Modification of m6 A in human embryonic lung fibroblasts induced by neodymium oxide exposure and its mechanism / 环境与职业医学

Background Occupational and environmental particulate matter may cause fibrosis, accompanied by RNA m6A modification changes. Neodymium oxide (Nd2O3) can cause mouse lung fibrosis, which contains a large number of fibroblasts. Objective To investigate m6A modification of tumor necrosis factor receptor-associated protein 6/nuclear factor-κB (TRAF6/NF-κB) signaling pathway in fibrosis of human embryonic lung fibroblasts induced by Nd2O3, and identify the key m6A modification sites of TRAF6. Methods Designed concentrations of Nd2O3 (0, 1.563, 3.125, 6.25, 12.5, 25, 50, 100, and 200 mg∙L−1) were infected with HELF cells for 24 and 48 h, and cell viability was detected to determine exposure time and dose. Measurements included indicators of fibrosis [hydroxyproline (HYP) and transforming growth factor-β1 (TGF-β1)], m6A methylation level, methyltransferases (METTL3 and METTL14), demethylases (FTO and ALKBH5), reading proteins (YTHDC2 and YTHDF2), fibrosis-associated genes (collagen-І, vimentin, and α-SMA), and proteins related to signaling pathway (TRAF6, NFKB1, P65, and P-P65). The enrichment of m6A in TRAF6 mRNA was measured by methylated RNA immunoprecipitation-quantitative real-time PCR (MeRIP-qPCR). Results The results of cell viability indicated that 6.25, 12.5, 25 mg∙L−1 Nd2O3 and 48 h exposure time were used for subsequent experiments. After 48 h exposure, compared with the control group, the HYP level in the 25 mg∙L−1 Nd2O3 group was increased, and the levels of TGF-β1 in the 6.25, 12.5, and 25 mg∙L−1 Nd2O3 groups were increased (P<0.05); the overall m6A methylation levels of HELF cells in the 12.5 and 25 mg∙L−1 Nd2O3 groups were increased (P<0.05). At mRNA level, compared with the control group, the mRNA expression levels of methyltransferases METTL3 and METTL14 (6.25, 12.5, and 25 mg∙L−1 Nd2O3) were increased (P<0.05); the mRNA expression level of reading protein YTHDF2 (6.25, 12.5, and 25 mg∙L−1 Nd2O3) was increased (P<0.05), while the mRNA expression level of YTHDC2 (25 mg∙L−1 Nd2O3) was decreased (P<0.05); the mRNA expression levels of demethylases FTO (12.5 and 25 mg∙L−1 Nd2O3) and ALKBH5 (25 mg∙L−1 Nd2O3) were decreased (P<0.05); the mRNA expression levels of fibrosis-related genes vimentin, α-SMA, and collagen-Ⅰ (6.25, 12.5, and 25 mg∙L−1 Nd2O3) were increased (P<0.05); the mRNA expression levels of pathway-related genes TRAF6 (25 mg∙L−1 Nd2O3) and NFKB1 (12.5 and 25 mg∙L−1 Nd2O3) were increased (P<0.05). At protein level, compared with the control group, the expression levels of methyltransferases METTL3 (25 mg∙L−1 Nd2O3) and METTL14 (12.5 and 25 mg∙L−1 Nd2O3) were increased (P<0.05); the expression level of reading protein YTHDF2 (12.5 and 25 mg∙L−1 Nd2O3) was increased, while the expression level of YTHDC2 (25 mg∙L−1 Nd2O3) was decreased (P<0.05); the expression level of demethylase FTO (25 mg∙L−1 Nd2O3) was decreased (P<0.05); the expression level of fibrosis-associated protein vimentin was increased at 25 mg∙L−1 Nd2O3, and the expression levels of α-SMA and collagen-Ⅰ were increased at 12.5 and 25 mg∙L−1 Nd2O3 (P<0.05); the expression levels of TRAF6 and P-P65 were increased at 25 mg∙L−1 Nd2O3 (P<0.05). The MeRIP-qPCR results showed that compared with the control group, the concentrations of m6A in all Nd2O3 groups were significantly increased (P<0.05). Conclusions Upon exposure of HELF cells to Nd2O3, the alterations in fibrosis-related indexes increase the expression of some m6A methylases and decrease the expression of demethylases, thereby increasing the m6A methylase level, and may promote the progression of fibrosis by activating the TRAF6/NF-κB signaling pathway.

Changes of m6A modification in arsenic-induced oxidative stress of human embryonic lung fibroblasts / 环境与职业医学

