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bioRxiv · 10.1101/2022.05.07.491031

Oxytocin attenuates microglial activation and restores social and non-social memory in the APP/PS1 mouse model of Alzheimer's disease

Abstract

Alzheimers disease (AD) is the main cause of dementia in the elderly and is characterized by memory loss, social withdrawal and neurodegeneration, eventually leading to death. Brain inflammation has emerged as a key pathogenic mechanism in AD. We hypothesized that oxytocin, a pro-social hypothalamic neuropeptide with anti-inflammatory properties, could have therapeutic actions in AD. We investigated oxytocin production in mouse models of AD, and evaluated the therapeutic potential of intranasal oxytocin. We observed lower levels of hypothalamic oxytocin in wild-type mice following brain infusion of amyloid-{beta} oligomers (A{beta}Os), as well as in APP/PS1 AD model mice. Treatment of APP/PS1 mice with intranasal oxytocin reduced microglial activation and favored deposition of A{beta} in dense core plaques, a potentially neuroprotective mechanism. Oxytocin further alleviated social and non-social memory impairments in APP/PS1 mice. Our findings point to oxytocin as a potential therapeutic target to reduce brain inflammation and correct memory deficits in AD.

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Selles, M. C., Fortuna, J. T. S., de Faria, Y. P. R., Longo, B. M., Froemke, R., Chao, M. V., Ferreira, S. T.. 2022-05-08. Oxytocin attenuates microglial activation and restores social and non-social memory in the APP/PS1 mouse model of Alzheimer's disease. https://doi.org/10.1101/2022.05.07.491031

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