Role of lung ornithine aminotransferase in idiopathic pulmonary fibrosis: regulation of mitochondrial ROS generation and TGF-ß1 activity.

Idiopathic pulmonary fibrosis (IPF) is characterized by aberrant lung remodeling and the excessive accumulation of extracellular matrix (ECM) proteins. In a previous study, we found that the levels of ornithine aminotransferase (OAT), a principal enzyme in the proline metabolism pathway, were increased in the lungs of patients with IPF. However, the precise role played by OAT in the pathogenesis of IPF is not yet clear. The mechanism by which OAT affects fibrogenesis was assessed in vitro using OAT-overexpressing and OAT-knockdown lung fibroblasts. The therapeutic effects of OAT inhibition were assessed in the lungs of bleomycin-treated mice. OAT expression was increased in fibrotic areas, principally in interstitial fibroblasts, of lungs affected by IPF. OAT levels in the bronchoalveolar lavage fluid of IPF patients were inversely correlated with lung function. The survival rate was significantly lower in the group with an OAT level >75.659 ng/mL than in the group with an OAT level ≤75.659 ng/mL (HR, 29.53; p = 0.0008). OAT overexpression and knockdown increased and decreased ECM component production by lung fibroblasts, respectively. OAT knockdown also inhibited transforming growth factor-ß1 (TGF)-ß1 activity and TGF-ß1 pathway signaling. OAT overexpression increased the generation of mitochondrial reactive oxygen species (ROS) by activating proline dehydrogenase. The OAT inhibitor L-canaline significantly attenuated bleomycin-induced lung injury and fibrosis. In conclusion, increased OAT levels in lungs affected by IPF contribute to the progression of fibrosis by promoting excessive mitochondrial ROS production, which in turn activates TGF-ß1 signaling. OAT may be a useful target for treating patients with fibrotic lung diseases, including IPF.

Overexpression of fatty acid synthase attenuates bleomycin induced lung fibrosis by restoring mitochondrial dysfunction in mice.

Proper lipid metabolism is crucial to maintain alveolar epithelial cell (AEC) function, and excessive AEC death plays a role in the pathogenesis of idiopathic pulmonary fibrosis (IPF). The mRNA expression of fatty acid synthase (FASN), a key enzyme in the production of palmitate and other fatty acids, is downregulated in the lungs of IPF patients. However, the precise role of FASN in IPF and its mechanism of action remain unclear. In this study, we showed that FASN expression is significantly reduced in the lungs of IPF patients and bleomycin (BLM)-treated mice. Overexpression of FASN significantly inhibited BLM-induced AEC death, which was significantly potentiated by FASN knockdown. Moreover, FASN overexpression reduced BLM-induced loss of mitochondrial membrane potential and the production of mitochondrial reactive oxygen species (ROS). Oleic acid, a fatty acid component increased by FASN overexpression, inhibited BLM-induced cell death in primary murine AECs and rescue BLM induced mouse lung injury/fibrosis. FASN transgenic mice exposed to BLM exhibited attenuated lung inflammation and collagen deposition compared to controls. Our findings suggest that defects in FASN production may be associated with the pathogenesis of IPF, especially mitochondrial dysfunction, and augmentation of FASN in the lung may have therapeutic potential in preventing lung fibrosis.

Histone deacetylase 3 promotes alveolar epithelial-mesenchymal transition and fibroblast migration under hypoxic conditions.

Epithelial-mesenchymal transition (EMT), a process by which epithelial cells undergo a phenotypic conversion that leads to myofibroblast formation, plays a crucial role in the progression of idiopathic pulmonary fibrosis (IPF). Recently, it was revealed that hypoxia promotes alveolar EMT and that histone deacetylases (HDACs) are abnormally overexpressed in the lung tissues of IPF patients. In this study, we showed that HDAC3 regulated alveolar EMT markers via the AKT pathway during hypoxia and that inhibition of HDAC3 expression by small interfering RNA (siRNA) decreased the migration ability and invasiveness of diseased human lung fibroblasts. Furthermore, we found that HDAC3 enhanced the migratory and invasive properties of fibroblasts by positively affecting the EMT process, which in turn was affected by the increased and decreased levels of microRNA (miR)-224 and Forkhead Box A1 (FOXA1), respectively. Lastly, we found this mechanism to be valid in an in vivo system; HDAC3 siRNA administration inhibited bleomycin-induced pulmonary fibrosis in mice. Thus, it is reasonable to suggest that HDAC3 may accelerate pulmonary fibrosis progression under hypoxic conditions by enhancing EMT in alveolar cells through the regulation of miR-224 and FOXA1. This entire process, we believe, offers a novel therapeutic approach for pulmonary fibrosis.

miRNA-6515-5p regulates particulate matter-induced inflammatory responses by targeting CSF3 in human bronchial epithelial cells.

