1
|
Burnette EM, Grodin EN, Olmstead R, Ray LA, Irwin MR. Alcohol use disorder (AUD) is associated with enhanced sensitivity to cellular lipopolysaccharide challenge. Alcohol Clin Exp Res (Hoboken) 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] [What about the content of this article? (0)] [Affiliation(s)] [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.
Collapse
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
| |
Collapse
|
2
|
Meredith LR, Burnette EM, Nieto SJ, Du H, Donato S, Grodin EN, Green R, Magill M, Baskerville WA, Ray LA. Testing pharmacotherapies for alcohol use disorder with cue exposure paradigms: A systematic review and quantitative synthesis of human laboratory trial methodology. Alcohol Clin Exp Res (Hoboken) 2023; 47:1629-1645. [PMID: 37423771 DOI: 10.1111/acer.15143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/30/2023] [Accepted: 06/24/2023] [Indexed: 07/11/2023]
Abstract
Alcohol cue exposure is a widely used experimental paradigm for screening pharmacotherapies for alcohol use disorder (AUD). Medication-related reductions in cue-reactivity signal early efficacy and inform medications development. Yet, across trials, the design of cue exposure, parameter testing, and outcome reporting is heterogeneous. This systematic review is a quantitative synthesis of trial methodologies and effect size estimation for AUD medication-related craving and psychophysiological outcomes under the cue exposure paradigm. A PubMed search was conducted on January 3, 2022 based on identified pharmacotherapies for peer-reviewed articles reported in English. Study-level characteristics, including sample descriptors, paradigm design, analytic approach, and Cochrane Risk of Bias, along with descriptive statistics for cue-exposure outcomes, were coded by two independent raters. Study-level effect sizes were estimated for craving and psychophysiological outcomes separately and sample-level effect sizes were calculated for each medication. Thirty-six trials, comprising 1640 participants and testing 19 different medications satisfied eligibility criteria. All studies reported on biological sex (71% male participants on average). The exposure paradigms implemented used in vivo (n = 26), visual (n = 8), and audio script (n = 2) cues. Some trials included means for craving by medication condition in text (k = 7) or figures (k = 18). The quantitative synthesis included 63 effect sizes (craving kes = 47; psychophysiological kes = 16) from 28 unique randomized trials testing 15 medications for effects on cue reactivity. For cue-induced craving, eight medications (kes range: 1-12) demonstrated small-to-medium effects (Cohen's d range: |0.24-0.64|) compared to placebo, with individuals randomized to receive medication reporting lower craving following cue exposure. Recommendations are provided to promote further consilience, so that the utility of cue exposure paradigms can be maximized in the development of effective AUD pharmacotherapies. Future work should explore the predictive utility of medication-related reductions in cue-reactivity on clinical outcomes.
Collapse
Affiliation(s)
- Lindsay R Meredith
- Department of Psychology, University of California, Los Angeles, Los Angeles, California, USA
| | - Elizabeth M Burnette
- Brain Research Institute, University of California, Los Angeles, Los Angeles, California, USA
| | - Steven J Nieto
- Department of Psychology, University of California, Los Angeles, Los Angeles, California, USA
| | - Han Du
- Department of Psychology, University of California, Los Angeles, Los Angeles, California, USA
| | - Suzanna Donato
- Department of Psychology, University of California, Los Angeles, Los Angeles, California, USA
| | - Erica N Grodin
- Department of Psychology, University of California, Los Angeles, Los Angeles, California, USA
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, California, USA
| | - ReJoyce Green
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Molly Magill
- Center for Alcohol and Addiction Studies, Brown University School of Public Health, Providence, Rhode Island, USA
| | - Wave-Ananda Baskerville
- Department of Psychology, University of California, Los Angeles, Los Angeles, California, USA
| | - Lara A Ray
- Department of Psychology, University of California, Los Angeles, Los Angeles, California, USA
- Brain Research Institute, University of California, Los Angeles, Los Angeles, California, USA
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, California, USA
| |
Collapse
|
3
|
