Phe for Me? A Precision Nutrition Clinical Trial of Metabolic, Cardiovascular, and Neurocognitive Responses to Phenylalanine Among Carriers and Non-carriers of PKU
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- University of Guelph
- Enrollment
- 56
- Locations
- 1
- Primary Endpoint
- Stop Signal Reaction Time
Study Overview
Brief Summary
This is a clinical intervention study of PKU carriers (cases) and non-carriers (controls). Upon completing the informed consent process, participants will complete baseline measures of chronic mental health prior to the intervention (PHQ-9, GAD-7, BIS-11). Participants will attend the Human Nutraceutical Research Unit (HNRU) at the University of Guelph, fasted, and first undergo baseline measures of cognition and acute mental health (mood) and provide samples or saliva, urine and dried blood spots to evaluate phenylalanine (Phe), tyrosine (Tyr) and their metabolites (PAH pathway functioning) as well as for genetic testing of the PAH gene. Participants will also complete a brief questionnaire which will include age, sex, ethnicity, income, weight and height (measured using a stadiometer and calibrated weigh scale), and confirmation that participants arrived to the lab fasted (i.e. have only had water to drink and no other foods/ beverages prior to analyses). Blood pressure and heart rate will also be measured at baseline.
Following baseline tests, participants will consume a pure L-Phe supplement dosed at 100 mg/kg mixed with 125 mL of water and 125mL of orange juice. Blood pressure and heart rate will be repeated at 1-hour post-L-Phe consumption. Two-hours postprandial, participants will repeat the cognitive tests and acute mental health (mood) assessment, blood pressure and heart rate measurement and provide follow-up saliva, urine and dried blood spot samples. Participants will also be asked to report any side effects they experienced with the L-Phe consumption.
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Other
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to — (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Carrier or non-carrier of PKU
- •At least 18 Years of age
- •Comfortable fasting the morning of the study (no food or drink other than water)
Exclusion Criteria
- •Diagnosed with: PKU, severe neurodegenerative conditions affecting cognition (e.g. Alzheimer's, Parkinson's, dementia), melanoma, hypertension, liver disease and/or kidney disease
- •Diagnosed with hypertension or hypotension
- •Taking a monoamine oxidase inhibitor anti-depressant
- •Pregnant or breastfeeding
- •Orange/citrus allergy or intolerance
- •Body weight 150 kg or greater
- •History of fainting during blood sampling
Arms & Interventions
Genetic Carriers and Non-Carriers of PKU
Intervention: L-Phenylalanine (Dietary Supplement)
Outcomes
Primary Outcomes
Stop Signal Reaction Time
Time Frame: Change from baseline to 2-hours post L-Phe supplementation
Response Inhibition
Secondary Outcomes
- Working Memory(Change from baseline to 2-hours post L-Phe supplementation)
- Tyrosine Levels(Change from baseline to 2-hours post L-Phe supplementation)
- Tyrosine Metabolites(Change from baseline to 2-hours post L-Phe supplementation)
- Mood(Change from baseline to 2-hours post L-Phe supplementation)
- Individual Coefficient of Variance (Variability in Reaction Time)(Change from baseline to 2-hours post L-Phe supplementation)
- Phenylalanine Levels(Change from baseline to 2-hours post L-Phe supplementation)
- Phenylalanine Metabolites(Change from baseline to 2-hours post L-Phe supplementation)
- Blood Pressure(Change from baseline to 1-hour and 2-hours post L-Phe supplementation)
- Heart rate(Change from baseline to 1-hour and 2-hours post L-Phe supplementation)
- Side Effects Following L-Phe Consumption(0-3 hours post L-Phe consumption)
Investigators
Justine Keathley
Assistant Professor
University of Guelph