Additionally, studies suggested that Bifidobacterium short MCC1274 could improve cognitive dysfunction in AD by increasing the bioavailability of potential intestinal antioxidant metabolites (such as soy isoflavones and indole derivatives of tryptophan), reducing the level of Aβ42, inhibiting tau phosphorylation, improving synaptic proteins, and inhibiting microglia activation (Ohno et al., 2022; Abdelhamid et al., 2022a,b). This evidence concerns the gene MAPT and Alzheimer disease.