Background Arsenic can be toxic to human by triggering oxidative stress, which is companied by epigenetic modifications. Objective To investigate the modification of N6-methyladenosine (m6A) in human embryonic lung fibroblasts (HELF) during oxidative stress induced by sodium arsenite (NaAsO2). Methods HELF cells were treated by designed concentrations of NaAsO2 (0, 2.5, 5, 10, and 20 μmol·L−1) for 48 h. Cell viability was detected by 3-(4,5-dimethylthia zol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfopheny)-2H-tetrazolium (MTS) method; the activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) as well as the content of malondialdehyde (MDA) were detected with corresponding kits; the level of m6A methylation in total RNA was detected by enzyme-linked immunosorbent assay; the mRNA expressions of m6A modified enzymes were detected by real-time fluorescence quantitative PCR, including methyltransferase-like 3 (METTL3), methyltransferase-like 14 (METTL14), Wilms' tumor 1-associated protein (WTAP), fat mass and obesity-associated protein (FTO), alkB family of Fe(II)/α-ketoglutarate-dependent dioxygenases 5 (ALKBH5), YTH domain containing protein 2 (YTHDC2), YTH domain family protein 2 (YTHDF2), and YTH domain family protein 3 (YTHDF3); the protein expressions of METTL3, FTO, YTHDC2, YTHDF3, and nuclear factor erythroid 2-related factor 2 (NRF2) were detected by Western blotting. The enrichment of m6A in NRF2 mRNA was detected by RNA methylated immunoprecipitation combined with real-time fluorescence quantitative PCR (MeRIP-qPCR). Results After the 0, 2.5, 5, 10, and 20 μmol·L−1 NaAsO2 treatment, the MTS results showed that compared with the control group, the cell viability of the 20 μmol·L−1 group decreased to 84% (P<0.05). The colorimetry results showed that compared with the control group, the activities of T-SOD in the 10 and 20 μmol·L−1 groups decreased (P<0.05); the activities of GSH-Px in the 2.5 and 10 μmol·L−1 groups decreased (P<0.05); the contents of MDA in the 10 and 20 μmol·L−1 groups increased. The results of enzyme-linked immunosorbent assay showed that the overall m6A methylation levels in the 0, 2.5, 5, 10, and 20 μmol·L−1 groups were (0.193 ± 0.023)%, (0.247 ± 0.021)%, (0.253 ± 0.006)%, (0.233 ± 0.006)%, and (0.262 ± 0.010)%, respectively, and compared with the control group, the m6A methylation levels in all the NaAsO2 treated groups increased (P<0.05). The real-time fluorescence quantitative PCR results showed that compared with the control group, the mRNA relative expression level of METTL3 decreased in the 2.5, 10, and 20 μmol·L−1 groups (P<0.05); the mRNA relative expression level of FTO decreased in the 20 μmol·L−1 group; the mRNA relative expression level of YTHDC2 increased in the 10 and 20 μmol·L−1 groups (P<0.05); the mRNA relative expression level of YTHDF3 increased in the 2.5, 10, and 20 μmol·L−1 groups (P<0.05). The Western blotting results showed that compared with the control group, the relative protein expression of METTL3 decreased in the 10 and 20 μmol·L−1 groups; the relative protein expression of FTO decreased in the 5 and 20 μmol·L−1 groups; the relative protein expression of YTHDC2 decreased in the 20 μmol·L−1 group (P<0.05); the relative nuclear protein expression of NRF2 decreased in the 10 and 20 μmol·L−1 groups (P<0.05). The MeRIP-qPCR results showed that m6A enrichment was significantly increased in the 20 μmol·L−1 NaAsO2 exposure group compared with the control group (P<0.05). After over-expression of FTO, the mRNA and protein relative expression levels of FTO and the relative expression level of nuclear protein of NRF2 in the FTO group were higher than those in the control group (P<0.05); the mRNA and protein relative expression levels of FTO in the NaAsO2 + FTO group and the nuclear protein expression level of NRF2 were higher than those in the NaAsO2 group (P<0.05). Conclusion In the process of oxidative stress induced by NaAsO2, m6A methylation level, m6A modified enzymes, m6A modification of NRF2 mRNA, and NRF2 expression could change in HELF cells.

Overexpression of mitofusion 2 inhibits acute respiratory distress syndrome pulmonary fibrosis and its mechanism / 中华危重病急救医学

