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Walker KA, Rhodes ST, Liberman DA, Gore AC, Bell MR. Microglial responses to inflammatory challenge in adult rats altered by developmental exposure to polychlorinated biphenyls in a sex-specific manner. Neurotoxicology 2024; 104:95-115. [PMID: 39038526 DOI: 10.1016/j.neuro.2024.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 07/11/2024] [Accepted: 07/17/2024] [Indexed: 07/24/2024]
Abstract
Polychlorinated biphenyls are ubiquitous environmental contaminants linkedc with peripheral immune and neural dysfunction. Neuroimmune signaling is critical to brain development and later health; however, effects of PCBs on neuroimmune processes are largely undescribed. This study extends our previous work in neonatal or adolescent rats by investigating longer-term effects of perinatal PCB exposure on later neuroimmune responses to an inflammatory challenge in adulthood. Male and female Sprague-Dawley rats were exposed to a low-dose, environmentally relevant, mixture of PCBs (Aroclors 1242, 1248, and 1254, 1:1:1, 20 μg / kg dam BW per gestational day) or oil control during gestation and via lactation. Upon reaching adulthood, rats were given a mild inflammatory challenge with lipopolysaccharide (LPS, 50 μg / kg BW, ip) or saline control and then euthanized 3 hours later for gene expression analysis or 24 hours later for immunohistochemical labeling of Iba1+ microglia. PCB exposure did not alter gene expression or microglial morphology independently, but instead interacted with the LPS challenge in brain region- and sex-specific ways. In the female hypothalamus, PCB exposure blunted LPS responses of neuroimmune and neuromodulatory genes without changing microglial morphology. In the female prefrontal cortex, PCBs shifted Iba1+ cells from reactive to hyperramified morphology in response to LPS. Conversely, in the male hypothalamus, PCBs shifted cell phenotypes from hyperramified to reactive morphologies in response to LPS. The results highlight the potential for long-lasting effects of environmental contaminants that are differentially revealed over a lifetime, sometimes only after a secondary challenge. These neuroimmune endpoints are possible mechanisms for PCB effects on a range of neural dysfunction in adulthood, including mental health and neurodegenerative disorders. The findings suggest possible interactions with other environmental challenges that also influence neuroimmune systems.
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Affiliation(s)
- Katherine A Walker
- Departments of Biological Sciences and Health Sciences, DePaul University, Chicago, IL 60614, USA.
| | - Simone T Rhodes
- Departments of Biological Sciences and Health Sciences, DePaul University, Chicago, IL 60614, USA.
| | - Deborah A Liberman
- Departments of Biological Sciences and Health Sciences, DePaul University, Chicago, IL 60614, USA.
| | - Andrea C Gore
- Division of Pharmacology and Toxicology, College of Pharmacy and Department of Psychology, University of Texas at Austin, Austin, TX 78712, USA.
| | - Margaret R Bell
- Departments of Biological Sciences and Health Sciences, DePaul University, Chicago, IL 60614, USA; Division of Pharmacology and Toxicology, College of Pharmacy and Department of Psychology, University of Texas at Austin, Austin, TX 78712, USA.
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Chéry SL, O'Buckley TK, Boero G, Balan I, Morrow AL. Neurosteroid [3α,5α]3-hydroxypregnan-20-one inhibition of chemokine monocyte chemoattractant protein-1 in alcohol-preferring rat brain neurons, microglia, and astroglia. ALCOHOL, CLINICAL & EXPERIMENTAL RESEARCH 2024. [PMID: 38991981 DOI: 10.1111/acer.15404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 06/21/2024] [Accepted: 06/26/2024] [Indexed: 07/13/2024]
Abstract
BACKGROUND Neuroimmune dysfunction in alcohol use disorder (AUD) is associated with activation of myeloid differentiation primary response 88 (MyD88)-dependent Toll-like receptors (TLR) resulting in overexpression of the chemokine monocyte chemoattractant protein-1 (MCP-1/CCL2). MCP-1 overexpression in the brain is linked to anxiety, higher alcohol intake, neuronal death, and activation of microglia observed in AUD. The neurosteroid [3α,5α][3-hydroxypregnan-20-one (3α,5α-THP) has been reported as an inhibitor of MyD88-dependent TLR activation and MCP-1 overexpression in mouse and human macrophages and the brain of alcohol-preferring (P) rats. METHODS We investigated how 3α,5α-THP regulates MCP-1 expression at the cellular level in P rat nucleus accumbens (NAc) and central amygdala (CeA). We focused on neurons, microglia, and astrocytes, examining the individual voxel density of MCP-1, neuronal marker NeuN, microglial marker IBA1, astrocytic marker GFAP, and their shared voxel density, defined as intersection. Ethanol-naïve male and female P rats were perfused 1 h after IP injections of 15 mg/kg of 3α,5α-THP, or vehicle. The NAc and CeA were imaged using confocal microscopy following double-immunofluorescence staining for MCP-1 with NeuN, IBA1, and GFAP, respectively. RESULTS MCP-1 intersected with NeuN predominantly and IBA1/GFAP negligibly. 3α,5α-THP reduced MCP-1 expression in NeuN-labeled cells by 38.27 ± 28.09% in male and 56.11 ± 21.46% in female NAc, also 37.99 ± 19.53% in male and 54.96 ± 30.58% in female CeA. In females, 3α,5α-THP reduced the MCP-1 within IBA1 and GFAP-labeled voxels in the NAc and CeA. Conversely, in males, 3α,5α-THP did not significantly alter the MCP-1 within IBA1 in NAc or with GFAP in the CeA. Furthermore, 3α,5α-THP decreased levels of IBA1 in both regions and sexes with no impact on GFAP or NeuN levels. Secondary analysis performed on data normalized to % control values indicated that no significant sex differences were present. CONCLUSIONS These data suggest that 3α,5α-THP inhibits neuronal MCP-1 expression and decreases the proliferation of microglia in P rats. These results increase our understanding of potential mechanisms for 3α,5α-THP modulation of ethanol consumption.
