glucobrassicin and 3-3--diindolylmethane

Lee W. Wattenberg, who spent his entire career at the University of Minnesota, was a true pioneer in the field of chemoprevention. This paper is a tribute to his groundbreaking research which uncovered the cancer prevention properties of many dietary compounds, including those discussed here in some detail-indole-3-carbinol and diindolylmethane. These compounds occur as glucosinolate conjugates in cruciferous vegetables and are released when one chews or otherwise macerates the vegetable. They have numerous beneficial effects including the ability to prevent cancer in laboratory animals treated with carcinogens. We review some of the early work on indole-3-carbinol and diindolylmethane which spurred subsequent studies on their efficacy and molecular mechanisms of prevention. We also present unique data on field conditions that affect levels of their glucosinolate precursors in vegetables and on the release of diindolylmethane in people who consume cruciferous vegetables.

Topics: Animals; Anticarcinogenic Agents; Benzo(a)pyrene; Biomarkers; Brassicaceae; Carcinogens; Cell Line, Tumor; Diet; Disease Models, Animal; Epigenesis, Genetic; Glucosinolates; Humans; Indoles; Lung; Neoplasms; Nitrosamines; Vegetables

Glucobrassicin in Brassica vegetables gives rise to indole-3-carbinol (I3C), a compound with potent anticancer effects in preclinical models. We previously showed that the urinary metabolite 3,3'-diindolylmethane (DIM) could discriminate between volunteers fed high and low doses of Brassica vegetables. However, the quantitative relationship between glucobrassicin exposure and urinary DIM level is unclear. We conducted a clinical trial to examine the hypotheses that a range of glucobrassicin exposure from Brassica vegetables is reflected in urinary DIM and that this effect plateaus. Forty-five subjects consumed vegetables, a mixture of brussels sprouts and/or cabbage, at one of seven discrete dose levels of glucobrassicin ranging from 25 to 500 μmol, once daily for 2 consecutive days. All urine was collected for 24 hours after each vegetable-eating session. Urinary DIM was measured using our published liquid chromatography-electrospray ionization-tandem mass spectrometry-selected reaction monitoring (LC/ESI-MS/MS-SRM) method. Urinary DIM excretion increased predictably with increasing glucobrassicin dose and plateaued between 200 and 300 μmol of glucobrassicin. The association between glucobrassicin dose and urinary DIM was strong and positive (R

Topics: Adult; Biomarkers; Brassica; Chromatography, Liquid; Diet; Glucosinolates; Humans; Indoles; Middle Aged; Tandem Mass Spectrometry; Young Adult

Brassica vegetable consumption may confer a protective effect against cancer, possibly attributable to their glucosinolates. Glucobrassicin is a predominant glucosinolate and is the precursor of indole-3-carbinol (I3C), a compound with anticancer effects. However, objective assessments of I3C uptake from Brassica vegetables have not been successful.. We conducted a randomized, crossover trial to test whether 3,3'-diindolylmethane (DIM, a metabolite of I3C) excreted in the urine after consumption of raw Brassica vegetables with divergent glucobrassicin concentrations is a marker of I3C uptake from such foods. Twenty-five subjects were fed 50 g of either raw "Jade Cross" Brussels sprouts (high glucobrassicin concentration) or "Blue Dynasty" cabbage (low glucobrassicin concentration) once daily for 3 days. All urine was collected for 24 hours after vegetable consumption each day. After a washout period, subjects crossed over to the alternate vegetable. Urinary DIM was measured using a novel liquid chromatography-electrospray ionization-tandem mass spectrometry-selected reaction monitoring (LC-ESI-MS/MS-SRM) method with [(2)H2]DIM as internal standard.. Urinary DIM was consistently and significantly higher after Brussels sprouts feeding than after cabbage feeding, as evidenced by an average difference of 8.73 pmol/mg creatinine (95% confidence interval, 5.36-12.10; P = 0.00002).. We have successfully quantified urinary DIM after uptake of I3C from food, and demonstrated that differences in glucobrassicin exposure are reflected in urinary DIM levels.. Our LC-ESI-MS/MS-SRM method and the results of our study indicate urinary DIM is a measure of I3C uptake from Brassica vegetables, a finding that can be utilized in prospective epidemiologic and chemoprevention studies.

Topics: Adult; Biomarkers; Brassica; Cross-Over Studies; Female; Glucosinolates; Humans; Indoles; Male; Middle Aged; Tandem Mass Spectrometry; Young Adult

The aim of the study was to investigate the effect of storage on the contents of glucosinolates (GLS) and their degradation products in a boiled white cabbage. A 24h storage at 4 °C resulted in a decrease in GLS content (20-40%, depending on the cooking time applied) in the edible parts. The most significant losses were observed for sinigrin (20-45%), and the least for glucobrassicin (12-32%). Storage had a diversified effect on GLS breakdown products (indole-3-acetonitrile, indole-3-carbinol, ascorbigen and 3,3'-diindolylmethane released from glucobrassicin and 4-methylsulfinylbutanenitrile released from glucoiberin) in the boiled cabbage. The increase in the content of indole-3-acetonitrile, especially considerable within the first 24h of storage (and a simultaneous decrease in glucobrassicin) clearly indicates that degradation of GLS may occur during storage or cooling to 4 °C.

Topics: Ascorbic Acid; Brassica; Drug Stability; Fermentation; Food Handling; Food Preservation; Glucosinolates; Hot Temperature; Indoles

The aim of the study was to investigate the effect of the pasteurization process on the content of ascorbigen, indole-3-carbinol, indole-3-acetonitrile, and 3,3'-diindolylmethane in fermented cabbage. Pasteurization was run at a temperature of 80 °C for 5-30 min. Significant changes were only observed in contents of ascorbigen and 3,3'-diindolylmethane. The total content of the compounds analyzed in cabbage pasteurized for 10-30 min was found to be decreased by ca. 20%, and the losses were due to thermal degradation of the predominating ascorbigen. Pasteurization was found not to exert any considerable effect on contents of indole-3-acetonitrile and indole-3-carbinol in cabbage nor did it affect contents of the compounds analyzed in juice.

Topics: Ascorbic Acid; Brassica; Fermentation; Glucosinolates; Hot Temperature; Indoles; Pasteurization