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Rieder AS, Ramires Júnior OV, Prauchner GRK, Wyse ATS. Effects of methylphenidate on mitochondrial dynamics and bioenergetics in the prefrontal cortex of juvenile rats are sex-dependent. Prog Neuropsychopharmacol Biol Psychiatry 2024; 134:111057. [PMID: 38880464 DOI: 10.1016/j.pnpbp.2024.111057] [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: 12/07/2023] [Revised: 05/31/2024] [Accepted: 06/12/2024] [Indexed: 06/18/2024]
Abstract
Methylphenidate (MPH) is a central nervous system stimulant drug and a first order prescription in the treatment of Attention Deficit Hyperactivity Disorder (ADHD). Although MPH biochemistry in neurodevelopment is not completely understood, studies showed it alters energy metabolism in rat brains. ADHD prevalence during neurodevelopment is related to males and the investigation has been mainly done in these subjects, therefore, little is known about MPH action in females and, consequently, about sexual dimorphism. In the present study we evaluated markers of mitochondrial dynamics (DRP1 and MFN2, fission and fusion, respectively), biogenesis (mtTFA) and bioenergetics (respiratory chain complexes) in prefrontal cortex of male and female juvenile rats submitted to exposure to MPH to better understand MPH effect during postnatal neurodevelopment. ATP and oxidative stress levels were also evaluated. Wistar rats received intraperitoneal injection of MPH (2.0 mg/kg) or control (saline), once a day, from 15th to 45th day of age. Results showed that MPH increased DRP1 and decreased MFN2, as well as increased mtTFA in prefrontal cortex of male rats. In female, MPH decreased NRF1 and increased Parkin, which are mitochondrial regulatory proteins. Respiratory chain complexes (complex I, SDH, complexes III and IV), ATP production and oxidative stress parameters were altered and shown to be sex-dependent. Taken together, results suggest that chronic MPH exposure at an early age in healthy animals changes mitochondrial dynamics, biogenesis and bioenergetics differently depending on the sex of the subjects.
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Affiliation(s)
- Alessandra Schmitt Rieder
- Laboratory of Neuroprotection and Neurometabolic Diseases, Department of Biochemistry, ICBS, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil
| | - Osmar Vieira Ramires Júnior
- Laboratory of Neuroprotection and Neurometabolic Diseases, Department of Biochemistry, ICBS, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil
| | - Gustavo Ricardo Krupp Prauchner
- Laboratory of Neuroprotection and Neurometabolic Diseases, Department of Biochemistry, ICBS, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil
| | - Angela T S Wyse
- Laboratory of Neuroprotection and Neurometabolic Diseases, Department of Biochemistry, ICBS, Universidade Federal do Rio Grande do Sul (UFRGS), Rua Ramiro Barcelos, 2600-Anexo, 90035-003 Porto Alegre, RS, Brazil.
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Evidence of methylphenidate effect on mitochondria, redox homeostasis, and inflammatory aspects: Insights from animal studies. Prog Neuropsychopharmacol Biol Psychiatry 2022; 116:110518. [PMID: 35092763 DOI: 10.1016/j.pnpbp.2022.110518] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 01/19/2022] [Accepted: 01/21/2022] [Indexed: 11/22/2022]
Abstract
Methylphenidate (MPH) is a central nervous system (CNS) stimulant known for its effectiveness in the treatment of Attention Deficit Hyperactivity Disorder (ADHD), a neuropsychiatric condition that has a high incidence in childhood and affects behavior and cognition. However, the increase in its use among individuals who do not present all the diagnostic criteria for ADHD has become a serious public health problem since the neurological and psychiatric consequences of this unrestricted use are not widely known. In addition, since childhood is a critical period for the maturation of the CNS, the high prescription of MPH for preschool children also raises several concerns. This review brings new perspectives on how MPH (in different doses, routes of administration and ages) affects the CNS, focusing on animal studies that evaluated changes in mitochondrial (bioenergetics), redox balance and apoptosis, as well as inflammatory parameters. MPH alters brain energy homeostasis, increasing glucose consumption and impairing the activity of enzymes in the Krebs cycle and electron transport chain, as well as ATP levels and Na+,K+-ATPase activity. MPH induces oxidative stress, increasing the levels of reactive oxygen and nitrogen species and altering enzymatic and non-enzymatic antioxidant defenses, which, consequently, is related to damage to proteins, lipids, and DNA. Among the harmful effects of MPH, studies also demonstrate its ability to induce inflammation as well as alter the apoptosis pathway. It is important to highlight that age, treatment time, administration route, and dose are factors that can influence MPH effects. However, young animals seem to be more susceptible to damage caused by MPH. It is possible that changes in mitochondrial function and markers of status oxidative, apoptosis and inflammation may be exerting important mechanisms associated with MPH toxicity and, therefore, the unrestricted use of this drug can cause brain damage.
