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Crews FT, Coleman LG, Macht VA, Vetreno RP. Alcohol, HMGB1, and Innate Immune Signaling in the Brain. Alcohol Res 2024; 44:04. [PMID: 39135668 PMCID: PMC11318841 DOI: 10.35946/arcr.v44.1.04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2024] Open
Abstract
PURPOSE Binge drinking (i.e., consuming enough alcohol to achieve a blood ethanol concentration of 80 mg/dL, approximately 4-5 drinks within 2 hours), particularly in early adolescence, can promote progressive increases in alcohol drinking and alcohol-related problems that develop into compulsive use in the chronic relapsing disease, alcohol use disorder (AUD). Over the past decade, neuroimmune signaling has been discovered to contribute to alcohol-induced changes in drinking, mood, and neurodegeneration. This review presents a mechanistic hypothesis supporting high mobility group box protein 1 (HMGB1) and Toll-like receptor (TLR) signaling as key elements of alcohol-induced neuroimmune signaling across glia and neurons, which shifts gene transcription and synapses, altering neuronal networks that contribute to the development of AUD. This hypothesis may help guide further research on prevention and treatment. SEARCH METHODS The authors used the search terms "HMGB1 protein," "alcohol," and "brain" across PubMed, Scopus, and Embase to find articles published between 1991 and 2023. SEARCH RESULTS The database search found 54 references in PubMed, 47 in Scopus, and 105 in Embase. A total of about 100 articles were included. DISCUSSION AND CONCLUSIONS In the brain, immune signaling molecules play a role in normal development that differs from their functions in inflammation and the immune response, although cellular receptors and signaling are shared. In adults, pro-inflammatory signals have emerged as contributing to brain adaptation in stress, depression, AUD, and neurodegenerative diseases. HMGB1, a cytokine-like signaling protein released from activated cells, including neurons, is hypothesized to activate pro-inflammatory signals through TLRs that contribute to adaptations to binge and chronic heavy drinking. HMGB1 alone and in heteromers with other molecules activates TLRs and other immune receptors that spread signaling across neurons and glia. Both blood and brain levels of HMGB1 increase with ethanol exposure. In rats, an adolescent intermittent ethanol (AIE) binge drinking model persistently increases brain HMGB1 and its receptors; alters microglia, forebrain cholinergic neurons, and neuronal networks; and increases alcohol drinking and anxiety while disrupting cognition. Studies of human postmortem AUD brain have found elevated levels of HMGB1 and TLRs. These signals reduce cholinergic neurons, whereas microglia, the brain's immune cells, are activated by binge drinking. Microglia regulate synapses through complement proteins that can change networks affected by AIE that increase drinking, contributing to risks for AUD. Anti-inflammatory drugs, exercise, cholinesterase inhibitors, and histone deacetylase epigenetic inhibitors prevent and reverse the AIE-induced pathology. Further, HMGB1 antagonists and other anti-inflammatory treatments may provide new therapies for alcohol misuse and AUD. Collectively, these findings suggest that restoring the innate immune signaling balance is central to recovering from alcohol-related pathology.
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Affiliation(s)
- Fulton T. Crews
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, North Carolina
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
- Department of Psychiatry, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Leon G. Coleman
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, North Carolina
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Victoria A. Macht
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Ryan P. Vetreno
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, North Carolina
- Department of Psychiatry, University of North Carolina School of Medicine, Chapel Hill, North Carolina
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2
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Trang KB, Chesi A, Toikumo S, Pippin JA, Pahl MC, O’Brien JM, Amundadottir LT, Brown KM, Yang W, Welles J, Santoleri D, Titchenell PM, Seale P, Zemel BS, Wagley Y, Hankenson KD, Kaestner KH, Anderson SA, Kayser MS, Wells AD, Kranzler HR, Kember RL, Grant SF. Shared and unique 3D genomic features of substance use disorders across multiple cell types. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.07.18.24310649. [PMID: 39072016 PMCID: PMC11275669 DOI: 10.1101/2024.07.18.24310649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Recent genome-wide association studies (GWAS) have revealed shared genetic components among alcohol, opioid, tobacco and cannabis use disorders. However, the extent of the underlying shared causal variants and effector genes, along with their cellular context, remain unclear. We leveraged our existing 3D genomic datasets comprising high-resolution promoter-focused Capture-C/Hi-C, ATAC-seq and RNA-seq across >50 diverse human cell types to focus on genomic regions that coincide with GWAS loci. Using stratified LD regression, we determined the proportion of genomewide SNP heritability attributable to the features assayed across our cell types by integrating recent GWAS summary statistics for the relevant traits: alcohol use disorder (AUD), tobacco use disorder (TUD), opioid use disorder (OUD) and cannabis use disorder (CanUD). Statistically significant enrichments (P<0.05) were observed in 14 specific cell types, with heritability reaching 9.2-fold for iPSC-derived cortical neurons and neural progenitors, confirming that they are crucial cell types for further functional exploration. Additionally, several pancreatic cell types, notably pancreatic beta cells, showed enrichment for TUD, with heritability enrichments up to 4.8-fold, suggesting genomic overlap with metabolic processes. Further investigation revealed significant positive genetic correlations between T2D with both TUD and CanUD (FDR<0.05) and a significant negative genetic correlation with AUD. Interestingly, after partitioning the heritability for each cell type's cis-regulatory elements, the correlation between T2D and TUD for pancreatic beta cells was greater (r=0.2) than the global genetic correlation value. Our study provides new genomic insights into substance use disorders and implicates cell types where functional follow-up studies could reveal causal variant-gene mechanisms underpinning these disorders.
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Affiliation(s)
- Khanh B. Trang
- Center for Spatial and Functional Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Human Genetics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Alessandra Chesi
- Center for Spatial and Functional Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Sylvanus Toikumo
- Mental Illness Research, Education and Clinical Center, Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - James A. Pippin
- Center for Spatial and Functional Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Human Genetics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Matthew C. Pahl
- Center for Spatial and Functional Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Human Genetics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Joan M. O’Brien
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, PA, USA
- Penn Medicine Center for Ophthalmic Genetics in Complex Disease, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, PA, USA
| | - Laufey T. Amundadottir
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA
| | - Kevin M. Brown
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA
| | - Wenli Yang
- Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jaclyn Welles
- Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Dominic Santoleri
- Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Paul M. Titchenell
- Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Patrick Seale
- Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Babette S. Zemel
- Division of Gastroenterology, Hepatology, and Nutrition, Children’s Hospital of Philadelphia, PA, USA
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yadav Wagley
- Department of Orthopedic Surgery, University of Michigan Medical School Ann Arbor, MI, USA
| | - Kurt D. Hankenson
- Department of Orthopedic Surgery, University of Michigan Medical School Ann Arbor, MI, USA
| | - Klaus H. Kaestner
- Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Stewart A. Anderson
- Department of Child and Adolescent Psychiatry, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Matthew S. Kayser
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Chronobiology Sleep Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Andrew D. Wells
- Center for Spatial and Functional Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Institute for Immunology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Henry R. Kranzler
- Mental Illness Research, Education and Clinical Center, Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Rachel L. Kember
- Mental Illness Research, Education and Clinical Center, Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Struan F.A. Grant
- Center for Spatial and Functional Genomics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Division of Human Genetics, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
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Heilig M, Witkiewitz K, Ray LA, Leggio L. Novel medications for problematic alcohol use. J Clin Invest 2024; 134:e172889. [PMID: 38828724 PMCID: PMC11142745 DOI: 10.1172/jci172889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024] Open
Abstract
Alcohol-related harm, a major cause of disease burden globally, affects people along a spectrum of use. When a harmful pattern of drinking is present in the absence of significant behavioral pathology, low-intensity brief interventions that provide information about health consequences of continued use provide large health benefits. At the other end of the spectrum, profound behavioral pathology, including continued use despite knowledge of potentially fatal consequences, warrants a medical diagnosis, and treatment is strongly indicated. Available behavioral and pharmacological treatments are supported by scientific evidence but are vastly underutilized. Discovery of additional medications, with a favorable balance of efficacy versus safety and tolerability can improve clinical uptake of treatment, allow personalized treatment, and improve outcomes. Here, we delineate the clinical conditions when pharmacotherapy should be considered in relation to the main diagnostic systems in use and discuss clinical endpoints that represent meaningful clinical benefits. We then review specific developments in three categories of targets that show promise for expanding the treatment toolkit. GPCRs remain the largest category of successful drug targets across contemporary medicine, and several GPCR targets are currently pursued for alcohol-related indications. Endocrine systems are another established category, and several promising targets have emerged for alcohol indications. Finally, immune modulators have revolutionized treatment of multiple medical conditions, and they may also hold potential to produce benefits in patients with alcohol problems.
