Atypical microglial response to biodiesel exhaust in healthy and hypertensive rats

Christen L. Mumaw, Michael Surace, Shannon Levesque, Urmila P. Kodavanti, Prasada Rao S Kodavanti, Joyce E. Royland, Michelle Block

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Accumulating evidence suggests a deleterious role for urban air pollution in central nervous system (CNS) diseases and neurodevelopmental disorders. Microglia, the resident innate immune cells and sentinels in the brain, are a common source of neuroinflammation and are implicated in air pollution-induced CNS effects. While renewable energy, such as soy-based biofuel, is of increasing public interest, there is little information on how soy biofuel may affect the brain, especially in people with preexisting disease conditions. To address this, male spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) rats were exposed to 100% Soy-based Biodiesel Exhaust (100SBDE; 0, 50, 150 and 500μg/m3) by inhalation, 4h/day for 4 weeks (5 days/week). Ionized calcium-binding adapter molecule-1 (IBA-1) staining of microglia in the substantia nigra revealed significant changes in morphology with 100SBDE exposure in rats from both genotypes, where SHR were less sensitive. Aconitase activity was inhibited in the frontal cortex and cerebellum of WKY rats exposed to 100SBDE. No consistent changes occurred in pro-inflammatory cytokine expression, nitrated protein, or arginase1 expression in brain regions from either rat strain exposed to 100SBDE. However, while IBA-1 mRNA expression was not modified, CX3CR1 mRNA expression was lower in the striatum of 100SBDE exposed rats regardless of genotype, suggesting a downregulation of the fractalkine receptor on microglia in this brain region. Together, these data indicate that while microglia are detecting and responding to 100SBDE exposure with changes in morphology, there is reduced expression of CX3CR1 regardless of genetic background and the activation response is atypical without traditional inflammatory markers of M1 or M2 activation in the brain.

Original languageEnglish (US)
JournalNeuroToxicology
DOIs
StateAccepted/In press - Jun 1 2016

Fingerprint

Biofuels
Microglia
Rats
Brain
Preexisting Condition Coverage
Inbred WKY Rats
Central Nervous System Diseases
Air Pollution
Inbred SHR Rats
Neurology
Genotype
Air pollution
Renewable Energy
Aconitate Hydratase
Calcium
Messenger RNA
Frontal Lobe
Chemical activation
Substantia Nigra
Cerebellum

Keywords

  • Air pollution
  • Atypical activation
  • Biodiesel
  • Brain
  • Microglia
  • Neurotoxicity

ASJC Scopus subject areas

  • Neuroscience(all)
  • Toxicology

Cite this

Mumaw, C. L., Surace, M., Levesque, S., Kodavanti, U. P., Kodavanti, P. R. S., Royland, J. E., & Block, M. (Accepted/In press). Atypical microglial response to biodiesel exhaust in healthy and hypertensive rats. NeuroToxicology. https://doi.org/10.1016/j.neuro.2016.10.012

Atypical microglial response to biodiesel exhaust in healthy and hypertensive rats. / Mumaw, Christen L.; Surace, Michael; Levesque, Shannon; Kodavanti, Urmila P.; Kodavanti, Prasada Rao S; Royland, Joyce E.; Block, Michelle.

In: NeuroToxicology, 01.06.2016.

Research output: Contribution to journalArticle

Mumaw CL, Surace M, Levesque S, Kodavanti UP, Kodavanti PRS, Royland JE et al. Atypical microglial response to biodiesel exhaust in healthy and hypertensive rats. NeuroToxicology. 2016 Jun 1. https://doi.org/10.1016/j.neuro.2016.10.012
Mumaw, Christen L. ; Surace, Michael ; Levesque, Shannon ; Kodavanti, Urmila P. ; Kodavanti, Prasada Rao S ; Royland, Joyce E. ; Block, Michelle. / Atypical microglial response to biodiesel exhaust in healthy and hypertensive rats. In: NeuroToxicology. 2016.
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