9% sodium chloride solution. From the second day after modeling, GLE control group and GLE intervention group were given GLE at a dose of 200 mg/(kg•d) by gavage, while blank control group and silicosis model group were given the same volume of 0.9% sodium chloride solution by gavage, once per day for 35 days. After that, the histopathological changes of lung tissues of mice were observed, the lung mass coefficient, inflammation score and the ratio of collagen deposition area were calculated, and the levels of tumor necrosis factor (TNF) -α, interleukin (IL) -1β and IL-6 in the lung tissues of mice were detected by enzyme-linked immunosorbent assay. Results i) A total of 76 active components of GLE were detected by UPLC-QE-MS. Among them, 36 ingredients met the screening criteria of the five principles of drug-like components. A total of 67 potential targets of the 36 GLE active ingredients to improve the inflammatory response of silicosis were screened based on the network pharmacology theory. The result of Kyoto Encyclopedia of Genes and Genomes enrichment analysis and Gene Ontology functional analysis showed that IL signaling and cytokine signaling of immune cells played a key role in the process of anti-silicosis of GLE. The results of molecular docking showed that the top 10 targets based on the 67 intersection targets were TNF, IL6, B-cell lymphoma 2, cellular tumor antigen p53, Caspase-3 subunit p12, JUN, epidermal growth factor receptor, IL1B, 67 kDa matrix metalloproteinase-9 and prostaglandin G/H synthase 2. The result of protein-protein interaction analysis showed that glycyrrhetinic acid had the strongest affinity with the key targets TNF-α, IL-1β and IL-6, followed by ganoderma acid DM, alismatol C, ganoderma acid β and red sapogenin. ii) The results of histopathological examination showed that the inflammatory response and collagen deposition were alleviated in the lungs of mice with silicosis. The lung mass coefficient, inflammation score, ratio of collagen deposition area and IL-6 expression in lung were lower in mice of the GLE intervention group (all P<0.05), compared with the silicosis model group. However, there was no significant difference in the levels of TNF-α and IL-1β in lung tissues between the two groups (all P>0.05). Conclusion GLE may reduce silica-induced lung inflammation and fibrosis by inhibiting the IL-6 level in lung tissues of mice. Its mechanism is associated with the synergistic action of multi-components, multi-targets and multi-pathways.

Un caso poco frecuente: síndrome de Erasmus y tuberculosis / A rare case: Erasmus syndrome and tuberculosis

Resumen Presentamos el caso de un hombre de 35 años, are nador durante ocho años, con diagnóstico reciente de tuberculosis pulmonar y esclerosis sistémica, que ingre só por cuadro de disnea y mal estado general. Se realizó radiografía de tórax donde se evidenció neumotórax grado I, en la tomografía de tórax, también presentó masas hiperdensas confluyentes, asociadas a un patrón de neumonía intersticial no especifica (NSIP), hallazgos compatibles con silicosis pulmonar complicada. Debi do al avanzado estadio clínico, no pudieron realizarse estudios diagnósticos invasivos ni estudios de función pulmonar. Como tratamiento inicial se colocó un tubo de avenamiento pleural, se realizó tratamiento antifímico y se indicó oxigenoterapia crónica domiciliaria. Se remitió al paciente a consultorios de enfermedades intersticia les y reumatología para un manejo multidisciplinario, aunque el cuadro infeccioso contraindicó la posibilidad de un tratamiento inmunosupresor. Finalmente, el pa ciente falleció bajo cuidados paliativos. La inhalación de sílice es la causa de la silicosis, pero también está implicada en el desarrollo de la esclerosis sistémica (síndrome de Erasmus) y aunque comparten un factor de riesgo común, es raro encontrar ambas enfermedades coexistiendo. Presentamos el caso de un paciente joven donde ambas condiciones se presentaron de manera agresiva, con el objetivo de remarcar la importancia de la búsqueda activa de las enfermedades por exposición y sus condiciones asociadas.

