Evidence map›Paper›PMID 37633259›Full record

ArticleBrain : a journal of neurology2024

Review of the role of the endogenous opioid and melanocortin systems in the restless legs syndrome.

Arthur S Walters, Yuqing Li, Brian B Koo, William G Ondo, Leonard B Weinstock, David Champion, Lawrence B Afrin, Elias G Karroum, Kanika Bagai, Karen Spruyt

Open access · bronzeAbstract read
In one paragraph

Article in Brain : a journal of neurology, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.

0numbers the graph read from it
0cells of the map it votes in
14citing papers in PubMed
3.4field-weighted citation impact, top 7% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

14 citing papers in PubMed, 16 citations in OpenAlex.

  1. Observational
  2. Review
  3. The evolving treatment landscape of restless legs syndrome.Therapeutic advances in neurological disorders · 2026
    Review
  4. Review
  5. Review
  6. Review
  7. Article
  8. Article
  9. Evidence of Involvement of the Calcitonin Gene-Related Peptide in Restless Legs Syndrome.Movement disorders : official journal of the Movement Disorder Society · 2025
    Article
  10. Article
  11. Association between inflammatory cytokines and disease severity in restless legs syndrome.Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology · 2024
    Article
  12. Review
  13. Article
  14. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors at 9 institutions in 3 countries.

Arthur S WaltersSleep Division, Department of Neurology, Vanderbilt University Medical Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.ORCID 0000-0001-5143-7817
Yuqing LiNorman Fixel Institute for Neurological Diseases, Department of Neurology, College of Medicine, University of Florida, Gainesville, FL 32610, USA.
Brian B KooSleep Medicine Laboratory, VA Connecticut Health Care System, West Haven, CT 06516, USA.
William G OndoDepartment of Neurology, Methodist Hospital, Weill Cornell Medical School, Houston, TX 77030, USA.
Leonard B WeinstockDepartment of Internal Medicine, Washington University School of Medicine, St.Louis, MO 63130, USA.
David ChampionSydney Children's Hospital, Department of Pain Medicine, Randwick, NSW 2031, Australia.
Lawrence B AfrinHematology/Oncology, AIM Center for Personalized Medicine, Purchase, NY 10577, USA.
Elias G KarroumDepartment of Neurology and Rehabilitation Medicine, The George Washington University School of Medicine and Health Sciences, George Washington University, Washington, D.C. 20052, USA.
Kanika BagaiSleep Division, Department of Neurology, Vanderbilt University Medical Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
Karen SpruytUniversité Paris Cité, NeuroDiderot Inserm, Paris 75019, France.ORCID 0000-0002-2914-9074
Vanderbilt University Medical Center · USAbilities In Motion · USCornell University · USGeorge Washington University · USInserm · FRSydney Children's Hospital · AUUniversity of Florida · USVA Connecticut Healthcare System · USWashington University in St. Louis · US

Funding

Yale Clinical and Translational Science Award (U Component)UL1TR001863 · NCATS · YALE UNIVERSITY · PI John H. Krystal, LUCILA OHNO-MACHADO · 2016 to 2026
$102.9M
Supplement: Pathophysiology of DYT1 dystonia: Targeted Mouse ModelsR01NS129873 · NINDS · UNIVERSITY OF FLORIDA · PI YUQING LI · 2022 to 2026
$1.9M
Characterization of Meis1 mutant mice and implications in restless legs syndrome and other sleep disordersR21NS111498 · NINDS · UNIVERSITY OF FLORIDA · PI LI, YUQING · 2020 to 2021
$419k
Characterization of the involvement of the cerebellum in animal models of C9orf72 ALS/FTDR21NS118397 · NINDS · UNIVERSITY OF FLORIDA · PI LI, YUQING · 2020 to 2020
$419k
NCATS NIH HHS UL1 TR001863NINDS NIH HHS R01 NS129873NINDS NIH HHS R21 NS111498NINDS NIH HHS R21 NS118397
6 · The paper itself

Abstract

Restless legs syndrome (RLS) is responsive to opioid, dopaminergic and iron-based treatments. Receptor blocker studies in RLS patients suggest that the therapeutic efficacy of opioids is specific to the opioid receptor and mediated indirectly through the dopaminergic system. An RLS autopsy study reveals decreases in endogenous opioids, β-endorphin and perhaps Met-enkephalin in the thalamus of RLS patients. A total opioid receptor knock-out (mu, delta and kappa) and a mu-opioid receptor knock-out mouse model of RLS show circadian motor changes akin to RLS and, although both models show sensory changes, the mu-opioid receptor knock mouse shows circadian sensory changes closest to those seen in idiopathic RLS. Both models show changes in striatal dopamine, anaemia and low serum iron. However, only in the total receptor knock-out mouse do we see the decreases in serum ferritin that are normally found in RLS. There are also decreases in serum iron when wild-type mice are administered a mu-opioid receptor blocker. In addition, the mu-opioid receptor knock-out mouse also shows increases in striatal zinc paralleling similar changes in RLS. Adrenocorticotropic hormone and α-melanocyte stimulating hormone are derived from pro-opiomelanocortin as is β-endorphin. However, they cause RLS-like symptoms and periodic limb movements when injected intraventricularly into rats. These results collectively suggest that an endogenous opioid deficiency is pathogenetic to RLS and that an altered melanocortin system may be causal to RLS as well.

Indexed as

Analgesics, OpioidRestless Legs SyndromeAnimalsbeta-EndorphinDopamineHumansIronMelanocortinsMiceRatsAnalgesics, Opioidbeta-EndorphinDopamineIronMelanocortinsdopamineendogenous opioid systemironperiodic limb movements in sleep (PLMS)pro-opiomelanocortin (POMC)restless legs syndrome (RLS)

Identifiers

PMID37633259
PMCPMC10796165
OpenAlexW4386187502

What Socratic holds

Textmetadata
LicenceCC BY-NC
Read underepoch 390

Registered trials

None linked

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 Socratic graph.