Acute Nutritional Ketosis in GSD IIIa

University Medical Center Groningen (UMCG)

Status: Completed

Conditions: Glycogen Storage Disease IIIA

Treatments: Other: physical exercise

Study type: Interventional

Funder types: Other

Identifiers

NCT03011203

NL59081.042.16

Details and patient eligibility

About

The investigators will study if acute nutritional ketosis in adult GSD IIIa patients can boost muscle mitochondrial function in vivo.

Full description

Glycogen Storage Disease type IIIa (GSD IIIa) is an inborn error of carbohydrate metabolism caused by impaired glycogen debranching enzyme (GDE) activity. The ageing GSD IIIa cohort shows that muscle involvement -despite dietary management- is a common disabling phenotype in adulthood. Currently, no specific therapy has been established for muscle problems in adult GSD IIIa patients.

However, it could be hypothesized that nutritional ketosis (NK) will be highly beneficial to patients. Amongst others, ketone bodies could take on the role of primary energy source in exercising muscle. Recently, acute NK in exercise was studied in humans. NK was found to enhance muscle mitochondrial function in athletes.

The investigators will study if acute NK in adult GSD IIIa patients can boost muscle mitochondrial function in vivo.

Enrollment: 6 patients

Sex: All

Ages: 18 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• GSD III confirmed with enzyme assay and/or AGL mutation analysis and GSD IIIa further specified as deficient debranching enzyme activity in muscle or clinical and/or biochemical signs of cardiac and/or skeletal muscular involvement.

Exclusion criteria

• contraindications for MRI studies (assessed by standardised questionnaire)
• inability to perform bicycle exercise.
• intercurrent illness which may influence exercise tolerance (anemia, musculoskeletal injury, or other undiagnosed illness under investigation).
• known coronary artery disease, positive history for angina or cardiomyopathy.
• insulin-dependent diabetes mellitus.
• loss of, or an inability to give informed consent.
• pregnancy or current breastfeeding.
• any other cause which in the opinion of the investigators, may affect the participant's ability to participate in the study

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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6 participants in 2 patient groups

Ketone-ester drink

Experimental group

Description:

Oral intake - physical exercise

Treatment:

Other: physical exercise

Carbohydrate drink

Active Comparator group

Description:

Oral intake - physical exercise

Treatment:

Other: physical exercise