Particulate matter (PM) is associated with the incidence, exacerbation, and mortality of variable respiratory diseases. However, the molecular mechanisms of PM10-mediated inflammation are unclear. We identified microRNAs (miRNAs) and messenger RNAs (mRNAs) related to the inflammatory response in PM10-exposed bronchial epithelial cells using next-generation sequencing. Of the miRNAs, miR-6515-5p was significantly downregulated in PM10-exposed human bronchial epithelial BEAS-2B cells. miR-6515-5p regulated the production of pro-inflammatory cytokines (IL-6 and IL-8) and the expression of inflammatory genes (IL-1ß, IL-6, IL-8, TNF-α, CXCL-1, and MCP-1) via MAPK/ERK signaling; overexpression of miR-6515-5p using a mimic inhibited PM10-induced inflammatory responses via inactivation of the ERK pathway, whereas downregulation of miR-6515-5p via an inhibitor significantly increased inflammation in PM10-exposed cells via activation of ERK. Furthermore, we identified colony stimulating factor 3 (CSF3) as a target gene of miR-6515-5p using TargetScanHuman, and confirmed the association between miR-6515-5p and CSF3 using a luciferase reporter assay. Furthermore, we found that mRNA and protein levels of CSF3 were negatively regulated by miR-6515-5p. Inhibition of CSF3 by small interfering RNA significantly reduced the expression and production of inflammatory markers in PM10-exposed cells by inactivating the MAPK/ERK signaling pathway. Therefore, we suggest that miR-6515-5p regulates PM10-induced inflammatory responses by targeting CSF3 via MAPK/ERK signaling in bronchial epithelial cells.

Overexpression of V-ATPase B2 attenuates lung injury/fibrosis by stabilizing lysosomal membrane permeabilization and increasing collagen degradation.

Excessive oxidative stress causes lysosomal membrane permeabilization (LMP), which leads to cell death. Vacuolar ATPase (V-ATPase) is the enzyme responsible for pumping H+ into the cytosol and thus maintaining intracellular pH. Previously, we reported that V-ATPase B2 subunit expression is upregulated in the TiO2-exposed lung epithelium. We investigated the role of the lysosomal V-ATPase B2 subunit in oxidative stress-induced alveolar epithelial cell death and in an experimental lung injury/fibrosis model. Overexpression of V-ATPase B2 increased lysosomal pH and lysosomal activities in the cells. In the presence of H2O2, overexpression of V-ATPase B2 increased survival, and silencing of V-ATPase B2 dramatically increased cell death. Overexpression of V-ATPase B2 diminished H2O2-triggered LMP, as evidenced by a reduction in acridine orange staining and leakage of cathepsin D from the lysosome to the cytoplasm. In addition, V-ATPase B2-overexpressing macrophages exhibited significantly enhanced uptake and degradation of collagen. V-ATPase B2-overexpressing transgenic mice showed significant inhibition of the bleomycin-induced increases in lung inflammation and fibrosis. We conclude that V-ATPase B2 is critical for maintaining lysosomal activities against excessive oxidative stress by stabilizing LMP. Our findings reveal a previously unknown role of this V-ATPase subunit in a lung injury and fibrosis model.

Humidifier Disinfectant Consumption and Humidifier Disinfectant-Associated Lung Injury in South Korea: A Nationwide Population-Based Study.

