Lycopene and Beta-carotene Metabolism in the Digestive Tract of Healthy Men
Condition: Digestion Chambers; Stability and Metabolism of Carotenoids and Vitamin E
Study type: Interventional

Summary: 
      Consumption of foods containing carotenoids, as well as vitamin E, have been associated with
      lower risk of developing a number of chronic diseases. While the parent compounds have
      largely been assumed to exert protective antioxidant effects, more recent work has suggested
      that metabolites may be bioactive. Very little attention has been given to the metabolism of
      these compounds during the digestive process. Our primary aim is to conduct a postprandial
      feeding study in healthy men to determine the stability of carotenoids and vitamin E during
      digestion, and to identify the primary metabolites produced in various compartments of the
      upper gastrointestinal tract and blood during digestion. Targeted metabolites will be
      identified and quantitated using high-performance liquid chromatography-tandem mass
      spectrometry methods previously developed. In addition, a non-targeted metabolomics approach
      will be used to identify non-predicted metabolites in the samples. A better understanding of
      carotenoid and vitamin E stability and metabolism during digestion will provide greater
      insight into how these compounds may confer protection against chronic disease.
    

Detailed description: 
      Consumption of foods containing the carotenoids lutein, lycopene, beta-carotene, as well as
      vitamin E, have been associated with lower risk of developing chronic diseases including
      cardiovascular disease, cancer, age related macular degeneration, and cognitive decline.
      While the parent compounds have largely been assumed to exert protective antioxidant effects,
      more recent work has suggested that metabolites may be bioactive. Very little attention has
      been given to the metabolism of these compounds during the digestive process. Our primariy
      aim is to conduct a postprandial feeding study in healthy men to determine the stability of
      carotenoids and vitamin E during digestion, and to identify the primary metabolites produced
      in the upper gastrointestinal tract during digestion. Subjects will be fed a meal containing
      either lutein,lycopene, deuterated beta-carotene, or deuterated vitamin E. Gastric and
      duodenal samples will be taken 5 hours post-meal consumption, while blood plasma and
      chylomicron fractions will be taken over 7 hours post-meal consumption. Targeted metabolites
      will be identified and quantitated using high-performance liquid chromatography-tandem mass
      spectrometry methods previously developed. In addition, a non-targeted metabolomics approach
      will be used to identify non-predicted metabolites in a subset of collected samples. Overall,
      this research will provide very original insight about carotenoid and vitamin E metabolites
      produced during the digestive process and their absorption by the human body. This
      information is essential to understand how these compounds may confer protection against
      chronic disease.
    

Intervention name(s): lycopene; beta-carotene; control
Intervention type(s): Other; Other; Other
Intervention description(s): A tomato oleoresin containing lycopene; 13C beta-carotene; emulsified liquid meal alone
Intervention MeSH terms: Beta Carotene; Lycopene; Carotenoids
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Basic Science
Keywords: carotenoids; vitamin E; digestion; stability; metabolism