Grodin EN, Burnette EM, O’Neill J, Alger J, Ray LA. Alcohol Craving and Severity are Associated with Dorsal Anterior Cingulate Choline Levels in Individuals with an Alcohol Use Disorder. Alcohol Alcohol 2023; 58:289-297. [PMID: 36939375 PMCID: PMC10168708 DOI: 10.1093/alcalc/agad014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/27/2023] [Accepted: 03/01/2023] [Indexed: 03/21/2023] Open
Abstract
AIMS Magnetic resonance spectroscopy (MRS) has been used to probe inflammation in the brain. While altered MRS metabolite levels have previously been found in individuals with alcohol use disorder (AUD), the relationship between potential metabolite markers of inflammation and the clinical correlates of AUD remains understudied. Therefore, this exploratory study sought to elucidate the clinical significance of inflammation in AUD by examining relationships between metabolites, AUD severity, alcohol consumption, and craving in individuals with AUD. METHODS Data for this secondary analysis are derived from a two-week clinical trial of ibudilast to treat AUD. Forty-three non-treatment-seeking individuals with an AUD (26M/17F) completed an MRS scan and alcohol-related questionnaires. MRS was performed using a multi-voxel array placed above the corpus callosum, extending from the pregnenual anterior cingulate to premotor cortex. The dorsal anterior cingulate was selected as the volume of interest. Metabolite levels of choline-compounds (Cho), myo-inositol (mI), and creatine+phosphocreatine (Cr) were quantified. Separate hierarchical regression models were used to evaluate the independent effects of metabolite levels on alcohol craving, alcohol problem severity, and alcohol consumption. RESULTS Dorsal anterior cingulate Cho predicted alcohol craving and alcohol problem severity over and above demographics, medication, and alcohol consumption measures. mI and Cr did not predict alcohol craving or alcohol problem severity. Metabolite markers were not predictive of alcohol consumption. CONCLUSIONS This preliminary study indicates that dACC Cho is sensitive to clinical characteristics of AUD. This is a further step in advancing neurometabolites, particularly Cho, as potential biomarkers and treatment targets for AUD.
Collapse
Affiliation(s)
- Erica N Grodin
- 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
| | - Joseph O’Neill
- Jane & Terry Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA
- Brain Research Institute, University of California, Los Angeles, CA
| | - Jeffry Alger
- Department of Neurology, University of California Los Angeles, MC 708522, 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
| |
Collapse
|
4
|
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. Am J Drug 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] [What about the content of this article? (0)] [Affiliation(s)] [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.
Collapse
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
| |
Collapse
|
5
|
Nieto SJ, Grodin EN, Burnette EM, Cahill CM, Ray LA. Pain Catastrophizing Is Associated With Increased Alcohol Cue-Elicited Neural Activity Among Individuals With Alcohol Use Disorder. Alcohol Alcohol 2022; 57:727-733. [PMID: 35788255 DOI: 10.1093/alcalc/agac029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 05/31/2022] [Accepted: 06/03/2022] [Indexed: 11/13/2022] Open
Abstract
AIMS The current study examined the association between pain catastrophizing and alcohol cue-elicited brain activation in individuals with alcohol use disorder (AUD). METHODS Non-treatment seeking heavy drinkers with AUD (n = 45; 28 males) completed self-report measures of pain catastrophizing and alcohol use/problems as part of a clinical trial of the neuroimmune modulator ibudilast. Participants were randomized to either placebo (n = 25) or ibudilast (n = 20) and completed an functional magnetic resonance imaging (fMRI) scan to assess neural activation to alcohol cues 1 week into the medication trial. Multiple linear regression examined whether pain catastrophizing predicted cue-induced activation in a priori regions of interest, namely the dorsal and ventral striatum (VS). An exploratory whole-brain analysis was conducted to assess the relationship between pain catastrophizing and neural alcohol cue reactivity. RESULTS Pain catastrophizing predicted greater cue-induced activation in the dorsal (b = 0.006; P = 0.03) but not VS controlling for medication. Pain catastrophizing was positively associated with neural activation to alcohol cues in regions including the bilateral thalamus, left precuneus and left frontal pole. CONCLUSION Greater pain catastrophizing is associated with greater cue-induced neural activation in brain regions sub-serving habits and compulsive alcohol use. These findings provide initial support for a neural mechanism by which pain catastrophizing may drive alcohol craving among individuals with AUD.