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Affiliation(s)
- Markus Heilig
- Center for Social and Affective Neuroscience, Linköping University, and Department of Psychiatry, Linköping University Hospital, Linköping, Sweden
| | - Katie Witkiewitz
- Department of Psychology and Center on Alcohol, Substance Use and Addictions, University of New Mexico, Albuquerque, New Mexico, USA
| | - Lara A. Ray
- Department of Psychology, UCLA, Los Angeles, California, USA
| | - Lorenzo Leggio
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, NIH, Baltimore and Bethesda, Maryland, USA
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Dilly GA, Blednov YA, Warden AS, Ezerskiy L, Fleischer C, Plotkin JD, Patil S, Osterndorff-Kahanek EA, Mayfield J, Mayfield RD, Homanics GE, Messing RO. Knockdown of Tlr3 in dorsal striatum reduces ethanol consumption and acute functional tolerance in male mice. Brain Behav Immun 2024; 118:437-448. [PMID: 38499210 PMCID: PMC11007683 DOI: 10.1016/j.bbi.2024.03.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 03/05/2024] [Accepted: 03/15/2024] [Indexed: 03/20/2024] Open
Abstract
Systemic activation of toll-like receptor 3 (TLR3) signaling using poly(I:C), a TLR3 agonist, drives ethanol consumption in several rodent models, while global knockout of Tlr3 reduces drinking in C57BL/6J male mice. To determine if brain TLR3 pathways are involved in drinking behavior, we used CRISPR/Cas9 genome editing to generate a Tlr3 floxed (Tlr3F/F) mouse line. After sequence confirmation and functional validation of Tlr3 brain transcripts, we injected Tlr3F/F male mice with an adeno-associated virus expressing Cre recombinase (AAV5-CMV-Cre-GFP) to knockdown Tlr3 in the medial prefrontal cortex, nucleus accumbens, or dorsal striatum (DS). Only Tlr3 knockdown in the DS decreased two-bottle choice, every-other-day (2BC-EOD) ethanol consumption. DS-specific deletion of Tlr3 also increased intoxication and prevented acute functional tolerance to ethanol. In contrast, poly(I:C)-induced activation of TLR3 signaling decreased intoxication in male C57BL/6J mice, consistent with its ability to increase 2BC-EOD ethanol consumption in these mice. We also found that TLR3 was highly colocalized with DS neurons. AAV5-Cre transfection occurred predominantly in neurons, but there was minimal transfection in astrocytes and microglia. Collectively, our previous and current studies show that activating or inhibiting TLR3 signaling produces opposite effects on acute responses to ethanol and on ethanol consumption. While previous studies, however, used global knockout or systemic TLR3 activation (which alter peripheral and brain innate immune responses), the current results provide new evidence that brain TLR3 signaling regulates ethanol drinking. We propose that activation of TLR3 signaling in DS neurons increases ethanol consumption and that a striatal TLR3 pathway is a potential target to reduce excessive drinking.
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Affiliation(s)
- Geoffrey A Dilly
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Institute for Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neurology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, United States
| | - Yuri A Blednov
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States
| | - Anna S Warden
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States
| | - Lubov Ezerskiy
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States
| | - Caleb Fleischer
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States
| | - Jesse D Plotkin
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States
| | - Shruti Patil
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States
| | | | - Jody Mayfield
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States
| | - R Dayne Mayfield
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States
| | - Gregg E Homanics
- Departments of Anesthesiology & Perioperative Medicine, Neurobiology, and Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, United States
| | - Robert O Messing
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, United States; Institute for Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, United States; Department of Neurology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, United States.
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5
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Berríos-Cárcamo P, Núñez S, Castañeda J, Gallardo J, Bono MR, Ezquer F. Two-Month Voluntary Ethanol Consumption Promotes Mild Neuroinflammation in the Cerebellum but Not in the Prefrontal Cortex, Hippocampus, or Striatum of Mice. Int J Mol Sci 2024; 25:4173. [PMID: 38673763 PMCID: PMC11050159 DOI: 10.3390/ijms25084173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 03/29/2024] [Accepted: 04/05/2024] [Indexed: 04/28/2024] Open
Abstract
Chronic ethanol exposure often triggers neuroinflammation in the brain's reward system, potentially promoting the drive for ethanol consumption. A main marker of neuroinflammation is the microglia-derived monocyte chemoattractant protein 1 (MCP1) in animal models of alcohol use disorder in which ethanol is forcefully given. However, there are conflicting findings on whether MCP1 is elevated when ethanol is taken voluntarily, which challenges its key role in promoting motivation for ethanol consumption. Here, we studied MCP1 mRNA levels in areas implicated in consumption motivation-specifically, the prefrontal cortex, hippocampus, and striatum-as well as in the cerebellum, a brain area highly sensitive to ethanol, of C57BL/6 mice subjected to intermittent and voluntary ethanol consumption for two months. We found a significant increase in MCP1 mRNA levels in the cerebellum of mice that consumed ethanol compared to controls, whereas no significant changes were observed in the prefrontal cortex, hippocampus, or striatum or in microglia isolated from the hippocampus and striatum. To further characterize cerebellar neuroinflammation, we measured the expression changes in other proinflammatory markers and chemokines, revealing a significant increase in the proinflammatory microRNA miR-155. Notably, other classical proinflammatory markers, such as TNFα, IL6, and IL-1β, remained unaltered, suggesting mild neuroinflammation. These results suggest that the onset of neuroinflammation in motivation-related areas is not required for high voluntary consumption in C57BL/6 mice. In addition, cerebellar susceptibility to neuroinflammation may be a trigger to the cerebellar degeneration that occurs after chronic ethanol consumption in humans.
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Affiliation(s)
- Pablo Berríos-Cárcamo
- Center for Regenerative Medicine, Faculty of Medicine, Clínica Alemana-Universidad del Desarrollo, Santiago 7610615, Chile; (J.G.); (F.E.)
| | - Sarah Núñez
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Sede Los Leones 7510602, Chile;
- Centro Ciencia & Vida, Santiago 8580702, Chile
| | - Justine Castañeda
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile; (J.C.); (M.R.B.)
| | - Javiera Gallardo
- Center for Regenerative Medicine, Faculty of Medicine, Clínica Alemana-Universidad del Desarrollo, Santiago 7610615, Chile; (J.G.); (F.E.)
| | - María Rosa Bono
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile; (J.C.); (M.R.B.)
| | - Fernando Ezquer
- Center for Regenerative Medicine, Faculty of Medicine, Clínica Alemana-Universidad del Desarrollo, Santiago 7610615, Chile; (J.G.); (F.E.)
- Research Center for the Development of Novel Therapeutics Alternatives for Alcohol Use Disorders, Santiago 7610658, Chile
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Donlon J, Kumari P, Varghese SP, Bai M, Florentin OD, Frost ED, Banks J, Vadlapatla N, Kam O, Shad MU, Rahman S, Abulseoud OA, Stone TW, Koola MM. Integrative Pharmacology in the Treatment of Substance Use Disorders. J Dual Diagn 2024; 20:132-177. [PMID: 38117676 DOI: 10.1080/15504263.2023.2293854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
The detrimental physical, mental, and socioeconomic effects of substance use disorders (SUDs) have been apparent to the medical community for decades. However, it has become increasingly urgent in recent years to develop novel pharmacotherapies to treat SUDs. Currently, practitioners typically rely on monotherapy. Monotherapy has been shown to be superior to no treatment at all for most substance classes. However, many randomized controlled trials (RCTs) have revealed that monotherapy leads to poorer outcomes when compared with combination treatment in all specialties of medicine. The results of RCTs suggest that monotherapy frequently fails since multiple dysregulated pathways, enzymes, neurotransmitters, and receptors are involved in the pathophysiology of SUDs. As such, research is urgently needed to determine how various neurobiological mechanisms can be targeted by novel combination treatments to create increasingly specific yet exceedingly comprehensive approaches to SUD treatment. This article aims to review the neurobiology that integrates many pathophysiologic mechanisms and discuss integrative pharmacology developments that may ultimately improve clinical outcomes for patients with SUDs. Many neurobiological mechanisms are known to be involved in SUDs including dopaminergic, nicotinic, N-methyl-D-aspartate (NMDA), and kynurenic acid (KYNA) mechanisms. Emerging evidence indicates that KYNA, a tryptophan metabolite, modulates all these major pathophysiologic mechanisms. Therefore, achieving KYNA homeostasis by harmonizing integrative pathophysiology and pharmacology could prove to be a better therapeutic approach for SUDs. We propose KYNA-NMDA-α7nAChRcentric pathophysiology, the "conductor of the orchestra," as a novel approach to treat many SUDs concurrently. KYNA-NMDA-α7nAChR pathophysiology may be the "command center" of neuropsychiatry. To date, extant RCTs have shown equivocal findings across comparison conditions, possibly because investigators targeted single pathophysiologic mechanisms, hit wrong targets in underlying pathophysiologic mechanisms, and tested inadequate monotherapy treatment. We provide examples of potential combination treatments that simultaneously target multiple pathophysiologic mechanisms in addition to KYNA. Kynurenine pathway metabolism demonstrates the greatest potential as a target for neuropsychiatric diseases. The investigational medications with the most evidence include memantine, galantamine, and N-acetylcysteine. Future RCTs are warranted with novel combination treatments for SUDs. Multicenter RCTs with integrative pharmacology offer a promising, potentially fruitful avenue to develop novel therapeutics for the treatment of SUDs.
