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Siemsen BM, Denton AR, Parrila-Carrero J, Hooker KN, Carpenter EA, Prescot ME, Brock AG, Westphal AM, Leath MN, McFaddin JA, Jhou TC, McGinty JF, Scofield MD. Heroin Self-Administration and Extinction Increase Prelimbic Cortical Astrocyte-Synapse Proximity and Alter Dendritic Spine Morphometrics That Are Reversed by N-Acetylcysteine. Cells 2023; 12:1812. [PMID: 37508477 PMCID: PMC10378353 DOI: 10.3390/cells12141812] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 05/09/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023] Open
Abstract
Clinical and preclinical studies indicate that adaptations in corticostriatal neurotransmission significantly contribute to heroin relapse vulnerability. In animal models, heroin self-administration and extinction produce cellular adaptations in both neurons and astrocytes within the nucleus accumbens (NA) core that are required for cue-induced heroin seeking. Specifically, decreased glutamate clearance and reduced association of perisynaptic astrocytic processes with NAcore synapses allow glutamate release from prelimbic (PrL) cortical terminals to engage synaptic and structural plasticity in NAcore medium spiny neurons. Normalizing astrocyte glutamate homeostasis with drugs like the antioxidant N-acetylcysteine (NAC) prevents cue-induced heroin seeking. Surprisingly, little is known about heroin-induced alterations in astrocytes or pyramidal neurons projecting to the NAcore in the PrL cortex (PrL-NAcore). Here, we observe functional adaptations in the PrL cortical astrocyte following heroin self-administration (SA) and extinction as measured by the electrophysiologically evoked plasmalemmal glutamate transporter 1 (GLT-1)-dependent current. We likewise observed the increased complexity of the glial fibrillary acidic protein (GFAP) cytoskeletal arbor and increased association of the astrocytic plasma membrane with synaptic markers following heroin SA and extinction training in the PrL cortex. Repeated treatment with NAC during extinction reversed both the enhanced astrocytic complexity and synaptic association. In PrL-NAcore neurons, heroin SA and extinction decreased the apical tuft dendritic spine density and enlarged dendritic spine head diameter in male Sprague-Dawley rats. Repeated NAC treatment during extinction prevented decreases in spine density but not dendritic spine head expansion. Moreover, heroin SA and extinction increased the co-registry of the GluA1 subunit of AMPA receptors in both the dendrite shaft and spine heads of PrL-NAcore neurons. Interestingly, the accumulation of GluA1 immunoreactivity in spine heads was further potentiated by NAC treatment during extinction. Finally, we show that the NAC treatment and elimination of thrombospondin 2 (TSP-2) block cue-induced heroin relapse. Taken together, our data reveal circuit-level adaptations in cortical dendritic spine morphology potentially linked to heroin-induced alterations in astrocyte complexity and association at the synapses. Additionally, these data demonstrate that NAC reverses PrL cortical heroin SA-and-extinction-induced adaptations in both astrocytes and corticostriatal neurons.
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Affiliation(s)
- Benjamin M. Siemsen
- Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Adam R. Denton
- Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC 29425, USA
| | | | - Kaylee N. Hooker
- Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Eilish A. Carpenter
- Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Meagan E. Prescot
- Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Ashley G. Brock
- Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Annaka M. Westphal
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Mary-Nan Leath
- Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
| | - John A. McFaddin
- Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Thomas C. Jhou
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Jacqueline F. McGinty
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Michael D. Scofield
- Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC 29425, USA
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2
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Randall CA, Sun D, Randall PA. Differential Effects of Nicotine, Alcohol, and Coexposure on Neuroimmune-Related Protein and Gene Expression in Corticolimbic Brain Regions of Rats. ACS Chem Neurosci 2023; 14:628-644. [PMID: 36705334 DOI: 10.1021/acschemneuro.2c00413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Nicotine and alcohol co-use is extremely common and their use constitutes two of the most common causes of preventable death, yet the underlying biological mechanisms are largely understudied. Activation of neuroimmune toll-like receptors (TLRs) promotes the induction of proinflammatory cascades and increases alcohol intake in rodents, which further promotes TLRs in the brain; nicotine may decrease central proinflammatory signaling. The current studies sought to determine the effects of nicotine ± alcohol (alone or in combination) on circulating blood plasma and TLR protein/gene expression in addiction-associated corticolimbic brain regions, including the prefrontal cortex-prelimbic (mPFC-PL) and nucleus accumbens core (AcbC). Adult rats were treated with alcohol (0 or 2 g/kg, IG) and exposed to nicotine vapor (0 or 30 mg/mL solution) daily for 2, 14, or 28 days. Plasma studies indicated no effects of independent exposure or coexposure in males. Coexposure decreased plasma nicotine levels versus nicotine-only treated females, yet alcohol and cotinine concentrations were unchanged. By 28 days, the anti-inflammatory cytokine IL-13 was decreased in alcohol-only females. Divergent changes in TLR3 (but not TLR4) protein occurred for independent-drug exposed males (but not coexposure), with reductions in the mPFC-PL after 14 days and increases in the AcbC by 28 days. Gene expression following chronic coexposure suggests nicotine may regionally counteract alcohol-induced inflammation, including increased AcbC-TLR3/4/7 and several downstream markers in females and increased mPFC-PL-TLR3 and -STAT3 (but not IRF3) evident in males with exposure to either drug alone. These findings give further insight into the role of sex and the neuroimmune system in independent exposure and coexposure to nicotine ± alcohol.
