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Rupp A, Young E, Chadwick AL. Low-dose naltrexone's utility for non-cancer centralized pain conditions: a scoping review. PAIN MEDICINE (MALDEN, MASS.) 2023; 24:1270-1281. [PMID: 37302106 PMCID: PMC10628981 DOI: 10.1093/pm/pnad074] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/24/2023] [Accepted: 06/02/2023] [Indexed: 06/13/2023]
Abstract
BACKGROUND At low doses, naltrexone (LDN) has been shown to modulate inflammation through the interruption of microglial cell activation within the central nervous system. One of the most likely contributors to centralized pain is changes in microglial cell processing. Therefore, it has been postulated that LDN can be used to manage patients with pain resulting from central sensitization due to this relationship. This scoping review aims to synthesize the relevant study data for LDN as a novel treatment strategy for various centralized pain conditions. METHODS A comprehensive literature search was conducted in PubMed, Embase, and Google Scholar, guided by the Scale for Assessment of Narrative Review Articles (SANRA) criteria. RESULTS Forty-seven studies related to centralized pain conditions were identified. Many of the studies were case reports/series and narrative reviews, but a few randomized control trials have been conducted. Overall, the body of evidence revealed improvement in patient-reported pain severity and in outcomes related to hyperalgesia, physical function, quality of life, and sleep. Variability in dosing paradigms and the time to patient response was present in the reviewed studies. CONCLUSIONS Evidence synthesized for this scoping review supports the ongoing use of LDN for the treatment of refractory pain in various centralized chronic pain conditions. Upon review of the currently available published studies, it is apparent that further high-quality, well-powered randomized control trials need to be conducted to establish efficacy, standardization for dosing, and response times. In summary, LDN continues to offer promising results in the management of pain and other distressing symptoms in patients with chronic centralized pain conditions.
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Affiliation(s)
- Adam Rupp
- Department of Physical Medicine and Rehabilitation, University of Kansas Medical Center, Kansas City, KS 66160, United States
| | - Erin Young
- Department of Anesthesiology, University of Kansas Medical Center, Kansas City, KS 66160, United States
| | - Andrea L Chadwick
- Department of Anesthesiology, University of Kansas Medical Center, Kansas City, KS 66160, United States
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2
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Bischoff SC, Ockenga J, Eshraghian A, Barazzoni R, Busetto L, Campmans-Kuijpers M, Cardinale V, Chermesh I, Kani HT, Khannoussi W, Lacaze L, Léon-Sanz M, Mendive JM, Müller MW, Tacke F, Thorell A, Vranesic Bender D, Weimann A, Cuerda C. Practical guideline on obesity care in patients with gastrointestinal and liver diseases - Joint ESPEN/UEG guideline. Clin Nutr 2023; 42:987-1024. [PMID: 37146466 DOI: 10.1016/j.clnu.2023.03.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 03/27/2023] [Indexed: 05/07/2023]
Abstract
BACKGROUND Patients with chronic gastrointestinal disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean gastrointestinal patients. The present guideline addresses this question according to current knowledge and evidence. OBJECTIVE The present practical guideline is intended for clinicians and practitioners in general medicine, gastroenterology, surgery and other obesity management, including dietitians and focuses on obesity care in patients with chronic gastrointestinal diseases. METHODS The present practical guideline is the shortened version of a previously published scientific guideline developed according to the standard operating procedure for ESPEN guidelines. The content has been re-structured and transformed into flow-charts that allow a quick navigation through the text. RESULTS In 100 recommendations (3× A, 33× B, 24 × 0, 40× GPP, all with a consensus grade of 90% or more) care of gastrointestinal patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially metabolic associated liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician. CONCLUSION The present practical guideline offers in a condensed way evidence-based advice how to care for patients with chronic gastrointestinal diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.
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Affiliation(s)
- Stephan C Bischoff
- Institute of Nutritional Medicine, University of Hohenheim, Stuttgart, Germany.
| | - Johann Ockenga
- Medizinische Klinik II, Klinikum Bremen-Mitte, Bremen FRG, Bremen, Germany.
| | - Ahad Eshraghian
- Department of Gastroenterology and Hepatology, Avicenna Hospital, Shiraz, Iran.
| | - Rocco Barazzoni
- Department of Medical, Technological and Translational Sciences, University of Trieste, Ospedale di Cattinara, Trieste, Italy.
| | - Luca Busetto
- Department of Medicine, University of Padova, Padova, Italy.
| | - Marjo Campmans-Kuijpers
- Department of Gastroenterology and Hepatology, University Medical Centre Groningen, Groningen, the Netherlands.
| | - Vincenzo Cardinale
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Rome, Italy.
| | - Irit Chermesh
- Department of Gastroenterology, Rambam Health Care Campus, Affiliated with Technion-Israel Institute of Technology, Haifa, Israel.
| | - Haluk Tarik Kani
- Department of Gastroenterology, Marmara University, School of Medicine, Istanbul, Turkey.
| | - Wafaa Khannoussi
- Hepato-Gastroenterology Department, Mohammed VI University Hospital, Oujda, Morocco; and Laboratoire de Recherche des Maladies Digestives (LARMAD), Mohammed the First University, Oujda, Morocco.
| | - Laurence Lacaze
- Department of General Surgery, Mantes-la-Jolie Hospital, Mantes-la-Jolie, France.
| | - Miguel Léon-Sanz
- Department of Endocrinology and Nutrition, University Hospital Doce de Octubre, Medical School, University Complutense, Madrid, Spain.
| | - Juan M Mendive
- La Mina Primary Care Academic Health Centre, Catalan Institute of Health (ICS), University of Barcelona, Barcelona, Spain.