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Emmerzaal TL, Nijkamp G, Veldic M, Rahman S, Andreazza AC, Morava E, Rodenburg RJ, Kozicz T. Effect of neuropsychiatric medications on mitochondrial function: For better or for worse. Neurosci Biobehav Rev 2021; 127:555-571. [PMID: 34000348 DOI: 10.1016/j.neubiorev.2021.05.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/12/2021] [Accepted: 05/04/2021] [Indexed: 01/22/2023]
Abstract
Individuals with mitochondrial disease often present with psychopathological comorbidity, and mitochondrial dysfunction has been proposed as the underlying pathobiology in various psychiatric disorders. Several studies have suggested that medications used to treat neuropsychiatric disorders could directly influence mitochondrial function. This review provides a comprehensive overview of the effect of these medications on mitochondrial function. We collected preclinical information on six major groups of antidepressants and other neuropsychiatric medications and found that the majority of these medications either positively influenced mitochondrial function or showed mixed effects. Only amitriptyline, escitalopram, and haloperidol were identified as having exclusively adverse effects on mitochondrial function. In the absence of formal clinical trials, and until such trials are completed, the data from preclinical studies reported and discussed here could inform medication prescribing practices for individuals with psychopathology and impaired mitochondrial function in the underlying pathology.
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Affiliation(s)
- Tim L Emmerzaal
- Radboud University Medical Center, Donders Institute for Brain Cognition and Behaviour, Department of Medical Imaging, Anatomy, Nijmegen, The Netherlands; Mayo Clinic, Department of Clinical Genomics, Rochester, MN, USA
| | - Gerben Nijkamp
- Radboud University Medical Center, Donders Institute for Brain Cognition and Behaviour, Department of Medical Imaging, Anatomy, Nijmegen, The Netherlands
| | - Marin Veldic
- Mayo Clinic, Department of Psychiatry, Rochester, MN, USA
| | - Shamima Rahman
- Mitochondrial Research Group, UCL Great Ormond Street Institute of Child Health, London, United Kingdom; Metabolic Unit, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Ana Cristina Andreazza
- University of Toronto, Temerty Faculty of Medicine, Department of Pharmacology & Toxicology and Psychiatry, Toronto, Canada
| | - Eva Morava
- Mayo Clinic, Department of Clinical Genomics, Rochester, MN, USA; Mayo Clinic, Department of Laboratory Medicine and Pathology, Rochester, MN, USA
| | - Richard J Rodenburg
- Radboud Center for Mitochondrial Medicine, Translational Metabolic Laboratory, Department of Pediatrics, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Tamas Kozicz
- Radboud University Medical Center, Donders Institute for Brain Cognition and Behaviour, Department of Medical Imaging, Anatomy, Nijmegen, The Netherlands; Mayo Clinic, Department of Clinical Genomics, Rochester, MN, USA; Mayo Clinic, Department of Biochemistry and Molecular Biology, Rochester, MN, USA.
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Freddo N, Soares SM, Fortuna M, Pompermaier A, Varela ACC, Maffi VC, Mozzato MT, de Alcantara Barcellos HH, Koakoski G, Barcellos LJG, Rossato-Grando LG. Stimulants cocktail: Methylphenidate plus caffeine impairs memory and cognition and alters mitochondrial and oxidative status. Prog Neuropsychopharmacol Biol Psychiatry 2021; 106:110069. [PMID: 32800866 DOI: 10.1016/j.pnpbp.2020.110069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/05/2020] [Accepted: 08/07/2020] [Indexed: 11/28/2022]
Abstract
Methylphenidate (MPH) is a psychostimulant widely misused to increase wakefulness by drivers and students. Also, MPH can be found in dietary supplements in a clandestine manner aiming to burst performance of physical exercise practitioners. The abusive use of high doses of caffeine (CAF) in these contexts is equally already known. Here, we demonstrate the behavioral, oxidative and mitochondrial effects after acute exposure to high doses of MPH (80 mg/L) and CAF (150 mg/L), alone or associated (80 mg/L + 150 mg/L, respectively). We used zebrafish as animal model due to its high translational relevance. We evaluated the behavioral effects using the Novel Tank Test (NTT), Social Preference Test (SPT) and Y-maze Task and analyzed biomarkers of oxidative stress and activity of mitochondrial respiratory chain complexes. MPH alone induced antisocial behavior. MPH inhibited lipid peroxidation. The association of MPH + CAF presented memory impairment and anxiogenic behavior. In oxidative status, it inhibited lipid peroxidation, increased protein carbonylation and mitochondrial complex II, III and IV activity. Our results demonstrate that MPH and CAF alone negatively impact the typical behavioral of zebrafish. When associated, changes in cognition, memory, oxidative and mitochondrial status are more relevant.
