[Effect of dexamethasone on expression of fractalkine in lipopolysaccharide-induced acute lung injury].
OBJECTIVE
To investigate the effect of dexamethasone on the expression of fractalkine (FKN) in lipopolysaccharide (LPS)-induced acute lung injury (ALI).


METHODS
The rat model of ALI was established by injection of LPS at the dose of 4 mg/kg. 42 Wistar rats were randomly divided into the normal group (n=6), LPS group (n=18), and dexamethasone (DEX) group (n = 18), and then the rats in both LPS and DEX groups were divided into three subgroups (1 h, 2 h and 4 h after injection of LPS), respectively. The pathological condition and the wet/dry ratio (W/D) of the lung were observed, and serum TNF-alpha level, and FKN mRNA of the lung were detected with ELISA and RT-PCR.


RESULTS
The W/D, serum TNF-alpha level, and FKN mRNA of the lung were significantly increased in LPS group, compared with those in normal group (all P < 0.05), but the W/D, serum TNF-alpha level, and FKN mRNA of the lung in the DEX group were much more decreased than those in the LPS group (all P < 0.05). In addition, the expression of FKN mRNA in the lung tissue positively correlated with the concentration of TNF-alpha (r = 0.674, P <0.05).


CONCLUSIONS
The findings suggested that pre-treatment with dexamethasone could inhibit the TNF-alpha level and prevent the increase of the expression of FKN mRNA, which may be one of the mechanisms by which DEX serves as a protection against LPS-induced lung injury.
Wang
Lei
L
Department of Respiratory Medicine, West China Hospital, Sichuan University, Chengdu 610041, China
Li
Ting-Qian
TQ
Xiang
Guo-Xia
GX
Wang
Gang
G
D000818:Animals; D054428:Chemokine CX3CL1; D020523:Chemokines, CX3C / Q000096:biosynthesis* / Q000235:genetics; D003907:Dexamethasone / Q000494:pharmacology*; D005260:Female; D008070:Lipopolysaccharides; D008168:Lung / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012128:Respiratory Distress Syndrome / Q000139:chemically induced / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D054428:Chemokine CX3CL1; D020523:Chemokines, CX3C; C515540:Cx3cl1 protein, rat; D008070:Lipopolysaccharides; D008565:Membrane Proteins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D003907:Dexamethasone