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Affiliation(s)
- Christie A Randall
- Department of Anesthesiology and Perioperative Medicine, College of Medicine, Pennsylvania State University, 500 University Drive, Hershey, Pennsylvania 17033, United States
| | - Dongxiao Sun
- Department of Pharmacology, College of Medicine, Pennsylvania State University, Hershey, Pennsylvania 17033 United States
| | - Patrick A Randall
- Department of Anesthesiology and Perioperative Medicine, College of Medicine, Pennsylvania State University, 500 University Drive, Hershey, Pennsylvania 17033, United States.,Department of Pharmacology, College of Medicine, Pennsylvania State University, Hershey, Pennsylvania 17033 United States
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3
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Mechanistic Effects and Use of N-acetylcysteine in Substance Use Disorders. Curr Behav Neurosci Rep 2022. [DOI: 10.1007/s40473-022-00250-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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4
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Maher EE, Kipp ZA, Leyrer-Jackson JM, Khatri S, Bondy E, Martinez GJ, Beckmann JS, Hinds TD, Bimonte-Nelson HA, Gipson CD. Ovarian Hormones Regulate Nicotine Consumption and Accumbens Glutamatergic Plasticity in Female Rats. eNeuro 2022; 9:ENEURO.0286-21.2022. [PMID: 35697512 PMCID: PMC9239849 DOI: 10.1523/eneuro.0286-21.2022] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 05/26/2022] [Accepted: 06/06/2022] [Indexed: 11/21/2022] Open
Abstract
Women report greater cigarette cravings during the menstrual cycle phase with higher circulating levels of 17β-estradiol (E2), which is metabolized to estrone (E1). Both E2 and E1 bind to estrogen receptors (ERs), which have been highly studied in the breast, uterus, and ovary. Recent studies have found that ERs are also located on GABAergic medium spiny neurons (MSNs) within the nucleus accumbens core (NAcore). Glutamatergic plasticity in NAcore MSNs is altered following nicotine use; however, it is unknown whether estrogens impact this neurobiological consequence. To test the effect of estrogen on nicotine use, we ovariectomized (OVX) female rats that then underwent nicotine self-administration acquisition and compared them to ovary-intact (sham) rats. The OVX animals then received either sesame oil (vehicle), E2, or E1+E2 supplementation for 4 or 20 d before nicotine sessions. While both ovary-intact and OVX females readily discriminated levers, OVX females consumed less nicotine than sham females. Further, neither E2 nor E1+E2 increased nicotine consumption back to sham levels following OVX, regardless of the duration of the treatment. OVX also rendered NAcore MSNs in a potentiated state following nicotine self-administration, which was reversed by 4 d of systemic E2 treatment. Finally, we found that E2 and E1+E2 increased ERα mRNA in the NAcore, but nicotine suppressed this regardless of hormone treatment. Together, these results show that estrogens regulate nicotine neurobiology, but additional factors may be required to restore nicotine consumption to ovary-intact levels.
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Affiliation(s)
- Erin E Maher
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, 40536
| | - Zachary A Kipp
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, 40536
| | | | - Shailesh Khatri
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, 40536
| | - Emma Bondy
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, 40536
| | - Genesee J Martinez
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, 40536
| | - Joshua S Beckmann
- Department of Psychology, University of Kentucky, Lexington, KY, 40506
| | - Terry D Hinds
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, 40536
- Barnstable Brown Diabetes Center, University of Kentucky College of Medicine, Lexington, KY, 40536
- Markey Cancer Center, University of Kentucky, Lexington, KY, 40536
| | - Heather A Bimonte-Nelson
- Department of Psychology, Arizona State University, Tempe, AZ, 85287
- Arizona Alzheimer's Consortium, Phoenix, AZ 85014
| | - Cassandra D Gipson
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, KY, 40536
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Nall RW, Beloate LN, Meyerink ME, Penaloza T, Doolittle J, Froeliger B, Kalivas PW, Garcia-Keller C. Assessing combined effects of varenicline and N-acetylcysteine on reducing nicotine seeking in rats. Addict Biol 2022; 27:e13151. [PMID: 35229943 PMCID: PMC10777539 DOI: 10.1111/adb.13151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 12/22/2021] [Accepted: 01/14/2022] [Indexed: 11/27/2022]
Abstract
Nicotine addiction is a chronic relapsing brain disorder, and cigarette smoking is the leading cause of preventable death in the United States. Currently, the most effective pharmacotherapy for smoking cessation is Varenicline (VRN), which reduces both positive and negative reinforcement by nicotine. Clinically, VRN attenuates withdrawal symptoms and promotes abstinence, but >50% of smokers relapse within 3 months following a quit attempt. This may indicate that VRN fails to ameliorate components of nicotine-induced neuroplasticity that promote relapse vulnerability. Animal models reveal that glutamate dysregulation in the nucleus accumbens is associated with nicotine relapse. N-acetylcysteine (NAC) normalizes glutamate transmission and prolongs cocaine abstinence. Thus, combining VRN and NAC may promote and maintain, respectively, nicotine abstinence. In rats, we found that VRN effectively reduced nicotine self-administration and seeking in early abstinence, but not seeking later in abstinence. In contrast, NAC reduced seeking only later in abstinence. Because VRN and NAC are sometimes associated with mild adverse effects, we also evaluated a sequential approach combining subthreshold doses of VRN during self-administration and early abstinence with subthreshold doses of NAC during late abstinence. As expected, subthreshold VRN did not reduce nicotine intake. However, subthreshold VRN and NAC reduced seeking in late abstinence, suggesting a combined effect. Overall, our results suggest that combining subthreshold VRN and NAC is a viable and drug-specific approach to promote abstinence and reduce relapse while minimizing adverse effects. Our data also suggest that different components and time points in addiction engage the different neurocircuits targeted by VRN and NAC.
