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Plasma cholinesterase activity is influenced by interactive effect between omethoate exposure and CYP2E1
Tuanwei Wang1, Hui Zhang1, Lei Li2
1Department of Occupational Health and Occupational Disease, College of Public Health, Zhengzhou University, Zhengzhou, Henan, P.R. China.
Summary
Omethoate exposure significantly decreased cholinesterase activity in workers. Specific CYP2E1 gene variants, particularly the AA genotype at rs6413432, interacted with omethoate exposure, leading to a notable reduction in plasma cholinesterase levels.
Area of Science:
- Environmental Toxicology
- Occupational Health
- Pharmacogenetics
Background:
- Omethoate is an organophosphate pesticide known to inhibit cholinesterase activity.
- Genetic polymorphisms in metabolizing enzymes can influence individual susceptibility to pesticide toxicity.
- Understanding gene-environment interactions is crucial for assessing occupational health risks associated with pesticide exposure.
Purpose of the Study:
- To investigate the association between polymorphisms in metabolizing enzyme genes and omethoate-induced cholinesterase activity decrease.
- To analyze gene-environment interactions in workers exposed to omethoate.
- To identify specific genetic factors contributing to reduced cholinesterase levels after omethoate exposure.
Main Methods:
- Recruitment of 180 omethoate-exposed workers and 115 healthy controls.
- Measurement of cholinesterase activity in whole blood, erythrocytes, and plasma.
- Genotyping of six polymorphic loci (GSTT1, GSTM1, GSTP1, CYP2E1, PON2) using PCR-RFLP.
- Analysis of gene-environment interactions using generalized linear models.
Main Results:
- Cholinesterase activity was significantly lower in the omethoate-exposed group compared to controls.
- Plasma cholinesterase activity was lower in individuals with TT+AT genotypes of CYP2E1 rs6413432 compared to the AA genotype within the exposure group.
- A significant interaction was observed between the AA genotype of CYP2E1 rs6413432 and omethoate exposure, affecting plasma cholinesterase activity.
Conclusions:
- The decrease in plasma cholinesterase activity due to omethoate exposure is associated with the interaction between the AA genotype of CYP2E1 rs6413432 and omethoate exposure.
- CYP2E1 rs6413432 polymorphism plays a role in modulating the impact of omethoate on cholinesterase activity.
- This highlights the importance of considering genetic factors in occupational health surveillance for pesticide-exposed workers.
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