Abstract We present the case of a 35-year-old male patient, sandblaster for eight years, recently diagnosed with pulmonary tuberculosis and systemic sclerosis, who was admitted with dyspnea and poor general condition. Chest X-ray showed a grade I pneumothorax, and on the chest tomography he presented confluent hyperdense masses associated with a pattern of non- specific in terstitial pneumonia (NSIP), findings compatible with complicated silicosis. Due to the advanced clinical stage, neither invasive diagnostic test nor pulmonary func tion test could be performed. Initial treatment included placement of a pleural drainage tube, antituberculosis treatment and chronic home oxygen. The patient was referred to the interstitial disease and rheumatology de partments for multidisciplinary management, although the infectious condition contraindicated the possibility of immunosuppressive treatment. The patient eventu ally died under palliative care. Silica inhalation is the cause of silicosis, but it is also implicated in the devel opment of systemic sclerosis (Erasmus syndrome) and although they share a common risk factor, it is rare to find both diseases coexisting. We present the case of a young patient in whom both diseases presented aggres sively, with the aim of highlighting the importance of actively searching for expositional diseases and associ ated conditions.

Metabolomics insights into the mechanism by which Jinshui Chenfei formula ameliorates silica-induced fibrosis in rats / 中国中西医结合急救杂志

Objective To exploring the mechanism of Jinshui Chenfei formula(JCF)in ameliorating silica(SiO2)-induced silicosis fibrosis based on endogenous metabolite changes.Methods A total of 32 SPF male Sprague-Dawley(SD)rats were divided into normal control group,model group,JCF group(9.72 g·kg-1·d-1),and Tetrandrine group(27 mg·kg-1·d-1)according to random number table method.The experimental silicosis model was established by intratracheal injection with SiO2 suspension(250 mg/kg)on day 1.From week 5-8,silicosis rats were treated with tetrandrine or JCF.On the end of week 8,the changes of pulmonary function index,including forced vital capacity(FVC),tidal volume(TV)and lung dynamic compliance(Cydn)were detected.The pathological changes of lung tissue were analyzed by hematoxyline-osin(HE)staining and Masson staining,the severity of focal alveolitis and fibrosis was also evaluated using the Szapiel scale and the Ashcroft scale,the positive staining of collagen Ⅰ(COL Ⅰ)and COL Ⅲ was detected using immunohistochemistry;the protein expression of transforming growth factor-β1(TGF-β1),fibronectin(FN),andα-smooth muscle actin(α-SMA)were measured by Western blotting.The rat serum samples were further screened for differential metabolites using ultra performance liquid chromatographytandem quadrupole time of flight mass spectrometr(UPLC-Q-TOF-MS)and