Research On The Metabolic Disorders Of Gut Microbiota Induced By Deep-Fried Oil In Rats

Deep frying in oil is a popular cooking method around the world. However, the safety of deep-fried edible oil, which is ingested with fried food, is a concern, because the oil is exposed continuously to be re-used in high temperature,leading to a number of chemical reactions,such as hydrolysis,oxidation and polymerization. Thus,this study was investigated the changes in oxidative stress metabolism and gut microbiota in rats following deep-fried oil consumption and explores the mechanisms involved in above alterations,which may provide the guideline for designing health diet.Deep-fried oil was prepared following a published method. Adult male Wistar rats were randomly divided into three groups (n = 8/group). Group 1: basal diet without extra oil consumption (Control); Group 2: basal diet supplemented with non-heated canola oil(NEO); Group 3: basal diet supplemented with deep-fried canola oil (DFEO). One point five milliliters (1.5 mL) of non-heated or heated oil were fed by oral gavage using a feeding needle once daily for 6 consecutive weeks. Effect of DFEO on rats body weight, oxidative stress metabolism gut microbiota were analyzed using techniques of RNA sequencing,High-throught Sequencing (HTS) platform, etc. The gut microbiota composition was investigated by Illumina HiSeq high-throughput sequencing of the V4 region of the 16S rRNA gene compared with GreenGene databases. By calculating Simpson index, Shannon index, Ace index, Chao index, Observed Species index and cluster analysis, we can understand the abundance and diversity of the gut microbiota in these rats and analyse the structure of gut microbiota and their symptoms of distribution in different levels.Among the three groups, DFEO group diet resulted in a lowest rat body weight.Comparison of NEO group versus DFEO group, body metabolism was found to be significantly changed, indicating that inhibition of oxdative stress metabolism may be a response to the reduction in energy metabolism in the rats of DFEO group. Histological analysis of gastrointestinal tract demonstrated several changes induced by DFEO on gut microbiota with associated destruction of endocrine tissue and the evidence of inflammation. Related gene analysis indicated that the down-regulation of VEGF、 Hmox1 、Igfbpl 、 Pml seems to be highly associated with the inhibition of oxdative stress metabolism.With the methods of HTS, the abundance and diversity of gut microbiota in rats which were in NEO and DFEO were lower compared with the Control group. In particular, microbiota data showed that rats in DFEO group had the lowest proportion of Prevotella and the highest proportion of Erysipelotrichaceae among the three groups.