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Affiliation(s)
- Samantha Lucenell Chéry
- Bowles Center for Alcohol Studies, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Neuroscience Curriculum, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Todd K O'Buckley
- Bowles Center for Alcohol Studies, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Giorgia Boero
- Bowles Center for Alcohol Studies, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Psychiatry, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Pharmacology, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Irina Balan
- Bowles Center for Alcohol Studies, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Psychiatry, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - A Leslie Morrow
- Bowles Center for Alcohol Studies, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Psychiatry, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Pharmacology, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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Balan I, Boero G, Chéry SL, McFarland MH, Lopez AG, Morrow AL. Neuroactive Steroids, Toll-like Receptors, and Neuroimmune Regulation: Insights into Their Impact on Neuropsychiatric Disorders. Life (Basel) 2024; 14:582. [PMID: 38792602 PMCID: PMC11122352 DOI: 10.3390/life14050582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/18/2024] [Accepted: 04/28/2024] [Indexed: 05/26/2024] Open
Abstract
Pregnane neuroactive steroids, notably allopregnanolone and pregnenolone, exhibit efficacy in mitigating inflammatory signals triggered by toll-like receptor (TLR) activation, thus attenuating the production of inflammatory factors. Clinical studies highlight their therapeutic potential, particularly in conditions like postpartum depression (PPD), where the FDA-approved compound brexanolone, an intravenous formulation of allopregnanolone, effectively suppresses TLR-mediated inflammatory pathways, predicting symptom improvement. Additionally, pregnane neurosteroids exhibit trophic and anti-inflammatory properties, stimulating the production of vital trophic proteins and anti-inflammatory factors. Androstane neuroactive steroids, including estrogens and androgens, along with dehydroepiandrosterone (DHEA), display diverse effects on TLR expression and activation. Notably, androstenediol (ADIOL), an androstane neurosteroid, emerges as a potent anti-inflammatory agent, promising for therapeutic interventions. The dysregulation of immune responses via TLR signaling alongside reduced levels of endogenous neurosteroids significantly contributes to symptom severity across various neuropsychiatric disorders. Neuroactive steroids, such as allopregnanolone, demonstrate efficacy in alleviating symptoms of various neuropsychiatric disorders and modulating neuroimmune responses, offering potential intervention avenues. This review emphasizes the significant therapeutic potential of neuroactive steroids in modulating TLR signaling pathways, particularly in addressing inflammatory processes associated with neuropsychiatric disorders. It advances our understanding of the complex interplay between neuroactive steroids and immune responses, paving the way for personalized treatment strategies tailored to individual needs and providing insights for future research aimed at unraveling the intricacies of neuropsychiatric disorders.
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Affiliation(s)
- Irina Balan
- Bowles Center for Alcohol Studies, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (I.B.); (S.L.C.); (M.H.M.); (A.G.L.)
- Department of Psychiatry, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Giorgia Boero
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710, USA;
| | - Samantha Lucenell Chéry
- Bowles Center for Alcohol Studies, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (I.B.); (S.L.C.); (M.H.M.); (A.G.L.)
- Neuroscience Curriculum, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Minna H. McFarland
- Bowles Center for Alcohol Studies, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (I.B.); (S.L.C.); (M.H.M.); (A.G.L.)
- Neuroscience Curriculum, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Alejandro G. Lopez
- Bowles Center for Alcohol Studies, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (I.B.); (S.L.C.); (M.H.M.); (A.G.L.)
- Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - A. Leslie Morrow
- Bowles Center for Alcohol Studies, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (I.B.); (S.L.C.); (M.H.M.); (A.G.L.)
