What is new in the management of childhood asthma?

Transcriptome analysis of peripheral whole blood identifies crucial lncRNAs implicated in childhood asthma

Background

Asthma is a chronic disorder of both adults and children affecting more than 300 million people heath worldwide. Diagnose and treatment for asthma, particularly in childhood asthma have always remained a great challenge because of its complex pathogenesis and multiple triggers, such as allergen, viral infection, tobacco smoke, dust, etc. It is thereby great significant to deeply investigate the transcriptome changes in asthmatic children before and after desensitization treatment, in order that we could identify potential and key mRNAs and lncRNAs which might be considered as useful RNA molecules for observing and supervising desensitization therapy for asthma, which might guide the diagnose and therapy in childhood asthma.

Methods

In the present study, we performed a systematic transcriptome analysis based on the deep RNA sequencing of ten asthmatic children before and after desensitization treatment, including identification of lncRNAs using a stringent filtering pipeline, differential expression analysis and network analysis, etc.

Results

First, a large number of lncRNAs were identified and characterized. Then differential expression analysis revealed 39 mRNAs and 15 lncRNAs significantly differentially expressed which involved in two biological processes and pathways. A co-expressed network analysis figured out a desensitization-treatment-related module which contains 27 mRNAs and 21 lncRNAs using WGCNA R package. Module analysis disclosed 17 genes associated to asthma at distinct level. Subsequent network analysis based on PCC figured out several key lncRNAs probably interacted to those key asthma-related genes, i.e., LINC02145, GUSBP2. Our functional investigation indicated that their functions might involve in immune, inflammatory response and apoptosis process.

Conclusions

Our study successfully discovered many key noncoding RNA molecules related to pathogenesis of asthma and relevant treatment, which may provide some clues for asthmatic diagnose and therapy in future.

Low-dose theophylline restores corticosteroid responsiveness in rats with smoke-induced airway inflammation

Patients with chronic obstructive pulmonary disease (COPD) respond poorly to corticosteroids. Histone deacetylase-2 (HDAC-2) plays a pivotal role in many cases of steroid insensitivity. The main aim of this study was to restore the smoking-induced reduction in corticosteroid sensitivity by increasing HDAC-2 activity using low-dose theophylline. Rats were exposed to cigarette smoke (CS) and treated with budesonide and two doses of theophylline. Besides the pathologic examination and cell counting in the bronchoalveolar lavage fluid (BALF), the expression of HDAC-2 and CXC chemokine ligand-8 (CXCL-8) were measured. Airway inflammation induced by CS was demonstrated by pathologic changes of lung tissue and increased level of CXCL-8. CS exposure also markedly decreased HDAC-2 expression. Moreover, a negative correlation was found between HDAC-2 activity and a lung destruction index. The index was restored to control levels with inhaled corticosteroid treatment in combination with a low, not a high, dose of theophylline. These results indicate that low-dose theophylline might provide protection from smoke damage and improve the anti-inflammatory effects of steroids by increasing HDAC-2 activity.