OBJECTIVE: To investigate the mechanism of activator protein-1 (AP-1) on cigarette smoke-induced airway mucous hypersecretion and to explore the possible signal transduction pathway that activates AP-1. METHODS: The airway epithelial cell line (BEAS-2B) was cultured in vivo and treated with cigarette smoke extract (CSE). The DNA binding activity of AP-1 was blocked by the transfection of c-Jun dominant negative mutant TAM67 into the cells. SP600125 and PD98059 were used to block the activation of c-Jun terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) respectively. MUC5AC protein was detected by enzyme-linked immunosorbent assay, MUC5AC mRNA level was analyzed by RT-PCR, while the protein contents of p-JNK, p-ERK and p-P38 were detected by Western blot, and the DNA binding activity of AP-1 was determined by electrophoretic mobility shift assay. RESULTS: The MUC5AC protein production and mRNA expression in the CSE group were significantly higher than those in the control group, and the DNA binding activity of AP-1 was also higher than that in the control group (P<0.01). The protein contents of p-ERK and p-JNK in the CSE group were higher than those in the control group (P<0.01), but the p-P38 level was not significantly different from that in the control group (P>0.05). After the transfection of TAM67 into the cells, the expression levels of MUC5AC protein and mRNA and the binding activity of AP-1 decreased significantly (P<0.01). The DNA binding activity of AP-1 and the expression levels of MUC5AC protein and mRNA were lower in the SP600125 group and in the PD98059 group than those in the CSE group (P<0.05). CONCLUSION After being activated by JNK and ERK which are phosphorylated by cigarette smoke, AP-1 binds to its DNA binding elements on the promoter of MUC5AC gene and up-regulates the MUC5AC expression at the transcriptional level.
Bronchi ; cytology ; Cells, Cultured ; Epithelial Cells ; cytology ; metabolism ; Humans ; Mucin 5AC ; genetics ; metabolism ; Smoke ; adverse effects ; Smoking ; adverse effects ; Tobacco ; chemistry ; Transcription Factor AP-1 ; pharmacology

To analyze and compare the protective effects of active components in different ethyl acetate extracts (EAEEPs) from Eclipta prostrate, in order to study the comparison of materials bases protecting normal human bronchial epithelial (NHBE) cells. The MTT assay was taken to compare the protective effect of different EAEEPs on cigarette smoke extracts (CSE) -induced NHBE cells. The ultra-performance liquid chromatography (UPLC) was applied to analyze the content of phenolic acid, coumaric grass ether and flavonoid in EAEEPs. According to the results, all of the eight EAEEPs (0-200 mg x L(-1)) showed certain protective effect on NHBE cells, with statistical difference. Specifically, the total mass of EAEEP VII (89.15 mg x L(-1)) and EAEEP VIII (57.44 mg x L(-1)), which showed the strongest activity, was not the highest, while EAEEP III (132.25 mg x L(-1)) displayed the highest total mass. In the combination with the "component structure" theory, the analysis showed a significant difference in the mass structure among phenolic acid, coumaric grass ether and flavonoid in EAEEP VIII and EAEEP VIII, which were 1.0: 1. 0: 0.5 and 1.0: 1.9: 0.8, respectively. The results suggested a specific optimal "component structure" relationship may exist in EAEEP, which could provide reference for the material base study and quality control.
Bronchi ; cytology ; drug effects ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; pharmacology ; Eclipta ; chemistry ; Epithelial Cells ; cytology ; drug effects ; Humans ; Protective Agents ; chemistry ; isolation & purification ; pharmacology ; Tobacco Smoke Pollution ; adverse effects

OBJECTIVETo investigate the protective effect and mechanism of Ecliptae Herba extract on cigarette smoke extract-induced cytotoxicity.

METHODThe effect of Ecliptae Herba extract on CSE-induced NHBE cell proliferation was detected by MTT assay. GSH content was determined by DTNB colorimetry. GST activity was measured by CDNB colorimetric assay. NQO1 activity was detected by NADPH and DCIP. The protein expression was determined by Western blot assay.

RESULTEcliptae Herba extract reduced CSE's inhibitory effect on NHBE cells, recover the decrease in intracellular GSH caused by CSE and reduce the CSE-induced activity of GST and NQO1 and NQO1 protein expression.