Humidifier disinfectant (HD) is a household biocidal product used in humidifier water tanks to prevent the growth of microorganisms. In 2011, a series of lung injury cases of unknown causes emerged in children and pregnant women who had used HD in Korea. This study investigated changes in the nationwide number of cases of humidifier disinfectant-associated lung injury (HDLI) in concordance with nationwide HD consumption using data covering the entire Korean population. More than 25 kinds of HD products were sold between 1994 and 2011. The number of diagnosed HDLI, assessed by S27.3 (other injuries of lungs) of the Korea National Health Insurance Service (NHIS) data, sharply increased by 2005, subsequently decreased after 2005, and almost disappeared after 2011 in concordance with the annual number of HD sales. The number of self-reported HDLIs, assessed using data from all suspected HDLI cases registered in the Korea Ministry of Environment, changed with the annual number of HD sales, with a delay pattern, potentially induced by the late awareness of lung injury diseases. The present study suggests that changes in the nationwide annual consumption of HD products were consistent with changes in the annual number of HDLI cases in Korea.

Longitudinal Changes in Clinical Features, Management, and Outcomes of Idiopathic Pulmonary Fibrosis. A Nationwide Cohort Study.

Rationale: In recent decades, diagnosis and treatment recommendations for idiopathic pulmonary fibrosis (IPF) have changed. In Korea, the average life expectancy has increased, unmet healthcare needs have been reduced, and the number of computed tomographic examinations performed has nearly doubled. The Korean Interstitial Lung Disease Study Group conducted a nationwide cohort study for idiopathic interstitial pneumonia, including IPF, and established a registry for IPF.Objectives: Using study data collected by the study group, this study aimed to evaluate longitudinal changes in clinical features, diagnosis, treatment, and mortality and analyze the extent to which changes in medication usage affected IPF-associated mortality.Methods: The study population included newly diagnosed patients with IPF from a cohort study (January 2002 to September 2008, n = 1,839, 2008 group) and prospective registry (January 2012 to August 2018, n = 1,345, 2018 group). Survival curves were estimated using the Kaplan-Meier method, and Cox regression models were used to identify mortality-associated risk factors in each group.Results: The 2018 group was younger, had fewer symptoms, had less honeycombing, underwent more serologic autoimmune marker and pulmonary function tests, had higher oxygen partial pressure and lower carbon dioxide partial pressure values, was less frequently diagnosed by surgical biopsy, and had better survival than the 2008 group. Steroid use and conservative care declined, whereas N-acetylcysteine use increased in this group. Antifibrotic agents were used in only the 2018 group. In the 2008 group, N-acetylcysteine was associated with lower mortality, whereas conservative care was associated with higher mortality. In the 2018 group, the use of antifibrotic agents was associated with lower mortality, and steroid use was associated with higher mortality. The survival rates in the 2008 and 2018 non-antifibrotic agent subgroups were similar.Conclusions: This study analyzed national IPF cohort data spanning 17 years. In clinical practice, the IPF diagnosis was made earlier, steroid and immunosuppressive agent use was reduced, and antifibrotic agents were administered. The survival of patients with IPF has improved over the decades, and antifibrotic use was consistently associated with improved survival.Clinical trial registered with clinicaltrials.gov (NCT04160715).

Anti­inflammatory activity of 3,5,6,7,3',4'­hexamethoxyflavone via repression of the NF­κB and MAPK signaling pathways in LPS­stimulated RAW264.7 cells.

Citrus peel has been used as a Traditional medicine in Asia to treat coughs, asthma and bronchial disorders. Therefore, the anti­inflammatory effects of 3,5,6,7,3',4'­hexamethoxyflavone (quercetogetin, QUE) isolated from Citrus unshiu peel were investigated in lipopolysaccharide (LPS)­induced RAW 264.7 macrophage cells. The results showed that QUE repressed the production of prostaglandin E2 and nitric oxide by suppressing LPS­induced expression of cyclooxygenase­2 and inducible nitric oxide synthase. It also suppressed the production of interleukin (IL)­6, IL­1ß, and tumor necrosis factor­α cytokines, and decreased the nuclear translocation of NF­κB by interrupting the phosphorylation of NF­κB inhibitor α in macrophage cells. Based on the finding that QUE inhibited the phosphorylation of ERK protein expression in LPS­induced RAW264.7 cells, it was confirmed that inhibition of inflammatory responses by QUE was mediated via the ERK pathway. Therefore, this study suggests that QUE has strong anti­inflammatory effects, making it a promising compound for use as a therapeutic agent in treating inflammatory lung diseases, such as emphysema.

