title: [Effect of total flavonoids from astragalus complanatus on paraquat poisoning-induced pulmonary fibrosis in rats and its mechanisms].
abstract: OBJECTIVE
  To investigate the effects of total flavonoids from astragalus complanatus (FAC) on paraquat poisoning-induced pulmonary fibrosis in rats.
  
  
  METHODS
  The rats were divided into six groups randomly: control group, paraquat group, prednisolone group and FAC low-dose, middle-dose, high-dose group. Pulmonary fibrosis model was replicated by intratracheal injection of paraquat. In the mext day,the rats were treated by intragastric administration once a day. After 28 days, the rats were sacrificed. The lung index and the levels of HYP and T-AOC were measured, and the pathologic changes of the lung tissue were obtained by HE staining. The levels of TGF-β, Smad2, α-SMA protein were analyzed by Western blot.
  
  
  RESULTS
  FAC improved the activity of T-AOC in serum and reduced pulmonary index and the content of HYP as well (P<0.05 or P<0.01), the alveolitis and fibrosis extent were attenuated. The expression of Smad2 significantly decreased in groups of FAC low-dose, middle-dose and high-dose (0.31±0.11, 0.45±0.12 and 0.30±0.05) as compared with that of the PQ group (0.85±0.34) (P<0.05). The expression of α-SMA significantly decreased in groups of FAC low-dose, middle-dose and high-dose (0.31±0.11, 0.35±0.07 and 0.32±0.10) as compared with that of the PQ group (0.45±0.08) (P<0.05). The expression of TGF-β significantly decreased in groups of FAC low-dose, middle-dose and high-dose (0.35±0.04, 0.27±0.05 and 0.18±0.04)as compared with that of the PQ group (0.63±0.11) (P<0.05).
  
  
  CONCLUSIONS
  FAC can alleviate PQ-induced pulmonary fibrosis in rats through inhibiting TGF-β/Smad signaling pathway.
authors.affiliation: Department of Critical Care Medical, People's Hospital of Chongqing Ba'nan District, Chongqing 401320, China.
authors.forename: Zhijian
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Critical Care Medical, People's Hospital of Chongqing Ba'nan District, Chongqing 401320, China.
authors.forename: Yaoyao
authors.initials: Y
authors.lastname: Dong
authors.affiliation: Department of Critical Care Medical, People's Hospital of Chongqing Ba'nan District, Chongqing 401320, China.
authors.forename: Yunfan
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Department of Critical Care Medical, People's Hospital of Chongqing Ba'nan District, Chongqing 401320, China; E-mail: plbbnicu@yeah.net.
authors.forename: Libo
authors.initials: L
authors.lastname: Peng
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D027883:Astragalus Plant / Q000737:chemistry*; D005419:Flavonoids / Q000494:pharmacology*; D008168:Lung / Q000473:pathology; D010269:Paraquat / Q000506:poisoning*; D064209:Phytochemicals / Q000494:pharmacology; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000188:drug therapy*; D051381:Rats; D051899:Smad2 Protein / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism
chemical_list: D000199:Actins; D005419:Flavonoids; D010269:Paraquat; D064209:Phytochemicals; D051899:Smad2 Protein; D016212:Transforming Growth Factor beta; C497784:Smad2 protein, rat; C498862:Acta2 protein, rat