高脂血症对胰腺组织损伤机制的蛋白质组学分析

Characterization of proteins in hyperlipidemia pancreas using differential gel electrophoresis and tandem mass spectrometry

目的探讨高脂血症对大鼠胰腺的损伤机制。方法采用断乳1周雄性SD大鼠，随机分成2组，各5只。一组为高脂血症组，喂以高脂饮食，另一组为对照组，喂以普通饲料。实验6周后处死动物，取胰腺组织，裂解提取蛋白质。采用相差凝胶电泳（DIGE）和二极质谱技术，检测两组胰腺组织蛋白质差异，并用Western blotting验证。结果高脂血症组胰腺与正常胰腺相比，上调蛋白质3种，其中精氨酸酶Ⅱ、甘氨酸脒基转移酶、核糖核酸酶抑制剂分别为对照组的2．19倍、1．82倍和1．12倍；下调蛋白质11种，酪氨酰tRNA合成酶、α-淀粉酶、脂肪酶、DJ-1蛋白和Cu、zn超氧化物歧化酶等较对照组分别下降2．48倍、2．37倍、1．85倍、1．73倍和1．65倍（P〈0．05）。Western blotting显示高脂血症组胰腺的精氨酸酶Ⅱ表达较对照组明显增强，α-淀粉酶表达较对照组明显减弱。结论高脂血症胰腺组织中精氨酸酶升高可能是高三酰甘油对胰腺造成损伤的机制之一，而淀粉酶和脂肪酶下降可能为胰腺自身保护机制。

Objective To investigate the mechanism of hyperlipidemia on pancreas of rats by comparative proteomic analysis. Methods Ten male SD rats were randomly divided into two groups, the experimental group was fed with high lipid forage and the control group was fed with normal food. Pancreatic samples from the two groups were harvested six weeks later. Differential protein analysis was performed using differential in-gel electrophoresis （DIGE）, and characterizing the protein biomarkers using tandem mass spectrometry. Western blot was used to confirm the expression of significantly changed proteins. Results Compared to the normal pancreas tissue, a total of 3 protein spot-features were found to be significantly increased and 11 significantly decreased in pancreatic samples with hyperlipidemia. Significantly increased proteins in hyperlipidemia pancreatic samples were arginase Ⅱ, ribonuclease inhibitor and glycine amidinotransferase, which increased by 2. 19, 1. 82 and 1. 12 fold, respectively. Significantly decreased proteins in hyperlipidemia group were tyrosyl-tRNA synthetase, alpha-amylase, triacylglycerol lipase, DJ-1 protein, Cu, Zn superoxide dismutase, which dicreased by 2.48, 2.37, 1. 85, 1.73 and 1.65 folds, respectively. Western blot analysis revealed increased arginase H levels and decreased alpha-amylase in pancreatic samples with hyperlipidemia. Conclusions Pancreas was possibly injured by hyperlipidemia via increase of arginase II. Decreased amylase and lipase may be the protection mechanism of pancreas.