Serum metabolomics analysis of the intervention effect of whole grain oats on insulin resistance induced by high-fat diet in rats

This study aimed to evaluate the intervention effect of whole grain oats (WGO) on a high-fat (HF) diet induced insulin resistance (IR) rat model by metabolomic approach. Sixty rats were randomly allocated into six groups, including the control group, HF group, and four oat-intervention groups. Rats in the control group and HF group were respectively given the standard diet and HF diet respectively. The four oat-intervention groups were fed with a special HF diet, in which sucrose and starch in the HF diet were replaced by whole grain oats powder in different proportions of 25%, 50%, 75%, and 100% respectively. After 8-week feeding, serum samples of all rats were collected for biochemical detection, and the metabolomics analysis was carried out by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). The results showed that the WGO could regulate body weight, blood glucose, blood lipid, and inflammatory response, which indicated that WGO could prevent IR induced by the HF diet, and it was effective enough by 50% WGO replacement. By serum metabolomics analysis, six differential metabolites closely related to WGO intervention on IR were found, and the related metabolic pathways involved energy metabolism, amino acid metabolism, and lipid metabolism.