pathway analysis was performed based on MetaboAnalyst 5.0.Results Compared with those in the normal control group,pathological changes such as alveolar structure destruction,the fibrous nodules encapsulated SiO2 particles were increased in lung tissues of rats in model group,alveolitis score and pulmonary fibrosis score were significantly higher(alveolitis score:2.62±0.27 vs.0.20±0.15,pulmonary fibrosis score:5.42±0.66 vs.0.50±0.84,both P<0.01);pulmonary function index including Cydn,FVC,and TV were significantly decreased[Cdyn(mL/cmH2O):0.26±0.03 vs.0.33±0.03,FVC(mL):8.09±0.47 vs.10.99±0.38,TV(mL):1.95±0.19 vs.2.53±0.26,all P<0.01];positive staining of COL Ⅰ,COL Ⅲ and ɑ-SMA,FN,TGF-β1 proteins expression showed higher in lung tissues[positive staining of COL Ⅰ(A value):13.47±1.76 vs.5.77±0.45;positive staining of COL Ⅲ(A value):10.39±0.47 vs.6.19±0.77,FN protein expression(FN/GAPDH):0.33±0.02 vs.0.21±0.07,α-SMA protein expression(α-SMA/GAPDH):1.78±0.16 vs.1.11±0.24,TGF-β1 protein expression(TGF-β1/GAPDH):0.52±0.10 vs.0.11±0.46,all P<0.01].Compared with the model group,the pathological changes of lung tissues were almost restored,alveolitis score and lung fibrosis score were significantly reduced in JCF and Tetrandrine groups(alveolitis score:1.10±0.15,1.33±0.31 vs.2.62±0.27,pulmonary fibrosis score:3.50±0.45,4.33±0.98 vs.5.42±0.66,all P<0.01);the pulmonary function index Cydn,FVC and TV were significantly increased[Cdyn(mL/cmH2O):0.32±0.05,0.31±0.04 vs.0.26±0.03,FVC(mL):9.41±0.85,8.70±0.92 vs.8.09±0.47,TV(mL):2.70±0.19,2.27±0.15 vs.1.95±0.19,all P<0.05];positive staining of COL Ⅰ,COL Ⅲ,and protein expression of FN,ɑ-SMA,and TGF-β1 in lung tissues was significantly decreased[COL Ⅰ(A value):7.09±0.67,8.13±0.64 vs.13.47±1.76,COL Ⅲ(A value):8.19±0.66,8.52±0.22 vs.10.39±0.47,FN protein expression(FN/GAPDH):0.19±0.06,0.24±0.03 vs.0.33±0.02,α-SMA protein expression(α-SMA/GAPDH):0.89±0.41,0.88±0.08 vs.1.78±0.16,TGF-β1 protein expression(TGF-β1/GAPDH):0.04±0.03,0.06±0.01 vs.0.52±0.10,all P<0.05].Metabolomics analysis showed that a total of 10 major differential metabolites were identified between normal control group,model group and JCF group,including arachidonic acid,palmitic acid,indole-3-acetic acid,propionylcarnitine,(S)-4-hydroxymandelonitrile,nalidixic acid,benzocaine,gramine,4-ethylphenol,N-benzylfor mamide.The differential metabolites in silicosis rats reversed by JCF treatment were mainly enriched,including unsaturated fatty acid biosynthesis,arachidonic acid metabolism,tryptophan metabolism,fatty acid elongation,fatty acid degradation and biosynthesis.Conclusion JCF could effectively improve the silicosis fibrosis,which is mainly related to biosynthesis of unsaturated fatty acids biosynthesis,arachidonic acid metabolism,tryptophan metabolism,fatty acid elongation,fatty acid degradation and biosynthesis.