CONCLUSIONEcliptae Herba extract can reduce CSE-induced injury on NHBE cells, which may be related to phase II detoxification enzymes.

Cell Line ; Cell Proliferation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Eclipta ; chemistry ; Gene Expression ; drug effects ; Humans ; NAD(P)H Dehydrogenase (Quinone) ; genetics ; metabolism ; Protective Agents ; pharmacology ; Smoke ; analysis ; Smoking ; adverse effects ; Tobacco ; chemistry

To investigate the effects of cigarette smoking in different manners on acute lung injury in rats.The commercially available cigarettes with tar of 1,5, 11 mg were smoked in Canada depth smoking (health canada method, HCM) manner, and those with tar of 11 mg were also smoked in international standard (ISO) smoking manner. Rats were fixed and exposed to mainstream in a manner of nose-mouth exposure. After 28 days, the bronchoalveolar lavage fluids from left lung were collected for counting and classification of inflammatory cells and determination of pro-inflammatory cytokines IL-1β and TNF-α. The right lungs were subjected to histological examination and determination of myeloperoxidase (MPO) and superoxide dismutase (SOD) activities and glutathione, reactive oxygen species (ROS) and malondialdehyde (MDA) levels.In both HCM and ISO manners, the degree of lung injury was closely related to the tar content of cigarettes, and significant decrease in the body weight of rats was observed after smoking for one week. In a HCM manner, smoking with cigarette of 11 mg tar resulted in robust infiltration of macrophages, lymphocytes and neutrophils into lungs, significant increase in IL-1β and TNF-α levels and MPO activities, and significant decrease in GSH levels and SOD activities and increase in ROS and MDA levels (all<0.05). Smoking with cigarette of 5 mg tar led to moderate increase in IL-1β and TNF-α levels, and MPO activities (all<0.05), and moderate decrease in GSH levels and SOD activities and increase of ROS and MDA levels (all<0.05). However, smoking with cigarette of 1 mg tar affected neither inflammatory cell infiltration nor IL-1β and TNF-α levels.Cigarette smoking in nose-mouth exposure manner can induce acute lung injury in rats; and the degree of lung injury is closely related to the content of tar and other hazards in cigarettes.
Acute Lung Injury ; etiology ; pathology ; physiopathology ; Animals ; Bronchoalveolar Lavage Fluid ; chemistry ; cytology ; Chemotaxis, Leukocyte ; drug effects ; Glutathione ; analysis ; drug effects ; Interleukin-1beta ; analysis ; drug effects ; Lung ; chemistry ; pathology ; Lymphocytes ; drug effects ; pathology ; Macrophages ; drug effects ; pathology ; Male ; Malondialdehyde ; analysis ; Neutrophil Infiltration ; drug effects ; Neutrophils ; drug effects ; pathology ; Peroxidase ; analysis ; drug effects ; Rats ; Reactive Oxygen Species ; analysis ; Smoking ; adverse effects ; Superoxide Dismutase ; analysis ; drug effects ; Tobacco Products ; adverse effects ; classification ; Tumor Necrosis Factor-alpha ; analysis ; drug effects ; Weight Loss ; drug effects

OBJECTIVETo study the genotoxicity effect of environmental tobacco side-stream smokes (ETSS) on oxidative DNA damage and its molecular mechanism.

METHODSDNA adduct 8-hydroxydeoxyguanosine (8-OHdG) was used as a biomarker of oxidative DNA damage. The level of 8-OHdG in DNA exposed to ETSS was detected by high performance liquid chromatography with electrochemical detection. Organic and inorganic components in ETSS were analyzed by gas chromatography-mass spectrum and atomic absorption spectrum respectively.

RESULTSParticle matters (PMs) and volatile organic compounds (VOCs) in ETSS could directly induce oxidative DNA damage and formation of 8-OHdG. There were 123 and 84 kinds of organic components in PMs and VOCs respectively, and 7 kinds of inorganic components in ETSS. Some components, especially quinones and polyphenols in ETSS, could produce free radicals in vitro by auto-oxidation without any biological activity systems, and with the catalytic reaction of metals, the DNA adduct 8-OHdG was produced.

CONCLUSIONETSS have biological oxidative effect on DNA in vitro and in vivo, and expressed direct genotoxicity. 8-OHdG is a valuable biomarker of oxidative DNA damage.