| | - Michael W Müller
- Department of General and Visceral Surgery, Regionale Kliniken Holding, Kliniken Ludwigsburg-Bietigheim gGmbH, Krankenhaus Bietigheim, Bietigheim-Bissingen, Germany.
| | - Frank Tacke
- Department of Hepatology & Gastroenterology, Charité Universitätsmedizin Berlin, Campus Virchow-Klinikum and Campus Charité Mitte, Berlin, Germany.
| | - Anders Thorell
- Department of Clinical Science, Danderyds Hospital, Karolinska Institutet & Department of Surgery, Ersta Hospital, Stockholm, Sweden.
| | - Darija Vranesic Bender
- Unit of Clinical Nutrition, Department of Internal Medicine, University Hospital Centre Zagreb, Zagreb, Croatia.
| | - Arved Weimann
- Department of General, Visceral and Oncological Surgery, St. George Hospital, Leipzig, Germany.
| | - Cristina Cuerda
- Departamento de Medicina, Universidad Complutense de Madrid, Nutrition Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain.
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3
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Kim JH, Oh CM, Yoo JH. Obesity and novel management of inflammatory bowel disease. World J Gastroenterol 2023; 29:1779-1794. [PMID: 37032724 PMCID: PMC10080699 DOI: 10.3748/wjg.v29.i12.1779] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 01/13/2023] [Accepted: 03/14/2023] [Indexed: 03/28/2023] Open
Abstract
Obesity is prevalent within the inflammatory bowel disease (IBD) population, particularly in newly developed countries. Several epidemiological studies have suggested that 15%-40% of IBD patients are obese, and there is a potential role of obesity in the pathogenesis of IBD. The dysfunction of mesenteric fat worsens the inflammatory course of Crohn’s disease and may induce formation of strictures or fistulas. Furthermore, obesity may affect the disease course or treatment response of IBD. Given the increasing data supporting the pathophysiologic and epidemiologic relationship between obesity and IBD, obesity control is being suggested as a novel management for IBD. Therefore, this review aimed to describe the influence of obesity on the outcomes of IBD treatment and to present the current status of pharmacologic or surgical anti-obesity treatments in IBD patients.
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Affiliation(s)
- Jee Hyun Kim
- Department of Gastroenterology, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam 13496, South Korea
| | - Chang-Myung Oh
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 62465, South Korea
| | - Jun Hwan Yoo
- Department of Gastroenterology, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam 13496, South Korea
- Institute of Basic Medical Sciences, CHA University School of Medicine, Seongnam 13496, South Korea
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O'Kelly B, Vidal L, McHugh T, Woo J, Avramovic G, Lambert JS. Safety and efficacy of low dose naltrexone in a long covid cohort; an interventional pre-post study. Brain Behav Immun Health 2022; 24:100485. [PMID: 35814187 PMCID: PMC9250701 DOI: 10.1016/j.bbih.2022.100485] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 06/30/2022] [Accepted: 07/01/2022] [Indexed: 11/03/2022] Open
Abstract
Background Methods Findings Conclusions Low dose naltrexone (LDN) is safe to use in patients with long covid (LC). In patients with LC for a median 11 months, LDN reduced symptoms at 2 months. In this cohort, LDN also improved well-being in 6 of 7 parameters at 2 months.
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5
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Bischoff SC, Barazzoni R, Busetto L, Campmans-Kuijpers M, Cardinale V, Chermesh I, Eshraghian A, Kani HT, Khannoussi W, Lacaze L, Léon-Sanz M, Mendive JM, Müller MW, Ockenga J, Tacke F, Thorell A, Vranesic Bender D, Weimann A, Cuerda C. European guideline on obesity care in patients with gastrointestinal and liver diseases - Joint ESPEN/UEG guideline. Clin Nutr 2022; 41:2364-2405. [PMID: 35970666 DOI: 10.1016/j.clnu.2022.07.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 07/03/2022] [Indexed: 12/12/2022]
Abstract
BACKGROUND Patients with chronic gastrointestinal (GI) disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean GI patients. The present guideline addresses this question according to current knowledge and evidence. OBJECTIVE The objective of the guideline is to give advice to all professionals working in the field of gastroenterology care including physicians, surgeons, dietitians and others how to handle patients with GI disease and obesity. METHODS The present guideline was developed according to the standard operating procedure for ESPEN guidelines, following the Scottish Intercollegiate Guidelines Network (SIGN) grading system (A, B, 0, and good practice point (GPP)). The procedure included an online voting (Delphi) and a final consensus conference. RESULTS In 100 recommendations (3x A, 33x B, 24x 0, 40x GPP, all with a consensus grade of 90% or more) care of GI patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially fatty liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician. CONCLUSION The present guideline offers for the first time evidence-based advice how to care for patients with chronic GI diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.
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Affiliation(s)
- Stephan C Bischoff
- Institute of Nutritional Medicine, University of Hohenheim, Stuttgart, Germany.
| | - Rocco Barazzoni
- Department of Medical, Technological and Translational Sciences, University of Trieste, Ospedale di Cattinara, Trieste, Italy.
| | - Luca Busetto
- Department of Medicine, University of Padova, Padova, Italy.
| | - Marjo Campmans-Kuijpers
- Department of Gastroenterology and Hepatology, University Medical Centre Groningen, Groningen, the Netherlands.
| | - Vincenzo Cardinale
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Rome, Italy.
| | - Irit Chermesh
- Department of Gastroenterology, Rambam Health Care Campus, Affiliated with Technion-Israel Institute of Technology, Haifa, Israel.
| | - Ahad Eshraghian
- Department of Gastroenterology and Hepatology, Avicenna Hospital, Shiraz, Iran.