Research progress on role of programmed cell death in silicosis and its possible mechanisms / 环境与职业医学

Silicosis is a common occupational disease caused by long-term inhalation of large amounts of free SiO2 dust and deposition in lung tissues, characterized by the formation of silicon nodules and diffuse fibrosis of lung tissues. Silicosis is one of the most common and serious occupational diseases in China, and its treatment imposes a huge economic burden on individuals and the country. The formation mechanism of silicosis is very complex, and no early screening indicators, effective drugs, and treatment methods are available yet. The current diagnosis of silicosis is based on occupational history and chest radiography findings, and it is irreversible once pulmonary fibrosis develops. Moreover, as silicosis is a continuously progressive disease, even if silicosis patients stop exposure to free SiO2 dust, their pulmonary fibrosis will continue to develop and deteriorate. Programmed cell death (autophagy, apoptosis, ferroptosis, etc.) is a key factor involved in the development of silicosis. This article summarized the important roles of programmed cell death, including autophagy, apoptosis, and ferroptosis, in silicotic fibrosis, and concluded that regulating different programmed cell death and related signaling pathways through effective means may delay the process of silicosis fibrosis, providing new ideas and clues for exploring potential mechanisms of silicosis formation and formulating prevention and treatment strategies.

The developments of silicosis drugs / 药学学报

Pneumoconiosis is the most common occupational disease in China, which severely endangers people's health. Depending on the inhaled air pollutants, pneumoconiosis is classified as anthracosis, silicosis, asbestosis, etc., among which silicosis is the most common and serious. Silicosis is a systemic, poor prognostic disease characterized by diffuse fibrosis of lung tissue, which is caused by long-term exposure to dust with high levels of free silicon dioxide (SiO2) in the occupational environment. Appropriate treatment in time is important for the disease. Unfortunately, no effective drugs have been approved to delay or even reverse pulmonary fibrosis caused by SiO2. This review briefly classifies potent therapeutic drugs and compounds in term of mechanisms, providing the probability for clinical treatment of silicosis.

Survival analysis on patients with occupational pneumoconiosis in Guangdong Province from 1980 to 2019 / 中国职业医学

Objective: To study the survival time and its risk factors of patients with occupational pneumoconiosis. Methods: A total of 11 011 newly diagnosed occupational pneumoconiosis patients in Guangdong Province from 1980 to 2019 were selected as study subjects. The life table method was used for survival analysis. The influencing factors of survival time of occupational pneumoconiosis patients were analyzed using the WilCoxon (Gehan) test and Cox proportional hazards regression model. Results: The median survival time of pneumoconiosis patients was 26.0 years. The median survival period of stage Ⅰpatients was 3.5 years longer than that of stage Ⅱ patients and 10.1 years longer than that of stage Ⅲ patients. The median survival time of patients with an initial diagnosis age under 40.0 years old was 34.8 years longer than that of patients with an initial diagnosis age over 60.0 years old. The median survival time of patients with dust exposure duration under 25.0 years old was 13.6 years longer than patients with dust exposure duration age over 45.0 years old. The results of the Cox proportional hazards regression model showed that the initial diagnosis stage, initial diagnosis age, dust exposure duration, and medical insurance were risk factors of the survival time of occupational pneumoconiosis patients (all P<0.01). The risk of reduced survival time for patients with stage Ⅱ and stage Ⅲ as the initial diagnosis stage was 1.15 and 2.04 times higher, respectively, compared with stage Ⅰ patients (both P<0.01). The risk of reduced survival time for patients without medical insurance was 60.22 times higher than those with medical insurance (P<0.01). Conclusion: The risk factors of the survival time of occupational pneumoconiosis patients in Guangdong Province are initial diagnosis stage, initial diagnosis age, the dust exposure age, and medical insurance. Earlier detection, earlier diagnosis, and improvement of medical insurance coverage for patients can effectively improve the survival time of occupational pneumoconiosis patients.

Analyzing the distribution characteristics of occupational pneumoconiosis in Sichuan Province, 2012-2021 / 中国职业医学

Objective: To analyze the distribution feature of occupational pneumoconiosis in Sichuan Province. Methods: The cases of newly diagnosed occupational pneumoconiosis from 2012 to 2021 in Sichuan Province were collected from the Occupational Diseases and Hazards Monitoring Information System under China Disease Prevention and Control Information System, and were analyzed retrospectively. Results: From 2012 to 2021, there were 30 136 newly diagnosed occupational pneumoconiosis cases in Sichuan Province. The average age of patients was 55.2 years and the median work age was 12.1 years. There were 6 471 cases (accounting for 21.5%) exposed to dust for less than 5.0 years. The number of the cases declined in newly diagnosed occupational pneumoconiosis and occupational pneumoconiosis with less than 5.0 years of dust exposure. The numbers of coal workers' pneumoconiosis and silicosis were 16 210 and 13 577, respectively (accounting for 98.9% of the total cases). The majority of pneumoconiosis cases were classified as stage Ⅰ(accounting for 67.1%). The cases from Leshan City, Bazhong City, Dazhou City, Yibin City, Guangyuan City and Luzhou City accounted for 68.8% of the total cases. The main types of work were coal miner and excavation worker, which accounted for 31.7% and 18.8%, respectively. The scale of enterprises was mostly small and micro, accounting for 35.1% of the cases, and the industry distribution was mostly coal mining and washing, accounting for 53.4% of the cases. Conclusion: In Sichuan Province, the number of cases shows an overall decline in both newly diagnosed occupational pneumoconiosis and occupational pneumoconiosis with less than 5.0 years of dust exposure, with a relatively short duration of occupational exposure. The key cities for pneumoconiosis prevention and control are Leshan City, Bazhong City, and Dazhou City, while the key industry is coal mining and washing.

