Acute Particulate Matter (PM₁₀) Exposure Selectively Triggers Behavioral Alterations in the Presymptomatic...

Area of Science:

• Neuroscience
• Environmental Health
• Immunology

Background:

• Multiple sclerosis (MS) involves central nervous system neuroinflammation and autoimmune responses.
• Air pollution, particularly particulate matter (PM), is linked to increased MS hospital admissions and exacerbated neuroinflammation.
• The impact of PM exposure on MS pathogenesis in susceptible individuals requires further investigation.

Purpose of the Study:

• To investigate the hypothesis that exposure to PM10 influences disease course and severity in a mouse model of MS with a predisposing background.
• To assess behavioral alterations in response to PM10 exposure in mice with experimental autoimmune encephalomyelitis (EAE).

Main Methods:

• Utilized the MOG35-55-induced experimental autoimmune encephalomyelitis (EAE) mouse model of MS.
• Administered short-term PM10 exposures before immunization or during the presymptomatic phase.
• Evaluated disease manifestation through clinical and neuropathological analyses.
• Assessed behavioral changes, including disinhibition, risk-taking, and novelty-seeking.

Main Results:

• Short-term PM10 exposure did not alter disease manifestation in EAE mice based on clinical and neuropathological assessments.
• Presymptomatic EAE mice, but not healthy mice, exhibited increased disinhibited, risk-taking, and novelty-seeking behaviors after PM10 exposure.
• These behavioral changes occurred before the onset of overt motor impairment.

Conclusions:

• Immunologically primed mice demonstrate a selective vulnerability to the behavioral effects of PM10 exposure.
• PM10 exposure can induce specific behavioral alterations in a preclinical MS model prior to motor symptom development.
• These findings highlight a potential link between air pollution and early-stage neurological and behavioral changes in MS susceptibility.