- Department of Psychiatry, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Pharmacology, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, 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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Balan I, Grusca A, O’Buckley TK, Morrow AL. Neurosteroid [3α,5α]-3-hydroxy-pregnan-20-one enhances IL-10 production via endosomal TRIF-dependent TLR4 signaling pathway. Front Endocrinol (Lausanne) 2023; 14:1299420. [PMID: 38179300 PMCID: PMC10765172 DOI: 10.3389/fendo.2023.1299420] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 11/24/2023] [Indexed: 01/06/2024] Open
Abstract
Background Previous studies demonstrated the inhibitory effect of allopregnanolone (3α,5α-THP) on the activation of inflammatory toll-like receptor 4 (TLR4) signals in RAW264.7 macrophages and the brains of selectively bred alcohol-preferring (P) rats. In the current study, we investigated the impact of 3α,5α-THP on the levels of IL-10 and activation of the TRIF-dependent endosomal TLR4 pathway. Methods The amygdala and nucleus accumbens (NAc) of P rats, which exhibit innately activated TLR4 pathways as well as RAW264.7 cells, were used. Enzyme-linked immunosorbent assays (ELISA) and immunoblotting assays were used to ascertain the effects of 3α,5α-THP on the TRIF-dependent endosomal TLR4 pathway and endosomes were isolated to examine translocation of TLR4 and TRIF. Additionally, we investigated the effects of 3α,5α-THP and 3α,5α-THDOC (0.1, 0.3, and 1.0 µM) on the levels of IL-10 in RAW264.7 macrophages. Finally, we examined whether inhibiting TRIF (using TRIF siRNA) in RAW264.7 cells altered the levels of IL-10. Results 3α,5α-THP administration facilitated activation of the endosomal TRIF-dependent TLR4 pathway in males, but not female P rats. 3α,5α-THP increased IL-10 levels (+13.2 ± 6.5%) and BDNF levels (+21.1 ± 11.5%) in the male amygdala. These effects were associated with increases in pTRAM (+86.4 ± 28.4%), SP1 (+122.2 ± 74.9%), and PI(3)K-p110δ (+61.6 ± 21.6%), and a reduction of TIRAP (-13.7 ± 6.0%), indicating the activation of the endosomal TRIF-dependent TLR4 signaling pathway. Comparable effects were observed in NAc of these animals. Furthermore, 3α,5α-THP enhanced the accumulation of TLR4 (+43.9 ± 11.3%) and TRIF (+64.8 ± 32.8%) in endosomes, with no significant effect on TLR3 accumulation. Additionally, 3α,5α-THP facilitated the transition from early endosomes to late endosomes (increasing Rab7 levels: +35.8 ± 18.4%). In RAW264.7 cells, imiquimod (30 µg/mL) reduced IL-10 while 3α,5α-THP and 3α,5α-THDOC (0.1, 0.3, and 1.0 µM) restored IL-10 levels. To determine the role of the TRIF-dependent TLR4 signaling pathway in IL-10 production, the downregulation of TRIF (-62.9 ± 28.2%) in RAW264.7 cells led to a reduction in IL-10 levels (-42.3 ± 8.4%). TRIF (-62.9 ± 28.2%) in RAW264.7 cells led to a reduction in IL-10 levels (-42.3 ± 8.4%) and 3α,5α-THP (1.0 µM) no longer restored the reduced IL-10 levels. Conclusion The results demonstrate 3α,5α-THP enhancement of the endosomal TLR4-TRIF anti-inflammatory signals and elevations of IL-10 in male P rat brain that were not detected in female P rat brain. These effects hold significant implications for controlling inflammatory responses in both the brain and peripheral immune cells.
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Affiliation(s)
- Irina Balan
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Adelina Grusca
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Todd K. O’Buckley
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - A. Leslie Morrow
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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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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Airapetov MI, Eresko SO, Skabelkin DA, Iskalieva AR, Lebedev AA, Bychkov ER, Shabanov PD. [The effect of rifampicin on the system of Toll-like receptors in the nucleus accumbens of the brain of long-term alcoholized rats during alcohol withdrawal]. BIOMEDITSINSKAIA KHIMIIA 2022; 68:279-287. [PMID: 36005846 DOI: 10.18097/pbmc20226804279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Nucleus accumbens (NAc) is the ventral part of the striatum of the brain; it is an important part of the mesolimbic pathway involved in the reward system that mediates the formation of various forms of addiction, in particular alcohol addiction. Neuroimaging data and in vitro studies indicate the development of a pronounced neurodegenerative process in the NAc, with long-term alcohol use, but the key mechanisms mediating this process remain unknown. In recent years, the attention of researchers has been focused on studying the system of Toll-like receptors (TLRs), the increased activity of which is clearly shown in the cerebral cortex and hippocampus during prolonged alcohol exposure, but there is a need to study the role of this system in other brain structures. In this study, we have shown that prolonged alcohol exposure (2 months) with moderate doses of ethanol (2 g/kg) promotes a pronounced increase in the expression of the Tlr4 gene and its endogenous ligand Hmgb1 in NAc during the period of alcohol withdrawal in rats. Injections of rifampicin (100 mg/kg) reduced the elevated expression level of Hmgb1, Tlr4, as well as pro-inflammatory cytokine genes (IL1β, IL6), while the administration of the drug increased the reduced level of mRNA of anti-inflammatory cytokines (IL10, IL11).
