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Treatment Options for Motor and Non-Motor Symptoms of Parkinson's Disease. Biomolecules 2021; 11:biom11040612. [PMID: 33924103 PMCID: PMC8074325 DOI: 10.3390/biom11040612] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 03/29/2021] [Accepted: 04/15/2021] [Indexed: 12/11/2022] Open
Abstract
Parkinson’s disease (PD) usually presents in older adults and typically has both motor and non-motor dysfunctions. PD is a progressive neurodegenerative disorder resulting from dopaminergic neuronal cell loss in the mid-brain substantia nigra pars compacta region. Outlined here is an integrative medicine and health strategy that highlights five treatment options for people with Parkinson’s (PwP): rehabilitate, therapy, restorative, maintenance, and surgery. Rehabilitating begins following the diagnosis and throughout any additional treatment processes, especially vis-à-vis consulting with physical, occupational, and/or speech pathology therapist(s). Therapy uses daily administration of either the dopamine precursor levodopa (with carbidopa) or a dopamine agonist, compounds that preserve residual dopamine, and other specific motor/non-motor-related compounds. Restorative uses strenuous aerobic exercise programs that can be neuroprotective. Maintenance uses complementary and alternative medicine substances that potentially support and protect the brain microenvironment. Finally, surgery, including deep brain stimulation, is pursued when PwP fail to respond positively to other treatment options. There is currently no cure for PD. In conclusion, the best strategy for treating PD is to hope to slow disorder progression and strive to achieve stability with neuroprotection. The ultimate goal of any management program is to improve the quality-of-life for a person with Parkinson’s disease.
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2
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Zhao DF, Fan YF, Wang FY, Hou FB, Gonzalez FJ, Li SY, Wang P, Xia YL, Ge GB, Yang L. Discovery and characterization of naturally occurring potent inhibitors of catechol- O-methyltransferase from herbal medicines. RSC Adv 2021; 11:10385-10392. [PMID: 35423513 PMCID: PMC8695704 DOI: 10.1039/d0ra10425f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/28/2021] [Indexed: 12/19/2022] Open
Abstract
Human catechol-O-methyltransferase (hCOMT) is considered a therapeutic target due to its crucial roles in the metabolic inactivation of endogenous neurotransmitters and xenobiotic drugs. There are nevertheless few safe and effective COMT inhibitors and there lacks a diversity in structure. To discover novel safe and effective hCOMT inhibitors from herbal products, in this study, 53 herbal products were collected and their inhibitory effects against hCOMT were investigated. Among them, Scutellariae radix (SR) displayed the most potent inhibitory effect on hCOMT with an IC50 value of 0.75 μg mL-1. To further determine specific chemicals as COMT inhibitors, an affinity ultrafiltration coupled with liquid chromatography-mass spectrometry method was developed and successfully applied to identify COMT inhibitors from SR extract. The results demonstrated that scutellarein 2, baicalein 9 and oroxylin A 12 were potent COMT inhibitors, showing a high binding index (>3) and very low IC50 values (32.9 ± 3.43 nM, 37.3 ± 4.32 nM and 18.3 ± 2.96 nM). The results of inhibition kinetics assays and docking simulations showed that compounds 2, 9 and 12 were potent competitive inhibitors against COMT-mediated 3-BTD methylation, and they could stably bind to the active site of COMT. These findings suggested that affinity ultrafiltration allows a rapid identification of natural COMT inhibitors from a complex plant extract matrix. Furthermore, scutellarein 2, baicalein 9 and oroxylin A 12 are potent inhibitors of hCOMT in SR, which could be used as promising lead compounds to develop more efficacious non-nitrocatechol COMT inhibitors for biomedical applications.
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Affiliation(s)
- Dong-Fang Zhao
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine Shanghai 201203 China
| | - Yu-Fan Fan
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine Shanghai 201203 China
| | - Fang-Yuan Wang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine Shanghai 201203 China
| | - Fan-Bin Hou
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine Shanghai 201203 China
| | - Frank J Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health Bethesda MD 20892 USA
| | - Shi-Yang Li
- Analytical Central Laboratory, Shenyang Harmony Health Medical Laboratory Co. Ltd Shenyang 210112 China
| | - Ping Wang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine Shanghai 201203 China
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health Bethesda MD 20892 USA
| | - Yang-Liu Xia
- School of Life Science and Medicine, Dalian University of Technology Panjin 124221 China
| | - Guang-Bo Ge
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine Shanghai 201203 China
| | - Ling Yang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine Shanghai 201203 China
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3
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Wang FY, Wang P, Zhao DF, Gonzalez FJ, Fan YF, Xia YL, Ge GB, Yang L. Analytical methodologies for sensing catechol- O-methyltransferase activity and their applications. J Pharm Anal 2021; 11:15-27. [PMID: 33717608 PMCID: PMC7930641 DOI: 10.1016/j.jpha.2020.03.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 03/21/2020] [Accepted: 03/30/2020] [Indexed: 01/02/2023] Open
Abstract
Mammalian catechol-O-methyltransferases (COMT) are an important class of conjugative enzymes, which play a key role in the metabolism and inactivation of catechol neurotransmitters, catechol estrogens and a wide range of endobiotics and xenobiotics that bear the catechol group. Currently, COMT inhibitors are used in combination with levodopa for the treatment of Parkinson's disease in clinical practice. The crucial role of COMT in human health has raised great interest in the development of more practical assays for highly selective and sensitive detection of COMT activity in real samples, as well as for rapid screening and characterization of COMT inhibitors as drug candidates. This review summarizes recent advances in analytical methodologies for sensing COMT activity and their applications. Several lists of biochemical assays for measuring COMT activity, including the probe substrates, along with their analytical conditions and kinetic parameters, are presented. Finally, the challenges and future perspectives in the field, such as visualization of COMT activity in vivo and in situ, are highlighted. Collectively, this review article overviews the practical assays for measuring COMT activities in complex biological samples, which will strongly facilitate the investigations on the relevance of COMT to human diseases and promote the discovery of COMT inhibitors via high-throughput screening.
