GSTP1 Genetic Polymorphisms and Relations Between Environmental Lead Exposure and Nitric Oxide Production

Abstract

ISEE-344 Objective: Despite reduction in environmental lead exposure, it remains one of the leading health problems. Some experimental studies showed that lead exposure increases nitric oxide production. However, no previous study has examined whether lead exposure affects serum nitric oxide concentrations in human. The purpose of this study was to assess the effect of GSTP1 genetic susceptibility to nitric oxide production in relation to environmental lead exposure. Material and Methods: We recruited 279 healthy male university students. Whole blood lead concentrations were determined by atomic absorption spectrophotometer. Serum nitrite plus nitrate (NOx) levels were assayed by spectrophotometric method using a Griess reaction. GSTP1 Ile105Val genetic polymorphisms were identified by PCR-RFLP method. Results: The mean of blood lead and serum NOx concentrations was 2.66 ± 1.04 μg/dL (range, 0.34–10.47 μg/dL) and 33.8 ± 18.9 μM (range, 7.5–121.4 μM), respectively. Blood lead and serum NOx levels were not significantly different according to the age group, smoking, alcohol consumption status, and GSTP1 genotypes (P > 0.05). Blood lead levels were significantly correlated with serum NOx levels (r = 0.163, P = 0.006). In multiple regression analysis after controlling for age, body mass index, and smoking status, serum NOx levels were significantly related to the blood lead levels in the all study subjects (β = 0.214, P = 0.012). Regression coefficients of blood lead levels on serum NOx levels were higher in individuals with GSTP1 Ile/Ile genotypes (β = 0.389, P = 0.002) than those with GSTP1 Ile/Val or Val/Val genotypes (β = 0.039, P = 0.723). Conclusions: These data indicate that environmental low-level lead could induce nitric oxide production and GSTP1 genotypes might modulate the association between lead exposure and serum NOx concentrations.