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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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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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Li S, Lu C, Kang L, Li Q, Chen H, Zhang H, Tang Z, Lin Y, Bai M, Xiong P. Study on correlations of BDNF, PI3K, AKT and CREB levels with depressive emotion and impulsive behaviors in drug-naïve patients with first-episode schizophrenia. BMC Psychiatry 2023; 23:225. [PMID: 37013544 PMCID: PMC10071748 DOI: 10.1186/s12888-023-04718-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 03/25/2023] [Indexed: 04/05/2023] Open
Abstract
BACKGROUND The pathogenesis of schizophrenia is still unknown. Nearly a half of schizophrenic patients have depressive symptoms and even some impulsive behaviors. The definite diagnosis of schizophrenia is an immense challenge. Molecular biology plays an essential role in the research on the pathogenesis of schizophrenia. OBJECTIVE This study aims to analyze the correlations of serum protein factor levels with depressive emotion and impulsive behaviors in drug-naïve patients with first-episode schizophrenia. METHODS Seventy drug-naïve patients with first-episode schizophrenia and sixty-nine healthy volunteers from the health check center in the same period participated in this study. In both the patient group and control group, brain-derived neurotrophic factor (BDNF), phosphatidylin-ositol-3-kinase (PI3K), protein kinase B (AKT), and cAMP-response element binding protein (CREB) levels in the peripheral blood were tested by enzyme-linked immunosorbent assay (ELISA). The depressive emotion and impulsive behaviors were evaluated with Chinese versions of the Calgary Depression Scale for Schizophrenia (CDSS) and Short UPPS-P Impulsive Behavior Scale (S-UPPS-P), respectively. RESULTS The serum levels of BDNF, PI3K, and CREB in the patient group were lower than those in the control group, while AKT level, total CDSS score and total S-UPPS-P score were all higher. In the patient group, total CDSS score, and total S-UPPS-P score were both correlated negatively with BDNF, PI3K, and CREB levels but positively with AKT level, and the lack-of-premeditation (PR) sub-scale score was not significantly correlated with BDNF, PI3K, AKT, and CREB levels. CONCLUSION Our study results showed that the peripheral blood levels of BDNF, PI3K, AKT, and CREB in drug-naïve patients with first-episode schizophrenia were significantly different from those in the control group. The levels of these serum protein factors are promising biomarkers to predict schizophrenic depression and impulsive behaviors.
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Affiliation(s)
- Shan Li
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Cailian Lu
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Lin Kang
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Qianqian Li
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Hongxu Chen
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Han Zhang
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Ziling Tang
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Yanwen Lin
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Meiyan Bai
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Peng Xiong
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China.
- Yunnan Clinical Research Center for Mental Disorders, First Affiliated Hospital of Kunming Medical University, Kunming, China.
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Wang JQ, Liu YR, Xia QR, Liang J, Wang JL, Li J. Functional roles, regulatory mechanisms and theranostics applications of ncRNAs in alcohol use disorder. Int J Biol Sci 2023; 19:1316-1335. [PMID: 36923934 PMCID: PMC10008696 DOI: 10.7150/ijbs.81518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 02/02/2023] [Indexed: 03/14/2023] Open
Abstract
Alcohol use disorder (AUD) is one of the most prevalent neuropsychological disorders worldwide, and its pathogenesis is convoluted and poorly understood. There is considerable evidence demonstrating significant associations between multiple heritable factors and the onset and progression of AUD. In recent years, a substantial body of research conducted by emerging biotechnologies has increasingly highlighted the crucial roles of noncoding RNAs (ncRNAs) in the pathophysiology of mental diseases. As in-depth understanding of ncRNAs and their mechanisms of action, they have emerged as prospective diagnostic indicators and preclinical therapeutic targets for a variety of psychiatric illness, including AUD. Of note, dysregulated expression of ncRNAs such as circRNAs, lncRNAs and miRNAs was routinely found in AUD individuals, and besides, exogenous regulation of partial ncRNAs has also been shown to be effective in ameliorating alcohol preference and excessive alcohol consumption. However, the exact molecular mechanism still remains elusive. Herein, we systematically summarized current knowledge regarding alterations in the expression of certain ncRNAs as well as their-mediated regulatory mechanisms in individuals with AUD. And finally, we detailedly reviewed the potential theranostics applications of gene therapy agents targeting ncRNAs in AUD mice. Overall, a deeper comprehension of functional roles and biological mechanisms of ncRNAs may make significant contributions to the accurate diagnosis and effective treatment of AUD.
