BACKGROUND/AIMS: Role of autophagy in neutrophil function and the association of autophagy and autophagy related (ATG) gene polymorphisms with asthma susceptibility were suggested. In this study, we investigated the genetic association of ATG5 and ATG7 polymorphisms with asthma risk, severity and neutrophilic airway inflammation. METHODS: We recruited 408 asthma patients and 201 healthy controls. Sputum neutrophil counts were determined by H&E staining. Serum interleukin 8 (IL-8) levels were measured by enzyme-linked immunosorbent assay (ELISA). Genetic polymorphisms of ATG5 (-769T>C, -335G>A, and 8830C>T) and ATG7 (-100A>G and 25108G>C) were genotyped. The functional activities of ATG5 -769T>C and -335G>A variants were investigated by luciferase reporter assays. RESULTS: No associations of ATG5 and ATG7 polymorphisms with asthma susceptibility and severity were found. ATG5 -769T>C and -335G>A were in complete linkage disequilibrium. In the asthma group, GA/AA genotypes at ATG5 -335G>A were associated with higher neutrophil counts in sputum (p < 0.05); CC/TT genotype at ATG5 8830C>T associated with lower FEV1% predicted value (p < 0.05). DNA fragments containing ATG5 -769T and -335G alleles had higher promoter activities compared to those with -769C and -335A in both human airway epithelial cells (A549, p < 0.01) and human mast cell (HMC-1, p < 0.001). GG and CC genotype at ATG7 -100A>G and 25108G>C were significantly associated with high serum levels of IL-8 (p < 0.05 for both variants). CONCLUSIONS: Genetic polymorphisms of ATG5 and ATG7 could contribute to neutrophilic airway inflammation in the pathogenesis of adult asthma.
Adolescent ; Adult ; Asthma/blood/*genetics/immunology/pathology ; Autophagy/*genetics ; Autophagy-Related Protein 5/*genetics ; Autophagy-Related Protein 7/*genetics ; Case-Control Studies ; Cell Line ; Female ; Gene Frequency ; Genes, Reporter ; Genetic Predisposition to Disease ; Haplotypes ; Heterozygote ; Homozygote ; Humans ; Interleukin-8/blood ; Male ; Middle Aged ; Neutrophil Infiltration/*genetics ; Neutrophils/immunology/metabolism/*pathology ; Phenotype ; *Polymorphism, Single Nucleotide ; Promoter Regions, Genetic ; Risk Factors ; Severity of Illness Index ; Transfection ; Young Adult

OBJECTIVETo study the expression of Galectin-9 and Tim-3 in lungs of mice with asthma and the effect of rosiglitazone (PPAR-γ agonist) on their expression.

METHODSFortyfive BALB/c SPF female mice were randomized into control group and asthma groups with and without rosiglitazone intervention. After ovalbumin stimulation and rosiglitazone intervention the pathological changes of the lung tissues were observed. Galectin-9 and Tim-3 mRNA levels in lung tissues were determined using RT-PCR. The levels of IL-4 and IFN-γ in peripheral blood were measured using ELISA.

RESULTSThe expression of Galectin-9 and Tim-3 mRNA of lung tissues in the untreated asthma group increased significantly compared with the control and the rosiglitazone treated groups (P<0.05). A significantly increased blood expression of IL-4 and a significantly decreased blood expression of IFN-γ were found in the untreated asthma group compared with the control and the rosiglitazone-treated groups (P<0.05). The expression of Galectin-9 and Tim-3 mRNA was positively correlated with blood IL-4 level (r=0.792, r=0.794 respectively; P<0.05), but negatively correlated with blood IFN-γ level (r=-0.692, r=-0.757 respectively; P<0.05).

CONCLUSIONSGalectin-9 and Tim-3 mRNA levels in lungs increase in mice with asthma and significantly correlate with the levels of blood Th1/Th2 cytokines. This suggests that Galectin-9 and Tim-3 are closely related to inflammatory process in asthma. Rosiglitazone treatment may decrease the expression of Galectin-9 and Tim-3.