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Affiliation(s)
- Rusty W. Nall
- Department of Neuroscience, Medical University of South Carolina, 173 Ashley Ave, Charleston, SC 29425
- Department of Psychology, Jacksonville State University, 700 Pelham Rd. N., Jacksonville, AL, 36265
| | - Lauren N. Beloate
- Department of Neuroscience, Medical University of South Carolina, 173 Ashley Ave, Charleston, SC 29425
- Department of Biomedical Engineering, The Pennsylvania State University, 122 Chemical and Biomedical Engineering Building, University Park, PA 16802
| | - Michael E. Meyerink
- Department of Neuroscience, Medical University of South Carolina, 173 Ashley Ave, Charleston, SC 29425
| | - Tiffany Penaloza
- Department of Neuroscience, Medical University of South Carolina, 173 Ashley Ave, Charleston, SC 29425
| | - Jade Doolittle
- Department of Neuroscience, Medical University of South Carolina, 173 Ashley Ave, Charleston, SC 29425
| | - Brett Froeliger
- Department of Neuroscience, Medical University of South Carolina, 173 Ashley Ave, Charleston, SC 29425
- Department of Psychiatry, Department of Psychological Sciences, University of Missouri-Columbia, 1 Hospital Dr, Columbia, MO 65201
| | - Peter W. Kalivas
- Department of Neuroscience, Medical University of South Carolina, 173 Ashley Ave, Charleston, SC 29425
| | - Constanza Garcia-Keller
- Department of Neuroscience, Medical University of South Carolina, 173 Ashley Ave, Charleston, SC 29425
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6
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Leyrer-Jackson JM, Overby PF, Bull A, Marusich JA, Gipson CD. Strain and sex matters: Differences in nicotine self-administration between outbred and recombinase-driver transgenic rat lines. Exp Clin Psychopharmacol 2021; 29:375-384. [PMID: 32297781 PMCID: PMC8375641 DOI: 10.1037/pha0000376] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Preclinical studies of nicotine self-administration provide important value for the field as they are highly rigorous, controlled, can be conducted quickly, and are generalizable to humans. Given the translational value of the nicotine self-administration model, and the relatively new guidelines of the National Institutes of Health to include sex as a biological variable, strain and sex differences in nicotine acquisition were examined here in two outbred rat strains. Sprague-Dawley (SD) and Long-Evans (LE; wildtype and cholinergic acetyltransferase cre-recombinase transgenic) rats of each sex were implanted with indwelling intravenous jugular catheters. Rats were trained to self-administer nicotine (0.02 mg/kg per infusion, paired with contingent light + tone stimuli). Acquisition criteria were set at a minimum active:inactive response ratio of 2:1 and a minimum of 10 infusions per session, both of which had to be met for a minimum of 10 sessions. Across 10 sessions, male SD rats self-administered significantly more nicotine than female SD rats (p < .05), indicating a sex difference in this strain. LE females self-administered more nicotine than SD females indicative of a strain difference between females (p < .05). SD males increased nicotine infusions across sessions compared to LE males and SD females (p < .05). No strain or sex differences were observed in the number of sessions to reach criteria. No differences between wildtype and transgenic LE rats were observed. These results demonstrate sex and strain differences in nicotine self-administration between SD and LE rats and may lend insight into development of other nicotine self-administration models, where sex and strain may impact acquisition. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
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Affiliation(s)
| | - Paula F. Overby
- Department of Psychology, Arizona State University, Tempe, Arizona, USA
| | - Amanda Bull
- Department of Psychology, Arizona State University, Tempe, Arizona, USA
| | - Julie A. Marusich
- Center for Drug Discovery, RTI International, Research Triangle Park, North Carolina, USA
| | - Cassandra D. Gipson
- Department of Family and Community Medicine, University of Kentucky, Lexington Kentucky, USA
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7
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McClure EA, Wahlquist AE, Tomko RL, Baker NL, Carpenter MJ, Bradley ED, Cato PA, Gipson CD, Gray KM. Evaluating N-acetylcysteine for early and end-of-treatment abstinence in adult cigarette smokers. Drug Alcohol Depend 2021; 225:108815. [PMID: 34171822 PMCID: PMC8282766 DOI: 10.1016/j.drugalcdep.2021.108815] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 04/02/2021] [Accepted: 04/10/2021] [Indexed: 01/21/2023]
Abstract
BACKGROUND There is robust preclinical literature and preliminary clinical findings supporting the use of N-Acetylcysteine (NAC) to treat substance use disorders, including tobacco use disorder (TUD). However, randomized controlled trials have yielded mixed results and NAC's efficacy for TUD has not been established. The goals of this study were to assess the efficacy of NAC in promoting early and end-of-treatment abstinence and preventing relapse among adult smokers. METHODS This randomized, double-blinded clinical trial enrolled adult, daily smokers (N = 114; ages 23-64; 51 % female; 65 % White; 29 % Black/African American; 7% Hispanic/Latinx), who were randomized 1:1 to receive NAC (n = 59) or placebo (n = 55) (1200 mg b.i.d.) for eight weeks. Participants received brief cessation counseling and incentives for abstinence during the first three days of the quit attempt. Primary outcomes: (i) carbon monoxide (CO)-confirmed abstinence during the first three days of the quit attempt. SECONDARY OUTCOMES (ii) time to relapse; (iii) biologically confirmed abstinence at Week 8. RESULTS No differences were found between NAC and placebo groups on measures of early abstinence (3-day quit attempt; 11 % for NAC vs. 15 % for placebo; all p > 0.11), time to relapse (p = 0.19), and end-of-treatment abstinence (7% for NAC vs. 11 % for placebo; all p > 0.40]. CONCLUSIONS Results indicate that NAC is a well-tolerated pharmacotherapy but is unlikely to be efficacious as a monotherapy for TUD in adults. Considered in the collective context of other research, NAC may potentially be more useful in a younger population, as a combination pharmacotherapy, or in the presence of more intensive psychosocial treatment.
