LABELING OF BRAIN MICROCIRCULATION AFTER SYSTEMIC ADMINISTRATION OF MELATONIN-FLUORESCEIN CONJUGATE IN HEALTHY MICE

We hypothesized that melatonin could be a carrier for small cargo of therapeutic molecule/s that can cross the BBB into the brain. To demonstrate the proof of concept, custom synthesized MelatoninFluorescein conjugate was administered intraperitoneally in healthy adult C57BL/6 mice. Confocal laser imaging showed that mice that received pretreatment with Colchicine and then MelatoninFluorescein conjugate, displayed intense cerebral microvascular labeling throughout the brain; the labeling was more intense in the vascular wall, endothelial cells and intravascular trafficking leukocytes, only a limited amount of the Melatonin-Fluorescein was seen in the adjacent neuropil.