Near-Infrared Fluorescent Probe for the In Situ Visualization of Oxidative Stress in the Brains of Neuroinflammatory and Schizophrenic Mice

[Image: see text] Schizophrenia is a common mental disorder with unclear mechanisms. Oxidative stress and neuroinflammation play important roles in the pathological process of schizophrenia. Superoxide anion (O(2)(•–)) is an important oxidative stress biomarker in vivo. However, due to the existence of the blood–brain barrier (BBB), few near-infrared (NIR) fluorescent probes have been used for the sensing and detection of O(2)(•–) in the brain. With this research, we developed the first near-infrared fluorescent probe (named CT–CF(3)) for noninvasive detection of endogenous O(2)(•–) in the brain of mice. Enabling fluorescence monitoring of the dynamic changes in O(2)(•–) flux due to the prolonged activation of microglia in neuroinflamed and schizophrenic (SZ) mice brains, thereby providing direct evidence for the relationship between oxidative stress, neuroinflammation, and schizophrenia. Furthermore, we confirmed the O(2)(•–) burst in the brains of first-episode schizophrenic mice and assessed the effect of two atypical antipsychotic drugs (risperidone and olanzapine) on redox homeostasis.