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Affiliation(s)
- Erin A. McClure
- Medical University of South Carolina, Department of Psychiatry and Behavioral Sciences, 67 President St., MSC 861, Charleston SC, 29425, USA,Hollings Cancer Center, Medical University of South Carolina, 86 Jonathan Lucas St., Charleston SC, 29425, USA,Corresponding Author: Erin A. McClure, Ph.D., Medical University of South Carolina, 67 President St, MSC 861, Charleston, SC 29425, Phone: 843-792-7192,
| | - Amy E. Wahlquist
- East Tennessee State University, Center for Rural Health Research, Department of Biostatistics and Epidemiology, 104 Lamb Hall, Johnson City, TN, 37612, USA
| | - Rachel L. Tomko
- Medical University of South Carolina, Department of Psychiatry and Behavioral Sciences, 67 President St., MSC 861, Charleston SC, 29425, USA
| | - Nathaniel L. Baker
- Medical University of South Carolina, Department of Public Health Sciences, 135 Cannon St., Charleston SC, 29425, USA
| | - Matthew J. Carpenter
- Medical University of South Carolina, Department of Psychiatry and Behavioral Sciences, 67 President St., MSC 861, Charleston SC, 29425, USA,Hollings Cancer Center, Medical University of South Carolina, 86 Jonathan Lucas St., Charleston SC, 29425, USA
| | - Elizabeth D. Bradley
- Medical University of South Carolina, Department of Psychiatry and Behavioral Sciences, 67 President St., MSC 861, Charleston SC, 29425, USA
| | - Patrick A. Cato
- Medical University of South Carolina, Department of Psychiatry and Behavioral Sciences, 67 President St., MSC 861, Charleston SC, 29425, USA
| | - Cassandra D. Gipson
- Department of Family and Community Medicine, University of Kentucky, 2195 Harrodsburg Rd., Lexington KY, 40504, USA
| | - Kevin M. Gray
- Medical University of South Carolina, Department of Psychiatry and Behavioral Sciences, 67 President St., MSC 861, Charleston SC, 29425, USA
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N-acetylcysteine in substance use disorder: a lesson from preclinical and clinical research. Pharmacol Rep 2021; 73:1205-1219. [PMID: 34091880 PMCID: PMC8460563 DOI: 10.1007/s43440-021-00283-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 05/19/2021] [Accepted: 05/19/2021] [Indexed: 12/29/2022]
Abstract
Substance use disorder (SUD) is a chronic brain condition, with compulsive and uncontrollable drug-seeking that leads to long-lasting and harmful consequences. The factors contributing to the development of SUD, as well as its treatment settings, are not fully understood. Alterations in brain glutamate homeostasis in humans and animals implicate a key role of this neurotransmitter in SUD, while the modulation of glutamate transporters has been pointed as a new strategy to diminish the excitatory glutamatergic transmission observed after drugs of abuse. N-acetylcysteine (NAC), known as a safe mucolytic agent, is involved in the regulation of this system and may be taken into account as a novel pharmacotherapy for SUD. In this paper, we summarize the current knowledge on the ability of NAC to reduce drug-seeking behavior induced by psychostimulants, opioids, cannabinoids, nicotine, and alcohol in animals and humans. Preclinical studies showed a beneficial effect in animal models of SUD, while the clinical efficacy of NAC has not been fully established. In summary, NAC will be a small add-on to usual treatment and/or psychotherapy for SUD, however, further studies are required.
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9
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Namba MD, Leyrer-Jackson JM, Nagy EK, Olive MF, Neisewander JL. Neuroimmune Mechanisms as Novel Treatment Targets for Substance Use Disorders and Associated Comorbidities. Front Neurosci 2021; 15:650785. [PMID: 33935636 PMCID: PMC8082184 DOI: 10.3389/fnins.2021.650785] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 03/24/2021] [Indexed: 12/12/2022] Open
Abstract
Recent studies examining the neurobiology of substance abuse have revealed a significant role of neuroimmune signaling as a mechanism through which drugs of abuse induce aberrant changes in synaptic plasticity and contribute to substance abuse-related behaviors. Immune signaling within the brain and the periphery critically regulates homeostasis of the nervous system. Perturbations in immune signaling can induce neuroinflammation or immunosuppression, which dysregulate nervous system function including neural processes associated with substance use disorders (SUDs). In this review, we discuss the literature that demonstrates a role of neuroimmune signaling in regulating learning, memory, and synaptic plasticity, emphasizing specific cytokine signaling within the central nervous system. We then highlight recent preclinical studies, within the last 5 years when possible, that have identified immune mechanisms within the brain and the periphery associated with addiction-related behaviors. Findings thus far underscore the need for future investigations into the clinical potential of immunopharmacology as a novel approach toward treating SUDs. Considering the high prevalence rate of comorbidities among those with SUDs, we also discuss neuroimmune mechanisms of common comorbidities associated with SUDs and highlight potentially novel treatment targets for these comorbid conditions. We argue that immunopharmacology represents a novel frontier in the development of new pharmacotherapies that promote long-term abstinence from drug use and minimize the detrimental impact of SUD comorbidities on patient health and treatment outcomes.