Collapse
Affiliation(s)
- Steven J Nieto
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA
| | - Erica N Grodin
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA
| | - Elizabeth M Burnette
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA, USA
| | - Catherine M Cahill
- Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, Los Angeles, CA, USA.,Shirley & Stefan Hatos Center for Neuropharmacology, University of California at Los Angeles, Los Angeles, CA, USA.,Jane & Terry Semel Institute for Neuroscience and Human Behavior, University of California at Los Angeles, Los Angeles, CA, USA
| | - Lara A Ray
- 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.,Shirley & Stefan Hatos Center for Neuropharmacology, University of California at Los Angeles, Los Angeles, CA, USA.,Jane & Terry Semel Institute for Neuroscience and Human Behavior, University of California at Los Angeles, Los Angeles, CA, USA
| |
Collapse
|
6
|
Nieto SJ, Venegas A, Burnette EM, MacKillop J, Ray LA. Additive roles of tobacco and cannabis co-use in relation to delay discounting in a sample of heavy drinkers. Psychopharmacology (Berl) 2022; 239:1387-1395. [PMID: 34652499 PMCID: PMC9059652 DOI: 10.1007/s00213-021-05993-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 09/20/2021] [Indexed: 11/28/2022]
Abstract
RATIONALE Alcohol use disorder (AUD) is associated with steeper delay discounting rates; however, it is unknown whether substance co-use, particularly cannabis use, has an additive effect on discounting rates among heavy drinkers. Furthermore, it is unclear whether substance co-use and delay discounting are independently associated with AUD severity. OBJECTIVES The purpose of this study was to determine whether alcohol, tobacco, and cannabis co-use impacts delay discounting rates. We also sought to determine whether substance co-use and delay discounting were associated with AUD symptom counts. METHODS The study sample was culled from several human laboratory studies and consisted of 483 heavy drinking individuals who completed a baseline visit (prior to experimental procedures). Participants were divided into groups based on self-reported alcohol, tobacco, and cannabis use during the past 30 days: alcohol only (n = 184), alcohol + cigarettes (n = 89), alcohol + cannabis (n = 82), and tri-use (n = 128). We examined discounting rates across the 4 groups and used multiple linear regression to test whether co-use and delay discounting were associated with AUD symptoms. RESULTS After adjusting for covariates, individuals in the alcohol + cannabis group and the tri-use group had steeper discounting rates relative to the alcohol-only group. In addition, tri-use and delay discounting rates were independently correlated with a greater number of AUD symptoms. CONCLUSIONS Delay discounting rates were significantly greater among subgroups reporting cannabis use providing partial support for an additive effect, while also highlighting the importance of co-use substance type. Both tri-use and delay discounting were associated with greater AUD severity, which may provide relevant intervention targets.
Collapse
Affiliation(s)
- Steven J Nieto
- Department of Psychology, University of California Los Angeles, 1285 Franz Hall, Box 951563, Los Angeles, CA, 90095-1563, USA
| | - Alexandra Venegas
- Department of Psychology, University of California Los Angeles, 1285 Franz Hall, Box 951563, Los Angeles, CA, 90095-1563, USA
| | - Elizabeth M Burnette
- Department of Psychology, University of California Los Angeles, 1285 Franz Hall, Box 951563, Los Angeles, CA, 90095-1563, USA
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - James MacKillop
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON, Canada
| | - Lara A Ray
- Department of Psychology, University of California Los Angeles, 1285 Franz Hall, Box 951563, Los Angeles, CA, 90095-1563, USA.
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA.
