Modulation of aflatoxin biomarkers in human blood and urine by green tea polyphenols intervention.
To evaluate the efficacy of green tea polyphenols (GTPs) in modulating aflatoxin B(1) (AFB(1)) biomarkers, a total of 352 serum samples and 352 urine samples collected from a 3 month chemoprevention trial with 500 mg GTPs, 1000 mg GTPs and a placebo were measured for AFB(1)-albumin adducts (AFB-AA), aflatoxin M(1) (AFM(1)) and aflatoxin B(1)-mercapturic acid (AFB-NAC). Levels of AFB-AA at baseline were comparable for all three dose groups (P = 0.506). No significant differences were observed in AFB-AA levels in the placebo group over the 3 month period (P = 0.252). However, a significant reduction in AFB-AA levels was observed in the 500 mg group (P = 0.002). A marginally significant reduction in AFB-AA levels was also found in the 1000 mg group over the 3 month intervention period (P = 0.051). An analysis using a mixed-effects model indicated that the reduction in AFB-AA levels over time was dose and time dependent (dose-time interaction P = 0.049). There were no significant differences in median AFM(1) levels among the three study groups at the baseline (P = 0.832), 1 month (P = 0.188) and 3 months (P = 0.132) of the GTP intervention; however, reduction of 42 and 43% in median AFM(1) levels, as compared with the placebo, were found in 500 mg (P = 0.096) and 1000 mg (P = 0.072) groups at 3 months of the intervention. Significant elevations in median AFB-NAC levels and the ratio of AFB-NAC:AFM(1) were found in both 500 and 1000 mg groups compared with the placebo group at both 1 month (P < 0.001) and 3 months (P < 0.001) of GTPs intervention. These results demonstrate that GTPs effectively modulate AFB(1) metabolism and metabolic activation.
Tang
Lili
L
Department of Environmental Toxicology, The Institute of Environmental and Human Health, Texas Tech University, PO Box 41163, Lubbock, TX 79409-1163, USA.
Tang
Meng
M
Xu
Li
L
Luo
Haitao
H
Huang
Tianren
T
Yu
Jiahua
J
Zhang
Lisheng
L
Gao
Weimin
W
Cox
Stephen B
SB
Wang
Jia-Sheng
JS
D000328:Adult; D000348:Aflatoxins / Q000097:blood* / Q000494:pharmacology* / Q000652:urine*; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D015415:Biomarkers; D018890:Chemoprevention; D005260:Female; D005419:Flavonoids / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D008297:Male; D008954:Models, Biological; D010636:Phenols / Q000737:chemistry* / Q000494:pharmacology; D010919:Placebos; D059808:Polyphenols; D011863:Radioimmunoassay / Q000379:methods; D013662:Tea; D013997:Time Factors
D000348:Aflatoxins; D016588:Anticarcinogenic Agents; D015415:Biomarkers; D005419:Flavonoids; D010636:Phenols; D010919:Placebos; D059808:Polyphenols; D013662:Tea