| | - Haluk Tarik Kani
- Department of Gastroenterology, Marmara University, School of Medicine, Istanbul, Turkey.
| | - Wafaa Khannoussi
- Hepato-Gastroenterology Department, Mohammed VI University Hospital, Oujda, Morocco; Laboratoire de Recherche des Maladies Digestives (LARMAD), Mohammed the First University, Oujda, Morocco.
| | - Laurence Lacaze
- Department of General Surgery, Mantes-la-Jolie Hospital, Mantes-la-Jolie, France; Department of Clinical Nutrition, Paul-Brousse-Hospital, Villejuif, France.
| | - Miguel Léon-Sanz
- Department of Endocrinology and Nutrition, University Hospital Doce de Octubre, Medical School, University Complutense, Madrid, Spain.
| | - Juan M Mendive
- La Mina Primary Care Academic Health Centre, Catalan Institute of Health (ICS), University of Barcelona, Barcelona, Spain.
| | - Michael W Müller
- Department of General and Visceral Surgery, Regionale Kliniken Holding, Kliniken Ludwigsburg-Bietigheim GGmbH, Krankenhaus Bietigheim, Bietigheim-Bissingen, Germany.
| | - Johann Ockenga
- Medizinische Klinik II, Klinikum Bremen-Mitte, Bremen FRG, Bremen, Germany.
| | - Frank Tacke
- Department of Hepatology & Gastroenterology, Charité Universitätsmedizin Berlin, Campus Virchow-Klinikum and Campus Charité Mitte, Berlin, Germany.
| | - Anders Thorell
- Department of Clinical Science, Danderyds Hospital, Karolinska Institutet & Department of Surgery, Ersta Hospital, Stockholm, Sweden.
| | - Darija Vranesic Bender
- Unit of Clinical Nutrition, Department of Internal Medicine, University Hospital Centre Zagreb, Zagreb, Croatia.
| | - Arved Weimann
- Department of General, Visceral and Oncological Surgery, St. George Hospital, Leipzig, Germany.
| | - Cristina Cuerda
- Departamento de Medicina, Universidad Complutense de Madrid, Nutrition Unit, Hospital General Universitario Gregorio Marañón, Madrid, Spain.
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Paulides E, Lie MRKL, van der Woude CJ. Low-dose naltrexone for the induction of remission in patients with mild to moderate Crohn's disease: protocol for the randomised, double-blinded, placebo-controlled, multicentre LDN Crohn study. BMJ Open 2022; 12:e058358. [PMID: 35396307 PMCID: PMC8996009 DOI: 10.1136/bmjopen-2021-058358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
INTRODUCTION Crohn's disease (CD) is an inflammatory bowel disease (IBD). Several drugs exist to induce and maintain remission, but a significant part of the patients is refractory to current IBD drugs or experiences side effects. Whether low-dose naltrexone (LDN) is a safe and easily accessible alternative treatment option for these patients needs to be investigated. The aim of this study is to assess the efficacy of LDN for the induction of remission in patients with mild to moderate CD. METHODS AND ANALYSIS The LDN Crohn study is a randomised, double-blinded, placebo-controlled multicentre trial. Patients with CD are randomised 1:1 to receive treatment with either LDN 4.5 mg once daily or placebo for 12 weeks. The primary objective is endoscopic remission at week 12, defined as Simple Endoscopic Score-CD≤2 and ulcerated surface subscore ≤1 in all five segments. Secondary aims include clinical and endoscopic response, changes in laboratory measures of inflammation, adverse events and patient-reported outcomes. To have 85% power to detect a true difference in the primary outcome measure between placebo and LDN, 61 patients will be needed in both groups. ETHICS AND DISSEMINATION The study is approved by the Medical Ethics Committee of the Erasmus MC, Rotterdam, the Netherlands (registration number NL69149.078.19, MEC-2019-0602). Results will be published in peer-reviewed journals and presented at international conferences. TRIAL REGISTRATION NUMBERS EudraCT2019-000852-32; NL9259.
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Affiliation(s)
- Emma Paulides
- Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Mitchell R K L Lie
- Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, Netherlands
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Kuźnicki P, Neubauer K. Emerging Comorbidities in Inflammatory Bowel Disease: Eating Disorders, Alcohol and Narcotics Misuse. J Clin Med 2021; 10:4623. [PMID: 34640641 PMCID: PMC8509435 DOI: 10.3390/jcm10194623] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/26/2021] [Accepted: 10/04/2021] [Indexed: 12/16/2022] Open
Abstract
Inflammatory bowel disease (IBD) is a chronic and potentially devastating condition of the digestive tract which is exemplified by increasing prevalence worldwide, byzantine pathogenesis with a poorly defined role of the environmental factors, and complex clinical demonstration. As a systemic disease, IBD may progress with a wide spectrum of extraintestinal manifestations (EMs) and comorbidities affecting different organs and systems, from anaemia, undernutrition, and cancer to those which are often neglected like anxiety and depression. Evolving IBD epidemiology and changing environment are reflected by an expanding list of IBD-related comorbidities. In contrast to the well-established role of smoking the connection between alcohol and IBD is still debatable on many levels, from pathogenesis to complications. Furthermore, little is known about narcotics use in IBD patients, even if there are obvious factors that may predispose them to narcotics as well as alcohol misuse. Last but not least, the question arises what is the prevalence of eating disorders in IBD. In our paper, we aimed to discuss the current knowledge on alcohol and drugs misuse and eating disorders as emerging extraintestinal comorbidities in IBD.