Objective:To study the inhibitory effect of overexpression of mitofusion 2 (Mfn2) protein on acute respiratory distress syndrome (ARDS) pulmonary fibrosis and its mechanism.Methods:Human embryo lung fibroblasts (HELF) were cultured in vitro, and digested and passaged when the adherent rate of HELF reached 80%, and then the cells in good condition were selected for experiment. The ARDS cell model was reproduced by 5 mg/L of lipopolysaccharide (LPS, LPS group); 75 mol/L adenovirus vector carrying mitofusion 2 (Adv-Mfn2) was transfected into HELF (Adv-Mfn2+LPS group); at the same time, blank control group (complete medium culture) and Adv-vector+LPS group were set as controls. The cell proliferation was observed by sulforhodamine B (SRB) method at 0, 12, 24, 36 and 48 hours. After Hoechst 33342 staining, the morphological changes were observed under confocal microscope. Western blotting was used to detect the protein expressions of Bcl-2 and caspase-3. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) was used to detect the gene expressions of Bcl-2 and caspase-3. Results:After LPS stimulation for 12-48 hours, the cell proliferation rates in the LPS group increased gradually, which were significantly higher than those in the blank control group [12 hours: (10.75±1.51)% vs. (0.73±1.22)%, 24 hours: (20.09±1.71)% vs. (1.15±1.12)%, 36 hours: (20.58±1.55)% vs. (1.20±1.12)%, 48 hours: (21.30±1.51)% vs. (1.23±1.10)%, all P < 0.01]. There was no statistically significant difference in the cell proliferation rate between the LPS group and the Adv-vector+LPS group. After overexpression of Mfn2, the cell proliferation rates at 12, 24, 36, 48 hours in the Adv-Mfn2+LPS group were (8.93±1.14)%, (10.52±1.24)%, (10.72±1.30)%, and (10.91±1.20)%, which were significantly lower than those in the LPS group (all P < 0.05). Confocal microscopy showed that some cells in the blank control group had nuclei of different sizes, and some nuclei fragmented or shrank to form apoptotic bodies. The nuclei of the cells in the LPS and Adv-vector+LPS groups were round or oval in size, and only a few apoptotic cells appeared. When Mfn2 was overexpressed, there were more apoptotic cells in the visual field in the Adv-Mfn2+LPS group than LPS group. Western blotting and RT-qPCR results showed that Bcl-2 expressions increased significantly after LPS stimulation in the LPS group as compared with the blank control group [Bcl-2 protein (Bcl-2/GAPDH): 0.68±0.01 vs. 0.29±0.01, Bcl-2 mRNA (2 -ΔΔCT): 2.23±0.34 vs. 1.00±0.00, both P < 0.01], and caspase-3 expressions decreased significantly [caspase-3 protein (caspase-3/GAPDH): 0.37±0.02 vs. 0.66±0.02, caspase-3 mRNA (2 -ΔΔCT): 0.31±0.05 vs. 1.00±0.00, both P < 0.01]. Compared with LPS group, the expressions of Bcl-2 after overexpression of Mfn2 in the Adv-Mfn2+LPS group were down-regulated [Bcl-2 protein (Bcl-2/GAPDH): 0.46±0.01 vs. 0.68±0.01, Bcl-2 mRNA (2 -ΔΔCT): 1.45±0.14 vs. 2.23±0.34, both P < 0.01], and the expressions of caspase-3 were up-regulated [caspase-3 protein (caspase-3/GAPDH): 0.54±0.02 vs. 0.37±0.02, caspase-3 mRNA (2 -ΔΔCT): 0.88±0.10 vs. 0.31±0.05, both P < 0.01]. Conclusion:Mfn2 protein is involved in ARDS pulmonary fibrosis, which may be related to mitochondrial mediated inhibition of cell proliferation.

Anti-senescence effect and molecular mechanism of the major royal jelly proteins on human embryonic lung fibroblast (HFL-I) cell line / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Royal jelly (RJ) from honeybee has been widely used as a health promotion supplement. The major royal jelly proteins (MRJPs) have been identified as the functional component of RJ. However, the question of whether MRJPs have anti-senescence activity for human cells remains. Human embryonic lung fibroblast (HFL-I) cells were cultured in media containing no MRJPs (A), MRJPs at 0.1 mg/ml (B), 0.2 mg/ml (C), or 0.3 mg/ml (D), or bovine serum albumin (BSA) at 0.2 mg/ml (E). The mean population doubling levels of cells in media B, C, D, and E were increased by 12.4%, 31.2%, 24.0%, and 10.4%, respectively, compared with that in medium A. The cells in medium C also exhibited the highest relative proliferation activity, the lowest senescence, and the longest telomeres. Moreover, MRJPs up-regulated the expression of superoxide dismutase-1 (SOD1) and down-regulated the expression of mammalian target of rapamycin (MTOR), catenin beta like-1 (CTNNB1), and tumor protein p53 (TP53). Raman spectra analysis showed that there were two unique bands related to DNA synthesis materials, amide carbonyl group vibrations and aromatic hydrogens. These results suggest that MRJPs possess anti-senescence activity for the HFL-I cell line, and provide new knowledge illustrating the molecular mechanism of MRJPs as anti-senescence factors.

Mormorphological and functional changes of lung cells in hyperoxia environment / 中华危重病急救医学

Objective To observe the morphological and functional changes of different lung cells in hyperoxia environment.Methods Type Ⅱ alveolar epithelial cells (AECⅡ) and lung fibroblasts (LFs) of fetal rats with 18 days old were isolated and culturedin vitro, and divided into air group (placed in an atmospheric incubator, and culturing with oxygen volume fraction of 0.21) and hyperoxia group (placed in a high oxygen culture chamber, and culturing with oxygen volume fraction of 0.90). Morphological changes of two kinds of cells were observed under microscope. Cell migration was observed by scratch test. The levels of reactive oxygen species (ROS) and apoptosis in cells were detected by flow cytometry.Results After 8 hours of hyperoxia, the volume of AECⅡincreased and the cells were loosely arranged; the clearance of LFs cells was increased and arranged in disorder. Scratch test showed that, compared with air group, the immigration rate of AECⅡ was inhibited at 6 hours hyperoxia [migration rate: (38.67±1.15)％ vs. (58.67±2.31)％,P < 0.01], the immigration rate of LFs was promoted at 12 hours after hyperoxia [migration rate:(55.37±1.50)％ vs. (46.90±1.20)％,P < 0.01]. With the increase of hyperoxia time, intracellular ROS contents of two cells were gradually increased, which were significantly higher than those of the air group (fluorescence intensity:130.67±4.04 vs. 54.67±2.51, 85.00±2.00 vs. 60.33±1.52, bothP < 0.01). Both two kinds of cells showed apoptosis after exposure to high oxygen, the apoptosis rate of AECⅡ at 2 hour exposure were significantly higher than that of air group [(1.93±0.28)％ vs. (1.07±0.11)％,P < 0.05], the apoptosis rate of LFs at 6 hour exposure was significantly higher than that of air group [(1.66±0.09)％ vs. (1.46±0.09)％,P < 0.05].Conclusion High concentration of oxygen can cause poor growth of lung cells, reduce AEC Ⅱ migration level and increase LFs migration, and the production of intracellular ROS eventually leads to apoptosis of lung cells.

