Touré Fatouma, Zahm Jean-Marie, Garnotel Roselyne, Lambert Elise, Bonnet Noel, Schmidt Ann Marie, Vitry Fabien, Chanard Jacques, Gillery Philippe, Rieu Philippe
Laboratory of Biochemistry and Molecular Biology, CNRS UMR 6198, F-51095 Reims, France.
Biochem J. 2008 Dec 1;416(2):255-61. doi: 10.1042/BJ20080054.
AGEs (advanced glycation end-products) accumulate in collagen molecules during uraemia and diabetes, two diseases associated with high susceptibility to bacterial infection. Because neutrophils bind to collagen during their locomotion in extravascular tissue towards the infected area we investigated whether glycoxidation of collagen (AGE-collagen) alters neutrophil migration. Type I collagen extracted from rat tail tendons was used for in vitro glycoxidation (AGE-collagen). Neutrophils were obtained from peripheral blood of healthy adult volunteers and were used for the in vitro study of adhesion and migration on AGE- or control collagen. Glycoxidation of collagen increased adhesion of neutrophils to collagen surfaces. Neutrophil adhesion to AGE-collagen was inhibited by a rabbit anti-RAGE (receptor for AGEs) antibody and by PI3K (phosphoinositide 3-kinase) inhibitors. No effect was observed with ERK (extracellular-signal-regulated kinase) or p38 MAPK (mitogen-activated protein kinase) inhibitors. AGE-collagen was able to: (i) induce PI3K activation in neutrophils, and (ii) inhibit chemotaxis and chemokinesis of chemoattractant-stimulated neutrophils. Finally, we found that blocking RAGE with anti-RAGE antibodies or inhibiting PI3K with PI3K inhibitors restored fMLP (N-formylmethionyl-leucyl-phenylalanine)-induced neutrophil migration on AGE-collagen. These results show that RAGE and PI3K modulate adhesion and migration rate of neutrophils on AGE-collagen. Modulation of adhesiveness may account for the change in neutrophil migration rate on AGE-collagen. As neutrophils rely on their ability to move to perform their function as the first line of defence against bacterial invasion, glycoxidation of collagen may participate in the suppression of normal host defence in patients with diabetes and uraemia.
晚期糖基化终末产物（AGEs）在尿毒症和糖尿病期间会在胶原蛋白分子中蓄积，这两种疾病都与细菌感染的高易感性相关。由于中性粒细胞在血管外组织中向感染区域移动时会与胶原蛋白结合，我们研究了胶原蛋白的糖氧化（AGE-胶原蛋白）是否会改变中性粒细胞的迁移。从大鼠尾腱中提取的I型胶原蛋白用于体外糖氧化（AGE-胶原蛋白）。中性粒细胞取自健康成年志愿者的外周血，用于体外研究其在AGE-胶原蛋白或对照胶原蛋白上的黏附和迁移。胶原蛋白的糖氧化增加了中性粒细胞与胶原蛋白表面的黏附。抗RAGE（AGEs受体）兔抗体和PI3K（磷脂酰肌醇3-激酶）抑制剂可抑制中性粒细胞与AGE-胶原蛋白的黏附。细胞外信号调节激酶（ERK）或p38丝裂原活化蛋白激酶（MAPK）抑制剂未观察到效果。AGE-胶原蛋白能够：（i）诱导中性粒细胞中的PI3K活化，以及（ii）抑制趋化因子刺激的中性粒细胞的趋化作用和化学运动。最后，我们发现用抗RAGE抗体阻断RAGE或用PI3K抑制剂抑制PI3K可恢复N-甲酰甲硫氨酰-亮氨酰-苯丙氨酸（fMLP）诱导的中性粒细胞在AGE-胶原蛋白上的迁移。这些结果表明，RAGE和PI3K调节中性粒细胞在AGE-胶原蛋白上的黏附和迁移速率。黏附性的调节可能解释了中性粒细胞在AGE-胶原蛋白上迁移速率的变化。由于中性粒细胞依靠其移动能力作为抵御细菌入侵的第一道防线来发挥功能，胶原蛋白的糖氧化可能参与了糖尿病和尿毒症患者正常宿主防御的抑制。
