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de Melo Bastos Cavalcante C, Bruno Oliveira K, Maria Araújo de Souza F, Maria Jatobá Hasten Reiter M, Rodrigues Melo da Silva B, Lavínia da Silva Oliveira K, Vinicius Dos Santos Sales M, Larissa Dias Pacheco A, Santos Siqueira E, de Araújo Costa M, Gomes Dos Santos Neto J, Gabriely Duarte Torres R, Catarina R Leite A, Santana de Melo I, Salgueiro Machado S, Duzzioni M, Leite Góes Gitaí D, Wagner de Castro O. Crack cocaine inhalation increases seizure susceptibility by reducing acetylcholinesterase activity. Epilepsy Behav 2024; 156:109832. [PMID: 38761450 DOI: 10.1016/j.yebeh.2024.109832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 05/02/2024] [Accepted: 05/07/2024] [Indexed: 05/20/2024]
Abstract
Crack cocaine is a highly addictive and potent stimulant drug. Animal studies have shown that the cholinergic system plays a role in neurotoxicity induced by cocaine or its active metabolites inhalation. Behavioral alterations associated with crack cocaine use include hyperactivity, depressed mood, and decreased seizure threshold. Here we evaluate the acetylcholinesterase (AChE) and reactive oxygen species (ROS) activity, behavioral profile, and the threshold for epileptic seizures in rats that received intrahippocampal pilocarpine (H-PILO) followed by exposure to crack cocaine (H-PILO + CRACK). Animals exposed to H-PILO + CRACK demonstrated increased severity and frequency of limbic seizures. The AChE activity was reduced in the groups exposed to crack cocaine alone (CRACK) and H-PILO + CRACK, whereas levels of ROS remained unchanged. In addition, crack cocaine exposure increased vertical locomotor activity, without changing water and sucrose intake. Short-term memory consolidation remained unchanged after H-PILO, H-PILO + CRACK, and CRACK administration. Overall, our data suggest that crack cocaine inhalation reduced the threshold for epileptic seizures in rats submitted to low doses of pilocarpine through the inhibition of AChE. Taken together, our findings can be useful in the development of effective strategies for preventing and treating the harmful effects of cocaine and crack cocaine on the central nervous system.
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Affiliation(s)
| | - Kellysson Bruno Oliveira
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Fernanda Maria Araújo de Souza
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | | | - Bianca Rodrigues Melo da Silva
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | | | | | - Amanda Larissa Dias Pacheco
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Edite Santos Siqueira
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Maisa de Araújo Costa
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - José Gomes Dos Santos Neto
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Rayssa Gabriely Duarte Torres
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Ana Catarina R Leite
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Igor Santana de Melo
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Sônia Salgueiro Machado
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Marcelo Duzzioni
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Daniel Leite Góes Gitaí
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Olagide Wagner de Castro
- Department of Physiology, Institute of Biological Science and Health of Federal University of Alagoas, Maceió, Alagoas, Brazil.
