Lv Sa, Wei Lai, Wang Jiang-hua, Wang Jing-yan, Liu Feng
Peking University People's Hospital, Peking University Hepatology Institute, Beijing 100044, China.
J Proteome Res. 2007 Jul;6(7):2746-52. doi: 10.1021/pr0701759. Epub 2007 Jun 15.
In an effort to identify proteins involved in the disease process of acute liver failure (ALF), we investigated changes in the plasma proteome associated with d-galactosamine/lipopolysaccharide (GalN/LPS) treatment of BALB/c mice. The plasma samples from mice with ALF and control were screened for potential differences using two-dimensional electrophoresis followed by liquid chromatography-electrospray ionization-tandem mass spectrometry or matrix associated laser desorption ionization-time-of-flight mass spectrometry. The expression levels of candidate protein named phosphatidylethanolamine binding protein (PEBP) in plasma and liver, brain tissues were confirmed by western blot and RT-PCR analyses. Results were confirmed in plasma samples of human beings. Seven proteins existed in plasma of GalN/LPS-treatment animals only but not in controls. They included PEBP, regucalcin, Cu/Zn superoxide dismutase, glyoxalase 1, malate dehydrogenase, proteasome subunit alpha type 1, and HPMS haptoglobin precursor. Two proteins, proteasome subunit alpha type 5 and apolipoprotein A-I precursor, were up-regulated by GalN/LPS, and one protein, HPMS haptoglobin precursor, was down-regulated by this treatment. Western blot analysis confirmed the results that PEBP protein levels increased significantly in plasma and liver tissues only in ALF mice, but not in surviving mice treated with GalN/LPS. Further analysis revealed that GalN/LPS also induced up-regulation of PEBP mRNA levels in liver tissues. Importantly, plasma obtained from ALF patients, but not from healthy volunteers or from hepatitis patients, also contained detectable levels of PEBP. The present study show that PEBP may be a potential plasma biomarker for ALF diagnosis and participate in the pathphysiological process of ALF.
为了确定参与急性肝衰竭（ALF）疾病过程的蛋白质，我们研究了用d-半乳糖胺/脂多糖（GalN/LPS）处理BALB/c小鼠后血浆蛋白质组的变化。使用二维电泳，随后进行液相色谱-电喷雾电离-串联质谱或基质辅助激光解吸电离-飞行时间质谱，对ALF小鼠和对照小鼠的血浆样本进行潜在差异筛选。通过蛋白质免疫印迹和逆转录-聚合酶链反应分析，证实了名为磷脂酰乙醇胺结合蛋白（PEBP）的候选蛋白在血浆、肝脏和脑组织中的表达水平。在人类血浆样本中也证实了这些结果。GalN/LPS处理动物的血浆中仅存在7种蛋白质，而对照中不存在。它们包括PEBP、调钙蛋白、铜/锌超氧化物歧化酶、乙二醛酶1、苹果酸脱氢酶、蛋白酶体α亚基1型和HPMS触珠蛋白前体。两种蛋白质，蛋白酶体α亚基5型和载脂蛋白A-I前体，被GalN/LPS上调，一种蛋白质，HPMS触珠蛋白前体，被这种处理下调。蛋白质免疫印迹分析证实了以下结果：仅在ALF小鼠的血浆和肝脏组织中，PEBP蛋白水平显著升高，而在接受GalN/LPS处理的存活小鼠中则没有。进一步分析表明，GalN/LPS还诱导肝脏组织中PEBP mRNA水平上调。重要的是，从ALF患者而非健康志愿者或肝炎患者获得的血浆中也含有可检测水平的PEBP。本研究表明，PEBP可能是ALF诊断的潜在血浆生物标志物，并参与ALF的病理生理过程。
