Exposure to Polycyclic Aromatic Hydrocarbons, Plasma Cytokines, and Heart Rate Variability

Area of Science:

• Environmental Health
• Cardiovascular Physiology
• Biomarkers

Background:

• Epidemiological studies suggest links between polycyclic aromatic hydrocarbons (PAHs) and heart rate variability (HRV).
• The role of plasma cytokines in mediating PAH-associated HRV changes remains under-explored.
• Coke-oven workers represent an occupational group with potential for significant PAH exposure.

Purpose of the Study:

• To investigate the association between PAH exposure and plasma cytokine profiles.
• To examine the relationship between identified cytokines and heart rate variability (HRV).
• To explore potential mediating roles of cytokines in PAH-induced HRV alterations.

Main Methods:

• Discovery stage: Human Cytokine Antibody Arrays used to compare 280 plasma cytokines in 8 coke-oven workers versus 16 controls.
• Validation stage: Enzyme-linked immunosorbent assays (ELISAs) used to validate 4 selected cytokines in 489 coke-oven workers.
• Statistical analyses assessed associations between hydroxylated PAHs (OH-PAHs), cytokines (BDNF, ALCAM, CRP), and HRV.

Main Results:

• 19 cytokines showed significant differential expression between exposed workers and controls.
• OH-PAHs inversely correlated with brain-derived neurotrophic factor (BDNF) and positively with activated leukocyte cell adhesion molecule (ALCAM) and C-reactive protein (CRP).
• Increased BDNF and CRP levels were associated with decreased HRV, suggesting a mediating role.

Conclusions:

• PAH exposure is associated with altered plasma cytokine levels in coke-oven workers.
• Elevated cytokine levels correlate with reduced heart rate variability (HRV).
• Further human studies are needed to elucidate mechanisms linking PAH exposure, cytokines, and cardiovascular health.