Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT 06510-3221, USA.
Department of Basic, Preventive and Clinical Science, University of Transylvania, 500019 Brasov, Romania.
Science. 2018 Aug 10;361(6402):599-603. doi: 10.1126/science.aap9331.
Excess dietary lipid uptake causes obesity, a major global health problem. Enterocyte-absorbed lipids are packaged into chylomicrons, which enter the bloodstream through intestinal lymphatic vessels called lacteals. Here, we show that preventing lacteal chylomicron uptake by inducible endothelial genetic deletion of () and (; also known as ) renders mice resistant to diet-induced obesity. Absence of NRP1 and FLT1 receptors increased VEGF-A bioavailability and signaling through VEGFR2, inducing lacteal junction zippering and chylomicron malabsorption. Restoring permeable lacteal junctions by VEGFR2 and vascular endothelial (VE)-cadherin signaling inhibition rescued chylomicron transport in the mutant mice. Zippering of lacteal junctions by disassembly of cytoskeletal VE-cadherin anchors prevented chylomicron uptake in wild-type mice. These data suggest that lacteal junctions may be targets for preventing dietary fat uptake.
过量的膳食脂质摄取会导致肥胖,这是一个全球性的主要健康问题。肠上皮细胞吸收的脂质被包裹在乳糜微粒中,乳糜微粒通过称为乳糜管的肠道淋巴血管进入血液。在这里,我们表明,通过诱导性内皮细胞基因缺失()和(;也称为)来阻止乳糜管摄取,可以使小鼠抵抗饮食诱导的肥胖。NRP1 和 FLT1 受体的缺失增加了 VEGF-A 的生物利用度和通过 VEGFR2 的信号转导,诱导乳糜管连接的拉链和乳糜微粒的吸收不良。通过 VEGFR2 和血管内皮 (VE)-钙黏蛋白信号抑制恢复通透性乳糜管连接,挽救了突变小鼠中的乳糜微粒转运。通过细胞骨架 VE-钙黏蛋白锚的解组装来破坏乳糜管连接,防止了野生型小鼠中乳糜微粒的摄取。这些数据表明,乳糜管连接可能是防止膳食脂肪摄取的靶点。