Effects of antioxidants on oxidative stress and inflammatory responses of human bronchial epithelial cells exposed to particulate matter and cigarette smoke extract.

Particulate matter (PM) is a type of air pollutant that induces adverse health effects, including acute exacerbation of chronic obstructive pulmonary disease (COPD). However, the effects of co-exposure to PM and cigarette smoke extract (CSE) on bronchial epithelial cells remain unknown. This study investigated the cytotoxic and pro-inflammatory effects of combined exposure to PM and CSE on bronchial epithelial cells, and assessed the potential of antioxidants to inhibit CSE/PM-induced oxidative stress and inflammation. Exposure of epithelial cells to PM or CSE induced cytotoxicity, inflammation, and oxidative stress, all of which were dramatically increased when cells were exposed to the combination of CSE and PM. Importantly, the adverse effects of CSE/PM exposure were suppressed when cells were treated with sulforaphane (SFN) or sulforaphane N-acetylcysteine (SFNAC). Furthermore, SFN and SFNAC suppressed the CSE/PM-induced pro-inflammatory cytokine production and expression of inflammatory genes. Combined PM and CSE exposure further activated the MAPK and Nrf2 signaling pathways. SFN and SFNAC attenuated CSE/PM-induced epithelial toxicity through the ERK/JNK signaling pathway-dependent inhibition of inflammation. Moreover, SFN and SFNAC suppressed ROS generation by activating antioxidant enzymes and Nrf2 signaling. Therefore, SFN and SFNAC could be a promising approach to prevent or mitigate the exacerbation of pulmonary diseases caused by PM and other air pollutants.

Particulate-Matter Related Respiratory Diseases.

Particulate matter (PM) is suspended dust that has a diameter of <10 µm and can be inhaled by humans and deposited in the lungs, particularly the alveoli. Recent studies have shown that PM has an adverse effect on respiratory diseases. The aim of this article is to review respiratory diseases associated with PM. According to existing studies, PM is associated with chronic obstructive pulmonary disease, bronchial asthma, and several other respiratory diseases and increases the mortality rates of these diseases. Moreover, increased exposure in the high concentration of atmospheric PM is associated with the development of lung cancer. The most simple and common way to protect an individual from airborne PM is to wear a face mask that filters out PM. In areas of high concentration PM, it is recommended to wear a face mask to minimize the exposure to PM. However, the use of N95 or KF94 masks can interfere with respiration in patients with chronic respiratory diseases who exhibit low pulmonary function, leading to an increased risk of respiratory failure. Conclusionally, reduction of the total amount of PM is considered to be important factor and strengthening the national warning notification system to vulnerable patients and proper early management of exacerbated patients will be needed in the future.

Exogenous 8-hydroxydeoxyguanosine ameliorates liver fibrosis through the inhibition of Rac1-NADPH oxidase signaling.

BACKGROUND AND AIM: Exogenous 8-hydroxydeoxyguanosine (8-OHdG) was suggested as an inhibitor of Rac1 and NADPH oxidase (NOX). The aim of this study was to evaluate the effects of the exogenous 8-OHdG on hepatic fibrogenesis in vitro and in vivo model of liver fibrosis. METHODS: Adult Sprague-Dawley rats were allocated to sham-operated rats (n = 7), rats that underwent bile duct ligation (BDL) (n = 6), and BDL rats treated with 8-OHdG (60 mg/kg/day by gavage, n = 6). All rats were sacrificed on day 21. Double immunofluorescence staining between either NOX1 or NOX2 and α-smooth muscle actin (SMA) in liver was performed. Hepatic fibrotic contents were assessed by hydroxyproline assay and quantified by Sirius red staining. In vitro, hepatic stellate cell (HSC) line LX-2 and HHSteC cells were stimulated by angiotensin II (10 µM). The reactive oxygen species (ROS) production was measured by confocal microscopy. The expressions of NOX1, NOX2, α-SMA, transforming growth factor (TGF)-ß1, and collagen Iα were analyzed by quantitative real-time polymerase chain reaction or immunoblotting. RESULTS: The 8-OHdG treatment in BDL rats reduced the NOX1 and NOX2 protein expression, which overlapped with α-SMA compared with BDL rats. The 8-OHdG treatment in BDL rats significantly decreased the mRNA expression of NOX1, NOX2, α-SMA, TGF-ß1, and collagen Iα, and fibrotic contents. Increases of ROS production, Rac1 activation, NOX1, NOX2, and fibronectin expression induced by angiotensin II in HSCs were attenuated by 8-OHdG. CONCLUSIONS: Rac1 activation and NOX-derived ROS are implicated to liver fibrosis. The 8-OHdG ameliorates liver fibrosis through the inhibition of Rac1 activation and NOX-derived ROS.

