抗氧化剂SS-31肽对脓毒症小鼠海马神经元凋亡与炎症反应的影响

Effects of Antioxidant SS-31 Peptide on Hippocampal Apoptosis and Inflammatory Response in the Mice with Sepsis

目的:观察抗氧化剂SS-31肽对脓毒症小鼠海马神经元凋亡与炎症反应的影响。方法:成年雄性C57BL/6小鼠65只随机分为3组:假手术组(Sham组,15只)、脓毒症组(CLP组,25只)和脓毒症+SS-31肽组(SS-31肽组,25只)。CLP组和SS-31肽组建立盲肠结扎穿孔模型。术毕SS-31肽组腹腔注射SS-31肽(5 mg·kg-1),Sham组和CLP组注射等容生理盐水,连续单次注射6天。记录术后7天内死亡率;随后处死小鼠取海马组织,检测线粒体活性氧自由基(ROS)水平,Western bloting检测总细胞色素C(Cyt C)、细胞质Cyt C、caspase 3和Nlrp 3含量;酶联免疫吸附法(ELISA)检测白细胞介素1β(IL-1β)和神经元特异性烯醇化酶(NSE)水平。结果:与CLP组相比,SS-31肽组7天死亡率明显降低(52%vs 24%),线粒体ROS水平、细胞质Cyt C、caspase 3和Nlrp 3含量以及IL-1β、NSE水平均减少(P<0.05)。结论:抗氧化剂SS-31肽可降低脓毒症小鼠脑海马组织中线粒体ROS水平,抑制凋亡和炎症反应,改善损伤,降低死亡率。

Objective： To observe the effects of antioxidant SS-31 on hippocampal apoptosis and in-flammatory response in the mice with sepsis. Methods： Sixty five C57BL/6 male mice were randomly di-vided into 3 groups： sham operation group （Sham group, n=15）, CLP group （CLP group, n=25）, and CLP＋SS-31 peptide group （SS-31 peptide group, n=25）. The model of sepsis was established by cecal ligation and puncture （CLP） in the mice of CLP and SS-31 peptide groups. Mice received an administration of SS-31 peptide （5 mg＆#183;kg-1） immediately and once daily for 6 consecutive days after the operation in the SS-31 peptide group or equal volume of saline in the Sham and CLP groups. At the 7th day, mortality was recorded. After that, the mice were sacrificed to obtain the hippocampus. Reactive oxygen species （ROS） assay kit was used to detect the level of mitochondrial ROS; Western blotting was used to detect the con-tents of total and cytosolic cytochrome C （Cyt C）, caspase 3 and Nlrp 3; and enzyme linked immunosorbent assay （ELISA） was used to quantify the levels of interleukin-1β （IL-1β） and neuron specific enolase （NSE）. Results： Compared with the CLP group, the mortality of mice was reduced from 52% to 24%, and the hippocampal levels of mitochondrial ROS, cytosolic Cyt C, caspase 3, Nlrp 3, IL-1β and NSE were all de-creased in the SS-31 peptide group （P〈0.05）. Conclusion： SS-31 peptide can reduce the hippocampal mi-tochondrial ROS generation, inhibit the hippocampal neuronal apoptosis and inflammatory response, amelio-rate the injury and improve the mortality of mice with sepsis.