牛磺酸对重症急性胰腺炎大鼠枯否细胞p38MAPK信号转导通路的影响

Effects of taurine on p38 mitogen-activated protein kinase signaling pathway in Kupffer cells from severe acute pancreatitis rats

目的探讨牛磺酸对重症急性胰腺炎(severe acute pancreatitis,SAP)大鼠枯否细胞(KCs)P38MAPK的影响以及对分泌促炎细胞因子TNF-α和IL-1β的作用。方法48只SD大鼠采用完全随机法分为假手术对照(SO)组、SAP组、SAP+Taur(牛磺酸)组。SAP模型通过胰胆管逆行注射5%牛磺胆酸钠诱导,造模前SAP+Taur组分别于24、12h从尾静脉内注入牛磺酸(3mmol/L,0.1ml/100g)。假手术或造模后分别于12、24h处死动物,检测其血清中AST、ALT、AMS含量;分离KCs,采用Western blot法检测P38MAPK活化情况,凝胶电泳迁移率法(EMSA)检测KCs中NF-κB DNA的表达,并用ELISA法检测KCs培养上清液中TNF-α和IL-1β蛋白含量。结果SAP组大鼠血清中AST、ALT、AMS含量均较SO组明显升高(P<0.01);而SAP+Taur组血清中AST、ALT、AMS含量与SAP组比较,明显降低(P<0.05)。SAP组各时间点大鼠KCs中p38MAPK活性显著高于SO组(P<0.01),而且NF-κB的表达也明显高于SO组(P<0.01),KCs培养上清液中TNF-α和IL-1β蛋白含量明显高于SO组(P<0.01),但SAP+Taur组大鼠KCs上述指标均显著低于SAP组。结论牛磺酸可以抑制急性胰腺炎时KCs中p38MAPK的活化,减少NF-κB的表达,从而对促炎细胞因子TNF-α和IL-1β的分泌起抑制作用,可能具有临床应用前景。

Objective To investigate the effects of taurine on p38 mitogen-activated protein kinase （p38MAPK） signaling pathway and pro-inflammatory cytokines, tumor necrosis factor-α （TNF-α） and inter-leukin-1β （IL-1β） in Kupffer cells （KCs） from severe acute pancreatitis （SAP） rats. Methods Sprague- Dawley rats were randomized into three groups： ① sham operation group （SO）, ② SAP group, ③ SAP plus taurine group （SAP ＋ Taur）. The SAP model was created by retrogressive injection of 5% sodium taurocholate solution through the bili-pancreatic duct. Rats in SAP ＋ taurine group were injected with taurine （3 mmol/L, 0.1 ml/100 g） through the vena caudalis at 12 and 24 h before the establishment of SAP model. Rats from each group were sacrificed at 12 and 24 h after sham operation or SAP treatment. The levels of serum transaminase and amylase were detected. Then KCs in each group were isolated. The activities of p38 MAPK and NF-κB DNA in KCs were detected by Western blotting and electrophoretic mobility assay respectively. The levels of TNF-α and IL-1β in the supernatant were determined by ELISA. Results In SAP group, the levels of serum transaminase and amylase were significantly higher than those in SO group （P 〈 0. 01 ） , but in SAP ＋ Taur group, they were significantly lower than those in SAP group （P 〈 0. 05）. The activities of p38 MAPK and NF-κB in KCs in SAP rats were significantly higher than those in sham operation rats （P 〈0.01 ）. SAP could also enhance the protein expressions of TNF-α and IL-1β in the supernatant （P 〈 0. 01 ）. These events were significantly inhibited by treatment with taurine. Conclusion The inhibited activation of p38MAPK and the down-regulated expression of NF-κB may contribute the inhibitory effect of taurine on the secretion of pro-inflammatory cytokines, TNF-α and IL-1β. Therefore, taurine may be of potential clinical application for the prevention and treatment of SAP.