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA.
| |
Collapse
|
7
|
Burnette EM, Grodin EN, Eisenberger NI, Ray LA. Endotoxin for Alcohol Research: A Call for Experimental Medicine Using Lipopolysaccharide Challenge. Alcohol Alcohol 2021; 56:715-717. [PMID: 33592623 DOI: 10.1093/alcalc/agaa148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/16/2020] [Accepted: 12/23/2020] [Indexed: 11/13/2022] Open
Abstract
Studies of inflammation in alcohol use disorder (AUD) are overwhelmingly preclinical, and translation to clinical samples is necessary. Endotoxin administration has been used successfully in humans to study mood disorders, offering a translational, reliable and safe model that may be validated in AUD research. We argue for the use of endotoxin challenge to elucidate the interplay between AUD and inflammation.
Collapse
Affiliation(s)
- Elizabeth M Burnette
- Department of Psychology, University of California at Los Angeles, 5555 Campus Hall, Los Angeles, CA 90095, USA.,Neuroscience Interdepartmental Program, University of California at Los Angeles, 5555 Campus Hall, Los Angeles, CA 90095, USA
| | - Erica N Grodin
- Department of Psychology, University of California at Los Angeles, 5555 Campus Hall, Los Angeles, CA 90095, USA
| | - Naomi I Eisenberger
- Department of Psychology, University of California at Los Angeles, 5555 Campus Hall, Los Angeles, CA 90095, USA
| | - Lara A Ray
- Department of Psychology, University of California at Los Angeles, 5555 Campus Hall, Los Angeles, CA 90095, USA.,Department of Psychiatry and Biobehavioral Sciences, University of California at Los Angeles, 5555 Campus Hall, Los Angeles, CA 90095, USA.,Brain Research Institute, University of California at Los Angeles, 5555 Campus Hall, Los Angeles, CA 90095, USA
| |
Collapse
|
8
|
Meredith LR, Burnette EM, Grodin EN, Irwin MR, Ray LA. Immune treatments for alcohol use disorder: A translational framework. Brain Behav Immun 2021; 97:349-364. [PMID: 34343618 PMCID: PMC9044974 DOI: 10.1016/j.bbi.2021.07.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 07/10/2021] [Accepted: 07/28/2021] [Indexed: 12/14/2022] Open
Abstract
While the immune system is essential for survival, an excessive or prolonged inflammatory response, such as that resulting from sustained heavy alcohol use, can damage the host and contribute to psychiatric disorders. A growing body of literature indicates that the immune system plays a critical role in the development and maintenance of alcohol use disorder (AUD). As such, there is enthusiasm for treatments that can restore healthy levels of inflammation as a mechanism to reduce drinking and promote recovery. In this qualitative literature review, we provide a conceptual rationale for immune therapies and discuss progress in medications development for AUD focused on the immune system as a treatment target. This review is organized into sections based on primary signaling pathways targeted by the candidate therapies, namely: (a) toll-like receptors, (b) phosphodiesterase inhibitors, (c) peroxisome proliferator-activated receptors, (d) microglia and astrocytes, (e) other immune pharmacotherapies, and (f) behavioral therapies. As relevant within each section, we examine the basic biological mechanisms of each class of therapy and evaluate preclinical research testing the role of the therapy on mitigating alcohol-related behaviors in animal models. To the extent available, translational findings are reviewed with discussion of completed and ongoing randomized clinical trials and their findings to date. An applied and clinically focused approach is taken to identify the potential clinical applications of the various treatments reviewed. We conclude by delineating the most promising candidate treatments and discussing future directions by considering opportunities for immune treatment development and personalized medicine for AUD.
Collapse
Affiliation(s)
- Lindsay R Meredith
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Elizabeth M Burnette
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Erica N Grodin
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Michael R Irwin
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA; Jane and Terry Semel Institute for Neuroscience and Human Behavior, University of California at Los Angeles, Los Angeles, CA, USA; Cousins Center for Psychoneuroimmunology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Lara A Ray
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA.
