Expression of the glucocorticoid receptor alpha and beta isoforms in human nasal mucosa and polyp epithelial cells.
The lower sensitivity of the inflamed nasal mucosa to glucocorticoids might be related to an increased expression of the glucocorticoid receptor (GR) beta isoform. We investigated GRalpha and GRbeta mRNA expression in epithelial cells from nasal mucosa and nasal polyps. GRalpha mRNA was at least 1000 times more expressed than GRbeta mRNA in both tissues. GRbeta expression (mean+/-SEM of 10(3) cDNA copies/microg of total RNA) was higher in nasal polyps (1.15+/-0.19; n=27; P<0.01) than in nasal mucosa (0.62+/-0.10; n=32). Nasal polyps with > 3% of inflammatory cells had higher GRbeta levels (1.40+/-0.29; n=16) than both nasal mucosa (P<0.01) and polyps with < or = 3% of inflammatory cells (0.80+/-0.18; n=11; P<0.05). No difference in GRbeta expression was found between nasal mucosa and polyps with < or = 3% of inflammatory cells. GRbeta expression correlated with the inflammatory cell number, especially with mast cells (r=0.50, P<0.0001). There was no difference in GRalpha mRNA expression between nasal mucosa and nasal polyps. In summary, GRalpha is far more expressed than GRbeta in both tissues. The increased expression of GRbeta may be related to the presence of inflammatory cells.
Pujols
Laura
L
Institut d'Investigacions Biomèdiques August Pi i Sunyer, Catalonia, Spain.
Mullol
Joaquim
J
Benítez
Pedro
P
Torrego
Alfons
A
Xaubet
Antoni
A
de Haro
Josep
J
Picado
César
C
D000328:Adult; D004847:Epithelial Cells; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000378:metabolism*; D009298:Nasal Polyps / Q000378:metabolism*; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000378:metabolism; D011965:Receptors, Glucocorticoid / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods
D020033:Protein Isoforms; D012333:RNA, Messenger; D011965:Receptors, Glucocorticoid; C411470:glucocorticoid receptor alpha; C121943:glucocorticoid receptor beta