Chronic adolescent stress sex-specifically alters central and peripheral neuro-immune reactivity in rats

Copyright © 2018 Elsevier Inc. All rights reserved..

Adversity during development is a reliable predictor of psychiatric disorders such as depression and anxiety which are increasingly recognized to have an immune component. We have previously demonstrated that chronic adolescent stress (CAS) in rats leads to depressive-like behavior in adulthood along with long-lasting changes to the hypothalamic-pituitary-adrenal axis and pro-inflammatory cytokine induction in the hippocampus. However, the mechanisms by which CAS promotes hippocampal inflammation are not yet defined. Here we tested the hypothesis that a history of CAS exaggerates induction of the pro-inflammatory NFκB pathway in the adult rat hippocampus without compromising the peripheral immune response. We also assessed potential sex differences because it is unclear whether females, who are twice as likely to suffer from mood disorders as males, are disproportionally affected by stress-primed inflammation. Male and female adolescent rats underwent a CAS paradigm or received no stress. Six weeks following the last stressor, all rats received a single systemic injection of either lipopolysaccharide or vehicle to unmask possible immune-priming effects of CAS. An NFκB signaling PCR array demonstrated that CAS exaggerated the expression of NFκB-related genes in the hippocampus of both males and females. Interestingly, targeted qPCR demonstrated that CAS potentiated the induction of hippocampal IL1B and REL mRNA in female rats only, suggesting that some immune effects of CAS are indeed sex-specific. In contrast to the hippocampal findings, indices of peripheral inflammation such as NFκB activity in the spleen, plasma IL-1β, IL-6, TNF-α, and corticosterone were not impacted by CAS in female rats. Despite showing no pro-inflammatory changes to hippocampal mRNA, male CAS rats displayed lower plasma corticosterone response to LPS at 2 h after injection followed by an exaggerated plasma IL-1β response at 4 h. This potentially blunted corticosterone response coupled with excessive innate immune signaling in the periphery is consistent with possible glucocorticoid resistance in males. In contrast, the effects of CAS manifested as excessive hippocampal immune reactivity in females. We conclude that while a history of exposure to chronic adolescent stress enhances adult immune reactivity in both males and females, the mechanism and manifestation of such alterations are sex-specific.

Medienart:

E-Artikel

Erscheinungsjahr:

2019

Erschienen:

2019

Enthalten in:

Zur Gesamtaufnahme - volume:76

Enthalten in:

Brain, behavior, and immunity - 76(2019) vom: 20. Feb., Seite 248-257

Sprache:

Englisch

Beteiligte Personen:

Bekhbat, Mandakh [VerfasserIn]
Howell, Paul A [VerfasserIn]
Rowson, Sydney A [VerfasserIn]
Kelly, Sean D [VerfasserIn]
Tansey, Malú G [VerfasserIn]
Neigh, Gretchen N [VerfasserIn]

Links:

Volltext

Themen:

Adolescence
Corticosterone
Cytokines
Female
IL-1β
IL-6
Interleukin-1beta
Journal Article
Lipopolysaccharides
NFκB
NF-kappa B
Neuroinflammation
Rat
Receptors, Glucocorticoid
Research Support, N.I.H., Extramural
Sex differences
Stress
TNF-α
W980KJ009P

Anmerkungen:

Date Completed 28.02.2020

Date Revised 28.02.2020

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.bbi.2018.12.005

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM291808166