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Affiliation(s)
- Mark D. Namba
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | | | - Erin K. Nagy
- Department of Psychology, Arizona State University, Tempe, AZ, United States
| | - M. Foster Olive
- Department of Psychology, Arizona State University, Tempe, AZ, United States
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10
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Quintanilla ME, Morales P, Ezquer F, Ezquer M, Herrera-Marschitz M, Israel Y. Administration of N-acetylcysteine Plus Acetylsalicylic Acid Markedly Inhibits Nicotine Reinstatement Following Chronic Oral Nicotine Intake in Female Rats. Front Behav Neurosci 2021; 14:617418. [PMID: 33633548 PMCID: PMC7902020 DOI: 10.3389/fnbeh.2020.617418] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 12/31/2020] [Indexed: 12/13/2022] Open
Abstract
Background Nicotine is the major addictive component of cigarette smoke and the prime culprit of the failure to quit smoking. Common elements perpetuating the use of addictive drugs are (i) cues associated with the setting in which drug was used and (ii) relapse/reinstatement mediated by an increased glutamatergic tone (iii) associated with drug-induced neuroinflammation and oxidative stress. Aims The present study assessed the effect of the coadministration of the antioxidant N-acetylcysteine (NAC) plus the anti-inflammatory acetylsalicylic acid (ASA) on oral nicotine reinstatement intake following a post-deprivation re-access in female rats that had chronically and voluntarily consumed a nicotine solution orally. The nicotine-induced oxidative stress and neuroinflammation in the hippocampus and its effects on the glutamate transporters GLT-1 and XCT mRNA levels in prefrontal cortex were also analyzed. Results The oral coadministration of NAC (40 mg/kg/day) and ASA (15 mg/kg/day) inhibited by 85% of the oral nicotine reinstatement intake compared to control (vehicle), showing an additive effect of both drugs. Acetylsalicylic acid and N-acetylcysteine normalized hippocampal oxidative stress and blunted the hippocampal neuroinflammation observed upon oral nicotine reinstatement. Nicotine downregulated GLT-1 and xCT gene expression in the prefrontal cortex, an effect reversed by N-acetylcysteine, while acetylsalicylic acid reversed the nicotine-induced downregulation of GLT-1 gene expression. The inhibitory effect of N-acetylcysteine on chronic nicotine intake was blocked by the administration of sulfasalazine, an inhibitor of the xCT transporter. Conclusion Nicotine reinstatement, following post-deprivation of chronic oral nicotine intake, downregulates the mRNA levels of GLT-1 and xCT transporters, an effect reversed by the coadministration of N-acetylcysteine and acetylsalicylic acid, leading to a marked inhibition of nicotine intake. The combination of these drugs may constitute a valuable adjunct in the treatment of nicotine-dependent behaviors.
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Affiliation(s)
- María Elena Quintanilla
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Paola Morales
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile.,Department of Neuroscience, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Fernando Ezquer
- Centro de Medicina Regenerativa, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Marcelo Ezquer
- Centro de Medicina Regenerativa, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Mario Herrera-Marschitz
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Yedy Israel
- Molecular and Clinical Pharmacology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
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11
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Raghu G, Berk M, Campochiaro PA, Jaeschke H, Marenzi G, Richeldi L, Wen FQ, Nicoletti F, Calverley PMA. The Multifaceted Therapeutic Role of N-Acetylcysteine (NAC) in Disorders Characterized by Oxidative Stress. Curr Neuropharmacol 2021; 19:1202-1224. [PMID: 33380301 PMCID: PMC8719286 DOI: 10.2174/1570159x19666201230144109] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/27/2020] [Accepted: 12/13/2020] [Indexed: 02/08/2023] Open
Abstract
Oxidative stress, which results in the damage of diverse biological molecules, is a ubiquitous cellular process implicated in the etiology of many illnesses. The sulfhydryl-containing tripeptide glutathione (GSH), which is synthesized and maintained at high concentrations in all cells, is one of the mechanisms by which cells protect themselves from oxidative stress. N-acetylcysteine (NAC), a synthetic derivative of the endogenous amino acid L-cysteine and a precursor of GSH, has been used for several decades as a mucolytic and as an antidote to acetaminophen (paracetamol) poisoning. As a mucolytic, NAC breaks the disulfide bonds of heavily cross-linked mucins, thereby reducing mucus viscosity. In vitro, NAC has antifibrotic effects on lung fibroblasts. As an antidote to acetaminophen poisoning, NAC restores the hepatic GSH pool depleted in the drug detoxification process. More recently, improved knowledge of the mechanisms by which NAC acts has expanded its clinical applications. In particular, the discovery that NAC can modulate the homeostasis of glutamate has prompted studies of NAC in neuropsychiatric diseases characterized by impaired glutamate homeostasis. This narrative review provides an overview of the most relevant and recent evidence on the clinical application of NAC, with a focus on respiratory diseases, acetaminophen poisoning, disorders of the central nervous system (chronic neuropathic pain, depression, schizophrenia, bipolar disorder, and addiction), cardiovascular disease, contrast-induced nephropathy, and ophthalmology (retinitis pigmentosa).
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Affiliation(s)
| | | | | | | | | | | | | | | | - Peter M. A. Calverley
- Address correspondence to this author at Clinical Science Centre, University Hospital Aintree, Longmoor Lane, Liverpool UK L9 7AL; Tel: +44 151 529 5886, Fax: +44 151 529 5888; E-mail:
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Neurodevelopmental signatures of narcotic and neuropsychiatric risk factors in 3D human-derived forebrain organoids. Mol Psychiatry 2021; 26:7760-7783. [PMID: 34158620 PMCID: PMC8873021 DOI: 10.1038/s41380-021-01189-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/20/2021] [Accepted: 06/01/2021] [Indexed: 02/06/2023]
Abstract
It is widely accepted that narcotic use during pregnancy and specific environmental factors (e.g., maternal immune activation and chronic stress) may increase risk of neuropsychiatric illness in offspring. However, little progress has been made in defining human-specific in utero neurodevelopmental pathology due to ethical and technical challenges associated with accessing human prenatal brain tissue. Here we utilized human induced pluripotent stem cells (hiPSCs) to generate reproducible organoids that recapitulate dorsal forebrain development including early corticogenesis. We systemically exposed organoid samples to chemically defined "enviromimetic" compounds to examine the developmental effects of various narcotic and neuropsychiatric-related risk factors within tissue of human origin. In tandem experiments conducted in parallel, we modeled exposure to opiates (μ-opioid agonist endomorphin), cannabinoids (WIN 55,212-2), alcohol (ethanol), smoking (nicotine), chronic stress (human cortisol), and maternal immune activation (human Interleukin-17a; IL17a). Human-derived dorsal forebrain organoids were consequently analyzed via an array of unbiased and high-throughput analytical approaches, including state-of-the-art TMT-16plex liquid chromatography/mass-spectrometry (LC/MS) proteomics, hybrid MS metabolomics, and flow cytometry panels to determine cell-cycle dynamics and rates of cell death. This pipeline subsequently revealed both common and unique proteome, reactome, and metabolome alterations as a consequence of enviromimetic modeling of narcotic use and neuropsychiatric-related risk factors in tissue of human origin. However, of our 6 treatment groups, human-derived organoids treated with the cannabinoid agonist WIN 55,212-2 exhibited the least convergence of all groups. Single-cell analysis revealed that WIN 55,212-2 increased DNA fragmentation, an indicator of apoptosis, in human-derived dorsal forebrain organoids. We subsequently confirmed induction of DNA damage and apoptosis by WIN 55,212-2 within 3D human-derived dorsal forebrain organoids. Lastly, in a BrdU pulse-chase neocortical neurogenesis paradigm, we identified that WIN 55,212-2 was the only enviromimetic treatment to disrupt newborn neuron numbers within human-derived dorsal forebrain organoids. Cumulatively this study serves as both a resource and foundation from which human 3D biologics can be used to resolve the non-genomic effects of neuropsychiatric risk factors under controlled laboratory conditions. While synthetic cannabinoids can differ from naturally occurring compounds in their effects, our data nonetheless suggests that exposure to WIN 55,212-2 elicits neurotoxicity within human-derived developing forebrain tissue. These human-derived data therefore support the long-standing belief that maternal use of cannabinoids may require caution so to avoid any potential neurodevelopmental effects upon developing offspring in utero.
