Intranasal deferoxamine engages multiple pathways to decrease memory loss in the APP/PS1 model of amyloid accumulation

Abstract

In addition to the hallmark accumulation of amyloid and hyper-phosphorylation of tau, brain changes in Alzheimer’s disease are multifactorial including inflammation, oxidative stress, and metal dysregulation. Metal chelators have been explored as a less well known approach to treatment. One chelator currently being developed is deferoxamine (DFO), administered via the intranasal (IN) route. In the current study, APP/PS1 amyloid mice were treated with a chronic, low dose of IN DFO, subjected to a rigorous battery of behavior tests, and the mechanism of action was examined. Mice were treated 3x/week with 0.24C IN DFO for 18 weeks from 36 to 54 weeks of age, 4 weeks of behavior tests were performed that included both working and reference memory, anxiolytic and motor behaviors, and finally brain tissues were analyzed for amyloid, protein oxidation, and other proteins affected by DFO. We found that IN DFO treatment significantly decreased loss of both reference and working memory in the Morris and radial arm water mazes (p<0.05), and also decreased soluble Aβ40 and Aβ42 in cortex and hippocampus (p<0.05). Further, IN DFO decreased activity of GSK3β, and led to decreases in oxidative stress (p<0.05). These data demonstrate that low doses of IN DFO can modify several targets along the multiple pathways implicated in the neuropathology of Alzheimer’s, making it an attractive candidate for the treatment of this heterogeneous disease.