牛磺酸对矽尘处理大鼠肺组织肿瘤坏死因子蛋白表达的影响

目的探讨牛磺酸对矽尘处理大鼠肺组织肿瘤坏死因子-α(TNF-α)蛋白表达的影响。方法将Wistar大鼠144只随机分为对照组、矽尘组和牛磺酸组,每组48只。采用气管暴露法给矽尘组和牛磺酸组的动物以染矽尘处理,牛磺酸组大鼠在矽尘处理前3天饲料中开始添加牛磺酸。每个实验组分为6个时间点(1、3、7、14、21和28天)分别取8只大鼠处死。高效液相色谱法测定其血浆中牛磺酸含量;链霉菌抗生物素蛋白-过氧化物酶法(SP法)结合组织芯片、图像分析技术检测矽尘处理动物的肺组织TNF-α的表达,用Image-ProPlus图像分析系统对TNF-α的表达做定量分析。结果牛磺酸组6个时间点血浆中牛磺酸浓度都明显高于对照组和矽尘组(P<0.01或P<0.05)。矽尘组TNF-α蛋白表达量第1天时开始升高,第7天时达高峰。第7和14天高出对照组6.57%和2.37%(P<0.05或P<0.01)。牛磺酸组TNF-α蛋白表达量分别于第3、7和21天低于矽尘组,第7天时低于矽尘组3.52%(P<0.05)。结论牛磺酸能够抑制矽尘诱导的大鼠肺组织TNF-α蛋白的过度表达。

Effects of taurine on tumor necrosis factor expression of lung in rats treated by silica

OBJECTIVE: To evaluate the effects of taurine on the expression of tumor necrosis factor-alpha (TNF-alpha) protein of lung in rats treated by silica. METHODS: 144 Wistar rats were randomly divided into three experimental groups: saline-instilled with a control diet (saline-treated group), silica-instilled with a control diet (silica-treated group), and silica-instilled with a diet containing 2.5% taurine (taurine-treated group). There were 48 rats in every experimental group. Rats were treated by direct tracheal instillation of silica into rat lungs exposed surgically. 8 rats in every experimental group were killed at each at 6 time points (1, 3, 7, 14, 21 and 28 day) respectively. The taurine concentration of serum were analyzed by means of HPLC. The expression of TNF-alpha protein in paraffin-embedded lung sections with Streptavidin/ peroxidase(SP) immunohistochemistry on tissue microarray were measured by image-pro Plus. RESULTS: The concentration of taurine in serum of taurine-treated group were significantly elevated when compared with saline-treated and silica-treated groups (P < 0.05, P < 0.01). After instillation of silica, TNF-alpha positive area percent of the lung was elevated in silica-treated rats when compared with the corresponding saline-treated group, peaking at 7 days, and elevated by 6.57% and 2.37% at 7 days and 14 days respectively (P < 0.01 or P < 0.05). Taurine treatment significantly decreased silica-elevated TNF-alpha positive area percent by 3.52 at 7 day (P < 0.05). CONCLUSION: Treatment with taurine can effectively attenuate the pathological expression of TNF-alpha protein of lung in rats induced by silica.