NF-κB及自噬在盲肠结扎穿孔诱导脓毒症脑病大鼠海马凋亡中的作用

Effects of NF-kB and autophagy in hippocampal apoptosis induced by cecalligation and puncture in rats with septic encephalopathy

目的:探讨NF-kB及自噬在盲肠结扎穿孔诱导的脓毒症脑病大鼠海马凋亡中的作用。方法:取6周SPF级雄性SD大鼠40只,用盲肠结扎穿孔法建立脓毒症脑病大鼠模型,分别采用NF-kB阻断剂PDTC及自噬阻断剂3-MA进行干预,将大鼠分为5组:A组(对照组)、B组(模型组)、C组(模型+3-MA干预组)、D组(模型+PDTC干预组)、E组(模型+3-MA+PDTC干预组),每组8只。造模后24 h处死大鼠,用ELISA测定血清与脑组织中S100β的表达,采用免疫组化检测海马组织中凋亡相关蛋白Bcl-2、caspase-3的表达,Western blot法检测海马组织中BAX、Beclin-1的表达,凝胶迁移实验(EMSA)法检测海马组织中NFkB的活性。结果:与A组比较,B组血清与脑组织中S100β表达增多(P<0.05),海马组织中NF-kB、Beclin-1和caspase-3的表达显著增多(P<0.05),而Bcl-2的表达显著减少(P<0.05),B组、C组、D组、E组BAX表达显著升高(P<0.05)。与B组比较,C组、D组、E组血清与脑组织中S100β的表达均减少(P<0.05),海马组织中NF-kB、Beclin-1和BAX的表达显著减少(P<0.05),Bcl-2的表达显著增加;与C组比较,D组、E组NF-kB表达明显下降(P<0.05);与D组比较,E组NF-kB的表达明显下降(P<0.05)。结论:抑制NF-kB和自噬均可以减轻脓毒症脑病大鼠海马的凋亡,但对脓毒症脑病海马细胞的凋亡并不产生协同作用。

Objective:To explore the role of NF-kB and autophagy in hippocampal apoptosis induced by cecal ligation and puncture in rats with septic encephalopathy.Methods:A total of 406-week-old SPF grade male SD rats were selected to establish septic encephalopathy model by cecal ligation and puncture.The rats were intervened with NF-kB blocker PDTC and autophagy blocker 3-MA,respectively.The rats were divided into 5 groups:group A(control group),group B(model group),group C(model+3-MA intervention group),group D(model+PDTC intervention group),and group E(model+3-MA+PDTC intervention group),with 8 rats in each group.24 hours after the establishment of the model,the rats were euthanized,and the expression of S100βin serum and brain tissue were determined by ELISA.The expression of apoptosis-related proteins Bcl-2 and caspase-3 in hippocampal tissue were detected by immunohistochemistry.The expression of BAX and Beclin-1 in hippocampal tissue were detected by Western blot,and the activity of NF-kB in hippocampal tissue was detected by EMSA.Results:Compared with group A,in B group,the expression of S100βin serum and brain tissue were increased(P<0.05),the expression of NF-kB,Beclin-1 and caspase-3 in hippocampus were increased significantly(P<0.05),while the expression of Bcl-2 was decreased significantly(P<0.05),the expression of BAX in group B,C group,D group and E group were increased significantly(P<0.05).Compared with group B,in group C,group D and group E,the expression of S100βin serum and brain tissue were decreased significantly(P<0.05),the expression of NF-kB,Beclin-1 and BAX in hippocampal tissue were decreased significantly(P<0.05),while the expression of Bcl-2 was increased significantly.Compared with group C,in group D and group E,the expression of NF-kB were decreased significantly(P<0.05).Compared with group D,and the expression of NF-kB in group E was significantly decreased(P<0.05).Conclusion:Inhibition of NF-kB and autophagy can reduce hippocampal apoptosis in rats with septic encephalopathy,but have no synergistic effect on hippocampal cell apoptosis in septic encephalopathy.