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Affiliation(s)
- Jack Donlon
- Cooper Medical School of Rowan University, Camden, New Jersey, USA
| | - Pooja Kumari
- Community Living Trent Highlands, Peterborough, Canada
| | - Sajoy P Varghese
- Addiction Recovery Treatment Services, Veterans Affairs Northern California Health Care System, University of California, Davis, Sacramento, California, USA
| | - Michael Bai
- Columbia University, New York, New York, USA
| | - Ori David Florentin
- Department of Psychiatry, Westchester Medical Center, Valhalla, New York, USA
| | - Emma D Frost
- Department of Neurology, Cooper University Health Care, Camden, New Jersey, USA
| | - John Banks
- Talkiatry Mental Health Clinic, New York, New York, USA
| | - Niyathi Vadlapatla
- Thomas Jefferson High School for Science and Technology, Alexandria, Virginia, USA
| | - Olivia Kam
- Stony Brook University Renaissance School of Medicine, Stony Brook, New York, USA
| | - Mujeeb U Shad
- Department of Psychiatry, University of Nevada Las Vegas, Las Vegas, Nevada, USA
| | - Shafiqur Rahman
- Department of Pharmaceutical Sciences, College of Pharmacy, South Dakota State University, Brookings, South Dakota, USA
| | - Osama A Abulseoud
- Department of Psychiatry and Psychology, Alix School of Medicine at Mayo Clinic, Phoenix, Arizona, USA
| | - Trevor W Stone
- Nuffield Department of Orthopedics, Rheumatology and Musculoskeletal Sciences (NDORMS), University of Oxford, Oxford, UK
| | - Maju Mathew Koola
- Department of Psychiatry and Behavioral Health, Cooper University Health Care, Cooper Medical School of Rowan University, Camden, New Jersey, USA
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Airapetov M, Eresko S, Ignatova P, Lebedev A, Bychkov E, Shabanov P. Effect of rifampicin on TLR4-signaling pathways in the nucleus accumbens of the rat brain during abstinence of long-term alcohol treatment. Alcohol Alcohol 2024; 59:agae016. [PMID: 38520481 DOI: 10.1093/alcalc/agae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/03/2024] [Accepted: 02/19/2024] [Indexed: 03/25/2024] Open
Abstract
AIMS The treatment with the antibiotic rifampicin (Rif) led to a decrease in the frequency of neurodegenerative pathologies. There are suggestions that the mechanism of action of Rif may be mediated by its effect on toll-like receptor (TLR)4-dependent pathways. We evaluated the expression status of TLR4-dependent genes during abstinence from long-term alcohol treatments in the nucleus accumbens (NAc) of the rat brain, and also studied the effects of Rif to correct these changes. METHODS The long-term alcohol treatment was performed by intragastric delivery of ethanol solution. At the end of alcohol treatment intraperitoneal injections of Rif (100 mg/kg) or saline were made. Extraction of the brain structures was performed on the 10th day of abstinence from alcohol. We used the SYBR Green qPCR method to quantitatively analyze the relative expression levels of the studied genes. RESULTS The long-term alcohol treatment promotes an increase in the level of TLR4 mRNA and mRNA of its endogenous ligand high-mobility group protein B1 during abstinence drop alcohol in NAc of rats. The use of Rif in our study led to a decrease in the increased expression of high-mobility group protein B1, Tlr4, and proinflammatory cytokine genes (Il1β, Il6) in the NAc of the rat brain during abstinence of long-term alcohol treatment. In addition, Rif administration increased the decreased mRNA levels of anti-inflammatory cytokines (Il10, Il11). CONCLUSION The data obtained indicate the ability of Rif to correct the mechanisms of the TLR4 system genes in the NAc of the rat brain during alcohol abstinence.
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Affiliation(s)
- Marat Airapetov
- Department of Neuropharmacology, Institute of Experimental Medicine, P.O. Box 197376, 12 Academician Pavlova str., St. Petersburg, Russian Federation
- Department of Pathological Physiology, Military Medical Academy of S.M. Kirov, P.O. Box 194044, 6G Akademika Lebedeva str., St. Petersburg, Russian Federation
| | - Sergei Eresko
- Department of Neuropharmacology, Institute of Experimental Medicine, P.O. Box 197376, 12 Academician Pavlova str., St. Petersburg, Russian Federation
- Center for Chemical Engineering, Saint-Petersburg National Research University of Information Technologies, Mechanics and Optics, P.O. Box 197101, 49 Kronverksky pr., St. Petersburg, Russian Federation
| | - Polina Ignatova
- Department of Neuropharmacology, Institute of Experimental Medicine, P.O. Box 197376, 12 Academician Pavlova str., St. Petersburg, Russian Federation
| | - Andrei Lebedev
- Department of Neuropharmacology, Institute of Experimental Medicine, P.O. Box 197376, 12 Academician Pavlova str., St. Petersburg, Russian Federation
| | - Evgenii Bychkov
- Department of Neuropharmacology, Institute of Experimental Medicine, P.O. Box 197376, 12 Academician Pavlova str., St. Petersburg, Russian Federation
| | - Petr Shabanov
- Department of Neuropharmacology, Institute of Experimental Medicine, P.O. Box 197376, 12 Academician Pavlova str., St. Petersburg, Russian Federation
- Department of Pathological Physiology, Military Medical Academy of S.M. Kirov, P.O. Box 194044, 6G Akademika Lebedeva str., St. Petersburg, Russian Federation
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Crews FT, Macht V, Vetreno RP. Epigenetic regulation of microglia and neurons by proinflammatory signaling following adolescent intermittent ethanol (AIE) exposure and in human AUD. ADVANCES IN DRUG AND ALCOHOL RESEARCH 2024; 4:12094. [PMID: 38524847 PMCID: PMC10957664 DOI: 10.3389/adar.2024.12094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 02/05/2024] [Indexed: 03/26/2024]
Abstract
Adolescent alcohol drinking is linked to high rates of adult alcohol problems and alcohol use disorder (AUD). The Neurobiology of Alcohol Drinking in Adulthood (NADIA) consortium adolescent intermittent ethanol (AIE) models adolescent binge drinking, followed by abstinent maturation to adulthood to determine the persistent AIE changes in neurobiology and behavior. AIE increases adult alcohol drinking and preference, increases anxiety and reward seeking, and disrupts sleep and cognition, all risks for AUD. In addition, AIE induces changes in neuroimmune gene expression in neurons and glia that alter neurocircuitry and behavior. HMGB1 is a unique neuroimmune signal released from neurons and glia by ethanol that activates multiple proinflammatory receptors, including Toll-like receptors (TLRs), that spread proinflammatory gene induction. HMGB1 expression is increased by AIE in rat brain and in post-mortem human AUD brain, where it correlates with lifetime alcohol consumption. HMGB1 activation of TLR increase TLR expression. Human AUD brain and rat brain following AIE show increases in multiple TLRs. Brain regional differences in neurotransmitters and cell types impact ethanol responses and neuroimmune gene induction. Microglia are monocyte-like cells that provide trophic and synaptic functions, that ethanol proinflammatory signals sensitize or "prime" during repeated drinking cycles, impacting neurocircuitry. Neurocircuits are differently impacted dependent upon neuronal-glial signaling. Acetylcholine is an anti-inflammatory neurotransmitter. AIE increases HMGB1-TLR4 signaling in forebrain, reducing cholinergic neurons by silencing multiple cholinergic defining genes through upregulation of RE-1 silencing factor (REST), a transcription inhibitor known to regulate neuronal differentiation. HMGB1 REST induction reduces cholinergic neurons in basal forebrain and cholinergic innervation of hippocampus. Adult brain hippocampal neurogenesis is regulated by a neurogenic niche formed from multiple cells. In vivo AIE and in vitro studies find ethanol increases HMGB1-TLR4 signaling and other proinflammatory signaling as well as reducing trophic factors, NGF, and BDNF, coincident with loss of the cholinergic synapse marker vChAT. These changes in gene expression-transcriptomes result in reduced adult neurogenesis. Excitingly, HMGB1 antagonists, anti-inflammatories, and epigenetic modifiers like histone deacetylase inhibitors restore trophic the neurogenesis. These findings suggest anti-inflammatory and epigenetic drugs should be considered for AUD therapy and may provide long-lasting reversal of psychopathology.
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Affiliation(s)
- Fulton T. Crews
- Departments of Pharmacology and Psychiatry, Bowles Center for Alcohol Studies, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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9
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Grodin EN. Neuroimmune modulators as novel pharmacotherapies for substance use disorders. Brain Behav Immun Health 2024; 36:100744. [PMID: 38435721 PMCID: PMC10906159 DOI: 10.1016/j.bbih.2024.100744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 12/20/2023] [Accepted: 02/20/2024] [Indexed: 03/05/2024] Open
Abstract
One promising avenue of research is the use of neuroimmune modulators to treat substance use disorders (SUDs). Neuroimmune modulators target the interactions between the nervous system and immune system, which have been found to play a crucial role in the development and maintenance of SUDs. Multiple classes of substances produce alterations to neuroimmune signaling and peripheral immune function, including alcohol, opioids, and psychostimulants Preclinical studies have shown that neuroimmune modulators can reduce drug-seeking behavior and prevent relapse in animal models of SUDs. Additionally, early-phase clinical trials have demonstrated the safety and feasibility of using neuroimmune modulators as a treatment for SUDs in humans. These therapeutics can be used as stand-alone treatments or as adjunctive. This review summarizes the current state of the field and provides future directions with a specific focus on personalized medicine.
