Doxycycline counteracts neuroinflammation restoring memory in Alzheimer's disease mouse models

• DOI: 10.1016/j.neurobiolaging.2018.06.002
• Publication Date: 2018-06-12T11:37:00Z
• Authors: Claudia Balducci; Giulia Santamaria; Pietro La Vitola; Edoardo Brandi; Federica Grandi; Arturo Roberto Vi...; Marten Beeg; Marco Gobbi; Mario Salmona; Simone Ottonello; Gianluigi Forloni
• Keywords: Memory Impairment

β-Amyloid oligomers (AβOs) and neuroinflammation are 2 main culprits to counteract in Alzheimer's disease (AD). Doxycycline (DOXY) is a second generation antibiotic of the tetracycline class that are promising drugs tested in many clinical trials for a number of different pathologies. DOXY is endowed with antiamyloidogenic properties and better crosses the blood-brain barrier, but its efficacy has never been tested in AD mice. We herein show that 15- to 16-month-old APP/PS1dE9 (APP/PS1) AD mice receiving DOXY under different treatment regimens recovered their memory without plaque reduction. An acute DOXY treatment was, also, sufficient to improve APP/PS1 mouse memory, suggesting an action against soluble AβOs. This was confirmed in an AβO-induced mouse model, where the AβO-mediated memory impairment was abolished by a DOXY pretreatment. Although AβOs induce memory impairment through glial activation, assessing the anti-inflammatory action of DOXY, we found that in both the AβO-treated and APP/PS1 mice, the memory recovery was associated with a lower neuroinflammation. Our data promote DOXY as a hopeful repositioned drug counteracting crucial neuropathological AD targets.