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Affiliation(s)
- Paweł Kuźnicki
- Department of Gastroenterology and Hepatology, Wroclaw Medical University, Borowska 213, 50-556 Wroclaw, Poland;
| | - Katarzyna Neubauer
- Department of Gastroenterology and Hepatology, Division of Dietetics, Wroclaw Medical University, Borowska 213, 50-556 Wroclaw, Poland
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8
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Reported Benefits of Low-Dose Naltrexone Appear to Be Independent of the Endogenous Opioid System Involving Proopiomelanocortin Neurons and β-Endorphin. eNeuro 2021; 8:ENEURO.0087-21.2021. [PMID: 34031099 PMCID: PMC8211470 DOI: 10.1523/eneuro.0087-21.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 05/08/2021] [Accepted: 05/14/2021] [Indexed: 11/25/2022] Open
Abstract
Naltrexone is an opioid receptor antagonist approved for the treatment of alcohol and opioid use disorders at doses of 50–150 mg/d. Naltrexone has also been prescribed at much lower doses (3–6 mg/d) for the off-label treatment of inflammation and pain. Currently, a compelling mechanistic explanation for the reported efficacy of low-dose naltrexone (LDN) is lacking and none of the proposed mechanisms can explain patient reports of improved mood and sense of well-being. Here, we examined the possibility that LDN might alter the activity of the endogenous opioid system involving proopiomelanocortin (POMC) neurons in the arcuate nucleus of the hypothalamus (ARH) in male and female mice. Known actions of POMC neurons could account for changes in pain perception and mood. However, using electrophysiologic, imaging and peptide measurement approaches, we found no evidence for such a mechanism. LDN did not change the sensitivity of opioid receptors regulating POMC neurons, the production of the β-endorphin precursor Pomc mRNA, nor the release of β-endorphin into plasma. Spontaneous postsynaptic currents (sPSCs) onto POMC neurons were slightly decreased after LDN treatment and GCaMP fluorescent signal, a proxy for intracellular calcium levels, was slightly increased. However, LDN treatment did not appear to change POMC neuron firing rate, resting membrane potential, nor action potential threshold. Therefore, LDN appears to have only slight effects on POMC neurons that do not translate to changes in intrinsic excitability or baseline electrical activity and mechanisms beyond POMC neurons and altered opioid receptor sensitivity should continue to be explored.
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Abstract
In traditional medicine, Cannabis sativa has been prescribed for a variety of diseases. Today, the plant is largely known for its recreational purpose, but it may find a way back to what it was originally known for: a herbal remedy. Most of the plant's ingredients, such as Δ-tetrahydrocannabinol, cannabidiol, cannabigerol, and others, have demonstrated beneficial effects in preclinical models of intestinal inflammation. Endogenous cannabinoids (endocannabinoids) have shown a regulatory role in inflammation and mucosal permeability of the gastrointestinal tract where they likely interact with the gut microbiome. Anecdotal reports suggest that in humans, Cannabis exerts antinociceptive, anti-inflammatory, and antidiarrheal properties. Despite these reports, strong evidence on beneficial effects of Cannabis in human gastrointestinal diseases is lacking. Clinical trials with Cannabis in patients suffering from inflammatory bowel disease (IBD) have shown improvement in quality of life but failed to provide evidence for a reduction of inflammation markers. Within the endogenous opioid system, mu opioid receptors may be involved in anti-inflammation of the gut. Opioids are frequently used to treat abdominal pain in IBD; however, heavy opioid use in IBD is associated with opioid dependency and higher mortality. This review highlights latest advances in the potential treatment of IBD using Cannabis/cannabinoids or opioids.
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Abstract
This paper is the forty-first consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2018 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (2), the roles of these opioid peptides and receptors in pain and analgesia in animals (3) and humans (4), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (5), opioid peptide and receptor involvement in tolerance and dependence (6), stress and social status (7), learning and memory (8), eating and drinking (9), drug abuse and alcohol (10), sexual activity and hormones, pregnancy, development and endocrinology (11), mental illness and mood (12), seizures and neurologic disorders (13), electrical-related activity and neurophysiology (14), general activity and locomotion (15), gastrointestinal, renal and hepatic functions (16), cardiovascular responses (17), respiration and thermoregulation (18), and immunological responses (19).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY, 11367, United States.
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11
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Raknes G, Småbrekke L. No change in the consumption of thyroid hormones after starting low dose naltrexone (LDN): a quasi-experimental before-after study. BMC Endocr Disord 2020; 20:151. [PMID: 33004044 PMCID: PMC7528597 DOI: 10.1186/s12902-020-00630-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 09/24/2020] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Low dose naltrexone (LDN) is reported to have beneficial effects in several autoimmune diseases. The purpose of this study was to examine whether starting LDN was followed by changes in the dispensing of thyroid hormones to patients with hypothyroidism. METHODS We performed a quasi-experimental before-after study based on the Norwegian Prescription Database. Study participants were identified by using reimbursement codes for hypothyroidism. Cumulative dispensed Defined Daily Doses and the number of users of triiodothyronine (T3) and levothyroxine (LT4) 1 year before and after the first LDN prescription was compared in three groups based on LDN exposure. RESULTS We identified 898 patients that met the inclusion criteria. There was no association between starting LDN and the subsequent dispensing of thyroid hormones. If anything, there was a tendency towards increasing LT4 consumption with increasing LDN exposure. CONCLUSION The results of this study do not support claims of efficacy of LDN in hypothyroidism.
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Affiliation(s)
- Guttorm Raknes
- Regional Medicines Information and Pharmacovigilance Centre (RELIS), University Hospital of North Norway, Tromsø, Norway
- Raknes Research, Ulset, Norway
| | - Lars Småbrekke
- Department of Pharmacy, Faculty of Health Sciences, UiT - The arctic university of Norway, Tromsø, Norway.
