植物甾醇对脂多糖诱导小鼠炎症的抑制作用 Inhibition of phytosterols on lipopolysaccharide-induced inflammation in mice

以预饲喂植物甾醇的小鼠为研究对象，采用脂多糖诱导小鼠产生炎症，研究不同剂量的植物甾醇对炎症发生的预防效果。结果表明：与脂多糖组相比，植物甾醇组小鼠血清中炎症因子白介素1β（IL-1β）、白介素6（IL-6）和肿瘤坏死因子α（TNF-α）含量显著（P<0.05）或极显著（P<0.01）降低，肝脏和脾脏炎症病变损伤明显改善，植物甾醇组小鼠肝脏、脾脏中一氧化氮合酶（iNOS）的分泌显著（P<0.05）或极显著（P<0.01）减少；在蛋白水平上，核转录因子κB（NF-κB）p65蛋白的表达及其磷酸化蛋白水平显著（P<0.05）或极显著（P<0.01）降低；与脂多糖组相比，预饲喂植物甾醇的小鼠发生炎症后，其肝脏、脾脏中蛋白酪氨酸磷酸酶1（SHP-1）极显著升高（P<0.01）。据此推测负调控因子SHP-1表达上调后，抑制了NF-κB激活，进而降低iNOS表达水平，抑制下游炎症因子IL-1β、IL-6和TNF-α的生成，起到了降低炎症对机体器官损害的作用。因此，植物甾醇在降低小鼠机体炎症方面有显著效果，在预防养殖动物感染方面具有重要意义。Taking mice prefed with phytosterols as the research object, lipopolysaccharide was used to induce inflammation in mice, and the preventive effects of different dosages of phytosterols on inflammation were studied. The results showed that compared with lipopolysaccharide group, inflammatory factors interleukin-1β（IL-1β）, interleukin-6 (IL-6) and tumor necrosis factor α（TNF- α）in serum of mice in phytosterol group decreased significantly (P<0.05) or extremely significantly (P<0.01). The inflammatory lesions of liver and spleen were significantly improved. The secretion of nitric oxide synthase (iNOS) in liver and spleen of mice in phytosterol groups decreased significantly (P<0.05) or extremely significantly (P<0.01). At the protein level, the expressions of nuclear transcription factor κB（NF- κB) p65 protein and its phosphorylated protein decreased significantly(P<0.05) or extremely significantly (P<0.01). At the same time, compared with the lipopolysaccharide group, the protein tyrosine phosphatase-1 (SHP-1) in liver and spleen of mice prefed with phytosterols increased extremely significantly (P<0.01) after inflammation. It was speculated that after the expression of negative regulator SHP-1 was up-regulated, NF-κB activation was inhibited, which reduced the expression level of iNOS and inhibited the downstream inflammatory factors IL-1β、 IL-6 and TNF- α, playing a role in reducing the invasion of inflammation to body organs. Therefore, phytosterols have a significant effect in reducing inflammation in mice and are of great significance in preventing infection in cultured animals.