The Relationship Between Oncostatin M With Airway Remodeling Of Asthmatic Rat

OBJECTIVE:To observe the expression of Oncostatin M (OSM) in airway of asthamatic rat and to explore the relationship between Oncostain M and airway remodeling. Oncostain M may be a novel target in asthma prevention and treatmentMETHODS:30wistar rats were selected which were male,healthy,8-weeks old,wt:200-220g.30wistar rats were divided into two groups randomly and equally:Control group, asthma group. Since the1st day, the arthma group were given intraperitioneal injection of OVA100mg complexed with alumium hydroxide200mg and killed Baccillus pertussis6×109. Since the15th day, they were exposed to aerosolize1%OVA for20-30minutes once every day,and which would last for8weeks The asthmatic model was established.Regarding the control group, since the1st day they were given intraperitioneal injection of0.9%NS2ml, and since the15th day, they were exposed to the0.9%NS during the whole experiment, and the rest treatment was the same as that for the asthma group.Twenty-four hours after the last exposure, bronchial alveolar lavage fluid(BALF)was acquired to count against different kinds of inflammation cells o And the lung tissue was collected. The morphological change of airway was detected by HE staining. The expression level of Oncostain M was detected by immuneoph-istochemically staining with Computer-based Image Analysis System. Meantime, RT-PCR was adopted to detect the level of OSM mRNA in the lung tissue.RESULTS:(1) The infiltration of eosinophils in BALF from the asthma group (9.21±1.24) increased significantly as Compared with that in the control group (0.71±0.01, p＜0.01). The infiltration of macrophges、 neutrophils、 lymphocytes in BALF from the asthma group [(64.81±2.52)(11.52±2.02)(13.24±3.26),rspectively] did not present significant difference (all p>0.05) when compared with that from the control group [(80.19±2.02)(9.14±2.57)(10.54±1.50),respectively].It demonstrated the asthmatic models were successful by pathology.(2) The WAt/Pbm, Wai/Pbm, Wam/Pbm in the asthma group [(132.06±6.13)(81.52±1.55)(43.71±5.67), respectively] increased significantly when Compared with those from the Control group [(79.84±2.40)(61.12±3.81)(16.78±2.13),respectively](all p<0.05).(3)The mRNA level of Oncostain M in the asthma group (0.95±0.04) presented significant difference when compared with that from the control group (0.45±0.16, p<0.01);(4) The expression of positive cell by immunophistochemically in the asthma group (0.34±0.13) was higher than that from the control group (0.15±0.05, p<0.01);(5) The expression level of OSM in the airway wall of asthma group correlated positively with WAt/pbm, Wai/pbm, Warn/pbm (r=0.768、0.532、0.745, all p<0.05),but those of the control group did not correlate with the expression level of OSM (R=-0.135、-0.308、-0.325. all p>0.05);(6) The expression level of OSM in the asthma group correlated positively with the number of eosinophils (R=0.970, p=0.000),and the number of neutrophils、 lymphocytes、 macrophages did not correlate with the expression of OSM (R=0.0200.180、-0.256, all p>0.05).CONCLUSION:The expression of OSM in the asthamtic model group is higher than that of the control group and correlate positively with WAt/Pbm, Wai/Pbm, Wam/Pbm and the number of eosinophils in BALF, which hint that OSM may be involved in the airway inflammation and airway remodeling in the asthma rat.