TLR4 and major depressive disorder: Mo et al. [113] found in an LPS (1 mg/kg)-induced inflammatory depression mice model that salidroside (ig 25 mg/kg, administered for 2 w) could significantly improve depression-like behavior (sugar water preference test, forced swimming test, suspension test), and down-regulate TNF-α, IL-1β, TLR4, and NLRP3 levels in brain tissue.