Effects of Exercise on Metabolic Parameters in Classical Homocystinuria

Study Overview
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Brief Summary
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The aim of this research project is to compare the effect of an aerobic exercise session in two different populations. Sampling biological material and collecting health-related personal data entails minimal risks and burdens. Participants will be asked to perform 30 minutes of an aerobic exercise on an ergocycle at a fixed power output to correspond to a moderate intensity for a sedentary population.

Detailed Description
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Background Among genetic causes of hyperhomocysteinemia, classical homocystinuria, manifest not only with vascular diseases but also with neurological symptoms. This is related to the higher homocysteine concentration of up to 150-300 μmol/l without treatment. Recently, some articles have shown that mild and temporary hyperhomocysteinemia may follow exercise in a healthy population. Investigators hypothesized that increase in homocysteine may be of greater importance in patients with classical homocystinuria where cystathionine beta-synthase deficiency prevents homocysteine metabolism. Objective To investigate the effect of an aerobic exercise in patients with classical homocystinuria on metabolic parameters compared to healthy controls.

Official Title
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Effects of Exercise on Metabolic Parameters in Treated Patients With Classical Homocystinuria: a Research Project on a Small Sample Size, Compared to Healthy Controls.

Conditions
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Homocystinuria

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria for subjects: Informed consent as documented by signature Confirmed biallelic mutation of cystathionine beta-synthase deficiency gene (homozygous or compound heterozygous) in an accredited Laboratory Continuation of their regular treatment under same dose (e.g. vitamin B6, B9 and B12, betaine) as prior to the study inclusion Inclusion Criteria for controls: - Healthy Exclusion Criteria: Any clinically instable concomitant disease Individuals with acute cardiac events, syncope, rhythm disturbances or unstable hypertension in the past 6 months Individuals with vitamins B9 or B12 deficiencies Homocysteine > 100 µmol/l (for subjects) Homocysteine > 20 µmol/l (for controls)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma homocysteine concentration | Change in homocysteine concentration after a 30 minute exercise at fixed wattage | -90 minutes before exercise to 24 hours after a 30 minute exercise | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dietary parameters | self-reporting daily food diary | During 3 days before and on the day of the exercise (day 1) | 
| Indirect calorimetry | Energy expenditure | -90 minutes before exercise to the end of exercise (+30 minutes) | 
| Plasma amino acid profile | Change in amino acid profile after a 30 minute exercise at fixed wattage | -90 minutes before exercise to 24hours after a 30 minute exercise | 
| Plasma Insulin concentration | Change in insulin concentration after a 30 minute exercise at fixed wattage | -90 minutes before exercise to 24 hours after a 30 minute exercise | 
| Plasma lactate concentration | Change in lactate concentration after a 30 minute exercise at fixed wattage | -90 minute before exercise to 24 hours after a 30 minute exercise | 
| Plasma glucagon concentration | Change in glucagon concentration after a 30 minute exercise at fixed wattage | -90 minute before exercise to 24 hours after a 30 minute exercise | 
| Plasma free fatty acids concentration | Change in free fatty acids concentration after a 30 minute exercise at fixed wattage | -90 minute before exercise to 24 hours after a 30 minute exercise | 
| Plasma ketone bodies concentration | Change in ketone bodies concentration after a 30 minute exercise at fixed wattage | -90 minute before exercise to 24 hours after a 30 minute exercise | 
| Plasma cortisol concentration | Change in cortisol concentration after a 30 minute exercise at fixed wattage | -90 minute before exercise to 24 hours after a 30 minute exercise | 
| Blood pressure | Change in blood pressure after a 30 minute exercise at fixed wattage | -90 min before exercise to 24 hours after a 30 minute exercise |