铁苋菜乙醇提取物抗流感活性及其机理的初步研究

Anti-influenza Activity of Acalypha australis L. Ethanol Extract and Its Mechanism

研究铁苋菜乙醇提取物对感染流感病毒小鼠肺部、流感病毒神经氨酸酶活性及其抗氧化活性的影响。采用鼻腔接种建立流感病毒感染的小鼠肺炎模型,观察各组小鼠的肺部病理变化。并以2-(4-methylumbelliferyl)-α-D-N-acetylneuraminic acid(MUNANA)为底物,检测铁苋菜乙醇提取物高、中和低剂量组对流感病毒神经氨酸酶活性的影响。利用NO法、DPPH法和β-胡萝卜素漂白法测定了铁苋菜乙醇提取物抗氧化活性。结果显示,在动物实验中,与空白组相比,模型组小鼠肺泡、细支气管等正常的组织结构遭到破坏。与模型组相比,奥司他韦组和铁苋菜乙醇提取物高、中、低剂量组均能明显改善感染的小鼠肺部病理损伤,且改善效果呈明显剂量依赖关系。在流感病毒神经氨酸酶活性抑制实验中,与模型对照组相比,铁苋菜高、中、低剂量组均能明显抑制神经氨酸酶活性(P<0.01),高剂量组对其活性的抑制率可达60.48%。铁苋菜乙醇提取物有较好的清除DPPH、NO自由基和抑制β-胡萝卜素氧化活性。研究说明铁苋菜乙醇提取物可能抑制流感病毒神经氨酸酶的活性和抗氧化减轻流感所致的相关炎症损伤。

To investigate the effects of Acalypha australis L. ethanol extract on influenza virus-induced lung inflammation in mice,activity of influenza virus neuraminidase and its antioxidant activities,the influenza virus-infected lung inflammation model mice was established by intranasal inoculation,followed by the observation of pathological changes of lung tissue in mice. The inhibition activity of high,medium and low dosage groups on influenza virus neuraminidase were detected by the substrate of 2-（ 4-methylumbelliferyl）-α-D-N-acetylneuraminic acid（ MUNANA）,as well as its antioxidant activities were evaluated by Nitric Oxide,DPPH scavenging and β-carotene-linoleic acid bleaching assays. The results showed that compared with the blank control group,in vivo,the normal tissues of alveolar and bronchioles in model group mice was destroyed. Compared with model group,oseltamivir group and the high,medium and low dose groups of A. australis ethanol extract can obviously promote the pathological damage of lung tissue of mice in dose-dependent manner. In the assay of influenza virus neuraminidase inhibiting activity,compared with model control group,the fluorescence value of A. australis ethanol extract groups significantly decreased（ P〈0. 01） and the inhibition rate of high dose group reached 60. 48%. In addition,the A. australis ethanol extract possessed potential antioxidant activities. In conclusion,A. australis ethanol extract can alleviate influenza virus-induced lung inflammation,which may be related to its inhibition activity on influenza virus neuraminidase and its antioxidant activities.