Fig. 10

Tryptophan (Trp) mitigated methylglyoxal (MGO)-induced depression and memory loss by regulating the AD and HPA axis, glyoxalase system, oxidative stress, and inflammation markers in mice (A, B) The secreted levels of IL-6 and TNF-α by ELISA assay kit. (C) CAT activity by colorimetric assay kit. (D) The expressed levels of p-Tau, Tau, APP, GLO-I, GLO-II, GR, p-ERK1/2, ERK1/2, p-p38, p38, p-NF-kB, NF-kB, and GAPDH by western blotting assay. (E) Representative Iba-1 immunofluorescent red signal in brain. Scale bar: 100 μm (10× magnification) – 200 μm (4× magnification). The activated microglia in hippocampus (HP) and cortex (CX) was represented as a region of interest (ROI) intensity ratio (%). The values are presented as mean ± SEM (n = 3). ^##p < 0.01 and ^###p < 0.001 vs. control group (CON). ^*p < 0.05, ^**p < 0.01 and ^***p < 0.001 vs. MGO-induced group (MGO). CON, control group. MGO, 65 mg/kg of MGO rectal injection group. MGO + Trp, 65 mg/kg of MGO rectal injection with 40 mg/kg of Trp oral administration group