Coix lacryma-jobi var. ma-yuen Stapf sprout extract induces cell cycle arrest and apoptosis in human cervical carcinoma cells.

BACKGROUND: Cervical cancer is the second-leading cause of cancer-related mortality in females. Coix lacryma-jobi L. var. ma-yuen (Rom.Caill.) Stapf ex Hook. f. is the most widely recognized medicinal herb for its remedial effects against inflammation, endocrine system dysfunctions, warts, chapped skin, rheumatism, and neuralgia and is also a nourishing food. METHODS: To investigate the activity of Coix lacryma-jobi sprout extract (CLSE) on cell proliferation in human cervical cancer HeLa cells, we conducted a Cell Counting Kit-8 (CCK-8) assay. Flow-cytometric analysis and western blot analysis were performed to verify the effect of CLSE on the regulation of the cell cycle and apoptosis in HeLa cells. RESULTS: We observed that CLSE significantly inhibited cell proliferation. Furthermore, CLSE dose-dependently promoted cell cycle arrest at the sub-G1/ S phase in HeLa cells, as detected by bromodeoxyuridine (BrdU) staining. The cell-cycle-arrest effects of CLSE in HeLa cells were associated with downregulation of cyclin D1 and cyclin-dependent kinases (CDKs) 2, 4, and 6. Moreover, CLSE induced apoptosis, as determined by flow-cytometric analysis and nuclear DNA fragmentation with Annexin V/propidium iodide (PI) and 4'6'-diamidino-2-phenylindole (DAPI) staining. Induction of apoptosis by CLSE was involved in inhibition of the antiapoptotic protein B-cell lymphoma 2 (Bcl-2) and upregulation of the apoptotic proteins p53, cleaved poly (ADP-ribose) polymerase (PARP), cleaved caspase-3, and cleaved caspase-8. Finally, we observed that CLSE inactivated the phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) pathways. CONCLUSIONS: CLSE causes cell cycle arrest and apoptotic cell death through inactivation of the PI3K/AKT pathway in HeLa cells, suggesting it is a viable therapeutic agent for cervical cancer owing to its anticancer effects.

Effect of exposure to Asian sand dust-Particulate matter on liver Tenascin-C expression in human cancer cell and mouse hepatic tissue.

Asian Sand Dust-Particulate Matter (ASD-PM) aerosol brings large amounts of wind-eroded soil particles containing high concentrations of metallic components caused by industrialization and vehicles. Proinflammatory and cytotoxic cytokines trigger local inflammatory responses and cause a systematically high incidence of cardiovascular and other diseases. Tenascin C (Tn-C) is known to be expressed in damaged tissue or in a developmental stage of tissue. In this study, we examined the expression of Tn-C and Fibronectin in human cancer-cell lines and in liver tissue of mice treated with ASD-PM to investigate the inflammatory and cell-damage effects of ASD-PM. In our in vivo study, mice were intratracheally instilled with saline suspensions of ASD-PM particles. Instillation of these particles was repeated twice a week for 12 weeks and the liver tissues were stained with hematoxylin, eosin, and Masson's trichrome, and we carried out an IF. Tn-C expression in liver tissues was detected by RT-PCR and western blot analysis. In the results, the expression of Tn-C increased in a dose-dependent manner in both RNA and Immunofluorescence assay (IF). In our in vitro study, A549 and Hep3B cell lines were incubated in culture media with Transforming Growth Factor-Beta1(TGF-ß1) and ASD-PM. Immunofluorescence microscopy images showed a two times stronger expression of fluorescence in the ASD-treated group than in that treated with TGF-ß1. They also showed a stronger expression of Tn-C in proportion to the concentration of ASD-PM. We confirmed that ASD-PM when inhaled formally migrated to other organs and induced Tn-C expression. ASD-PM containing metals causes expression of Tn-C in liver tissue in proportion to the concentration of ASD-PM.