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Affiliation(s)
- Natália Freddo
- Programa de Pós-graduação em Bioexperimentação, Universidade de Passo Fundo, Passo Fundo, Rio Grande do Sul, Brazil
| | - Suelen Mendonça Soares
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil
| | - Milena Fortuna
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil
| | - Aline Pompermaier
- Programa de Pós-graduação em Bioexperimentação, Universidade de Passo Fundo, Passo Fundo, Rio Grande do Sul, Brazil
| | | | - Victoria Costa Maffi
- Curso de Medicina Veterinária, Universidade de Passo Fundo, Passo Fundo, Rio Grande do Sul, Brazil
| | - Mateus Timbola Mozzato
- Curso de Medicina Veterinária, Universidade de Passo Fundo, Passo Fundo, Rio Grande do Sul, Brazil
| | - Heloísa Helena de Alcantara Barcellos
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil; Curso de Medicina Veterinária, Universidade de Passo Fundo, Passo Fundo, Rio Grande do Sul, Brazil
| | - Gessi Koakoski
- Curso de Medicina Veterinária, Universidade de Passo Fundo, Passo Fundo, Rio Grande do Sul, Brazil
| | - Leonardo José Gil Barcellos
- Programa de Pós-graduação em Bioexperimentação, Universidade de Passo Fundo, Passo Fundo, Rio Grande do Sul, Brazil; Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, Brazil; Curso de Medicina Veterinária, Universidade de Passo Fundo, Passo Fundo, Rio Grande do Sul, Brazil
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Öğütlü H, Esin İS, Erdem HB, Tatar A, Dursun OB. Mitochondrial DNA copy number may be associated with attention deficit/hyperactivity disorder severity in treatment: a one-year follow-up study. Int J Psychiatry Clin Pract 2021; 25:37-42. [PMID: 33555215 DOI: 10.1080/13651501.2021.1879158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVE Studies on etiopathogenesis of attention deficit/hyperactivity disorder (ADHD) are increasingly focussing on mitochondrial dysfunction. Children diagnosed with ADHD who had significantly higher mitochondrial DNA (mtDNA) copy numbers than healthy children in our first study were re-examined in 1-year follow-up to investigate effects of severity and treatment of ADHD on mtDNA. METHODS Twenty-eight patients who participated in previous study were included in this follow-up study. Patients were equally divided into two groups according to whether they had been receiving treatment. Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version, and Conners Parent Rating Scale (CPRS) were used. Polymerase chain reaction was performed. RESULTS Means of the first and second mtDNA copy were similar in all patients. mtDNA copy numbers did not change between two measurements in treated and non-treated groups. There was a correlation between CPRS ADHD index and inattention scores and mtDNA copy number in treated group. mtDNA copy number did not change in patients with ADHD over a period of 1 year regardless of treatment. CONCLUSIONS There may be a relationship between decreased ADHD severity with treatment and positive effects of mitochondrial functions. Mitochondrial dysfunction may play a role in pathophysiology of ADHD.KEY POINTSThis was the first study to follow up ADHD patients in order to investigate mitochondrial dysfunction by measuring mtDNA copy numbers 1 year after the initial measurements.mtDNA copy number, one of the best markers of mitochondrial dysfunction, did not change in ADHD patients over a period of 1 year regardless of treatment.Mitochondrial dysfunction may play a role in the pathophysiology of ADHD, where it may be involved with or without treatment.In the treated group, there was an association between decreased ADHD severity and reduced mtDNA copy numbers.There may be a relationship between decreased ADHD severity with treatment and the positive effects of mitochondrial functions.
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Affiliation(s)
- Hakan Öğütlü
- Department of Child and Adolescent Psychiatry, Ankara City Hospital, Ankara, Turkey
| | - İbrahim Selçuk Esin
- Department of Child and Adolescent Psychiatry, Ataturk University Faculty of Medicine, Erzurum, Turkey
| | - Haktan Bağış Erdem
- Department of Medical Genetic, Dr. Abdurrahman Yurtaslan Ankara Oncology Training and Research Hospital, Ankara, Turkey
| | - Abdülgani Tatar
- Department of Medical Genetic, Ataturk University Faculty of Medicine, Erzurum, Turkey
| | - Onur Burak Dursun
- Department of Child and Adolescent Psychiatry, University of Health Sciences Faculty of Medicine, Trabzon, Turkey
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Ebrahimzadeh A, Moghadam SY, Rahimi H, Motaghinejad M, Motevalian M, Safari S, Mesrabadi MA. Crocin acts as a neuroprotective mediator against methylphenidate-induced neurobehavioral and neurochemical sequelae: Possible role of the CREB-BDNF signaling pathway. Acta Neurobiol Exp (Wars) 2020. [DOI: 10.21307/ane-2019-033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Holper L, Ben-Shachar D, Mann JJ. Psychotropic and neurological medication effects on mitochondrial complex I and IV in rodent models. Eur Neuropsychopharmacol 2019; 29:986-1002. [PMID: 31320210 DOI: 10.1016/j.euroneuro.2019.06.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 04/29/2019] [Accepted: 06/26/2019] [Indexed: 12/12/2022]
Abstract
Mitochondrial complex I (NADH-dehydrogenase) and complex IV (cytochrome-c-oxidase) are reported to be affected by drugs used to treat psychiatric or neurodegenerative diseases, including antidepressants, antipsychotics, anxiolytics, mood stabilizers, stimulants, antidementia, and antiparkinsonian drugs. We conducted meta-analyses examining the effects of each drug category on complex I and IV. The electronic databases Pubmed, EMBASE, CENTRAL, and Google Scholar were searched for studies published between 1970 and 2018. Of 3105 screened studies, 68 articles covering 53 drugs were included in the meta-analyses. All studies assessed complex I and IV in rodent brain at the level of enzyme activity. Results revealed that selected antidepressants increase or decrease complex I and IV, antipsychotics and stimulants decrease complex I but increase complex IV, whereas anxiolytics, mood stabilizers, antidementia, and antiparkinsonian drugs preserve or even enhance both complex I and IV. Potential contributions to the drug effects were found to be related to the drugs' neurotransmitter receptor profiles with adrenergic (α1B), dopaminergic (D1/2), glutaminergic (NMDA1,3), histaminergic (H1), muscarinic (M1,3), opioid (OP1-3), serotonergic (5-HT2A, 5-HT2C, 5-HT3A) and sigma (σ1) receptors having the greatest effects. The findings are discussed in relation to pharmacological mechanisms of action that might have relevance for clinical and research applications.
