Related Experiment Video
Updated: Sep 1, 2025
Optogenetic Manipulation of Neuronal Activity to Modulate Behavior in Freely Moving Mice
Published on: October 27, 2020
Microglia activation in the mPFC mediates anxiety-like behaviors caused by Staphylococcus aureus strain USA300
Jiao Zou1, Weilong Shang2, Ling Yang1
1Department of Military Cognitive Psychology, School of Psychology, Third Military Medical University (Army Medical University), Chongqing, China.
Introduction:
Staphylococcus aureus (S. aureus) is considered as one of the major causative agents of serious hospital- and community-acquired infections. Recent studies have reported that S. aureus infection induced neuroinflammation and was linked with some mental disorders. To evaluate the effects of S. aureus infection on abnormal behaviors, we conducted the present study.
Methods:
A S. aureus USA300-infected mouse model was established using bacterial suspension injection into tail vein. A series of behavioral tests were performed after USA300 infection. The expression of cytokines was detected in serum and mPFC. The number and some morphological parameters of microglia were also evaluated by immunofluorescence staining.
Results:
Anxiety-like behaviors, instead of locomotor activity impairment or depression-like behaviors, were observed in mice infected with S. aureus USA300 compared with control. S. aureus USA300 infection caused overexpression of IL-6, TNF-α, and IL-1β in serum, resulted in microglial over-activation and excessive release of proinflammatory cytokines in the mPFC. In addition, overexpression of TLR2 accompanied by increased GLS1 and p-STAT3 was observed in the mPFC of mice infected with S. aureus USA300.
Conclusion:
This study provides evidence that S. aureus USA300 infection can lead to neuroinflammation in the mPFC of mice, which may contribute to the development of anxiety.
Insights
Staphylococcus aureus (S. aureus) infection in mice induced anxiety-like behaviors. This was linked to neuroinflammation, characterized by microglial activation and cytokine release in the brain.
Area of Science:
- Neuroscience
- Immunology
- Infectious Diseases
Background:
- Staphylococcus aureus (S. aureus) is a significant cause of hospital and community infections.
- Emerging evidence links S. aureus infections to neuroinflammation and mental health disorders.
Purpose of the Study:
- To investigate the impact of S. aureus infection on animal behavior.
- To explore the underlying neuroinflammatory mechanisms.
Main Methods:
- Established a mouse model of S. aureus USA300 infection via intravenous injection.
- Conducted behavioral tests, measured cytokine expression in serum and the medial prefrontal cortex (mPFC), and assessed microglial activation using immunofluorescence.
Main Results:
- S. aureus USA300 infection induced anxiety-like behaviors but not locomotor or depression-like behaviors.
- Observed elevated levels of IL-6, TNF-α, and IL-1β in serum.
- Detected microglial over-activation, increased pro-inflammatory cytokines, TLR2, GLS1, and p-STAT3 in the mPFC.
Conclusions:
- S. aureus USA300 infection triggers neuroinflammation in the mouse mPFC.
- This neuroinflammation may play a role in the development of anxiety-related behaviors.
