ArticleNPJ Parkinson's disease2021
Peripheral decarboxylase inhibitors paradoxically induce aromatic L-amino acid decarboxylase.
Article in NPJ Parkinson's disease, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 17 papers.
What it found
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
17 citing papers in PubMed, 26 citations in OpenAlex.
- Serum aromatic l-amino acid decarboxylase activity as a biomarker for prodromal and manifest Parkinson's disease.EBioMedicine · 2026Article
- Parkinson's Disease: From Bench to Bedside-Advancements in Diagnosis and Therapeutics using Pharmacogenomic Approach.Current gene therapy · 2026Review
- Plasma neurofilament light chain as a predictor of multiple system atrophy in idiopathic REM sleep behavior disorder.Journal of neurology · 2025Article
- Review
- Increased plasma DOPA decarboxylase levels in Lewy body disorders are driven by dopaminergic treatment.Nature communications · 2025Article
- Role and mechanism of molecular hydrogen in the treatment of Parkinson's diseases.Frontiers in neuroscience · 2025Review
- DOPA-decarboxylase is elevated in CSF, but not plasma, in prodromal and de novo Parkinson's disease.Translational neurodegeneration · 2024Article
- Silencing Parkinson's risk allele Rit2 sex-specifically compromises motor function and dopamine neuron viability.NPJ Parkinson's disease · 2024Article
- Untargeted metabolomics reveal pathways associated with neuroprotective effect of oxyresveratrol in SH-SY5Y cells.Scientific reports · 2023Article
- Adopting the Rumsfeld approach to understanding the action of levodopa and apomorphine in Parkinson's disease.Journal of neural transmission (Vienna, Austria : 1996) · 2023Review
- Article
- An emerging biomarker for dopaminergic cell loss.Nature aging · 2023Article
- DOPA decarboxylase is an emerging biomarker for Parkinsonian disorders including preclinical Lewy body disease.Nature aging · 2023Article
- CSF proteome profiling reveals biomarkers to discriminate dementia with Lewy bodies from Alzheimer´s disease.Nature communications · 2023Article
- Nanotechnological Advances for Nose to Brain Delivery of Therapeutics to Improve the Parkinson Therapy.Current neuropharmacology · 2023Review
- Sex differences in carcinoid syndrome: A gap to be closed.Reviews in endocrine & metabolic disorders · 2022Review
- The novel P330L pathogenic variant of aromatic amino acid decarboxylase maps on the catalytic flexible loop underlying its crucial role.Cellular and molecular life sciences : CMLS · 2022Article
Corrections and comments
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Authors and funding
9 authors at 3 institutions in 3 countries.
Funding
Abstract
Peripheral decarboxylase inhibitors (PDIs) prevent conversion of levodopa to dopamine in the blood by the enzyme aromatic L-amino acid decarboxylase (AADC). Alterations in enzyme activity may contribute to the required higher dosages of levodopa observed in many patients with Parkinson's disease. We evaluated the effect of levodopa/PDI use on serum AADC enzyme activity. Serum AADC enzyme activity was evaluated in three independent cohorts of patients with Parkinson's disease or parkinsonism (n = 301) and compared between patients on levodopa/PDI vs. patients not on this medication. AADC enzyme activity was elevated in 62% of patients on levodopa/PDI treatment, compared to 19% of patients not on levodopa/PDI (median 90 mU/L vs. 50 mU/L, p < 0.001). Patients with elevated AADC activity had longer disease duration and higher doses of levodopa/PDI. These findings may implicate that peripheral AADC induction could underlie a waning effect of levodopa, necessitating dose increases to maintain a sustained therapeutic effect.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.