PDF(Pubmed)
Abstract：
BACKGROUND: Sepsis is one of the most common clinical diseases, which is characterized by a serious and uncontrollable inflammatory response. LPS-induced inflammation is a critical pathological event in sepsis, but the underlying mechanism has not yet been fully elucidated.
METHODS: The animal model was established for two batches. In the first batch of experiments, Adult C57BL/6J mice were randomly divided into control group and LPS (5 mg/kg, i.p.)group . In the second batch of experiments, mice were randomly divided into control group, LPS group, and LPS+VX765(10 mg/kg, i.p., an inhibitor of NLRP3 inflammasome) group. After 24 hours, mice were anesthetized with isoflurane, blood and intestinal tissue were collected for tissue immunohistochemistry, Western blot analysis and ELISA assays.
RESULTS: The C57BL/6J mice injected with LPS for twenty-four hours could exhibit severe inflammatory reaction including an increased IL-1β, IL-18 in serum and activation of NLRP3 inflammasome in intestine. The injection of VX765 could reverse these effects induced by LPS. These results indicated that the increased level of IL-1β and IL-18 in serum induced by LPS is related to the increased intestinal permeability and activation of NLRP3 inflammasome. In the second batch of experiments, results of western blot and immunohistochemistry showed that Slit2 and Robo4 were significant decreased in intestine of LPS group, while the expression of VEGF was significant increased. Meanwhile, the protein level of tight junction protein ZO-1, occludin, and claudin-5 were significantly lower than in control group, which could also be reversed by VX765 injection.
CONCLUSIONS: In this study, we revealed that Slit2-Robo4 signaling pathway and tight junction in intestine may be involved in LPS-induced inflammation in mice, which may account for the molecular mechanism of sepsis.
METHODS: The animal model was established for two batches. In the first batch of experiments, Adult C57BL/6J mice were randomly divided into control group and LPS (5 mg/kg, i.p.)group . In the second batch of experiments, mice were randomly divided into control group, LPS group, and LPS+VX765(10 mg/kg, i.p., an inhibitor of NLRP3 inflammasome) group. After 24 hours, mice were anesthetized with isoflurane, blood and intestinal tissue were collected for tissue immunohistochemistry, Western blot analysis and ELISA assays.
RESULTS: The C57BL/6J mice injected with LPS for twenty-four hours could exhibit severe inflammatory reaction including an increased IL-1β, IL-18 in serum and activation of NLRP3 inflammasome in intestine. The injection of VX765 could reverse these effects induced by LPS. These results indicated that the increased level of IL-1β and IL-18 in serum induced by LPS is related to the increased intestinal permeability and activation of NLRP3 inflammasome. In the second batch of experiments, results of western blot and immunohistochemistry showed that Slit2 and Robo4 were significant decreased in intestine of LPS group, while the expression of VEGF was significant increased. Meanwhile, the protein level of tight junction protein ZO-1, occludin, and claudin-5 were significantly lower than in control group, which could also be reversed by VX765 injection.
CONCLUSIONS: In this study, we revealed that Slit2-Robo4 signaling pathway and tight junction in intestine may be involved in LPS-induced inflammation in mice, which may account for the molecular mechanism of sepsis.
摘要：
背景：脓毒症是最常见的临床疾病之一，其特征是严重和无法控制的炎症反应。LPS诱导的炎症是脓毒症的关键病理事件,但是潜在的机制尚未完全阐明。
方法：建立两批动物模型。在第一批实验中，成年C57BL/6J小鼠随机分为对照组和LPS(5mg/kg,i.p.）组。在第二批实验中，将小鼠随机分为对照组,LPS组,和LPS+VX765（10mg/kg，i.p.,NLRP3炎性体抑制剂)组。24小时后,小鼠用异氟烷麻醉，收集血液和肠组织进行组织免疫组织化学，蛋白质印迹分析和ELISA测定。
结果：注射LPS24小时的C57BL/6J小鼠可表现出严重的炎症反应，包括增加的IL-1β，血清IL-18与肠道NLRP3炎性体的激活.注射VX765可以逆转LPS诱导的这些作用。这些结果表明，LPS诱导的血清中IL-1β和IL-18水平升高与肠道通透性增加和NLRP3炎性体的激活有关。在第二批实验中，Westernblot和免疫组化结果显示,LPS组大鼠肠道组织中Slit2和Robo4显著降低,而VEGF的表达明显增加。同时,紧密连接蛋白ZO-1，闭塞蛋白，claudin-5明显低于对照组,这也可以通过VX765注入逆转。
结论：在这项研究中，我们发现Slit2-Robo4信号通路和肠道紧密连接可能参与LPS诱导的小鼠炎症,这可能解释了脓毒症的分子机制。
方法：建立两批动物模型。在第一批实验中，成年C57BL/6J小鼠随机分为对照组和LPS(5mg/kg,i.p.）组。在第二批实验中，将小鼠随机分为对照组,LPS组,和LPS+VX765（10mg/kg，i.p.,NLRP3炎性体抑制剂)组。24小时后,小鼠用异氟烷麻醉，收集血液和肠组织进行组织免疫组织化学，蛋白质印迹分析和ELISA测定。
结果：注射LPS24小时的C57BL/6J小鼠可表现出严重的炎症反应，包括增加的IL-1β，血清IL-18与肠道NLRP3炎性体的激活.注射VX765可以逆转LPS诱导的这些作用。这些结果表明，LPS诱导的血清中IL-1β和IL-18水平升高与肠道通透性增加和NLRP3炎性体的激活有关。在第二批实验中，Westernblot和免疫组化结果显示,LPS组大鼠肠道组织中Slit2和Robo4显著降低,而VEGF的表达明显增加。同时,紧密连接蛋白ZO-1，闭塞蛋白，claudin-5明显低于对照组,这也可以通过VX765注入逆转。
结论：在这项研究中，我们发现Slit2-Robo4信号通路和肠道紧密连接可能参与LPS诱导的小鼠炎症,这可能解释了脓毒症的分子机制。
