Altered the intestinal microflora of AD mice, enriched the short-chain fatty acid producing flora, increased propionic acid (PA) content in feces and serum of AD mice, was positively correlated with the number of parasitobacter Kim and Lactobacillus plantarum in the intestine, and inhibited the inflammatory response of intestine and skin of AD mice through the G-protein coupled receptor/NF-κB pathway. The gene discussed is NFKB1; the disease is Alzheimer disease.