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Affiliation(s)
- Fang-Yuan Wang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Ping Wang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Dong-Fang Zhao
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Frank J. Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Yu-Fan Fan
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Yang-Liu Xia
- School of Life Science and Medicine, Dalian University of Technology, Panjin, 124221, China
| | - Guang-Bo Ge
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Ling Yang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
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4
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Jalkanen A, Lassheikki V, Torsti T, Gharib E, Lehtonen M, Juvonen RO. Tissue and interspecies comparison of catechol- O-methyltransferase mediated catalysis of 6- O-methylation of esculetin to scopoletin and its inhibition by entacapone and tolcapone. Xenobiotica 2020; 51:268-278. [PMID: 33289420 DOI: 10.1080/00498254.2020.1853850] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Catechol-O-methyltransferase (COMT) methylates both endogenous and exogenous catechol compounds to inactive and safe metabolites. We first optimised conditions for a convenient and sensitive continuous fluorescence-based 6-O-methylation assay of esculetin, which we used for investigating the COMT activity in human, mouse, rat, dog, rabbit, and sheep liver cytosols and microsomes and in ten different rat tissues. Furthermore, we compared the inhibition potencies and mechanisms of two clinically used COMT inhibitors, entacapone and tolcapone, in these species. In most tissues, the COMT activity was at least three times higher in cytosol than in microsomes. In the rat, the highest COMT activity was found in the liver, followed by kidney, ileum, thymus, spleen, lung, pancreas, heart, brain, and finally, skeletal muscle. Entacapone and tolcapone were characterised as highly potent mixed type tight-binding inhibitors. The competitive inhibition type dominated over the uncompetitive inhibition with entacapone, whereas uncompetitive inhibition dominated with tolcapone. Rats, dogs, pigs, and sheep are high COMT activity species, in contrast to humans, mice, and rabbits; COMT activity is highest in the liver. Both entacapone and tolcapone are potent COMT inhibitors, but their inhibition mechanisms differ.
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Affiliation(s)
- Aaro Jalkanen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Veera Lassheikki
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Tommi Torsti
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Elham Gharib
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Marko Lehtonen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Risto O Juvonen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
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5
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Moskowitz S, Russ DW, Clark LA, Wages NP, Grooms DR, Woods AJ, Suhr J, Simon JE, O'Shea A, Criss CR, Fadda P, Clark BC. Is impaired dopaminergic function associated with mobility capacity in older adults? GeroScience 2020; 43:1383-1404. [PMID: 33236263 DOI: 10.1007/s11357-020-00303-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 11/18/2020] [Indexed: 01/14/2023] Open
Abstract
The capacity to move is essential for independence and declines with age. Slow movement speed, in particular, is strongly associated with negative health outcomes. Prior research on mobility (herein defined as movement slowness) and aging has largely focused on musculoskeletal mechanisms and processes. More recent work has provided growing evidence for a significant role of the nervous system in contributing to reduced mobility in older adults. In this article, we report four pieces of complementary evidence from behavioral, genetic, and neuroimaging experiments that, we believe, provide theoretical support for the assertion that the basal ganglia and its dopaminergic function are responsible, in part, for age-related reductions in mobility. We report four a posteriori findings from an existing dataset: (1) slower central activation of ballistic force development is associated with worse mobility among older adults; (2) older adults with the Val/Met intermediate catecholamine-O-methyl-transferase (COMT) genotype involved in dopamine degradation exhibit greater mobility than their homozygous counterparts; (3) there are moderate relationships between performance times from a series of lower and upper extremity tasks supporting the notion that movement speed in older adults is a trait-like attribute; and (4) there is a relationship of functional connectivity within the medial orbofrontal (mOFC) cortico-striatal network and measures of mobility, suggesting that a potential neural mechanism for impaired mobility with aging is the deterioration of the integrity of key regions within the mOFC cortico-striatal network. These findings align with recent basic and clinical science work suggesting that the basal ganglia and its dopaminergic function are mechanistically linked to age-related reductions in mobility capacity.
