Expression of nuclear factor-kB and intervention of resveratrol in rats with pulmonary fibrosis

Abstract

Objective To observe the effect of resveratrol on bleomycin-indueed pulmonary fibrosis in rats and the expression of nuclear factor-kB （NF-kB）. Methods 90 female SD rats were randomly divided into control group, model group, low （25 mg/kg）,middle （50 mg/kg）, and high （100 mg/kg） resveratrol treated group, dexamethasone （3 mg/kg）-treated group. Rats with pulmonary fibrosis were reproduced by intratracheal injection of bleomycin. The changes of inflammation and fibrosis in lung tissues of all groups were observed. The content of hydroxyproline in lung tissues was detected. The expression of NF-kB protein in lung tissue was determined by immunohistoehemistry. Results （1）In the pathogenesis of pulmonary fibrosis in the experimental rats, there was showing the typical alveolitis （7 d）, fibrous tissue hyperplasia （14 d）, stable pulmonary fibrosis （28 d）, and other performances. （2） Compared with the control group [（265.20±8.90） ug/g,（325. 60±31. 26） ug/g,（325. 80±48. 75） ug/g], the content of hydroxyproline increased with the progression of fibrosis in the model group [（486.00±36.15） ug/g, （770. 60± 63. 29） ug/g,（1 065.00±181.31） ug/g ]and low resveratrol-treated group [（454.80±46. 610） ug/g,（803.20± 126.96） ug/g,（962.00±184.12） ug/g ]on the 7th,14th,and 28th day. The content of hydroxyproline in the middle [（376.60±30.15） ug/g, （510.00± 76.66） ug/g, （ 596.40± 139.00） ug/g] and high resveratrol-treated group [（363.80±27. 31） ug/g, （511.40±43.62） ug/g, （530.20 ± 161.04） ug/g] and the dexamethasone-treated group [（349.60 ± 41.53） ug/g, （475.60±38.64） ug/g,（524.80±135.89） ug/g] had the same trends with that in the model group and the low resveratrol-treated, but was less than them （allP 〈0.05）. （3）The expression of NF-kB protein on the 7th, 14th, and 28th day in the model group（28.02± 1.36,42.22±1.29,54.33±0.58） and low resveratrol-treated group（27.61±1.28,42.16±0. 99,53.86±0.76） was higher than that in the control group （2.89±0.19,3.01 ±0.33,2.90±0.28,all P 〈0.05）, and showed the trend of gradually increasing. The middle （23.67 ± 0. 59, 28. 38±0. 64, 34.28 ± 1.08） and high resveratrol-treated group （23.04 ± 1.46, 27.80 ± 1.48, 33.92±0.96） and the dexamethasone treated group（22.14 ± 2.14, 27.22 ±1.89,33.18 ±1.44）had the same trends with the model group and the low resveralrol-treated group, but lower than them （all P 〈0.05）. Conclusions High expression of NF-kB plays an important role in the pathogenesis of pulmonary fibrosis. Resveratrol can inhibit the expression of NF-kB, which may be one of the mechanisms of prevention and treatment of lung fibrosis. Key words: Pulmonary fibrosis ; Nuclear factor-kB ; Resveratrol ; Rat