姜黄素干预对博莱霉素诱导的大鼠肺纤维化的影响

The effect of curcumin on bleomycin-induced pulmonary fibrosis in rats

目的利用博莱霉素诱导的大鼠肺纤维化模型观察姜黄素对肺纤维化的作用效果及其机制。方法 54只大鼠按随机数字表法分为正常对照组、博莱霉素组和姜黄素组,每组18只。正常对照组:于实验0 d 气管内一次性注入生理盐水2 ml/kg,第14天起每日腹腔注射生理盐水0.5 ml/kg;博莱霉素组:气管内一次性注入博莱霉素 A_5制剂5 mg/kg,第14天起每日腹腔注射6%乙醇和6%聚乙二醇混合溶液0.5 ml/kg;姜黄素组:气管内一次性注入博莱霉素 A_5制剂5 mg/kg,第14天起每日腹腔注射姜黄素(溶于6%乙醇和6%聚乙二醇混合溶液)50 mg/kg。分别于第17、21、28天各取6只大鼠处死,取肺组织行苏木精-伊红(HE)和 Masson 染色以观察其病理变化;用逆转录-聚合酶链反应(RT-PCR)法测定肺组织中转化生长因子β_1(TGF-β_1)和γ干扰素(IFN-γ)mRNA 表达;用消化法测定羟脯氨酸含量,收集支气管肺泡灌洗液(BALF)测定 TGF-β_1、IFN-γ的含量。结果(1)肺泡炎评分:姜黄素组与博莱霉素组在第28天分别为(1.3±0.5)分、(2.0±0.9)分,两组比较差异有统计学意义(q=3.26,P<0.05);(2)肺纤维化评分:姜黄素组与博莱霉素组在第21天分别为(1.3±0.5)分、(1.8±0.4)分,第28天分别为(1.2±0.4)分、(2.2±1.0)分,两组比较差异有统计学意义(q 值分别为3.33、4.00,P 均<0.05);(3)肺组织羟脯氨酸含量:姜黄素组与博莱霉素组在第28天分别为(1.75±0.36)μg/g、(2.47±0.24)μg/g,两组比较差异有统计学意义(q=7.20,P<0.01);(4)BALF 中 TGF-β_1含量:姜黄素组与博莱霉素组在第21天分别为(20±3)ng/L、(39±7)ng/L,第28天分别为(24±4)ng/L、(40±7)ng/L,两组比较差异有统计学意义(q 值分别为5.30、6.27,P 均<0.05);(5)肺组织中 TGF-β_1mRNA 的表达:姜黄素组与博莱霉素组在第21天分别为0.51±0.11、0.59±0.13,第28天分别为0.50±0.07、0.64±0.11,两组比较差异无统计学意义(q 值分别为1.55、3.13,P 均>0.05);(6)BALF 中 IFN-γ含量:姜黄素组与博莱霉素组在第21天分别为(28±5)ng/L、(35±13)ng/L,第28天分别为(30±11)ng/L、(39±13)ng/L,两组比较差异无统计学意义(q 值分别为1.85、2.03,P 均>0.05);(7)肺组织中 IFN-γ mRNA 的表达:姜黄素组与博莱霉素组在第21天分别为0.49±0.17、0.50±0.08,第28天分别为0.52±0.15、0.52±0.11,两组比较差异无统计学意义(q 值分别为0.17、0.00,P 均>0.05)。结论姜黄素可减轻博莱霉素诱导的大鼠肺泡炎和肺纤维化,其作用机制可能与抑制 TGF-β_1有关。

Objective To observe the effect and mechanism of curcumin on pulmonary fibrosis induced by bleomycin in rats. Methods Fifty-four SD rats were randomly divided into 3 groups, 18 rats each group. The control group received a single intratracheal dose of 2 ml/kg of sterile physiological saline at day 0, and from 14 d, 0. 5 ml/kg of sterile physiological saline intraperitoneally every day. The bleomycin group received a single intratracheal dose of 5 mg/kg of bleomycin As, and from 14 d, 0. 5 ml/kg of suspension of 6% alcohol and 6% polyethylene glycol intraperitoneally every day. The curcumin group received a single intratracheal dose of 5 mg/kg of bleomycin A5, and from 14 d, 50 mg/kg of curcumin （suspended in 6% alcohol and 6% polyethylene glycol） intraperitoneally every day. Six rats in each group were killed at day 17,21,28 in batches. The sections of lungs were stained with hematoxylin-eosin （HE）and Masson＇ s trichrome to evaluate the severity of alveolitis and pulmonary fibrosis. The content of hydroxyproline and the expression of transforming growth factor-β1 （TGF-β1） mRNA, interferon-γ（IFN-γ） mRNA in lung tissues were analyzed. The concentration of TGF-β1 and IFN-γ in bronchoalveelar lavage fluid （BALF） were measured. Results （ 1 ） The scores of alveolitis in the curcumin group and the bleomycin group at day 28 were 1.3 3= 0. 5,2. 0 3= 0. 9, respectively, the difference being significant （ q = 3.26, P 〈 0. 05）. （2） The scores of pulmonary fibrosis in the curcumin group and the bleomycin group were 1.3 3= 0. 5,1.8 3= 0. 4 at day 21, and 1.2 3= 0. 4,2. 2 3= 1.0 at day 28, the difference being significant between the two groups （ q = 3.33,4. 00, all P 〈 0. 05 ）. （ 3 ） The content of hydroxyproline in lung tissues in the curcumin group and the bleomycin group were （ 1.75 3±0. 36 ） μg/g, （2. 47 3±0. 24 ） μg/g at day 28, the difference beingsigniticant （q =7.20,P 〈0. 01 ）. （4）The concentration of TGF-β1 in BALF in the cureumin group and the bleomycin group were （20 ±3） ng/L,（39±7） ng/L at day 21 ,and （24±4） ng/L, （40 ± 7 ） ng/L at day 28, all being statistically different between the two groups （ q = 5. 30,6. 27, all P 〈 0. 05 ）. （5） The expression of TGF-β1 mRNA in lung tissues in the curcumin group and the bleomycin group were 0.51 3=0. 11,0.59 3=0. 13 at day 21,and 0.50 ±0.07,0. 64±0. 11 at day 28, all being not statistically different between the two groups （ q = 1.55,3.13, all P 〉 0. 05 ）. （ 6 ）The concentrations of IFN-γ in BALF in the curcumin group and the bleomycin group were 0. 49 3= 0. 17,0. 50 3= 0. 08 at day 21, and 0. 52 3= 0. 15, 0. 52 3= 0. 11 at day 28, all being not statistically different between the two groups（ q = 1.85, 2. 03 , all P 〉 0. 05）. （7） The expression of IFN-γ mRNA in the curcumin group and the bleomycin group were （28±5） ng/L, （35±13 ） ng/L at day 21, and （30± 11 ） ng/L, （39±13 ） ng/L at day 28, no significant difference between the two groups （ q = 0. 17, 0. 00, all P 〉 0. 05 ）. Conclusions Cureumin can alleviate alveolitis and pulmonary fibrosis induced by bleomycin in rats, possibly through its inhibition of TGF-β1.