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Affiliation(s)
- Simon Moskowitz
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, 250 Irvine Hall, Athens, OH, 45701, USA
| | - David W Russ
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, 250 Irvine Hall, Athens, OH, 45701, USA.,School of Rehabilitation and Communication Sciences, Ohio University, Athens, OH, USA.,School of Physical Therapy & Rehabilitation Sciences, University of South Florida Morsani College of Medicine, Tampa, FL, USA
| | - Leatha A Clark
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, 250 Irvine Hall, Athens, OH, 45701, USA.,Department of Biomedical Sciences at Ohio University, Athens, OH, USA.,Department of Family Medicine at Ohio University, Athens, OH, USA
| | - Nathan P Wages
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, 250 Irvine Hall, Athens, OH, 45701, USA.,Department of Biomedical Sciences at Ohio University, Athens, OH, USA
| | - Dustin R Grooms
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, 250 Irvine Hall, Athens, OH, 45701, USA.,School of Applied Health and Wellness, Ohio University, Athens, OH, USA
| | - Adam J Woods
- Center for Cognitive Aging and Memory, Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA
| | - Julie Suhr
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, 250 Irvine Hall, Athens, OH, 45701, USA.,Department of Psychology, Ohio University, Athens, OH, USA
| | - Janet E Simon
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, 250 Irvine Hall, Athens, OH, 45701, USA.,School of Applied Health and Wellness, Ohio University, Athens, OH, USA
| | - Andrew O'Shea
- Center for Cognitive Aging and Memory, Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA
| | - Cody R Criss
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, 250 Irvine Hall, Athens, OH, 45701, USA
| | - Paolo Fadda
- Genomics Shared Resource-Comprehensive Cancer Center, The Ohio State University, Athens, OH, USA
| | - Brian C Clark
- Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, 250 Irvine Hall, Athens, OH, 45701, USA. .,Department of Biomedical Sciences at Ohio University, Athens, OH, USA. .,Division of Geriatric Medicine at Ohio University, Athens, OH, USA.
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6
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Hooten WM, Hu D, Cunningham JM, Black JL. Effect of catechol-O-methyltransferase (rs4680) single-nucleotide polymorphism on opioid-induced hyperalgesia in adults with chronic pain. Mol Pain 2020; 15:1744806919848929. [PMID: 31041874 PMCID: PMC6509985 DOI: 10.1177/1744806919848929] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The catechol-O-methyltransferase Val158Met polymorphism has been associated with alterations in pain perception, but the influence of the polymorphism on pain perception in patients with chronic pain receiving daily opioid therapy has not been previously reported. The primary aim of this study was to investigate the effects of the catechol-O-methyltransferase Val158Met polymorphism on heat pain perception in a cohort of adults receiving daily opioid therapy for chronic pain. Adults with chronic pain consecutively admitted to an outpatient pain rehabilitation program who met inclusion criteria and were receiving daily opioid therapy were recruited for study participation (N = 142). Individuals were genotyped for catechol-O-methyltransferase Val158Met (rs4680), and the polymorphism was analyzed using an additive and codominant genotype models. The distribution of the Val158Met genotypes was 25% for Val/Val, 41% for Val/Met and 34% for Met/Met (Hardy-Weinberg, P > 0.05). A main effect of genotype was observed for heat pain perception ( P = 0.028). Under the codominant model of allele effects, exploratory post hoc pairwise comparisons adjusted for morphine equivalent dose and pain catastrophizing demonstrated that individuals with the Val/Met genotype were hyperalgesic compared to individuals with the Val/Val ( P = 0.039) and Met/Met ( P = 0.023) genotypes. No significant association was observed between heat pain perception and genotype under the additive model of allele effects. Among patients with chronic pain who were receiving daily opioids, the Val/Met genotype was associated with hyperalgesia using a measure of heat pain perception that has been previously indicative of opioid-induced hyperalgesia in other heterogeneous samples of adults with chronic pain. This study contributes to the emerging understanding of how catechol-O-methyltransferase activity affects pain perception in the context of daily opioid use, and these findings may be useful in the design of future trials aimed at investigating the potential efficacy of ß-2 adrenergic receptor antagonism for opioid-induced hyperalgesia.
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Affiliation(s)
- W Michael Hooten
- 1 Department of Anesthesiology and Perioperative Medicine, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Danqing Hu
- 2 Department of Anesthesiology and Perioperative Medicine, Mayo Graduate School of Medicine, Rochester, MN, USA
| | - Julie M Cunningham
- 3 Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - John L Black
- 3 Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA
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7
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Winkler M, Geier M, Hanlon SP, Nidetzky B, Glieder A. Human Enzymes for Organic Synthesis. Angew Chem Int Ed Engl 2018; 57:13406-13423. [PMID: 29600541 PMCID: PMC6334177 DOI: 10.1002/anie.201800678] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Indexed: 02/06/2023]
Abstract
Human enzymes have been widely studied in various disciplines. The number of reactions taking place in the human body is vast, and so is the number of potential catalysts for synthesis. Herein, we focus on the application of human enzymes that catalyze chemical reactions in course of the metabolism of drugs and xenobiotics. Some of these reactions have been explored on the preparative scale. The major field of application of human enzymes is currently drug development, where they are applied for the synthesis of drug metabolites.