Animals ; Biomarkers ; analysis ; Cattle ; DNA ; drug effects ; metabolism ; DNA Adducts ; analysis ; DNA Damage ; Deoxyguanosine ; analogs & derivatives ; analysis ; Female ; Lung ; chemistry ; metabolism ; Metals, Heavy ; analysis ; Organic Chemicals ; analysis ; Oxidation-Reduction ; Rats ; Tobacco Smoke Pollution ; adverse effects ; analysis

BACKGROUNDIncreased proliferation of airway smooth muscle cells (ASMCs) are observed in asthmatic patients and smoking can accelerate proliferation of ASMCs in asthma. To elucidate the molecular mechanisms leading to these changes, we studied in vitro the effect of cigarette smoke extract (CSE) on the proliferation of ASMCs and the expression of cyclin D1, an important regulatory protein implicated in cell cycle.

METHODSASMCs cultured from 8 asthmatic Brown Norway rats were studied. Cells between passage 3 and 6 were used in the study and were divided into control group, pcDNA3.1 group, pcDNA3.1-antisense cyclin D1 (ascyclin D1) group, CSE group, CSE + pcDNA3.1 group and CSE + pcDNA3.1-ascyclin D1 group based on the conditions for intervention. The proliferation of ASMCs was examined with cell cycle analysis, MTT colorimetric assay and proliferating cell nuclear antigen (PCNA) immunocytochemical staining. The expression of cyclin D1 was detected by reverse transcriptase-PCR (RT-PCR) and Western blotting.

RESULTS(1) The percentage of S + G2M phase, absorbance value at 490 nm wavelength (A(490)) and the expression rate of PCNA protein in CSE group were (31.22 +/- 1.17)%, 0.782 +/- 0.221, (90.2 +/- 7.0)% respectively, which were significantly increased compared with those of control group ((18.36 +/- 1.02)%, 0.521 +/- 0.109, and (54.1 +/- 3.5)%, respectively) (P < 0.01). After the transfection with antisense cyclin D1 plasmid for 30 hours, the percentage of S + G2M phase, A(490) and the expression rate of PCNA protein in ASMCs were much lower than in untreated cells (P < 0.01). (2) The ratios of A(490) of cyclin D1 mRNA in CSE group was 0.288 +/- 0.034, which was significantly increased compared with that of control group (0.158 +/- 0.006) (P < 0.01). After the transfection with antisense cyclin D1 plasmid for 30 hours, the ratios of A(490) of cyclin D1 mRNA in ASMCs was much lower than in untreated cells (P < 0.01). (3) The ratios of A(490) of cyclin D1 protein expression in CSE group was 0.375 +/- 0.008, which was significantly increased compared with that of control group (0.268 +/- 0.004) (P < 0.01). After the transfection with antisense cyclin D1 plasmid for 30 hours, the ratios of A(490) of cyclin D1 protein expression in ASMCs was much lower than in untreated cells (P < 0.01).

CONCLUSIONCSE may increase the proliferation of ASMCs in asthmatic rats via regulating cyclin D1 expression.

Animals ; Asthma ; metabolism ; Blotting, Western ; Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cyclin D1 ; genetics ; metabolism ; Disease Models, Animal ; Female ; Flow Cytometry ; Immunohistochemistry ; Microscopy, Phase-Contrast ; Myocytes, Smooth Muscle ; cytology ; drug effects ; metabolism ; Plant Extracts ; toxicity ; Rats ; Respiratory System ; cytology ; drug effects ; Reverse Transcriptase Polymerase Chain Reaction ; Smoking ; adverse effects ; Tobacco ; chemistry