| |
Collapse
|
9
|
Burnette EM, Ray LA, Irwin MR, Grodin EN. Ibudilast attenuates alcohol cue-elicited frontostriatal functional connectivity in alcohol use disorder. Alcohol Clin Exp Res 2021; 45:2017-2028. [PMID: 34585396 PMCID: PMC8602728 DOI: 10.1111/acer.14696] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 08/09/2021] [Accepted: 08/12/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND Ibudilast, a novel neuroimmune modulator being studied to treat alcohol use disorder (AUD), was shown in a randomized controlled trial (NCT03489850) to reduce ventral striatum (VS) activation in response to visual alcohol cues. The present study extended this finding by probing the effects of ibudilast on alcohol cue-elicited functional connectivity (i.e., temporally correlated activation) with the VS seed. The study also tests the association between functional connectivity and alcohol use during the trial. METHODS Non-treatment-seeking participants (n = 45) with current alcohol use disorder were randomized to receive twice-daily dosing with either ibudilast (50 mg; n = 20) or placebo (n = 25). Upon reaching the target dosagee of the medication or placebo, participants completed a functional neuroimaging alcohol cue reactivity paradigm. Drinks per drinking day were assessed at baseline and daily during the 2-week trial. RESULTS Ibudilast reduced alcohol cue-elicited functional connectivity between the VS seed and reward-processing regions including the orbitofrontal and anterior cingulate cortices compared with placebo (p < 0.05). Cue-elicited functional connectivity was correlated with drinks per drinking day (R2 = 0.5351, p < 0.001), and ibudilast reduced this association in similar reward-processing regions compared with placebo. CONCLUSIONS Ibudilast's effects on drinking outcomes may be related to the attenuation of functional connectivity in frontostriatal circuits related to reward processing. These results provide an important proof of concept for this novel pharmacotherapy and support the clinical utility of incorporating neuroimaging-and especially functional connectivity-analyses into medication development.
Collapse
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
| | - 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
| | - 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 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
| | - Erica N. Grodin
- Department of Psychology, University of California at Los Angeles, Los Angeles, CA
| |
Collapse
|
10
|
Grodin EN, Burnette EM, Green R, Lim AC, Miotto K, Ray LA. Combined varenicline and naltrexone attenuates alcohol cue-elicited activation in heavy drinking smokers. Drug Alcohol Depend 2021; 225:108825. [PMID: 34175784 PMCID: PMC9059649 DOI: 10.1016/j.drugalcdep.2021.108825] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND There is a strong bidirectional relationship between the use of alcohol and cigarettes which results in various challenges for treating those who co-use both substances. While varenicline and naltrexone each have FDA-approval for nicotine and alcohol use disorder, respectively, there is evidence that their clinical benefit may extend across the two disorders. Critically, the effect of combined varenicline and naltrexone on neural reactivity to alcohol cues among heavy drinking smokers has not yet been studied. Probing the effect of the combination therapy on alcohol cue-reactivity may give insight to the mechanisms underlying its efficacy. METHODS Forty-seven heavy drinking smokers enrolled in two medication studies were randomized to receive varenicline alone (n = 11), varenicline plus naltrexone (n = 11), or placebo (n = 25). Participants completed an fMRI alcohol cue-reactivity task and rated their in-scanner alcohol craving. Whole-brain analyses examined the effect of medication on alcohol cue-elicited neural response. RESULTS Varenicline plus naltrexone attenuated alcohol cue-elicited activation in mesolimbic regions relative to varenicline alone and to placebo (Z > 2.3, p < 0.05). The combination varenicline and naltrexone group also endorsed lower in-scanner alcohol craving relative to varenicline alone group (p = 0.04). CONCLUSIONS These findings provide evidence for the benefit of combined therapy of varenicline and naltrexone over varenicline alone for the attenuation of alcohol cue-elicited neural activation. This study provides a preliminary proof-of-mechanism for this combination pharmacotherapy and suggests that naltrexone may be driving the reductions in cue-elicited alcohol craving in the brain. Further clinical studies using the combined therapy to treat heavy drinking smokers are warranted.
