[Effects of dexamethasone on intracellular expression of Th17 cytokine interleukin 17 in asthmatic mice].
OBJECTIVE
To study the effects of dexamethasone on intracellular expression of Th17 cytokine interleukin 17 and the mechanisms in asthmatic mice.


METHODS
Experimental asthma was induced by ovalbumin (OVA) sensitization in 20 in female Balb/c mice with (dexamethasone group, n=10) or without dexamethasone treatment (model group, n=10), with another 10 serving as the control group. The levels of IL-17 in the bronchoalveolar lavage fluid (BALF) and serum of the mice were measured by enzyme-linked immunosorbent assay (ELISA), and the airway inflammation was evaluated by HE staining. The expressions of IL-17 and RORgammat mRNA were measured by reverse transcription-polymerase chain reaction (RT-PCR), and the expression of RORgammat protein was measured by immunohistochemical staining.


RESULTS
The levels of RORgammat and IL-17 mRNA and protein in the asthmatic model group were significantly higher than those in the control group (P<0.01), and the increased expressions of RORgammat and IL-17 mRNA and protein in the asthmatic mice were significantly reduced by dexamethasone treatment (P<0.05).


CONCLUSIONS
Dexamethasone can inhibit the release of IL-17 probably by inhibiting RORgammat expression and blocking Th17 differentiation in asthmatic mice.
Hu
Si-Ming
SM
Department of Respiratory Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China. wing0991@sina.com
Luo
Ya-Ling
YL
Lai
Wen-Yan
WY
Chen
Pei-Fen
PF
D000818:Animals; D001249:Asthma / Q000139:chemically induced / Q000276:immunology* / Q000378:metabolism; D003907:Dexamethasone / Q000494:pharmacology*; D005260:Female; D020381:Interleukin-17 / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3 / Q000378:metabolism; D010047:Ovalbumin; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology / Q000378:metabolism*
C098680:Il17a protein, mouse; D020381:Interleukin-17; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; D012333:RNA, Messenger; D003907:Dexamethasone; D010047:Ovalbumin