Comparison of CPI and GAP models in patients with idiopathic pulmonary fibrosis: a nationwide cohort study.

The clinical course of idiopathic pulmonary fibrosis (IPF) is difficult to predict, partly owing to its heterogeneity. Composite physiologic index (CPI) and gender-age-physiology (GAP) models are easy-to-use predictors of IPF progression. This study aimed to compare the predictive values of these two models. From 2003 to 2007, the Korean Interstitial Lung Disease (ILD) Study Group surveyed ILD patients using the 2002 ATS/ERS criteria. A total of 832 patients with IPF were enrolled in this study. CPI was calculated as follows: 91.0 - (0.65 × %DLCO) - [0.53 × %FVC + [0.34 × %FEV1. GAP stage was calculated based on gender (0-1 points), age (0-2 points), and two physiologic lung function parameters (0-5 points). The two models had similar significant predictive values for patients with IPF (p < 0.001). The area under the curve (AUC) was higher for CPI than GAP for prediction of 1-, 2-, and 3-year mortality in this study. The AUC was higher for surgically diagnosed IPF patients than for clinically diagnosed patients. However, neither CPI nor GAP yielded good predictions of outcomes; the AUC was approximately 0.61~0.65. Although both CPI and GAP stage are significantly useful predictors for IPF, they have limited capability to accurately predict outcomes.

The Phosphodiesterase 4 Inhibitor Roflumilast Protects against Cigarette Smoke Extract-Induced Mitophagy-Dependent Cell Death in Epithelial Cells.

BACKGROUND: Recent studies show that mitophagy, the autophagy-dependent turnover of mitochondria, mediates pulmonary epithelial cell death in response to cigarette smoke extract (CSE) exposure and contributes to the development of emphysema in vivo during chronic cigarette smoke (CS) exposure, although the underlying mechanisms remain unclear. METHODS: In this study, we investigated the role of mitophagy in the regulation of CSE-exposed lung bronchial epithelial cell (Beas-2B) death. We also investigated the role of a phosphodiesterase 4 inhibitor, roflumilast, in CSE-induced mitophagy-dependent cell death. RESULTS: Our results demonstrated that CSE induces mitophagy in Beas-2B cells through mitochondrial dysfunction and increased the expression levels of the mitophagy regulator protein, PTEN-induced putative kinase-1 (PINK1), and the mitochondrial fission protein, dynamin-1-like protein (DRP1). CSE-induced epithelial cell death was significantly increased in Beas-2B cells exposed to CSE but was decreased by small interfering RNA-dependent knockdown of DRP1. Treatment with roflumilast in Beas-2B cells inhibited CSE-induced mitochondrial dysfunction and mitophagy by inhibiting the expression of phospho-DRP1 and -PINK1. Roflumilast protected against cell death and increased cell viability, as determined by the lactate dehydrogenase release test and the MTT assay, respectively, in Beas-2B cells exposed to CSE. CONCLUSION: These findings suggest that roflumilast plays a protective role in CS-induced mitophagy-dependent cell death.

Quercetogetin protects against cigarette smoke extract-induced apoptosis in epithelial cells by inhibiting mitophagy.

Recent studies demonstrate that the autophagy-dependent turnover of mitochondria (mitophagy) mediates pulmonary epithelial cell death in response to cigarette smoke extract (CSE) exposure, and contributes to emphysema development in vivo during chronic cigarette smoke (CS)-exposure, although the underlying mechanisms remain unclear. Here, we investigated the role of mitophagy in regulating apoptosis in CSE-exposed human lung bronchial epithelial cells. Furthermore, we investigated the potential of the polymethoxylated flavone antioxidant quercetogetin (QUE) to inhibit CSE-induced mitophagy-dependent apoptosis. Our results demonstrate that CSE induces mitophagy in epithelial cells via mitochondrial dysfunction, and causes increased expression levels of the mitophagy-regulator protein PTEN-induced putative kinase-1 (PINK1) and the mitochondrial fission protein dynamin-1-like protein (DRP-1). CSE induced epithelial cell death and increased the expression of the apoptosis-related proteins cleaved caspase-3, -8 and -9. Caspase-3 activity was significantly increased in Beas-2B cells exposed to CSE, and decreased by siRNA-dependent knockdown of DRP-1. Treatment of epithelial cells with QUE inhibited CSE-induced mitochondrial dysfunction and mitophagy by inhibiting phospho (p)-DRP-1 and PINK1 expression. QUE suppressed mitophagy-dependent apoptosis by inhibiting the expression of cleaved caspase-3, -8 and -9 and downregulating caspase activity in human bronchial epithelial cells. These findings suggest that QUE may serve as a potential therapeutic in CS-induced pulmonary diseases.

