CHYLOMICRONS CAN INHIBIT ENDOTOXIN ACTIVITY INVITRO
CHYLOMICRONS CAN INHIBIT ENDOTOXIN ACTIVITY INVITRO
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DOI：
10.1016/0022-4804(91)90143-a
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发表时间：
1991-11-01
影响因子：
2.2
通讯作者：
RAPP, JH
中科院分区：
文献类型：
--
作者：
EICHBAUM, EB;HARRIS, HW;RAPP, JH
创伤、热损伤和非致死剂量的内毒素可促进内毒素穿过结肠粘膜屏障进入肠系膜淋巴管和体循环。细菌内毒素血症会引起脂质代谢的变化，包括循环中富含甘油三酯的脂蛋白的增加。由于富含胆固醇的脂蛋白可以在体外和体内中和内毒素的毒性活性，因此我们询问富含甘油三酯的乳糜微粒是否可以抑制体外内毒素活性（通过显色鲎试验测定）。我们测试了完整乳糜微粒与热变性乳糜微粒对增加浓度的大肠杆菌 (055:B5) 内毒素体外活性的影响。与变性的乳糜微粒相比，完整的乳糜微粒可抑制高达 1 μg 内毒素/mg 乳糜微粒甘油三酯的检测量高达 12 倍（P < 0.001）。这项研究表明，乳糜微粒是体外内毒素活性的有效抑制剂。由于来自结肠的易位内毒素与肠系膜淋巴管中肠源性乳糜微粒相关，这可能代表了针对肠道来源内毒素血症的天然防御机制。
Trauma, thermal injury, and nonlethal doses of endotoxin can promote the translocation of endotoxin across the mucosal barrier of the colon into the mesenteric lymphatics and systemic circulation. Bacterial endotoxemia induces changes in lipid metabolism, including an increase in circulating triglyceride-rich lipoproteins. Because cholesterol-rich lipoproteins can neutralize the toxic activity of endotoxin, bothin vitroandin vivo, we asked whether triglyceride-rich chylomicrons can inhibit endotoxin activityin vitroas measured by a chromogenic Limulus assay. We tested the effect of intact versus heat-denatured chylomicrons on thein vitroactivity of increasing concentrations ofEscherichia coli(055:B5) endotoxin. Intact chylomicrons inhibited up to 12-fold the detection of as much as 1 μg of endotoxin/mg of chylomicron triglyceride, compared to denatured chylomicrons (P< 0.001). This study shows that chylomicrons are potent inhibitors of endotoxin activityin vitro. Because translocated endotoxin from the colon associates with gut-derived chylomicrons in the mesenteric lymphatics, this may represent a natural defensive mechanism against endotoxemia of enteric origin.