Daily Consumption of Well-Cooked Broccoli May Affect Glucosinolate Metabolites and Inflammatory Biomarkers

The objectives of the study are 1) to determine the influence of daily consumption of well-cooked broccoli on plasma and urinary glucosinolate metabolites, and 2) to determine inflammatory marker changes consistent with decreased cancer risk.

Study Overview

• Status: Completed
• Conditions: Healthy Volunteers
• Intervention / Treatment: Other: Control Diet; Other: Base Diet with Broccoli

Detailed Description

Consumption of Brassica vegetables is inversely associated with incidence of several cancers, including cancer of the lung, stomach, liver, colon, rectum, breast, endometrium, and ovaries. Brassica vegetables are a good source of many nutrients, but the unique characteristic of Brassicas (Broccoli in particular) is their rich content of glucosinolates. Glucosinolates are sulfur-containing compounds that are converted to isothiocyanates (ITC) by an enzyme in the plant called myrosinase, which is released when the vesicles containing myrosinase are ruptured by chewing or cutting. The isothiocyanates are considered to be the active agent for cancer prevention. Some of the mechanisms by which isothiocyanates likely inhibit cancer include modulation of cytochrome P450 enzymes, induction of phase II enzymes, and apoptosis.

The aim of this study is to investigate how daily consumption of broccoli with myrosinase inactivated by cooking influences glucosinolate metabolism and absorption, and consequent regulation of inflammatory markers.

• Study Type: Interventional
• Enrollment (Actual): 18
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Maryland
    • Beltsville, Maryland, United States, 20705
      • USDA-ARS, Beltsville Human Nutrition Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 17 years to 66 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Non tobacco user
• Cancer Free
• Not currently taking glucosinolate/isothiocyanate containing supplements

Exclusion Criteria:

• Type 2 diabetes requiring the use of diabetes pills, insulin, or non-insulin shots
• Use of blood-thinning medications such as Coumadin (warfarin), Dicumarol, or Miradon (anisinidione)
• History of bariatric surgery or nutrient malabsorption disease
• Pregnant, lactating, or intending to become pregnant during the study period
• Crohn's disease or diverticulitis
• Suspected or known strictures, fistulas or physiological/mechanical GI obstruction
• Self-report of alcohol or substance abuse within the past 12 months and/or current acute treatment or rehabilitation program for these problems (long-term participation in Alcoholics Anonymous is not an exclusion)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Control Diet; Participants will receive a controlled diet (base diet), typical of an American diet, with 0 g/day of broccoli (control).	Other: Control Diet; Participants will receive a controlled diet with 0 g/d of broccoli. Meals will be prepared using traditional American foods with a macronutrient composition representative of a typical American diet.; Other Names: Base Diet
Active Comparator: Brassica Diet; Participants will receive a controlled diet with 100 g of broccoli at both breakfast and dinner daily.	Other: Base Diet with Broccoli; Participants will receive a controlled diet with 100 g of broccoli at both breakfast and dinner daily. Meals will be prepared using traditional American foods with a macronutrient composition representative of a typical American diet.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The change in glucosinolate metabolites will be measured in blood plasma and urine	To track the change of endogenous broccoli isothiocyanates in this crossover study, glucosinolate metabolites will be measured in both blood plasma and urine	At end of diet period 1 (week 3) and at the end of diet period 2 (week 12)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body composition will be determined by dual energy x-ray absorptiometry (DEXA)	Determine fat, lean, and bone mineral mass, and visceral fat deposition in our subjects	Day 0, just prior to beginning the controlled diet
The ability of fecal microbiota to metabolize glucosinolates will be determined	Fecal samples will be presented with glucoraphanin to determine the ability of fecal microbes to metabolize it	once per week during diet periods 1 and 2 (weeks 1, 2, 3, 10, 11, and 12)
Fecal microbiota will be analyzed for microbial DNA	Fecal microbial communities will be determined using DNA extracted from fecal samples	once at the beginning and end of diet periods 1 and 2 (weeks 1, 3, 10, and 12)
Markers of gut health will be analyzed in blood	Zonulin in blood serum will be measured by ELISA	once in the third week of diet periods 1 and 2 (weeks 3 and 12)
Markers of inflammation will be measured in blood	Cytokines and acute phase proteins will be measured in blood	at end of diet period 1 (week 3) and at end of diet period 2 (week 12)

Collaborators and Investigators

• Sponsor: USDA Beltsville Human Nutrition Research Center

Publications and helpful links

General Publications

• Charron CS, Vinyard BT, Jeffery EH, Ross SA, Seifried HE, Novotny JA. BMI Is Associated With Increased Plasma and Urine Appearance of Glucosinolate Metabolites After Consumption of Cooked Broccoli. Front Nutr. 2020 Sep 24;7:575092. doi: 10.3389/fnut.2020.575092. eCollection 2020.

Study record dates

Study Major Dates

• Study Start (Actual): February 27, 2017
• Primary Completion (Actual): May 19, 2017
• Study Completion (Actual): May 19, 2017

Study Registration Dates

• First Submitted: December 19, 2016
• First Submitted That Met QC Criteria: January 4, 2017
• First Posted (Estimate): January 6, 2017

Study Record Updates

• Last Update Posted (Actual): May 25, 2017
• Last Update Submitted That Met QC Criteria: May 23, 2017
• Last Verified: May 1, 2017

More Information

Terms related to this study

• Other Study ID Numbers: HS55

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No