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Chivero ET, Sil S, Singh S, Thangaraj A, Gordon L, Evah-Nzoughe GB, Ferguson N, Callen S, Buch S. Protective Role of Lactobacillus rhamnosus Probiotic in Reversing Cocaine-Induced Oxidative Stress, Glial Activation and Locomotion in Mice. J Neuroimmune Pharmacol 2022; 17:62-75. [PMID: 34628571 DOI: 10.1007/s11481-021-10020-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 08/30/2021] [Indexed: 12/29/2022]
Abstract
Cocaine abuse is known to cause inflammation, oxidative injury and alterations in the gut microbiota. Although emerging studies have demonstrated the role of gut microbiota in modulating neurological complications and behavior, the mechanism(s) underlying these processes remain unclear. In the present study, we investigated the protective effect of Lactobacillus rhamnosus probiotic on cocaine-induced oxidative stress, glial activation, and locomotion in mice. In this study, groups of male C56BL6 mice were administered gut-resident commensal bacteria L. rhamnosus probiotic (oral gavage) concurrently with cocaine (20 mg/kg, i.p.) or saline for 28 days and assessed for oxidative stress and cellular activation in both the gut and brain as well as alterations in locomotion behavior. Cocaine-induced gut dysregulation was associated with increased formation of 4-hydroxynonenal (4-HNE) adducts, increased expression of pERK-1/2, pNF-kB-p65 and antioxidant mediators (SOD1, GPx1). In cocaine administered mice, there was increased activation of both microglia and astrocytes in the striatum and cortex of the brain as shown by enhanced expression of CD11b and GFAP, respectively. Cocaine administration also resulted in increased locomotor activity in the open field test in these mice. Administration of L. rhamnosus attenuated cocaine-induced gut oxidative stress and inflammation as well as glial activation and locomotion. These results suggest the potential of microbial-based interventions to attenuate cocaine-mediated behavioral responses and neuroinflammation, in addition to systemic inflammation and oxidative damage.
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Affiliation(s)
- Ernest T Chivero
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
| | - Susmita Sil
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Seema Singh
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Annadurai Thangaraj
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Lila Gordon
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Grace B Evah-Nzoughe
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Natasha Ferguson
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Shannon Callen
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Shilpa Buch
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
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Oxidative Stress and Cocaine Intoxication as Start Points in the Pathology of Cocaine-Induced Cardiotoxicity. TOXICS 2021; 9:toxics9120317. [PMID: 34941752 PMCID: PMC8705810 DOI: 10.3390/toxics9120317] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/12/2021] [Accepted: 11/20/2021] [Indexed: 01/03/2023]
Abstract
Psychomotor stimulants are the most commonly used prohibited substances after cannabis. Globally, their use reaches epidemiological proportions and is one of the most common causes of death in many countries. The use of illicit drugs has negative effects on the cardiovascular system and is one of the causes of serious cardiovascular pathologies, ranging from abnormal heart rhythms to heart attacks and sudden cardiac death. The reactive oxygen species generation, toxic metabolites formation, and oxidative stress play a significant role in cocaine-induced cardiotoxicity. The aim of the present review is to assess acute and chronic cocaine toxicity by focusing on the published literature regarding oxidative stress levels. Hypothetically, this study can serve as a basis for developing a rapid and effective method for determining oxidative stress levels by monitoring changes in the redox status of patients with cocaine intoxication.
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Mai HN, Sharma N, Jeong JH, Shin EJ, Pham DT, Trinh QD, Lee YJ, Jang CG, Nah SY, Bing G, Kim HC. P53 knockout mice are protected from cocaine-induced kindling behaviors via inhibiting mitochondrial oxidative burdens, mitochondrial dysfunction, and proapoptotic changes. Neurochem Int 2019; 124:68-81. [DOI: 10.1016/j.neuint.2018.12.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Revised: 12/21/2018] [Accepted: 12/28/2018] [Indexed: 11/30/2022]
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Impairment of spatial working memory and oxidative stress induced by repeated crack cocaine inhalation in rats. Behav Brain Res 2019; 359:910-917. [DOI: 10.1016/j.bbr.2018.06.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 05/30/2018] [Accepted: 06/20/2018] [Indexed: 11/17/2022]
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Tong J, Fitzmaurice PS, Moszczynska A, Rathitharan G, Ang LC, Meyer JH, Mizrahi R, Boileau I, Furukawa Y, McCluskey T, Sailasuta N, Kish SJ. Normal glutathione levels in autopsied brain of chronic users of heroin and of cocaine. Drug Alcohol Depend 2018; 190:20-28. [PMID: 29960919 PMCID: PMC6078812 DOI: 10.1016/j.drugalcdep.2018.05.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 05/08/2018] [Accepted: 05/22/2018] [Indexed: 01/06/2023]