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13
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Cano-Cebrián MJ, Fernández-Rodríguez S, Hipólito L, Granero L, Polache A, Zornoza T. Efficacy of N-acetylcysteine in the prevention of alcohol relapse-like drinking: Study in long-term ethanol-experienced male rats. J Neurosci Res 2020; 99:638-648. [PMID: 33063355 DOI: 10.1002/jnr.24736] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 09/07/2020] [Accepted: 10/01/2020] [Indexed: 02/06/2023]
Abstract
Alcohol use disorders are chronic and highly relapsing disorders, thus alcoholic patients have a high rate of recidivism for drug use even after long periods of abstinence. The literature points to the potential usefulness of N-acetylcysteine (NAC) in the management of several substance use disorders probably due to its capacity to restore brain homeostasis of the glutamate system disrupted in addiction. However, there is little evidence in the case of alcohol. The aim of this study was to explore the potential anti-relapse efficacy of NAC using the alcohol deprivation effect (ADE) model in long-term experienced rats. Two experiments were performed in male Wistar rats to: (a) test the efficacy of NAC to prevent relapse and (b) discriminate the best administration schedule (intermittent vs. continuous) for NAC. In the first experiment, animals were implanted with mini-osmotic pumps delivering 0 or 1 mg/hr NAC during 14 days. In a second experiment, rats received 0, 60, or 100 mg/kg once daily by subcutaneous injection. The efficacy to prevent ADE was evaluated in both experiments. NAC subcutaneously administered, either by continuous infusion or by intermittent injections regimen, is able to block the ADE. The best results were obtained after using 60 mg/kg NAC dose. Our findings support the hypothesis that NAC may represent a valuable therapy in the management of alcohol relapse.
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Affiliation(s)
- María José Cano-Cebrián
- Departament de Farmàcia i Tecnologia Farmacèutica i Parasitologia, Universitat de València, Burjassot, Spain
| | - Sandra Fernández-Rodríguez
- Departament de Farmàcia i Tecnologia Farmacèutica i Parasitologia, Universitat de València, Burjassot, Spain
| | - Lucia Hipólito
- Departament de Farmàcia i Tecnologia Farmacèutica i Parasitologia, Universitat de València, Burjassot, Spain
| | - Luis Granero
- Departament de Farmàcia i Tecnologia Farmacèutica i Parasitologia, Universitat de València, Burjassot, Spain
| | - Ana Polache
- Departament de Farmàcia i Tecnologia Farmacèutica i Parasitologia, Universitat de València, Burjassot, Spain
| | - Teodoro Zornoza
- Departament de Farmàcia i Tecnologia Farmacèutica i Parasitologia, Universitat de València, Burjassot, Spain
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14
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Kumar M, Adeluyi A, Anderson EL, Turner JR. Glial cells as therapeutic targets for smoking cessation. Neuropharmacology 2020; 175:108157. [PMID: 32461156 PMCID: PMC7791555 DOI: 10.1016/j.neuropharm.2020.108157] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 12/17/2022]
Abstract
Smoking remains the leading cause of morbidity and mortality in the United States, with less than 5% of smokers attempting to quit succeeding. This low smoking cessation success rate is thought to be due to the long-term adaptations and alterations in synaptic plasticity that occur following chronic nicotine exposure and withdrawal. Glial cells have recently emerged as active players in the development of dependence phenotypes due to their roles in modulating neuronal functions and synaptic plasticity. Fundamental studies have demonstrated that microglia and astrocytes are crucial for synapse formation and elimination in the developing brain, likely contributing to why glial dysfunction is implicated in numerous neurological and psychiatric disorders. Recently, there is increasing evidence for the involvement of glial cells in drug dependence and its associated behavioral manifestations. This review summarizes the newly evaluated role of microglia and astrocytes as molecular drivers of nicotine dependence and withdrawal phenotypes. This article is part of the special issue on 'Contemporary Advances in Nicotine Neuropharmacology.
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Affiliation(s)
- Mohit Kumar
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, KY, USA.
| | - Adewale Adeluyi
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, KY, USA; Ann Romney Center for Neurologic Disease, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Erin L Anderson
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, USA.
| | - Jill R Turner
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, KY, USA.
