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Completed

NCT Number: NCT01944579

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.

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Key information

Conditions

Metabolic Syndrome Glucose Metabolism Disorders Hyperinsulinism Insulin Resistance Metabolic Diseases Nutritional and Metabolic Diseases

Age range

25 year–75 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Beltsville Human Nutrition Research Center

Beltsville, Maryland, 20906, United States

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

Blackberries

Other

Participants will receive blackberries as part of a controlled diet.

Control

Other

Participants will receive a control food (jello) as part of a controlled diet.

Primary outcomes

  1. Change in fecal microbiota

    Time frame: 0 weeks, 4 weeks

    Feces will be analyzed for bacterial typing at 0 and 4 weeks of each diet period.

Secondary outcomes

  1. Change in blackberry nutrients & metabolites

    Time frame: 0, 30, 60, 90, 120, 150, 180, 240, 300, 360, and 420 minutes

Other outcomes

  1. Change in gene expression

    Time frame: 0 weeks, 4 weeks

    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.

  2. Change in metabolomics

    Time frame: 0 weeks, 4 weeks

    Blood, urine, and feces will be analyzed by a technique called metabolomics, which is a broad sampling of metabolites.

  3. Change in biomarkers of cancer

    Time frame: 0 weeks, 4 weeks

    Biomarkers of cancer risk such as oxidative stress and inflammatory markers will be analyzed at the beginning and end of each diet period.

  4. Change in lipopolysaccharide

    Time frame: 0 weeks, 4 weeks

    Lipopolysaccharide will be measured in the blood as a measure of gut leakiness.

Sponsors and collaborators

Lead sponsor

Janet Novotny

Fed

Collaborators

  • National Cancer Institute (NCI)

Registry information

Important dates

Study start
2013
Primary completion
2014
Study completion
2014
First posted
Sep 17, 2013
Registry last updated
Jul 22, 2014

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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