Effects of dexamethasone on mucin gene expression in cultured human nasal epithelial cells.
OBJECTIVE
To clarify 1) which mucin gene expression is influenced by glucocorticoid and 2) whether glucocorticoid influences steady-state mucin expression or mucin gene expression induced by lipopolysaccharide.


METHODS
Dissociated cells obtained from nasal polyps were cultured on a collagen gel substrate in an air-liquid interface. Dexamethasone was added to the culture medium in the steady-state and prior to the stimulation by LPS. RNAs were extracted from culture cells, and semiquantitative reverse transcriptase-polymerase chain reaction was performed for MUC2, MUC5AC, MUC5B, MUC8, and beta-actin.


RESULTS
Dexamethasone did not influence steady-state messenger RNA levels of either mucin gene. Dexamethasone suppressed lipopolysaccharide-induced messenger RNA levels of MUC8.


CONCLUSIONS
Glucocorticoid does not influence steady-state mucin gene expression but suppresses mucin gene expression induced by secretagogues such as lipopolysaccharide.
Ishinaga
Hajime
H
Department of Otorhinolaryngology, Mie University School of Medicine, Tsu, Mie, Japan. hajime@clin.med.mie-u.ac.jp
Takeuchi
Kazuhiko
K
Kishioka
Chikako
C
Yagawa
Mayuko
M
Majima
Yuichi
Y
D002478:Cells, Cultured; D003907:Dexamethasone / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D005938:Glucocorticoids / Q000494:pharmacology*; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D009077:Mucins / Q000187:drug effects* / Q000235:genetics*; D009297:Nasal Mucosa / Q000166:cytology* / Q000187:drug effects*
D005938:Glucocorticoids; D008070:Lipopolysaccharides; D009077:Mucins; D003907:Dexamethasone