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Affiliation(s)
- Jie-Quan Wang
- Department of Pharmacy, Affiliated Psychological Hospital of Anhui Medical University, Hefei, 230000, China.,Department of Pharmacy, Hefei Fourth People's Hospital, Hefei, 230000, China.,Psychopharmacology Research Laboratory, Anhui Mental Health Center, Hefei, 230000, China.,Anhui Clinical Research Center for Mental Disorders, Hefei,230000, China
| | - Ya-Ru Liu
- Department of Pharmacy, First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China.,The Grade 3 Pharmaceutical Chemistry Laboratory of State Administration of Traditional Chinese Medicine, Hefei, 230022, China
| | - Qing-Rong Xia
- Department of Pharmacy, Affiliated Psychological Hospital of Anhui Medical University, Hefei, 230000, China.,Department of Pharmacy, Hefei Fourth People's Hospital, Hefei, 230000, China.,Psychopharmacology Research Laboratory, Anhui Mental Health Center, Hefei, 230000, China.,Anhui Clinical Research Center for Mental Disorders, Hefei,230000, China
| | - Jun Liang
- Department of Pharmacy, Affiliated Psychological Hospital of Anhui Medical University, Hefei, 230000, China.,Department of Pharmacy, Hefei Fourth People's Hospital, Hefei, 230000, China.,Psychopharmacology Research Laboratory, Anhui Mental Health Center, Hefei, 230000, China.,Anhui Clinical Research Center for Mental Disorders, Hefei,230000, China
| | - Jin-Liang Wang
- Department of Pharmacy, Affiliated Psychological Hospital of Anhui Medical University, Hefei, 230000, China.,Department of Pharmacy, Hefei Fourth People's Hospital, Hefei, 230000, China.,Psychopharmacology Research Laboratory, Anhui Mental Health Center, Hefei, 230000, China.,Anhui Clinical Research Center for Mental Disorders, Hefei,230000, China
| | - Jun Li
- Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, 230032, China
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Bo JH, Wang JX, Wang XL, Jiao Y, Jiang M, Chen JL, Hao WY, Chen Q, Li YH, Ma ZL, Zhu GQ. Dexmedetomidine Attenuates Lipopolysaccharide-Induced Sympathetic Activation and Sepsis via Suppressing Superoxide Signaling in Paraventricular Nucleus. Antioxidants (Basel) 2022; 11:antiox11122395. [PMID: 36552603 PMCID: PMC9774688 DOI: 10.3390/antiox11122395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 11/15/2022] [Accepted: 11/29/2022] [Indexed: 12/07/2022] Open
Abstract
Sympathetic overactivity contributes to the pathogenesis of sepsis. The selective α2-adrenergic receptor agonist dexmedetomidine (DEX) is widely used for perioperative sedation and analgesia. We aimed to determine the central roles and mechanisms of DEX in attenuating sympathetic activity and inflammation in sepsis. Sepsis was induced by a single intraperitoneal injection of lipopolysaccharide (LPS) in rats. Effects of DEX were investigated 24 h after injection of LPS. Bilateral microinjection of DEX in the paraventricular nucleus (PVN) attenuated LPS-induced sympathetic overactivity, which was attenuated by the superoxide dismutase inhibitor DETC, cAMP analog db-cAMP or GABAA receptor antagonist gabazine. Superoxide scavenger tempol, NADPH oxidase inhibitor apocynin, adenylate cyclase inhibitor SQ22536 or PKA inhibitor Rp-cAMP caused similar effects to DEX in attenuating LPS-induced sympathetic activation. DEX inhibited LPS-induced superoxide and cAMP production, as well as NADPH oxidase, adenylate cyclase and PKA activation. The roles of DEX in reducing superoxide production and NADPH oxidase activation were attenuated by db-cAMP or gabazine. Intravenous infusion of DEX inhibited LPS-induced sympathetic overactivity, NOX activation, superoxide production, TNF-α and IL-1β upregulation in the PVN and plasma, as well as lung and renal injury, which were attenuated by the PVN microinjection of yohimbine and DETC. We conclude that activation of α2-adrenergic receptors with DEX in the PVN attenuated LPS-induced sympathetic overactivity by reducing NADPH oxidase-dependent superoxide production via both inhibiting adenylate cyclase-cAMP-PKA signaling and activating GABAA receptors. The inhibition of NADPH oxidase-dependent superoxide production in the PVN partially contributes to the roles of intravenous infusion of DEX in attenuating LPS-induced sympathetic activation, oxidative stress and inflammation.
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Affiliation(s)
- Jin-Hua Bo
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Physiology, Nanjing Medical University, Nanjing 211166, China
- Department of Anesthesiology, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
| | - Jing-Xiao Wang
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Physiology, Nanjing Medical University, Nanjing 211166, China
| | - Xiao-Li Wang
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Physiology, Nanjing Medical University, Nanjing 211166, China
| | - Yang Jiao
- Department of Anesthesiology, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
| | - Ming Jiang
- Department of Anesthesiology, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
| | - Jun-Liu Chen
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Physiology, Nanjing Medical University, Nanjing 211166, China
| | - Wen-Yuan Hao
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Physiology, Nanjing Medical University, Nanjing 211166, China
| | - Qi Chen
- Department of Pathophysiology, Nanjing Medical University, Nanjing 211166, China
| | - Yue-Hua Li
- Department of Pathophysiology, Nanjing Medical University, Nanjing 211166, China
| | - Zheng-Liang Ma
- Department of Anesthesiology, The Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
- Correspondence: (Z.-L.M.); (G.-Q.Z.)
| | - Guo-Qing Zhu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Department of Physiology, Nanjing Medical University, Nanjing 211166, China
- Correspondence: (Z.-L.M.); (G.-Q.Z.)
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Hernandez CM, McQuail JA, Ten Eyck TW, Wheeler AR, Labiste CC, Setlow B, Bizon J. GABA B receptors in prelimbic cortex and basolateral amygdala differentially influence intertemporal decision making and decline with age. Neuropharmacology 2022; 209:109001. [PMID: 35189132 DOI: 10.1016/j.neuropharm.2022.109001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 02/07/2022] [Accepted: 02/15/2022] [Indexed: 11/25/2022]
Abstract
The ability to decide adaptively between immediate vs. delayed gratification (intertemporal choice) is critical for well-being and is associated with a range of factors that influence quality of life. In contrast to young adults, many older adults show enhanced preference for delayed gratification; however, the neural mechanisms underlying this age difference in intertemporal choice are largely un-studied. Changes in signaling through GABAB receptors (GABABRs) mediate several age-associated differences in cognitive processes linked to intertemporal choice. The current study used a rat model to determine how GABABRs in two brain regions known to regulate intertemporal choice (prelimbic cortex; PrL and basolateral amygdala; BLA) contribute to age differences in this form of decision making in male rats. As in humans, aged rats showed enhanced preference for large, delayed over small, immediate rewards during performance in an intertemporal choice task in operant test chambers. Activation of PrL GABABRs via microinfusion of the agonist baclofen increased choice of large, delayed rewards in young adult rats but did not influence choice in aged rats. Conversely, infusion of baclofen into the BLA strongly reduced choice of large, delayed rewards in both young adult and aged rats. Aged rats further showed a significant reduction in expression of GABABR1 subunit isoforms in the prefrontal cortex, a discovery that is consonant with the null effect of intra-PrL baclofen on intertemporal choice in aged rats. In contrast, expression of GABABR subunits was generally conserved with age in the BLA. Jointly, these findings elucidate a role for GABABRs in intertemporal choice and identify fundamental features of brain maturation and aging that mediate an improved ability to delay gratification.
