RESUMO
In this study, we aimed to investigate the extent of genotoxic risk and the association between null GSTM1/GSTT1 and GSTP1 Ile105Val variants and cellular DNA damage, as measured by micronucleus (MN) assay in a group of agricultural workers from Denizli, Turkey. Peripheral blood samples were collected from 116 subjects, including 58 workers who were occupationally exposed to pesticides and 58 healthy unexposed controls. The MN frequencies of each individual were assessed by cytokinesis-blocked micronuclei assays on lymphocytes. Genotypes for different GST variants were determined using polymerase chain reaction-based methods. A significant 3.4-fold increase in MN frequency was observed in workers compared with the controls (p < 0.001). Among the GST genotypes, only the GSTM1 null genotype was found to be significantly associated with an increased MN frequency in workers (p = 0.01). Individuals with a concomitant null GSTM1/GSTT1 genotype demonstrated a significant (p = 0.01) increase in MN frequency compared with those with functional isozymes in the exposed worker group. The association of the GSTM1 null genotype with higher MN frequency suggests that it may be a modifier of genotoxic risk in individuals exposed to pesticides and may thus be a candidate susceptibility biomarker for human biomonitoring studies.
Assuntos
Fazendeiros , Glutationa Transferase/genética , Testes para Micronúcleos , Exposição Ocupacional/efeitos adversos , Praguicidas/toxicidade , Adulto , Estudos de Casos e Controles , Dano ao DNA , Monitoramento Ambiental , Feminino , Frequência do Gene , Marcadores Genéticos , Genótipo , Técnicas de Genotipagem , Glutationa S-Transferase pi/genética , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Masculino , Praguicidas/sangue , Turquia , Adulto JovemRESUMO
CONTEXT: Although humans are exposed to o-coumaric acid (OCA) in their diet, there is no available literature related to drug interaction and the carcinogen-activating potential of OCA in the HepG2 cell line. OBJECTIVE: This study was undertaken to determine the effects of OCA on the cytochrome P450 (CYP) 1A2, CYP2E1, CYP2C9, and CYP3A4 enzymes, which are primarily involved in carcinogen and drug metabolism. MATERIALS AND METHODS: The cytotoxicity of OCA in HepG2 cells was investigated by measuring the cleavage of WST-1. The protein and mRNA levels of CYPs were determined by western blotting and RT-PCR, respectively. RESULTS: The EC10, EC25, and EC50 values of OCA were calculated to be 1.84, 3.91 and 7.39 mM, respectively. A sublethal dose of 5 mM was used throughout this study. The CYP1A2 protein and mRNA levels were increased by 52 and 40% (p < 0.05), as were the CYP2E1 levels by 225 and 424%, respectively (p < 0.05). However, OCA treatment caused 52 and 60% decreases in the levels of CYP3A4 protein and mRNA (p < 0.05), respectively. In contrast to CYP3A4, the CYP2C9 protein and mRNA levels increased by 110 and 130%, respectively. DISCUSSION AND CONCLUSION: Co-administration of OCA with some drugs may lead to undesirable food-drug interactions due to modulatory effects on CYP isozymes involved in drug metabolism. Moreover, exposure to OCA may cause an increase in carcinogenicity and toxicity due to the induction of the CYP isozymes involved in chemical carcinogenesis. Therefore, serious precautions should be taken when using OCA as a supplement.
Assuntos
Antineoplásicos/farmacologia , Carcinógenos/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Ácidos Cumáricos/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Ativação Metabólica , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Sistema Enzimático do Citocromo P-450/genética , Relação Dose-Resposta a Droga , Interações Medicamentosas , Células Hep G2 , Humanos , Isoenzimas , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , RNA Mensageiro/metabolismo , Especificidade por SubstratoRESUMO
Among hydroxycinnamic acids, caffeic, ferulic and p-coumaric acids have received considerable attention due to their biological activities. However, studies related to the biological activities of o-coumaric acid (OCA) are limited. In this regard, this study was designed to determine the chemopreventive potential of OCA in human breast cancer cells (MCF-7). The EC50 value of OCA was found to be 4.95 mM and was used throughout the study. Caspase-3 protein and mRNA levels increased by 59% and 72%. Similarly, protein and mRNA levels of Bax were increased by 115% and 152%. However, OCA treatment caused 48% and 35% decreases in Bcl-2 protein and mRNA levels. Cyclin D1 and cyclin dependent kinase-2 protein and mRNA levels decreased significantly. Moreover, p53 protein and mRNA levels increased by 178% and 245%, respectively. In addition to p53, PTEN protein and mRNA levels were induced. Although, CYP1A1, CYP1A2 and CY2E1 mRNA levels increased, CYP3A4 and CYP2C9 mRNA levels decreased in response to OCA treatment. These results suggest that OCA demonstrates anticarcinogenic activity on MCF-7 cells by activating multiple pathways. However, it also has high carcinogen activating and drug interaction potential. Therefore, serious precautions must be taken before using OCA.
