Impaired TNFα-induced VEGF Expression in Human Airway Smooth Muscle Cells from Smokers with COPD: Role of MAPkinases and Histone Acetylation—Effect of Dexamethasone

The cytokine and potent angiogenic factor vascular endothelial growth factor (VEGF) plays an important role in airway remodelling in various airway diseases such as idiopathic pulmonary fibrosis, pulmonary hypertension, lung cancer, asthma and chronic obstructive pulmonary disease (COPD). The effect of cigarette-smoking on VEGF expression, the modulatory role of extracellular signal-regulated kinase (ERK)-1,-2, p38mitogen-activated protein kinase (MAPK), histone acetylation and the anti-inflammatory effect of dexamethasone on TNFα-induced VEGF expression were examined in human airway smooth muscle cells (HASMC) of five non-smokers, 17 smokers without airflow limitation and 15 smokers with COPD. TNFα increased VEGF expression 5.4-fold and 4.0-fold in HASMC from non-smokers and smokers without airflow limitation, respectively, but only 2.5-fold in HASMC from smokers with COPD compared with non-stimulated HASMC. VEGF production was dependent on phosphorylation of ERK-1,-2 and p38^MAPK, as was shown by examining the effects of PD 098059 (10 μM), an inhibitor of the upstream activator of MAPKkinase (MKK)-1, and SB 203580 (10 μM), an inhibitor of p38^MAPK; there were no differences between non-smokers, smokers without airflow limitation and smokers with COPD in this respect. Dexamethasone (DEX; 10⁻¹²–10⁻⁴ M) reduced TNFα-induced phosphorylation of ERK-1/-2 and prevented TNFα-induced VEGF generation without differences between non-smokers, smokers with and without COPD. There was an additional inhibitory effect of DEX (10⁻¹² M) on VEGF-release when PD 098059 was added. The basal and TNFα-induced acetylation status of the VEGF-promoter (chromatin immunoprecipitation [ChIP] assay) was increased in HASMC from smokers with COPD compared with smokers without airflow limitation and non-smokers. In comparison to non-stimulated HASMC, TNFα decreased the acetylation status of the VEGF-promoter by ∼46% and ∼43% in HASMC from non-smokers and smokers without COPD compared with ∼68% in HASMC from smokers with COPD. The data suggest that HASMC express VEGF in response to TNFα and that this may be reduced in HASMC of smokers with COPD in a smoking-independent manner. VEGF expression is directly modulated by phosphorylation of ERK-1,-2 and p38^MAPK and by histone acetylation and the acetylation status of the VEGF gene is increased in HASMC of smokers with COPD in a smoking-independent manner. TNFα reduced the acetylation status of the VEGF promoter in HASMC.     

Application of the entomogenous fungus,Metarhizium anisopliae,for leafroller (Cnaphalocrocis medinalis) control and its effect on rice phyllosphere microbial diversity

Applied Microbiology and Biotechnology - Microbial pesticides form critical components of integrated pest management (IPM) practices. Little, however, is known regarding the impacts of these...     

Untargeted GC–MS investigation of serum metabolomics of coronary artery disease patients

Recent advances in metabolomics provide tools to investigate human metabolome in order to establish new parameters to study different approaches towards diagnostics, diseases and their treatment. The present study focused on the untargeted identification of metabolites in serum of patients with coronary artery disease who were under treatment at the time of sample collection. AUCs (Area Under the Curves) from different peaks were considered for the analysis and comparison purposes. The metabolome was studied using GC–MS (Gas Chromatography Mass Spectrometry) and the metabolites were identified with NIST (The National Institute of Standards and Technology) and Wiley library matches. A total of 17 metabolites were identified and focused on to compare with the metabolome of healthy individuals. T test analysis found significant differences in alanine, malonic acid, ribitol, D-glucose, mannose (P < 0.001), acetohydroxamic acid, N-carboxyglycine, and aminobutyrate (P < 0.05). Principal Component Analysis of serum metabolites data found three components out of 17 metabolites; RC1 (Acetohydroxamic acid, alanine, D-glucose, malonic acid, mannose, N-carboxy glycine and ribitol), RC2 (Heptadecanoic acid, hexadecanoic acid, octadecanoic acid and Trans-9-octadecanoic acid), RC3 (Aminobutyrate, D-sorbit, gamma lactone, valine, benzene propanoic acid and lactic acid). No correlation was found among the components.     

The MAP kinase Bbslt2 controls growth, conidiation, cell wall integrity, and virulence in the insect pathogenic fungus Beauveria bassiana

Entomopathogenic fungi, such as Beauveria bassiana, are key environmental pathogens of insects that have been exploited for biological control of insect pests. Mitogen-activated protein (MAP) kinases play crucial roles in regulating fungal development, growth, and pathogenicity, mediating responses to the environment. Bbslt2, encoding for an Slt2 family MAPK, was isolated and characterized from B. bassiana. Gene disruption of Bbslt2 affected growth, caused a significant reduction in conidial production and viability, and increased sensitivity to Congo Red and fungal cell wall degrading enzymes. ΔBbslt2 mutants were altered in cell wall structure and composition, which included temperature dependent chitin accumulation, reductions in conidial and hyphal hydrophobicity, and alterations in cell surface carbohydrate epitopes. The ΔBbslt2 strain also showed hypersensitivity to heat shock and altered trehalose accumulation, which could only be partially attributed to changes in the expression of trehalase (ntl1). Insect bioassays revealed decreased virulence in the ΔBbslt2 strain using both topical and intrahemoceol injection assays. These results indicate that Bbslt2 plays an important role in conidiation, viability, cell wall integrity and virulence in B. bassiana. Our findings are discussed within the context of the two previous MAP kinases characterized from B. bassiana.     

Have biopesticides come of age?

Biopesticides based on living microbes and their bioactive compounds have been researched and promoted as replacements for synthetic pesticides for many years. However, lack of efficacy, inconsistent field performance and high cost have generally relegated them to niche products. Recently, technological advances and major changes in the external environment have positively altered the outlook for biopesticides. Significant increases in market penetration have been made, but biopesticides still only make up a small percentage of pest control products. Progress in the areas of activity spectra, delivery options, persistence of effect and implementation have contributed to the increasing use of biopesticides, but technologies that are truly transformational and result in significant uptake are still lacking.