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Affiliation(s)
- M I Airapetov
- Department of Neuropharmacology, Institute of Experimental Medicine, St. Petersburg, Russia; Department of Pharmacology, St. Petersburg State Pediatric Medical University
| | - S O Eresko
- Department of Neuropharmacology, Institute of Experimental Medicine, St. Petersburg, Russia; Research and Training Center of Molecular and Cellular Technologies, St. Petersburg, Russia
| | - D A Skabelkin
- Department of Neuropharmacology, Institute of Experimental Medicine, St. Petersburg, Russia
| | - A R Iskalieva
- Department of Neuropharmacology, Institute of Experimental Medicine, St. Petersburg, Russia
| | - A A Lebedev
- Department of Neuropharmacology, Institute of Experimental Medicine, St. Petersburg, Russia
| | - E R Bychkov
- Department of Neuropharmacology, Institute of Experimental Medicine, St. Petersburg, Russia
| | - P D Shabanov
- Department of Neuropharmacology, Institute of Experimental Medicine, St. Petersburg, Russia; Department of Pharmacology, Kirov Military Medical Academy, St. Petersburg, Russia
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Balan I, Aurelian L, Williams KS, Campbell B, Meeker RB, Morrow AL. Inhibition of human macrophage activation via pregnane neurosteroid interactions with toll-like receptors: Sex differences and structural requirements. Front Immunol 2022; 13:940095. [PMID: 35967446 PMCID: PMC9373802 DOI: 10.3389/fimmu.2022.940095] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/07/2022] [Indexed: 11/13/2022] Open
Abstract
We recently discovered that (3α,5α)3-hydroxypregnan-20-one (allopregnanolone) inhibits pro-inflammatory toll-like receptor (TLR) activation and cytokine/chemokine production in mouse macrophage RAW264.7 cells. The present studies evaluate neurosteroid actions upon TLR activation in human macrophages from male and female healthy donors. Buffy coat leukocytes were obtained from donors at the New York Blood Center (http://nybloodcenter.org/), and peripheral blood mononuclear cells were isolated and cultured to achieve macrophage differentiation. TLR4 and TLR7 were activated by lipopolysaccharide (LPS) or imiquimod in the presence/absence of allopregnanolone or related neurosteroids and pro-inflammatory markers were detected by ELISA or western blotting. Cultured human monocyte-derived-macrophages exhibited typical morphology, a mixed immune profile of both inflammatory and anti-inflammatory markers, with no sex difference at baseline. Allopregnanolone inhibited TLR4 activation in male and female donors, preventing LPS-induced elevations of TNF-α, MCP-1, pCREB and pSTAT1. In contrast, 3α,5α-THDOC and SGE-516 inhibited the TLR4 pathway activation in female, but not male donors. Allopregnanolone completely inhibited TLR7 activation by imiquimod, blocking IL-1-β, IL-6, pSTAT1 and pIRF7 elevations in females only. 3α,5α-THDOC and SGE-516 partially inhibited TLR7 activation, only in female donors. The results indicate that allopregnanolone inhibits TLR4 and TLR7 activation in cultured human macrophages resulting in diminished cytokine/chemokine production. Allopregnanolone inhibition of TLR4 activation was found in males and females, but inhibition of TLR7 signals exhibited specificity for female donors. 3α,5α-THDOC and SGE-516 inhibited TLR4 and TLR7 pathways only in females. These studies demonstrate anti-inflammatory effects of allopregnanolone in human macrophages for the first time and suggest that inhibition of pro-inflammatory cytokines/chemokines may contribute to its therapeutic actions.
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Affiliation(s)
- Irina Balan
- Department of Psychiatry, Department of Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, United States
| | - Laure Aurelian
- Stanford University School of Medicine, Stanford, CA, United States
| | - Kimberly S. Williams
- Department of Neurology, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, United States
| | - Brian Campbell
- Translational Sciences, Sage Therapeutics Inc., Cambridge, MA, United States
| | - Rick B. Meeker
- Department of Neurology, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, United States
| | - A. Leslie Morrow
- Department of Psychiatry, Department of Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, United States
- *Correspondence: A. Leslie Morrow,
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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] [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.
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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.
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10
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Balan I, Aurelian L, Schleicher R, Boero G, O'Buckley T, Morrow AL. Neurosteroid allopregnanolone (3α,5α-THP) inhibits inflammatory signals induced by activated MyD88-dependent toll-like receptors. Transl Psychiatry 2021; 11:145. [PMID: 33637705 PMCID: PMC7909379 DOI: 10.1038/s41398-021-01266-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 01/21/2021] [Accepted: 02/02/2021] [Indexed: 02/08/2023] Open
Abstract
We have shown that endogenous neurosteroids, including pregnenolone and 3α,5α-THP inhibit toll-like receptor 4 (TLR4) signal activation in mouse macrophages and the brain of alcohol-preferring (P) rat, which exhibits innate TLR4 signal activation. The current studies were designed to examine whether other activated TLR signals are similarly inhibited by 3α,5α-THP. We report that 3α,5α-THP inhibits selective agonist-mediated activation of TLR2 and TLR7, but not TLR3 signaling in the RAW246.7 macrophage cell line. The TLR4 and TLR7 signals are innately activated in the amygdala and NAc from P rat brains and inhibited by 3α,5α-THP. The TLR2 and TLR3 signals are not activated in P rat brain and they are not affected by 3α,5α-THP. Co-immunoprecipitation studies indicate that 3α,5α-THP inhibits the binding of MyD88 with TLR4 or TLR7 in P rat brain, but the levels of TLR4 co-precipitating with TRIF are not altered by 3α,5α-THP treatment. Collectively, the data indicate that 3α,5α-THP inhibits MyD88- but not TRIF-dependent TLR signal activation and the production of pro-inflammatory mediators through its ability to block TLR-MyD88 binding. These results have applicability to many conditions involving pro-inflammatory TLR activation of cytokines, chemokines, and interferons and support the use of 3α,5α-THP as a therapeutic for inflammatory disease.
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Affiliation(s)
- Irina Balan
- Department of Psychiatry, Department of Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA
| | - Laure Aurelian
- Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Riana Schleicher
- Department of Psychiatry, Department of Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA
| | - Giorgia Boero
- Department of Psychiatry, Department of Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA
| | - Todd O'Buckley
- Department of Psychiatry, Department of Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA
| | - A Leslie Morrow
- Department of Psychiatry, Department of Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA.