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Affiliation(s)
- L Holper
- Department of Psychiatry, Psychotherapy, and Psychosomatics, University Hospital of Psychiatry Zurich, University of Zurich, 8032 Zurich, Switzerland.
| | - D Ben-Shachar
- Laboratory of Psychobiology, Department of Psychiatry, Rambam Health Care Campus, Rappaport Faculty of Medicine, Technion IIT, Haifa, Israel
| | - J J Mann
- Division of Molecular Imaging and Neuropathology, Columbia University and New York State Psychiatric Institute, New York, USA
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Salehi P, Shahmirzadi ZY, Mirrezaei FS, Shirvani Boushehri F, Mayahi F, Songhori M, Abofazeli M, Motaghinejad M, Safari S. A hypothetic role of minocycline as a neuroprotective agent against methylphenidate-induced neuronal mitochondrial dysfunction and tau protein hyper-phosphorylation: Possible role of PI3/Akt/GSK3β signaling pathway. Med Hypotheses 2019; 128:6-10. [PMID: 31203911 DOI: 10.1016/j.mehy.2019.04.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 04/14/2019] [Accepted: 04/23/2019] [Indexed: 02/08/2023]
Abstract
The underlining mechanism in neural mitochondrial dysfunction and consequences neurotoxicity, and cognitive behavior after methylphenidate (MPH) prolonged uses is unclear and proposing of therapeutic approaches for treatment of these types of neurotoxicity is one of the main goals of scientist in this manner. MPH-induced mitochondrial dysfunction in neural cells caused induction of oxidative stress, apoptosis, inflammation and cognition impairment, which leads to neurotoxicity, was reported previously but role of key neural cells proteins and involved signaling pathway in this manner remained indeterminate. Tau protein aggregation is a biomarker for mitochondrial dysfunction, neurodegenerative event and cognition impairment. Tau aggregation occur by stimulation effects of Glycogen synthase kinase-3(GSK3β) and phosphatidylinositol 3-kinase (PI3K) which activates protein kinase B(Akt) and causes inhibition of phosphorylation(activation) of GSK3β, thus Akt activation can cause inhibition of tau aggregation (hyper-phosphorylation). Management of mentioned MPH-induced mitochondrial dysfunction and consequences of neurotoxicity, and cognitive behavior through a new generation neuroprotective combination, based on modulation of disturbed in Akt function and inhibition of GSK3β and tau hyper-phosphorylation can be a prefect therapeutic interventions. Therefore, finding, introduction and development of new neuroprotective properties and explanation of their effects with potential capacity for modulation of tau hyper-phosphorylation via PI3/Akt/GSK signaling pathway is necessitated. During recent years, using new neuroprotective compounds with therapeutic probability for treatment of psychostimulant-induced mitochondrial dysfunction, neurotoxicity and cognitive malicious effects have been amazingly increased. Many previous studies have reported the neuroprotective roles of minocycline (a broad-spectrum and long-acting antibiotic) in multiple neurodegenerative events and diseases in animal model. But the role of neuroprotective effects of this agent against MPH induced mitochondrial dysfunction, neurotoxicity and cognitive malicious and also role of tau hyper-phosphorylation by modulation of PI3/Akt/GSK signaling pathway in this manner remain unknown. Thus we suggested and theorized that by using minocycline in MPH addicted subject, it would provide neuroprotection against MPH-induced mitochondrial dysfunction, neurotoxicity and cognitive malicious. Also we hypothesized that minocycline, via modulation of PI3/Akt/GSK and inhibition of tau hyper-phosphorylation, can inhibit MPH-induced mitochondrial dysfunction, neurotoxicity and cognitive malicious. In this article, we tried to discuss our hypothesis regarding the possible role of minocycline, as a powerful neuroprotective agent, and also role of tau hyper-phosphorylation related to PI3/Akt/GSK signaling pathway in treatment of MPH-induced mitochondrial dysfunction, neurotoxicity and cognitive disturbance.