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12
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Bobo TR, Fitzpatrick LR, Whitcomb TL, Cooper TK, Raiciulescu S, Smith JP. Role of the δ-Opioid Receptor in 2 Murine Models of Colitis. Comp Med 2020; 70:25-34. [PMID: 31969211 DOI: 10.30802/aalas-cm-19-000024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Crohn disease and ulcerative colitis, collectively referred to as inflammatory bowel disease (IBD), are chronic inflammatory disorders of the gastrointestinal tract. Currently, the etiology of IBD is unknown, and immunosuppressive therapies have become the standard of care to reduce the inflammation; however, these agents only induce remission 50% of the time in patients and can have serious side effects. Recently, endogenous opioids and opioid receptors have been shown to play a role in the mediation of inflammation. In addition, opioid receptor blockade with a nonselective antagonist, naltrexone, has been shown to reduce colitis in both murine models and human subjects. The goal of the current study was to determine if the antiinflammatory effects of naltrexone are mediated through the delta (δ) opioid receptor. Male C57BL/6NCrl (6 to 8 wk.; n = 110) and female BALB/cAnNCrl (6-8 wk.; n = 91) mice were studied using 2 animal models of chemically induced colitis: dextran sodium sulfate (DSS) and 2, 4, 6-trinitrobenzenesulfonic acid (TNBS). The selective δ-receptor antagonists naltrindole and 7-benzylidenenaltrexone were administered to examine the role of the δ-opioid receptor in colonic inflammation. The quantitative measurement of colitis activity, colon weight and length, Hct, WBC count, and gross and microscopic aberrations were analyzed. Administration of naltrexone in the DSS colitis model significantly improved overall disease activity indices on day 5 of therapy. The use of δ-antagonists and naltrexone had limited to no effect on TNBS colitis. Similar findings were obtained by using the DSS colitis model. Based on the current findings, the authors conclude that naltrexone therapy has limited effect on the improvement of colitis in 2 murine models; however, the δ-opioid receptor was not responsible for mediating the effects.
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Affiliation(s)
- Tia R Bobo
- Department of Comparative Medicine, Penn State College of Medicine, Hershey, Pennsylvania; Office of Animal Research, The George Washington University, Washington DC;,
| | - Leo R Fitzpatrick
- Department of Pharmacology, Penn State College of Medicine, Hershey, Pennsylvania; Department of Pharmaceutical & Biomedical Sciences, California Northstate University, Elk Grove, California
| | - Tiffany L Whitcomb
- Department of Comparative Medicine, Penn State College of Medicine, Hershey, Pennsylvania
| | - Timothy K Cooper
- Department of Comparative Medicine, Penn State College of Medicine, Hershey, Pennsylvania; Department of Pathology, Penn State College of Medicine, Hershey, Pennsylvania; Charles River Laboratories, Contractor Supporting National Institute of Allergy and Infectious Disease, Frederick, Maryland
| | - Sorana Raiciulescu
- Department of Preventive Medicine and Biostatistics, Uniformed Services University, Bethesda, Maryland
| | - Jill P Smith
- Department of Medicine, Penn State College of Medicine, Hershey, Pennsylvania; Department of Medicine, Georgetown University, Washington, DC
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Bolton MJ, Chapman BP, Van Marwijk H. Low-dose naltrexone as a treatment for chronic fatigue syndrome. BMJ Case Rep 2020; 13:e232502. [PMID: 31911410 PMCID: PMC6954765 DOI: 10.1136/bcr-2019-232502] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2019] [Indexed: 12/29/2022] Open
Abstract
Naltrexone is used as an off-label treatment in low doses for several chronic immune-modulated disorders in many countries. Although only small-scale clinical trials have been performed, these suggest efficacy in several diseases including Crohn's disease, fibromyalgia and Gulf War Illness. Despite numerous internet reports of response to low-dose naltrexone (LDN), no clinical trials exist in people with chronic fatigue syndrome. This condition is characterised by chronic profound fatigue, postexertional malaise, pain and autonomic and neurocognitive disturbances. This series of three case reports compiled by people with long-term ill-health due to chronic fatigue syndrome shows the range of responses they observed when taking LDN, from life changing to a reduction in some symptoms only. Treatment doses ranged from 4 to 12 mg. Clinical trials may be warranted to explore the potential use of naltrexone in people with these debilitating illnesses which currently have no licensed treatments available.
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Affiliation(s)
| | | | - Harm Van Marwijk
- Department of Primary Care and Public Health, Brighton and Sussex Medical School, Brighton, UK
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Xu N, Wang Y, Zhao S, Jiao T, Xue H, Shan F, Zhang N. Naltrexone (NTX) relieves inflammation in the collagen-induced- arthritis (CIA) rat models through regulating TLR4/NFκB signaling pathway. Int Immunopharmacol 2019; 79:106056. [PMID: 31865244 DOI: 10.1016/j.intimp.2019.106056] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 11/13/2019] [Accepted: 11/13/2019] [Indexed: 10/25/2022]
Abstract
OBJECTIVE Our aim was to study the efficacy and mechanism by which NTX alleviate arthritis in CIA rat models in vivo. METHODS Female Wistar rats were randomly divided into 6 groups, their weights were observed and the severity of arthritis and pathological changes were evaluated by HE staining. T lymphocyte subsets were detected by flow cytometry. The expression of cytokines was detected in peripheral serum by ELISA. Real time PCR, immunohistochemical staining and western blot analysis were utilized to detect the mRNA and protein expression of opioid receptors, TLR4, RANKL and /NF-κB in synovial tissue and the spleen. RESULTS The weight of the rats in the 10 mg/kg NTX group decreased the least, and had the least severe arthritis. CD4+ T cells, Th1 cells and Treg cells increased, and CD8+T cells, Th1 cells and Th17 cells decreased in the splenic lymphocytes. The expression of proinflammatory cytokines decreased, and the expression of anti-inflammatory cytokines increased. MOR and DOR were strongly expressed in the spleen, whereas KOR and DOR were strongly expressed in synovial tissue. The expression of TLR4, NF-κB and RANKL was reduced in the spleen and synovium in the NTX group. CONCLUSIONS NTX relieved the severity of arthritis in the CIA rat models at a concentration of 10 mg/kg by regulating T lymphocyte subsets and the expression of cytokines. NTX affected opioid receptors to inhibit the TLR4/NF-κB signaling pathway, regulating the systemic immune response and decreasing osteoclast differentiation, thereby alleviating inflammation and the erosion of articular cartilage along with bone tissue.