Effect of Rifaximin on Hepatic Fibrosis in Bile Duct-ligated Rat Model.

BACKGROUND/AIMS: The translocation of bacteria and their lipopolysaccharides from the gut can promote fibrosis in cirrhotic patients. The aim of this study was to investigate the effects of rifaximin on hepatic fibrosis in a bile duct-ligated rat model. METHODS: The bile duct ligation (BDL) was carried out for eight days (acute injury model: sham-operated rats [G1], BDL rats [G2], and BDL rats treated with rifaximin [G3]) or 22 days (chronic injury model: sham-operated rats [G4], BDL rats [G5], and BDL rats treated with rifaximin [G6]). Rifaximin (50 mg/kg/day) was administered daily via gavage after BDL. Liver function, serum tumor necrosis factor-alpha (TNF-α), and hepatic hydroxyproline levels were measured. Moreover, a histological analysis of fibrosis contents was performed using sirius red stain. RESULTS: In the acute injury model, the liver function and TNF-α level were not improved after the rifaximin treatment. The hydroxyproline levels (µg/g liver tissue) in G1, G2, and G3 were 236.4±103.1, 444.8±114.4, and 312.5±131.6, respectively; and fibrosis contents (%) were 0.22±0.04, 1.64±0.53, and 1.66±0.44, respectively. The rifaximin treatment did not ameliorate acute BDL-induced fibrosis. In the chronic injury model, the hydroxyproline levels in G4, G5, and G6 were 311.5±72.9, 1,110.3±357.9, and 944.3±209.3, respectively; and fibrosis contents (%) were 0.19±0.03, 5.04±0.18, and 4.42±0.68, respectively (G5 vs. G6, p=0.059). The rifaximin treatment marginally ameliorated chronic BDL-induced fibrosis. CONCLUSIONS: Rifaximin did not reduce inflammation and fibrosis in bile duct-ligated rat model.

Clinical significance of cigarette smoking and dust exposure in pulmonary alveolar proteinosis: a Korean national survey.

BACKGROUND: This study aimed to investigate clinical characteristics of Korean PAP patients and to examine the potential risk factors of PAP. METHODS: We retrospectively reviewed medical records of 78 Korean PAP patients diagnosed between 1993 and 2014. Patients were classified into two groups according to the presence/absence of treatment (lavage). Clinical and laboratory features were compared between the two groups. RESULTS: Of the total 78 PAP patients, 60% were male and median age at diagnosis was 47.5 years. Fifty three percent were ever smokers (median 22 pack-years) and 48% had a history of dust exposure (metal 26.5%, stone or sand 20.6%, chemical or paint 17.7%, farming dust 14.7%, diesel 14.7%, textile 2.9%, and wood 2.9%). A history of cigarette smoking or dust exposure was present in 70.5% of the total PAP patients, with 23% having both of them. Patients who underwent lavage (n = 38) presented symptoms more frequently (38/38 [100%] vs. 24/40 [60%], P < 0.001) and had significantly lower PaO2 and DLCO with higher D(A-a)O2 at the onset of disease than those without lavage (n = 40) (P = 0.006, P < 0.001, and P = 0.036, respectively). Correspondingly, the distribution of disease severity score (DSS) differed significantly between the two groups (P = 0.001). Based on these, when the total patients were categorized according to DSS (low DSS [DSS 1-2] vs. high DSS [DSS 3-5]), smoking status differed significantly between the two groups with the proportion of current smokers significantly higher in the high DSS group (11/22 [50%] vs. 7/39 [17.9%], P = 0.008). Furthermore, current smokers had meaningfully higher DSS and serum CEA levels than non-current smokers (P = 0.011 and P = 0.031), whereas no difference was found between smokers and non-smokers. Regarding type of exposed dust, farming dust was significantly associated with more severe form of PAP (P = 0.004). CONCLUSION: A considerable proportion of PAP patients had a history of cigarette smoking and/or dust exposure, suggestive of their possible roles in the development of PAP. Active cigarette smoking at the onset of PAP is associated with the severity of PAP.