Collapse
Affiliation(s)
- Erica N. Grodin
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Elizabeth M. Burnette
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA 90095, United States,Neuroscience Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - ReJoyce Green
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Aaron C. Lim
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Karen Miotto
- Neuroscience Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Lara A. Ray
- Department of Psychology, University of California, Los Angeles, Los Angeles, CA 90095, United States,Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA 90095, United States,Brain Research Institute, University of California, Los Angeles, Los Angeles, CA 90095, United States,Corresponding author at: University of California, Los Angeles, Psychology Department, 1285 Franz Hall, Box 951563, Los Angeles, CA 90095-1563, United States. (L.A. Ray)
| |
Collapse
|
11
|
Burnette EM, Grodin EN, Ghahremani DG, Galván A, Kohno M, Ray LA, London ED. Diminished cortical response to risk and loss during risky decision making in alcohol use disorder. Drug Alcohol Depend 2021; 218:108391. [PMID: 33153830 PMCID: PMC7750289 DOI: 10.1016/j.drugalcdep.2020.108391] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/23/2020] [Accepted: 10/26/2020] [Indexed: 10/23/2022]
Abstract
BACKGROUND Risky decision-making is an important facet of addiction. Individuals with alcohol dependence show abnormalities in gambling and other risk-taking tasks. In one such measure, the Balloon Analogue Risk Task (BART), participants sequentially choose to pump a virtual balloon to increase potential reward while the risk of explosion increases, or to cash-out and take earnings. In a prior study, alcohol-dependent participants differed from controls in brain activation during decision-making on the BART, but the relationship between risk/reward magnitude and brain activation was not studied, nor were participants compared to controls. Here we compared the degree to which risk and magnitude of reward influenced brain activation in alcohol-dependent participants vs. controls during decision-making on the BART. METHODS Thirty-two participants (16 alcohol-dependent, 16 control; 5 females/group) performed the BART during fMRI. A parametric analysis tested for a relationship between risk/reward magnitude and activation in rDLPFC and bilateral striatum regions of interest when participants chose to take risk or to cash out. An exploratory whole-brain voxel-wise analysis of mean activation during pumping, cash-out, and explosion events was also conducted. RESULTS Compared with controls, alcohol-dependent participants displayed less modulation of activation in the rDLPFC when taking risk. Exploratory analyses found that alcohol-dependent participants showed less activation than controls during explosions in a cluster including the insula. No differences were seen in striatal activation. CONCLUSIONS Insensitivity of the rDLPFC to risk and of the insula to loss may contribute to decision-making deficits in alcohol dependence.
Collapse
Affiliation(s)
- Elizabeth M. Burnette
- Department of Psychology, University of California, Los Angeles, CA,Neuroscience Interdepartmental Program, University of California, Los Angeles, CA
| | - Erica N. Grodin
- Department of Psychology, University of California, Los Angeles, CA,Department of Psychiatry and Biobehavioral Sciences, UCLA School of Medicine, Los Angeles, CA
| | - Dara G. Ghahremani
- Department of Psychiatry and Biobehavioral Sciences, UCLA School of Medicine, Los Angeles, CA
| | - Adriana Galván
- Department of Psychology, University of California, Los Angeles, CA,Neuroscience Interdepartmental Program, University of California, Los Angeles, CA,Brain Research Institute, University of California, Los Angeles, CA
| | - Milky Kohno
- Department of Psychiatry, Oregon Health and Sciences University, Portland, OR
| | - Lara A. Ray
- Department of Psychology, University of California, Los Angeles, CA,Neuroscience Interdepartmental Program, University of California, Los Angeles, CA,Department of Psychiatry and Biobehavioral Sciences, UCLA School of Medicine, Los Angeles, CA,Brain Research Institute, University of California, Los Angeles, CA
| | - Edythe D. London
- Neuroscience Interdepartmental Program, University of California, Los Angeles, CA,Department of Psychiatry and Biobehavioral Sciences, UCLA School of Medicine, Los Angeles, CA,Brain Research Institute, University of California, Los Angeles, CA,Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA
| |
Collapse
|
12
|