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Affiliation(s)
- Erica N. Grodin
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA
- Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA, USA
- Cousins Center for Psychoneuroimmunology, University of California at Los Angeles, Los Angeles, CA, USA
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Lin X, Li X, Li C, Wang H, Zou L, Pan J, Zhang X, He L, Rong X, Peng Y. Activation of STING signaling aggravates chronic alcohol exposure-induced cognitive impairment by increasing neuroinflammation and mitochondrial apoptosis. CNS Neurosci Ther 2024; 30:e14689. [PMID: 38516831 PMCID: PMC10958405 DOI: 10.1111/cns.14689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/18/2024] [Accepted: 03/11/2024] [Indexed: 03/23/2024] Open
Abstract
AIMS Chronic alcohol exposure leads to persistent neurological disorders, which are mainly attributed to neuroinflammation and apoptosis. Stimulator of IFN genes (STING) is essential in the cytosolic DNA sensing pathway and is involved in inflammation and cellular death processes. This study was to examine the expression pattern and biological functions of STING signaling in alcohol use disorder (AUD). METHODS Cell-free DNA was extracted from human and mouse plasma. C57BL/6J mice were given alcohol by gavage for 28 days, and behavior tests were used to determine their mood and cognition. Cultured cells were treated with ethanol for 24 hours. The STING agonist DMXAA, STING inhibitor C-176, and STING-siRNA were used to intervene the STING. qPCR, western blot, and immunofluorescence staining were used to assess STING signaling, inflammation, and apoptosis. RESULTS Circulating cell-free mitochondrial DNA (mtDNA) was increased in individuals with AUD and mice chronically exposed to alcohol. Upregulation of STING signaling under alcohol exposure led to inflammatory responses in BV2 cells and mitochondrial apoptosis in PC12 cells. DMXAA exacerbated alcohol-induced cognitive impairment and increased the activation of microglia, neuroinflammation, and apoptosis in the medial prefrontal cortex (mPFC), while C-176 exerted neuroprotection. CONCLUSION Activation of STING signaling played an essential role in alcohol-induced inflammation and mitochondrial apoptosis in the mPFC. This study identifies STING as a promising therapeutic target for AUD.
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Affiliation(s)
- Xinrou Lin
- Department of Neurology, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
- Nanhai Translational Innovation Center of Precision ImmunologySun Yat‐Sen Memorial HospitalFoshanChina
| | - Xiangpen Li
- Department of Neurology, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
- Shenshan Medical Center, Sun Yat‐sen Memorial HospitalSun Yat‐sen UniversityShanweiChina
| | - Chenguang Li
- Department of Neurology, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
| | - Hongxuan Wang
- Department of Neurology, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
| | - Lubin Zou
- Department of Neurology, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
- Nanhai Translational Innovation Center of Precision ImmunologySun Yat‐Sen Memorial HospitalFoshanChina
| | - Jingrui Pan
- Department of Neurology, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
- Shenshan Medical Center, Sun Yat‐sen Memorial HospitalSun Yat‐sen UniversityShanweiChina
| | - Xiaoni Zhang
- Department of Neurology, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
| | - Lei He
- Department of Neurology, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
| | - Xiaoming Rong
- Department of Neurology, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
| | - Ying Peng
- Department of Neurology, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
- Nanhai Translational Innovation Center of Precision ImmunologySun Yat‐Sen Memorial HospitalFoshanChina
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat‐Sen Memorial HospitalSun Yat‐Sen UniversityGuangzhouChina
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Perpiñá-Clérigues C, Mellado S, Galiana-Roselló C, Fernández-Regueras M, Marcos M, García-García F, Pascual M. Novel insight into the lipid network of plasma extracellular vesicles reveal sex-based differences in the lipidomic profile of alcohol use disorder patients. Biol Sex Differ 2024; 15:10. [PMID: 38273378 PMCID: PMC10809459 DOI: 10.1186/s13293-024-00584-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 01/11/2024] [Indexed: 01/27/2024] Open
Abstract
BACKGROUND Alcohol use disorder (AUD) is one of the most common psychiatric disorders, with the consumption of alcohol considered a leading cause of preventable deaths worldwide. Lipids play a crucial functional role in cell membranes; however, we know little about the role of lipids in extracellular vesicles (EVs) as regulatory molecules and disease biomarkers. METHODS We employed a sensitive lipidomic strategy to characterize lipid species from the plasma EVs of AUD patients to evaluate functional roles and enzymatic activity networks to improve the knowledge of lipid metabolism after alcohol consumption. We analyzed plasma EV lipids from AUD females and males and healthy individuals to highlight lipids with differential abundance and biologically interpreted lipidomics data using LINEX2, which evaluates enzymatic dysregulation using an enrichment algorithm. RESULTS Our results show, for the first time, that AUD females exhibited more significant substrate-product changes in lysophosphatidylcholine/phosphatidylcholine lipids and phospholipase/acyltransferase activity, which are potentially linked to cancer progression and neuroinflammation. Conversely, AUD males suffer from dysregulated ceramide and sphingomyelin lipids involving sphingomyelinase, sphingomyelin phosphodiesterase, and sphingomyelin synthase activity, which relates to hepatotoxicity. Notably, the analysis of plasma EVs from AUD females and males demonstrates enrichment of lipid ontology terms associated with "negative intrinsic curvature" and "positive intrinsic curvature", respectively. CONCLUSIONS Our methodological developments support an improved understanding of lipid metabolism and regulatory mechanisms, which contribute to the identification of novel lipid targets and the discovery of sex-specific clinical biomarkers in AUD.
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Affiliation(s)
- Carla Perpiñá-Clérigues
- Computational Biomedicine Laboratory, Príncipe Felipe Research Center, C/Eduardo Primo Yúfera, 3, 46012, Valencia, Spain
- Department of Physiology, School of Medicine and Dentistry, University of Valencia, Avda. Blasco Ibáñez, 15, 46010, Valencia, Spain
| | - Susana Mellado
- Department of Physiology, School of Medicine and Dentistry, University of Valencia, Avda. Blasco Ibáñez, 15, 46010, Valencia, Spain
| | - Cristina Galiana-Roselló
- Department of Inorganic Chemistry, Institute of Molecular Science, University of Valencia, 46980, Paterna, Spain
| | - María Fernández-Regueras
- Hospital Universitario de Burgos, 09006, Burgos, Spain
- Hospital Universitario de Salamanca, 37007, Salamanca, Spain
| | - Miguel Marcos
- Department of Internal Medicine, University Hospital of Salamanca, University of Salamanca, Institute of Biomedical Research of Salamanca (IBSAL), 37007, Salamanca, Spain
| | - Francisco García-García
- Computational Biomedicine Laboratory, Príncipe Felipe Research Center, C/Eduardo Primo Yúfera, 3, 46012, Valencia, Spain.
| | - María Pascual
- Department of Physiology, School of Medicine and Dentistry, University of Valencia, Avda. Blasco Ibáñez, 15, 46010, Valencia, Spain.
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Diaz LA, Winder GS, Leggio L, Bajaj JS, Bataller R, Arab JP. New insights into the molecular basis of alcohol abstinence and relapse in alcohol-associated liver disease. Hepatology 2023:01515467-990000000-00605. [PMID: 37862466 DOI: 10.1097/hep.0000000000000645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 10/11/2023] [Indexed: 10/22/2023]
Abstract
Alcohol use disorder remains a significant public health concern, affecting around 5% of adults worldwide. Novel pathways of damage have been described during the last years, providing insight into the mechanism of injury due to alcohol misuse beyond the direct effect of ethanol byproducts on the liver parenchyma and neurobehavioral mechanisms. Thus, the gut-liver-brain axis and immune system involvement could be therapeutic targets for alcohol use disorder. In particular, changes in gut microbiota composition and function, and bile acid homeostasis, have been shown with alcohol consumption and cessation. Alcohol can also directly disrupt intestinal and blood-brain barriers. Activation of the immune system can be triggered by intestinal barrier dysfunction and translocation of bacteria, pathogen-associated molecular patterns (such as lipopolysaccharide), cytokines, and damage-associated molecular patterns. These factors, in turn, promote liver and brain inflammation and the progression of liver fibrosis. Other involved mechanisms include oxidative stress, apoptosis, autophagy, and the release of extracellular vesicles and miRNA from hepatocytes. Potential therapeutic targets include gut microbiota (probiotics and fecal microbiota transplantation), neuroinflammatory pathways, as well as neuroendocrine pathways, for example, the ghrelin system (ghrelin receptor blockade), incretin mimetics (glucagon-like peptide-1 analogs), and the mineralocorticoid receptor system (spironolactone). In addition, support with psychological and behavioral treatments is essential to address the multiple dimensions of alcohol use disorder. In the future, a personalized approach considering these novel targets can contribute to significantly decreasing the alcohol-associated burden of disease.
