The effects of dexamethasone and betamethasone on surfactant protein-B messenger RNA expression in human type II pneumocytes and human lung adenocarcinoma cells.
OBJECTIVE
The purpose of this study was to compare the effect of a single 48-hour exposure to betamethasone or dexamethasone in the NCI-H441 cell line and in human type II pneumocytes.


METHODS
NCI-H441 cells were exposed 48 hours to varying concentrations of betamethasone or dexamethasone (10(-10) to 10(-7) mol/L) alone or in combination with 1 mmol/L dibutyryl cyclic adenosine monophosphate. Likewise, human type II pneumocytes were exposed 48 hours to varying concentrations of betamethasone or dexamethasone (10(-9) to 10(-7) mol/L) alone or in combination with 1 mmol/L dibutyryl cyclic adenosine monophosphate. The measured outcome was the stimulatory effect on surfactant protein B gene transcription as expressed by surfactant protein B messenger RNA accumulation. The experiment was conducted 5 times in NCI-H441 cells and 6 times in type II cells, in parallel with control. Surfactant protein B messenger RNA was determined at control level and 48 hours after exposure by quantitative reverse transcription-polymerase chain reaction.


RESULTS
A similar dose-dependent response in surfactant protein B messenger RNA expression was seen with both betamethasone and dexamethasone. In human type II pneumocytes, the inductive profile of surfactant protein B messenger RNA after 48-hour exposure to betamethasone or dexamethasone was similar to that seen in the NCI-H441 cells.


CONCLUSIONS
Dexamethasone and betamethasone achieved similar dose-response patterns of surfactant protein-B expression in vitro.
Ramin
Susan M
SM
Department of Obstetrics, Gynecology and Reproductive Sciences, Division of Maternal-Fetal Medicine, University of Texas-Houston Medical School, 77030, USA. susan.m.ramin@uth.tmc.edu
Vidaeff
Alex C
AC
Gilstrap
Larry C
LC
Bishop
Karen D
KD
Jenkins
Gaye N
GN
Alcorn
Joseph L
JL
D000230:Adenocarcinoma / Q000473:pathology; D001623:Betamethasone / Q000008:administration & dosage / Q000494:pharmacology*; D045744:Cell Line, Tumor / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects; D000242:Cyclic AMP / Q000008:administration & dosage; D003907:Dexamethasone / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D005938:Glucocorticoids / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D008168:Lung / Q000166:cytology / Q000187:drug effects / Q000196:embryology; D008175:Lung Neoplasms / Q000473:pathology; D016133:Polymerase Chain Reaction; D037701:Pulmonary Surfactant-Associated Protein B / Q000187:drug effects* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D020545:Respiratory Mucosa / Q000187:drug effects
D005938:Glucocorticoids; D037701:Pulmonary Surfactant-Associated Protein B; D012333:RNA, Messenger; D003907:Dexamethasone; D001623:Betamethasone; D000242:Cyclic AMP