Fig. 4

Changes in behavioral performance, cytokine expression, and TLR4/NF-κB signaling in response to recombinant proteins. After treatment with recombinant Mrp8, Mrp14, or Mrp8/14, depressive-like behaviors were determined by the sucrose preference test and tail suspension test (TST). a Both Mrp14- and Mrp8/14-treated mice exhibited reduced sucrose preference compared with the vehicle group (n = 10 mice/group). b All of the three recombinant proteins could extend the immobility time in TST compared with vehicle treatment (n = 5–6 mice/group). c The results of RT-PCR of the mRNA changes of proinflammatory cytokines and IBA-1 in the hippocampus. n = 4–5 mice/group for TNF-α, IL-6, and IBA-1, n = 3–5 mice/group for IL-1β. d–i Western blot analyses showed that hippocampal TLR4/NF-κB signaling was activated after these protein treatments, while the RAGE protein was not significantly changed among these groups (n = 4 mice/group). *p < 0.05, **p < 0.01, ***p < 0.001 between two indicated groups. The data are presented as the mean ± SEM