Dust particles-induced intracellular Ca²⁺ signaling and reactive oxygen species in lung fibroblast cell line MRC5

Epidemiologic interest in particulate matter (PM) is growing particularly because of its impact of respiratory health. It has been elucidated that PM evoked inflammatory signal in pulmonary epithelia. However, it has not been established Ca²⁺ signaling mechanisms involved in acute PM-derived signaling in pulmonary fibroblasts. In the present study, we explored dust particles PM modulated intracellular Ca²⁺ signaling and sought to provide a therapeutic strategy by antagonizing PM-induced intracellular Ca²⁺ signaling in human lung fibroblasts MRC5 cells. We demonstrated that PM10, less than 10 µm, induced intracellular Ca²⁺ signaling, which was mediated by extracellular Ca²⁺. The PM10-mediated intracellular Ca²⁺ signaling was attenuated by antioxidants, phospholipase blockers, polyADPR polymerase 1 inhibitor, and transient receptor potential melastatin 2 (TRPM2) inhibitors. In addition, PM-mediated increases in reactive oxygen species were attenuated by TRPM2 blockers, clotrimazole (CLZ) and N-(p-amylcinnamoyl) anthranilic acid (ACA). Our results showed that PM10 enhanced reactive oxygen species signal by measuring DCF fluorescence and the DCF signal attenuated by both TRPM2 blockers CLZ and ACA. Here, we suggest functional inhibition of TRPM2 channels as a potential therapeutic strategy for modulation of dust particle-mediated signaling and oxidative stress accompanying lung diseases.

Activity of Baicalin Against Human Cytomegalovirus In Vitro and Its Effect on the Apoptosis of Human Embryo Lung Fibroblasts Infected with Human Cytomegalovirus / 医药导报

Objective To elucidate activity of baicalin against human cytomegalovirus ( HCMV) in vitro, and explore its effect on apoptosis of human embryo lung fibroblasts ( HEL ) infected with HCMV. Methods CCK-8 kit was used to determine the maximum tolerated dose ( MTC ) of HEL cell to baicalin while the anti-HCMV median efficacious concentration ( EC50 ) of baicalin was determined by standard plaque reduction method. After treatment with baicalin of different concentrations for 24, 48, 72 and 96 h, cell apoptosis and pro-caspase-3 expression was detected by flow cytometry and Western blotting, respectively. Results The MTC of baicalin was 20.6 μg?mL-1; The EC50 of anti-HCMV of baicalin was 16.13 μg?mL-1;The apoptosis rate increased gradually in the groups with low and high multiplicity HCMV infection at early time, showing significant dose-dependent manner. While the ratio of apoptotic cells was going to decrease in high multiplicity infection group 96 h after the infection. The expression of pro-caspase-3 was significantly higher in high-dose baicalin treatment group than in the infection control group ( P<0.05) . Conclusion Baicalin has a direct anti-HCMV effect in vitro. One of the mechanisms might be related with it inhibiting cell apoptosis and antagonizing activation of pro-caspase-3.

Activity of Baicalin Against Human Cytomegalovirus In Vitro and Its Effect on the Apoptosis of Human Embryo Lung Fibroblasts Infected with Human Cytomegalovirus / 医药导报

Objective To elucidate activity of baicalin against human cytomegalovirus ( HCMV) in vitro, and explore its effect on apoptosis of human embryo lung fibroblasts ( HEL ) infected with HCMV. Methods CCK-8 kit was used to determine the maximum tolerated dose ( MTC ) of HEL cell to baicalin while the anti-HCMV median efficacious concentration ( EC50 ) of baicalin was determined by standard plaque reduction method. After treatment with baicalin of different concentrations for 24, 48, 72 and 96 h, cell apoptosis and pro-caspase-3 expression was detected by flow cytometry and Western blotting, respectively. Results The MTC of baicalin was 20.6 μg?mL-1; The EC50 of anti-HCMV of baicalin was 16.13 μg?mL-1;The apoptosis rate increased gradually in the groups with low and high multiplicity HCMV infection at early time, showing significant dose-dependent manner. While the ratio of apoptotic cells was going to decrease in high multiplicity infection group 96 h after the infection. The expression of pro-caspase-3 was significantly higher in high-dose baicalin treatment group than in the infection control group ( P<0.05) . Conclusion Baicalin has a direct anti-HCMV effect in vitro. One of the mechanisms might be related with it inhibiting cell apoptosis and antagonizing activation of pro-caspase-3.