Animals ; Asthma ; drug therapy ; immunology ; pathology ; Female ; Galectins ; genetics ; Hepatitis A Virus Cellular Receptor 2 ; Interferon-gamma ; blood ; Interleukin-4 ; blood ; Lung ; metabolism ; pathology ; Mice ; Mice, Inbred BALB C ; PPAR gamma ; physiology ; RNA, Messenger ; analysis ; Receptors, Virus ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Th1 Cells ; immunology ; Th2 Cells ; immunology ; Thiazolidinediones ; therapeutic use

OBJECTIVETo study the correlation between airway inflammation and osteopontin (OPN) level in the lung tissue, and to study the effect of dexamethasone (DXM) on OPN expression.

METHODSFifty mice were randomly divided into 5 groups: normal control, ovalbumin (OVA)-challenged asthma groups (OVA inhalation for 1 week or 2 weeks) and DXM-treated asthma groups (DXM treatment for 1 week or 2 weeks). The mice were sensitized and challenged with OVA to prepare mouse model of acute asthma. Alterations of airway inflammation were observed by haematoxylin-eosin staining. Serum level of OVA-sIgE was evaluated using ELISA. OPN expression in the lung tissue was located and measured by immunohistochemistry and Western blot respectively. OPN mRNA level in the lung tissue was detected by real-time PCR.

RESULTSThe asthma groups showed more pathological changes in the airway than the normal control and the DXM-treated groups. Compared with the OVA-challenged 1 week group, the pathological alterations increased in the OVA-challenged 2 weeks group. The level of OVA-sIgE in serum increased in the asthma groups compared with the control and the DXM groups (P<0.01). Serum OVA-sIgE sevel increased more significantly in the OVA-challenged 2 weeks group compared with the OVA-challenged 1 week group (P<0.01). OPN protein and mRNA levels were significantly raised in the asthma groups compared with the normal control and the DXM groups (P<0.01), and both levels increased more significantly in the OVA-challenged 2 weeks group compared with the OVA-challenged 1 week group (P<0.01).

CONCLUSIONSThe increased OPN expression in the lung tissue is associated with more severe airway inflammation in asthmatic mice, suggesting that OPN may play an important role in the pathogenesis of asthma. DXM can alleviate airway inflammation possibly by inhibiting OPN production.

Animals ; Asthma ; drug therapy ; metabolism ; pathology ; Dexamethasone ; therapeutic use ; Enzyme-Linked Immunosorbent Assay ; Female ; Immunoglobulin E ; blood ; Lung ; metabolism ; pathology ; Mice ; Mice, Inbred BALB C ; Osteopontin ; analysis ; genetics ; physiology ; Ovalbumin ; immunology

BACKGROUND: Several methods have been reported to induce asthmatic reactions in mice but few studies have compared their efficiency. We evaluated the efficiency of the protocols frequently used in the literature. METHODS: BALB/c mice were sensitized to ovalbumin (OVA) by intraperitoneal injection; 1] Once a week for two weeks using OVA with alum (IPOA-2) or without (IPO-2), and provocation on days 28-30 by 1% OVA inhalation; 2] seven times for two weeks by OVA with alum (IPOA-7) or without (IPO-7) and provocation by 1% OVA inhalation on days 42-44. 3] Sensitization by 1% OVA inhalation for ten days (IHO-10) and provocation by 1% OVA inhalation on days 28-30. After the last challenge, airway hyperresponsiveness was measured with single chamber plethysmography 24 hours later and mice were sacrificed 48 hours later. RESULTS: Airway hyperresponsiveness, BALF eosinophilia, airway inflammation, and OVA-specific IgE and IgG1 production were effectively induced in IPOA-2, IPOA-7, and IPO-7. However, these phenotypes were not induced in IPO-2 (except for increased BALF eosinophils) or IHO-10 (except for an increased OVA-specific IgG1 level). CONCLUSION: The intraperitoneal injections of OVA with alum once a week for two weeks proved to be the most efficient sensitization method of inducing an asthmatic reaction in mice.
Administration, Inhalation ; Animals ; Antibodies, Anti-Idiotypic/blood ; Asthma/diagnosis/*genetics/immunology ; *Bronchial Provocation Tests ; Comparative Study ; Disease Models, Animal ; Female ; Immunoglobulin G/immunology ; Injections, Intraperitoneal ; Lung/pathology ; Mice ; Mice, Inbred BALB C ; Ovalbumin/administration & dosage/*diagnostic use/immunology ; *Phenotype ; Research Support, Non-U.S. Gov't