Document Detail

Brassica vegetables increase and apiaceous vegetables decrease cytochrome P450 1A2 activity in humans: changes in caffeine metabolite ratios in response to controlled vegetable diets.
MedLine Citation:
PMID:  10837004     Owner:  NLM     Status:  MEDLINE    
Induction or inhibition of biotransformation enzymes, enzymes that activate or detoxify numerous xenobiotics, is one mechanism by which vegetables may alter cancer risk. Using a randomized crossover design, we examined the effect of various vegetable diets on cytochrome P450 (CYP) 1A2, N-acetyltransferase 2 (NAT2) and xanthine oxidase activity in humans. Men and women, non-smokers, on no medication and 20-40 years of age ate four 6-day controlled diets: basal (vegetable-free) and basal with three botanically defined vegetable groups. Enzyme activities were determined by measuring urinary caffeine metabolite ratios after a 200 mg caffeine dose on the last day of each feeding period. Mean CYP1A2 activity for 19 men and 17 women (least squares means adjusted for sex, GSTM1 genotype, urine volume and feeding period) with basal, brassica, allium and apiaceous vegetable diets differed significantly (P </=ISOdia</= 0. 0005) by diet, irrespective of the caffeine metabolite molar ratio used to describe CYP1A2 activity; brassica vegetables increased (P <0.04) and apiaceous vegetables decreased (P </=ISOdia</= 0.02) activity compared with the basal and allium diets. There was no effect of diet on NAT2 and xanthine oxidase activities and none of the subjects differed by GSTM1 genotype. These results demonstrate that while one vegetable subgroup induces human CYP1A2 activity, another subgroup inhibits it. This points to a complex association between consumption of a typical diet of various vegetables and biotransformation enzyme activities in humans, an association that may be difficult to interpret in observational studies.
J W Lampe; I B King; S Li; M T Grate; K V Barale; C Chen; Z Feng; J D Potter
Related Documents :
9597024 - Oxidative dna damage levels in blood from women at high risk for breast cancer are asso...
22771784 - Epigallocatechin gallate enhances biliary cholesterol secretion in healthy rats and low...
9250804 - Slimming diet and the development of acute leukemia: a possible relationship? report of...
3296944 - Nutritional aspects in oesophageal carcinogenesis (review).
15012904 - Effect of ascorbic acid and acute heat exposure on heat shock protein 70 expression by ...
22244444 - Oxysterols as non-genomic regulators of cholesterol homeostasis.
Publication Detail:
Type:  Clinical Trial; Controlled Clinical Trial; Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Carcinogenesis     Volume:  21     ISSN:  0143-3334     ISO Abbreviation:  Carcinogenesis     Publication Date:  2000 Jun 
Date Detail:
Created Date:  2000-08-03     Completed Date:  2000-08-03     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  8008055     Medline TA:  Carcinogenesis     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  1157-62     Citation Subset:  IM    
Cancer Prevention Research Program, Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA 98109-1024, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Caffeine / pharmacokinetics*
Cytochrome P-450 CYP1A2 / genetics,  metabolism*
Enzyme Activation
Glutathione Transferase / genetics
Grant Support
Reg. No./Substance:
58-08-2/Caffeine; EC P-450 CYP1A2; EC Transferase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Efficacy of potential chemopreventive agents on rat colon aberrant crypt formation and progression.
Next Document:  Genetic variants of myeloperoxidase and lung cancer risk.