Effects of mycophenolate mofetil on transdifferentiation and function of lung fibroblasts / 中国免疫学杂志

Objective:To investigate the effects of mycophenolate mofetil ( MMF) on the differentiation and connective tissue growth factor(CTGF)and fibronectin(FN)expression of lung fibroblasts(LF)through interfering the transdifferentiation of LF into MF in vitro.Methods:LF of neonatal rat were cultured in vitro ,induced into MF by transforming growth factor-β1(TGF-β1),and treated with different concentrations of MMF ,which was 0μmol/L(control group),0.1μmol/L(low dose group),1μmol/L(middle dose group)or 10 μmol/L( high dose group ) .Morphology of LF and MF were observed by inverted phase contrast microscope , the expressions of vimentin and α-smooth muscle actin (α-SMA) were identified by immunofluorescence staining ,and then analyzed the effect of MMF on the transdifferentiation of fibroblasts .ELISA was used to detect the levels of connective tissue growth factor ( CTGF ) and fibronectin ( FN) .Results: LF was induced into MF by TGF-β196 hours later.The immune fluorescence performance of α-SMA in the lung fibroblasts revealed MMF could suppress the expression of α-SMA,but had no effect on the phenotype of myofibroblasts .The results of ELISA showed that the levels of CTGF and FN were significantly decreased compar with that of control group and was concentration -de-pendent ( P<0.05 ) .Conclusion: MMF can prevent lung fibroblasts from transdifferentiating into myofibroblasts and inhibit the expressions of CTGF and FN ,suggesting that MMF has anti-fibrosis effect and one of the mechanisms is by suppressing the expressions of CTGF and FN.

Effects of DNA methylation of thymocyte differentiation antigen-1 in beryllium sulfate induced human fetal lung fibroblast fibrosis / 中国职业医学

OBJECTIVE: The change of DNA methylation of thymocyte differentiation antigen-1( Thy-1) was observed in beryllium sulfate( Be SO4) stimulated human fetal lung fibroblast( MRC-5 cell) to explore the effects of Thy-1 in Be SO4 induced lung fibrosis. METHODS: MRC-5 cell culture in vitro model was used. The final concentrations of Be SO4were1. 0,10. 0 and 100. 0 μmol / L( low-,medium- and high-dose groups). The control was untreated. Other 2 intervention groups were the 5-azacytidine( AZC) intervention group( 10. 0 μmol / L of AZC and 10. 0 μmol / L Be SO4) and the trichostatin A( TSA) intervention group( 0. 5 μmol / L of TSA and 10. 0 μmol / L Be SO4). The cells were collected 24,48 and 72 hours after exposure. Real-time quantitative polymerase chain reaction( PCR) was used to determine the relative expression of collagen typeⅠ( Col Ⅰ),collagen type Ⅲ( Col Ⅲ),α-smooth muscle actin( α-SMA) and Thy-1 mRNA.The nested landed methylation specific PCR was used to detect the Thy-1 DNA methylation level. RESULTS: At 24 hours,the relative expression level of Col Ⅲ mRNA in MRC-5 cells showed an increasing trend with increasing dose( P < 0. 05);at 48 and 72 hours,the relative expression levels of Col Ⅰ,Col Ⅲ and α-SMA mRNA in MRC-5 cells increased with the increasing dose( P < 0. 05). All these 3 indicators in MRC-5 cells of 3 dose groups increased with the increase of expose time( P < 0. 05). The relative expression level of Thy-1 mRNA in MRC-5 cells of all 3 dose groups were lower than that in control( P < 0. 05). The relative expression level of Thy-1 mRNA of the high-dose group was lower than that of the lowdose group( P < 0. 05). The Thy-1 DNA methylation levels in the medium- and high-dose groups were both higher than that of the control( P < 0. 05). The Thy-1 DNA methylation levels of the 3 dose groups increased with the increasing dose( P < 0. 05). The Thy-1 DNA methylation levels of MRC-5 cells in the 2 intervention groups were higher than that of the control( P < 0. 05),but there was no significant difference when compared with the medium-dose group( P > 0. 05).CONCLUSION: Be SO4 stimulation can induce the fibrosis of MRC-5 cells. In this process,the Thy-1 DNA methylation level increases,while the Thy-1 mRNA expression level decrease. Thy-1 DNA methylation might be one of the important mechanisms of lung fibrosis induced by Be SO4.

Mechanism of beryllium sulfate-induced apoptosis in human embryonic lung fibroblast / 中国职业医学

