Metabolic Processes in Adults and Adolescents With Autism Spectrum Disorder

NCT ID: NCT02733120

Last Updated: 2025-09-30

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 40 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2015-12-03
• Study Completion Date: 2017-10-30

Brief Summary

The objective of this study is to gain preliminary information and knowledge on metabolic profile in ASD. The benefit of this study will be to expand our insight of the potential relationship in metabolic processes and neuropsychological functions in ASD. For example, based on the obtained data of the study we can determine whether there is a link between the tryptophan pathway and cognitive functions in autism. The project is based on a systematic and multidisciplinary approach using tracers for delineating the mechanism by which the metabolism of amino acids like TRP is involved in affective and cognitive functions in ASD. Using an innovative approach to the evaluation of amino acids has not been used in adults with ASD. In addition, the obtained data of the study holds promise to develop specific markers (metabolic and/or neuropsychological) for guiding the identification those individuals with increased risk of developing mood disturbances or cognitive impairment, and for predicting the therapeutic effect of a specific nutritional interventions in subjects with ASD.

Detailed Description

This study investigates the metabolic profile of different amino acids and cognitive functions in adults and adolescents with ASD in comparison with age- and gender-matched healthy young adults. The study involves 1 screening visit of approximately 2 hours and 1 study day of 5 hours

The objective is to explore changes in amino acids (e.g. TRP pathway) in ASD and evaluate the function of TRP in neuropsychological functions by using the technique of stable isotope and our newly developed 'single pulse method' with multiple amino acid and keto-acid isotopes.

The aim of this study is to determine the underlying mechanism by which the metabolism of amino acids such as TRP are involved in mood and cognitive functions in ADS.

Conditions

Autism Spectrum Disorder

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: SUPPORTIVE_CARE
• Blinding Strategy: NONE

Study Groups

Healthy matched controls

Study Day: The subject will arrive fasted. A catheter will be inserted in the arm for stable isotope infusion and blood sampling. The hand of the arm used for blood sampling will be placed in a thermostatically controlled warmed box that heats the air. Immediately after a baseline blood sample is taken, an infusion with stable isotopes will be administered by the research nurse. Stable isotopes are given to measure amino acid metabolism. Blood samples will be collected before and/or after infusion. Subjects will be asked to complete a list of questions regarding quality of life, mood and depression, diet.

Group Type: EXPERIMENTAL

stable isotope infusion

Intervention Type: OTHER

stable isotopes such as 15N2, TRP, 2H3-Leucine, L-\[2H3\]-3-Methylhistidine, 2H2-Glycine, 2-D-hydroxyproline, 1-13C-ketoisocaproic acid (KIC), L-\[Guanido-15N2\]-Arginine, L-\[ureido-13C-2H2\]-Citrulline), L-Glutamine-amide-15N, 1,2-13C2-L-Glutamic acid, 1,2-13C2Taurine, and 13C-Urea is given IV simultaneously

Adults with Autism Spectrum Disorder

The subject will arrive fasted. A catheter will be inserted in the arm for stable isotope infusion and blood sampling. The hand of the arm used for blood sampling will be placed in a thermostatically controlled warmed box that heats the air. Immediately after a baseline blood sample is taken, an infusion with stable isotopes will be administered by the research nurse. Stable isotopes are given to measure amino acid metabolism. Blood samples will be collected before and/or after infusion. Subjects will be asked to complete a list of questions regarding quality of life, mood and depression, diet.

Group Type: EXPERIMENTAL

stable isotope infusion

Intervention Type: OTHER

stable isotopes such as 15N2, TRP, 2H3-Leucine, L-\[2H3\]-3-Methylhistidine, 2H2-Glycine, 2-D-hydroxyproline, 1-13C-ketoisocaproic acid (KIC), L-\[Guanido-15N2\]-Arginine, L-\[ureido-13C-2H2\]-Citrulline), L-Glutamine-amide-15N, 1,2-13C2-L-Glutamic acid, 1,2-13C2Taurine, and 13C-Urea is given IV simultaneously

Interventions

stable isotope infusion

stable isotopes such as 15N2, TRP, 2H3-Leucine, L-\[2H3\]-3-Methylhistidine, 2H2-Glycine, 2-D-hydroxyproline, 1-13C-ketoisocaproic acid (KIC), L-\[Guanido-15N2\]-Arginine, L-\[ureido-13C-2H2\]-Citrulline), L-Glutamine-amide-15N, 1,2-13C2-L-Glutamic acid, 1,2-13C2Taurine, and 13C-Urea is given IV simultaneously

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Healthy male or female according to the investigator's or appointed staff's judgment
• Age 16 years or older
• Ability to walk, sit down and stand up independently
• Ability to lie in supine or elevated position for 4 hours
• Willingness and ability to comply with the protocol

• Healthy high functioning person diagnosed with autism spectrum disorder
• Age 16 years or older
• Ability to walk, sit down and stand up independently
• Ability to lie in supine or elevated position for 4 hours
• Willingness and ability to comply with the protocol

Exclusion Criteria

• Any condition that may interfere with the definition 'healthy subject' according to the investigator's judgment (for healthy group)
• Failure to give informed consent
• Established diagnosis of Insulin Dependent Diabetes Mellitus
• Metabolic diseases, including hepatic or renal disorders
• Presence of acute illness or metabolically unstable chronic illness
• Presence of fever within the last 3 days
• Pre-planned surgery of procedures that would interfere with the conduct of the study
• Any other condition according to the PI or study physician that would interfere with proper conduct of the study / safety of the patient
• Current alcohol or drug abuse
• Use of protein or amino acid containing nutritional supplements within 5 days prior to the study days
• Use of long-term oral corticosteroids or short course of oral cortico-steroids 4 weeks preceding first test day
• Body Mass Index of < 18.5 or ≥ 40 kg/m2
• Montreal Cognitive Assessment score of < 20

• Minimum Eligible Age: 16 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Texas A&M University

OTHER

Sponsor Role: lead

Responsible Party

Marielle PKJ Engelen, PhD

Associate Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Marielle Engelen, PhD

Role: PRINCIPAL_INVESTIGATOR

Texas A&M University

Locations

Texas A&M University-CTRAL

College Station, Texas, United States

Countries

United States

References

Wierzchowska-McNew RA, Engelen MPKJ, Thaden JJ, Ten Have GAM, Deutz NEP. Obesity- and sex-related metabolism of arginine and nitric oxide in adults. Am J Clin Nutr. 2022 Dec 19;116(6):1610-1620. doi: 10.1093/ajcn/nqac277.

Reference Type: DERIVED

PMID: 36166849 (View on PubMed)

Other Identifiers

2015-0542

Identifier Type: -

Identifier Source: org_study_id