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Affiliation(s)
- Pegah Salehi
- Research Center for Addiction and Risky Behaviors (ReCARB), Iran Psychiatric Center, Iran University of Medical Sciences, Tehran, Iran
| | - Zhara Yaraei Shahmirzadi
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University (IUAPS), Tehran, Iran
| | - Fatemeh Sadat Mirrezaei
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University (IUAPS), Tehran, Iran
| | - Farima Shirvani Boushehri
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University (IUAPS), Tehran, Iran
| | - Fatemeh Mayahi
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University (IUAPS), Tehran, Iran
| | - Mojtaba Songhori
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University (IUAPS), Tehran, Iran
| | - Maryam Abofazeli
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University (IUAPS), Tehran, Iran
| | - Majid Motaghinejad
- Research Center for Addiction and Risky Behaviors (ReCARB), Iran Psychiatric Center, Iran University of Medical Sciences, Tehran, Iran.
| | - Sepideh Safari
- Razi Drug Research Center, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
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Schmitz F, Pierozan P, Biasibetti-Brendler H, Ferreira FS, Dos Santos Petry F, Trindade VMT, Pessoa-Pureur R, Wyse ATS. Methylphenidate disrupts cytoskeletal homeostasis and reduces membrane-associated lipid content in juvenile rat hippocampus. Metab Brain Dis 2018; 33:693-704. [PMID: 29288365 DOI: 10.1007/s11011-017-0177-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Accepted: 12/25/2017] [Indexed: 12/16/2022]
Abstract
Although methylphenidate (MPH) is ubiquitously prescribed to children and adolescents, the consequences of chronic utilization of this psychostimulant are poorly understood. In this study, we investigated the effects of MPH on cytoskeletal homeostasis and lipid content in rat hippocampus. Wistar rats received intraperitoneal injections of MPH (2.0 mg/kg) or saline solution (controls), once a day, from the 15th to the 44th day of age. Results showed that MPH provoked hypophosphorylation of glial fibrillary acidic protein (GFAP) and reduced its immunocontent. Middle and high molecular weight neurofilament subunits (NF-M, NF-H) were hypophosphorylated by MPH on KSP repeat tail domains, while NFL, NFM and NFH immunocontents were not altered. MPH increased protein phosphatase 1 (PP1) and 2A (PP2A) immunocontents. MPH also decreased the total content of ganglioside and phospholipid, as well as the main brain gangliosides (GM1, GD1a, and GD1b) and the major brain phospholipids (sphingomyelin, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and phosphatidylserine). Total cholesterol content was also reduced in the hippocampi of juvenile rats treated with MPH. These results provide evidence that disruptions of cytoskeletal and lipid homeostasis in hippocampus of juvenile rats are triggers by chronic MPH treatment and present a new basis for understanding the effects and consequences associated with chronic use of this psychostimulant during the development of the central nervous system.
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Affiliation(s)
- Felipe Schmitz
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Paula Pierozan
- Laboratório de Neuroproteção e Doenças Metabólicas, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, CEP 90035-003, Brazil
| | - Helena Biasibetti-Brendler
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Fernanda Silva Ferreira
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Fernanda Dos Santos Petry
- Laboratório de Bioquímica e Biologia Celular de Lipídios, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Vera Maria Treis Trindade
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
- Laboratório de Bioquímica e Biologia Celular de Lipídios, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Regina Pessoa-Pureur
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
- Laboratório do Citoesqueleto, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Angela T S Wyse
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
- Laboratório de Neuroproteção e Doenças Metabólicas, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, CEP 90035-003, Brazil.
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Methylphenidate clinically oral doses improved brain and heart glutathione redox status and evoked renal and cardiac tissue injury in rats. Biomed Pharmacother 2018; 100:551-563. [PMID: 29482048 DOI: 10.1016/j.biopha.2018.02.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Revised: 02/02/2018] [Accepted: 02/03/2018] [Indexed: 01/20/2023] Open
Abstract
Methylphenidate (MPH) is a first-line stimulant drug to treat attention deficit hyperactivity disorder (ADHD). Overdiagnosis of ADHD and MPH abuse lead to serious concerns about the possible long-term adverse consequences of MPH in healthy children and adolescents. We aimed to evaluate MPH effects in adolescent male Wistar rats (postnatal day 40) using an oral dose scheme (2 daily MPH doses 5 mg/kg in a 5% sucrose solution, 5 h apart, for 7 days) that mimics the therapeutic doses given to human adolescents. Twenty-four hours after the last MPH administration, rats were sacrificed and brain areas [cerebellum, prefrontal cortex (PFC), hippocampus, and striatum], peripheral organs (liver, heart, and kidneys), and blood were collected for biochemical and histological analysis. MPH treatment did not alter rats' body temperature or weight, neither food or water intake throughout the experiment. The ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) significantly increased in the PFC and hippocampus of MPH-treated rats, meanwhile protein carbonylation remained unchanged in the brain. In the heart, the GSH/GSSG ratio and GSH levels were significantly increased, with decreased GSSG, while histology revealed significant damage, namely interstitial edema, vascular congestion, and presence of a fibrin-like material in the interstitial space. In the kidneys, MPH treatment resulted in extensive necrotic areas with cellular disorganization and cell infiltration, and immunohistochemistry analysis revealed a marked activation of nuclear factor-ĸB. This study showed that clinically relevant oral MPH doses improve the GSH redox status in the brain and heart, but evoke heart and kidney tissue damage to adolescent rats.
