For instance, by using a murine model of PD, it has been shown that the oral administration of the engineered strain Lactococcus lactis cremori that continually expresses glucagon-like peptide-1 (GLP-1) (MG1363-pMG36e-GLP-1) can increase TH expression, reduce locomotor and memory impairments, as well as α-synuclein production, attenuate neuroinflammation via down-regulating the TLR4/NF-κB pathway and some pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α), arrest microglia and astrocyte activation, and restore GM dysbiosis [349,350]. The gene discussed is GLP1R; the disease is memory impairment.