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11
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Boero G, Tyler RE, Todd CA, O'Buckley TK, Balan I, Besheer J, Morrow AL. (3α,5α)3-hydroxypregnan-20-one (3α,5α-THP) regulation of hypothalamic and extrahypothalamic corticotropin releasing factor (CRF): Sexual dimorphism and brain region specificity in Sprague Dawley rats. Neuropharmacology 2021; 186:108463. [PMID: 33460689 DOI: 10.1016/j.neuropharm.2021.108463] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 01/07/2021] [Accepted: 01/10/2021] [Indexed: 11/25/2022]
Abstract
CRF is the main activator of the hypothalamic-pituitary-adrenal (HPA) axis in response to stress. CRF neurons are found mainly in the hypothalamus, but CRF positive cells and CRF1 receptors are also found in extrahypothalamic structures, including amygdala (CeA), hippocampus, NAc and VTA. CRF release in the hypothalamus is regulated by inhibitory GABAergic interneurons and extrahypothalamic glutamatergic inputs, and disruption of this balance is found in stress-related disorders and addiction. (3α,5α)3-hydroxypregnan-20-one (3α,5α-THP), the most potent positive modulator of GABAA receptors, attenuates the stress response reducing hypothalamic CRF mRNA expression and ACTH and corticosterone serum levels. In this study, we explored 3α,5α-THP regulation of hypothalamic and extrahypothalamic CRF mRNA and peptide expression, in male and female Sprague Dawley rats, following vehicle or 3α,5α-THP administration (15 mg/kg). In the hypothalamus, we found sex differences in CRF mRNA expression (females +74%, p < 0.01) and CRF peptide levels (females -71%, p < 0.001). 3α,5α-THP administration reduced hypothalamic CRF mRNA expression only in males (-50%, p < 0.05) and did not alter CRF peptide expression in either sex. In hippocampus and CeA, 3α,5α-THP administration reduced CRF peptide concentrations only in the male (hippocampus -29%, p < 0.05; CeA -62%, p < 0.01). In contrast, 3α,5α-THP injection increased CRF peptide concentration in the VTA of both males (+32%, p < 0.01) and females (+26%, p < 0.01). The results show sex and region-specific regulation of CRF signals and the response to 3α,5α-THP administration. This data may be key to successful development of therapeutic approaches for stress-related disorders and addiction.
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Affiliation(s)
- Giorgia Boero
- Department of Psychiatry, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA; Department of Pharmacology, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA; Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA
| | - Ryan E Tyler
- Department of Pharmacology, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA; Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA
| | - Caroline A Todd
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA
| | - Todd K O'Buckley
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA
| | - Irina Balan
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA
| | - Joyce Besheer
- Department of Psychiatry, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA; Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA
| | - A Leslie Morrow
- Department of Psychiatry, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA; Department of Pharmacology, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA; Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC, 27599, USA.
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12
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Hao F, Tam W, Hu X, Tan W, Jiang L, Jiang X, Zhang L, Zhao X, Zou Y, Hu Y, Luo X, McIntyre RS, Quek T, Tran BX, Zhang Z, Pham HQ, Ho CSH, Ho RC. A quantitative and qualitative study on the neuropsychiatric sequelae of acutely ill COVID-19 inpatients in isolation facilities. Transl Psychiatry 2020; 10:355. [PMID: 33077738 PMCID: PMC7570419 DOI: 10.1038/s41398-020-01039-2] [Citation(s) in RCA: 112] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 09/12/2020] [Accepted: 10/01/2020] [Indexed: 12/18/2022] Open
Abstract
This study examined the neuropsychiatric sequelae of acutely ill patients with coronavirus disease 2019 (COVID-19) infection who received treatment in hospital isolation wards during the COVID-19 pandemic. Ten COVID-19 patients who received treatment in various hospitals in Chongqing, China; 10 age- and gender-matched psychiatric patients; and 10 healthy control participants residing in the same city were recruited. All participants completed a survey that collected information on demographic data, physical symptoms in the past 14 days and psychological parameters. Face-to-face interviews with COVID-19 patients were also performed using semi-structured questions. Among the COVID-19 patients, 40% had abnormal findings on the chest computed topography scan, 20% had dysosmia, 10% had dysgeusia, and 80% had repeated positivity on COVID-19 reverse-transcription polymerase chain reaction testing. COVID-19 and psychiatric patients were significantly more worried about their health than healthy controls (p = 0.019). A greater proportion of COVID-19 patients experienced impulsivity (p = 0.016) and insomnia (p = 0.039) than psychiatric patients and healthy controls. COVID-19 patients reported a higher psychological impact of the outbreak than psychiatric patients and healthy controls, with half of them having clinically significant symptoms of posttraumatic stress disorder. COVID-19 and psychiatric patients had higher levels of depression, anxiety and stress than healthy controls. Three themes emerged from the interviews with COVID-19 patients: (i) The emotions experienced by patients after COVID-19 infection (i.e., shock, fear, despair, hope, and boredom); (ii) the external factors that affected patients' mood (i.e., discrimination, medical expenses, care by healthcare workers); and (iii) coping and self-help behavior (i.e., distraction, problem-solving and online support). The future direction in COVID-19 management involves the development of a holistic inpatient service to promote immune and psychological resilience.