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Affiliation(s)
- Luis Antonio Diaz
- Departamento de Gastroenterología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | - Lorenzo Leggio
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institutes of Health, NIDA and NIAAA, Baltimore, Maryland, USA
| | - Jasmohan S Bajaj
- Division of Gastroenterology, Hepatology, and Nutrition, Virginia Commonwealth University and Central Virginia Veterans Health Care System, Richmond, Virginia, USA
| | - Ramon Bataller
- Liver Unit, Hospital Clinic, Institut d'Investigacions August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Juan Pablo Arab
- Departamento de Gastroenterología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Department of Medicine, Division of Gastroenterology, Schulich School of Medicine, Western University, London, Ontario, Canada
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Khan MAS, Chang SL. Alcohol and the Brain-Gut Axis: The Involvement of Microglia and Enteric Glia in the Process of Neuro-Enteric Inflammation. Cells 2023; 12:2475. [PMID: 37887319 PMCID: PMC10605902 DOI: 10.3390/cells12202475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 09/25/2023] [Accepted: 10/11/2023] [Indexed: 10/28/2023] Open
Abstract
Binge or chronic alcohol consumption causes neuroinflammation and leads to alcohol use disorder (AUD). AUD not only affects the central nervous system (CNS) but also leads to pathologies in the peripheral and enteric nervous systems (ENS). Thus, understanding the mechanism of the immune signaling to target the effector molecules in the signaling pathway is necessary to alleviate AUD. Growing evidence shows that excessive alcohol consumption can activate neuroimmune cells, including microglia, and change the status of neurotransmitters, affecting the neuroimmune system. Microglia, like peripheral macrophages, are an integral part of the immune defense and represent the reticuloendothelial system in the CNS. Microglia constantly survey the CNS to scavenge the neuronal debris. These cells also protect parenchymal cells in the brain and spinal cord by repairing nerve circuits to keep the nervous system healthy against infectious and stress-derived agents. In an activated state, they become highly dynamic and mobile and can modulate the levels of neurotransmitters in the CNS. In several ways, microglia, enteric glial cells, and macrophages are similar in terms of causing inflammation. Microglia also express most of the receptors that are constitutively present in macrophages. Several receptors on microglia respond to the inflammatory signals that arise from danger-associated molecular patterns (DAMPs), pathogen-associated molecular patterns (PAMPs), endotoxins (e.g., lipopolysaccharides), and stress-causing molecules (e.g., alcohol). Therefore, this review article presents the latest findings, describing the roles of microglia and enteric glial cells in the brain and gut, respectively, and their association with neurotransmitters, neurotrophic factors, and receptors under the influence of binge and chronic alcohol use, and AUD.
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Affiliation(s)
- Mohammed A. S. Khan
- Department of Neurosurgery, Brigham Hospital for Children, Harvard Medical School, Boston, MA 02115, USA;
| | - Sulie L. Chang
- Institute of NeuroImmune Pharmacology, Seton Hall University, South Orange, NJ 07079, USA
- Department of Biological Sciences, Seton Hall University, South Orange, NJ 07079, USA
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14
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Burnette EM, Grodin EN, Olmstead R, Ray LA, Irwin MR. Alcohol use disorder (AUD) is associated with enhanced sensitivity to cellular lipopolysaccharide challenge. ALCOHOL, CLINICAL & EXPERIMENTAL RESEARCH 2023; 47:1859-1868. [PMID: 37864529 PMCID: PMC10830126 DOI: 10.1111/acer.15173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 08/02/2023] [Accepted: 08/09/2023] [Indexed: 10/23/2023]
Abstract
BACKGROUND Inflammation has been associated with alcohol use disorder (AUD). A novel method to characterize AUD-related immune signaling involves probing Toll-like receptor (TLR)-4 stimulated monocyte production of intracellular cytokines (ICCs) via lipopolysaccharide (LPS). We evaluated relationships between AUD and ICC production at rest and after LPS stimulation. METHODS We analyzed blood samples from 36 participants (AUD N = 14; Controls N = 22), collected across time, with ICC expression assessed at rest (i.e., unstimulated) and following stimulation with LPS (i.e., a total of 5 repeated unstimulated or stimulated measures/participant). Markers assessed included tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), TNF-α and IL-6 co-expression, and interferon (IFN). For each marker, we constructed linear mixed models with AUD, LPS, and timepoint as fixed effects (BMI as covariate), allowing for random slope and intercept. AUD × LPS was included as an interaction. RESULTS For TLR4-stimulated monocyte production of TNF-α, there were effects of AUD (p < 0.01), LPS (p < 0.001), and AUD × LPS interaction (p < 0.05), indicating that individuals with AUD showed greater unstimulated- and stimulated monocyte expression of TNF-α. Similarly, for TLR4-stimulated monocyte co-expression of TNF-α and IL-6, there were effects of AUD (p < 0.01), LPS (p < 0.001), and AUD × LPS interaction (p < 0.05). No AUD or LPS effects were found for IL-6. Timepoint effects were observed on IL-6 and TNF-α/IL-6 co-expression (p < 0.001). Finally, for IFN there were also effects of AUD (p < 0.05), LPS (p < 0.001), and AUD × LPS (p < 0.001). CONCLUSIONS Individuals with AUD showed greater resting or unstimulated levels of intracellular monocyte expression of TNF-α and IL-6/TNF-α co-expression than controls. AUD was associated with increases in TLR4-stimulated monocyte production of TNF-α and co-production of IL-6 and TNF-α. This is, to our knowledge, the first study to investigate relationships between AUD and monocyte production of proinflammatory cytokines, at rest and in response to TLR4 stimulation with LPS. The study extends previous findings on the roles of proinflammatory cytokines in AUD and serves as a critical proof of concept for the use of this method to probe neuroimmune mechanisms underlying AUD.
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Affiliation(s)
- Elizabeth M. Burnette
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
- Neuroscience Interdepartmental Program, University of California at Los Angeles, Los Angeles, CA
| | - Erica N. Grodin
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
| | - Richard Olmstead
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA
- Jane and Terry Semel Institute for Neuroscience and Human Behavior, University of California at Los Angeles, Los Angeles, CA
- Cousins Center for Psychoneuroimmunology, University of California at Los Angeles, Los Angeles, CA
| | - Lara A. Ray
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
- Neuroscience Interdepartmental Program, University of California at Los Angeles, Los Angeles, CA
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA
| | - Michael R. Irwin
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA
- Jane and Terry Semel Institute for Neuroscience and Human Behavior, University of California at Los Angeles, Los Angeles, CA
- Cousins Center for Psychoneuroimmunology, University of California at Los Angeles, Los Angeles, CA
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15
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Atkinson NS. The Role of Toll and Nonnuclear NF-κB Signaling in the Response to Alcohol. Cells 2023; 12:1508. [PMID: 37296629 PMCID: PMC10252657 DOI: 10.3390/cells12111508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 05/23/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023] Open
Abstract
An understanding of neuroimmune signaling has become central to a description of how alcohol causes addiction and how it damages people with an AUD. It is well known that the neuroimmune system influences neural activity via changes in gene expression. This review discusses the roles played by CNS Toll-like receptor (TLR) signaling in the response to alcohol. Also discussed are observations in Drosophila that show how TLR signaling pathways can be co-opted by the nervous system and potentially shape behavior to a far greater extent and in ways different than generally recognized. For example, in Drosophila, TLRs substitute for neurotrophin receptors and an NF-κB at the end of a TLR pathway influences alcohol responsivity by acting non-genomically.
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Affiliation(s)
- Nigel S Atkinson
- Department of Neuroscience and The Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, TX 78712, USA
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16
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Grodin EN, Meredith LR, Burnette EM, Miotto K, Irwin MR, Ray LA. Baseline C-reactive protein levels are predictive of treatment response to a neuroimmune modulator in individuals with an alcohol use disorder: a preliminary study. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2023; 49:333-344. [PMID: 36282988 PMCID: PMC10840759 DOI: 10.1080/00952990.2022.2124918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 09/07/2022] [Accepted: 09/12/2022] [Indexed: 01/25/2023]
Abstract
Background: Inflammation is implicated in alcohol use disorder (AUD). Ibudilast, a neuroimmune modulator, shows promise for the treatment of AUD. Elevated inflammation, indicated by high levels of C-reactive protein (CRP), represents a possible subtype of AUD, which may be associated with treatment response to ibudilast.Objectives: The current study evaluated CRP as a predictor of treatment response to ibudilast; hypothesizing that ibudilast would be more effective at reducing drinking and alcohol cue-reactivity in individuals with higher CRP levels.Methods: This is a secondary analysis of a clinical trial of ibudilast for AUD, which found that ibudilast reduced heavy drinking in individuals with AUD. Fifty-one individuals were randomized to receive ibudilast (n = 24 [16 M/8F]) or placebo (n = 27 [18 M/9F]) for two weeks. Participants provided blood samples at baseline to assess CRP levels, completed daily assessments of alcohol use, and an fMRI alcohol cue-reactivity task at study mid-point. Models tested the effects of medication, CRP levels, and their interaction on drinks per drinking day and alcohol cue-reactivity.Results: There was a significant interaction between medication and CRP (F = 3.80, p = .03), such that the ibudilast high CRP group had fewer drinks per drinking day compared to the ibudilast low CRP group. CRP moderated the effect of medication on brain activation in a cluster extending from the left inferior frontal gyrus to the right-dorsal striatum (Z = 4.55, p < .001). This interaction was driven by attenuated cue-reactivity in the ibudilast high CRP group relative to the ibudilast low CRP and placebo high CRP groups.Conclusions: This study serves as an initial investigation into predictors of clinical response to ibudilast treatment and suggests that a baseline proinflammatory profile may enhance clinical efficacy.