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Affiliation(s)
- Margit Winkler
- Institute for Molecular BiotechnologyGraz University of TechnologyPetersgasse 148010GrazAustria
- acib GmbHPetersgasse 148010GrazAustria
| | | | | | - Bernd Nidetzky
- acib GmbHPetersgasse 148010GrazAustria
- Institute of Biotechnology and Biochemical EngineeringGraz University of TechnologyPetersgasse 128010GrazAustria
| | - Anton Glieder
- Institute for Molecular BiotechnologyGraz University of TechnologyPetersgasse 148010GrazAustria
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8
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Zastrozhin MS, Brodyansky VM, Skryabin VY, Grishina EA, Ivashchenko DV, Ryzhikova KA, Savchenko LM, Kibitov AO, Bryun EA, Sychev DA. Pharmacodynamic genetic polymorphisms affect adverse drug reactions of haloperidol in patients with alcohol-use disorder. PHARMACOGENOMICS & PERSONALIZED MEDICINE 2017; 10:209-215. [PMID: 28744152 PMCID: PMC5511016 DOI: 10.2147/pgpm.s140700] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Background Antipsychotic action of haloperidol is due to blockade of D2 receptors in the mesolimbic dopamine pathway, while the adverse drug reactions are associated with striatal D2 receptor blockade. Contradictory data concerning the effects of genetic polymorphisms of genes encoding these receptors and associated structures (catechol-O-methyltransferase [COMT], glycine transporter and gene encoding the density of D2 receptors on the neuronal membrane) are described. Objective The objectives of this study were to evaluate the correlation between DRD2, SLC6A3 (DAT) and COMT genetic polymorphisms and to investigate their effect on the development of adverse drug reactions in patients with alcohol-use disorder who received haloperidol. Patients and methods The study included 64 male patients (average age 41.38 ± 10.14 years, median age 40 years, lower quintile [LQ] 35 years, upper quintile [UQ] 49 years). Bio-Rad CFX Manager™ software and “SNP-Screen” sets of “Syntol” (Russia) were used to determine polymorphisms rs4680, rs1800497, rs1124493, rs2242592, rs2298826 and rs2863170. In every “SNP-Screen” set, two allele-specific hybridizations were used, which allowed to determine two alleles of studied polymorphism separately on two fluorescence channels. Results Results of this study detected a statistically significant difference in the adverse drug reaction intensity in patients receiving haloperidol with genotypes 9/10 and 10/10 of polymorphic marker SLC6A3 rs28363170. In patients receiving haloperidol in tablets, the increases in the UKU Side-Effect Rating Scale (UKU) score of 9.96 ± 2.24 (10/10) versus 13 ± 2.37 (9/10; p < 0.001) and in the Simpson-Angus Scale (SAS) score of 5.04 ± 1.59 (10/10) versus 6.41 ± 1.33 (9/10; p = 0.006) were revealed. Conclusion Polymorphism of the SCL6A3 gene can affect the safety of haloperidol, and this should be taken into account during the choice of drug and its dosage regimen.
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Affiliation(s)
- Mikhail Sergeevich Zastrozhin
- Department of Addictology, Russian Medical Academy of Continuous Professional Education of the Ministry of Health of the Russian Federation, Moscow, Russia.,Moscow Research and Practical Centre on Addictions of the Moscow Department of Healthcare, Center for the Prevention of Dependent Behavior, Moscow, Russia
| | - Vadim Markovich Brodyansky
- Federal Medical Research Centre of Psychiatry and Addictology, Laboratory of Molecular Genetics, Moscow, Russia
| | - Valentin Yurievich Skryabin
- Moscow Research and Practical Centre on Addictions of the Moscow Department of Healthcare, Department of Addictology, Moscow, Russia
| | - Elena Anatolievna Grishina
- Russian Medical Academy of Continuous Professional Education of the Ministry of Health of the Russian Federation, Research Centre, Moscow, Russia
| | - Dmitry Vladimirovich Ivashchenko
- Russian Medical Academy of Continuous Professional Education of the Ministry of Health of the Russian Federation, Research Centre, Moscow, Russia
| | - Kristina Anatolievna Ryzhikova
- Russian Medical Academy of Continuous Professional Education of the Ministry of Health of the Russian Federation, Research Centre, Moscow, Russia
| | - Ludmila Mikhaylovna Savchenko
- Department of Addictology, Russian Medical Academy of Continuous Professional Education of the Ministry of Health of the Russian Federation, Moscow, Russia
| | - Alexander Olegovich Kibitov
- Federal Medical Research Centre of Psychiatry and Addictology, Laboratory of Molecular Genetics, Moscow, Russia
| | - Evgeny Alekseevich Bryun
- Department of Addictology, Russian Medical Academy of Continuous Professional Education of the Ministry of Health of the Russian Federation, Moscow, Russia.,Moscow Research and Practical Centre on Addictions of the Moscow Department of Healthcare, Department of Addictology, Moscow, Russia
| | - Dmitry Alekseevich Sychev
- Russian Medical Academy of Continuous Professional Education of the Ministry of Health of the Russian Federation, Department of Clinical Pharmacology and Therapy, Moscow, Russia
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9
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Ehler A, Benz J, Schlatter D, Rudolph MG. Mapping the conformational space accessible to catechol-O-methyltransferase. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2014; 70:2163-74. [PMID: 25084335 PMCID: PMC4118827 DOI: 10.1107/s1399004714012917] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 06/03/2014] [Indexed: 11/10/2022]
Abstract
Methylation catalysed by catechol-O-methyltransferase (COMT) is the main pathway of catechol neurotransmitter deactivation in the prefrontal cortex. Low levels of this class of neurotransmitters are held to be causative of diseases such as schizophrenia, depression and Parkinson's disease. Inhibition of COMT may increase neurotransmitter levels, thus offering a route for treatment. Structure-based drug design hitherto seems to be based on the closed enzyme conformation. Here, a set of apo, semi-holo, holo and Michaelis form crystal structures are described that define the conformational space available to COMT and that include likely intermediates along the catalytic pathway. Domain swaps and sizeable loop movements around the active site testify to the flexibility of this enzyme, rendering COMT a difficult drug target. The low affinity of the co-substrate S-adenosylmethionine and the large conformational changes involved during catalysis highlight significant energetic investment to achieve the closed conformation. Since each conformation of COMT is a bona fide target for inhibitors, other states than the closed conformation may be promising to address. Crystallographic data for an alternative avenue of COMT inhibition, i.e. locking of the apo state by an inhibitor, are presented. The set of COMT structures may prove to be useful for the development of novel classes of inhibitors.