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Affiliation(s)
- Fengyi Hao
- grid.440187.eThe First People’s Hospital of Chongqing Liang Jiang New Area, Chongqing, China
| | - Wilson Tam
- grid.4280.e0000 0001 2180 6431Alice Lee Centre for Nursing Studies, National University of Singapore, Singapore, Singapore
| | - Xiaoyu Hu
- grid.452206.7First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Wanqiu Tan
- National University of Singapore (Chongqing) Research Institute, Chongqing, China
| | - Li Jiang
- grid.440187.eThe First People’s Hospital of Chongqing Liang Jiang New Area, Chongqing, China
| | - Xiaojiang Jiang
- grid.440187.eThe First People’s Hospital of Chongqing Liang Jiang New Area, Chongqing, China
| | - Ling Zhang
- grid.440187.eThe First People’s Hospital of Chongqing Liang Jiang New Area, Chongqing, China
| | - Xinling Zhao
- grid.440187.eThe First People’s Hospital of Chongqing Liang Jiang New Area, Chongqing, China
| | - Yiran Zou
- grid.440187.eThe First People’s Hospital of Chongqing Liang Jiang New Area, Chongqing, China
| | - Yirong Hu
- grid.440187.eThe First People’s Hospital of Chongqing Liang Jiang New Area, Chongqing, China
| | - Xi Luo
- grid.414048.d0000 0004 1799 2720Department of Neurology, Daping Hospital, Army Medical University, Chongqing, 400042 China
| | - Roger S. McIntyre
- grid.17063.330000 0001 2157 2938Mood Disorders Psychopharmacology Unit, University Health Network, University of Toronto, Toronto, Canada
| | - Travis Quek
- grid.4280.e0000 0001 2180 6431Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119077 Singapore
| | - Bach Xuan Tran
- grid.56046.310000 0004 0642 8489Institute for Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, 100000 Vietnam ,grid.21107.350000 0001 2171 9311Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205 USA
| | - Zhisong Zhang
- grid.440755.70000 0004 1793 4061Faculty of Education, Huaibei Normal University, Huaibei, 235000 China
| | - Hai Quang Pham
- grid.444918.40000 0004 1794 7022Institute for Global Health Innovations, Duy Tan University, Da Nang, Vietnam ,grid.444918.40000 0004 1794 7022Faculty of Medicine, Duy Tan University, Da Nang, Vietnam
| | - Cyrus S. H. Ho
- grid.4280.e0000 0001 2180 6431Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119077 Singapore ,grid.410759.e0000 0004 0451 6143Department of Psychological Medicine, National University Health System, Singapore, Singapore
| | - Roger C.M. Ho
- grid.4280.e0000 0001 2180 6431Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119077 Singapore ,grid.4280.e0000 0001 2180 6431Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore, 119077 Singapore
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13
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Gondré-Lewis MC, Bassey R, Blum K. Pre-clinical models of reward deficiency syndrome: A behavioral octopus. Neurosci Biobehav Rev 2020; 115:164-188. [PMID: 32360413 DOI: 10.1016/j.neubiorev.2020.04.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 04/08/2020] [Accepted: 04/20/2020] [Indexed: 12/15/2022]
Abstract
Individuals with mood disorders or with addiction, impulsivity and some personality disorders can share in common a dysfunction in how the brain perceives reward, where processing of natural endorphins or the response to exogenous dopamine stimulants is impaired. Reward Deficiency Syndrome (RDS) is a polygenic trait with implications that suggest cross-talk between different neurological systems that include the known reward pathway, neuroendocrine systems, and motivational systems. In this review we evaluate well-characterized animal models for their construct validity and as potential models for RDS. Animal models used to study substance use disorder, major depressive disorder (MDD), early life stress, immune dysregulation, attention deficit hyperactivity disorder (ADHD), post traumatic stress disorder (PTSD), compulsive gambling and compulsive eating disorders are discussed. These disorders recruit underlying reward deficiency mechanisms in multiple brain centers. Because of the widespread and remarkable array of associated/overlapping behavioral manifestations with a common root of hypodopaminergia, the basic endophenotype recognized as RDS is indeed likened to a behavioral octopus. We conclude this review with a look ahead on how these models can be used to investigate potential therapeutics that target the underlying common deficiency.
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Affiliation(s)
- Marjorie C Gondré-Lewis
- Department of Anatomy, Howard University College of Medicine, 520 W Street, NW, Washington D.C., 20059, United States; Developmental Neuropsychopharmacology Laboratory, Howard University College of Medicine, 520 W Street, NW, Washington D.C., 20059, United States.