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Affiliation(s)
- Erica N. Grodin
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
| | - Lindsay R. Meredith
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
| | - Elizabeth M. Burnette
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
- Neuroscience Interdepartmental Program, University of California at Los Angeles, Los Angeles, CA
| | - Karen Miotto
- Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA
| | - Michael R. Irwin
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
- Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA
- Jane & Terry Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA
- Cousins Center for Psychoneuroimmunology, University of California at Los Angeles, Los Angeles, CA
| | - Lara A. Ray
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
- Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA
- Brain Research Institute, University of California, Los Angeles, CA
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17
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Battista JT, Piacentino D, Schwandt ML, Lee MR, Faulkner ML, Farokhnia M, Leggio L. Investigating the relationship between early life adversity, inflammation and alcohol use. Addict Biol 2023; 28:e13274. [PMID: 37186442 PMCID: PMC10214493 DOI: 10.1111/adb.13274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 01/30/2023] [Accepted: 03/19/2023] [Indexed: 05/17/2023]
Abstract
Early life adversity (ELA) has long-lasting and potentially harmful effects on adult mental and physical health, including a higher likelihood of developing psychiatric conditions such as depression, anxiety and alcohol use disorder (AUD). It has been suggested that inflammation may play a role in linking ELA to the development of AUD. Here, we evaluated a number of predictive factors of high sensitivity C-reactive protein (hsCRP), a key inflammatory marker, and the potential mediating role of hsCRP in the relationship between ELA and alcohol misuse in adulthood. Data was collected from participants who participated in NIAAA screening protocols between January 2013 and December 2019. In this secondary analysis, we first tested, via multiple linear regression, potential predictors of hsCRP levels among adults with AUD (N = 781) and non-AUD (N = 440) individuals. We subsequently conducted mediation analyses to evaluate the potential role of hsCRP in the relationship between early life stress and alcohol use. Regression analysis showed that stress in early life, but not childhood trauma, significantly predicted increased hsCRP levels in adulthood (p < 0.05). Additionally, a greater amount of alcohol drinking, but not a diagnosis of AUD, significantly predicted increased hsCRP levels (p < 0.05). Furthermore, hsCRP mediated the relationship between early life stress and alcohol consumption. Early life stress and heavier alcohol drinking both predicted increased hsCRP levels; however, an AUD diagnosis did not. Elevated inflammation, due to and/or predicted by greater early life stress, may contribute to the development of unhealthy alcohol use in adulthood.
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Affiliation(s)
- Jillian T. Battista
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore and Bethesda, MD, USA
| | - Daria Piacentino
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore and Bethesda, MD, USA
- Center on Compulsive Behaviors, National Institutes of Health, Bethesda, MD, USA
| | - Melanie L. Schwandt
- Office of the Clinical Director, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Mary R. Lee
- Veterans Affairs Medical Center, Washington, DC
| | - Monica L. Faulkner
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore and Bethesda, MD, USA
| | - Mehdi Farokhnia
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore and Bethesda, MD, USA
- Center on Compulsive Behaviors, National Institutes of Health, Bethesda, MD, USA
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Lorenzo Leggio
- Clinical Psychoneuroendocrinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program and National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Biological Research, National Institutes of Health, Baltimore and Bethesda, MD, USA
- Center on Compulsive Behaviors, National Institutes of Health, Bethesda, MD, USA
- Medication Development Program, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
- Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, School of Public Health, Brown University, Providence, RI, USA
- Division of Addiction Medicine, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
- Department of Neuroscience, Georgetown University Medical Center, Washington DC, USA
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18
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Varodayan FP, Pahng AR, Davis TD, Gandhi P, Bajo M, Steinman MQ, Kiosses WB, Blednov YA, Burkart MD, Edwards S, Roberts AJ, Roberto M. Chronic ethanol induces a pro-inflammatory switch in interleukin-1β regulation of GABAergic signaling in the medial prefrontal cortex of male mice. Brain Behav Immun 2023; 110:125-139. [PMID: 36863493 PMCID: PMC10106421 DOI: 10.1016/j.bbi.2023.02.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 02/20/2023] [Accepted: 02/25/2023] [Indexed: 03/04/2023] Open
Abstract
Neuroimmune pathways regulate brain function to influence complex behavior and play a role in several neuropsychiatric diseases, including alcohol use disorder (AUD). In particular, the interleukin-1 (IL-1) system has emerged as a key regulator of the brain's response to ethanol (alcohol). Here we investigated the mechanisms underlying ethanol-induced neuroadaptation of IL-1β signaling at GABAergic synapses in the prelimbic region of the medial prefrontal cortex (mPFC), an area responsible for integrating contextual information to mediate conflicting motivational drives. We exposed C57BL/6J male mice to the chronic intermittent ethanol vapor-2 bottle choice paradigm (CIE-2BC) to induce ethanol dependence, and conducted ex vivo electrophysiology and molecular analyses. We found that the IL-1 system regulates basal mPFC function through its actions at inhibitory synapses on prelimbic layer 2/3 pyramidal neurons. IL-1β can selectively recruit either neuroprotective (PI3K/Akt) or pro-inflammatory (MyD88/p38 MAPK) mechanisms to produce opposing synaptic effects. In ethanol naïve conditions, there was a strong PI3K/Akt bias leading to a disinhibition of pyramidal neurons. Ethanol dependence produced opposite IL-1 effects - enhanced local inhibition via a switch in IL-1β signaling to the canonical pro-inflammatory MyD88 pathway. Ethanol dependence also increased cellular IL-1β in the mPFC, while decreasing expression of downstream effectors (Akt, p38 MAPK). Thus, IL-1β may represent a key neural substrate in ethanol-induced cortical dysfunction. As the IL-1 receptor antagonist (kineret) is already FDA-approved for other diseases, this work underscores the high therapeutic potential of IL-1 signaling/neuroimmune-based treatments for AUD.
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Affiliation(s)
- F P Varodayan
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA; Developmental Exposure Alcohol Research Center and Behavioral Neuroscience Program, Department of Psychology, Binghamton University-SUNY, Binghamton, NY, USA
| | - A R Pahng
- Department of Physiology, Louisiana State University Health Sciences Center, New Orleans, LA, USA; Southeast Louisiana Veterans Health Care System, New Orleans, LA, USA
| | - T D Davis
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, CA, USA; Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Binghamton University-SUNY, Binghamton, NY, USA
| | - P Gandhi
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - M Bajo
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - M Q Steinman
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - W B Kiosses
- Microscopy Core Imaging Facility, La Jolla Institute for Immunology, La Jolla, CA 92037, USA
| | - Y A Blednov
- Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, TX 78712, USA
| | - M D Burkart
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - S Edwards
- Department of Physiology, Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | - A J Roberts
- Animal Models Core Facility, The Scripps Research Institute, La Jolla, CA, USA
| | - M Roberto
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA.
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19
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Crews FT, Coleman LG, Macht VA, Vetreno RP. Targeting Persistent Changes in Neuroimmune and Epigenetic Signaling in Adolescent Drinking to Treat Alcohol Use Disorder in Adulthood. Pharmacol Rev 2023; 75:380-396. [PMID: 36781218 PMCID: PMC9969522 DOI: 10.1124/pharmrev.122.000710] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 10/24/2022] [Accepted: 10/28/2022] [Indexed: 12/15/2022] Open
Abstract
Studies universally find early age of drinking onset is linked to lifelong risks of alcohol problems and alcohol use disorder (AUD). Assessment of the lasting effect of drinking during adolescent development in humans is confounded by the diversity of environmental and genetic factors that affect adolescent development, including emerging personality disorders and progressive increases in drinking trajectories into adulthood. Preclinical studies using an adolescent intermittent ethanol (AIE) exposure rat model of underage binge drinking avoid the human confounds and support lifelong changes that increase risks. AIE increases adult alcohol drinking, risky decision-making, reward-seeking, and anxiety as well as reductions in executive function that all increase risks for the development of an AUD. AIE causes persistent increases in brain neuroimmune signaling high-mobility group box 1 (HMGB1), Toll-like receptor, receptor for advanced glycation end products, and innate immune genes that are also found to be increased in human AUD brain. HMGB1 is released from cells by ethanol, both free and within extracellular vesicles, that act on neurons and glia, shifting transcription and cellular phenotype. AIE-induced decreases in adult hippocampal neurogenesis and loss of basal forebrain cholinergic neurons are reviewed as examples of persistent AIE-induced pathology. Both are prevented and reversed by anti-inflammatory and epigenetic drugs. Findings suggest AIE-increased HMGB1 signaling induces the RE-1 silencing transcript blunting cholinergic gene expression, shifting neuronal phenotype. Inhibition of HMGB1 neuroimmune signaling, histone methylation enzymes, and galantamine, the cholinesterase inhibitor, both prevent and reverse AIE pathology. These findings provide new targets that may reverse AUD neuropathology as well as other brain diseases linked to neuroimmune signaling. SIGNIFICANCE STATEMENT: Adolescent underage binge drinking studies find that earlier adolescent drinking is associated with lifelong alcohol problems including high levels of lifetime alcohol use disorder (AUD). Preclinical studies find the underage binge drinking adolescent intermittent ethanol (AIE) model causes lasting changes in adults that increase risks of developing adult alcohol problems. Loss of hippocampal neurogenesis and loss of basal forebrain cholinergic neurons provide examples of how AIE-induced epigenetic and neuroimmune signaling provide novel therapeutic targets for adult AUD.