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Affiliation(s)
- Andreas Ehler
- Molecular Design and Chemical Biology, F. Hoffmann-La Roche, Grenzacher Strasse 124, Basel, Switzerland
| | - Jörg Benz
- Molecular Design and Chemical Biology, F. Hoffmann-La Roche, Grenzacher Strasse 124, Basel, Switzerland
| | - Daniel Schlatter
- Molecular Design and Chemical Biology, F. Hoffmann-La Roche, Grenzacher Strasse 124, Basel, Switzerland
| | - Markus G. Rudolph
- Molecular Design and Chemical Biology, F. Hoffmann-La Roche, Grenzacher Strasse 124, Basel, Switzerland
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10
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Godar SC, Bortolato M. Gene-sex interactions in schizophrenia: focus on dopamine neurotransmission. Front Behav Neurosci 2014; 8:71. [PMID: 24639636 PMCID: PMC3944784 DOI: 10.3389/fnbeh.2014.00071] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 02/19/2014] [Indexed: 02/02/2023] Open
Abstract
Schizophrenia is a severe mental disorder, with a highly complex and heterogenous clinical presentation. Our current perspectives posit that the pathogenic mechanisms of this illness lie in complex arrays of gene × environment interactions. Furthermore, several findings indicate that males have a higher susceptibility for schizophrenia, with earlier age of onset and overall poorer clinical prognosis. Based on these premises, several authors have recently begun exploring the possibility that the greater schizophrenia vulnerability in males may reflect specific gene × sex (G×S) interactions. Our knowledge on such G×S interactions in schizophrenia is still rudimentary; nevertheless, the bulk of preclinical evidence suggests that the molecular mechanisms for such interactions are likely contributed by the neurobiological effects of sex steroids on dopamine (DA) neurotransmission. Accordingly, several recent studies suggest a gender-specific association of certain DAergic genes with schizophrenia. These G×S interactions have been particularly documented for catechol-O-methyltransferase (COMT) and monoamine oxidase (MAO), the main enzymes catalyzing DA metabolism. In the present review, we will outline the current evidence on the interactions of DA-related genes and sex-related factors, and discuss the potential molecular substrates that may mediate their cooperative actions in schizophrenia pathogenesis.
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Affiliation(s)
- Sean C Godar
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas Lawrence, KS, USA
| | - Marco Bortolato
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas Lawrence, KS, USA ; Consortium for Translational Research on Aggression and Drug Abuse, University of Kansas Lawrence, KS, USA
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11
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Ma Z, Liu H, Wu B. Structure-based drug design of catechol-O-methyltransferase inhibitors for CNS disorders. Br J Clin Pharmacol 2014; 77:410-20. [PMID: 23713800 PMCID: PMC3952716 DOI: 10.1111/bcp.12169] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 04/25/2013] [Indexed: 12/23/2022] Open
Abstract
Catechol-O-methyltransferase (COMT) is of great importance in pharmacology because it catalyzes the metabolism (methylation) of endogenous and xenobiotic catechols. Moreover, inhibition of COMT is the drug target in the management of central nervous system (CNS) disorders such as Parkinson's disease due to its role in regulation of the dopamine level in the brain. The X-ray crystal structures for COMT have been available since 1994. The active sites for cofactor and substrate/inhibitor binding are well resolved to an atomic level, providing valuable insights into the catalytic mechanisms as well as the role of magnesium ions in catalysis. Determination of how the substrates/inhibitors bind to the protein leads to a structure-based approach that has resulted in potent and selective inhibitors. This review focuses on the design of two types of inhibitors (nitrocatechol-type and bisubstrate inhibitors) for COMT using the protein structures.