| | - Rosemary Bassey
- Developmental Neuropsychopharmacology Laboratory, Howard University College of Medicine, 520 W Street, NW, Washington D.C., 20059, United States; Department of Science Education, Donald and Barbara Zucker School of Medicine at Hofstra/ Northwell, 500 Hofstra University, Hempstead, NY 11549, United States
| | - Kenneth Blum
- Western University Health Sciences, Graduate College of Biomedical Sciences, Pomona, California, United States
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14
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Solanki N, Abijo T, Galvao C, Darius P, Blum K, Gondré-Lewis MC. Administration of a putative pro-dopamine regulator, a neuronutrient, mitigates alcohol intake in alcohol-preferring rats. Behav Brain Res 2020; 385:112563. [PMID: 32070691 DOI: 10.1016/j.bbr.2020.112563] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 02/13/2020] [Accepted: 02/14/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND Excessive alcohol intake is a serious but preventable public health problem in the United States and worldwide. Alcohol and other substance use disorders occur co-morbid with more generalized reward deficiency disorders, characterized by a reduction in dopamine (DA) signaling within the reward pathway, and classically associated with increased impulsivity, risk taking and subsequent drug seeking behavior. It is postulated that increasing dopamine availability and thus restoring DA homeostasis in the mesocorticolimbic system could reduce the motivation to seek and consume ethanol. Here, we treated animals with a neuro-nutrient, KB220Z also known as Synaptamine, designed to augment DA signaling. METHOD KB220Z was administered to genetically alcohol-preferring (P) adult male and female rats by oral gavage (PO), intraperioneally (IP), or subcutaneously (SQ) for 4 consecutive days at a 3.4 mL/Kg rat equivalent dose and compared to saline (SQ, IP) or water (PO) controls. Subsequent to treatment, lever pressing and consumption of 10 % ethanol or control 3% sucrose during operant responding was assessed using a drinking in the dark multiple scheduled access (DIDMSA) binge drinking protocol. Locomotor and elevated zero maze activity, and DRD2 mRNA expression via in situ hybridization (ISH) were assessed independently following 4 days of a SQ regimen of KB220Z. RESULTS KB220Z administered via IP and SQ markedly and immediately reduced binge drinking of 10 % ethanol in both male and female rats whereas PO administration took at least 3 days to decrease lever pressing for ethanol in both male and female rats. There was no effect of SQ KB220Z on 3% sucrose drinking. Elevated activity in the open field was significantly decreased, and time spent in the open arm of the EZM was moderately reduced. The regimen of SQ KB220Z did not impact the number of DRD2 punctae in neurons of the NAc, but the NAc shell expressed more DRD2 mRNA/cell than NAc core independent of KB220Z. CONCLUSION KB220Z attenuates ethanol drinking and other RDS behaviors in P rats possibly by acting on the dopaminergic system, but not by effecting an increase in NAc DRD2 mRNA expression.
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Affiliation(s)
- Naimesh Solanki
- Department of Anatomy, Howard University, Washington D.C., 20059, USA; Developmental Neuropsychopharmacology Laboratory, Howard University College of Medicine, Washington D.C., 20059, USA
| | - Tomilowo Abijo
- Department of Anatomy, Howard University, Washington D.C., 20059, USA; Developmental Neuropsychopharmacology Laboratory, Howard University College of Medicine, Washington D.C., 20059, USA
| | - Carine Galvao
- Department of Anatomy, Howard University, Washington D.C., 20059, USA; Developmental Neuropsychopharmacology Laboratory, Howard University College of Medicine, Washington D.C., 20059, USA
| | - Philippe Darius
- Department of Anatomy, Howard University, Washington D.C., 20059, USA; Developmental Neuropsychopharmacology Laboratory, Howard University College of Medicine, Washington D.C., 20059, USA
| | - Kenneth Blum
- Western University Health Science Center, Graduate School of Biomedical Sciences, Pomona, CA, 91766 USA; Institute of Psychology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Marjorie C Gondré-Lewis
- Department of Anatomy, Howard University, Washington D.C., 20059, USA; Developmental Neuropsychopharmacology Laboratory, Howard University College of Medicine, Washington D.C., 20059, USA.
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15
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Morrow AL, Boero G, Porcu P. A Rationale for Allopregnanolone Treatment of Alcohol Use Disorders: Basic and Clinical Studies. Alcohol Clin Exp Res 2020; 44:320-339. [PMID: 31782169 PMCID: PMC7018555 DOI: 10.1111/acer.14253] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 11/19/2019] [Indexed: 12/17/2022]
Abstract
For many years, research from around the world has suggested that the neuroactive steroid (3α,5α)-3-hydroxypregnan-20-one (allopregnanolone or 3α,5α-THP) may have therapeutic potential for treatment of various symptoms of alcohol use disorders (AUDs). In this critical review, we systematically address all the evidence that supports such a suggestion, delineate the etiologies of AUDs that are addressed by treatment with allopregnanolone or its precursor pregnenolone, and the rationale for treatment of various components of the disease based on basic science and clinical evidence. This review presents a theoretical framework for understanding how endogenous steroids that regulate the effects of stress, alcohol, and the innate immune system could play a key role in both the prevention and the treatment of AUDs. We further discuss cautions and limitations of allopregnanolone or pregnenolone therapy with suggestions regarding the management of risk and the potential for helping millions who suffer from AUDs.
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Affiliation(s)
- A. Leslie Morrow
- Department of Psychiatry, Department of Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC 27599
| | - Giorgia Boero
- Department of Psychiatry, Department of Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, NC 27599
| | - Patrizia Porcu
- Neuroscience Institute, National Research Council of Italy (CNR), Cagliari, Italy
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16
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Aurelian L, Balan I. GABA AR α2-activated neuroimmune signal controls binge drinking and impulsivity through regulation of the CCL2/CX3CL1 balance. Psychopharmacology (Berl) 2019; 236:3023-3043. [PMID: 31030249 DOI: 10.1007/s00213-019-05220-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 03/04/2019] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND PURPOSE Toll-like receptors (TLRs) are a family of innate immune system receptors that respond to pathogen-derived and tissue damage-related ligands and are increasingly recognized for their impact on homeostasis and its dysregulation in the nervous system. TLR signaling participates in brain injury and addiction, but its role in the alcohol-seeking behavior, which initiates alcohol drinking, is still poorly understood. In this review, we discuss our findings designed to elucidate the potential contribution of the activated TLR4 signal located in neurons, on impulsivity and the predisposition to initiate alcohol drinking (binge drinking). RESULTS Our findings indicate that the TLR4 signal is innately activated in neurons from alcohol-preferring subjects, identifying a genetic contribution to the regulation of impulsivity and the alcohol-seeking propensity. Signal activation is through the non-canonical, previously unknown, binding of TLR4 to the α2 subunit of the γ-aminobutyric 2 acid A receptor (GABAAR α2). Activation is sustained by the stress hormone corticotrophin-releasing factor (CRF) and additional still poorly recognized ligand/scaffold proteins. Focus is on the effect of TLR4 signal activation on the balance between pro- and anti-inflammatory chemokines [chemokine (C-C motif) ligand 2 (CCL2)/chemokine (C-X3-C motif) ligand 1 (CX3CL1)] and its effect on binge drinking. CONCLUSION The results are discussed within the context of current findings on the distinct activation and functions of TLR signals located in neurons, as opposed to immune cells. They indicate that the balance between pro- and anti-inflammatory TLR4 signaling plays a major role in binge drinking. These findings have major impact on future basic and translational research, including the development of potential therapeutic and preventative strategies.
