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Published on: October 14, 2021
Dopamine agonists in dihydropteridine reductase deficiency
Francesco Porta1, Alessandro Mussa, Daniela Concolino
1Department of Pediatrics, University of Torino, Italy. porta.franc@gmail.com
Molecular Genetics and Metabolism
|February 14, 2012
Summary
Pramipexole, a dopamine agonist, effectively treats dihydropteridine reductase (DHPR) deficiency, a tetrahydrobiopterin (BH4) metabolism disorder. It reduces L-dopa dosage and improves patient symptoms and biochemical markers.
Area of Science:
- Neuroscience
- Metabolic Disorders
- Pharmacology
Background:
- Severe tetrahydrobiopterin (BH4) metabolism disorders traditionally use replacement therapy with BH4, 5-hydroxytryptophan, and L-dopa.
- L-dopa therapy presents challenges, including short half-life and adverse effects, necessitating L-dopa-sparing strategies.
Observation:
- Two male patients (7 and 22 years) with dihydropteridine reductase (DHPR) deficiency exhibited residual dopamine deficiency symptoms and L-dopa therapy complications.
- Patients experienced movement and behavioral disabilities and fluctuating hyperprolactinemia.
Findings:
- Pramipexole administration led to a significant reduction in L-dopa dosage (-58%) in one patient and complete cessation in the other.
- Both patients showed marked clinical improvement, with reduced Unified Parkinson's Disease Rating Scale (UPDRS) scores and normalized diurnal prolactin profiles.
Implications:
- Dopamine agonists like pramipexole demonstrate potential in improving or replacing L-dopa therapy for BH4 metabolism disorders.
- This finding offers a promising therapeutic avenue for managing complex neurological and metabolic conditions.
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