Alzheimer?s Disease (AD) is a debilitating conditioned marked by accumulation of Ab and hyperphosphorylation of tau proteins thought to lead to neurodegeneration and cognitive decline. It has been hypothesized that Ab accumulation and tauopathy might result in damage to blood vessels that make up the blood brain barrier (BBB), which is estimated to contribute to ~50% of all dementias worldwide, including AD. Such BBB damage is thought to result in disease pathogenesis by increasing brain permeability and peripheral immune infiltration. Animal models of AD-related pathology, which rely on the overexpression or knock-in of established genetic mutations, have confirmed that the accumulation of A? and tau does indeed result in blood vessel abnormalities and blood- brain barrier (BBB) breakdown (Fig 1), which is associated with behavioral symptoms including cognitive dysfunction. In addition to cognitive decline, many AD patients also experience severe neuropsychiatric symptoms such as depression and anxiety. While the mechanisms of comorbid neuropsychiatric symptoms with AD are not well known, we have shown that chronic stress?a known risk factor for AD in humans?can in fact damage the BBB. Under the parent R01MH104559, my lab has been investigating whether pro-inflammatory cytokines such as interleukin 6 (IL-6) or immune cells themselves may diffuse more readily into the brain of stressed mice due to vascular damage. We have found that stress reduces expression of the tight junction protein claudin 5 (CLDN5) and leads to breakdown of the endothelial barrier allowing greater entry of IL-6 directly into brain reward regions like the nucleus accumbens (NAc) to impair social behavior and responses to natural rewards [15]. Interestingly, genetic mouse models of AD-related pathology confirm that they are indeed more sensitive to the behavioral effects of stress and exhibit age-related degeneration of the BBB, which leads to increased permeability. In this supplement we will examine the effects of chronic social stress on BBB integrity and stress-induced behaviors in well-established mouse models of AD-related pathology.

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Damage to the blood brain barrier (BBB) is thought to contribute to ~50% of all dementias worldwide, including Alzheimer's disease (AD). We find that stress, a known risk factor for the onset of AD, damages the blood brain barrier allowing peripheral immune signals to traffic to the brain and regulate stress behaviors. A deeper understanding of the interactions between stress, AD-related pathology and BBB damage will provide important mechanistic insight into the etiology of AD.

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Tonelli, Leonardo H
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Icahn School of Medicine at Mount Sinai
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Pfau, Madeline L; Ménard, Caroline; Russo, Scott J (2018) Inflammatory Mediators in Mood Disorders: Therapeutic Opportunities. Annu Rev Pharmacol Toxicol 58:411-428
Aleyasin, Hossein; Flanigan, Meghan E; Golden, Sam A et al. (2018) Cell-Type-Specific Role of ?FosB in Nucleus Accumbens In Modulating Intermale Aggression. J Neurosci 38:5913-5924
Calipari, Erin S; Godino, Arthur; Peck, Emily G et al. (2018) Granulocyte-colony stimulating factor controls neural and behavioral plasticity in response to cocaine. Nat Commun 9:9
Takahashi, Aki; Flanigan, Meghan E; McEwen, Bruce S et al. (2018) Aggression, Social Stress, and the Immune System in Humans and Animal Models. Front Behav Neurosci 12:56
Liu, Jia; Dietz, Karen; Hodes, Georgia E et al. (2018) Widespread transcriptional alternations in oligodendrocytes in the adult mouse brain following chronic stress. Dev Neurobiol 78:152-162
Wang, Jun; Hodes, Georgia E; Zhang, Hongxing et al. (2018) Epigenetic modulation of inflammation and synaptic plasticity promotes resilience against stress in mice. Nat Commun 9:477
Labonté, Benoit; Engmann, Olivia; Purushothaman, Immanuel et al. (2017) Sex-specific transcriptional signatures in human depression. Nat Med 23:1102-1111
Flanigan, Meghan; Aleyasin, Hossein; Takahashi, Aki et al. (2017) An emerging role for the lateral habenula in aggressive behavior. Pharmacol Biochem Behav 162:79-86
Brancato, Anna; Bregman, Dana; Ahn, H Francisica et al. (2017) Sub-chronic variable stress induces sex-specific effects on glutamatergic synapses in the nucleus accumbens. Neuroscience 350:180-189
Giannarelli, Chiara; Rodriguez, David T; Zafar, M Urooj et al. (2017) Susceptibility to chronic social stress increases plaque progression, vulnerability and platelet activation. Thromb Haemost 117:816-818

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