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Affiliation(s)
- Caesar M Hernandez
- Department of Neuroscience, University of Florida, Gainesville, FL, 32610, USA; Department of Neurobiology, The University of Alabama at Birmingham, Birmingham, AL, 35294, USA; McKnight Brain Institute, University of Florida, Gainesville, FL, 32610, USA
| | - Joseph A McQuail
- Department of Neuroscience, University of Florida, Gainesville, FL, 32610, USA; Department of Pharmacology, Physiology and Neuroscience, University of South Carolina School of Medicine - Columbia, Columbia, SC, 29208, USA
| | - Tyler W Ten Eyck
- Department of Neuroscience, University of Florida, Gainesville, FL, 32610, USA
| | - Alexa-Rae Wheeler
- Department of Neuroscience, University of Florida, Gainesville, FL, 32610, USA
| | - Chase C Labiste
- Department of Neuroscience, University of Florida, Gainesville, FL, 32610, USA.
| | - Barry Setlow
- Department of Neuroscience, University of Florida, Gainesville, FL, 32610, USA; Department of Psychiatry, University of Florida, Gainesville, FL, 32610, USA; McKnight Brain Institute, University of Florida, Gainesville, FL, 32610, USA
| | - Jennifer Bizon
- Department of Neuroscience, University of Florida, Gainesville, FL, 32610, USA; McKnight Brain Institute, University of Florida, Gainesville, FL, 32610, USA
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Liu J, Li JX, Wu R. Toll-Like Receptor 4: A Novel Target to Tackle Drug Addiction? Handb Exp Pharmacol 2022; 276:275-290. [PMID: 35434747 PMCID: PMC9829382 DOI: 10.1007/164_2022_586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Drug addiction is a chronic brain disease characterized by compulsive drug-seeking and drug-taking behaviors despite the major negative consequences. Current well-established neuronal underpinnings of drug addiction have promoted the substantial progress in understanding this disorder. However, non-neuronal mechanisms of drug addiction have long been underestimated. Fortunately, increased evidence indicates that neuroimmune system, especially Toll-like receptor 4 (TLR4) signaling, plays an important role in the different stages of drug addiction. Drugs like opioids, psychostimulants, and alcohol activate TLR4 signaling and enhance the proinflammatory response, which is associated with drug reward-related behaviors. While extensive studies have shown that inhibition of TLR4 attenuated drug-related responses, there are conflicting findings implicating that TLR4 signaling may not be essential to drug addiction. In this chapter, preclinical and clinical studies will be discussed to further evaluate whether TLR4-based neuroimmune pharmacotherapy can be used to treat drug addiction. Furthermore, the possible mechanisms underlying the effects of TLR4 inhibition in modulating drug-related behaviors will also be discussed.
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Affiliation(s)
- Jianfeng Liu
- Brain Science and Advanced Technology Institute, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Jun-Xu Li
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, NY, USA,Corresponding authors: Dr. Jun-Xu Li, , Department of Pharmacology and Toxicology, University at Buffalo, The State University of New York, 955 Main Street, Buffalo, NY 14214. Tel: +1 716 829 2482; Fax: +1 716 829 2801 And Dr. Ruyan Wu, , School of Medicine, Yangzhou University, Yangzhou 225000, China
| | - Ruyan Wu
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, NY, USA,School of Medicine, Yangzhou University, Yangzhou, China,Corresponding authors: Dr. Jun-Xu Li, , Department of Pharmacology and Toxicology, University at Buffalo, The State University of New York, 955 Main Street, Buffalo, NY 14214. Tel: +1 716 829 2482; Fax: +1 716 829 2801 And Dr. Ruyan Wu, , School of Medicine, Yangzhou University, Yangzhou 225000, China
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9
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Li X, Chen W, Huang X, Jing W, Zhang T, Yu Q, Yu H, Li H, Tian Q, Ding Y, Lu Y. Synaptic dysfunction of Aldh1a1 neurons in the ventral tegmental area causes impulsive behaviors. Mol Neurodegener 2021; 16:73. [PMID: 34702328 PMCID: PMC8549305 DOI: 10.1186/s13024-021-00494-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 09/27/2021] [Indexed: 12/04/2022] Open
Abstract
Background Aldh1a1 neurons are a subtype of gamma-aminobutyric acid (GABA) inhibitory neurons that use Aldh1a1 rather than glutamate decarboxylase (GAD) as an enzyme for synthesizing GABA transmitters. However, the behaviors and circuits of this newly identified subtype of inhibitory interneurons remain unknown. Methods We generated a mutant mouse line in which cyclization recombination enzyme (CRE) was expressed under the control of the Aldh1a1 promotor (Aldh1a1-CRE mice). Using this mutant strain of mice together with the heterozygous male Alzheimer’s disease (AD) related model mice (APPswe/PSEN1dE9, or AD mice) and a genetically modified retrograde and anterograde synaptic tracing strategy, we have studied a specific synaptic circuit of Aldh1a1 neurons with system-level function and disease progression in AD mice. Results We demonstrate that Aldh1a1 neurons encode delay of gratification that measures self-control skills in decision making by projecting inhibitory synapses directly onto excitatory glutamate neurons in the intermediate lateral septum (EGNIS) and receiving synaptic inputs from layer 5b pyramidal neurons in the medial prefrontal cortex (L5PN). L5PN → Aldh1a1 synaptic transmission undergoes long-term potentiation (LTP). Pathway specific inhibition by either genetic silencing presynaptic terminals or antagonizing postsynaptic receptors impairs delay of gratification, resulting in the impulsive behaviors. Further studies show that reconstitution of Aldh1a1-deficient neurons with the expression of exogenous Aldh1a1 (eAldh1a1) restores Aldh1a1 → EGNIS synaptic transmission and rescues the impulsive behaviors in AD mice. Conclusions These results not only identify a specific function and circuit of Aldh1a1 neurons but also provide a cellular point of entry to an important but understudied synaptic mechanism for the induction of impulsive behaviors at an early stage of AD. Supplementary Information The online version contains supplementary material available at 10.1186/s13024-021-00494-9.
