TRPV1 Ile585Val polymorphism modulates acute blood-pressure response to traffic-related air pollution exposure

Exposure to traffic-related air pollutants (TRAPs) has been shown to increase the risk of cardiovascular disease; however, variability in individual responses remains incompletely understood. In this randomized, double-blind, crossover study, we evaluated the acute cardiovascular effects of TRAP exposure in 40 healthy, non-smoking adults and explored potential inter-individual variability related to the TRPV1 rs8065080 polymorphism, a candidate single-nucleotide polymorphism (SNP, a common variation at a single position in the DNA sequence). During a 2-h roadside exposure, participants wore powered air-purifying respirators equipped with either a particulate matter (PM) filter, a PM and volatile organic compounds filter, or a sham filter. All participants underwent three exposures to random filtration modes, separated by at least 2-week washout periods. Both participants and researchers were blinded to the type of filter in their PAPR. Ambulatory BP and heart rate (HR) were monitored throughout the exposures and 6 h following each exposure. Compared to the sham filter, PM filtration reduced the elevation of systolic BP (peak ΔSBP: -3.9 mmHg at 1-2 h post-exposure) and the decrease of HR (peak ΔHR: +5.5 bpm at 4-5 h post-exposure). Genotype-stratified analyses suggested potential differences in response patterns across TRPV1 rs8065080 variants, with more pronounced effects observed among participants with the C/C genotype; however, these findings should be interpreted as exploratory. Overall, these results support an acute effect of TRAP exposure on cardiovascular responses under real-world conditions and suggest potential inter-individual variability that warrants further investigation.