Fig. 3

Methylglyoxal (MGO) suppressed tryptophan (Trp) and neurotransmitter levels in the plasma and brain of mice. (A–C) Levels of Trp, 5-hydroxytryptophan (5-HTP), and serotonin (5-HT) in the mice plasma. (D–F) The levels of dopamine (DA), epinephrine (EPI), and serotonin (5-HT) in the mice whole brain. (G) The TPH2 levels in the DG, CA3, CA1) and cortex (CX) regions by IHC staining assay. Scale bar: 100 μm (20× magnification). The TPH2 intensity were conducted by calculating the expression in the DG, CA3, CA1, and CX from selected fields per image. The values were calculated using ImageJ software. All data presented as mean ± SEM (n = 3). ^#p < 0.05, ^##p < 0.01, and ^###p < 0.001 vs. control group (CON). HP, hippocampus