OBJECTIVE: To investigate the effect of beryllium sulfate( BeSO_4) on apoptosis of human embryonic lung fibroblast( MRC-5 cell). METHODS: MRC-5 cells were cultured in vitro and randomly divided into 6 groups: a control group,a low-,medium- and high-dose BeSO_4 group,an antagonist group,and an activator group. The former 4 groups were given final concentrations of 0,1,10 and 100 μmol / L of BeSO_4,respectively. The combined treatment of BeSO_4and2-aminoethoxydiphenyl borate( 10 μmol / L final concentration) was used in the antagonist group. The combined treatment of BeSO_4 and inositol triphosphate( IP3)( 10 μmol / L final concentration) was used in the activator group. After 24 and48 hours of culture,the cells were harvested. The apoptosis of MRC-5 cells was detected by flow cytometry. The intracellular calcium ion( Ca~(2+)) was detected using laser scanning confocal microscope. Quantitative real-time polymerase chain reaction was used to detect the relative expression of IP_3RⅢ and B-cell lymphoma-2( BCL-2) mRNA and the protein expression of IP_3RⅢ and IP3 were detected by enzyme-linked immunosorbent assay. RESULTS: The apoptosis rates of cells in the 3 BeSO_4 dose groups at the time points of 24 and 48 hours were lower than those in the control group at the same time points( P < 0. 05). The apoptosis rate of the antagonist group was lower than those in medium-dose BeSO_4 group and control group at the same time points( P < 0. 05). At the time point of 48 hours,the apoptosis rate of the activator group was lower than that of control group( P < 0. 05) and higher than that of the medium-dose BeSO_4group( P < 0. 05). As for the Ca~(2+)concentration at time point of 24 hours,the low-dose BeSO_4 group was lower than the control group( P < 0. 05),and the high-dose BeSO_4 group was higher than the control group( P < 0. 05). The Ca~(2+)concentrations at time point of 48 hours in the medium- and high-dose BeSO_4 groups were lower than that in the control group( P < 0. 05). Compared with the medium-dose BeSO_4 group and control group at time points of 24 and 48 hours,the Ca~(2+)concentrations in the antagonist group decreased( P < 0. 05),while thoes of the activator group increased( P < 0. 05). The expression of BCL-2and IP_3RⅢmRNA in the 3 BeSO_4 groups,the activator and antagonist group were higher than those of the control group( P <0. 05). The expression of IP3 R Ⅲ protein at the time point of 24 hours in the medium-dose BeSO_4 group,the activator group and the antagonist group were lower than that of control group( P < 0. 05). The expression of IP_3RⅢ protein at the time point of 48 hours,the high-dose BeSO_4 group was lower than the control group( P < 0. 05); the activator and antagonist groups were higher than the medium-dose BeSO_4group( P < 0. 05). The expression of IP3 protein in the lowand medium-dose BeSO_4 groups and the activator group were higher than that in the control group( P < 0. 05). The expression of IP3 protein in activator group was higher than the medium-dose group( P < 0. 05). CONCLUSION: BeSO_4 might change the Ca~(2+)concentration and inhibite the apoptosis of MRC-5 cell through regulating the IP3 R / Ca~(2+)pathway,IP3 can improve the decrease of Ca~(2+)concentration in MRC-5 cells induced by BeSO_4.

Effect of Salvia miltiorrhiza injection on proliferation, apoptosis and expression of amino acid in human embryonic lung fibroblast cells / 实用医学杂志

Objective To investigate the effect of Salvia miltiorrhiza injection on proliferation , apoptosis and expression of hydroxyproline in human embryonic lung fibroblast cells. Methods TGF-β1 was administered to induce the proliferation in human embryonic lung fibroblast cells; the effect of Salvia miltiorrhiza injection on the number of human embryonic lung fibroblast cells was detected by MTT method; ki67 expression by immunocytochemical method;cell apoptosis by flow cytometry and the expression of hydroxyproline by colorimetry method. Results TGF-β1(0, 2.5, 5, 10, 20, 40 μg/L)could up-regulate cell number of human embryonic lung fibroblast cells in a dose-dependent manner , while the OD value of human embryo lung fibroblasts cells declined pretreated with Salvia miltiorrhiza injection in a dose-dependent manner and Salvia miltiorrhiza injection could induce the apoptosis and down regulated hydroxyproline expression in human embryo lung fibroblasts cells. The results of flow cytometry indicated that cell apoptosis increased after treated with Salvia miltiorrhiza injection when compared with TGF-β1 group (P < 0.05). Meanwhile, Salvia miltiorrhiza injection could down regulate the expression of hydroxyproline (P < 0.01). Conclusions Salvia miltiorrhiza injection can target human embryonic lung fibroblast cells , play a potent role in the airway remodeling through the promotion of its apoptosis and down regulate the expression of hydroxyproline.

Semaphorin 4A enhances lung fibrosis through activation of Akt via PlexinD1 receptor.

Semaphorin 4A plays a regulatory role in immune function and angiogenesis. However, its specific involvement in controlling lung fibrosis, a process that is closely related to angiogenesis and inflammation is still poorly understood. In the present study, we show that treatment of Sema4A on normal lung fibroblasts induces expression of proteins that contribute to a contractile phenotype, including α-smooth muscle actin (α-SMA), ezrin, moesin, and paxillin. We confirm that Sema4A enhances the ability of lung fibroblasts to contract collagen gel. Sema4A treatment led to resistance to apoptosis in normal lung fibroblasts. Relative to normal lung fibroblasts, fibroblasts cultured from scars of patients with the fibrotic disease Systemic Sclerosis (SSc) showed elevated Sema4A secretion, enhanced α-SMA, ezrin, moesin, and paxillin expression, and high ability to induce collagen gel contraction. Using neutralizing antibody against Sema4A receptor, PlexinD1, we found that endogenous Sema4A signalling in SSc fibroblast was through PlexinD1 receptor. We then identified the signalling mechanism through which Sema4A-PlexinD1 promotes the ability of normal fibroblasts to contract a collagen gel matrix. Western blot analysis showed that Sema4A activated the Akt pathway in lung fibroblasts, and the specific inhibitor of Akt pathway, Akt inhibitor III, blocked the ability of Sema4A to promote the ability of lung fibroblasts to contract a collagen gel matrix. Thus, blocking Sema4APlexinD1- Akt cascades might be beneficial in reducing pulmonary fibrosis.

