Evaluation of oxidative stress and DNA damage in traffic policemen exposed to vehicle exhaust.

OBJECTIVE: We aimed to study the genotoxic effects in traffic police who are occupationally exposed due to higher free radical generation. METHODS: Ambient and breathing zone air samples were analyzed blood samples were collected for analysis of antioxidant enzymes Superoxide Dismutase (SOD), Glutathione Peroxidase (GPx) and free radicals - nitric oxide (NO) and malondialdehyde (MDA) levels using a spectrophotometer. DNA damage was measured with the comet assay. RESULTS: Higher levels of benzene (BZ), toluene (TOL), carbon monoxide (CO), benzo([a])pyrene (BaP) and sulfur dioxide (SO2) was observed in traffic police. Elevated levels of NO, MDA and comet tail length and lower SOD and GPx levels observed in traffic police. CONCLUSION: The studied biomarkers, related to oxidative stress and DNA damage positively correlated in traffic police exposed to environmental air pollutants.

Association of CYP1A1 Gene Polymorphism with Ischemic Stroke in South Indian Population.

Stroke is a major cause of morbidity and mortality worldwide. Genetic and environmental factors are involved in the pathogenesis of stroke. Hypertension, diabetes mellitus, and cigarette smoking are the major risk factors, and smoking doubles the risk of ischemic stroke. Smoking cessation decreased the risk for ischemic stroke. CYP1A1 is the phase I metabolizing enzyme which plays a key role in metabolic activation of polycyclic aromatic hydrocarbons which are present in cigarette smoke and considered carcinogenic. So far, the association of CYP1A1 gene polymorphism with stroke has not been investigated in Indian population. So, the study is taken up to evaluate the association of this polymorphism with ischemic stroke in a South Indian population. We genotyped 215 ischemic stroke patients and 162 age-matched controls using polymerase chain reaction-restriction fragment length polymorphism. Statistical analysis showed that CYP1A1 "CC" genotype is associated with five times increased risk of ischemic stroke (odds ratio (OR) = 5.14; 95% confidence interval (95% CI) = 1.14-23.14, p = 0.01), while "TT" (OR = 0.78, 95% CI = 0.51-1.19, p = 0.25) and "TC" (OR = 1.04, 95% CI = 0.67-1.60, p = 0.85) genotypes were nonsignificant with the increased risk of stroke. T and C allele frequencies in stroke were 76.5% and 23.5% as against 81.8% and 18.2% in control group, respectively, thus, suggesting no statistically significant differences in the T (OR = 0.72, 95% CI = 0.50-1.03, p = 0.07) and C (OR = 1.37, 95% CI = 0.96-1.97, p = 0.07) allele frequencies between the two groups. The distribution of CYP1A1 genotypes and allelic frequency within the stroke subtypes showed a significant association of CC genotype only in intracranial large artery atherosclerosis (OR = 5.21, 95% CI = 1.03-26.38, p = 0.02) while other subtypes did not show any association. Further analysis of CYP1A1 genotypes in patients and control subjects with smoking habit also showed a similar trend. Hence, we conclude that the CYP1A1 CC genotype is associated with the increased risk of ischemic stroke.