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Affiliation(s)
- Xinyan Li
- Department of Physiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 4030030, China.,Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Wenting Chen
- Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China.,Department of Neurobiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Xian Huang
- Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China.,Department of Pathophysiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Wei Jing
- Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China.,Department of Pathophysiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Tongmei Zhang
- Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China.,Department of Pathophysiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Quntao Yu
- Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China.,Department of Pathophysiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hongyan Yu
- Department of Physiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 4030030, China.,Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hao Li
- Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China.,Department of Pathophysiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Qing Tian
- Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China.,Department of Pathophysiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yumei Ding
- Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China. .,Department of Stomatology, School of Stomatology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Youming Lu
- Department of Physiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 4030030, China. .,Wuhan Center of Brain Science, Huazhong University of Science and Technology, Wuhan, 430030, China. .,Department of Pathophysiology, School of Basic Medicine and Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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10
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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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11
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Li Y, Chen L, Zhao W, Sun L, Zhang R, Zhu S, Xie K, Feng X, Wu X, Sun Z, Shu G, Wang S, Gao P, Zhu X, Wang L, Jiang Q. Food reward depends on TLR4 activation in dopaminergic neurons. Pharmacol Res 2021; 169:105659. [PMID: 33971268 DOI: 10.1016/j.phrs.2021.105659] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 04/30/2021] [Accepted: 04/30/2021] [Indexed: 01/07/2023]
Abstract
The rising prevalence of obesity and being overweight is a worldwide health concern. Food reward dysregulation is the basic factor for the development of obesity. Dopamine (DA) neurons in the ventral tegmental area (VTA) play a vital role in food reward. Toll-like receptor 4 (TLR4) is a transmembrane pattern recognition receptor that can be activated by saturated fatty acids. Here, we show that the deletion of TLR4 specifically in DA neurons increases body weight, increases food intake, and decreases food reward. Conditional deletion of TLR4 also decreased the activity of DA neurons while suppressing the expression of tyrosine hydroxylase (TH) in the VTA, which regulates the concentration of DA in the nucleus accumbens (NAc) to affect food reward. Meanwhile, AAV-Cre-GFP mediated VTA-specific TLR4-deficient mice recapitulates food reward of DAT-TLR4-KO mice. Food reward could be rescued by re-expressing TLR4 in VTA DA neurons. Moreover, effects of intra-VTA infusion of lauric acid (a saturated fatty acid with 12 carbon) on food reward were abolished in mice lacking TLR4 in DA neurons. Our study demonstrates the critical role of TLR4 signaling in regulating the activity of VTA DA neurons and the normal function of the mesolimbic DA system that may contribute to food reward.
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Affiliation(s)
- Yongxiang Li
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Lvshuang Chen
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Weijie Zhao
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Lijuan Sun
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Ruixue Zhang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Shuqing Zhu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Kailai Xie
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Xiajie Feng
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Xin Wu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Zhonghua Sun
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Gang Shu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Songbo Wang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Ping Gao
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Xiaotong Zhu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Lina Wang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China.
| | - Qingyan Jiang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China.
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12
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Jiménez-González A, Gómez-Acevedo C, Ochoa-Aguilar A, Chavarría A. The Role of Glia in Addiction: Dopamine as a Modulator of Glial Responses in Addiction. Cell Mol Neurobiol 2021; 42:2109-2120. [PMID: 34057683 DOI: 10.1007/s10571-021-01105-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 05/19/2021] [Indexed: 02/07/2023]
Abstract
Addiction is a chronic and potentially deadly disease considered a global health problem. Nevertheless, there is still no ideal treatment for its management. The alterations in the reward system are the most known pathophysiological mechanisms. Dopamine is the pivotal neurotransmitter involved in neuronal drug reward mechanisms and its neuronal mechanisms have been intensely investigated in recent years. However, neuroglial interactions and their relation to drug addiction development and maintenance of drug addiction have been understudied. Many reports have found that most neuroglial cells express dopamine receptors and that dopamine activity may induce neuroimmunomodulatory effects. Furthermore, current research has also shown that pro- and anti-inflammatory molecules modulate dopaminergic neuron activity. Thus, studying the immune mechanisms of dopamine associated with drug abuse is vital in researching new pathophysiological mechanisms and new therapeutic targets for addiction management.
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Affiliation(s)
- Ariadna Jiménez-González
- Laboratorio de Biomembranas, Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Claudia Gómez-Acevedo
- Laboratorio de Biomembranas, Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Abraham Ochoa-Aguilar
- Plan de Estudios Combinados en Medicina, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Anahí Chavarría
- Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico.
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13
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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: 39] [Impact Index Per Article: 13.0] [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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14
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Wu R, Li JX. Toll-Like Receptor 4 Signaling and Drug Addiction. Front Pharmacol 2020; 11:603445. [PMID: 33424612 PMCID: PMC7793839 DOI: 10.3389/fphar.2020.603445] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 10/22/2020] [Indexed: 12/22/2022] Open
Abstract
The emphasis of neuronal alterations and adaptations have long been the main focus of the studies of the mechanistic underpinnings of drug addiction. Recent studies have begun to appreciate the role of innate immune system, especially toll-like receptor 4 (TLR4) signaling in drug reward-associated behaviors and physiology. Drugs like opioids, alcohol and psychostimulants activate TLR4 signaling and subsequently induce proinflammatory responses, which in turn contributes to the development of drug addiction. Inhibition of TLR4 or its downstream effectors attenuated the reinforcing effects of opioids, alcohol and psychostimulants, and this effect is also involved in the withdrawal and relapse-like behaviors of different drug classes. However, conflicting results also argue that TLR4-related immune response may play a minimal part in drug addiction. This review discussed the preclinical evidence that whether TLR4 signaling is involved in multiple drug classes action and the possible mechanisms underlying this effect. Moreover, clinical studies which examined the potential efficacy of immune-base pharmacotherapies in treating drug addiction are also discussed.
