Alcohol drinking during early adolescence activates microglial cells and increases frontolimbic Interleukin-1 beta and Toll-like receptor 4 gene expression, with heightened sensitivity in male rats compared to females

Copyright © 2021 Elsevier Ltd. All rights reserved..

Adolescent drinking is risky because neural circuits in the frontal lobes are undergoing maturational processes important for cognitive function and behavioral control in adulthood. Previous studies have shown that myelinated axons in the medial prefrontal cortex (mPFC) are particularly sensitive to alcohol drinking, especially in males. Pro-inflammatory mediators like toll-like receptor 4 (TLR4) and interleukin-1 beta (IL1b) have been implicated in alcohol induced-inflammation and demyelination; thus, herein we test the hypothesis that voluntary alcohol drinking early in adolescence elicits a pro-inflammatory state that is more pronounced in the brain of males compared to females. Adolescent male and female Wistar rats self-administered sweetened alcohol or sweetened water from postnatal days 28-42 and separate sets of brains were processed for 1) immunolabeling for ionized calcium-binding adapter molecule 1 to analyze microglial cell morphology, or 2) qPCR analysis of gene expression of pro-inflammatory mediators. Binge drinking alcohol activated microglia in the mPFC and hippocampus of both males and females, suggesting that voluntary alcohol exposure initiates an inflammatory response. Il1b mRNA was upregulated in the mPFC of both sexes. Conversely, Tlr4 mRNA levels were elevated after drinking only in males, which could explain more robust effects of alcohol on myelin in this region in developing males compared to females. Il1b mRNA changes were not observed in the hippocampus, but alcohol elevated Tlr4 mRNA in both sexes, highlighting regional specificity in inflammatory responses to alcohol. Overall, these findings give insight into potential mechanisms by which low-to-moderate voluntary alcohol intake impacts the developing brain. This article is part of the special Issue on 'Vulnerabilities to Substance Abuse'.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:197

Enthalten in:

Neuropharmacology - 197(2021) vom: 01. Okt., Seite 108698

Sprache:

Englisch

Beteiligte Personen:

Silva-Gotay, Andrea [VerfasserIn]
Davis, Jillian [VerfasserIn]
Tavares, Elizabeth R [VerfasserIn]
Richardson, Heather N [VerfasserIn]

Links:

Volltext

Themen:

Adolescence
Alcohol
Binge drinking
Cytokines
Development
Female
Hippocampus
IL1B protein, rat
Iba1
Il1b
Interleukin-1 beta
Interleukin-1beta
Journal Article
MPFC
Male
Microglia
Neuroinflammation
Operant self-administration
Prefrontal cortex
RNA, Messenger
Rats
Research Support, N.I.H., Extramural
Sex differences
Tlr4
Tlr4 protein, rat
Toll-Like Receptor 4
Toll-like receptor 4

Anmerkungen:

Date Completed 07.02.2022

Date Revised 30.12.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.neuropharm.2021.108698

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM327981806