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Affiliation(s)
- Fulton T Crews
- Bowles Center for Alcohol Studies and Departments of Pharmacology and Psychiatry, School of Medicine, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Leon G Coleman
- Bowles Center for Alcohol Studies and Departments of Pharmacology and Psychiatry, School of Medicine, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Victoria A Macht
- Bowles Center for Alcohol Studies and Departments of Pharmacology and Psychiatry, School of Medicine, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Ryan P Vetreno
- Bowles Center for Alcohol Studies and Departments of Pharmacology and Psychiatry, School of Medicine, University of North Carolina School of Medicine, Chapel Hill, North Carolina
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20
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Randall CA, Sun D, Randall PA. Differential Effects of Nicotine, Alcohol, and Coexposure on Neuroimmune-Related Protein and Gene Expression in Corticolimbic Brain Regions of Rats. ACS Chem Neurosci 2023; 14:628-644. [PMID: 36705334 DOI: 10.1021/acschemneuro.2c00413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Nicotine and alcohol co-use is extremely common and their use constitutes two of the most common causes of preventable death, yet the underlying biological mechanisms are largely understudied. Activation of neuroimmune toll-like receptors (TLRs) promotes the induction of proinflammatory cascades and increases alcohol intake in rodents, which further promotes TLRs in the brain; nicotine may decrease central proinflammatory signaling. The current studies sought to determine the effects of nicotine ± alcohol (alone or in combination) on circulating blood plasma and TLR protein/gene expression in addiction-associated corticolimbic brain regions, including the prefrontal cortex-prelimbic (mPFC-PL) and nucleus accumbens core (AcbC). Adult rats were treated with alcohol (0 or 2 g/kg, IG) and exposed to nicotine vapor (0 or 30 mg/mL solution) daily for 2, 14, or 28 days. Plasma studies indicated no effects of independent exposure or coexposure in males. Coexposure decreased plasma nicotine levels versus nicotine-only treated females, yet alcohol and cotinine concentrations were unchanged. By 28 days, the anti-inflammatory cytokine IL-13 was decreased in alcohol-only females. Divergent changes in TLR3 (but not TLR4) protein occurred for independent-drug exposed males (but not coexposure), with reductions in the mPFC-PL after 14 days and increases in the AcbC by 28 days. Gene expression following chronic coexposure suggests nicotine may regionally counteract alcohol-induced inflammation, including increased AcbC-TLR3/4/7 and several downstream markers in females and increased mPFC-PL-TLR3 and -STAT3 (but not IRF3) evident in males with exposure to either drug alone. These findings give further insight into the role of sex and the neuroimmune system in independent exposure and coexposure to nicotine ± alcohol.
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Affiliation(s)
- Christie A Randall
- Department of Anesthesiology and Perioperative Medicine, College of Medicine, Pennsylvania State University, 500 University Drive, Hershey, Pennsylvania 17033, United States
| | - Dongxiao Sun
- Department of Pharmacology, College of Medicine, Pennsylvania State University, Hershey, Pennsylvania 17033 United States
| | - Patrick A Randall
- Department of Anesthesiology and Perioperative Medicine, College of Medicine, Pennsylvania State University, 500 University Drive, Hershey, Pennsylvania 17033, United States.,Department of Pharmacology, College of Medicine, Pennsylvania State University, Hershey, Pennsylvania 17033 United States
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21
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Wilson A, Periandri EM, Sievers M, Petruccelli E. Drosophila Stat92E Signaling Following Pre-exposure to Ethanol. Neurosci Insights 2023; 18:26331055221146755. [PMID: 36643884 PMCID: PMC9834942 DOI: 10.1177/26331055221146755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 12/06/2022] [Indexed: 01/11/2023] Open
Abstract
Repeated exposure to alcohol alters neuromolecular signaling that influences acute and long-lasting behaviors underlying Alcohol Use Disorder (AUD). Recent animal model research has implicated changes in the conserved JAK/STAT pathway, a signaling pathway classically associated with development and the innate immune system. How ethanol exposure impacts STAT signaling within neural cells is currently unclear. Here, we investigated the role of Drosophila Stat92E in ethanol-induced locomotion, signaling activity, and downstream transcriptional responses. Findings suggest that expressing Stat92E-RNAi causes enhanced ethanol-induced hyperactivity in flies previously exposed to ethanol. Furthermore, alternative splicing of Stat92E itself was detected after repeated ethanol exposure, although no changes were found in downstream transcriptional activity. This work adds to our growing understanding of altered neuromolecular signaling following ethanol exposure and suggests that STAT signaling may be a relevant target to consider for AUD treatment.
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Affiliation(s)
| | | | | | - Emily Petruccelli
- Emily Petruccelli, Southern Illinois University Edwardsville College of Arts and Sciences, 44 Circle Dr, Edwardsville, IL 62026, USA.
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22
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Galán-Llario M, Rodríguez-Zapata M, Gramage E, Vicente-Rodríguez M, Fontán-Baselga T, Ovejero-Benito MC, Pérez-García C, Carrasco J, Moreno-Herradón M, Sevillano J, Ramos-Álvarez MP, Zapico JM, de Pascual-Teresa B, Ramos A, Herradón G. Receptor protein tyrosine phosphatase β/ζ regulates loss of neurogenesis in the mouse hippocampus following adolescent acute ethanol exposure. Neurotoxicology 2023; 94:98-107. [PMID: 36402194 DOI: 10.1016/j.neuro.2022.11.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 11/03/2022] [Accepted: 11/14/2022] [Indexed: 11/18/2022]
Abstract
Adolescence is a critical period for brain maturation in which this organ is more vulnerable to the damaging effects of ethanol. Administration of ethanol in mice induces a rapid cerebral upregulation of pleiotrophin (PTN), a cytokine that regulates the neuroinflammatory processes induced by different insults and the behavioral effects of ethanol. PTN binds Receptor Protein Tyrosine Phosphatase (RPTP) β/ζ and inhibits its phosphatase activity, suggesting that RPTPβ/ζ may be involved in the regulation of ethanol effects. To test this hypothesis, we have treated adolescent mice with the RPTPβ/ζ inhibitor MY10 (60 mg/kg) before an acute ethanol (6 g/kg) administration. Treatment with MY10 completely prevented the ethanol-induced neurogenic loss in the hippocampus of both male and female mice. In flow cytometry studies, ethanol tended to increase the number of NeuN+/activated Caspase-3+ cells particularly in female mice, but no significant effects were found. Ethanol increased Iba1+ cell area and the total marked area in the hippocampus of female mice, suggesting sex differences in ethanol-induced microgliosis. In addition, ethanol reduced the circulating levels of IL-6 and IL-10 in both sexes, although this reduction was only found significant in males and not affected by MY10 treatment. Interestingly, MY10 alone increased the total marked area and the number of Iba1+ cells only in the female hippocampus, but tended to reduce the circulating levels of TNF-α only in male mice. In summary, the data identify a novel modulatory role of RPTPβ/ζ on ethanol-induced loss of hippocampal neurogenesis, which seems unrelated to glial and inflammatory responses. The data also suggest sex differences in RPTPβ/ζ function that may be relevant to immune responses and ethanol-induced microglial responses.
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Affiliation(s)
- Milagros Galán-Llario
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - María Rodríguez-Zapata
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - Esther Gramage
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain; Instituto de Estudios de las Adicciones, Universidad San Pablo-CEU, CEU Universities, Campus Montepríncipe, Alcorcón, 28925 Madrid, Spain
| | - Marta Vicente-Rodríguez
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain; Instituto de Estudios de las Adicciones, Universidad San Pablo-CEU, CEU Universities, Campus Montepríncipe, Alcorcón, 28925 Madrid, Spain
| | - Teresa Fontán-Baselga
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - María Carmen Ovejero-Benito
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - Carmen Pérez-García
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain; Instituto de Estudios de las Adicciones, Universidad San Pablo-CEU, CEU Universities, Campus Montepríncipe, Alcorcón, 28925 Madrid, Spain
| | - Javier Carrasco
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - Marco Moreno-Herradón
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - Julio Sevillano
- Departamento de Química y Bioquímica, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - María Pilar Ramos-Álvarez
- Departamento de Química y Bioquímica, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - José María Zapico
- Departamento de Química y Bioquímica, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - Beatriz de Pascual-Teresa
- Departamento de Química y Bioquímica, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - Ana Ramos
- Departamento de Química y Bioquímica, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain
| | - Gonzalo Herradón
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, Boadilla del Monte, 28668 Madrid, Spain; Instituto de Estudios de las Adicciones, Universidad San Pablo-CEU, CEU Universities, Campus Montepríncipe, Alcorcón, 28925 Madrid, Spain.
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23
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Grantham EK, Barchiesi R, Salem NA, Mayfield RD. Neuroimmune pathways as targets to reduce alcohol consumption. Pharmacol Biochem Behav 2023; 222:173491. [PMID: 36400266 PMCID: PMC9906983 DOI: 10.1016/j.pbb.2022.173491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 10/04/2022] [Accepted: 11/09/2022] [Indexed: 11/17/2022]
Affiliation(s)
| | - Riccardo Barchiesi
- Waggoner Center for Alcohol and Addiction Research and the Department of Neuroscience, The University of Texas at Austin, Austin, TX, 78712, United States.