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Bottelier MA, Schrantee A, Ferguson B, Tamminga HGH, Bouziane C, Kooij JJS, de Ruiter MB, Reneman L. Age-dependent effects of acute methylphenidate on amygdala reactivity in stimulant treatment-naive patients with Attention Deficit/Hyperactivity Disorder. Psychiatry Res Neuroimaging 2017; 269:36-42. [PMID: 28938219 DOI: 10.1016/j.pscychresns.2017.09.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 09/06/2017] [Accepted: 09/10/2017] [Indexed: 11/18/2022]
Abstract
In the present study, we investigate whether methylphenidate (MPH) affects emotional processing and whether this effect is modulated by age. We measured amygdala reactivity with functional Magnetic Resonance Imaging (fMRI) during processing of angry and fearful facial expressions in male stimulant treatment-naive patients with ADHD (N = 35 boys; N = 46 men) and 23 healthy control subjects (N = 11 boys; N = 12 men). In ADHD patients, we also measured amygdala reactivity 90min after an acute oral challenge with MPH (0.5mg/kg). Mean amygdala reactivity was analyzed for all subjects using a repeated measures analysis of variance (ANOVA). Whole-brain maps were analyzed for the patients only. At baseline, we found a age*diagnosis effect approaching significance (p = 0.05) in the right amygdala due to lower reactivity in children with Attention Deficit/Hyperactivity Disorder (ADHD) vs. controls (-31%), but higher reactivity in adults with ADHD vs. controls (+31%). MPH significantly reduced right amygdala reactivity in all patients, resulting in further reductions in children. In the left amygdala, reduction of amygdala reactivity was confined to adult ADHD patients whereas there was no change in children with ADHD. MPH-induced decrease of amygdala reactivity in adults might be a promising avenue for managing emotional dysregulation when replicated for chronic MPH treatment.
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Affiliation(s)
- Marco A Bottelier
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Department of Child, and Adolescent Psychiatry, Triversum, Alkmaar, The Netherlands
| | - Anouk Schrantee
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Amsterdam Brain and Cognition, University of Amsterdam, Amsterdam, The Netherlands
| | - Bart Ferguson
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Brain Center Rudolph Magnus, Department of Psychiatry, University Medical Center, Utrecht, The Netherlands
| | - Hyke G H Tamminga
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Dutch Autism and ADHD research center, University of Amsterdam, Amsterdam, The Netherlands
| | - Cheima Bouziane
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - J J Sandra Kooij
- PsyQ, psycho-medical programs, Expertise Center Adult ADHD, Den Haag, The Netherlands
| | - Michiel B de Ruiter
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Division of Psychosocial Research and Epidemiology, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Liesbeth Reneman
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Amsterdam Brain and Cognition, University of Amsterdam, Amsterdam, The Netherlands.
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12
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Methylphenidate effects in the young brain: friend or foe? Int J Dev Neurosci 2017; 60:34-47. [PMID: 28412445 DOI: 10.1016/j.ijdevneu.2017.04.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 03/07/2017] [Accepted: 04/06/2017] [Indexed: 01/17/2023] Open
Abstract
Attention deficit hyperactivity disorder (ADHD) is one of the most prevalent neuropsychiatry disorders in children and adolescents, and methylphenidate (MPH) is a first-line stimulant drug available worldwide for its treatment. Despite the proven therapeutic efficacy, concerns have been raised regarding the possible consequences of chronic MPH exposure during childhood and adolescence. Disturbances in the neurodevelopment at these crucial stages are major concerns given the unknown future life consequences. This review is focused on the long-term adverse effects of MPH to the brain biochemistry. Reports conducted with young and/or adolescent animals and studies with humans are reviewed in the context of long-term consequences after early life-exposure. MPH pharmacokinetics is also reviewed as there are differences among laboratory animals and humans that may be relevant to extrapolate the findings. Studies reveal that exposure to MPH in laboratory animals during young and/or adolescent ages can impact the brain, but the outcomes are dependent on MPH dose, treatment period, and animal's age. Importantly, the female sex is largely overlooked in both animal and human studies. Unfortunately, human reports that evaluate adults following adolescent or child exposure to MPH are very scarce. In general, human data indicates that MPH is generally safe, although it can promote several brain changes in early ages. Even so, there is a lack of long course patient evaluation to clearly establish whether MPH-induced changes are friendly or foe to the brain and more human studies are needed to assess the adult brain changes that arise from early MPH treatment.
