A study found that AD-associated intestinal flora (characterized by Bacteroidetes) enrichment could enhance microglial cell activation and neuroinflammation by activating the C/EBPβ/AEP pathway and upregulating pro-inflammatory PUFA metabolism by activating the C/EBPβ/AEP pathway, thereby promoting microglial cell activation and neuroinflammation, thereby promoting AD pathology and cognitive impairment. This evidence concerns the gene CEBPB and Alzheimer disease.