Moderate Intensity Exercise and Phenylketonuria
| Status: | Completed |
|---|---|
| Conditions: | Endocrine |
| Therapuetic Areas: | Endocrinology |
| Healthy: | No |
| Age Range: | 14 - 17 |
| Updated: | 11/8/2014 |
| Start Date: | May 2013 |
| End Date: | June 2014 |
| Contact: | Joanna Helm |
| Email: | helmj@ohsu.edu |
| Phone: | 303-204-6444 |
The Effects of an Acute Bout of Moderate Intensity Exercise on Plasma Amino Acids in Subjects With Phenylketonuria
Phenylketonuria (PKU), an inherited genetic disorder, can cause irreversible brain damage,
declined executive function, and autistic tendencies unless a phenylalanine (Phe) restricted
diet is consistently maintained throughout life. Promoting anabolism, the uptake of free
amino acids from the extracellular space, is a key component to maintaining plasma
phenylalanine concentrations within treatment range among patients with PKU. Exercise
promotes muscle protein synthesis and anabolism, but the effect on blood phenylalanine
concentrations in patients with PKU has not been reported.
Our objective is to assess the impact of an acute bout of moderate intensity exercise on
protein oxidation and plasma amino acid concentrations, as a potential adjunctive therapy
for patients with PKU.
The investigators hypothesize that moderate intensity exercise decreases amino acid
oxidation, increases muscle protein synthesis, and promotes tissue uptake of essential amino
acids, thereby lowering plasma phenylalanine concentrations in patients with
Phenylketonuria.
declined executive function, and autistic tendencies unless a phenylalanine (Phe) restricted
diet is consistently maintained throughout life. Promoting anabolism, the uptake of free
amino acids from the extracellular space, is a key component to maintaining plasma
phenylalanine concentrations within treatment range among patients with PKU. Exercise
promotes muscle protein synthesis and anabolism, but the effect on blood phenylalanine
concentrations in patients with PKU has not been reported.
Our objective is to assess the impact of an acute bout of moderate intensity exercise on
protein oxidation and plasma amino acid concentrations, as a potential adjunctive therapy
for patients with PKU.
The investigators hypothesize that moderate intensity exercise decreases amino acid
oxidation, increases muscle protein synthesis, and promotes tissue uptake of essential amino
acids, thereby lowering plasma phenylalanine concentrations in patients with
Phenylketonuria.
The indicator amino acid oxidation technique utilizes a carbon labeled isotope (L-[13C])
tracer that is ingested orally and is measured in expired breath. This method is based on
the theory that if one essential amino acid is deficient, all other amino acids will be
oxidized until a break-point is reached and at that time all amino acids will be
incorporated into muscle protein synthesis. Using a randomized crossover design the
investigators plan to investigate the effects of an acute bout of moderate intensity
treadmill exercise versus sedentary activities on plasma amino acids in four subjects with
PKU. The long-term goal of this novel research is to determine if exercise could be used as
an adjunctive therapy to improve the management of plasma phenylalanine levels and promote a
normal, healthy quality of life among patients with PKU.
Patient Recruitment: Four post-pubertal participants ranging from 14-17 years of age with
classical phenylketonuria (PKU), treated at Oregon Health & Science University, will
participate in this pilot study. Participants will be recruited during their routine clinic
visit at Doernbecher Children's Hospital Metabolic clinic.
Study Design: This randomized crossover clinical trial will compare the effects of moderate
intensity exercise and sedentary activities on amino acid oxidation and plasma amino acid
pools using the indicator amino acid oxidation technique. Each participant will be studied
on two separate occasions over a one-month period.
tracer that is ingested orally and is measured in expired breath. This method is based on
the theory that if one essential amino acid is deficient, all other amino acids will be
oxidized until a break-point is reached and at that time all amino acids will be
incorporated into muscle protein synthesis. Using a randomized crossover design the
investigators plan to investigate the effects of an acute bout of moderate intensity
treadmill exercise versus sedentary activities on plasma amino acids in four subjects with
PKU. The long-term goal of this novel research is to determine if exercise could be used as
an adjunctive therapy to improve the management of plasma phenylalanine levels and promote a
normal, healthy quality of life among patients with PKU.
Patient Recruitment: Four post-pubertal participants ranging from 14-17 years of age with
classical phenylketonuria (PKU), treated at Oregon Health & Science University, will
participate in this pilot study. Participants will be recruited during their routine clinic
visit at Doernbecher Children's Hospital Metabolic clinic.
Study Design: This randomized crossover clinical trial will compare the effects of moderate
intensity exercise and sedentary activities on amino acid oxidation and plasma amino acid
pools using the indicator amino acid oxidation technique. Each participant will be studied
on two separate occasions over a one-month period.
Inclusion Criteria:
- plasma phenylalanine concentration of >1200 micromols at diagnosis
- treated by dietary phenylalanine restriction from early infancy
- willing to participate in this study
- stable BMI of 20-25 for the past 3 months
- currently in average to good physical fitness condition
- physically active 3-4 days per week
Exclusion Criteria:
- previously or are currently taking approved or experimental pharmacologic treatments
(i.e.: Biopterin (BH4), sapropterin dihydrochloride (Kuvan), Large Neutral Amino
Acids (LNAA), pegylated phenylalanine ammonia lyase (PEG-PAL))
- recent history of weight loss
- endocrine disorder
- pregnant
- anemic
- involved in any other study or research protocol
- participation in a current strength training or performance training regimen
We found this trial at
1
site
3181 Southwest Sam Jackson Park Road
Portland, Oregon 97239
Portland, Oregon 97239
503 494-8311
Oregon Health and Science University In 1887, the inaugural class of the University of Oregon...
Click here to add this to my saved trials
