煎炸油及抗性淀粉干预对大鼠基因表达的影响

发布时间：2018-08-16 15:04

【摘要】：食用油在反复煎炸过程中发生氧化、水解和聚合等一系列化学反应,导致品质下降,不仅影响食品的质构和风味,还产生许多有毒物质,严重影响健康。抗性淀粉作为一种新型膳食纤维,具有保护肠道健康、降低血糖水平、调节脂质代谢等作用。本文研究了煎炸油和抗性淀粉干预对大鼠肝脏基因表达的影响。利用复杂网络分析方法,探讨煎炸油损伤肝脏可能的分子机制以及抗性淀粉可能的保护作用机制。与新鲜油脂组相比,129个基因在摄入煎炸油后表达明显上调,而300个基因呈现下调。我们从RGD数据库搜集了 429个差异表达基因参与的生物通路信息,并以生物通路为节点,共有基因为网络的边构建基因-生物通路网络。统计结果显示,网络包括48个节点和67条边,平均度为2.75,平均路径长度为4.0964,聚集系数为0.3549,网络具有明显的小世界性和无标度特征。利用中心性指标筛选出神经酰胺信号通路、细胞周期通路等19条关键通路,选取Srebf1、Sgk1、Insig1、Ccnd1等19个枢纽基因及表达倍数较大的基因作为关键基因进行深入分析。结果表明,煎炸油可通过多条途径诱导细胞凋亡、阻滞细胞周期、严重影响细胞结构功能的完整,导致胰岛素通路紊乱,损伤血管内皮功能进而诱发高血压和动脉粥样硬化等疾病,还可使机体免疫功能下降,生长缓慢,体重降低。抗性淀粉干预后,与煎炸油组相比,表达上调基因219个,下调基因143个。绘制的通路网络包括48个节点和57条边,平均度为2.42,平均路径长度仅有3.5330,聚集系数为0.6401,网络具有小世界和无标度网络的特征。其中30个通路与FO-DO网络中的通路一致,涉及20个共同基因表达水平相反、绝对值相近。11个基因为FO-DO网络中的关键基因,表明抗性淀粉可调节煎炸油所引起的基因异常表达趋于正常水平。利用中心性指标从DO-RS网络中筛选出胰岛素信号转导通路、JAK-STAT信号转导途径等9条关键通路,选取Srebf1、Sgk1、Socs2、Irs2等13个枢纽基因及表达倍数较大的基因作为关键基因进行深入分析。结果表明,抗性淀粉可预防煎炸油引起的胰岛素抵抗、调节机体免疫功能、保护细胞结构功能的完整、增强机体解毒能力,同时还可保持内皮细胞的结构及功能的完整,从而对煎炸油所引起的高血压和动脉粥样硬化具有一定的预防作用。
[Abstract]:A series of chemical reactions, such as oxidation, hydrolysis and polymerization, occur in cooking oil in the process of repeated frying, resulting in a decline in quality, which not only affects the texture and flavor of food, but also produces many toxic substances, which seriously affect health. As a new dietary fiber, resistant starch has the functions of protecting intestinal health, lowering blood sugar level and regulating lipid metabolism. The effects of fried oil and resistant starch on gene expression in rat liver were studied. The possible molecular mechanism of liver injury by fried oil and the protective mechanism of resistant starch were studied by using complex network analysis method. Compared with fresh oil group, 129 genes were up-regulated after frying oil intake, while 300 genes were down-regulated. We collected 429 biological pathways involved in differentially expressed genes from the RGD database. We used biological pathways as nodes and shared a common base to construct a gene-biological pathway network because of the edge of the network. The statistical results show that the network consists of 48 nodes and 67 edges, the average degree is 2.75, the average path length is 4.0964, and the aggregation coefficient is 0.3549. Nineteen key pathways, such as ceramide signaling pathway and cell cycle pathway, were screened by central indexes. Nineteen pivotal genes, such as Srebf1Sgk1Sgk1Insig1Ccnd1 and genes with large expression times, were selected as key genes for in-depth analysis. The results showed that frying oil could induce apoptosis, block cell cycle, seriously affect the integrity of cell structure and function, and lead to the disturbance of insulin pathway. The injury of vascular endothelial function can induce hypertension and atherosclerosis, but also can reduce immune function, slow growth and weight loss. Compared with fried oil group, 219 genes were up-regulated and 143 genes were down-regulated after intervention with resistant starch. The network is composed of 48 nodes and 57 edges, the average degree is 2.42, the average path length is only 3.5330, and the aggregation coefficient is 0.6401. The network has the characteristics of small world and scale-free network. 30 of these pathways are identical to those in FO-DO networks, involving 20 common genes that are expressed at the opposite level and have similar absolute values. 11 bases are due to the key genes in the FO-DO network. The results showed that resistant starch could regulate the abnormal gene expression induced by frying oil. Nine key pathways, such as JAK-STAT signal transduction pathway, were screened from DO-RS network by central index. Thirteen pivotal genes, such as Srebf1, Sgk1Sgk1Sgk1Socs2Irs2 and genes with high expression times, were selected as key genes for further analysis. The results showed that resistant starch could prevent insulin resistance induced by fried oil, regulate immune function, protect the integrity of cell structure and function, enhance the ability of detoxification, and keep the structure and function of endothelial cells intact. It can prevent hypertension and atherosclerosis caused by frying oil.
【学位授予单位】：天津科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TS201.4;TS221

【参考文献】