Department of Clinical and Experimental Medicine and Pharmacology, School of Medicine, University of Messina, 98100 Messina, Italy.
J Leukoc Biol. 2010 Feb;87(2):309-21. doi: 10.1189/jlb.0609438. Epub 2009 Dec 22.
LXR is another member of the superfamily of nuclear hormone receptors that heterodimerizes with RXR and regulates the intracellular levels of cholesterol through gene induction of enzymes and proteins involved in the cholesterol metabolism and transport. LXR ligands inhibit the gene expression of proinflammatory mediators in immunostimulated macrophages; in vivo studies have shown that activation of LXR reduces the inflammatory response in a murine model of contact dermatitis and atherosclerosis. No reports have addressed a role for LXRs in pathophysiology of intestinal ischemia. The aim of this study was to investigate the effects of T0901317, a potent LXR ligand, in a mouse model of SAO shock, which was induced by clamping the superior mesenteric artery and the celiac trunk, resulting in a total occlusion of these arteries for 30 min. After this period of occlusion, the clamps were removed. Mice were killed at 60 min after reperfusion. This study provides the evidence that T0901317, LXR agonist, modulates: the development of SAO shock; the infiltration of the tissue with PMNs; the expression of TNF-alpha and IL-1beta; the nitration of tyrosine residues; NF-kappaB expression; the MAPK phosphorylation (ERK, JNK, and p38); FasL; apoptosis; Bax and Bcl-2 expression; and the degree of tissue injury caused by SAO shock. Our results imply that LXR agonists may be useful in the therapy of inflammation.
LXR 是核激素受体超家族的另一个成员,它与 RXR 形成异二聚体,通过诱导参与胆固醇代谢和转运的酶和蛋白,调节细胞内胆固醇水平。LXR 配体抑制免疫刺激的巨噬细胞中促炎介质的基因表达;体内研究表明,LXR 的激活可降低接触性皮炎和动脉粥样硬化的小鼠模型中的炎症反应。目前尚无报道涉及 LXR 在肠缺血病理生理学中的作用。本研究旨在探讨 T0901317(一种有效的 LXR 配体)在由夹闭肠系膜上动脉和腹腔干引起的 SAO 休克小鼠模型中的作用,导致这些动脉完全闭塞 30 分钟。在这段闭塞期后,松开夹子。再灌注 60 分钟后处死小鼠。本研究提供的证据表明,LXR 激动剂 T0901317 可调节:SAO 休克的发展;PMN 浸润组织;TNF-α和 IL-1β的表达;酪氨酸残基的硝化;NF-κB 表达;MAPK 磷酸化(ERK、JNK 和 p38);FasL;细胞凋亡;Bax 和 Bcl-2 表达;以及由 SAO 休克引起的组织损伤程度。我们的结果表明,LXR 激动剂可能对炎症的治疗有用。