目的 探讨Sestrin2（Sesn2）的保护线粒体功能在减轻脓毒症脑损伤（SAE）小鼠的认知功能障碍中的作用研究。 方法 120只6周大的雄性C57BL/6J小鼠随机分为3组，每组40只：假手术（Sham）组、CLP组、CLP + Eupatilin组。建立由盲肠结扎和穿孔（CLP）手术诱导脓毒症模型。CLP + Eupatilin组小鼠采用Eupatilin治疗。通过神经行为测试、Morris水迷宫（MWM）来确定小鼠神经行为、空间学习和记忆功能。通过尼氏染色法计数海马CA1区的神经元数目。将HT22细胞随机分为对照组（Con）、脂多糖组（LPS）、LPS + Eupatilin组、LPS + Eupatilin + si-Nrf2组。通过TUNEL染色分析细胞凋亡，和线粒体膜电位（MMP）分析线粒体损伤。 结果 在CLP手术后7 d，与Sham小鼠相比，CLP小鼠的海马和皮质中Sesn2显著下调（P < 0.01）。与CLP组相比，CLP + Eupatilin 组的存活率显著增加（P < 0.05）。与Sham组相比，CLP组小鼠表现出相对较高的神经损伤评分（P < 0.05），和具有更少的平台穿越次数和更短的目标停留时间，而CLP + Eupatilin组中小鼠神经损伤评分较CLP组显著降低（P < 0.05），并且停留在目标区域时间和平台穿越次数显著高于CLP组（P < 0.05）。与Sham组相比，CLP组小鼠海马组织中神经元、Sesn2和Nrf2的共定位率明显减少（P < 0.05），和CD68/Iba-1阳性小胶质细胞数量显著增加（P < 0.05），而CLP + Eupatilin组逆转了这些变化。与Con组相比，LPS组细胞凋亡和MMP水平显著增加（P < 0.01），而LPS + Eupatilin组细胞凋亡和MMP水平显著低于LPS组（P < 0.05）。然而，Nrf2敲低（LPS + Eupatilin + si-Nrf2组）逆转了Eupatilin的抗细胞凋亡作用和线粒体保护作用。 结论 Eupatilin通过激活Sesn2-Nrf2通路减轻SAE小鼠的认知功能障碍、神经功能缺损，并且通过减轻线粒体功能障碍来改善炎症微环境。

Objective To explore the role of protective function of Sestrin2 （Sesn2） to mitochondria in alleviating cognitive dysfunction in mice with sepsis-associated encephalopathy （SAE）. Methods 6-week-old male C57BL/6J mice were randomly divided into three groups： sham group， CLP group and CLP plus eupatilin group， 40 mice in each group. A sepsis model was induced by cecal ligation and perforation （CLP）. The CLP plus eupatilin group was treated with eupatilin. Neurobehavioral test and Morris water maze （MWM） were used to determine neurobehavior and spatial learning and memory function in mice. The number of neurons in hippocampal CA1 area was counted by Nissl staining. HT22 cells were randomly divided into a control group （Con）， lipopolysaccharide group （LPS）， LPS plus eupatilin treatment group （LPS plus eupatilin） and LPS plus eupatilin and Nrf2 siRNA treatment group （LPS plus eupatilin and si-Nrf2）. Apoptosis was analyzed by terminal deoxynucleotidyl transferase-mediated nick end labeling （TUNEL） staining， Mitochondrial membrane potential （MMP） was used to analyze mitochondrial damage. Results Seven days after CLP， as compared with sham mice， Sesn2 in hippocampus and cortex decreased significantly in CLP mice （P < 0.01）. As compared with CLP group， the survival rate in CLP plus eupatilin group increased significantly （P < 0.05）. As compared with sham group， the mice in CLP group showed a relatively high nerve injury score （P < 0.05）， and had fewer platform crossings and shorter target stay time， while the mice in CLP plus eupatilin group exhibited a lower injury score （P < 0.05）， and stayed in the target area for a longer time （P < 0.05）. As compared with sham group， the co-localization rate of neurons， Sesn2 and Nrf2 in CLP group decreased significantly （P < 0.05）， and the number of CD68/Iba-1 positive microglia increased significantly （P < 0.05）， while CLP plus eupatilin group reversed these changes. As compared with Con group， apoptosis and MMP level in LPS group increased significantly （P < 0.01）， while apoptosis and MMP level in LPS plus eupatilin group were lower than those in LPS group （P < 0.05）. However， Nrf2 knockdown （LPS plus eupatilin and si-Nrf2 group） reversed the anti-apoptosis and mitochondrial protection of eupatilin. Conclusions Eupatilin can alleviate cognitive dysfunction and neurological deficit in SAE mice by activating Sesn2-Nrf2 pathway， and improve inflammatory microenvironment by alleviating mitochondrial dysfunction.