Risk of Pulmonary-Reproductive Dysfunctions, Inflammation and Oxidative DNA Damage in Exposure to Polycyclic Aromatic Hydrocarbon in Cigarette Smokers

Background: Exposure to cigarette smoke has been associated with pulmonary and reproductive dysfunctions; inflammatory response, oxidative stress and oxidative DNA damage induced by polycyclic aromatic hydrocarbons (PAHs) present in cigarette smoke have been implicated in the pathogenesis of these disorders. The peak expiratory flow rate (PEFR), a biomarker of inflammation and oxidative DNA damage (8-hydroxy-2-deoxyguanosine (8-OHdG), tumor necrosis factor alpha (TNF-α)), reproductive hormones (testosterone (TST), luteinizing hormone (LH), follicle stimulating hormone (FSH)) cotinine and urinary PAH metabolite (1-hydroxypyrene (1-HOP)) were estimated in male active smokers. Methods: One hundred men aged 20-47 years, comprising 50 active male smokers and 50 non-smokers, were randomly recruited into this comparative cross-sectional study. The PEFR was measured using a peak flow meter, serum levels of cotinine, FSH, LH, TST, TNF-α, and urine 8-OHdG by enzyme-linked immunosorbent assay and 1-HOP by high-performance liquid chromatography. Data analysis was done using a t-test and correlation analysis at p≤0.05. Results: Smokers had significantly higher cotinine (49.73±31.76 versus 0.51±0.69 ng/ml, p≤0.001), 8-OHdG (16.34±12.10 versus 5.79±2.14 ng/ml, p≤0.001) and lower PEFR (309.20±56.05 versus 452.80±45.76 L/min, p≤0.001) and LH (5.75±2.06 versus 6.97±2.79 mIU/ml, p=0.015) compared to non-smokers. Duration of exposure to cigarette smoke correlated positively with cotinine (r=0.937, p≤0.001) and 1-HOP (r=0.813, p≤0.001) while cotinine correlated positively with 1-HOP (r=0.863, p≤0.001) only in smokers. Conclusion: Reduced lung function and luteinizing hormone and concurrent increase in oxidative DNA damage associated with exposure to cigarette smoke may suggest the involvement of PAH-induced DNA damage in the development of pulmonary and reproductive impairment in smokers.