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Affiliation(s)
- Ruyan Wu
- School of Medicine, Yangzhou University, Yangzhou, China.,Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, NY, United States
| | - Jun-Xu Li
- Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, NY, United States
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15
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Toll-like receptors in Alzheimer's disease. J Neuroimmunol 2020; 348:577362. [DOI: 10.1016/j.jneuroim.2020.577362] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/04/2020] [Accepted: 08/15/2020] [Indexed: 02/07/2023]
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16
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Yohimbine Ameliorates Temporomandibular Joint Chondrocyte Inflammation with Suppression of NF-κB Pathway. Inflammation 2020; 44:80-90. [PMID: 32789555 DOI: 10.1007/s10753-020-01310-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Local joint inflammation plays an important role in the pathogenesis of temporomandibular joint (TMJ) osteoarthrosis (TMJOA). Yohimbine, an alpha-2 adrenergic receptor antagonist, possesses anti-inflammatory properties; however, the ability of Yohimbine to protect against TMJOA-associated chondrocyte inflammation remains unclear. We conducted in vitro and in vivo analyses to investigate whether Yohimbine could ameliorate TMJOA-induced chondrocyte inflammation and to elucidate the mechanisms involved. Chondrocytes of TMJOA mice were stimulated with interleukin (IL)-1β or noradrenaline (NE), and the resulting production of inflammation-related factors was evaluated in the presence or absence of Yohimbine. Furthermore, two TMJOA mouse models were treated with Yohimbine and the therapeutic effect was quantified. NE (10-6 M) triggered inflammatory cytokine secretion by TMJ chondrocytes, and Yohimbine suppressed IL-1β- or NE-induced IL-6 upregulation in TMJ chondrocytes with the nuclear factor (NF)-κB pathway inhibition. Yohimbine also ameliorated cartilage destruction in the TMJOA models. Interestingly, αmpT, a tyrosine hydroxylase inhibitor, reversed the effects of Yohimbine by activating the NF-κB pathway. Collectively, these findings show that Yohimbine ameliorated TMJ chondrocyte inflammation and the suppression of NF-κB pathway contributes to this effect.
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17
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Sex-specific effects of developmental exposure to polychlorinated biphenyls on neuroimmune and dopaminergic endpoints in adolescent rats. Neurotoxicol Teratol 2020; 79:106880. [PMID: 32259577 DOI: 10.1016/j.ntt.2020.106880] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 03/17/2020] [Accepted: 03/24/2020] [Indexed: 12/22/2022]
Abstract
Exposure to environmental contaminants early in life can have long lasting consequences for physiological function. Polychlorinated biphenyls (PCBs) are a group of ubiquitous contaminants that perturb endocrine signaling and have been associated with altered immune function in children. In this study, we examined the effects of developmental exposure to PCBs on neuroimmune responses to an inflammatory challenge during adolescence. Sprague Dawley rat dams were exposed to a PCB mixture (Aroclor 1242, 1248, 1254, 1:1:1, 20 μg/kg/day) or oil control throughout pregnancy, and adolescent male and female offspring were injected with lipopolysaccharide (LPS, 50 μg/kg, ip) or saline control prior to euthanasia. Gene expression profiling was conducted in the hypothalamus, prefrontal cortex, striatum, and midbrain. In the hypothalamus, PCBs increased expression of genes involved in neuroimmune function, including those within the nuclear factor kappa b (NF-κB) complex, independent of LPS challenge. PCB exposure also increased expression of receptors for dopamine, serotonin, and estrogen in this region. In contrast, in the prefrontal cortex, PCB exposure blunted or induced irregular neuroimmune gene expression responses to LPS challenge. Moreover, neither PCB nor LPS exposure altered expression of neurotransmitter receptors throughout the mesocorticolimbic circuit. Almost all effects were present in males but not females, in agreement with the idea that male neuroimmune cells are more sensitive to perturbation and emphasizing the importance of studying both male and female subjects. Given that altered neuroimmune signaling has been implicated in mental health and substance abuse disorders that often begin during adolescence, these results highlight neuroimmune processes as another mechanism by which early life PCBs can alter brain function later in life.
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18
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Wang Y, Jiang W, Xia B, Zhang M, Wang Y. MicroRNA-146a attenuates the development of morphine analgesic tolerance in a rat model. Neurol Res 2020; 42:415-421. [PMID: 32131713 DOI: 10.1080/01616412.2020.1735818] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Ying Wang
- Department of Anesthesiology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Wei Jiang
- Department of Anesthesiology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Bin Xia
- Department of Anesthesiology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Mengyuan Zhang
- Department of Anesthesiology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Yan Wang
- Department of Anesthesiology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, China
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19
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Leitner GR, Wenzel TJ, Marshall N, Gates EJ, Klegeris A. Targeting toll-like receptor 4 to modulate neuroinflammation in central nervous system disorders. Expert Opin Ther Targets 2019; 23:865-882. [PMID: 31580163 DOI: 10.1080/14728222.2019.1676416] [Citation(s) in RCA: 130] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Introduction: Adverse immune activation contributes to many central nervous system (CNS) disorders. All main CNS cell types express toll-like receptor 4 (TLR 4). This receptor is critical for a myriad of immune functions such as cytokine secretion and phagocytic activity of microglia; however, imbalances in TLR 4 activation can contribute to the progression of neurodegenerative diseases. Areas covered: We considered available evidence implicating TLR 4 activation in the following CNS pathologies: Alzheimer's disease, Parkinson's disease, ischemic stroke, traumatic brain injury, multiple sclerosis, multiple systems atrophy, and Huntington's disease. We reviewed studies reporting effects of TLR 4-specific antagonists and agonists in models of peripheral and CNS diseases from the perspective of possible future use of TLR 4 ligands in CNS disorders. Expert opinion: TLR 4-specific antagonists could suppress neuroinflammation by reducing overproduction of inflammatory mediators; however, they may interfere with protein clearance mechanisms and myelination. Agonists that specifically activate myeloid differentiation primary-response protein 88 (MyD88)-independent pathway of TLR 4 signaling could facilitate beneficial glial phagocytic activity with limited activity as inducers of proinflammatory mediators. Deciphering the disease stage-specific involvement of TLR 4 in CNS pathologies is crucial for the future clinical development of TLR 4 agonists and antagonists.