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Affiliation(s)
- Neili Xu
- Department of Rheumatology, Shengjing Hospital of China Medical University, China
| | - Yuejiao Wang
- Department of Rheumatology, Shengjing Hospital of China Medical University, China
| | - Shuai Zhao
- Department of Rheumatology, Shengjing Hospital of China Medical University, China
| | - Ting Jiao
- Department of Rheumatology, Shengjing Hospital of China Medical University, China
| | - Hongxia Xue
- Department of Rheumatology, Shengjing Hospital of China Medical University, China
| | - Fengping Shan
- Department of Immunology, College of Basic Medical Science, China Medical University, China
| | - Ning Zhang
- Department of Rheumatology, Shengjing Hospital of China Medical University, China.
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Changes in the consumption of antiepileptics and psychotropic medicines after starting low dose naltrexone: A nation-wide register-based controlled before-after study. Sci Rep 2019; 9:15085. [PMID: 31636347 PMCID: PMC6803623 DOI: 10.1038/s41598-019-51569-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 10/03/2019] [Indexed: 01/03/2023] Open
Abstract
In this controlled before-after study based on data from the Norwegian Prescription Database, we examine whether starting off-label use of Low Dose Naltrexone (LDN) is followed by changes in the consumption of psychotropic medicines including antiepileptics. Patients that collected LDN for the first time in 2013 (N = 11247) were included and stratified into three groups based on LDN exposure. We compared differences in means of cumulative number of defined daily doses (DDD) as well as changes in the number of users one year before and one year after starting LDN. There was a dose-response association between increasing LDN exposure and reductions in the number of users of antiepileptics, antipsychotics and antidepressants. There were significant difference-in-differences in DDDs between the groups with the lowest and highest LDN exposure of antipsychotics (1.4 DDD, 95% CI 0.4 to 2.3, p = 0.007), and in number of users of antiepileptics (3.1% points, 95% CI 1.6% to 4.6%, p < 0.001), antipsychotics (2.1% points, 95% CI 1.2% to 3%, p < 0.001), and antidepressants (2.8% points, 95% CI 1.1% to 4.4%, p = 0.001). The findings show an association between the initiation of persistent LDN use and reduced consumption of several psychotropic medicines and antiepileptics. Beneficial effects of LDN in the treatment of psychiatric diseases cannot be ruled out.
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Komla E, Stevens DL, Zheng Y, Zhang Y, Dewey WL, Akbarali HI. Experimental Colitis Enhances the Rate of Antinociceptive Tolerance to Morphine via Peripheral Opioid Receptors. J Pharmacol Exp Ther 2019; 370:504-513. [PMID: 31248978 PMCID: PMC6806632 DOI: 10.1124/jpet.119.256941] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 06/24/2019] [Indexed: 01/21/2023] Open
Abstract
Opioids are highly effective analgesics, however, their therapeutic use is limited by adverse effects that include respiratory depression, dependence, and tolerance. Inflammation has been implicated as a significant driver for the development of tolerance to opioids. Recent studies show that chronic morphine in mice results in gut microbial dysbiosis and inflammation in the colon. In the present study, we examined whether colonic inflammation results in tolerance to the antinociceptive effects of morphine. Colonic inflammation was induced in mice by intrarectal administration of 2,4,6-trinitro-benzene sulfonic acid. The development of antinociceptive tolerance was determined by warm-water tail-immersion assay in mice implanted with 25-, 50-, or 75-mg morphine pellet. Colonic inflammation significantly enhanced the rate at which tolerance developed in each cohort of chronic morphine-treated mice. At the lowest dose of morphine pellet (25 mg), antinociceptive tolerance only developed in the presence of colonic inflammation, whereas in 50- and 75-mg pelleted mice, tolerance developed faster in the inflamed animals than in the noninflamed mice. The enhanced antinociceptive tolerance was attenuated with daily administration of peripheral opioid receptor antagonist, 6β-N-heterocyclic-substituted naltrexamine derivative [17-cyclopropylmethyl-3,14β-dihydroxy-4,5α-epoxy-6β-[(4'pyridyl)acetamido]morphinan (NAP)], irrespective of colonic inflammation. Collectively, these findings show that the rate of tolerance to morphine antinociception is exaggerated in the presence of colonic inflammation, and tolerance is prevented by a peripheral μ-opioid receptor antagonist. These studies suggest a peripheral component to the development of antinociceptive tolerance to opioids. Furthermore, peripherally selective opioid antagonists may be useful adjuncts in opioid-based pain management. SIGNIFICANCE STATEMENT: This study supports the notion that inflammation influences the development of antinociceptive tolerance to chronic morphine exposure. We found that, in the presence of colonic inflammation, the rate of development of tolerance to the antinociceptive effects of morphine increased. We also found that treatment with a peripheral opioid receptor antagonist prevented morphine antinociceptive tolerance. Increasing opioid intake during an inflammatory state would result in decreased analgesia and enhanced analgesic tolerance, which puts patients with inflammatory bowel diseases, inflammatory joint diseases, and sickle cell anemia at risk for heavy opioid use.