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13
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Schmitz F, Pierozan P, Rodrigues AF, Biasibetti H, Grings M, Zanotto B, Coelho DM, Vargas CR, Leipnitz G, Wyse ATS. Methylphenidate Decreases ATP Levels and Impairs Glutamate Uptake and Na +,K +-ATPase Activity in Juvenile Rat Hippocampus. Mol Neurobiol 2016; 54:7796-7807. [PMID: 27844288 DOI: 10.1007/s12035-016-0289-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 11/02/2016] [Indexed: 01/05/2023]
Abstract
The study of the long-term neurological consequences of early exposure with methylphenidate (MPH) is very important since this psychostimulant has been widely misused by children and adolescents who do not meet full diagnostic criteria for ADHD. The aim of this study was to examine the effect of early chronic exposure with MPH on amino acids profile, glutamatergic and Na+,K+-ATPase homeostasis, as well as redox and energy status in the hippocampus of juvenile rats. Wistar male rats received intraperitoneal injections of MPH (2.0 mg/kg) or saline solution (controls), once a day, from the 15th to the 45th day of age. Results showed that MPH altered amino acid profile in the hippocampus, decreasing glutamine levels. Glutamate uptake and Na+,K+-ATPase activity were decreased after chronic MPH exposure in the hippocampus of rats. No changes were observed in the immunocontents of glutamate transporters (GLAST and GLT-1), and catalytic subunits of Na+,K+-ATPase (α1, α2, and α3), as well as redox status. Moreover, MPH provoked a decrease in ATP levels in the hippocampus of chronically exposed rats, while citrate synthase, succinate dehydrogenase, respiratory chain complexes activities (II, II-III, and IV), as well as mitochondrial mass and mitochondrial membrane potential were not altered. Taken together, our results suggest that chronic MPH exposure at early age impairs glutamate uptake and Na+,K+-ATPase activity probably by decreasing in ATP levels observed in rat hippocampus.
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Affiliation(s)
- Felipe Schmitz
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Paula Pierozan
- Laboratório de Neuroproteção e Doenças Metabólicas, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - André F Rodrigues
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Helena Biasibetti
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Mateus Grings
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Bruna Zanotto
- Laboratório de Neuroproteção e Doenças Metabólicas, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Daniella M Coelho
- Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil
| | - Carmen R Vargas
- Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil
| | - Guilhian Leipnitz
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.,Laboratório de Neuroproteção e Doenças Metabólicas, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Angela T S Wyse
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. .,Laboratório de Neuroproteção e Doenças Metabólicas, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. .,Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, CEP 90035-003, Brazil.
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Methylphenidate treatment causes oxidative stress and alters energetic metabolism in an animal model of attention-deficit hyperactivity disorder. Acta Neuropsychiatr 2014; 26:96-103. [PMID: 24855887 DOI: 10.1017/neu.2013.35] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVES To evaluate oxidative damage through the thiobarbituric acid-reactive species (TBARS) and protein carbonyl groups; antioxidant enzymatic system - superoxide dismutase (SOD) and catalase (CAT); and energetic metabolism in the brain of spontaneously hypertensive adult rats (SHR) after both acute and chronic treatment with methylphenidate hydrochloride (MPH). METHODS Adult (60 days old) SHRs were treated during 28 days (chronic treatment), or 1 day (acute treatment). The rats received one i.p. injection per day of either saline or MPH (2 mg/kg). Two hours after the last injection, oxidative damage parameters and energetic metabolism in the cerebellum, prefrontal cortex, hippocampus, striatum and cortex were evaluated. RESULTS We observed that both acute and/or chronic treatment increased TBARS and carbonyl groups, and decreased SOD and CAT activities in many of the brain structures evaluated. Regarding the energetic metabolism evaluation, the acute and chronic treatment altered the energetic metabolism in many of the brain structures evaluated. CONCLUSION We observed that both acute and chronic use of methylphenidate hydrochloride (MPH) in adult spontaneously hypertensive rats (SHRs) was associated with increased oxidative stress and energetic metabolism alterations. These data also reinforce the importance of the SHR animal model in further studies regarding MPH.
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15
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Gonçalves J, Baptista S, Silva AP. Psychostimulants and brain dysfunction: a review of the relevant neurotoxic effects. Neuropharmacology 2014; 87:135-49. [PMID: 24440369 DOI: 10.1016/j.neuropharm.2014.01.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 12/18/2013] [Accepted: 01/06/2014] [Indexed: 12/21/2022]
Abstract
Psychostimulants abuse is a major public concern because is associated with serious health complications, including devastating consequences on the central nervous system (CNS). The neurotoxic effects of these drugs have been extensively studied. Nevertheless, numerous questions and uncertainties remain in our understanding of these toxic events. Thus, the purpose of the present manuscript is to review cellular and molecular mechanisms that might be responsible for brain dysfunction induced by psychostimulants. Topics reviewed include some classical aspects of neurotoxicity, such as monoaminergic system and mitochondrial dysfunction, oxidative stress, excitotoxicity and hyperthermia. Moreover, recent literature has suggested new phenomena regarding the toxic effects of psychostimulants. Thus, we also reviewed the impact of these drugs on neuroinflammatory response, blood-brain barrier (BBB) function and neurogenesis. Assessing the relative importance of these mechanisms on psychostimulants-induced brain dysfunction presents an exciting challenge for future research efforts. This article is part of the Special Issue entitled 'CNS Stimulants'.