Burnette EM, Grodin EN, Schacht JP, Ray LA. Clinical and Neural Correlates of Reward and Relief Drinking. Alcohol Clin Exp Res 2020; 45:194-203. [PMID: 33119924 DOI: 10.1111/acer.14495] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 10/19/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Alcohol use disorder (AUD) is heterogenous. One approach to parsing this heterogeneity is to phenotype individuals by their underlying motivation to drink, specifically drinking for reward (i.e., positive reinforcement) or for relief (i.e., negative reinforcement/normalizing). Reward- versus relief-motivated behavior is thought to be associated with a shift from ventral to dorsal striatal (DS) signaling. The present study examined whether reward and relief drinking were differentially associated with other clinical characteristics and with alcohol cue-elicited activation of the ventral and dorsal striatum. METHODS Non-treatment-seeking heavy drinkers (N = 184; 61 female, 123 male) completed the UCLA Reward, Relief, Habit Drinking Scale (RRHDS) and the Reasons for Heavy Drinking Questionnaire (RHDQ), to categorize drinking motivation. Measures of alcohol use, alcohol problems, mood, and craving were also collected. A subset of participants (N = 45; 17 female, 28 male) also completed a functional neuroimaging alcohol cue reactivity task. RESULTS RRHDS-designated relief/habit drinkers scored lower than reward drinkers on the RHDQ Reinforcement subscale (p = 0.04) and higher on the RHDQ Normalizing subscale (p = 0.004). Relief/habit drinkers also demonstrated greater AUD severity on a host of clinical measures. Relief/habit drinkers displayed higher cue-elicited DS activation compared with reward drinkers (p = 0.04), while ventral striatal cue-elicited activation did not significantly differ between groups. CONCLUSIONS Our findings support and extend the differentiation of reward from relief/habit-motivated drinking and suggest that differences in DS response to conditioned alcohol cues may underlie this distinction. Elucidating neurobiological and clinical differences between these subtypes may facilitate treatment matching and precision medicine for AUD.
Collapse
Affiliation(s)
- Elizabeth M Burnette
- From the, Department of Psychology, (EMB, ENG, LAR), University of California at Los Angeles, Los Angeles, California.,Neuroscience Interdepartmental Program, (EMB), University of California at Los Angeles, Los Angeles, California
| | - Erica N Grodin
- From the, Department of Psychology, (EMB, ENG, LAR), University of California at Los Angeles, Los Angeles, California
| | - Joseph P Schacht
- Department of Psychiatry, (JPS), University of Colorado - Anschutz Medical Campus, Denver, Colorado
| | - Lara A Ray
- From the, Department of Psychology, (EMB, ENG, LAR), University of California at Los Angeles, Los Angeles, California.,Department of Psychiatry and Biobehavioral Sciences, (LAR), University of California at Los Angeles, Los Angeles, California
| |
Collapse
|
13
|
Burnette EM, Baskerville WA, Grodin EN, Ray LA. Ibudilast for alcohol use disorder: study protocol for a phase II randomized clinical trial. Trials 2020; 21:779. [PMID: 32912290 PMCID: PMC7488583 DOI: 10.1186/s13063-020-04670-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/11/2020] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Alcohol use disorder (AUD) is a chronic and relapsing condition for which current pharmacological treatments are only modestly effective. The development of efficacious medications for AUD remains a high research priority with recent emphasis on identifying novel molecular targets for AUD treatment and to efficiently screen new compounds aimed at those targets. Ibudilast, a phosphodiesterase inhibitor, has been advanced as a novel addiction pharmacotherapy that targets neurotrophin signaling and neuroimmune function. METHODS This study will conduct a 12-week, double-blind, placebo controlled randomized clinical trial of ibudilast (50 mg BID) for AUD treatment. We will randomize 132 treatment-seeking men and women with current AUD. We will collect a number of alcohol consumption outcomes. Primary among these is percent heavy drinking days (PHDD); secondary drinking outcomes include drinks per day, drinks per drinking day, percent days abstinent, percent subjects with no heavy drinking days, and percent subjects abstinent, as well as measures of alcohol craving and negative mood. Additionally, participants will have the option to opt-in to a neuroimaging session in which we examine the effects of ibudilast on neural activation to psychosocial stress and alcohol cues. Finally, we will also collect plasma levels of proinflammatory markers, as well as subjective and biological (salivary cortisol) markers of stress response. DISCUSSION This study will further develop ibudilast, a safe and promising novel compound with strong preclinical and clinical safety data for AUD, and will probe biological mechanisms underlying the effects of Ibudilast on stress, neuroinflammation, and alcohol cue-reactivity and craving. If ibudilast proves superior to placebo in this study, it will set the stage for a confirmatory multi-site trial leading to FDA approval of a novel AUD treatment. TRIAL REGISTRATION ClinicalTrials.gov NCT03594435 "Ibudilast for the Treatment of Alcohol Use Disorder". Registered on 20 July 2018.