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15
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Namba MD, Kupchik YM, Spencer SM, Garcia‐Keller C, Goenaga JG, Powell GL, Vicino IA, Hogue IB, Gipson CD. Accumbens neuroimmune signaling and dysregulation of astrocytic glutamate transport underlie conditioned nicotine-seeking behavior. Addict Biol 2020; 25:e12797. [PMID: 31330570 PMCID: PMC7323912 DOI: 10.1111/adb.12797] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 05/18/2019] [Accepted: 05/23/2019] [Indexed: 12/16/2022]
Abstract
Nicotine self-administration is associated with decreased expression of the glial glutamate transporter (GLT-1) and the cystine-glutamate exchange protein xCT within the nucleus accumbens core (NAcore). N-acetylcysteine (NAC) has been shown to restore these proteins in a rodent model of drug addiction and relapse. However, the specific molecular mechanisms driving its inhibitory effects on cue-induced nicotine reinstatement are unknown. Here, we confirm that extinction of nicotine-seeking behavior is associated with impaired NAcore GLT-1 function and expression and demonstrates that reinstatement of nicotine seeking rapidly enhances membrane fraction GLT-1 expression. Extinction and cue-induced reinstatement of nicotine seeking was also associated with increased tumor necrosis factor alpha (TNFα) and decreased glial fibrillary acidic protein (GFAP) expression in the NAcore. NAC treatment (100 mg/kg/day, i.p., for 5 d) inhibited cue-induced nicotine seeking and suppressed AMPA to NMDA current ratios, suggesting that NAC reduces NAcore postsynaptic excitability. In separate experiments, rats received NAC and an antisense vivo-morpholino to selectively suppress GLT-1 expression in the NAcore during extinction and were subsequently tested for cue-induced reinstatement of nicotine seeking. NAC treatment rescued NAcore GLT-1 expression and attenuated cue-induced nicotine seeking, which was blocked by GLT-1 antisense. NAC also reduced TNFα expression in the NAcore. Viral manipulation of the NF-κB pathway, which is downstream of TNFα, revealed that cue-induced nicotine seeking is regulated by NF-κB pathway signaling in the NAcore independent of GLT-1 expression. Ultimately, these results are the first to show that immunomodulatory mechanisms may regulate known nicotine-induced alterations in glutamatergic plasticity that mediate cue-induced nicotine-seeking behavior.
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Affiliation(s)
- Mark D. Namba
- Department of PsychologyArizona State University Tempe AZ USA
| | - Yonatan M. Kupchik
- Department of Medical NeurobiologyHebrew University of Jerusalem Jerusalem Israel
| | - Sade M. Spencer
- Department of PharmacologyUniversity of Minnesota Minneapolis MN USA
| | | | | | - Gregory L. Powell
- Department of PsychologyArizona State University Tempe AZ USA
- School of Life SciencesArizona State University Tempe AZ USA
| | - Ian A. Vicino
- School of Life SciencesArizona State University Tempe AZ USA
- Center for Immunotherapy, Vaccines, and Virotherapy, Biodesign InstituteArizona State University Tempe AZ USA
| | - Ian B. Hogue
- School of Life SciencesArizona State University Tempe AZ USA
- Center for Immunotherapy, Vaccines, and Virotherapy, Biodesign InstituteArizona State University Tempe AZ USA
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16
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Abstract
The pervasive and devastating nature of substance use disorders underlies the need for the continued development of novel pharmacotherapies. We now know that glia play a much greater role in neuronal processes than once believed. The various types of glial cells (e.g., astrocytes, microglial, oligodendrocytes) participate in numerous functions that are crucial to healthy central nervous system function. Drugs of abuse have been shown to interact with glia in ways that directly contribute to the pharmacodynamic effects responsible for their abuse potential. Through their effect upon glia, drugs of abuse also alter brain function resulting in behavioral changes associated with substance use disorders. Therefore, drug-induced changes in glia and inflammation within the central nervous system (neuroinflammation) have been investigated to treat various aspects of drug abuse and dependence. This article presents a brief overview of the effects of each of the major classes of addictive drugs on glia. Next, the paper reviews the pre-clinical and clinical studies assessing the effects that glial modulators have on abuse-related behavioral effects, such as pleasure, withdrawal, and motivation. There is a strong body of pre-clinical literature demonstrating the general effectiveness of several glia-modulating drugs in models of reward and relapse. Clinical studies have also yielded promising results, though not as robust. There is still much to disentangle regarding the integration between addictive drugs and glial cells. Improved understanding of the relationship between glia and the pathophysiology of drug abuse should allow for more precise exploration in the development and testing of glial-directed treatments for substance use disorders.
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Affiliation(s)
- Jermaine D. Jones
- Division on Substance Use Disorders, New York State Psychiatric Institute and Columbia University Vagelos College of Physicians and Surgeons, 1051 Riverside Drive, New York, NY 10032, USA
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Nicotine reduction does not alter essential value of nicotine or reduce cue-induced reinstatement of nicotine seeking. Drug Alcohol Depend 2020; 212:108020. [PMID: 32362438 PMCID: PMC7293915 DOI: 10.1016/j.drugalcdep.2020.108020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 03/09/2020] [Accepted: 04/13/2020] [Indexed: 01/10/2023]
Abstract
Reduction of nicotine content in tobacco products is a regulatory control strategy intended to decrease smoking dependence, and is hypothesized to produce gradual reductions of nicotine intake. Rats were initially trained to self-administer 0.06 mg/kg/infusion nicotine (Phase 1), which was followed by a threshold procedure to determine nicotine demand via a behavioral economics (BE) paradigm (Phase 2). Rats then either self-administered the training dose (high dose group), or were switched to a low dose of nicotine (0.001 mg/kg/infusion; low dose group) in Phase 3. Both groups then underwent a second threshold procedure and demand curves were re-determined (Phase 4). In Phase 5, responding for nicotine was extinguished over the course of 21 sessions. Cue-induced reinstatement was then evaluated (Phase 6). Rats in the low dose group maintained a steady amount of infusions, and thus, did not compensate for nicotine reduction. Rats in the low dose group also showed similar demand elasticity and nicotine seeking (Phase 6) compared to the high dose group, indicating that nicotine reduction did not decrease nicotine demand or seeking. Further, both groups displayed resistance to extinction, indicating that nicotine reduction did not facilitate extinction learning. These results suggest that although compensation of intake does not occur, decreasing the dose of nicotine does not alter nicotine reinforcement value or relapse vulnerability. Further, these results indicate persistence of nicotine-motivated behavior after self-administration of a low nicotine dose. Translationally, these results suggest that alternative strategies may be needed to achieve positive smoking cessation outcomes.