Abstract
BACKGROUND Animal studies suggest that exposure to either of the two widely used drugs of abuse, heroin or cocaine, causes depletion of the antioxidant, reduced glutathione, a hallmark of oxidative stress, in the brain. However, the relevance of the animal findings to the human is uncertain and clinical trials with the antioxidant GSH precursor n-acetylcysteine have produced mixed results in cocaine dependence. METHODS Our major objective was to compare glutathione levels, determined by an HPLC-coulometric procedure, in autopsied brain of chronic heroin (n = 11) and cocaine users (n = 9), who were positive for the drugs in the brain, to those of matched controls (n = 16). Six brain regions were examined, including caudate, hippocampus, thalamus and frontal, temporal and insular cortices. RESULTS In contrast to experimental animal findings, we found no statistically significant difference between mean levels of reduced or oxidized glutathione in the drug user vs. control groups. Moreover, no correlation was found between levels of drugs in the brain and those of glutathione. CONCLUSIONS Acknowledging the many generic limitations of an autopsied human brain study and the preliminary nature of the findings, our data nevertheless suggest that any oxidative stress caused by heroin or cocaine in chronic users of the drugs might not be sufficient to cause substantial loss of stores of glutathione in the human brain, at least during early withdrawal. These findings, requiring replication, might also have some relevance to future clinical trials employing glutathione supplement therapy as an anti-oxidative strategy in chronic users of the two abused drugs.
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Affiliation(s)
- Junchao Tong
- Preclinical Imaging Unit, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada; Human Brain Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada; Addiction Imaging Research Group, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada.
| | | | - Anna Moszczynska
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI, USA
| | - Gausiha Rathitharan
- Human Brain Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada,Addiction Imaging Research Group, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Lee-Cyn Ang
- Division of Neuropathology, London Health Sciences Centre, University of Western Ontario, London, ON, Canada
| | - Jeffrey H Meyer
- Research Imaging Centre and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Romina Mizrahi
- Research Imaging Centre, Centre for Addiction and Mental Health; Institute of Medical Science, Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Isabelle Boileau
- Addiction Imaging Research Group, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Yoshiaki Furukawa
- Department of Neurology, Juntendo Tokyo Koto Geriatric Medical Center, Faculty of Medicine, University and Post Graduate University of Juntendo, Tokyo, Japan
| | - Tina McCluskey
- Human Brain Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Napapon Sailasuta
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Stephen J. Kish
- Human Brain Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
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Jang EY, Yang CH, Hedges DM, Kim SP, Lee JY, Ekins TG, Garcia BT, Kim HY, Nelson AC, Kim NJ, Steffensen SC. The role of reactive oxygen species in methamphetamine self-administration and dopamine release in the nucleus accumbens. Addict Biol 2017; 22:1304-1315. [PMID: 27417190 DOI: 10.1111/adb.12419] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 05/10/2016] [Accepted: 05/13/2016] [Indexed: 12/30/2022]
Abstract
Methamphetamine (METH) markedly increases dopamine (DA) release in the mesolimbic DA system, which plays an important role in mediating the reinforcing effects of METH. METH-induced DA release results in the formation of reactive oxygen species (ROS), leading to oxidative damage. We have recently reported that ROS are implicated in behavior changes and DA release in the nucleus accumbens (NAc) following cocaine administration. The aim of this study was to evaluate the involvement of ROS in METH-induced locomotor activity, self-administration and enhancement of DA release in the NAc. Systemic administration of a non-specific ROS scavenger, N-tert-butyl-α-phenylnitrone (PBN; 0, 50 and 75 mg/kg, IP) or a superoxide-selective scavenger, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL; 0, 50 and 100 mg/kg, IP), attenuated METH-induced locomotor activity without affecting generalized behavior in METH-naïve rats. PBN and TEMPOL significantly attenuated METH self-administration without affecting food intake. Increased oxidative stress was found in neurons, but not astrocytes, microglia or oligodendrocytes, in the NAc of METH self-administering rats. In addition, TEMPOL significantly decreased METH enhancement of DA release in the NAc. Taken together, these results suggest that enhancement of ROS in the NAc contributes to the reinforcing effect of METH.
