Expression Of γ-GCS And TGF β₁ In Pulmonary Tissue Of Experimental Smoking Rat

Objective:To evaluate the role of TGFβ₁ in course of oxidant/antioxidant of smoking rat in COPD by observing the expression of protein and mRNA of γ-GCS and TGFβ₁ and the relationship between them. Method:Rat smoking device was performed byself.40 rats were divided into 4 groups: non-smoking group, one-month smoking group, two-month smoking group, three-month smoking group,10 rats in each group. Compare bronchial epithelia and macrophages change of 4 groups .The expression of γ-GCSh and TGFβ₁ protein were measured by immuno histochemistry stain respectively and expression of γ-GCSh and TGFβ₁ mRNA were measured by hybridization. In addition, the mRNA expression of γ-GCSh and TGFβ₁ in pulmonary tissue were examined by RT-PCR. Result:There was typical pathologic change of chronic bronchitis and COPD in three-month smoking group.(1)The expression of γ-GCSh and TGFβ₁ protein in bronchial epithelia for one-month smoking group(0.275±0.051,0.459±0.043 ),two-month smoking group(0.497±0.067,0.559±0.051) and three-month smoking group(0.847±0.088,0.787±0.071),they all increased significantly as compared to non-smoking group(0.186±0.025,0.195±0.029)(P<0.01=. (2)The expression of γ-GCSh and TGFβ₁ mRNA in bronchial epithelia for one-month smoking group(0.530±0.049,0.494±0.067), two-month smoking group(0.786±0.065,0.792±0.065) and three-month smoking group(1.187±0.198,1.099±0.147),they all increased significantly as compared to non-smoking group(0.273±0.056,0.240±0.057)(P<0.01=.(3)The expression of γ-GCSh and TGFβ₁ protein in macrophages for one-month smoking group(23.94%±3.016%,20.72%±2.214%), two-month smoking group(33.97%±2.943%,31.76%±3.734%) and three-month smoking group(55.82%±4.872%,44.74%±4.861%), they all increased significantly as compared to non-smoking group (15.28%±1.817%,13.76%±2.753%)(P<0.01).(4) The expression of γ-GCSh and TGFβ₁ mRNA in pulmonary tissue for one-month smoking group(0.749±0.120,0.695±0.112), two-month smoking group(0.902±0.159,0.926±0.137)and three-month smoking group(1.112±0.138,1.067±0.168), they all increased significantly as compared to non-smoking group(0.449±0.107,0.602±0.097)(P<0.05).(5) As smoking time extended, the expression of γ-GCSh and TGFβ₁ in pulmonary tissue increased gradually. (6)The expression of γ-GCSh mRNA and protein in bronchial epithelia correlated with the level of TGFβ₁ in one–month smoking group and three-month smoking. The expression of γ-GCSh protein in macrophages correlated with the level of TGF β 1 in one–month smoking group and three-month smoking. The expression of γ-GCSh mRNA in pulmonary tissue correlated with the level of TGFβ₁ in three-month smoking. Conclusion:As smoking time extended, the expression of γ-GCS and TGFβ₁ in pulmonary tissue increased gradually and there was correlation between them. Maybe TGFβ₁ play a great role in oxidant/antioxidant process in COPD resulted from smoking.