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18
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Leyrer-Jackson JM, Piña JA, McCallum J, Foster Olive M, Gipson CD. Direct administration of ifenprodil and citalopram into the nucleus accumbens inhibits cue-induced nicotine seeking and associated glutamatergic plasticity. Brain Struct Funct 2020; 225:1967-1978. [PMID: 32591928 DOI: 10.1007/s00429-020-02103-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 06/16/2020] [Indexed: 12/27/2022]
Abstract
Nicotine use disorder has been associated with glutamatergic alterations within the basal ganglia that might contribute to relapse. Specifically, initiation of cue-induced nicotine seeking produces rapid, transient synaptic potentiation (t-SP) in nucleus accumbens core (NAcore) medium spiny neurons (MSNs), defined as increases in spine head diameter and AMPA to NMDA current ratios (A/N). Ifenprodil, which inhibits nicotine reinstatement when administered systemically, antagonizes GluN2B-containing NMDA receptors, has affinity for serotonin receptors, and blocks serotonin transporters (SERT). The mechanisms underlying its therapeutic efficacy, however, remain unknown. Using pharmacological and genetic approaches, the current study examined the role of NAcore GluN2B receptors as well as SERT in mediating cue-induced nicotine seeking and associated MSN structure and physiology. Prior to reinstatement, rats received intra-NAcore injections of either ifenprodil, citalopram or artificial cerebral spinal fluid (15 min prior), or GluN2B or control siRNAs (3 consecutive days prior). Rats were sacrificed after a 15-min cue-induced reinstatement session for dendritic spine analysis, western blotting or whole-cell electrophysiology. Intra-NAcore ifenprodil blocked nicotine-seeking behavior and promoted a higher frequency of shorter spines on MSN dendrites. However, a decrease in membrane-bound GluN2B receptor expression did not prevent cue-induced nicotine seeking or associated MSN cell physiology. Interestingly, intra-NAcore citalopram, an SSRI, prevented cue-induced nicotine seeking. Together, these results indicate that the therapeutic effects of ifenprodil on cue-induced nicotine seeking may, in part, be due to its actions at SERT rather than GluN2B, which may be specific to nicotine-seeking as opposed to other drugs of abuse.
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Affiliation(s)
| | - Jose A Piña
- Department of Psychology, Arizona State University, Tempe, AZ, USA
| | - Joseph McCallum
- Department of Psychology, Arizona State University, Tempe, AZ, USA
| | - M Foster Olive
- Department of Psychology, Arizona State University, Tempe, AZ, USA
| | - Cassandra D Gipson
- Department of Family and Community Medicine, University of Kentucky, 741 S. Limestone, BBSRB Room 363, Lexington, KY, 40536, USA.
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19
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Siemsen BM, Reichel CM, Leong KC, Garcia-Keller C, Gipson CD, Spencer S, McFaddin JA, Hooker KN, Kalivas PW, Scofield MD. Effects of Methamphetamine Self-Administration and Extinction on Astrocyte Structure and Function in the Nucleus Accumbens Core. Neuroscience 2019; 406:528-541. [PMID: 30926546 PMCID: PMC6545487 DOI: 10.1016/j.neuroscience.2019.03.040] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 03/15/2019] [Accepted: 03/19/2019] [Indexed: 01/01/2023]
Abstract
Astrocytes provide support for neurons, regulate metabolic processes, and influence neuronal communication in a variety of ways, including through the homeostatic regulation of glutamate. Following 2-h cocaine or methamphetamine self-administration (SA) and extinction, rodents display decreased levels of basal glutamate in the nucleus accumbens core (NAcore), which transitions to elevated glutamate levels during drug seeking. We hypothesized that, like cocaine, this glutamate 'overflow' during methamphetamine seeking arises via decreased expression of the astroglial glutamate transporter GLT-1, and withdrawal of perisynaptic astroglial processes (PAPs) from synapses. As expected, methamphetamine self-administration and extinction decreased the level of contact made by PAPs in the NAcore, yet did not impact glutamate uptake, GLT-1 expression, or the general structural characteristics of astrocytes. Interestingly, systemic administration of N-acetylcysteine (NAC), a drug that both upregulates GLT-1 and promotes glial-glutamate release, reduced cued methamphetamine seeking. In order to test the impact of astrocyte activation and the induction of glial glutamate release within the NAcore, we employed astrocyte-specific expression of designer receptors exclusively activated by designer drugs (DREADDs). We show here that acute activation of Gq-coupled DREADDs in this region inhibited cued methamphetamine seeking. Taken together, these data indicate that cued methamphetamine seeking following two-hour SA is not mediated by deficient glutamate clearance in the NAcore, yet can be inhibited by engaging NAcore astrocytes.
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Affiliation(s)
- B M Siemsen
- Department of Anesthesiology and Perioperative Medicine, Medical University of South Carolina, Charleston, SC, USA; Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
| | - C M Reichel
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
| | - K C Leong
- Department of Psychology, Trinity University, San Antonio, TX, USA
| | - C Garcia-Keller
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
| | - C D Gipson
- Department of Psychology, Arizona State University, Tempe, AZ, USA
| | - S Spencer
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, USA
| | - J A McFaddin
- Department of Anesthesiology and Perioperative Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - K N Hooker
- Department of Anesthesiology and Perioperative Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - P W Kalivas
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
| | - M D Scofield
- Department of Anesthesiology and Perioperative Medicine, Medical University of South Carolina, Charleston, SC, USA; Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA.
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