Abstract W P239: Exposure to Airborne Particulate Matter from Vehicular Exhaust Results in Progression of Brain Injury Following Experimental Stroke
Inflammation is believed to play an important role in the progression of acute stroke. Air pollution is a potent environmental source of inflammation and oxidative stress. We sought to examine the impact of inhalation of airborne particulate matter (PM) derived from urban traffic on the progression of brain injury following acute stroke. Urban PM was collected with a particle sampler situated near the CA-110 Freeway in Los Angeles. Collected aerosols represented a mix of fresh PM, predominantly from vehicular traffic. These samples were then distilled to pollutant nanoparticles (<200 nm) and re-aerosolized for administration to mice through exposure chambers. Adult mice were exposed to aerosolized PM (n=12) or filtered air (n=12) for forty-five cumulative hours and then underwent middle cerebral artery ischemia (35 minutes)/ reperfusion (I/R). Infarct volumes and neurological function were compared between mice exposed to PM and filtered air on postoperative day 1. Reperfusion was assessed by percent recovery of blood flow on laser Doppler flowmetry (LDF). Following cerebral I/R, mice exposed to PM demonstrated larger infarct volumes [20.6 ±6.4% (n=8) vs. 11.3 ±6.6% (n=9); p=0.018] and less favorable neurological scores [5.8 ±2.96 (n=12) vs. 3.2 ±2.4 (n=12); p=0.019] when compared to mice exposed to filtered air. Mortality was higher for the PM cohort (8.3% vs. 0%, p=ns) Further, LDF demonstrated decreased reperfusion in the cohort of mice exposed to PM (64 ±39%, n=10) when compared to those exposed to filtered air (86 ±24%, n=10, p=ns). This data establishes a detrimental effect of particulate matter in the setting of acute stroke and suggests a potential inflammatory mechanism of action.
Author Disclosures: Q. LIu: None. R. Radwanski: None. R. Babadjouni: None. P. Baumbacher: None. J. Russin: None. S. He: None. T. Morgan: None. C. Sioutas: None. C. Finch: None. W. Mack: Consultant/Advisory Board; Modest; Penumbra Inc- Member of DSMB for Thaerapy stroke and Liberty stent (aneurysm) trials.
- © 2015 by American Heart Association, Inc.