found that Amuc_1100 can improve chronic unpredictable mild stress (CUMS)-induced depression-like behavior and CUMS-induced downregulation of serotonin in the serum and colon of mice, restore gut dysbiosis, upregulate BDNF, and inhibit inflammation in the hippocampus (Cheng et al., 2021). Here, BDNF is linked to depressive disorder.