Fig. 6

In situ visualization of critical metabolites and metabolic enzymes in glutamine and glutamate metabolism changed by CQDs in brain of mice. (a) MS images and levels of D/L-glutamine and D/L-glutamate in different regions of brain; (b) GLS/GS-mediated metabolic process of interconversion between D/L-glutamine and D/L-glutamate; (c) The newly constructed MSI based on the ion intensity ratio of D/L-glutamine and D/L-glutamate; Representative IHC staining showed the expression of GLS (d, e) and GS (f, g) in different regions of brain tissue section and their IHC scores. Olfactory bulb (OB), Cortex (COR), Hippocampus (HIP), Corpus Striatum (CS), Midbrain (MB), Cerebellum (CE), Nucleus Accumbens (NAcc), Lateral Habenula Nucleus (LHB) and Zona Incerta (ZI). Data are showed as mean ± SD of three independent experiments. (*P < 0.05, **P < 0.01, ***P < 0.001)