黑木耳多糖对被动吸烟及PM2.5暴露大鼠肺损伤的拮抗

Antagonism of Auricularia auricular polysaccharide to pulmonary injury induced by passive smoking and PM in rats

目的探讨黑木耳多糖对被动吸烟所致大鼠慢性肺损伤及PM2.5短期暴露的影响。方法60只雄性SD大鼠随机分为空白对照组、模型对照组及黑木耳多糖低(50 mg/kg)、中(100 mg/kg)、高(150 mg/kg)剂量组,每组12只。对模型对照组和黑木耳多糖各剂量组大鼠每天进行被动吸烟(焦油量10 mg、尼古丁1.0 mg、一氧化碳量11 mg)2次,每次30 min;黑木耳多糖低、中、高剂量组每日灌胃相应浓度黑木耳多糖,空白对照组和模型对照组每日灌胃相同剂量的生理盐水,共28 d。实验第29、30、31天时,模型对照组和黑木耳多糖各剂量组经气道滴注PM2.5悬液(5 mg/ml)0.25 ml,每12 h给予1次;空白对照组给予相同剂量生理盐水。观察肺组织病理,检测右侧支气管肺泡灌洗液(BALF)中超氧化物歧化酶(SOD)活力、丙二醛(MDA)和一氧化氮(NO)含量及白细胞数、总蛋白含量。结果与模型对照组相比,黑木耳多糖中、高剂量组大鼠肺泡结构较完整,腔内分泌物较少,炎性细胞浸润较轻,肺毛细血管结构较完整。与模型对照组相比,黑木耳多糖低、高剂量组大鼠BALF中SOD活力升高,黑木耳多糖中、高剂量组大鼠肺泡中NO、MDA含量降低,差异有统计学意义(P<0.05)。与模型对照组相比,黑木耳多糖各剂量组大鼠BALF中总蛋白含量及白细胞数量均降低,其中总蛋白含量随着黑木耳多糖浓度的增加而降低,白细胞数量随着黑木耳多糖浓度的增加而升高,差异有统计学意义(P<0.05)。结论黑木耳多糖具有一定的抗炎、抗氧化作用,可以改善被动吸烟及PM2.5对大鼠肺组织及气道造成的损伤。

Objective To understand the protective effect of Auricularia auricula polysaccharide on lung injury induced by passive smoking and PM2.5 in rats.Methods A total of 60 male SD rats were randomly divided into the blank control group,the model control group,the A.auricula polysaccharide intervention groups[low dose(50 mg/kg)group,the moderate dose(100 mg/kg)group and the high dose(150 mg/kg)],12 in each.Each group was treated with cigarette smoke,30 min per time,two times a day,and the low,moderate and high dose group of A.auricula polysaccharide intervention were given A.auricula polysaccharide of corresponding concentration every day through gavage.The blank control group and the model group were given the same dosage of normal saline.At the 29 th,30 th day and 31 st day of the treatment,the rats in the model group and the intervention group were given 0.25 ml PM2.5 suspension(5 mg/ml)through intratracheal instillation,once every 12 hours and the blank control group was given the same dose of normal saline.At the 32 nd day,the lung tissue was collected for pathological examination,and bronchoalveolar lavage fluid(BALF)was collected from the right lung.The levels of superoxide dismutase(SOD),MDA,nitric oxide(NO),count of white blood cells,total protein in BALF were detected.Results Compared with the model control group,the alveolar structure was more complete,the endovascular secretion decreased,the inflammatory cell infiltration reduced,and the pulmonary capillary structure was more complete in moderate and high dose intervention groups,the levels of SOD increased in low and high dose intervention groups,and the levels of MDA and NO decreased in moderate and high dose intervention groups(P<0.05);In intervention groups,the total protein and the total number of white blood cells in the alveolar lavage fluid decreased significantly compared with the model group;With the increase of A.auricula exposure doses,the total protein decreased,the total number of white blood cells increased respectively.Conclusion A.auricula polysaccharide has certain anti-inflammatory and antioxidant effects,which may improve the lung tissue damage induced by passive smoking and PM2.5 in rats.