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Affiliation(s)
- Joana Gonçalves
- Laboratory of Pharmacology and Experimental Therapeutics, Institute for Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548 Coimbra Portugal
| | - Sofia Baptista
- Laboratory of Pharmacology and Experimental Therapeutics, Institute for Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548 Coimbra Portugal
| | - Ana Paula Silva
- Laboratory of Pharmacology and Experimental Therapeutics, Institute for Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Azinhaga Santa Comba, Celas, 3000-548 Coimbra Portugal.
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16
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Methylphenidate treatment leads to abnormalities on krebs cycle enzymes in the brain of young and adult rats. Neurotox Res 2013; 24:251-7. [PMID: 23423652 DOI: 10.1007/s12640-013-9383-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 01/31/2013] [Accepted: 02/02/2013] [Indexed: 12/13/2022]
Abstract
Studies have shown a relationship between energy metabolism and methylphenidate (MPH); however, there are no studies evaluating the effects of MPH in Krebs cycle. So, we investigated if MPH treatment could alter the activity of citrate synthase (CS), malate dehydrogenase (MD), and isocitrate dehydrogenase (ID) in the brain of young and adult Wistar rats. Our results showed that MPH (2 and 10 mg/kg) reduced CS in the striatum and prefrontal cortex (PF), with MPH at all doses in the cerebellum and hippocampus after chronic treatment in young rats. In adult rats the CS was reduced in the cerebellum after acute treatment with MPH at all doses, and after chronic treatment in the PF and cerebellum with MPH (10 mg/kg), and in the hippocampus with MPH (2 and 10 mg/kg). The ID decreased in the hippocampus and striatum with MPH (2 and 10 mg/kg), and in the cortex (10 mg/kg) after acute treatment in young rats. In adult rats acute treatment with MPH (2 and 10 mg/kg) reduced ID in the cerebellum, and with MPH (10 mg/kg) in the cortex; chronic treatment with MPH (10 mg/kg) decreased ID in the PF; with MPH (2 and 10 mg/kg) in the cerebellum, and with MPH at all doses in the hippocampus. The MD did not alter. In conclusion, our results suggest that MPH can alter enzymes of Krebs cycle in brain areas involved with circuits related with attention deficit hyperactivity disorder; however, such effects depend on age of animal and treatment regime.
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Lempp T, Toennes SW, Wunder C, Russe OQ, Möser CV, Kynast KL, Freitag CM, Niederberger E. Altered gene expression in the prefrontal cortex of young rats induced by the ADHD drug atomoxetine. Prog Neuropsychopharmacol Biol Psychiatry 2013; 40:221-8. [PMID: 22960082 DOI: 10.1016/j.pnpbp.2012.08.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 08/23/2012] [Accepted: 08/23/2012] [Indexed: 01/03/2023]
Abstract
Atomoxetine (ATX), a selective norepinephrine reuptake inhibitor, is a non-stimulant approved for the treatment of attention deficit/hyperactivity disorder (ADHD). Little is known about the molecular basis for its therapeutic effect. The objective of this animal study was to determine alterations in gene expression patterns in the prefrontal cortex after long-term administration of atomoxetine. Rats were treated for 21 days during childhood and early adolescent stages of development with a once-daily oral application of 0.05 g/kg atomoxetine, which resulted in plasma levels similar to those described in children. A whole genome RNA-microarray of rat prefrontal cortical gene expression after administration of atomoxetine versus sterile water revealed an mRNA increase in 114 genes (≥2-fold) while 11 genes were down-regulated (≤0.5-fold). By applying quantitative real-time PCR (qRT-PCR) and Western Blot we confirmed a significant increase in the expression of GABA A receptor subunits as well as ubiquinol-cytochrome c reductase complex core protein 2 (Uqcrc2). SNAP-25 (synaptosomal-associated protein of 25 kDa), which is an ADHD candidate gene and an important vesicle protein involved in axonal growth, synaptic plasticity and regulation of neurotransmitter release was also significantly upregulated on RNA- and protein level after atomoxetine treatment. In summary, we could show that long-term treatment with the ADHD drug atomoxetine induces the regulation of several genes in the prefrontal cortex of young rats. Especially the increased expression of SNAP-25 and GABA-A receptor subunits may indicate additional active therapeutic mechanisms for atomoxetine.
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Affiliation(s)
- Thomas Lempp
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Goethe University Hospital Frankfurt, Deutschordenstrasse 50, 60528 Frankfurt am Main, Germany
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