Identification of New Biomarkers of Banana and Tomato Intake
Condition: Biomarkers; Food Intake
Study type: Interventional

Summary: 
      The intake of fruits and vegetables has been associated to a lower risk of developing
      metabolic diseases and cancer. The intake of tomato has been proposed to decrease the risk of
      prostate cancer while the high content of pro-vitamine A carotenes in banana have shown to
      alleviate Vitamin A deficiency in different countries. Interestingly in spite of their
      popularity, there are no biomarkers of banana intake reported in the literature while
      lycopene is the most frequently used metabolite to indicate tomato consumption however, its
      limited specificity and between-subjects variation sets doubt of its accuracy. Therefore, the
      identification of novel biomarkers for both banana and tomato is of great value. Untargeted
      metabolomics, allows a holistic analysis of the food metabolome allowing a deeper inquiry in
      the metabolism of different compounds and the recognition of patterns and individual
      differences that may lead to new hypothesis and further research. Therefore, the aim of the
      present study is to identify biomarkers of acute intake of banana and tomato using an
      untargeted approach on urine serum of 12 volunteers that participated in a crossover,
      randomized, controlled study. Volunteers consumed three different test foods: 1) 240g of
      banana, 2) 300g of tomato and 3) Fresubin 2kcal as control. Serum and urine samples were
      collected in kinetics over 24h and processed to be analyzed using LC-QTof analysis. The
      metabolomics profiles are compared using univariate (ANOVA) and multivariate statistical
      methods (PCA, PLSDA). The identification of discriminant compounds was performed by tandem
      mass fragmentation with a high-resolution LTQ-Orbitrab Mass spectrometer and by an extensive
      inquiry of different online databases.
    

Detailed description: 
      The rise of metabolomics along with different platforms such as liquid chromatography mass
      spectrometers (LC-MS) have allowed the assessment of thousands of metabolites simultaneously
      in biological samples and the recognition of patterns that may constitute a fingerprint of
      the intake of different foods. Recent studies demonstrated the great potential of
      metabolomics to discover new biomarkers of intake in intervention and cohort studies.The
      diversity of compounds found in food metabolomics represents a major challenge and so in an
      international effort to improve dietary biomarkers identification and validation, the Food
      Biomarkers Alliance (FOODBALL) has been created. In this project, 22 institutions from 11
      different countries will collaborate in three main tasks: 1) Discovery of new dietary
      biomarker using a metabolomic approach, 2) systemic validation of existing and newly
      discovered biomarker to achieve a good coverage of food intake in different European
      populations and 3) exploring biological effects using biomarkers of intake
      (http://foodmetabolome.org/). With the latter, the necessity of building a chemical library
      that allows the use of standards for further identification arises. Along with FOODBALL, The
      Food Compound Exchange (FoodComEx) aims to improve the availability of analytical standards
      of biological compounds to achieve a better and easier biomarker identification
      (http://foodcomex.org/).

      As part of INRA collaboration to FOODBALL and FoodComEx, the present project attempts to
      identify biomarkers of banana and tomato intake, through the exploration of the serum and
      urine metabolome of 12 subjects who consumed these foods following a randomized, controlled,
      crossover design. The present study was comprised of 3 different intervention periods and a
      minimum of 3 days washout between interventions. The intervention periods were comprised of 2
      run in days, 1 intervention day and 1 post intervention day. In the first day of the run in
      period, subjects were instructed to avoid the intake of banana or tomato or any of their
      products; the day prior to the intervention volunteers were asked to avoid the intake of
      phytochemical rich foods and beverages such as wine, coffee, chocolate, tea, and other plant
      based foods including banana and tomato.In the morning of the intervention, day subjects
      arrived in fasting state to the research center at 7.30 am. Volunteers were randomly assigned
      to one of the three interventions, Fresubin ® 2kcal fiber, 240g of banana plus control drink,
      or 300g of tomato plus control drink plus 12g of refined sunflower oil. Throughout the
      intervention, subjects had free access to water, maximum 250ml of water per hour until 6
      hours after the intake of the test food.

      A trained phlebotomist placed a catheter on the subject's arm before the intake of the test
      foods to collect the baseline sample. Then four other samples were collected postprandially
      after 1h, 2h, 4h, and 6h. A total of 7 urine samples were collected. The first void of urine
      was collected by the subjects at home upon the morning of Day 3 and the rest of the samples
      after the intake of the test foods as follows: 0-1h, 1h-2h, 2h-4h, 4h-6h. The urine samples
      corresponding to 6h-12h and 12-24h interval were collected by volunteers at home until the
      morning after the intake of the food.

      After the 6h collection of blood, the peripheral catheter was removed and subjects had lunch
      composed of white bread and cooked pasta, then subjects were allowed to go home. Before
      leaving the Investigation center, participants were instructed to prepare a standardized
      dinner based on pan fried chicken with butter and boiled rice with salt. Volunteers were not
      allowed to eat or drink anything except water and the standardized dinner.

      On the morning of the post intervention day, subjects arrived in fasting state to the
      research center to give the 24h blood sample and deliver the 06-12h and 12-24h urine
      collection. Afterward, subjects were served breakfast at the research center and resumed
      their normal diet until the next run in days of the next intervention period.

      Urine samples and serum samples were aliquoted and stored at -80° C until analysis.
    

Intervention name(s): Banana Cavendish; Tomato; Fresubin ® 2kcal fiber neutral flavor
Intervention type(s): Other; Other; Other
Intervention description(s): 240g of fruit plus 150ml of control drink (Fresubin ® 2kcal fiber neutral flavor); 300g of raw tomato ("coeur de boeuf") with refined sunflower oil (12g) and 150ml of control drink (Fresubin ® 2kcal fiber neutral flavor).; 250 ml Fresubin ® 2kcal fiber neutral flavor
Other intervention name(s): Test Food; Test Food; Control
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: The present project is a randomized, controlled, crossover study with 12 subjects. A cross-over design has been selected as each subject can serve as his/her own control thereby minimizing variations. The intervention order was randomized. The study design does not allow blinding as intervention is the ingestion of different foods.In this study, we assessed the metabolomic profiles of human biofluids after consumption of two different foods: banana (240g peeled fruit) and tomato (300g fresh fruit) in order to identify novel biomarkers for each food. As a control diet, a high energy high protein drink, Fresubin ® 2kcal fiber (Fresinius kabi) was used. The study comprised three dietary interventions of 4 days each and a wash-out period no shorter than 3 days.
Masking: None (Open Label)
Primary purpose: Other
Keywords: biomarkers; diet; banana; tomato; urine; plasma; intake; exposure; metabolomics