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Affiliation(s)
- Gunnar R Leitner
- Department of Biology, University of British Columbia Okanagan Campus , Kelowna , British Columbia , Canada
| | - Tyler J Wenzel
- Department of Biology, University of British Columbia Okanagan Campus , Kelowna , British Columbia , Canada
| | - Nick Marshall
- Department of Biology, University of British Columbia Okanagan Campus , Kelowna , British Columbia , Canada
| | - Ellen J Gates
- Department of Biology, University of British Columbia Okanagan Campus , Kelowna , British Columbia , Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus , Kelowna , British Columbia , Canada
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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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Arige V, Agarwal A, Khan AA, Kalyani A, Natarajan B, Gupta V, Reddy SS, Barthwal MK, Mahapatra NR. Regulation of Monoamine Oxidase B Gene Expression: Key Roles for Transcription Factors Sp1, Egr1 and CREB, and microRNAs miR-300 and miR-1224. J Mol Biol 2019; 431:1127-1147. [PMID: 30738894 DOI: 10.1016/j.jmb.2019.01.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/18/2019] [Accepted: 01/29/2019] [Indexed: 11/15/2022]
Abstract
Monoamine oxidase B (MAO-B), a flavoenzyme located in the outer mitochondrial membrane, is involved in the catabolism of monoamines. Altered levels of MAO-B are associated with cardiovascular/neuronal diseases. However, molecular mechanisms of MAO-B gene regulation are partially understood. We undertook a systematic analysis of the MAO-B gene to identify the key transcriptional/post-transcriptional regulatory molecules. Expression of MAO-B promoter-reporter constructs in cultured cells identified the -144/+25-bp domain as the core promoter region. Stringent in silico analysis of this core promoter predicted binding sites for several transcription factors. Over-expression/down-regulation of transcription factors Sp1/Egr1/CREB increased/decreased the MAO-B promoter-reporter activity and endogenous MAO-B protein level. Electrophoretic mobility shift assays and ChIP assays provided evidence for interactions of Sp1/Egr1/CREB with the MAO-B promoter. MAOB transcript level also positively correlated with the transcript level of Sp1/Egr1/CREB in various human tissue samples. Computational predictions using multiple algorithms coupled with systematic functional analysis revealed direct interactions of the microRNAs miR-1224 and miR-300 with MAO-B 3'-UTR. Dopamine dose-dependently enhanced MAO-B transcript and protein levels via increased binding of CREB to MAO-B promoter and reduced miR-1224/miR-300 levels. 8-Bromo-cAMP and forskolin augmented MAO-B expression, whereas inhibition of PKA diminished the gene expression suggesting involvement of cAMP-PKA axis. Interestingly, Sp1/Egr1/CREB/miR-1224 levels correlate with MAO-B expression in rodent models of hypertension/MPTP-induced neurodegeneration, indicating their roles in governing MAO-B gene expression in these disease states. Taken together, this study elucidates the previously unknown roles of the transcription factors Sp1/Egr1/CREB and microRNAs miR-1224/miR-300 in regulating MAO-B gene expression under basal/disease states involving dysregulated catecholamine levels.
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Affiliation(s)
- Vikas Arige
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | - Anshu Agarwal
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | - Abrar A Khan
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | - Ananthamohan Kalyani
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | - Bhargavi Natarajan
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | - Vinayak Gupta
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | - S Santosh Reddy
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow 226031, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
| | - Manoj K Barthwal
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow 226031, India
| | - Nitish R Mahapatra
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India.
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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: 67] [Impact Index Per Article: 13.4] [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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Linker KE, Cross SJ, Leslie FM. Glial mechanisms underlying substance use disorders. Eur J Neurosci 2018; 50:2574-2589. [PMID: 30240518 DOI: 10.1111/ejn.14163] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 08/23/2018] [Accepted: 08/28/2018] [Indexed: 12/28/2022]
Abstract
Addiction is a devastating disorder that produces persistent maladaptive changes to the central nervous system, including glial cells. Although there is an extensive body of literature examining the neuronal mechanisms of substance use disorders, effective therapies remain elusive. Glia, particularly microglia and astrocytes, have an emerging and meaningful role in a variety of processes beyond inflammation and immune surveillance, and may represent a promising therapeutic target. Indeed, glia actively modulate neurotransmission, synaptic connectivity and neural circuit function, and are critically poised to contribute to addictive-like brain states and behaviors. In this review, we argue that glia influence the cellular, molecular, and synaptic changes that occur in neurons following drug exposure, and that this cellular relationship is critically modified following drug exposure. We discuss direct actions of abused drugs on glial function through immune receptors, such as Toll-like receptor 4, as well as other mechanisms. We highlight how drugs of abuse affect glia-neural communication, and the profound effects that glial-derived factors have on neuronal excitability, structure, and function. Recent research demonstrates that glia have brain region-specific functions, and glia in different brain regions have distinct contributions to drug-associated behaviors. We will also evaluate the evidence demonstrating that glial activation is essential for drug reward and drug-induced dopamine release, and highlight clinical evidence showing that glial mechanisms contribute to drug abuse liability. In this review, we synthesize the extensive evidence that glia have a unique, pivotal, and underappreciated role in the development and maintenance of addiction.
