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Biochemical Genetics 01/2011; 49(5-6):364-8. · 0.86 Impact Factor
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ABSTRACT: Polycyclic aromatic hydrocarbons (PAHs) are associated with an increased cancer risk. CYP1A1 and GSTs enzymes are important in metabolism of PAHs. Genetic polymorphisms of these enzymes are responsible for enzyme activity and concentration variation. The objectives of this study were to evaluate association of 1-OHP concentration with genetic polymorphisms of CYP1A1 and GSTs in Thai bus drivers. The results showed that 1-OHP levels in bus drivers were significantly higher than that in the control group. Significant difference in 1-OHP was found between smokers and non-smokers, in only bus drivers. Significantly increasing of 1-OHP levels were observed in bus drivers with CYP1A1 MspI and exon 7 variants. Whereas, bus drivers with GSTP1 Val and GSTM1 null genotypes showed decreasing in excretion of 1-OHP. No association between 1-OHP and polymorphisms of GSTT1 was found. This study indicated that 1-OHP concentrations were associated with exposure to air pollution, cigarette smoking and polymorphisms of CYP1A1, GSTM1 and GSTP1 genes.
Environmental toxicology and pharmacology. 01/2011; 31(1):160-4.
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ABSTRACT: Paraoxonase (PON1) plays an important role in mechanism of organophosphorus compound (OP) toxicity, as seen both in vitro and in vivo studies. Polymorphisms of PON1 gene at coding and promoter regions have also been to affect on the hydrolytic activity and PON1 level. The objectives of this study were to determine PON1 polymorphism and activity in an OP-exposed population and the effects on inhibition of cholinesterase activity. The studied population consisted of control (n=30) and exposed groups (n=90). All enzyme activities (AChE, BuChE, paraoxonase, arylesterase and diazonase) were measured once for control group and two periods of exposure for exposed group. Three polymorphisms of PON1 (Q192R, L55M and T-108C) were identified only in the exposed subjects. The results demonstrated that AChE activity in both high (345.5 microkat/gHb) and low exposure periods (496.9 microkat/gHb) of the exposed group were significantly different from control group (649.7 microkat/gHb, p<0.01). For BuChE activity, the exposed group also showed the statistically lower level in both periods (high exposure period: 62.17 microkat/L and low exposure period: 81.84 microkat/L) than those in the control group (93.35 microkat/L). Serum paraoxonase activity was significantly different among individual genotypes, RR>QR>RR, LL>LM and -108CC>-108CT>-108TT, but this was not found for those of arylesterase and diazonase activities. Q192R and L55M as well as Q192R and T-108C also presented substantial linkage disequilibrium. Further analysis was performed with haplotypes and various enzyme activities. AChE activity was not affected by haplotypes. Individuals with "211" haplotype showed significantly higher paraoxonase activity and BuChE activity than other haplotypes but not in diazonase activity. In conclusion, PON1 gene exhibited a wide variation in enzyme activities both within and between genotypes which implied insights of a potentially difference in sensitivity to OP toxicity.
Chemico-Biological Interactions 08/2007; 168(3):184-92. · 2.46 Impact Factor
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ABSTRACT: In this study the levels of cadmium and lead in blood and urine were measured by the method of graphite furnace atomic absorption spectrometry in 356 healthy, non-occupationally exposed individuals and the factors affecting the metal concentrations were investigated. The geometric means for cadmium in blood and urine were 0.98 microg/l (Cd-B) and 0.87 microg/gCr (Cd-U). The lead levels were 32.5 microg/l for blood (Pb-B) and 2.54 microg/gCr for urine (Pb-U). Men had significantly higher blood cadmium and lead levels than women whereas the urinary excretion rates of both metals were higher in women than men. Cigarette smoking was found to affect the levels of Cd-B, Cd-U, and Pb-B. Other factors like alcohol intake and place of residence also related to blood lead levels. Both blood and urine levels of cadmium and lead in this study group were within acceptable ranges for non-occupationally exposed populations and were decreased compared with the past. It is important to continue monitoring levels of these metals in order to prevent adverse health effects in the Thai population.
The Southeast Asian journal of tropical medicine and public health 04/2002; 33(1):180-7. · 0.60 Impact Factor
