RvE1, a lipid mediator derived from Eimsapentaenoic add regulates intestinal inflammation in experimental colitis

背景/目标;富含鱼油的ω-3多不饱和脂肪酸（PUFA）如二十碳五烯酸（EPA）和二十二碳六烯酸（DHA）被认为对多种人类炎症性疾病（包括炎症性肠病（IBD））有益，但其分子机制尚不清楚。最近，Resolvin E1（RvE 1），一种由EPA诱导的内源性脂质介质被鉴定为在愈合阶段由酶如环氧化酶-2和5-脂氧合酶在局部炎症中产生。RvE 1在体内可抑制小鼠脾树突状细胞的迁移，在体外可抑制弓形虫速殖子抗原提取物刺激小鼠脾树突状细胞产生IL-12。此外，我们已经报道了RvE 1对TNBS诱导的小鼠结肠炎的保护作用，这是已知的Th 1-显性急性结肠炎模型。然而，仍有待观察哪些免疫细胞表达RvE 1受体（ChemR 23）， ...更多信息 目前已详细鉴定，并对结肠炎症的调节机制进行了研究。方法/结果：用单克隆抗体检测小鼠体内表达ChemR 23的细胞。ChemR 23主要表达于小鼠腹腔巨噬细胞。因此，用RvE 1预处理腹腔巨噬细胞，随后用LPS刺激，然后通过真实的时间RT-PCR分析促炎细胞因子的mRNA。用RvEl处理导致IL-12 p40、TNF-α以及另外的IL-10、TGF-β的抑制。接下来，由于已知NFKb在细胞因子调节中起作用，我们评估了刺激后用RvE 1预处理是否可以抑制NFKb的核转位。为此，用TNF-α刺激具有ChemR 23的HEK 293转染子细胞或用RvEl或对照预处理的模拟细胞，然后用抗NF-kBp 65抗体染色。RvE 1预处理通过ChemR 23的依赖性方式抑制TNF-α诱导的NF-κ B核转位。这些结果表明，RvE 1可以调节表达ChemR 23的巨噬细胞的免疫应答。因此，我们研究了RvE 1在葡聚糖硫酸钠（DSS）诱导的结肠炎中的有益作用，其不依赖于T细胞和B细胞。在8周龄的C57 BL 16或Ragl缺陷的雌性小鼠中施用3.5%DSS诱导了严重的结肠炎。然而，RvE 1治疗导致保护DSS结肠炎的临床表现和组织学评分。结论：RvE 1不仅对Th 1型疾病有效，而且对巨噬细胞诱导的炎症反应也有抑制作用。提示RvE 1有可能成为包括人类炎症性肠病在内的多种慢性炎症性疾病的新的治疗药物之一。少

Backgland/Aims; Omega-3 polyunsaturated fatty acids (PUFA) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are enriched in fish oils, are held to be beneficial in a wide range of human inflammatory disorders, including inflammatory bowel disease (IBD), but the molecular mechanism was unknown. Recently, Resolvin E1 (RvE1), an endogenous lipid mediator induced from EPA was identified when generated in local inflammation at the healing stage by the enzymes such as cycloocygenase-2 and 5-lipoxygenase. It was reported that RvE1 inhibited the migration of dendritic cells in the spleen in vivo and the production of 1L-12 in vitro after the stimulation with the pathogen extracts derived from Toxoplasma gondii soluble tachyzoite antigen. In addition, we have reported that RvE1 protected against TNBS-induced colitis in mice which was known to Th1-dominant acute colitis model. However it remains to be seen which immune cells expressed RvE1 receptor (ChemR23) which was re … More cently identified in detail and the mechanism to regulate the colonic inflammation. Methods/Results; The cells expressing ChemR23 in mice was investigated using the monoclonal antibody. ChemR23 expressed mostly in mouse intraperitoneal macrophage. Therefore, intraperitoneal macrophages were pretreated with RvE1, followed by stimulation with LPS and then, mRNA of the proinflammatory cytokines were analyzed by real time RT-PCR. The treatment with RvE1 led to the inhibition of IL-12p40, TNF-a, additionally IL-10, TGF-β. Next, since it is known that NFKb plays a role in cytokine regulation, we assessed whether nuclear translocation of NFKb could be inhibited by the pretreatment with RvE1 after the stimulation. To do so, HEK 293 transfectant cells with ChemR23 or mock cells which were pretreated with RvEl or control were stimulated with TNF-α and then, stained with anti-NF-kBp65 antibody. RvE1 pretreatment inhibits TNF-α-induced nuclear translocation of NF-kB by the dependent manner of ChemR23. These results suggested that RvE1 could regulate immune response on macrophage expressing ChemR23. Therefore, we investigated the beneficial effect of RvE1 in dextran sulfate sodium (DSS) induced colitis which was independent with T cells and B cells. The administration of 3.5%DSS in 8weeks-old C57BL16 or Ragl-deficient female mice was induced severe colitis. RvE1 treatment, however, led to protect DSS colitis about clinical findings and histological score. Conclusion: These data suggest that RvE1 was effective for Th1-dominant disease, but also the suppression of macrophage induced inflammation. Therefore these data suggested that RvE1 may be one of new treatment of many kinds of chronic inflammatory disease including human inflammatory bowel disease. Less