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Affiliation(s)
- Eun Young Jang
- Department of Psychology and Center for Neuroscience; Brigham Young University; Provo UT USA
- College of Korean Medicine; Daegu Haany University; Daegu South Korea
| | - Chae Ha Yang
- College of Korean Medicine; Daegu Haany University; Daegu South Korea
| | - David M. Hedges
- Department of Psychology and Center for Neuroscience; Brigham Young University; Provo UT USA
| | - Soo Phil Kim
- College of Korean Medicine; Daegu Haany University; Daegu South Korea
| | - Jun Yeon Lee
- College of Korean Medicine; Daegu Haany University; Daegu South Korea
| | - Tyler G. Ekins
- Department of Psychology and Center for Neuroscience; Brigham Young University; Provo UT USA
| | - Brandon T. Garcia
- Department of Psychology and Center for Neuroscience; Brigham Young University; Provo UT USA
| | - Hee Young Kim
- College of Korean Medicine; Daegu Haany University; Daegu South Korea
| | - Ashley C. Nelson
- Department of Psychology and Center for Neuroscience; Brigham Young University; Provo UT USA
| | - Nam Jun Kim
- College of Korean Medicine; Daegu Haany University; Daegu South Korea
| | - Scott C. Steffensen
- Department of Psychology and Center for Neuroscience; Brigham Young University; Provo UT USA
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Cannabidiol rescues acute hepatic toxicity and seizure induced by cocaine. Mediators Inflamm 2015; 2015:523418. [PMID: 25999668 PMCID: PMC4427116 DOI: 10.1155/2015/523418] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 04/07/2015] [Indexed: 12/17/2022] Open
Abstract
Cocaine is a commonly abused illicit drug that causes significant morbidity and mortality. The most severe and common complications are seizures, ischemic strokes, myocardial infarction, and acute liver injury. Here, we demonstrated that acute cocaine intoxication promoted seizure along with acute liver damage in mice, with intense inflammatory infiltrate. Considering the protective role of the endocannabinoid system against cell toxicity, we hypothesized that treatment with an anandamide hydrolysis inhibitor, URB597, or with a phytocannabinoid, cannabidiol (CBD), protects against cocaine toxicity. URB597 (1.0 mg/kg) abolished cocaine-induced seizure, yet it did not protect against acute liver injury. Using confocal liver intravital microscopy, we observed that CBD (30 mg/kg) reduced acute liver inflammation and damage induced by cocaine and prevented associated seizure. Additionally, we showed that previous liver damage induced by another hepatotoxic drug (acetaminophen) increased seizure and lethality induced by cocaine intoxication, linking hepatotoxicity to seizure dynamics. These findings suggest that activation of cannabinoid system may have protective actions on both liver and brain induced by cocaine, minimizing inflammatory injury promoted by cocaine, supporting its further clinical application in the treatment of cocaine abuse.
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Glutathione and redox signaling in substance abuse. Biomed Pharmacother 2014; 68:799-807. [PMID: 25027386 DOI: 10.1016/j.biopha.2014.06.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 06/12/2014] [Indexed: 01/04/2023] Open
Abstract
Throughout the last couple decades, the cause and consequences of substance abuse has expanded to identify the underlying neurobiological signaling mechanisms associated with addictive behavior. Chronic use of drugs, such as cocaine, methamphetamine and alcohol leads to the formation of oxidative or nitrosative stress (ROS/RNS) and changes in glutathione and redox homeostasis. Of importance, redox-sensitive post-translational modifications on cysteine residues, such as S-glutathionylation and S-nitrosylation could impact on the structure and function of addiction related signaling proteins. In this commentary, we evaluate the role of glutathione and redox signaling in cocaine-, methamphetamine- and alcohol addiction and conclude by discussing the possibility of targeting redox pathways for the therapeutic intervention of these substance abuse disorders.
