高脂饮食致大鼠肺纤维化及N-乙酰半胱氨酸的抑制作用

High-fat diet induces pulmonary fibrosis in rats and inhibitory effects of N-acetylcysteine

目的 观察高脂饮食致大鼠肺纤维化及N-乙酰半胱氨酸（NAC）的抑制作用.方法 SD大鼠30只,按随机数字表法随机平均分为3组,其中高脂饮食组、NAC组每日给予高脂饮食（脂肪占71％总热量）,对照组予对照饮食（脂肪占35％总热量）,各组均用Lieber-DeCarli液体饲料单笼喂养,不再提供饮水,NAC组另外给予NAC 300 mg·kg-1·d-1灌胃.于8周后处死大鼠,HE染色观察肺组织大体改变;Masson染色观察肺间质中胶原沉积;比色法和酶联免疫法测肺组织中谷胱甘肽（GSH）和透明质酸（HA）含量,免疫组化法测肺组织中转化生长因子β1（TGF-β1）的表达.结果 肺组织病理学观察结果：高脂组肺泡及肺泡间隔炎性细胞浸润,部分肺泡壁破坏、塌陷,肺泡间隔中胶原纤维沉积增多、间隔增宽,NAC组肺泡炎症及破坏程度、间质胶原沉积情况均轻于高脂组.高脂组肺组织HA含量和TGF-β1表达均显著高于NAC组、对照组[（0.57±0.06）比（0.46 ±0.04）、（0.41±0.04） mg/g和24.6±3.4比16.8±2.6、11.7±1.5,均P＜0.05],而GSH含量均显著低于NAC组、对照组[（0.11±0.05）比（0.19±0.11）、（0.22±0.14） mg/g,均P＜0.05].结论 高脂饮食可致大鼠肺组织损伤及纤维化,NAC对其有抑制作用.

Objective To explore the relation between high-fat diet and pulmonary fibrosis and the inhibition of N-acetylcysteine （NAC） on lung tissue in rats.Methods Thirty Sprague Dawley （SD） male rats were randomly divided into control group （n =10） on a quantitative control Lieber-DeCarli liquid diet,a high-fat diet group （n =10） on a high fat-diet Lieber-DeCarli liquid diet and NAC group （n =10） on NAC 300 mg · kg-1 · d-1.All rats were sacrificed 8 weeks later.The morphological changes and collagen deposition in lung tissue were observed by hematoxylin ＆ eosin and Masson staining while the contents of glutathione （GSH） and haluronic acid （HA） measured through colorimetry and enzyme-linked immunosorbent assay.And the expression of transforming growth factor-β1 （TGF-β1） expression in lung tissue was detected through immunohistochemistry.Results There were variable degree of alveolar and alveolar septal infiltration of inflammatory cells.And more deposition of collagen fibers appeared at intervals of alveolar in high fat group.Similar pathological changes were found in NAC group,but the degree was lower than that of high-fat group.Compared to the control and NAC groups,the lung tissue content of GSH decreased （GSH：0.11 ±0.05 vs 0.19 ±0.11,0.22 ±0.14 mg/g,both P ＜0.05） while HA and TGF-β1 increased in high-fat diet group （HA：0.57 ± 0.06 vs 0.46 ± 0.04,0.41 ± 0.04 mg/g ; TGF-β1：24.6 ±3.4 vs 16.8 ± 2.6,11.7 ± 1.5,all P ＜ 0.05）.Conclusion High-fat diet may induce pulmonary fibrosis in rats and NAC has inhibitory effects.