Collapse
Affiliation(s)
- Elizabeth M Burnette
- Department of Psychology, University of California Los Angeles, Los Angeles, CA, USA. .,Interdepartmental Program for Neuroscience, University of California Los Angeles, Los Angeles, CA, USA.
| | | | - Erica N Grodin
- Department of Psychology, University of California Los Angeles, Los Angeles, CA, USA
| | - Lara A Ray
- Department of Psychology, University of California Los Angeles, Los Angeles, CA, USA.,Interdepartmental Program for Neuroscience, University of California Los Angeles, Los Angeles, CA, USA.,Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA, USA
| |
Collapse
|
14
|
Burnette EM, Grodin EN, Lim AC, MacKillop J, Karno MP, Ray LA. Association between impulsivity and neural activation to alcohol cues in heavy drinkers. Psychiatry Res Neuroimaging 2019; 293:110986. [PMID: 31622796 PMCID: PMC7238761 DOI: 10.1016/j.pscychresns.2019.110986] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 09/16/2019] [Accepted: 09/23/2019] [Indexed: 12/20/2022]
Abstract
This study examines associations between two measures of impulsivity and brain response to alcohol taste cues. Impulsivity is both a risk factor for and a consequence of alcohol use and misuse. Frontostriatal circuits are linked to both impulsivity and addiction-related behaviors, including response to alcohol cues. Non-treatment-seeking heavy drinkers (n = 55) completed (i) an fMRI alcohol taste cue-reactivity paradigm; (ii) the monetary choice questionnaire (MCQ), a measure of choice impulsivity where participants choose between smaller, sooner rewards and larger, delayed rewards; (iii) and the UPPS-P Impulsive Behavior Scale, a self-report measure assessing five impulsivity factors. General linear models identified associations between neural alcohol taste cue-reactivity and impulsivity, adjusting for age, gender, and smoking status. Self-reported sensation seeking was positively associated with alcohol taste cue-elicited activation in frontostriatal regions, such that individuals who reported higher sensation seeking displayed greater neural response to alcohol taste cues. Conversely, delay discounting was negatively associated with activation in frontoparietal regions, such that individuals who reported greater discounting showed less cue-elicited activation. There were no significant associations between other self-reported impulsivity subscales and alcohol taste cue-reactivity. These results indicate that sensation seeking is associated with reward responsivity, while delay discounting is associated with recruitment of self-control circuitry.
Collapse
Affiliation(s)
- Elizabeth M Burnette
- Interdepartmental Program for Neuroscience, University of California, Los Angeles, CA, USA
| | - Erica N Grodin
- Department of Psychology, University of California, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, UCLA School of Medicine, University of California, Los Angeles, CA, USA
| | - Aaron C Lim
- Department of Psychology, University of California, Los Angeles, CA, USA
| | - James MacKillop
- Department of Psychiatry and Behavioral Neurosciences, McMaster University, Hamilton, ON, Canada
| | - Mitchell P Karno
- Department of Psychiatry and Biobehavioral Sciences, UCLA School of Medicine, University of California, Los Angeles, CA, USA
| | - Lara A Ray
- Interdepartmental Program for Neuroscience, University of California, Los Angeles, CA, USA; Department of Psychology, University of California, Los Angeles, CA, USA; Department of Psychiatry and Biobehavioral Sciences, UCLA School of Medicine, University of California, Los Angeles, CA, USA.
| |
Collapse
|