慢性饮酒对大鼠肺组织及TGF-β1表达的影响

Effect of chronic alcohol ingestion on lung tissue and expression of TGF-β1 in lung tissue of rats

目的通过观察慢性饮酒大鼠的肺组织及转化生长因子β1（TGF-β1）等指标的变化，以探讨酒精与肺纤维化之间的关系及可能的机制。方法健康雄性SPF级Sprague-Dawley大鼠20只，随机分成2组，每组10只。对照组每日给予定量无酒精液体饲料单笼喂养；酒精组每日给予定量酒精液体饲料单笼喂养，不再提供饮水。16周后，通过Masson染色观察肺间质中胶原沉积的情况，通过透射电镜观察肺组织超微结构改变。用比色法计算大鼠肺组织中谷胱甘肽（GSH）和羟脯氨酸（HYP）的含量，采用实时荧光定量PCR技术检测肺组织TGF-β1表达水平。结果Masson染色结果显示，酒精组较对照组在肺泡间隔中胶原纤维沉积增多。电镜观察结果显示，酒精组较对照组Ⅱ型肺泡上皮微绒毛、嗜锇性板层小体数量减少，线粒体膜和嵴融合、模糊不清，细胞间隔可见胶原纤维沉积。与对照组比较，酒精组肺组织GSH含量减少，HYP含量增加，差异均有统计学意义（t值分别为2．893、5．697，P值均〈0．05）。与对照组比较，酒精组肺组织TGF-β1表达量升高（t=3．811，P〈0．05）。结论慢性饮酒可以引起大鼠肺间质改变，肺组织中TGF-β1的表达升高。慢性饮酒可能是引起大鼠肺纤维化的原因之一。

Objective To investigate the relationship between alcohol and pulmonary fibrosis and possible mechanism by observing the effect of chronic alcohol intake on lung tissues in rats and transforming growth factor-β1 （TGF-β1）. Methods Twenty clean healthy male Sprague-Dawley rats, weighing 160-200 g, were randomly divided into control group （ n = 10） and alcohol group （ n = 10）, and fedquantitative non-ethanol or ethanol Lieber-DeCarli liquid diet every day in a single cage for 16 weeks. Histological change of lungs was evaluated by hematoxylin-eosin stain and transmission electron microscope（TEM）. Results （1）Masson results showed that the alcohol group had more deposition of collagenfibers at intervals of alveolar than the control group. （2）In TEM, mitochondrial membrane fused and fuzzy structure and collagen fiber deposition in cell compartment in different levels were observed in alcohol group. （3）Compared to the control group, the content of glutathione in rat lung tissue reduced but hydroxyproline increased in the alcohol group, the differences were statistically significant （ t = 2. 893, 5. 697, respectively, aU P 〈0.05）. （4）TGF-β1 in rat lung tissue of alcohol group was higher than that of control group, the differences were statistically significant （ t = 3. 811, P d0.05）. Conclusions Chronic alcohol ingestion can cause collagen deposition in alveolar interval and higher expression of TGF-β1 in lung tissue. Alcohol may be one of the reasons for pulmonary fibrosis in rats.