Research progress on using traditional Chinese medicine and extracts for activating blood circulation in prevention and treatment of silicosis / 中国职业医学

Occupational silicosis features as irreversible pulmonary fibrosis, which is caused by long-term inhalation of free silica dust. The pathogenesis of silicosis is complex and there is no cure at present. Traditional Chinese medicine classifies silicosis fibrosis into the category of diseases as "pulmonary paralysis" and "pulmonary arthralgia", and its treatment is based on promoting blood circulation and activating qi. Traditional Chinese medicine for activating blood circulation is one of the commonly used medications, which has the effects of anti-oxidation, anti-inflammation, anti-fibrosis and immunomodulation, and has broad application prospect in the prevention and treatment of silicosis. At present, animal experiments and clinical studies have been carried out using the single Chinese herbs extracts that could activate blood circulation such as Salvia miltiorrhiza, Ligusticum chuanxiong Hort., Panax notoginseng, Curcuma longa L., peach kernel and Carthamus tinctorius L. as well as their compound herbs for the prevention and treatment of silicosis. The mechanisms of anti-pulmonary fibrosis and the efficacy and safety of treating silicosis and its complications were explored. There are also scholars studying Salvia miltiorrhiza, Curcuma longa L. and Danhong injection, Taohong Siwu Decoction and others for prevention and treatment of pulmonary fibrosis. Additionally, network pharmacological research, analyzing potential targets and pathways, were carried out to provide scientific rationale for prevention and treatment of silicosis. However, the effectiveness of research is still uncertain, and it cannot meet the clinical needs. In the future, it is necessary to explore the application of more high-quality active components of traditional Chinese medicine monomer or mixture of activating blood circulation in the prevention and treatment of silicosis, to provide new ideas and scientific basis for the prevention and treatment of silicosis using traditional Chinese medicine.

Effect of silicon dioxide exposure on airway surface microenvironment and NEK7/NLPR3 inflammasome in rats / 预防医学

Objective@#To examine the effect of SiO2 exposure on the airway surface microenvironment and NIMA-related kinase 7 (NEK7)/nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome in rats.@*Methods@#Twenty-four specific pathogen-free male rats of the SD strain were randomly divided into the control group and the model group, of 12 rats in each group. Rats in the model group were given SiO2 suspensions through disposable tracheal intubation perfusion to model silicosis in rats, while rats in the control group was perfused with the same amount of physiological saline. The pH value and glucose level were measured in the rat bronchoalveolar lavage fluid (BALF) 14 and 28 days after modeling. Lung tissues were stained with HE and Masson and the distribution of inflammatory cells and the deposition of pulmonary interstitial collagens were observed in lung tissues under a light microscope. The expression of transforming growth factor β1 (TGF-β1), collagen type Ⅰ(ColⅠ), collagen type Ⅲ (Col Ⅲ), interleukin-1β (IL-1β), NLRP3, N-terminal domain of Gasdermin D (GSDMD-NT), caspase-1, and NEK7 was quantified in lung specimens using immunohistochemistry.@*Results@# Lower pH values were measured in rat BALF in the model group than in the control group 14 [(6.38±0.05) vs. (6.68±0.08), P<0.05] and 28 days after modeling [(6.63±0.14) vs. (6.86±0.05), P<0.05], while higher glucose levels were seen in the model group than in the control group 14 [(0.39±0.06) vs. (0.31±0.04) mg/dL, P<0.05] and 28 days after modeling [(0.39±0.08) vs. (0.31±0.06) mg/dL, P<0.05]. HE and Masson staining showed mild to moderate alveolitis and pulmonary fibrosis in rats 14 days post-exposure to SiO2, and showed moderate to severe alveolitis and pulmonary fibrosis 28 days post-exposure. Immunohistochemistry detected higher TGF-β1, ColⅠ, Col Ⅲ, IL-1β, NLRP3, GSDMD-NT, caspase-1 and NEK7 expression in rat lung tissues in the model group than in the control group (all P<0.05). @*Conclusions@#SiO2 exposure may cause changes in rat airway surface microenvironment, including BALF acidification and elevated glucose. Pyroptosis induced by activation of NEK7-associated NLRP3 inflammasome may be an important mechanism of pulmonary fibrosis caused by silicosis.