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Affiliation(s)
- Zhiguo Ma
- Division of Pharmaceutics, College of Pharmacy, Jinan UniversityGuangzhou, Guangdong, China
| | - Hongming Liu
- Division of Pharmaceutics, College of Pharmacy, Jinan UniversityGuangzhou, Guangdong, China
| | - Baojian Wu
- Division of Pharmaceutics, College of Pharmacy, Jinan UniversityGuangzhou, Guangdong, China
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Meiser J, Weindl D, Hiller K. Complexity of dopamine metabolism. Cell Commun Signal 2013; 11:34. [PMID: 23683503 PMCID: PMC3693914 DOI: 10.1186/1478-811x-11-34] [Citation(s) in RCA: 418] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 05/10/2013] [Indexed: 01/15/2023] Open
Abstract
: Parkinson's disease (PD) coincides with a dramatic loss of dopaminergic neurons within the substantia nigra. A key player in the loss of dopaminergic neurons is oxidative stress. Dopamine (DA) metabolism itself is strongly linked to oxidative stress as its degradation generates reactive oxygen species (ROS) and DA oxidation can lead to endogenous neurotoxins whereas some DA derivatives show antioxidative effects. Therefore, DA metabolism is of special importance for neuronal redox-homeostasis and viability.In this review we highlight different aspects of dopamine metabolism in the context of PD and neurodegeneration. Since most reviews focus only on single aspects of the DA system, we will give a broader overview by looking at DA biosynthesis, sequestration, degradation and oxidation chemistry at the metabolic level, as well as at the transcriptional, translational and posttranslational regulation of all enzymes involved. This is followed by a short overview of cellular models currently used in PD research. Finally, we will address the topic from a medical point of view which directly aims to encounter PD.
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Affiliation(s)
- Johannes Meiser
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 7, avenue des Hauts-Fourneaux, L-4362 Esch-Belval, Luxembourg
| | - Daniel Weindl
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 7, avenue des Hauts-Fourneaux, L-4362 Esch-Belval, Luxembourg
| | - Karsten Hiller
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 7, avenue des Hauts-Fourneaux, L-4362 Esch-Belval, Luxembourg
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Qin X, Peng Q, Qin A, Chen Z, Lin L, Deng Y, Xie L, Xu J, Li H, Li T, Li S, Zhao J. Association of COMT Val158Met polymorphism and breast cancer risk: an updated meta-analysis. Diagn Pathol 2012; 7:136. [PMID: 23039364 PMCID: PMC3543196 DOI: 10.1186/1746-1596-7-136] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 10/05/2012] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Catechol-O-methyltransferase (COMT) is one of the most important enzymes involved in estrogen metabolism and its functional genetic polymorphisms may be associated with breast cancer (BC) risk. Many epidemiological studies have been conducted to explore the association between the COMT Val158Met polymorphism and breast cancer risk. However, the results remain inconclusive. In order to derive a more precise estimation of this relationship, a large meta-analysis was performed in this study. METHODS Systematic searches of the PubMed, Embase and Cochrane Library were performed. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate the strength of the association. RESULTS A total of 56 studies including 34,358 breast cancer cases and 45,429 controls were included. Overall, no significant associations between the COMT Val158Met polymorphism and breast cancer risk were found for LL versus HH, HL versus HH, LL versus HL, recessive model LL versus HL+HH, and dominant model LL+HL versus HH. In subgroup analysis by ethnicity, source of controls, and menopausal status, there was still no significant association detected in any of the genetic models. CONCLUSION Our meta-analysis results suggest that the COMT Val158Met polymorphism may not contribute to breast cancer susceptibility. VIRTUAL SLIDES The virtual slides(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs4806123577708417.
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Affiliation(s)
- Xue Qin
- Department of Clinical Laboratory, First Affiliated Hospital of Guangxi Medical University, Nanning 530021, Guangxi, China
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Association of functional COMT Val108/Met polymorphism with smoking cessation in a nicotine replacement therapy. J Neural Transm (Vienna) 2012; 119:1491-8. [PMID: 22695756 DOI: 10.1007/s00702-012-0841-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 05/27/2012] [Indexed: 10/28/2022]
Abstract
Nicotine replacement treatment (NRT) can be efficacious for smoking cessation, but used by only a minority of smokers in China. Pharmacogenetic matching may improve treatment outcomes for NRT in subgroups of smokers. We evaluated the efficacy and safety of sublingual nicotine tablets (SNT) for smoking cessation and the association of catechol-O-methyltransferase (COMT) genotype with efficacy in this smoking cessation trial among Chinese smokers. We conducted a double-blind, placebo-controlled, 8-week trial of SNT with a follow-up at week 12 among 250 Chinese smokers. Efficacy and safety were evaluated at day 4 and weeks 2, 4, 6, 8, and 12. Abstinence was biochemically verified by exhaled carbon monoxide (CO) and urine cotinine. The COMT Val108Met genotype was determined as a restriction fragment length polymorphism. Our results showed that the success rates for complete abstinence were greater for active versus placebo treatments at 8 weeks (48 vs. 17 %) and 12 weeks (52 vs. 19 %) (both p < 0.0001). Craving was significantly reduced from week 2 on active treatment compared to placebo. Adverse events were mild and tolerable. We found a genotype by treatment interaction at 12 weeks with greater abstinence rates in the COMT Val/Val (50 vs. 15 %) than the Met/Val + Met/Met genotypes (46 vs. 25 %). We found that SNT significantly increased smoking abstinence, reduced craving and was well tolerated, and the COMT Val/Val genotype was associated with a greater improvement in smoking cessation.
