Glutathione peroxidase activity in blood cells from aspirin-induced asthma patients

Application of an Integrative Drug Safety Model for Detection of Adverse Drug Events Associated With Inhibition of Glutathione Peroxidase 1 in Chronic Obstructive Pulmonary Disease

BACKGROUND

Chronic Obstructive Pulmonary Disease is characterised by declining lung function and a greater oxidative stress burden due to reduced activity of antioxidant enzymes such as Glutathione Peroxidase 1.

OBJECTIVES

The extent to which drugs may contribute to this compromised activity is largely unknown. An integrative drug safety model explores inhibition of Glutathione Peroxidase 1 by drugs and their association with chronic obstructive pulmonary disease adverse drug events.

METHODS

In silico molecular modelling approaches were utilised to predict the interactions that drugs have within the active site of Glutathione Peroxidase 1 in both human and bovine models. Similarities of chemical features between approved drugs and the known inhibitor tiopronin were also investigated. Subsequently the Food and Drug Administration Adverse Event System was searched to uncover adverse drug event signals associated with chronic obstructive pulmonary disease.

RESULTS

Statistical and molecular modelling analyses confirmed that the use of several registered drugs, including acetylsalicylic acid and atenolol may be associated with inhibition of Glutathione Peroxidase 1 and chronic obstructive pulmonary disease.

CONCLUSION

The integration of molecular modelling and pharmacoepidemological data has the potential to advance drug safety science. Ongoing review of medication use and further pharmacoepidemiological and biological analyses are warranted to ensure appropriate use is recommended.

Glutathione redox control of asthma: from molecular mechanisms to therapeutic opportunities

Asthma is a chronic inflammatory disorder of the airways associated with airway hyper-responsiveness and airflow limitation in response to specific triggers. Whereas inflammation is important for tissue regeneration and wound healing, the profound and sustained inflammatory response associated with asthma may result in airway remodeling that involves smooth muscle hypertrophy, epithelial goblet-cell hyperplasia, and permanent deposition of airway extracellular matrix proteins. Although the specific mechanisms responsible for asthma are still being unraveled, free radicals such as reactive oxygen species and reactive nitrogen species are important mediators of airway tissue damage that are increased in subjects with asthma. There is also a growing body of literature implicating disturbances in oxidation/reduction (redox) reactions and impaired antioxidant defenses as a risk factor for asthma development and asthma severity. Ultimately, these redox-related perturbations result in a vicious cycle of airway inflammation and injury that is not always amenable to current asthma therapy, particularly in cases of severe asthma. This review will discuss disruptions of redox signaling and control in asthma with a focus on the thiol, glutathione, and reduced (thiol) form (GSH). First, GSH synthesis, GSH distribution, and GSH function and homeostasis are discussed. We then review the literature related to GSH redox balance in health and asthma, with an emphasis on human studies. Finally, therapeutic opportunities to restore the GSH redox balance in subjects with asthma are discussed.

Screening and identification of the genes transactivated by human gene 2 transactivated by hepatitis C virus core protein using microarray assay

AIM: To screen and identify the up- and down-regulated genes of TAHCCP2 in the hepatocyte, and to investigate its possible function of TAHCCP2 in vivo by cDNA microarray assay.

METHODS: Suppression subtractive hybridization (SSH) and bioinformatics techniques were used for screening and cloning of the target gene TAHCCP2 transactivated by HCV core protein. Total mRNA was isolated from HepG2 cells transfected pcDNA3.1(-)-TAHCCP2 and pcDNA3.1(-) empty vector, respectively, cDNA was prepared by reverse transcription. Microarray was conducted for screening of up-and down-regulated genes of both HepG2 cells.

RESULTS: The expressive vector of pcDNA3.1(-)-TAHCCP2 was constructed and confirmed by restriction enzyme digestion and DNA sequencing. After screening with DNA microarray, we found that 4 genes were down-regulated.

CONCLUSION: The obtained sequences may be target genes transactivated by TAHCCP2, among which some genes coding proteins involve inoxidative stress, cell growth and energy metabolism. Advanced experiments need to be done to prove this finding.