Bioefficacy of Beta-cryptoxanthin From Biofortified Maize (BIOCRYPT)

November 3, 2020 updated by: Newcastle University

Determination of Relative Bioavailability, Bioconversion and Bioefficacy of β-cryptoxanthin in Comparison to β-carotene From Biofortified Maize and External Stable Isotopes Using Compartmental Modelling

Since no quantitative information currently exists on how effectively the pro-vitamin A carotenoid (pVAC) β-cryptoxanthin (βCX) is converted to vitamin A (VA) in humans, this proof of principle study aims to compare the efficacy of both βCX and β-carotene (βC) to yield VA from biofortified maize. This data is critical before the breeding strategy for biofortified maize is directed towards high βCX-containing varieties in order to reduce VA deficiency in low-income countries.

Study Overview

Status

Unknown

Conditions

Intervention / Treatment

Detailed Description

Despite advances in reducing vitamin A (VA) deficiency worldwide, the prevalence remains highest and unchanged in sub-Saharan Africa and South Asia. Efficacy studies have demonstrated that increasing provitamin A carotenoid (pVAC) intake through consuming pVAC biofortified crops results in increased circulating β-carotene (βC) and VA body stores. It has also been shown that consumption of biofortified maize improved VA total body stores (TBS) as effectively as preformed VA supplementation, and significantly improved visual function in marginally VA deficient children. Despite the fact that βC is the primary focus of breeding programs for pVAC biofortified maize, there is convincing evidence that comparable dietary intakes of βC and β-cryptoxanthin (βCX) would result in 7-fold greater concentrations of βCX in blood.

The study is designed to determine for the first time the bioefficacy of βCX in comparison to βC in humans using state of the art isotope dilution techniques in combination with compartmental modelling. The project is conducted in two phases: Phase 1) the determination of best time points for assessment of βCX bioconversion, intestinal and postintestinal bioefficacy as well as quantifying TBS of VA in healthy volunteers; Phase 2) to test the bioefficacy of βCX and βC in maize by comparing a high βCX and low βC maize variety to a high βC and low βCX maize variety.

Phase 1 of the study involves 1 long study day (D0), where 10 ml of blood will be taken every 2 hours, via cannulation, for a total of 12 hours (70 ml of blood total). Subsequently, there are 13 followup visits on the mornings of Days 1, 2, 4, 7, 11, 14, 21, 28, 35, 49, 63, 77, and 91 where one 10 ml blood sample is taken.

Phase 2 of the study involves 2 whole days (D0 and D21) where approximately 10 ml of blood will be taken every 30-60 minutes, via cannulation, for a total of 8 hours (110 ml of blood total). Subsequently, there are 3 follow-up visits on the mornings of Days 1, 7, and 22 where one 10 ml blood sample is taken on each occasion.

In the mornings of the long/whole study days at either D0 or D21, participants will receive the muffin test meal before stable isotopes, dissolved in sunflower oil, are administered via oral pipette. At D0 or D21, the total dose of pVACs (labelled and unlabelled carotenoids) consumed in the muffin and oil is 3 mg alongside 0.4 mg of pre-formed VA.

Study Type

Interventional

Enrollment (Anticipated)

50

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

  • United Kingdom
    • Tyne & Wear
      • Newcastle Upon Tyne, Tyne & Wear, United Kingdom, NE2 4HH
        • Recruiting
        • Newcastle University
        • Contact:
        • Principal Investigator:
          • Georg Lietz, PhD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 40 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Healthy volunteers

Exclusion Criteria:

  • Females who are pregnant or lactating.
  • Not disclosing use and type of contraceptives.
  • Acute or chronic illness.
  • Concurrent participation in another study.
  • Unwillingness to discontinue personal nutritional supplements/vitamins.
  • Major food allergies/intolerance to study ingredients.
  • Previous history of anorexia or bulimia.
  • Inability to refrain from drinking alcohol when requested.
  • Fat mal-absorptive disorders or iron deficiency anaemia.
  • Dietary preformed vitamin A intake >600 µg/d.
  • BMI <20 and >29 kg/m2.
  • Smoking.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Sequential Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Phase 1
Determination absorption and bioconversion kinetics of [13C14]β-cryptoxanthin and provide external validation for single-sample prediction methods.
Dietary supplement: β-cryptoxanthin

Phase 1:

2.0mg of [13C14]β-cryptoxanthin, 1.0mg of [13C10]β-carotene and 0.4mg [2H6]retinyl acetate are given in sunflower oil at Time 0.

Phase 2:

1.5mg of [13C14]β-cryptoxanthin, 0.75mg of [13C10]β-carotene, 0.4mg [2H6]retinyl acetate are given in sunflower oil along with 0.25mg β-carotene and 0.5mg β-cryptoxanthin from maize are given at Time 0.

Then, 0.75mg of [13C14]β-cryptoxanthin, 1.5mg of [13C10]β-carotene, and 0.4mg [2H6]retinyl acetate are given in sunflower oil along with 0.5mg β-carotene and 0.25mg β-cryptoxanthin from maize are given on day 21.

Other Names:
  • β-carotene; retinyl acetate
Experimental: Phase 2
Test the bioefficacy of provitamin A carotenoids (pVACs) in maize by comparing a high β-cryptoxanthin:β-carotene (βCX:βC) variety to a low βCX:βC variety in combination with external [13C]-labelled pVACs.
Dietary supplement: β-cryptoxanthin

Phase 1:

2.0mg of [13C14]β-cryptoxanthin, 1.0mg of [13C10]β-carotene and 0.4mg [2H6]retinyl acetate are given in sunflower oil at Time 0.

Phase 2:

1.5mg of [13C14]β-cryptoxanthin, 0.75mg of [13C10]β-carotene, 0.4mg [2H6]retinyl acetate are given in sunflower oil along with 0.25mg β-carotene and 0.5mg β-cryptoxanthin from maize are given at Time 0.

Then, 0.75mg of [13C14]β-cryptoxanthin, 1.5mg of [13C10]β-carotene, and 0.4mg [2H6]retinyl acetate are given in sunflower oil along with 0.5mg β-carotene and 0.25mg β-cryptoxanthin from maize are given on day 21.

Other Names:
  • β-carotene; retinyl acetate

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Bioefficacy of β-cryptoxanthin
Time Frame: Phase 1 = 91 days. Phase 2 = 22 days.
Plasma concentrations of [13C14]-β-cryptoxanthin, [13C7]-retinyl esters, and [13C7]-retinol.
Phase 1 = 91 days. Phase 2 = 22 days.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Newcastle University

Collaborators

Penn State University
International Food Policy Research Institute

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

April 1, 2019

Primary Completion (Anticipated)

December 31, 2020

Study Completion (Anticipated)

December 31, 2020

Study Registration Dates

First Submitted

November 4, 2019

First Submitted That Met QC Criteria

November 4, 2019

First Posted (Actual)

November 6, 2019

Study Record Updates

Last Update Posted (Actual)

November 4, 2020

Last Update Submitted That Met QC Criteria

November 3, 2020

Last Verified

November 1, 2020

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • BH183438

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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Vitamin A Deficiency

Clinical Trials on β-cryptoxanthin

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Philippines

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

3
Subscribe