Protective Effect of Alcohol Extract of Phyllanthi Fructus on Silicosis Mice and Its Correlation with Nrf2/ARE Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo explore the effect and underlying mechanism of alcohol extract of Phyllanthi Fructus on silicosis mice induced by silicon dioxide （SiO2）. MethodThirty-six male Kunming mice of SPF grade were randomly divided into a blank group，a model group，high-， medium， and low-dose Phyllanthi Fructus groups （800， 400， 200 mg·kg-1），and a tetrandrine group （0.039 mg·kg-1），with six mice in each group. The silicosis model was induced by static SiO2 exposure in mice except for those in the blank group. After 28 days of administration by gavage，the lung tissues were collected and the organ coefficient was calculated. Hematoxylin-eosin（HE）staining and Masson staining were used to detect the morphology of lung tissues. The content of hydroxyproline （HYP），superoxide dismutase （SOD），malondialdehyde （MDA）， and catalase （CAT） in serum was detected by enzyme-linked immunosorbent assay （ELISA）. Western blot and Real-time polymerase chain reaction（Real-time PCR） were used to detect the protein and mRNA expression of nuclear factor E2-related factor 2 （Nrf2），heme oxygenase-1 （HO-1），NAD（P）H：quinone oxidoreductase 1 （NQO1），and Kelch-like ECH-associated protein 1 （Keap1）， respectively. ResultCompared with the blank group，the model group showed seriously damaged morphological structure of lung tissues with inflammatory cell infiltration and fibrous tissue proliferation， reduced serum content of SOD and CAT（P<0.01），increased content of HYP and MDA（P<0.01）， down-regulated protein and mRNA expression of Nrf2，HO-1， and NQO1（P<0.01），and up-regulated protein and mRNA expression of Keap1 （P<0.05，P<0.01）. Compared with the model group，the high- and medium-dose Phyllanthi Fructus groups showed significantly restored morphological structure of lung tissues with reduced collagen deposition， increased serum content of SOD and CAT（P<0.05，P<0.01），decreased content of HYP and MDA（P<0.01）， up-regulated protein and mRNA expression of Nrf2，HO-1， and NQO1 （P<0.05，P<0.01），and down-regulated protein and mRNA expression of Keap1（P<0.05，P<0.01）. ConclusionThe alcohol extract of Phyllanthi Fructus can inhibit pulmonary fibrosis in silicosis mice，and the underlying mechanism may be related to the regulation of the Nrf2/antioxidant response element （ARE） signaling pathway.