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Affiliation(s)
- Essie Komla
- Departments of Pharmacology and Toxicology (E.K., D.L.S., W.L.D., H.I.A.) and Medicinal Chemistry (Y.Zhe., Y.Zha.), Virginia Commonwealth University, Richmond, Virginia
| | - David L Stevens
- Departments of Pharmacology and Toxicology (E.K., D.L.S., W.L.D., H.I.A.) and Medicinal Chemistry (Y.Zhe., Y.Zha.), Virginia Commonwealth University, Richmond, Virginia
| | - Yi Zheng
- Departments of Pharmacology and Toxicology (E.K., D.L.S., W.L.D., H.I.A.) and Medicinal Chemistry (Y.Zhe., Y.Zha.), Virginia Commonwealth University, Richmond, Virginia
| | - Yan Zhang
- Departments of Pharmacology and Toxicology (E.K., D.L.S., W.L.D., H.I.A.) and Medicinal Chemistry (Y.Zhe., Y.Zha.), Virginia Commonwealth University, Richmond, Virginia
| | - William L Dewey
- Departments of Pharmacology and Toxicology (E.K., D.L.S., W.L.D., H.I.A.) and Medicinal Chemistry (Y.Zhe., Y.Zha.), Virginia Commonwealth University, Richmond, Virginia
| | - Hamid I Akbarali
- Departments of Pharmacology and Toxicology (E.K., D.L.S., W.L.D., H.I.A.) and Medicinal Chemistry (Y.Zhe., Y.Zha.), Virginia Commonwealth University, Richmond, Virginia
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Low dose naltrexone: Effects on medication in rheumatoid and seropositive arthritis. A nationwide register-based controlled quasi-experimental before-after study. PLoS One 2019; 14:e0212460. [PMID: 30763385 PMCID: PMC6375629 DOI: 10.1371/journal.pone.0212460] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 02/01/2019] [Indexed: 11/19/2022] Open
Abstract
In recent years, low dose naltrexone (LDN) has been used as an off-label therapy for several chronic diseases. Results from small laboratory and clinical studies indicate some beneficial effects of LDN in autoimmune diseases, but clinical research on LDN in rheumatic disease is limited. Using a pharmacoepidemiological approach, we wanted to test the hypothesis that starting LDN leads to reduced dispensing of medicines used in the treatment of rheumatic disease. We performed a controlled before-after study based on the Norwegian Prescription Database (NorPD) to compare prescriptions to patients one year before and one year after starting LDN in 2013. The identified patients (n = 360) were stratified into three groups based on LDN exposure. Outcomes were differences in dispensing of medicines used in rheumatic disease. In persistent LDN users, there was a 13% relative reduction in cumulative defined daily doses (DDD) of all medicines examined corresponding to -73.3 DDD per patient (95% CI -120,2 to -26.4, p = 0.003), and 23% reduction of analgesics (-21.6 DDD (95% CI -35.5 to -7.6, p<0.009)). There was no significant DDD change in patients with lower LDN exposure. Persistent LDN users had significantly reduced DDDs of NSAID and opioids, and a lower proportion of users of DMARDs (-6.7 percentage points, 95% CI -12.3 to-1.0, p = 0.028), TNF-α antagonists and opioids. There was a decrease in the number of NSAID users among patients with the least LDN exposure. Important limitations are that prescription data are proxies for clinical effects and that a control group unexposed to LDN is lacking. The results support the hypothesis that persistent use of LDN reduces the need for medication used in the treatment of rheumatic and seropositive arthritis. Randomised clinical trials on LDN in rheumatic disease are warranted.
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Bolton M, Hodkinson A, Boda S, Mould A, Panagioti M, Rhodes S, Riste L, van Marwijk H. Serious adverse events reported in placebo randomised controlled trials of oral naltrexone: a systematic review and meta-analysis. BMC Med 2019; 17:10. [PMID: 30642329 PMCID: PMC6332608 DOI: 10.1186/s12916-018-1242-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 12/17/2018] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Naltrexone is an opioid antagonist used in many different conditions, both licensed and unlicensed. It is used at widely varying doses from 3 to 250 mg. The aim of this review was to extensively evaluate the safety of oral naltrexone by examining the risk of serious adverse events and adverse events in randomised controlled trials of naltrexone compared to placebo. METHODS A systematic search of the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, other databases and clinical trials registries was undertaken up to May 2018. Parallel placebo-controlled randomised controlled trials longer than 4 weeks published after 1 January 2001 of oral naltrexone at any dose were selected. Any condition or age group was included, excluding only studies in opioid or ex-opioid users owing to possible opioid/opioid antagonist interactions. The systematic review used the guidance of the Cochrane Handbook and Preferred Reporting Items for Systematic Reviews and Meta-analyses harms checklist throughout. Numerical data were independently extracted by two people and cross-checked. Risk of bias was assessed with the Cochrane risk-of-bias tool. Meta-analyses were performed in R using random effects models throughout. RESULTS Eighty-nine randomised controlled trials with 11,194 participants were found, studying alcohol use disorders (n = 38), various psychiatric disorders (n = 13), impulse control disorders (n = 9), other addictions including smoking (n = 18), obesity or eating disorders (n = 6), Crohn's disease (n = 2), fibromyalgia (n = 1) and cancers (n = 2). Twenty-six studies (4,960 participants) recorded serious adverse events occurring by arm of study. There was no evidence of increased risk of serious adverse events for naltrexone compared to placebo (risk ratio 0.84, 95% confidence interval 0.66-1.06). Sensitivity analyses pooling risk differences supported this conclusion (risk difference -0.01, 95% confidence interval -0.02-0.00) and subgroup analyses showed that results were consistent across different doses and disease groups. Secondary analysis revealed only six marginally significant adverse events for naltrexone compared to placebo, which were of mild severity. CONCLUSIONS Naltrexone does not appear to increase the risk of serious adverse events over placebo. These findings confirm the safety of oral naltrexone when used in licensed indications and encourage investments to undertake efficacy studies in unlicensed indications. TRIAL REGISTRATION PROSPERO 2017 CRD42017054421 .