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Affiliation(s)
- K E Linker
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - S J Cross
- Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA, USA
| | - F M Leslie
- Department of Pharmacology, University of California Irvine, Irvine, CA, USA
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Persistent Stress-Induced Neuroplastic Changes in the Locus Coeruleus/Norepinephrine System. Neural Plast 2018; 2018:1892570. [PMID: 30008741 PMCID: PMC6020552 DOI: 10.1155/2018/1892570] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 05/09/2018] [Accepted: 05/27/2018] [Indexed: 11/25/2022] Open
Abstract
Neural plasticity plays a critical role in mediating short- and long-term brain responses to environmental stimuli. A major effector of plasticity throughout many regions of the brain is stress. Activation of the locus coeruleus (LC) is a critical step in mediating the neuroendocrine and behavioral limbs of the stress response. During stressor exposure, activation of the hypothalamic-pituitary-adrenal axis promotes release of corticotropin-releasing factor in LC, where its signaling promotes a number of physiological and cellular changes. While the acute effects of stress on LC physiology have been described, its long-term effects are less clear. This review will describe how stress changes LC neuronal physiology, function, and morphology from a genetic, cellular, and neuronal circuitry/transmission perspective. Specifically, we describe morphological changes of LC neurons in response to stressful stimuli and signal transduction pathways underlying them. Also, we will review changes in excitatory glutamatergic synaptic transmission in LC neurons and possible stress-induced modifications of AMPA receptors. This review will also address stress-related behavioral adaptations and specific noradrenergic receptors responsible for them. Finally, we summarize the results of several human studies which suggest a link between stress, altered LC function, and pathogenesis of posttraumatic stress disorder.
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25
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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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26
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Balan I, Warnock KT, Puche A, Gondre-Lewis MC, Aurelian L. Innately activated TLR4 signal in the nucleus accumbens is sustained by CRF amplification loop and regulates impulsivity. Brain Behav Immun 2018; 69:139-153. [PMID: 29146239 PMCID: PMC5857415 DOI: 10.1016/j.bbi.2017.11.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 10/31/2017] [Accepted: 11/12/2017] [Indexed: 12/25/2022] Open
Abstract
Cognitive impulsivity is a heritable trait believed to represent the behavior that defines the volition to initiate alcohol drinking. We have previously shown that a neuronal Toll-like receptor 4 (TLR4) signal located in the central amygdala (CeA) and ventral tegmental area (VTA) controls the initiation of binge drinking in alcohol-preferring P rats, and TLR4 expression is upregulated by alcohol-induced corticotropin-releasing factor (CRF) at these sites. However, the function of the TLR4 signal in the nucleus accumbens shell (NAc-shell), a site implicated in the control of reward, drug-seeking behavior and impulsivity and the contribution of other signal-associated genes, are still poorly understood. Here we report that P rats have an innately activated TLR4 signal in NAc-shell neurons that co-express the α2 GABAA receptor subunit and CRF prior to alcohol exposure. This signal is not present in non-alcohol drinking NP rats. The TLR4 signal is sustained by a CRF amplification loop, which includes TLR4-mediated CRF upregulation through PKA/CREB activation and CRF-mediated TLR4 upregulation through the CRF type 1 receptor (CRFR1) and the MAPK/ERK pathway. NAc-shell Infusion of a neurotropic, non-replicating herpes simplex virus vector for TLR4-specific small interfering RNA (pHSVsiTLR4) inhibits TLR4 expression and cognitive impulsivity, implicating the CRF-amplified TLR4 signal in impulsivity regulation.
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Affiliation(s)
- Irina Balan
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Kaitlin T Warnock
- Neuropsychopharmacology Laboratory, Department of Psychiatry and Behavioral Sciences, Howard University College of Medicine, Washington, DC, USA
| | - Adam Puche
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Marjorie C Gondre-Lewis
- Department of Anatomy, Laboratory for Neurodevelopment, Howard University College of Medicine, Washington, DC, USA
| | - Laure Aurelian
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, USA.
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27
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Jacobsen JHW, Buisman-Pijlman FTA, Mustafa S, Rice KC, Hutchinson MR. The efficacy of (+)-Naltrexone on alcohol preference and seeking behaviour is dependent on light-cycle. Brain Behav Immun 2018; 67:181-193. [PMID: 28864261 PMCID: PMC7387101 DOI: 10.1016/j.bbi.2017.08.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 08/18/2017] [Accepted: 08/28/2017] [Indexed: 02/06/2023] Open
Abstract
Circadian rhythm affects drug-induced reward behaviour and the innate immune system. Peaks in reward-associated behaviour and immune responses typically occur during the active (dark) phase of rodents. While the role of the immune system, specifically, Toll-like receptor 4 (TLR4, an innate immune receptor) in drug-induced reward is becoming increasingly appreciated, it is unclear whether its effects vary according to light-cycle. Therefore, the aim of this study was to characterise the effects of the phase of the light-cycle and the state of the innate immune system on alcohol reward behaviour and subsequently determine whether the efficacy of targeting the immune component of drug reward depends upon the light-cycle. This study demonstrates that mice exhibit greater alcohol-induced conditioned place preference and alcohol two-bottle choice preference during the dark cycle. This effect overlapped with elevations in reward-, thirst- and immune-related genes. Administration of (+)-Naltrexone, a TLR4 antagonist, reduced immune-related gene mRNA expression and alcohol preference with its effects most pronounced during the dark cycle. However, (+)-Naltrexone, like other TLR4 antagonists exhibited off-target side effects, with a significant reduction in overall saccharin intake - an effect likely attributable to a reduction in tyrosine hydroxylase (Th) mRNA expression levels. Collectively, the study highlights a link between a time-of-day dependent influence of TLR4 on natural and alcohol reward-like behaviour in mice.
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Affiliation(s)
- Jonathan Henry W Jacobsen
- Discipline of Pharmacology, Adelaide Medical School, University of Adelaide, South Australia, Australia
| | - Femke T A Buisman-Pijlman
- Discipline of Pharmacology, Adelaide Medical School, University of Adelaide, South Australia, Australia
| | - Sanam Mustafa
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, South Australia, Australia; ARC Centre of Excellence for Nanoscale Biophotonics, University of Adelaide, South Australia, Australia
| | - Kenner C Rice
- Drug Design and Synthesis Section, NIDA, Rockville, MD, USA
| | - Mark R Hutchinson
- Discipline of Physiology, Adelaide Medical School, University of Adelaide, South Australia, Australia; ARC Centre of Excellence for Nanoscale Biophotonics, University of Adelaide, South Australia, Australia.