LipoxinA4 reduces lipopolysaccharide-induced expression of cyclooxygenase-2 and prostaglandin E2 in primary lung fibroblasts of rat / 中华急诊医学杂志

Objective To explore the effects of lipoxinA4 on expression of cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2) in rat primary lung fibroblast cells (LF) after lipopolysaccharide (LPS) challenge.Methods Primary lung fibroblast cells were incubated with various concentrations (0.1,1,10 μg/mL) of LPS for different lengths of time (3,6,9 h).Then primary lung fibroblast cells were still incubated in DMEM medium containing LPS in the presence or absence of lipoxinA4.After incubation,the supematant of medium was collected and the level of PGE2 was detected by using ELISA.The cells were harvested,and COX-2 protein was analyzed by Western blot.Results The model of acute inflammation in fibroblasts was well established by administering 1 μg/mL LPS in fibroblasts for 6 hours.Induction of COX-2 protein by LPS was inhibited by lipoxinA4.The levels of PGE2 in control group,LPS group and LPS + LipoxinA4 group were 55.84 pg/mL,411.73 pg/mL and 307.07 pg/mL,respectively,and there was a significantdifference between LPS group and LPS + LipoxinA4 group (P ＜0.01).Conclusion LipoxinA4 down-regulates the expression of the COX-2 induced by LPS in primary lung fibroblast cells and consequently inhibits the production of PGE2 in a dose dependent manner.

Influence of salvianolic acid B on expressions of TGF-β1/Smad signaling pathway related proteins in human lung fibroblasts and its mechanism / 吉林大学学报(医学版)

Objective To investigate the influence of salvianolic acid B on the expressions of TGF-β1/Smad signaling pathway related proteins in human lung fibroblasts,and to explore the mechanism of the inhibitory effect of Sal B on TGF-β1-induced lung fibroblast activation.Methods The human embryonic lung fibroblasts (MRC-5) were cultured in vitro and randomly divided into control group ( the cells were cultured with DMEM without TGF-β1 or Sal B),Sal B group (the cells were cultured with 10μmol·L-1 Sal B),TGF-β1 group (the cells were cultured with 10μg·L-1 TGF-β1),and TGF-β1 (10μg·L-1 )+ Sal B (10μmol·L-1 )group.The protein levels of p-Smad2,p-Smad3,TβRⅠ,and Smad7 in the fibroblasts in various groups were detected by Western blotting method.Results Compared with control group,the expression levels of p-Smad2,p-Smad3,and TβRⅠproteins in TGF-β1 group were significantly increased (P0.05).Compared with TGF-β1 group,the expression levels of p-Smad2,p-Smad3,and TβRⅠ in TGF-β1+ Sal B group were descended (P<0.05),and the expression level of Smad7 was increased (P<0.05).Conclusion Sal B could suppress the TGF-β/Smad signaling pathway in lung fibroblasts and to inhibit the TGF-β1-induced lung fibroblast activation.

Thalidomide inhibits TGF-β1-induced activation of CTGF gene promoter in HELF cell line / 中国病理生理杂志

AIM:To investigate the effects of thalidomide ( THD) on the activation of connective tissue growth factor ( CTGF) gene promoter induced by transforming growth factor β1 ( TGF-β1 ) in human embryonic lung fibroblasts ( HELF) .METHODS:DNA sequence of CTGF gene promoter was cloned into luciferase reporter gene vector to construct the recombinant eukaryotic expression vector pGL 3-CTGFP, and the recombinant vector was transfected into HELF cell line.The effects of TGF-β1 and THD on the activation of CTGF gene promoter were detected by dual-luciferase analysis . RESULTS:TGF-β1 increased the reporter gene activity dose-dependently (P<0.05), with a plateau at 5 μg/L being 2.16 folds as high as the control .TGF-β1-induced increase in the reporter gene activity was also time-dependent ( P<0.05).After exposure to TGF-β1(5 μg/L), the level of luciferase activity reached its peak at 12 h and was 2.52 folds as high as the control .THD significantly inhibited TGF-β1-induced increase in the reporter gene activity in a dose-dependent manner , but its basal activity was not changed .CONCLUSION: TGF-β1 stimulates the transcriptional activity of CTGF gene promoter in HELF cells in a dose-and time-dependent manner , while THD may inhibit the effects dose-dependently .

Influence of Qizhi Yifei Containing Serum on Regulating Expression of MMP-9 and TIMP-1 mRNA in Rat Ffibroblasts Stimulated by TGF-β1 / 中国中医药信息杂志

Objective To observe the influence of Qizhi Yifei containing serum on the expression of MMP-9 and TIMP-1 mRNA in lung fibroblasts, and explore its mechanism. Methods Trypsin digestion method was used to extract fibroblasts from lung tissue in rats. All fibroblasts were cultured and trained to the fourth generation. Then they were randomly divided into control group, model group and drug serum group. The model group and drug serum group were firstly treated by DMEM with 0.002 5 μg/mL TGF-β1. The control group was treated by DMEM only. The control group and model group were then treated by DMEM with blank drug serum in concentration of 5%, and the drug serum group was treated by DEME with Qiahi Yifei containing serum in same concentration. After 48 and 72 hours, RT-PCR was performed to test the expression of MMP-9 mRNA and TIMP-1 mRNA of each group. Results After 48 hours, MMP-9 and TIMP-1 mRNA were significantly increased in model group and drug serum group compared with control group. There was no difference between model group and drug serum group. After 72 hours, MMP-9 mRNA was up-regulated in model group and was decreased in drug serum group compared with control group. There was no significant difference among the three groups on the expression of TIMP-1 mRNA. Conclusion Qizhi Yifei containing serum can decrease the up-regulated expression of MMP-9 mRNA in lung fibroblasts stimulated by TGF-β1.

