Multiple clinical studies suggest that heightened peripheral inflammation contributes to major depressive disorder (MDD) pathogenesis. Co-morbidity of inflammatory disease with MDD is highly prevalent, and MDD patients have a higher risk of developing those diseases. It has been hypothesized that circulating inflammatory molecules are released following chronic stress, penetrate the blood brain barrier (BBB), and affect neural circuits, mediating stress vulnerability and depression. However, despite years of intensive research into the role of cytokines in depression, we have very little direct evidence of how cytokines enter the brain and in which circuits they act. Recently, we have begun to investigate the effect of chronic social defeat stress (CSDS), a mouse model of stress that induces depression-like behavior, on BBB permeability. Endothelial cells and astrocytes play critical roles in maintaining vascular impermeability. Endothelial cells, via expression of tight junction proteins, establish the paracellular barrier between the perivascular space and brain parenchyma. Breakdown of the endothelial barrier can lead to infiltration of peripheral immune signals? such as IL-6?that we have shown previously to increase stress susceptibility. Our new data shows that 10 days of CSDS downregulates expression of the tight junction protein Cldn5 in the NAc of stress-susceptible mice leading to loss of integrity of the endothelial barrier, immune infiltration and expression of depression-like behaviors. Expanding upon these preliminary observations, we will probe the detailed molecular and cellular mechanisms by which peripheral immune signals interface with mood-related brain circuitry to control depression-like behaviors following social stress. By understanding how chronic stress affects the BBB we may be able to augment current antidepressant treatment or design new therapeutic strategies promoting vascular health by preventing BBB degeneration.
Major depressive disorder is associated with heightened peripheral inflammation that is casually linked to depression symptoms. Despite years of intensive research and ongoing clinical trials to test antidepressant efficacy of immune modulatory drugs that target systemic inflammation, it is still unclear how the peripheral immune system interfaces with mood-related brain circuitry to control depression-like behavioral responses. In this proposal we show that chronic stress induces neurovascular damage that weakens the blood brain barrier to allow immune infiltration and expression of depression-like behaviors.
| 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 |
| Pfau, Madeline L; Ménard, Caroline; Russo, Scott J (2018) Inflammatory Mediators in Mood Disorders: Therapeutic Opportunities. Annu Rev Pharmacol Toxicol 58:411-428 |
| 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 |
Showing the most recent 10 out of 27 publications