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Matos G, Scorza FA, Cavalheiro EA, Tufik S, Andersen ML. PDEI‐5 for Erectile Dysfunction: A Potential Role in Seizure Susceptibility. J Sex Med 2012; 9:2111-21. [DOI: 10.1111/j.1743-6109.2012.02780.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Pomierny-Chamioło L, Moniczewski A, Wydra K, Suder A, Filip M. Oxidative stress biomarkers in some rat brain structures and peripheral organs underwent cocaine. Neurotox Res 2012; 23:92-102. [PMID: 22791409 PMCID: PMC3526736 DOI: 10.1007/s12640-012-9335-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 04/16/2012] [Accepted: 06/07/2012] [Indexed: 12/14/2022]
Abstract
Oxidative stress (OS) generates or intensifies cocaine-evoked toxicity in the brain and peripheral organs. The aim of this study was to examine superoxide dismutase (SOD) activity and lipid peroxidation [measured by malondialdehyde (MDA) levels] in rats during maintenance of cocaine self-administration and after withdrawal by a yoked-triad procedure. Our results indicate that repeated cocaine self-administration provoked an elevation of SOD activity in the hippocampus, frontal cortex, dorsal striatum, and liver. MDA levels were reduced in the brain, increased in the liver, kidney, and heart during maintenance of self-administration, and increased in the kidney in cocaine-yoked rats. In addition, following extinction training, we found enhanced MDA levels and SOD activity in the rat hippocampus, while changes in the activity of OS biomarkers in other brain structures and peripheral tissues were reminiscent of the changes seen during cocaine self-administration. These findings highlight the association between OS biomarkers in motivational processes related to voluntary cocaine intake in rats. OS participates in memory and learning impairments that could be involved in drug toxicity and addiction mechanisms. Therefore, further studies are necessary to address protective mechanisms against cocaine-induced brain and peripheral tissue damage.
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Affiliation(s)
- Lucyna Pomierny-Chamioło
- Department of Toxicology, Faculty of Pharmacy, Medical College, Jagiellonian University, Medyczna 9, 30-688 Kraków, Poland.
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Cocaine-induced adaptations in cellular redox balance contributes to enduring behavioral plasticity. Neuropsychopharmacology 2011; 36:2551-60. [PMID: 21796101 PMCID: PMC3194081 DOI: 10.1038/npp.2011.143] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Impaired glutamate homeostasis in the nucleus accumbens has been linked to cocaine relapse in animal models, and results in part from cocaine-induced downregulation of the cystine-glutamate exchanger. In addition to regulating extracellular glutamate, the uptake of cystine by the exchanger is a rate-limiting step in the synthesis of glutathione (GSH). GSH is critical for balancing cellular redox in response to oxidative stress. Cocaine administration induces oxidative stress, and we first determined if downregulated cystine-glutamate exchange alters redox homeostasis in rats withdrawn from daily cocaine injections and then challenged with acute cocaine. Among the daily cocaine-induced changes in redox homeostasis were an increase in protein S-glutathionylation and a decrease in expression of GSH-S-transferase pi (GSTpi). To mimic reduced GSTpi, a genetic mouse model of GSTpi deletion or pharmacological inhibition of GSTpi by administering ketoprofen during daily cocaine administration was used. The capacity of cocaine to induce conditioned place preference or locomotor sensitization was augmented, indicating that reducing GSTpi may contribute to cocaine-induced behavioral neuroplasticity. Conversely, an acute cocaine challenge after withdrawal from daily cocaine elicited a marked increase in accumbens GSTpi, and the expression of behavioral sensitization to a cocaine challenge injection was inhibited by ketoprofen pretreatment; supporting a protective effect by the acute cocaine-induced rise in GSTpi. Together, these data indicate that cocaine-induced oxidative stress induces changes in GSTpi that contribute to cocaine-induced behavioral plasticity.
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