Meta-analysis of Ac-SDKP inhibition of Pulmonary fibrosis in animal models / 中华劳动卫生职业病杂志

Objective: To systematically study the anti-fibrotic effect of N-acetyl-seryl-as partyl-lysyl-proline (Ac-SDKP) on pulmonary fibrosis. Methods: In May 2021, a computer search was performed on CNKI, Wanfang Knowledge Service Platform, VIP.com, China Biomedical Literature Database, Pubmed, OVID and other databases. The retrieval time was from January 2008 to May 2021. Randomized controlled experiments on the inhibition of pulmonary fibrosis by Ac-SDKP were screened. The control group was the pulmonary fibrosis model group and the experimental group was the Ac-SDKP treatment group. The quality of the literature was assessed using the syrcle risk of bias assessment tool, and data were extracted. Data analysis was Performed using revman 5.4 software. Results: 18 papers were included, with a total of 428 animal models. The results of meta analysis showed that the contents of α-smooth muscle actin (α-SMA), type I collagen, type Ⅲ collagen, transforming growth factor-β (TGF-β) and Nodule area in the exPerimental group were lower than those in the control grouP. [SMD=-2.44, 95%CI (-3.71--1.17), P=0.000][SMD=-5.36, 95%CI (-7.13--3.59), P=0.000] [SMD=-3.07, 95%CI (-4.13--2.02), P<0.000][SMD=-2.88, 95%CI (-3.63--2.14), P=0.000] [SMD=-1.80, 95%CI (-2.42--1.18), P=0.000], the content of hydroxy proline in the experimental group was higher than that in the control group [SMD=7.62, 95%CI (4.90-10.33), P=0.000], all indexes included in the literature were statistically significant. Conclusion: Ac-SDKP has obvious inhibitory effect on the process of pulmonary fibrosis, and may become a new clinical drug for the treatment of pulmonary fibrosis.

A systematic review of the epidemiology and clinical characteristics of artificial stone-related silicosis and dust protection / 中华劳动卫生职业病杂志

Objective: To investigate the epidemiology, clinical characteristics, on-site dust monitoring and individual protection of the patients with artificial stone-related silicosis. Methods: In March 2022, the literature on artificial stone-related silicosis published from January 1965 to February 2022 was searched in China Journal Full-text Database, Wanfang Database, VIP Database, EMbase and PubMed. Chinese and English search terms include "silica dust""silica dust""silicosis""artificial stone""pneumoconiosis", etc. References were included according to inclusion and exclusion criteria, and data were extracted. The epidemiological characteristics, natural course of disease, workplace dust concentration and individual protection level of patients with artificial stone-related silicosis were analyzed by systematic review. Results: A total of 30 literatures were included, including 7 cohort studies, 14 cross-sectional studies, 3 case-control studies and 6 case reports. A total of 1358 patients with artificial stone-related silicosis were diagnosed from 1997 to 2020, with an average age of 41.5 years old and an average dust exposure time of 11.3 years. Among them, 36.2% (282/778) had progressive mass fibrosis or accelerated progressive silicosis at first diagnosis. Chest imaging showed diffuse small nodule shadow, pulmonary fibrosis, and silico-alveolar proteinosis. Pulmonary function showed restricted or mixed ventilation disorder with or without decreased diffusion volume. The disease progressed rapidly, with progressive mass fibrosis, respiratory failure, and even death. Patients engaged in artificial quartz stone processing, with high concentration of silica including ultra-fine particles, most of which were dry operation, lack of on-site ventilation measures and no effective personal protection. Conclusion: The artificial stone processing workers suffer from artificial stone-related silicosis due to dry cutting, lack of on-site dust removal facilities and personal protective measures, and the disease progresses rapidly, leading to poor prognosis.

Evaluation of right ventricular function using two-dimensional speckle tracking echocardiography and analysis of the risk factors for right ventricular dysfunction in patients with silicosis / 中华劳动卫生职业病杂志

