Golgi Apparatus Polarity Indicates Depression-Like Behaviors of Mice Using in Vivo Fluorescence Imaging

Depression is associated with decreased expression of brain-derived neurotrophic factor (BDNF) which assembled in Golgi apparatus. The changes might be closely related to variation in Golgi apparatus polarity. Thus, developing a nondestructive method to detect polarity in living cells and in vivo can facilitate accurate diagnosis and prognosis of depression. Herein, we created a new near-infrared Golgi-targetable fluorescent probe (Golgi-P) in which the merocyanine and benzoyl difluoroboronate moieties sense polarity changes. Golgi-P exhibited a decrease in fluorescence intensity and red-shift of maximum emission wavelength as the increase in polarity. Using Golgi-P, we discovered distinctly higher polarity in brains of mice with depression phenotype for the first time. Furthermore, our results disclosed that the elevation of polarity could due to the reduced synthesis of BDNF. Altogether, this study offers a new strategy for the accurate diagnosis of depression.