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24
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Gano A, Lebonville CL, Becker HC. TLR3 activation with poly I:C exacerbates escalated alcohol consumption in dependent male C57BL/6J mice. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2022:1-12. [PMID: 36095319 DOI: 10.1080/00952990.2022.2092492] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 06/15/2022] [Accepted: 06/17/2022] [Indexed: 06/15/2023]
Abstract
Background: Activation of TLR3 receptors, which are sensitive to viral infection, has emerged as a possible mechanism that increases alcohol intake in rodents.Objectives: These studies examined whether a history of ethanol dependence exacerbated the increase in drinking driven by the TLR3 agonist poly I:C.Methods: Male C57BL/6J mice (>10 per group) were given access to ethanol (20% v/v) 2 hours a day following a history of home cage drinking or after having been rendered ethanol-dependent using a chronic intermittent ethanol (CIE) vapor model. After testing multiple doses, a 5 mg/kg repeated poly I:C challenge was used to probe the effects of repeated immune challenge, alone or in conjunction with repeated cycles of CIE, on voluntary drinking. An ethanol (12% v/v) operant self-administration model was used to test the effects of poly I:C on stress-induced reinstatement of ethanol seeking and consumption.Results: Poly I:C in naive animals resulted in transient, modest increases in ethanol intake in the home cage and in self-administration (p < 0.05). However, poly I:C challenge resulted in sensitized stress-induced ethanol consumption and evoked a strong and persistent escalation of drinking in mice with a history of dependence (p < 0.05 for both).Conclusion: Activation of viral immune defense may affect ethanol consumption in dependence and sensitivity to future stressors. As patients who suffer from alcohol use disorder are at a heightened risk for viral infection, this interaction could generate risk factors for exacerbating behaviors associated with Alcohol Use Disorders via an immune mechanism.
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Affiliation(s)
- Anny Gano
- Charleston Alcohol Research Center, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Christina L Lebonville
- Charleston Alcohol Research Center, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
| | - Howard C Becker
- Charleston Alcohol Research Center, Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
- RHJ Department of Veterans Affairs Medical Center, Charleston, SC, USA
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25
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Grodin EN, Nieto SJ, Meredith LR, Burnette E, O’Neill J, Alger J, London ED, Miotto K, Evans CJ, Irwin MR, Ray LA. Effects of ibudilast on central and peripheral markers of inflammation in alcohol use disorder: A randomized clinical trial. Addict Biol 2022; 27:e13182. [PMID: 35754106 PMCID: PMC9888600 DOI: 10.1111/adb.13182] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 04/14/2022] [Accepted: 04/27/2022] [Indexed: 02/02/2023]
Abstract
Ibudilast, a neuroimmune modulator, shows promise as a pharmacotherapy for alcohol use disorder (AUD). In vivo administration of ibudilast reduces the expression of pro-inflammatory cytokines in animal models, but its effects on markers of inflammation in humans are unknown. This preliminary study examined the effect of ibudilast on peripheral and potential central markers of inflammation in individuals with AUD. This study also explored the predictive relationship of neurometabolite markers with subsequent drinking in the trial. Non-treatment-seeking individuals with an AUD (n = 52) were randomized to receive oral ibudilast (n = 24) or placebo (n = 28) for 2 weeks. Plasma levels of peripheral inflammatory markers were measured at baseline and after 1 and 2 weeks of medication. At study mid-point, proton magnetic resonance spectroscopy was performed to measure potential neurometabolite markers of inflammation: choline-compounds (Cho), myo-inositol (MI) and creatine + phosphocreatine (Cr) in frontal and cingulate cortices from 43 participants (ibudilast: n = 20; placebo: n = 23). The treatment groups were compared on peripheral and central markers. Ibudilast-treated participants had lower Cho in superior frontal white matter and nominally lower MI in pregenual anterior cingulate cortex. Ibudilast-treated participants had nominally lower C-reactive protein levels at visit 2 and nominally lower TNF-α/IL-10 ratios, relative to placebo. C-reactive protein and Cho levels were correlated, controlling for medication. Superior frontal white matter Cho predicted drinking in the following week. Micro-longitudinal ibudilast treatment may induce peripheral and putative central anti-inflammatory responses in patients with AUD. The neurometabolite responses may be associated with reduction in drinking, suggesting an anti-inflammatory component to the therapeutic action of ibudilast.
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Affiliation(s)
- Erica N. Grodin
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
| | - Steven J. Nieto
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
| | - Lindsay R. Meredith
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
| | - Elizabeth Burnette
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA,Neuroscience Interdepartmental Program, University of California at Los Angeles, Los Angeles, CA
| | - Joseph O’Neill
- Jane & Terry Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA
| | - Jeffry Alger
- Department of Neurology, University of California Los Angeles, MC 708522, Los Angeles, CA
| | - Edythe D. London
- Brain Research Institute, University of California, Los Angeles, CA,Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA
| | - Karen Miotto
- Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA
| | - Christopher J. Evans
- Brain Research Institute, University of California, Los Angeles, CA,Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA
| | - Michael R. Irwin
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA,Jane & Terry Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA,Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA,Cousins Center for Psychoneuroimmunology, University of California at Los Angeles, Los Angeles, CA
| | - Lara A. Ray
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA,Brain Research Institute, University of California, Los Angeles, CA,Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA
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26
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Meredith LR, Grodin EN, Montoya AK, Miranda R, Squeglia LM, Towns B, Evans C, Ray LA. The effect of neuroimmune modulation on subjective response to alcohol in the natural environment. Alcohol Clin Exp Res 2022; 46:876-890. [PMID: 35362101 PMCID: PMC10460619 DOI: 10.1111/acer.14821] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/28/2022] [Accepted: 03/18/2022] [Indexed: 01/25/2023]
Abstract
BACKGROUND Despite the promising implications for novel immune therapeutics, few clinical trials have tested these therapies to date. An understanding of how immune pharmacotherapies influence complex alcohol use disorder (AUD) profiles, including subjective response to alcohol, is very limited. Initial findings show that ibudilast, a neuroimmune modulator, reduces rates of heavy drinking and measures of alcohol craving. METHODS This study is a secondary analysis of a 2-week clinical trial of ibudilast that enrolled a nontreatment-seeking sample with AUD. Eligible participants (N = 52) were randomized to receive ibudilast or matched placebo and completed daily diary assessments (DDAs) during the 2-week period. Each morning, participants reported on their mood and craving levels both before and during the previous day's drinking episode, as well as stimulation and sedation levels during the previous day's drinking episode. Multilevel models were used to compare the effects of ibudilast and placebo on subjective alcohol response. Exploratory analyses tested whether ibudilast moderated the relationship between daily stimulation/sedation and alcohol intake and whether withdrawal-related dysphoria moderated ibudilast's effects on subjective response. RESULTS Ibudilast did not significantly alter mean levels of stimulation or sedation (p's > 0.05). It did, however, moderate the effect of daily stimulation on drinking (p = 0.045). Ibudilast attenuated alcohol-induced increases in craving compared with placebo (p = 0.047), but not other subjective response measures. Ibudilast significantly tempered daily alcohol-induced changes in urge to drink and positive mood only among individuals without withdrawal-related dysphoria. CONCLUSIONS Ibudilast's effects on subjective alcohol responses appear to be nuanced and perhaps most salient for individuals drinking for positive reinforcement as distinguished from those who drink to feel normal. Consistent with previous findings, reductions in alcohol craving may represent a primary mechanism of ibudilast's effects on drinking. The ecologically valid nature of DDAs provide a clinically useful window into how individuals experience alcohol's effects while taking ibudilast.
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Affiliation(s)
| | - Erica N. Grodin
- Department of Psychology, University of California, Los Angeles, CA, USA
| | - Amanda K. Montoya
- Department of Psychology, University of California, Los Angeles, CA, USA
| | - Robert Miranda
- Center for Alcohol and Addiction Studies, Brown University, Providence, RI, USA
- E. P. Bradley Hospital, Riverside, RI, USA
| | - Lindsay M. Squeglia
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Brandon Towns
- Department of Psychology, University of California, Los Angeles, CA, USA
| | - Christopher Evans
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA, USA
| | - Lara A. Ray
- Department of Psychology, University of California, Los Angeles, CA, USA
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA, USA
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Repurposing Peroxisome Proliferator-Activated Receptor Agonists in Neurological and Psychiatric Disorders. Pharmaceuticals (Basel) 2021; 14:ph14101025. [PMID: 34681249 PMCID: PMC8538250 DOI: 10.3390/ph14101025] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/05/2021] [Accepted: 10/06/2021] [Indexed: 12/15/2022] Open
Abstract
Common pathophysiological mechanisms have emerged for different neurological and neuropsychiatric conditions. In particular, mechanisms of oxidative stress, immuno-inflammation, and altered metabolic pathways converge and cause neuronal and non-neuronal maladaptative phenomena, which underlie multifaceted brain disorders. The peroxisome proliferator-activated receptors (PPARs) are nuclear receptors modulating, among others, anti-inflammatory and neuroprotective genes in diverse tissues. Both endogenous and synthetic PPAR agonists are approved treatments for metabolic and systemic disorders, such as diabetes, fatty liver disease, and dyslipidemia(s), showing high tolerability and safety profiles. Considering that some PPAR-acting drugs permeate through the blood-brain barrier, the possibility to extend their scope from the periphery to central nervous system has gained interest in recent years. Here, we review preclinical and clinical evidence that PPARs possibly exert a neuroprotective role, thereby providing a rationale for repurposing PPAR-targeting drugs to counteract several diseases affecting the central nervous system.
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