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Affiliation(s)
- Monica Bolton
- School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PL, UK
| | - Alex Hodkinson
- Centre for Primary Care, Division of Population Health, Health Services Research & Primary Care, Williamson Building, Oxford Road, Manchester, M13 9PL, UK.
| | - Shivani Boda
- School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PL, UK
| | - Alan Mould
- Centre for Primary Care, Division of Population Health, Health Services Research & Primary Care, Williamson Building, Oxford Road, Manchester, M13 9PL, UK
| | - Maria Panagioti
- NIHR School for Primary Care Research, NIHR Greater Manchester Primary Care Patient Safety Translational Research Centre, Manchester Academic Health Science Centre, University of Manchester, Brighton, M13 9PL, UK
| | - Sarah Rhodes
- Centre for Biostatistics, Division of Population Health, Health Services Research and Primary Care, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PL, UK
| | - Lisa Riste
- Division of Population Health, Health Services Research and Primary Care, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PL, UK
| | - Harm van Marwijk
- Division of Population Health, Health Services Research and Primary Care, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PL, UK
- Brighton and Sussex Medical School, Watson Building, University of Brighton, Brighton, BN1 9PH, UK
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Zagon IS, McLaughlin PJ. Intermittent blockade of OGFr and treatment of autoimmune disorders. Exp Biol Med (Maywood) 2018; 243:1323-1330. [PMID: 30541348 PMCID: PMC6348594 DOI: 10.1177/1535370218817746] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
IMPACT STATEMENT This mini-review presents information on the intermittent blockade of the opioid growth factor (OGF)-OGF receptor (OGFr) axis by low-dose naltrexone (LDN), and the role of enkephalin (i.e. OGF) in autoimmune disorders, specifically multiple sclerosis, Crohn's, and fibromyalgia. Clinical reports on subjects taking LDN have documented reduced fatigue, few side-effects, and improved overall health. Preclinical studies on mice with experimental autoimmune encephalomyelitis (EAE), the animal model of multiple sclerosis, revealed that immunization for EAE reduces serum OGF. Intermittent OGFr blockade with LDN restores serum enkephalin levels that correlate with reduced behavioral and pathological signs of EAE; LDN also increases enkephalin levels in naïve mice. The interplay between LDN, and the onset and treatment of autoimmune diseases, chronic pain, and other addictive behaviors requires further investigation, but highlights a central role for enkephalins and intermittent blockade of the OGF-OGFr pathway in pathogenesis and treatment of these disorders.
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Affiliation(s)
- Ian S Zagon
- Department of Neural & Behavioral Sciences, Penn
State University College of Medicine, Hershey, PA 17033, USA
| | - Patricia J McLaughlin
- Department of Neural & Behavioral Sciences, Penn
State University College of Medicine, Hershey, PA 17033, USA
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Toljan K, Vrooman B. Low-Dose Naltrexone (LDN)-Review of Therapeutic Utilization. Med Sci (Basel) 2018; 6:medsci6040082. [PMID: 30248938 PMCID: PMC6313374 DOI: 10.3390/medsci6040082] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 09/16/2018] [Accepted: 09/18/2018] [Indexed: 02/07/2023] Open
Abstract
Naltrexone and naloxone are classical opioid antagonists. In substantially lower than standard doses, they exert different pharmacodynamics. Low-dose naltrexone (LDN), considered in a daily dose of 1 to 5 mg, has been shown to reduce glial inflammatory response by modulating Toll-like receptor 4 signaling in addition to systemically upregulating endogenous opioid signaling by transient opioid-receptor blockade. Clinical reports of LDN have demonstrated possible benefits in diseases such as fibromyalgia, Crohn’s disease, multiple sclerosis, complex-regional pain syndrome, Hailey-Hailey disease, and cancer. In a dosing range at less than 1 μg per day, oral naltrexone or intravenous naloxone potentiate opioid analgesia by acting on filamin A, a scaffolding protein involved in μ-opioid receptor signaling. This dose is termed ultra low-dose naltrexone/naloxone (ULDN). It has been of use in postoperative control of analgesia by reducing the need for the total amount of opioids following surgery, as well as ameliorating certain side-effects of opioid-related treatment. A dosing range between 1 μg and 1 mg comprises very low-dose naltrexone (VLDN), which has primarily been used as an experimental adjunct treatment for boosting tolerability of opioid-weaning methadone taper. In general, all of the low-dose features regarding naltrexone and naloxone have been only recently and still scarcely scientifically evaluated. This review aims to present an overview of the current knowledge on these topics and summarize the key findings published in peer-review sources. The existing potential of LDN, VLDN, and ULDN for various areas of biomedicine has still not been thoroughly and comprehensively addressed.
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Affiliation(s)
- Karlo Toljan
- Department of Pathophysiology, University of Zagreb School of Medicine, Kispaticeva 12, 10 000 Zagreb, Croatia.
| | - Bruce Vrooman
- Section of Pain Medicine, Department of Anesthesiology, Dartmouth-Hitchcock Medical Center, 1 Medical Center Dr, Lebanon, NH 03756, USA.
- Department of Anesthesiology, Geisel School of Medicine at Dartmouth, Hanover, NH 03756, USA.
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