Objective: To evaluate the right ventricular function using two-dimensional speckle tracking echocardiography (2-D STE) and analyze the associated risk factors of right ventricular dysfunction in patients with silicosis. Methods: All 104 patients with silicosis treated in the Department of Occupational Medicine and Toxicology in Beijing Chao-Yang Hospital, Capital Medical University from May 2021 to September 2022 were enrolled in this study in October 2022. The clinical information of patients such as general data, arterial blood gas analysis and pulmonary function test were collected. The right ventricular function of patients was evaluated by 2-D STE-derived right ventricular free wall longitudinal strain (RVFWLS) and conventional echocardiographic-derived parameters, including right ventricular fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE) and doppler tissue imaging-derived tricuspid lateral annular systolic velocity (S'), respectively. Based on their RVFWLS, the patients were divided into right ventricular dysfunction group and normal right ventricular function group. Risk factors for right ventricular dysfunction in patients with silicosis were analyzed using binary logistic regression analysis. Results: A total of 104 silicosis patients were enrolled, with aneverage age (65.52±11.18) years old, among whom including 57 cases diagnosed with stage Ⅰ/Ⅱ silicosis and 47 cases diagnosed with stage Ⅲ silicosis. 26 (25.00%) patients concurrent right ventricular dysfunction. The abnormal rates of RVFAC, TAPSE and S' in patients were 16.35% (17 cases), 21.15% (22 cases) and 6.73% (7 cases), respectively. The RVFAC and TAPSE in right ventricular dysfunction group were lower than those in normal right ventricular function group, and the incidence of pulmonary arterial systolic pressure ≥36 mmHg was higher than that in normal right ventricular function group (P<0.05). Logistic regression analysis showed that arterial partial pressure of oxygen (OR=0.932, 95%CI: 0.885-0.981, P=0.007) was the protective factor, and the forced expiratory volume in 1 second (FEV(1)) /forced vital capacity (FVC) ratio<70% (OR=5.484, 95%CI: 1.049-28.662, P=0.044) and stage Ⅲ silicosis (OR=6.343, 95%CI: 1.698-23.697, P=0.007) were the risk factors for silicosis patients concurrent right ventricular dysfunction. Conclusion: The incidence of right ventricular dysfunction is higher in patients with stage Ⅲ silicosis than that in patients with stage Ⅰ/Ⅱ silicosis. Using 2-D STE can help the early detection of silicosis with right ventricular dysfunction. Hypoxemia, airflow limitation and the stage Ⅲ silicosis are the risk factors for silicosis patients concurrent right ventricular dysfunction.

Epidemiological characteristics of pneumoconiosis deaths in a certain area from 1961 to 2020 / 中华劳动卫生职业病杂志

Objective: To investigate the epidemiological characteristics of pneumoconiosis deaths in Putuo District of Shanghai, and to provide evidence for prevention and management of pneumoconiosis in the future. Methods: In June 2021, the data of 263 patients with pneumoconiosis who died from January 1961 to December 2020 in Putuo District of Shanghai were retrospectively analyzed. Trend χ(2) test, analysis of variance and Spearman rank correlation methods were used to analyze the basic information, age of exposure to dust, promotion period, course of disease and direct cause of death of patients with pneumoconiosis. Results: Among the 263 cases of pneumoconiosis patients who died in Putuo District of Shanghai from 1961 to 2020, 260 cases (98.86%) were male. The main types of pneumoconiosis were foundry worker pneumoconiosis (53.23%, 140/263) and silicosis (43.73%, 115/263). The main types of pneumoconiosis were sand cleaner (36.50%, 96/263). The age of onset was (53.42±10.13) years old, the age of death was (76.14±9.12) years old, and the age of exposure to dust was (20.91±8.99) years. The duration of dust exposure was negatively correlated with the duration of disease (r(s)=-0.24, P<0.001). With the increase of pneumoconiosis stage, the mortality of silicosis and foundry worker pneumoconiosis also showed an increasing trend (χ(2)(trend)=4.22, 3.87, P=0.040, 0.049). 31.94% (84/263) of pneumoconiosis patients died directly from pneumoconiosis, ranking first among the direct causes of death. Conclusion: The death cases of pneumoconiosis in Putuo District of Shanghai are mainly foundry worker pneumoconiosis and silicosis, and pneumoconiosis is the main cause of death.