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Ravenstijn PG, Drenth HJ, O'Neill MJ, Danhof M, de Lange EC. Evaluation of blood-brain barrier transport and CNS drug metabolism in diseased and control brain after intravenous L-DOPA in a unilateral rat model of Parkinson's disease. Fluids Barriers CNS 2012; 9:4. [PMID: 22316420 PMCID: PMC3298802 DOI: 10.1186/2045-8118-9-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2011] [Accepted: 02/08/2012] [Indexed: 11/16/2022] Open
Abstract
Background Changes in blood-brain barrier (BBB) functionality have been implicated in Parkinson's disease. This study aimed to investigate BBB transport of L-DOPA transport in conjunction with its intra-brain conversion, in both control and diseased cerebral hemispheres in the unilateral rat rotenone model of Parkinson's disease. Methods In Lewis rats, at 14 days after unilateral infusion of rotenone into the medial forebrain bundle, L-DOPA was administered intravenously (10, 25 or 50 mg/kg). Serial blood samples and brain striatal microdialysates were analysed for L-DOPA, and the dopamine metabolites DOPAC and HVA. Ex-vivo brain tissue was analyzed for changes in tyrosine hydroxylase staining as a biomarker for Parkinson's disease severity. Data were analysed by population pharmacokinetic analysis (NONMEM) to compare BBB transport of L-DOPA in conjunction with the conversion of L-DOPA into DOPAC and HVA, in control and diseased cerebral hemisphere. Results Plasma pharmacokinetics of L-DOPA could be described by a 3-compartmental model. In rotenone responders (71%), no difference in L-DOPA BBB transport was found between diseased and control cerebral hemisphere. However, in the diseased compared with the control side, basal microdialysate levels of DOPAC and HVA were substantially lower, whereas following L-DOPA administration their elimination rates were higher. Conclusions Parkinson's disease-like pathology, indicated by a huge reduction of tyrosine hydroxylase as well as by substantially reduced levels and higher elimination rates of DOPAC and HVA, does not result in changes in BBB transport of L-DOPA. Taking the results of this study and that of previous ones, it can be concluded that changes in BBB functionality are not a specific characteristic of Parkinson's disease, and cannot account for the decreased benefit of L-DOPA at later stages of Parkinson's disease.
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Chowdhury NI, Remington G, Kennedy JL. Genetics of antipsychotic-induced side effects and agranulocytosis. Curr Psychiatry Rep 2011; 13:156-65. [PMID: 21336863 DOI: 10.1007/s11920-011-0185-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Antipsychotic medication has been enormously helpful in the treatment of psychotic symptoms during the past several decades. Unfortunately, several important side effects that can cause significant morbidity and mortality. The two most common are abnormal involuntary movements (tardive dyskinesia) and weight gain progressing through diabetes to metabolic syndrome. A more rare and life-threatening adverse effect is clozapine-induced agranulocytosis (CIA), which has been linked to clozapine use. Clozapine itself has a unique position among antipsychotic medications, representing the treatment of choice in refractory schizophrenia. Unfortunately, the potential risk of agranulocytosis, albeit small, prevents the widespread use of clozapine. Very few genetic determinants have been clearly associated with CIA due to small sample sizes and lack of replication in subsequent studies. The HLA system has been the main hypothesized region of interest in the study of CIA, and several gene variants in this region have been implicated, particularly variants of the HLA-DQB1 locus. A preliminary genome-wide association study has been conducted on a small sample for CIA, and a signal from the HLA region was noted. However, efforts to identify key gene mechanisms that will be useful in predicting antipsychotic side effects in the clinical setting have not been fully successful, and further studies with larger sample sizes are required.
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Affiliation(s)
- Nabilah I Chowdhury
- Neurogenetics Section, Neuroscience Department, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario M5T1R8, Canada
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17
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Abstract
Cigarette smoking is the main preventable cause of death in developed countries, and the development of more effective treatments is necessary. Cumulating evidence suggests that cognitive enhancement may contribute to the addictive actions of nicotine. Several studies have demonstrated that nicotine enhances cognitive performance in both smokers and non-smokers. Genetic studies support the role of both dopamine (DA) and nicotinic acetylcholine receptors (nAChRs) associated with nicotine-induced cognitive enhancement. Based on knockout mice studies, beta2 nAChRs are thought to be essential in mediating the cognitive effects of nicotine. alpha7nAChRs are associated with attentional and sensory filtering response, especially in schizophrenic individuals. Genetic variation in D2 type DA receptors and the catechol-O-methyltransferase enzyme appears to moderate cognitive deficits induced by smoking abstinence. Serotonin transporter (5-HTT) gene variation also moderates nicotine-induced improvement in spatial working memory. Less is known about the contribution of genetic variation in DA transporter and D4 type DA receptor genetic variation on the cognitive effects of nicotine. Future research will provide a clearer understanding of the mechanism underlying the cognitive-enhancing actions of nicotine.
