Regulating role of Pleurotus ostreatus insoluble dietary fiber in high fat diet induced obesity in rats based on proteomics and metabolomics analyses

This study aims to reveal the effects of Pleurotus ostreatus insoluble dietary fiber (POIDF) on liver protein and cecal metabolites in obese rats and its potential mechanism by intestinal microbes. It was found that POIDF contained the structural characteristics of cellulose and hemicellulose, as well as amorphous diffraction peaks. POIDF could reduce the body weight and organ index of obese rats, regulate dyslipidemia, and improve the pathological changes of liver and epididymis fat. Further experimental results showed that POIDF could regulate the abundance of bacteria related to lipid metabolism, and maintain intestinal homeostasis. The metabolomics results showed that the fatty acyls pathway in the cecum contents was the pathway with the highest concentration of small molecule metabolites. POIDF supplementation regulated the expression of liver key proteins, as well as biosynthesis of amino acids, steroid biosynthesis, arachidonic acid metabolism and PPAR signaling pathway. Omics association analysis found that POIDF could further regulate liver proteins and their signaling pathways, regulate the levels of fatty acyls and amino acid metabolites in the gut and the enrichment of related pathways, and play a therapeutic or preventive role in obesity after degradation by intestinal microbiota.