ArticleThe Journal of clinical endocrinology and metabolism2015
Endogenous Opioid Mechanisms Are Implicated in Obesity and Weight Loss in Humans.
Article in The Journal of clinical endocrinology and metabolism, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 31 papers, 3 of them syntheses that pooled it.
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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
31 citing papers in PubMed, 3 syntheses or guidelines pooled it, 63 citations in OpenAlex.
- Brain dopamine receptor system is not altered in obesity: Bayesian and frequentist meta-analyses.Human brain mapping · 2023Pooled it
- Effects of bariatric surgery and dietary interventions for obesity on brain neurotransmitter systems and metabolism: A systematic review of positron emission tomography (PET) and single-photon emission computed tomography (SPECT) studies.Obesity reviews : an official journal of the International Association for the Study of Obesity · 2023Pooled it
- Effects of total diet replacement programs on mental well-being: A systematic review with meta-analyses.Obesity reviews : an official journal of the International Association for the Study of Obesity · 2022Pooled it
- μ Opioid Antagonist Naltrexone Partially Abolishes the Antidepressant Placebo Effect and Reduces Orbitofrontal Cortex Encoding of Reinforcement.Biological psychiatry. Cognitive neuroscience and neuroimaging · 2021Trial
- Metabolic syndrome reduces but does not eliminate the cardioprotective effect of adaptation to hypoxia: the link with changes in the opioid system.Pflugers Archiv : European journal of physiology · 2025Article
- Mechanisms of metabolic surgery effectiveness in obesity and type 2 diabetes: a puzzle with some known pieces.International journal of obesity (2005) · 2025Review
- Early Impact of Bariatric Surgery on Brain Functionality.Journal of metabolic and bariatric surgery · 2025Review
- Anorexia nervosa is associated with higher brain mu-opioid receptor availability.Molecular psychiatry · 2025Article
- Endogenous opioid receptors and the feast or famine of maladaptive feeding.Nature communications · 2025Review
- Investigation of [Scientific reports · 2024Article
- Article
- Opioid Analgesics after Bariatric Surgery: A Scoping Review to Evaluate Physiological Risk Factors for Opioid-Related Harm.Journal of clinical medicine · 2023Article
- Early Relationships of a Low-Energy Diet With Symptoms of Fibromyalgia.ACR open rheumatology · 2022Article
- μ-opioid receptor availability is associated with sex drive in human males.Cognitive, affective & behavioral neuroscience · 2022Article
- Cerebral μ-opioid and CBTranslational psychiatry · 2021Article
- Preoperative brain μ-opioid receptor availability predicts weight development following bariatric surgery in women.JCI insight · 2021Article
- Mesolimbic opioid-dopamine interaction is disrupted in obesity but recovered by weight loss following bariatric surgery.Translational psychiatry · 2021Article
- Lowered endogenous mu-opioid receptor availability in subclinical depression and anxiety.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2020Article
- Neuroimaging of Sex/Gender Differences in Obesity: A Review of Structure, Function, and Neurotransmission.Nutrients · 2020Review
- Sucrose intake lowers μ-opioid and dopamine D2/3 receptor availability in porcine brain.Scientific reports · 2019Article
Corrections and comments
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Authors and funding
5 authors at 3 institutions in 1 country.
Funding
Abstract
contextSuccessful long-term weight loss is challenging. Brain endogenous opioid systems regulate associated processes; however, their role in the maintenance of weight loss has not been adequately explored in humans.
objectiveIn a preliminary study, the objective was to assess central μ-opioid receptor (MOR) system involvement in eating behaviors and their relationship to long-term maintenance of weight loss.
designThis was a case-control study with follow-up of the treatment group at 1 year after intervention.
settingThe study was conducted at a tertiary care university medical center.
participantsLean healthy (n = 7) and chronically obese (n = 7) men matched for age and ethnicity participated in the study.
interventionsMOR availability measures were acquired with positron emission tomography and [(11)C]carfentanil. Lean healthy men were scanned twice under both fasted and fed conditions. Obese men were placed on a very low-calorie diet to achieve 15% weight loss from baseline weight and underwent two positron emission tomography scans before and two after weight loss, incorporating both fasted and fed states.
main outcome measuresBrain MOR availability and activation were measured by reductions in MOR availability (nondisplaceable binding potential) from the fed compared with the fasted-state scans.
resultsBaseline MOR nondisplaceable binding potential was reduced in obese compared with the lean and partially recovered obese after weight loss in regions that regulate homeostatic, hedonic, and emotional responses to feeding. Reductions in negative affect and feeding-induced MOR system activation in the right temporal pole were highly correlated in leans but not in obese men. A trend for an association between MOR activation in the right temporal pole before weight loss and weight regain 1 year was found.
conclusionsAlthough these preliminary studies have a small sample size, these results suggest that obesity and diet-induced weight loss impact central MOR binding and endogenous opioid system function. MOR system activation in response to an acute meal may be related to the risk of weight regain.
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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.