Identification of inflammation-mediated oxidized cholesterols as novel biomarkers of the metabolic syndrome

代谢综合征是动脉粥样硬化的危险因素。脂肪细胞产生的脂肪细胞因子可以激活各种炎症细胞产生活性氧和活性氮，在宿主防御病原体和炎症组织损伤中发挥重要作用。最近有报道称，人体活化的中性粒细胞在体内产生一种类似臭氧的氧化剂，但也报道了相互矛盾的实验结果。在本研究中，为了确定人体炎症细胞是否在体内产生臭氧样氧化剂，我们利用与臭氧反应特异性产生的氧化胆固醇-动脉粥样硬化- a和B进行了以下研究：(1)动脉粥样硬化- a和B的合成和表征；(2)利用荧光丹酰肼衍生物建立了一种高灵敏度和特异性的检测动脉粥样硬化- a和B的方法；(3)阐明了炎症细胞体内形成动脉粥样硬化- a和B的机制；(4)生物活性，特别是诱导凋亡细胞死亡的能力；(5)糖尿病大鼠肝脏等组织中动脉粥样硬化- a、B的检测。该方法的灵敏度比以往报道的方法高1000倍左右，可以很容易地检测到化合物的fmol水平。使用这种方法，我们已经表明，与未被活化的人中性粒细胞样（HL-60）细胞相比，被磷酯活化的人中性粒细胞样（HL-60）细胞中形成的动脉粥样硬化- b水平增加。由于一种抑制臭氧介导氧化的化合物特异性地抑制了动脉粥样硬化- b的形成，我们的数据强烈表明，活化的HL-60产生的臭氧参与了动脉粥样硬化的形成。研究还表明，动脉粥样硬化具有很强的细胞毒性。由于我们还检测到糖尿病大鼠肝脏中动脉粥样硬化水平升高，因此这些化合物可以作为代谢综合征的新标志物进行测量。少

The metabolic syndrome is a risk factor for atherosclerosis. Adipocytokines produced by fat cells may activate various inflammatory cells to produce reactive oxygen and nitrogen species, which play important roles in host defenses against pathogens as well as in tissue damage in inflamed tissues. It has recently been reported that human activated neutrophils produce an ozone-like oxidant (s) in vivo, but conflicting experimental results have also been reported. In the present study in order to establish whether human inflammatory cells produce the ozone-like oxidant in vivo, we have investigated the followings using atheronal-A and B, which are oxidized-cholesterols specifically produced by the reaction with ozone: (1) synthesis and characterization of atheronal-A and B, (2) development of a highly sensitive and specific method to detect atheronal-A and B using fluorescent dansyl hydrazine derivatives, (3) elucidation of the mechanism for the formation of atheronal-A and B and also ozo … More ne-like oxidant (s) in vivo by inflammatory cells, (4) biological activities, especially ability to induce apoptotic cell death, and(5)detection of atheronal-A and B in tissues such as the liver of diabetes rats. Our developed method is about one thousand times more sensitive than the previously reported methods and can detect fmol levels of the compounds easily. Using this method, we have shown that increased levels of atheronal-B were formed in human neutrophil-like (HL-60) cells activated with phorbolester, compared to those without activation. As the formation of atheronal-B was inhibited specifically by a compound which inhibits ozone-mediated oxidation, our data strongly suggest that ozone produced by the activated HL-60 is involved in the formation of atheronals. It was also shown that atheronals exhibited strong cytotoxicity. As we also detected elevated levels of atheronals in the liver of diabetes rats, the compounds could be measured as a novel marker for the metabolic syndrome. Less