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Affiliation(s)
- Laure Aurelian
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA. .,Stanford University School of Medicine OFDD, Stanford, CA, 94305, USA.
| | - Irina Balan
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.,Department of Psychiatry and Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
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17
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Endogenous Neurosteroid (3α,5α)3-Hydroxypregnan-20-one Inhibits Toll-like-4 Receptor Activation and Pro-inflammatory Signaling in Macrophages and Brain. Sci Rep 2019; 9:1220. [PMID: 30718548 PMCID: PMC6362084 DOI: 10.1038/s41598-018-37409-6] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 10/05/2018] [Indexed: 12/31/2022] Open
Abstract
The endogenous neurosteroid (3α,5α)3-hydroxypregnan-20-one (3α,5α-THP, allopregnanolone) has protective activity in animal models of alcoholism, depression, traumatic brain injury, schizophrenia, multiple sclerosis, and Alzheimer’s disease that is poorly understood. Because these conditions involve proinflammatory signaling through toll-like receptors (TLRs), we examined the effects of 3α,5α-THP, and pregnenolone on TLR4 activation in both the periphery and the central nervous system (CNS). We used monocytes/macrophages (RAW264.7) as a model of peripheral immune signaling and studied innately activated TLR4 in the ventral tegmental area (VTA) of selectively bred alcohol-preferring (P) rats. LPS activated the TLR4 pathway in RAW264.7 cells as evidenced by increased levels of p-TAK1, TRAF6, NF-κB p50, phospho-NF-κB- p65, pCREB, HMGB1, and inflammatory mediators, including MCP-1 and TNFα. Both 3α,5α-THP and pregnenolone (0.5–1.0μM) substantially (~80%) inhibited these effects, indicating pronounced inhibition of TLR4 signaling. The mechanism of inhibition appears to involve blockade of TLR4/MD-2 protein interactions in RAW246.7 cells. In VTA, 3α,5α-THP (15 mg/kg, IP) administration reduced TRAF6 (~20%), CRF (~30%), and MCP-1 (~20%) levels, as well as TLR4 binding to GABAA receptor α2 subunits (~60%) and MyD88 (~40%). The data suggest that inhibition of proinflammatory neuroimmune signaling underlies protective effects of 3α,5α-THP in immune cells and brain, apparently involving blocking of protein-protein interactions that initiate TLR4-dependent signaling. Inhibition of pro-inflammatory TLR4 activation represents a new mechanism of 3α,5α-THP action in the periphery and the brain.
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18
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The GABA A Receptor α2 Subunit Activates a Neuronal TLR4 Signal in the Ventral Tegmental Area that Regulates Alcohol and Nicotine Abuse. Brain Sci 2018; 8:brainsci8040072. [PMID: 29690521 PMCID: PMC5924408 DOI: 10.3390/brainsci8040072] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 04/04/2018] [Accepted: 04/18/2018] [Indexed: 01/06/2023] Open
Abstract
Alcoholism initiates with episodes of excessive alcohol drinking, known as binge drinking, which is one form of excessive drinking (NIAAA Newsletter, 2004) that is related to impulsivity and anxiety (Ducci et al., 2007; Edenberg et al., 2004) and is also predictive of smoking status. The predisposition of non-alcohol exposed subjects to initiate binge drinking is controlled by neuroimmune signaling that includes an innately activated neuronal Toll-like receptor 4 (TLR4) signal. This signal also regulates cognitive impulsivity, a heritable trait that defines drug abuse initiation. However, the mechanism of signal activation, its function in dopaminergic (TH+) neurons within the reward circuitry implicated in drug-seeking behavior [viz. the ventral tegmental area (VTA)], and its contribution to nicotine co-abuse are still poorly understood. We report that the γ-aminobutyric acidA receptor (GABAAR) α2 subunit activates the TLR4 signal in neurons, culminating in the activation (phosphorylation/nuclear translocation) of cyclic AMP response element binding (CREB) but not NF-kB transcription factors and the upregulation of corticotropin-releasing factor (CRF) and tyrosine hydroxylase (TH). The signal is activated through α2/TLR4 interaction, as evidenced by co-immunoprecipitation, and it is present in the VTA from drug-untreated alcohol-preferring P rats. VTA infusion of neurotropic herpes simplex virus (HSV) vectors for α2 (pHSVsiLA2) or TLR4 (pHSVsiTLR4) but not scrambled (pHSVsiNC) siRNA inhibits signal activation and both binge alcohol drinking and nicotine sensitization, suggesting that the α2-activated TLR4 signal contributes to the regulation of both alcohol and nicotine abuse.
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