[Therapeutic effects of aerosolized signal transducer and activator of transcription 1 antisense oligonucleotide administered at different time points on bleomycin-induced pulmonary fibrosis: experiment with rats].
OBJECTIVE
To investigate the curative effects of inhaling signal transducer and activator of transcription 1 (STAT1) antisense oligonucleotide (ASON) on alveolitis and pulmonary fibrosis and the best administration time.


METHODS
Twenty-five adult female Wistar rats were randomly divided into 5 equal groups: BLM group, undergoing intra-tracheal perfusion of BLM so as to establish animal models of alveolitis and pulmonary fibrosis and then inhaling aerosolized normal saline (NS); NS group undergoing intra-tracheal perfusion of NS and then inhaling aerosolized NS; ASON 0 d group, undergoing intra-tracheal perfusion of BLM and then inhaling aerosolized STAT1 ASON 3 ml immediately; ASON 7 d group, undergoing intra-tracheal perfusion of BLM and then inhaling STAT1 ASON 3 ml 7 days later; and ASON 14 d group undergoing intra-tracheal perfusion of BLM and then inhaling aerosolized STAT1 ASON 3 ml 14 days later. Aerosolized inhalation was repeated once every other day for 4 times. Twenty-eight days after intra-tracheal perfusion the rats were sacrificed with their lungs taken out to undergo pathological examination. NS was infused into the right lungs to get bronchoalveolar lavage fluid (BALF). ELISA was used to examine the concentrations of transforming growth factor-beta (TGF-beta) and tumor necrosis factor-alpha (TNF-alpha) in the BALF.


RESULTS
The pathology result of the lung tissues showed that compared with the BLM and ASON 14 d groups, the alveolitis and pulmonary fibrosis of the ASON 0 d group were obviously milder. The scores of alveolitis and pulmonary fibrosis of the ASON 0 d group were (1.80 +/- 0.84) and (2.60 +/- 0.55) respectively, both significantly lower than those of the BLM group [(2.40 +/- 0.55) and (4.40 +/- 0.55) respectively] and those of the ASON 7 d group [(2.20 +/- 0.45) and (3.00 +/- 0.71) respectively] (all P < 0.05). The scores of pulmonary fibrosis of the ASON 7 d group was significantly lower than those of the BLM and ASON 14 d groups (both P < 0.05). The concentrations of TGF-beta and TNF-alpha in BALF of the ASON 0 d group were (48.11 +/- 3.46) pg/ml and (1.93 +/- 0.14) ng/ml respectively, both significantly lower than those of the BLM group [(57.67 +/- 2.46) pg/ml and (2.45 +/- 0.25) ng/ml respectively, both P < 0.05]. The concentration of TGF-beta in BALF of the ASON 0 d group was significantly lower than those of the ASON 7 d and ASON 14 d groups [(51.42 +/- 3.57) pg/ml and (55.8 3 +/- 1.79) pg/ml respectively, both P < 0.05]. The concentration of TGF-beta in BALF of the ASON7 d group was significantly lower than those of the BLM and ASON 14 d groups (both P < 0.05).


CONCLUSIONS
STAT1 ASON administered in the early stage helps depress the pulmonary fibrosis procedure, and the earlier the drug is administrated the better effect would be obtained. Aerosolized STAT1 ASON can be used as a therapeutic method for pulmonary fibrosis.
Li
Jing
J
Department of Respiratory Medicine, Affiliated Hospital of Luzhou Medical College, Luzhou 646000, China.
Zeng
Ming
M
Zhu
Chen
C
Wang
Wen-Jun
WJ
Zhan
Xiao-Qin
XQ
Fan
Xian-Ming
XM
D000280:Administration, Inhalation; D000818:Animals; D001761:Bleomycin / Q000009:adverse effects; D019454:Chronotherapy; D005260:Female; D016376:Oligonucleotides, Antisense / Q000008:administration & dosage*; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000628:therapy*; D051381:Rats; D017208:Rats, Wistar; D050794:STAT1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D016376:Oligonucleotides, Antisense; D050794:STAT1 Transcription Factor; C494081:Stat1 protein, rat; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; D001761:Bleomycin