Expression of CREB-binding protein and peroxisome proliferator-activated receptor gamma during formoterol or formoterol and corticosteroid therapy of chronic obstructive pulmonary disease.

We assessed the effect of therapy on nuclear signaling related to inflammatory processes in sputum cells of patients with chronic obstructive pulmonary disease (COPD). Patients were treated with formoterol (F) or formoterol plus budesonide (F/ICS) b.i.d. for 4 weeks, their sputum cells were isolated and subjected to RNA extraction or lysis, followed by differential centrifugation. Signaling protein levels were assessed by Western blots, their specific mRNAs were quantified using qRTPCR, while 8-isoprostane levels were examined using enzyme immunoassay kit. Cytosolic 8-isoprostane levels and nuclear glucocorticoid receptor expression (protein and mRNA) were not significantly different in both groups, while nuclear cAMP response element binding protein (CREB; protein and mRNA) and peroxisome proliferator-activated receptor gamma (PPARgamma protein and mRNA) were significantly higher in cells from F/ICS-treated patients. CREB-binding protein (CBP; protein and mRNA) levels were significantly lower in F/ICS patients. These changes indicate increased anti-inflammatory signaling in F/ICS-treated patients and seem to be beneficial.

Cytoplasm-nuclear trafficking of CREB and CREB phosphorylation at Ser133 during therapy of chronic obstructive pulmonary disease.

cAMP responsive element binding protein (CREB) plays an important role in transcriptional machinery. CREB signaling is altered in patients with asthma. However, the role of CREB in chronic obstructive pulmonary disease (COPD) is less clear. In the present study we assessed changes in subcellular CREB distribution and activation (CREB-P) in 35 stable COPD patients treated with formoterol (F), formoterol+budesonide (F/ICS), and formoterol+budesonide+theophylline (F/ICS/Th) b.i.d. for 4 weeks, using SDS-PAGE/WB in cytosol and nuclear extracts of induced sputum cells. The expression of CREB was increased after F/ICS in both cytosolic and nuclear fractions by about 40% and 24%, respectively (P<0.001, P<0.01), while CREB-P increased after F/ICS by about 50% (P<0.01) in both compartments. These changes were not affected by theophylline. In F/ICS-treated patients, relative accumulation of CREB in cytosol was observed. These findings indicate, that poor response to ICS therapy may be related to increased CREB-associated signaling.

Molecular basis of chronic inflammation in lung diseases: new therapeutic approach.

There is increasing evidence that histone acetylation, controlled by histone acetyltransferases (HAT), reversed by histone deacetylases (HDAC) plays a critical role in the process of regulation of inflammatory genes and in mediating the anti-inflammatory effects of corticosteroids in asthma patients. There is evidence of an increase in HAT activity in asthmatics, which leads to increased expression of multiple inflammatory genes that are regulated by proinflamatory factors, such as nuclear factor NF-kappaB. Reduction in HDAC activity, secondary to oxidative and nitrative stress and severe inflammation, may account for the amplified inflammation in chronic obstructive pulmonary disease (COPD). Corticosteroids switch off inflammatory genes through the inhibition of HAT activity and by recruitment of HDAC2 to the activated transcription complex. Several new strategies to control inflammations in COPD, aiming at restoration of the HDAC-2 activity and/or mitigation of HAT-related signaling are in the preclinical and clinical development.