Dynamic changes of ERK1/2 protein in lung fibroblasts of newborn rats with hyperoxia-induced chronic lung disease / 中华急诊医学杂志

Objective To investigate dynamic changes of extracellular signal regulated protein kinase (ERK) 1/2 in lung fibroblast of newborn rats with chronic lung disease (CLD) caused by hyperoxia.Methods Full-term newborn rats were randomly divided into two groups:air-exposed group and hyperoxia - exposed with 90％ oxygen group.Rats were sacrificed separately 3 d,7 d and 14 days after exposure to air or 90％ oxygen. Then lung fibroblasts of rats were isolated and primarily cultured. By using Immunocystochemistry,Western-blot and RT-PCR methods,the levels of ERK1/2 protein and expressions of ERK1/2 mRNA were measured. Results The levels of p-ERK1/2 protein in lung fibroblast in the hyperoxia group were significant higher on the 7th day and 14th day after exposure to 90％ oxygen compared with those in the air-exposed group (P ＜0.01 ).And the levels of total ERK1/2 protein and expressions of ERK1/2 mRNA did not change noticeably and were not significantly different between two groups (P ＞0.05 ).Conclusions The activation of phosphorated ERK1/2 may lead to lung fibrosis caused by hyperoxia in newborn rats.

Expression of α-smooth muscle actin and collagen I in lung fibroblasts of hyperoxia-exposed newborn rats / 中国小儿急救医学

ObjectiveTo study the expression and the role of α-smooth muscle aetin (α-SMA) and collagen Ⅰ ( Col Ⅰ ) in lung fibroblasts of newborn rats with hyperoxia-induced lung injuries.Methods Thirty full-term newborn Wistar rats were randomly assigned to hyperoxia group (90％ oxygen exposure,n =15 ) and air group (room air exposure,n =15) within 12 h after birth.Then lung fibroblasts were isolated and primary cultured from rat lungs on postnatal 3 d,7 d,and 14 d.The distribution of α-SMA protein were measured by immunohistochemistry.The levels of Col Ⅰ were detected by ELISA.ResultsThere were no significant differences in the levels of α-SMA and Col Ⅰ expressions between the two groups at 3 d ( P＞0.05 ).While the expression of α-SMA ( 112.60 ± 4.61 vs 94.69 ± 2.38,200.30 ± 3.97 vs 103.04 ± 1.91,P＜0.01 ) and Col Ⅰ protein [ ( 28.66 ± 1.15 ) μ.g/L vs ( 24.62 ± 3.15 ) μg/L,( 30.60 ± 0.65 ) μg/L vs (27.46 ± 1.68 ) μg/L,P ＜ 0.05 ] in lung fibroblasts caused by hyperoxia were significantly higher than those in air-exposed group on postnatal 7 d and 14 d.There was positive correlation between α-SMA and Col Ⅰ protein ( r =0.72,P＜0.01 ).ConclusionHyperoxia promotes differentiation of lung fibroblasts into myofibroblasts,and synthesis of type Ⅰ collegen in neonatal rats,which leads to lung fibrosis finally.

Effects of Cigarette Smoke Extract on the Proliferation and Secretion of Hydrogen Peroxide in Human Lung Fibroblasts Induced by Transforming Growth Factor-β1 / 中国呼吸与危重监护杂志

Objective To observe the effects of cigarette smoke extract (CSE) on the proliferation and secretion of hydrogen peroxide (H2O2) in human lung fibroblasts (HLFs) induced by transforming growth faetor-β1(TGF-β1).Methods Cultured HLFs were divided into a normal group and a model group induced by TGF-β1 (5 ng/mL),then intervened with CSE at different concentrations (0% ,2.5% ,5%, 10%, respectively).Brdu ELISA assay was used to detect cell proliferation.H2O2release from cultured cells was assayed using a fluorimetric method.Cellular localization of H2O2 and expression of α-SMA were performed using a fluorescent-labeling strategy.Results TGF-β1 stimulated group showed positive expression of α-SMA, implying TGF-β1 had induced fibroblasts to differentiate into myofibroblasts.In TGF-β1 stimulated group,2.5% and 5% CSE promoted cell proliferation (P < 0.01 or 0.05), while 10% CSE inhibited cell proliferation (P < 0.01).In the normal group, both low and high concentration of CSE inhibited cell proliferation (P < 0.01 or P < 0.05), and the inhibition effect was dose-dependent.HLF induced by TGF-β1 generated low constitutive levels of extracellular H2O2 that was markedly enhanced by CSE treatment (P < 0.01).Pretreatment with DPI, an inhibitor of NADPH oxidase, abolished secretion of H2O2.Cellular localization of H2O2 by a fluorescent-labeling strategy demonstrated that extracellular secretion of H2O2 is specific to the myofibroblast.Conclusions Low concentration of CSE can promote myofibroblast proliferation, and markedly increase extracellular secretion of H2O2.CSE possibly take part in the development and progress of idiopathic pulmonary fibrosis by increasing oxidative stress.