Coix lacryma-jobi var. ma-yuen Stapf sprout extract has anti-metastatic activity in colon cancer cells in vitro.

BACKGROUND: Coix lacryma-jobi var. ma-yuen (Rom.Caill.) Stapf has been used in China as an herbal medicine. Many studies of this plant have reported anti-proliferative and apoptotic activities on human cancer cell lines. Therefore, this study of the anti-metastatic effect of Coix lacryma-jobi var. ma-yuen Stapf sprout extract (CLSE) in colorectal cancer cells may provide a scientific basis for exploring anti-cancer effects of edible crops. METHODS: To evaluate the effect of CLSE on cell proliferation and signaling, we performed a Cell Counting Kit-8 (CCK-8) assay in HCT116 cells and used western blot analysis. Furthermore, scratch-wound healing, transwell migration, matrigel invasion, and adhesion assays were conducted to elucidate the anti-metastatic effects of CLSE under hypoxic conditions in colon cancer cells. RESULTS: First, CLSE decreased deferoxamine (DFO)-induced migration of colon cancer cells by 87%, and blocked colon cancer cell migration by 80% compared with hypoxia control cells. Second, CLSE treatment resulted in a 54% reduction in hypoxia-induced invasiveness of colon cancer cells, and 50% inhibition of adhesive potency through inactivation of the extracellular signal-regulated kinase (ERK) 1/2 and protein kinase b (AKT) pathways. Third, conditioned medium collected from CLSE-treated HCT116 cells suppressed tube formation of human umbilical vein endothelial cells (HUVECs) by 91%. CONCLUSIONS: CLSE inhibited migration, invasion, and adhesion of colon cancer cells and tube formation by HUVECs via repression of the ERK1/2 and AKT pathways under hypoxic conditions. Therefore, CLSE may be used to treat patients with colon cancer.

A Retrospective Study Investigating Risks of Acute Respiratory Distress Syndrome and Mortality Following Human Metapneumovirus Infection in Hospitalized Adults.

BACKGROUND: Human metapneumovirus (hMPV) is a relatively recently identified respiratory virus that induces respiratory symptoms similar to those of respiratory syncytial virus infection in children. The characteristics of hMPV-infected adults are unclear because few cases have been reported. METHODS: We conducted a retrospective review of hospitalized adult patients with a positive multiplex real-time polymerase chain reaction assay result from 2012 to 2016 at a single tertiary referral hospital in South Korea. We analyzed clinical characteristics of the enrolled patients and divided patients into an acute respiratory distress syndrome (ARDS) group and a non-ARDS group. RESULTS: In total, 110 adults were reviewed in this study. Their mean age was 61.4 years, and the majority (n = 105, 95.5%) had comorbidities or were immunocompromised. Most of the patients had pneumonia on chest X-ray (n = 88, 93.6%), 22 (20.0%) had ARDS, and 12 (10.9%) expired during hospitalization. The mortality rate for patients with ARDS was higher than that of the other patients (36.4% vs. 5.7%, P = 0.001). The risk factor for hMPV-associated ARDS was heart failure (odds ratio, 5.24; P = 0.044) and laboratory values were increased blood urea nitrogen and increased C-reactive protein. The acquisition site of infection was divided into community vs. nosocomial; 43 patients (39.1%) had a nosocomial infection. The risk factors for nosocomial infection were an immunocompromised state, malignancy and immunosuppressive treatment. CONCLUSIONS: These data suggest that hMPV is one of the important respiratory pathogens important respiratory pathogen that causes pneumonia/ARDS in elderly, immunocompromised individuals and that it may be transmitted via the nosocomial route.