High-fat intake induces gut microbiota disorders, inflammatory responses and oxidative stress in Nyctereutes procyonoides

Abstract The Nyctereutes procyonoides is highly regarded in the farming and leather industries because of the high value of its fur, which renders artificial feeding a crucial aspect. However, high-fat diets have always been associated with a variety of digestive disorders. This study aimed to investigate the impact of high-fat diets on the gut microbiota and the mechanisms of gut damage in Nyctereutes procyonoides. 16S rRNA sequencing demonstrated that high-fat diets caused diarrhea and intestinal damage through alterations in the gut microbiota: a decrease in the abundance of Firmicutes, an increase in the abundance of Proteobacteria and Actinobacteria, and an increase in the abundance of Enterococcaceae, Escherichia coli-Shigella, Clostridium and Lactobacillus. Subsequently, changes in metabolic pathways, such as amino and fatty acid pathways, were identified by KEGG and COG enrichment analysis, and the TLR4/NF-κB/NLRP3 inflammatory signaling pathway was shown to be activated by high-fat diets. In addition, high-fat diets lead to the accumulation of ROS and MDA and reduce the activity of the antioxidant enzymes GSH-PX and SOD. Correspondingly, the levels of proinflammatory cytokines (IL-6, IL-1β and TNF-α) were significantly increased, and the apoptosis and necrosis signaling pathways of colonic cells were detected, causing a dramatic decrease in the expression of intestinal tight junction proteins (Occludin, E-cadherin, ZO-1 and ZO-2). In conclusion, high-fat diets altered the structure of the Nyctereutes procyonoides gut microbiota community and led to colon damage. This study provides new insights into the intestinal health of Nyctereutes procyonoides. Graphical Abstract