Blackberry Flavonoid Absorption and Effects on Intestinal Bacteria

Intestinal bacteria can metabolize unabsorbed polyphenols (plant compounds) to produce smaller molecules which may impact health. In addition, evidence suggests that this process may be affected by body fatness. This study aims to investigate absorption of blackberry polyphenols, their impact on intestinal bacteria, polyphenol metabolites formed by intestinal bacteria, and how these processes differ for obese and lean individuals. It is hypothesized that polyphenol absorption and metabolism will differ between obese and lean individuals and that differences in intestinal microbiota may play a role.

Study Overview

• Status: Completed
• Conditions: Metabolic Syndrome
• Intervention / Treatment: Other: Blackberries; Other: Control

• Study Type: Interventional
• Enrollment (Actual): 46
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Maryland
    • Beltsville, Maryland, United States, 20906
      • Beltsville Human Nutrition Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 25 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• 25-75 years old

Exclusion Criteria:

• Use of blood-thinning medications such as Coumadin (warfarin), Dicumarol (dicumarol), or Miradon (anisindione)
• Presence of any gastrointestinal disease, metabolic disease, or malabsorption syndromes that may interfere with the study goals
• Have been pregnant during the previous 12 months, are currently pregnant or lactating, or plan to become pregnant during the study
• Type 2 diabetes requiring the use of oral antidiabetic agents or insulin
• Fasting triglycerides greater than 300 mg/dL
• Fasting glucose greater than 126 mg/dL
• History of eating disorders or other dietary patterns which are not consistent with the dietary intervention (e.g., vegetarians, very low fat diets, high protein diets)
• Use of prescription or over-the-counter antiobesity medications or supplements (e.g., phenylpropanolamine, ephedrine, caffeine) during and for at least 6 months prior to the start of the study or a history of a surgical intervention for obesity
• Active cardiovascular disease (such as a heart attack or procedure within the past three months or participation in a cardiac rehabilitation program within the last three months, stroke, or history/treatment for transient ischemic attacks in the past three months, or documented history of pulmonary embolus in the past six months).
• Use of any tobacco products in past 3 months
• Unwillingness to abstain from herbal supplements for two weeks prior to the study and during the study
• Known (self-reported) allergy or adverse reaction to blackberries or other study foods
• Unable or unwilling to give informed consent or communicate with study staff
• Self-report of alcohol or substance abuse within the past twelve months and/or current acute treatment or rehabilitation program for these problems (Long-term participation in Alcoholics Anonymous is not an exclusion)
• Other medical, psychiatric, or behavioral factors that in the judgment of the Principal Investigator may interfere with study participation or the ability to follow the intervention protocol

Study Plan

How is the study designed?

Design Details

• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Control-Blackberry; Participants will receive a controlled diet with the control food (jello) first and then cross over to the controlled diet with blackberries.	Other: Blackberries; Participants will receive blackberries as part of a controlled diet.; Other: Control; Participants will receive a control food (jello) as part of a controlled diet.
Experimental: Blackberry-Control; Participants will receive a controlled diet with blackberries first and then cross over to the controlled diet with the control food (jello).	Other: Blackberries; Participants will receive blackberries as part of a controlled diet.; Other: Control; Participants will receive a control food (jello) as part of a controlled diet.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in fecal microbiota	Feces will be analyzed for bacterial typing at 0 and 4 weeks of each diet period.	0 weeks, 4 weeks

Secondary Outcome Measures

Outcome Measure	Time Frame
Change in blackberry nutrients & metabolites	0, 30, 60, 90, 120, 150, 180, 240, 300, 360, and 420 minutes

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in gene expression	Gene expression in whole blood will be evaluated at the beginning and end of each diet period, through global gene expression using the Affymetrix platform. Changes in specific genes observed with global gene expression technology will be confirmed through RT-PCR.	0 weeks, 4 weeks
Change in metabolomics	Blood, urine, and feces will be analyzed by a technique called metabolomics, which is a broad sampling of metabolites.	0 weeks, 4 weeks
Change in biomarkers of cancer	Biomarkers of cancer risk such as oxidative stress and inflammatory markers will be analyzed at the beginning and end of each diet period.	0 weeks, 4 weeks
Change in lipopolysaccharide	Lipopolysaccharide will be measured in the blood as a measure of gut leakiness.	0 weeks, 4 weeks

Collaborators and Investigators

• Sponsor: Janet Novotny
• Collaborators: National Cancer Institute (NCI)
• Investigators: Principal Investigator: Janet A Novotny, Ph.D., USDA Beltsville Human Nutrition Research Center

Study record dates

Study Major Dates

• Study Start: September 1, 2013
• Primary Completion (Actual): April 1, 2014
• Study Completion (Actual): April 1, 2014

Study Registration Dates

• First Submitted: September 12, 2013
• First Submitted That Met QC Criteria: September 12, 2013
• First Posted (Estimate): September 17, 2013

Study Record Updates

• Last Update Posted (Estimate): July 22, 2014
• Last Update Submitted That Met QC Criteria: July 21, 2014
• Last Verified: July 1, 2014

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Insulin Resistance; Hyperinsulinism; Metabolic Syndrome
• Other Study ID Numbers: HS40

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No