Matrix metalloproteinase-9 (MMP-9) may play an important role in emphysematous change in chronic obstructive pulmonary disease (COPD), one of the leading causes of mortality and morbidity worldwide. We previously reported that simvastatin, an inhibitor of HMG-CoA reductase, attenuates emphysematous change and MMP-9 induction in the lungs of rats exposed to cigarette smoke. However, it remained uncertain how cigarette smoke induced MMP-9 and how simvastatin inhibited cigarette smoke-induced MMP-9 expression in alveolar macrophages (AMs), a major source of MMP-9 in the lungs of COPD patients. Presently, we examined the related signaling for MMP-9 induction and the inhibitory mechanism of simvastatin on MMP-9 induction in AMs exposed to cigarette smoke extract (CSE). In isolated rat AMs, CSE induced MMP-9 expression and phosphorylation of ERK and Akt. A chemical inhibitor of MEK1/2 or PI3K reduced phosphorylation of ERK or Akt, respectively, and also inhibited CSE-mediated MMP-9 induction. Simvastatin reduced CSE-mediated MMP-9 induction, and simvastatin-mediated inhibition was reversed by farnesyl pyrophosphate (FPP) or geranylgeranyl pyrophosphate (GGPP). Similar to simvastatin, inhibition of FPP transferase or GGPP transferase suppressed CSE-mediated MMP-9 induction. Simvastatin attenuated CSE-mediated activation of RAS and phosphorylation of ERK, Akt, p65, IkappaB, and nuclear AP-1 or NF-kappaB activity. Taken together, these results suggest that simvastatin may inhibit CSE-mediated MMP-9 induction, primarily by blocking prenylation of RAS in the signaling pathways, in which Raf-MEK-ERK, PI3K/Akt, AP-1, and IkappaB-NF-kappaB are involved.
1-Phosphatidylinositol 3-Kinase/metabolism ; Alkyl and Aryl Transferases/metabolism ; Animals ; Anticholesteremic Agents/pharmacology ; Cells, Cultured ; Enzyme Inhibitors/metabolism/pharmacology ; Extracellular Signal-Regulated MAP Kinases/metabolism ; Gene Expression Regulation, Enzymologic/*drug effects ; I-kappa B Kinase/antagonists & inhibitors/metabolism ; Macrophages, Alveolar/cytology/*drug effects/*enzymology ; Matrix Metalloproteinase 9/genetics/*metabolism ; Mitogen-Activated Protein Kinase Kinases/metabolism ; Polyisoprenyl Phosphates/metabolism ; Proto-Oncogene Proteins c-akt/metabolism ; Rats ; Sesquiterpenes/metabolism ; Signal Transduction/physiology ; Simvastatin/*pharmacology ; Smoke/*adverse effects ; *Tobacco/adverse effects/chemistry

BACKGROUNDIt is widely accepted that tumor necrosis factor-α (TNF-α) plays an important role in the pathogenesis of emphysema. This study aimed at investigating the protective effects of anti-TNF-α antibody, infliximab, in the development of emphysema induced by passive smoking in rats.

METHODSThirty-nine rats were randomly divided into a normal control group (group 1), an emphysema group (group 2), and an infliximab-intervention group (group 3). Rat models of emphysema were established by exposure to cigarette smoking daily for 74 days. After 1 month, the infliximab intervention group was treated with infliximab via subcutaneous injection. The levels of TNF-α, IL-8 and vascular endothelial growth factor (VEGF) in bronchoalveolar lavage fluid (BALF) were measured with enzyme linked immunosorbent assay (ELISA). The number and classification of cells in the BALF were measured. Lung tissue sections stained by hematoxylin and eosin (HE) were observed, and mean linear intercept (MLI) and mean alveolar numbers (MAN) were measured. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) methods were used to examine the percentage of positive cells and distribution of apoptotic cells.

RESULTSThe levels of TNF-α and IL-8 in BALF were higher in group 2 than in group 1 and group 3. The MLI was greater in group 2 than that in group 1 and group 3 while MAN was decreased. The concentration of VEGF in BALF of group 2 was significantly decreased as compared with group 1. The total cells and neutrophils number was significantly increased in group 2 as compared with group 1 and group 3, so was the percentage of neutrophils. The number of TUNEL positive cells in the alveolar septa was significantly increased in group 2 as compared with group 1 and group 3.

CONCLUSIONInfliximab protects against cigarette smoking-induced emphysema by reducing airway inflammation, attenuating alveolar septa cell apoptosis and improving pathological changes.

Animals ; Antibodies, Monoclonal ; therapeutic use ; Bronchoalveolar Lavage Fluid ; chemistry ; cytology ; Infliximab ; Interleukin-8 ; metabolism ; Male ; Pulmonary Alveoli ; cytology ; drug effects ; Pulmonary Emphysema ; chemically induced ; metabolism ; prevention & control ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tobacco Smoke Pollution ; adverse effects ; Tumor Necrosis Factor-alpha ; metabolism