Role of PPARγ on γ-glutamylcysteine synthetase activity and expression in rats with chronic obstructive pulmonary disease
- VernacularTitle:PPARγ影响γ-谷氨酰半胱氨酸合成酶活性及表达在大鼠慢性阻塞性肺疾病中的作用
- Author:
Jie LI
;
Aiguo DAI
;
Ruicheng HU
;
Liming ZHU
;
Meifang WANG
- Publication Type:Journal Article
- Keywords:
Peroxisome proliferator-activated receptor γ;
Glutamylcysteine synthetase;
Pulmonary disease;
chronic obstructive
- From:
Chinese Journal of Pathophysiology
2010;26(2):302-308
- CountryChina
- Language:Chinese
-
Abstract:
AIM: To explore the effects of peroxisome proliferator-activated receptor γ (PPARγ) on the activity and expression of γ-glutamylcysteine synthetase (γ-GCS), and its role in rats with chronic obstructive pulmonary disease. METHODS: COPD model was established by the method of combining fumigation and lipopolysaccharide (LPS) intra-tracheal dripping. Meanwhile, some of the COPD rats were administered with rosiglitazone (RGZ), a PPARγ activator. The pulmonary function and the pathological changes were determined. ROS content and γ-GCS activity in lung tissues were detected. The levels of PPARγ, γ-GCS mRNA and protein expression in lung tissues were measured by immunohistochemistry, Western blotting, in situ hybridization (ISH) and reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The pulmonary function (FEV_(0.3), FEV_(0.3)/FVC%, PEF) were significantly improved in RGZ group compared to COPD group. Under light microscope, lung pathological changes in COPD group conformed to pathological features of COPD. The pathological changes of lung tissue were obviously reduced in RGZ group compared to COPD group. In RGZ group, ROS content was obviously reduced and γ-GCS activity significantly increased compared to COPD group. Protein and mRNA expressions of PPARγ and γ-GCS in COPD group significantly higher than those in control group (all P<0.01), and those in RGZ group was markedly increased compared to COPD group (all P<0.05). Linear correlation analysis showed that PPARγ protein was positively correlated with γ-GCS activity (r=0.634, P<0.01), and was no significantly correlated with ROS content (r=0.214, P>0.05). PPARγ protein was positively correlated with γ-GCS protein and mRNA (r=0.553, r=0.442, all P<0.01). CONCLUSION: PPARγ activation by RGZ reduces the extent of COPD oxidant/antioxidant imbalance, which plays an important role in the prevention and treatment of COPD. In addition, PPARγ may play an important antioxidant protection role by reducing ROS production, and increasing activity and gene expression of γ-GCS in the lung.