Metabolic Availability of Tryptophan From White Maize

Not Applicable

Completed

• Conditions: Healthy
• Interventions: Other: Tryptophan

• Registration Number: NCT02402179
• Lead Sponsor: The Hospital for Sick Children

Brief Summary

Our objective is to determine the metabolic availability of Tryptophan in white maize using the indicator amino acid oxidation (IAAO) technique in adult men.

Detailed Description

Our objective is to determine the metabolic availability of Tryptophan in white maize. Seven young, healthy, male adults will receive graded levels (13.2, 26.4, 39.7, 52.9) of tryptophan requirement of 3.78 mg/kg/d as a crystalline amino acid (AA) mixture and a porridge of white cornmeal protein respectively.

Study Timeline

• Study Start: 2015-03
• Study First Submitted: 2015-03-19
• Study First Submitted QC: 2015-03-24
• Study First Posted: 2015-03-30
• Primary Completion: 2016-04
• Study Completion: 2016-05
• Status Verified: 2016-11
• Last Update Submitted: 2016-11-11
• Last Update Posted: 2016-11-15

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 7

Inclusion Criteria

• Healthy Adult males (20-49years old).
• Stable body weight
• Not on any medications that could affect protein and amino acid metabolism e.g. steroids.

Exclusion Criteria

• Recent weight loss within the last 3 months or on weight reducing diet.
• Unwillingness to participate or unable to tolerate the diet.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Tryptophan Amino Acid	Tryptophan	13.2, 26.4, 39.7, 52.9% of the mean tryptophan requirement of 3.78 mg/kg/d will be given to subjects.

Primary Outcome Measures

Name	Time	Method
Metabolic Availability of Tryptophan in Corn	9 hours	The quality of corn protein will be assessed by measuring the amount of its tryptophan available for protein synthesis (metabolic availability) using the slope ration method. The oxidation of the indicator amino acid phenylalanine will be measured in response to feeding graded intakes of tryptophan in a reference protein patterned after egg protein, and provided as a crystalline amino acid mixture. The pattern of oxidation of phylalanine in response to tryptophan provided in corn will be compared to the pattern of oxidation obtained from feeding the reference protein. On each study day, subjects will be fed 8 hourly meals and breath samples will be taken to measure the oxidation of phenylalanine. Samples will be collected at baseline after the fourth meal, and half hourly, beginning 2.5 hrs after the 5th meal. Breath samples will be analyzed for 13CO2 enrichment.

Trial Locations

Locations (1)

The Hospital for Sick Children; 🇨🇦 Toronto, Ontario, Canada