It also increased the expression of SCFAs, alleviated gut barrier damage, and upregulated the BDNF-TrkB-ERK1/2-CREB signaling pathway to reduce neuronal damage and enhance the expression of Syn and PSD-95, which may improve chronic ketamine-induced anxiety-like behaviors, PPI impairments, and spatial learning and memory deficits. The gene discussed is MAPK3; the disease is Anxiety.