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Antagonising TLR4-TRIF signalling before or after a low-dose alcohol binge during adolescence prevents alcohol drinking but not seeking behaviour in adulthood. Neuropharmacology 2017; 128:460-473. [PMID: 28947376 DOI: 10.1016/j.neuropharm.2017.09.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Revised: 08/18/2017] [Accepted: 09/19/2017] [Indexed: 12/20/2022]
Abstract
Adolescents frequently engage in risky behaviours such as binge drinking. Binge drinking, in turn, perturbs neurodevelopment reinforcing reward seeking behaviour in adulthood. Current animal models are limited in their portrayal of this behaviour and the assessment of neuroimmune involvement (specifically the role of Toll-like receptor 4 (TLR4)). Therefore, the aims of this project were to develop a more relevant animal model of adolescent alcohol exposure and to characterise its effects on TLR4 signalling and alcohol-related behaviours later life. Balb/c mice received a short (P22-P25), low dose alcohol binge during in early adolescence, and underwent tests to investigate anxiety (elevated plus maze), alcohol seeking (conditioned place preference) and binge drinking behaviour (drinking in the dark) in adulthood. Four doses of alcohol during adolescence increased alcohol-induced conditioned place preference and alcohol intake in adulthood. However, this model did not affect basal elevated plus maze performance. Subsequent analysis of nucleus accumbal mRNA, revealed increased expression of TLR4-related mRNAs in mice who received alcohol during adolescence. To further elucidate the role of TLR4, (+)-Naltrexone, a biased TLR4 antagonist was administered 30 min before or after the adolescent binge paradigm. When tested in adulthood, (+)-Naltrexone treated mice exhibited reduced alcohol intake however, alcohol seeking and anxiety behaviour was unaltered. This study highlights that even a small amount of alcohol, when given during a critical neurodevelopmental period, can potentiate alcohol-related behaviours and TLR4 activation later in life. Interestingly, attenuation of TLR4 before or after adolescent alcohol exposure reduced only binge alcohol intake in adulthood.
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McCarthy GM, Bridges CR, Blednov YA, Harris RA. CNS cell-type localization and LPS response of TLR signaling pathways. F1000Res 2017; 6:1144. [PMID: 29043065 PMCID: PMC5621151 DOI: 10.12688/f1000research.12036.1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/17/2017] [Indexed: 12/15/2022] Open
Abstract
Background: Innate immune signaling in the brain has emerged as a contributor to many central nervous system (CNS) pathologies, including mood disorders, neurodegenerative disorders, neurodevelopmental disorders, and addiction. Toll-like receptors (TLRs), a key component of the innate immune response, are particularly implicated in neuroimmune dysfunction. However, most of our understanding about TLR signaling comes from the peripheral immune response, and it is becoming clear that the CNS immune response is unique. One controversial aspect of neuroimmune signaling is which CNS cell types are involved. While microglia are the CNS cell-type derived from a myeloid lineage, studies suggest that other glial cell types and even neurons express TLRs, although this idea is controversial. Furthermore, recent work suggests a discrepancy between RNA and protein expression within the CNS. Methods: To elucidate the CNS cell-type localization of TLRs and their downstream signaling molecules, we isolated microglia and astrocytes from the brain of adult mice treated with saline or the TLR4 ligand lipopolysaccharide (LPS). Glial mRNA and protein expression was compared to a cellular-admixture to determine cell-type enrichment. Results: Enrichment analysis revealed that most of the TLR pathway genes are localized in microglia and changed in microglia following immune challenge. However, expression of
Tlr3 was enriched in astrocytes, where it increased in response to LPS. Furthermore, attempts to determine protein cell-type localization revealed that many antibodies are non-specific and that antibody differences are contributing to conflicting localization results. Conclusions: Together these results highlight the cell types that should be looked at when studying TLR signaling gene expression and suggest that non-antibody approaches need to be used to accurately evaluate protein expression.
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Affiliation(s)
- Gizelle M McCarthy
- Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX, 78712, USA.,Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, TX, 78712, USA
| | - Courtney R Bridges
- Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, TX, 78712, USA
| | - Yuri A Blednov
- Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, TX, 78712, USA
| | - R Adron Harris
- Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX, 78712, USA.,Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, TX, 78712, USA.,Insitute for Neuroscience, University of Texas at Austin, Austin, TX, 78712, USA
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Camandola S, Mattson MP. Toll-like receptor 4 mediates fat, sugar, and umami taste preference and food intake and body weight regulation. Obesity (Silver Spring) 2017; 25:1237-1245. [PMID: 28500692 PMCID: PMC5487280 DOI: 10.1002/oby.21871] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 03/08/2017] [Accepted: 04/06/2017] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Immune and inflammatory pathways play important roles in the pathogenesis of metabolic disorders. This study investigated the role of toll-like receptor 4 (TLR4) in orosensory detection of dietary lipids and sugars. METHODS Taste preferences of TLR4 knockout (KO) and wild-type (WT) male mice under a standard and a high-fat, high-sugar diet were assessed with two-bottle tests. Gene expression of taste signaling molecules was analyzed in the tongue epithelium. The role of TLR4 in food intake and weight gain was investigated in TLR4 KO and WT mice fed a high-fat and high-sugar diet for 12 weeks. RESULTS Compared to WT mice, TLR4 KO mice showed reduced preference for lipids, sugars, and umami in a two-bottle preference test. The altered taste perception was associated with decreased levels of key taste regulatory molecules in the tongue epithelium. TLR4 KO mice on a high-fat and high-sugar diet consumed less food and drink, resulting in diminished weight gain. CONCLUSIONS TLR4 signaling promotes ingestion of sugar and fat by a mechanism involving increased preference for such obesogenic foods.
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Affiliation(s)
- Simonetta Camandola
- Laboratory of Neurosciences, National Institute on Aging, Intramural Research Program, Baltimore, MD, USA
| | - Mark P. Mattson
- Laboratory of Neurosciences, National Institute on Aging, Intramural Research Program, Baltimore, MD, USA
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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