高脂饮食对小鼠胃蛋白质组表达水平的影响

Effect of high fat diet on proteome in mice stomachs

摘要:

以高脂饮食小鼠为模型，多角度分析高脂饮食对小鼠胃蛋白组表达的影响。实验小鼠 (C57BL/6)随机分配两组，实验组食用高脂饲料，对照组食用正常饲料，喂养110 d后，把胃组织分为前胃、胃体和胃窦3个区分别进行蛋白质谱鉴定，随后比较两组实验的蛋白表达谱，分别筛选两组之间的差异蛋白以及胃分区的差异蛋白 (差异倍数≥2)，并对其进行GO富集及蛋白相互作用网络分析。对照组和实验组共鉴定到9 307种蛋白，筛选特异性肽段≥1且重复实验中至少鉴定到2次的蛋白，最后剩余4 066种蛋白，其中对照组3 654种，实验组3 832种。进一步从生物功能角度整体分析了胃组织的蛋白表达谱，结果发现实验组小鼠胃组织中高表达蛋白主要参与蛋白稳定和运输等生物学过程。而在对胃分区差异蛋白的功能分析表明，前胃主要参与角质化和肌动蛋白组装相关生物学过程，且受饮食影响程度较小；胃体和胃窦主要执行消化功能，高脂饮食后对胃的基本消化功能并无显著影响，但与对照组相比，参与蛋白转运和脂肪代谢相关生物学过程的蛋白显著高表达。

Abstract:

To explore the effect of high fat diet on proteome in mice stomachs, we constructed a model in which the mice were fed with high fat diet as the high fat diet (HFD) group or normal diet as the control (CTRL) group for 110 days. The stomachs were collected and divided into three regions (forestomach (F), corpus (C) and antrum (A)) for protein extraction and mass spectrometry analysis. Of all 9 307 identified proteins in two groups, 4 066 proteins (HFD: 3 832, CTRL: 3 654) were strictly identified by at least one unique peptide and identified twice in three replicates. Using gene ontology (GO) and interaction network analysis we analyzed differentially expressed proteins (fold change≥2) in two groups or between regions. In the whole stomach tissues, proteins up-regulated in HFD group mainly were associated with protein stabilization and protein transport. Differentially expressed proteins between regions showed that forestomach was related to the biological process of keratinization and actin assembly, while corpus and antrum mainly performed digestive function. Compared with forestomach, the corpus and antrum were more affected by the diet. Though there was no significant effect on the basic digestive function of the stomach, proteins that were involved in protein transport and lipid metabolism-related biological processes were significantly highly expressed in HFD group.