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Affiliation(s)
- Aryeh I Herman
- Department of Psychiatry and VA Connecticut Healthcare System, School of Medicine, Yale University, West Haven, CT 06516, USA
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Käenmäki M, Tammimäki A, Garcia-Horsman JA, Myöhänen T, Schendzielorz N, Karayiorgou M, Gogos JA, Männistö PT. Importance of membrane-bound catechol-O-methyltransferase in L-DOPA metabolism: a pharmacokinetic study in two types of Comt gene modified mice. Br J Pharmacol 2010; 158:1884-94. [PMID: 19930170 DOI: 10.1111/j.1476-5381.2009.00494.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND AND PURPOSE Catechol-O-methyltransferase (COMT) metabolizes compounds containing catechol structures and has two forms: soluble (S-COMT) and membrane-bound (MB-COMT). Here we report the generation of a mouse line that expresses MB-COMT but not S-COMT. We compared the effects of deleting S-COMT only or both COMT forms on the pharmacokinetics of oral L-DOPA. EXPERIMENTAL APPROACH L-DOPA (10 mg kg(-1)) and carbidopa (30 mg kg(-1)) were given to mice by gastric tube, and samples were taken at various times. HPLC was used to measure L-DOPA in plasma and tissue samples, and dopamine and its metabolites in brain. Immunohistochemistry and Western blotting were used to characterize the distribution of COMT protein isoforms. KEY RESULTS Lack of S-COMT did not affect the levels of L-DOPA in plasma or peripheral tissues, whereas in the full COMT-knock-out mice, these levels were increased. The levels of 3-O-methyldopa were significantly decreased in the S-COMT-deficient mice. In the brain, L-DOPA levels were not significantly increased, and dopamine was increased only in females. The total COMT activity in the S-COMT-deficient mice was 22-47% of that in the wild-type mice. In peripheral tissues, female mice had lower COMT activity than the males. CONCLUSIONS AND IMPLICATIONS In S-COMT-deficient mice, MB-COMT in the liver and the duodenum is able to O-methylate about one-half of exogenous L-DOPA. Sexual dimorphism and activity of the two COMT isoforms seems to be tissue specific and more prominent in peripheral tissues than in the brain.
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Affiliation(s)
- M Käenmäki
- Division of Pharmacology and Toxicology, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
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Abstract
Currently available antipsychotic drugs (APDs) carry significant, though highly variable, liability to neurologic and metabolic side effects. Pharmacogenetics approaches offer the possibility of identifying patient-specific biomarkers for predicting risk of these side effects. To date, a few single nucleotide polymorphisms (SNPs) in a handful of genes have received convergent support across multiple studies. The primary focus has been on SNPs in dopamine and serotonin receptor genes: persuasive meta-analytic evidence exists for an effect of the dopamine D2 and D3 receptor genes (DRD2 and DRD3) in risk for tardr inesia (TD) and for an effect of variation at the receptor gene (HTR2C) for liability to APD-inducec gain. However, effect sizes appear to be modest, and pharmacoeconomic considerations have not been sufficiently studied, thereby limiting clinical applicability at this time. Effects of these genes and others on risk for TD, extrapyramidal side effects, hyperprolactinemia, and weight gain are revieved in this article.
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Affiliation(s)
- Todd Lencz
- Center for Translational Psychiatry, Feinstein Institute for Medical Research, North Shore-Long Island Jewish Health System, Glen Oaks, NY, USA
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20
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Guillot TS, Miller GW. Protective actions of the vesicular monoamine transporter 2 (VMAT2) in monoaminergic neurons. Mol Neurobiol 2009; 39:149-70. [PMID: 19259829 DOI: 10.1007/s12035-009-8059-y] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Accepted: 02/18/2009] [Indexed: 12/13/2022]
Abstract
Vesicular monoamine transporters (VMATs) are responsible for the packaging of neurotransmitters such as dopamine, serotonin, norepinephrine, and epinephrine into synaptic vesicles. These proteins evolved from precursors in the major facilitator superfamily of transporters and are among the members of the toxin extruding antiporter family. While the primary function of VMATs is to sequester neurotransmitters within vesicles, they can also translocate toxicants away from cytosolic sites of action. In the case of dopamine, this dual role of VMAT2 is combined-dopamine is more readily oxidized in the cytosol where it can cause oxidative stress so packaging into vesicles serves two purposes: neurotransmission and neuroprotection. Furthermore, the deleterious effects of exogenous toxicants on dopamine neurons, such as MPTP, can be attenuated by VMAT2 activity. The active metabolite of MPTP can be kept within vesicles and prevented from disrupting mitochondrial function thereby sparing the dopamine neuron. The highly addictive drug methamphetamine is also neurotoxic to dopamine neurons by using dopamine itself to destroy the axon terminals. Methamphetamine interferes with vesicular sequestration and increases the production of dopamine, escalating the amount in the cytosol and leading to oxidative damage of terminal components. Vesicular transport seems to resist this process by sequestering much of the excess dopamine, which is illustrated by the enhanced methamphetamine neurotoxicity in VMAT2-deficient mice. It is increasingly evident that VMAT2 provides neuroprotection from both endogenous and exogenous toxicants and that while VMAT2 has been adapted by eukaryotes for synaptic transmission, it is derived from phylogenetically ancient proteins that originally evolved for the purpose of cellular protection.
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Affiliation(s)
- Thomas S Guillot
- Center for Neurodegenerative Disease, Emory University, Atlanta, GA, USA
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21
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Yavich L, Forsberg MM, Karayiorgou M, Gogos JA, Männistö PT. Site-specific role of catechol-O-methyltransferase in dopamine overflow within prefrontal cortex and dorsal striatum. J Neurosci 2007; 27:10196-209. [PMID: 17881525 PMCID: PMC6672678 DOI: 10.1523/jneurosci.0665-07.2007] [Citation(s) in RCA: 201] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Accumulating evidence from clinical and preclinical studies shows that catechol-O-methyltransferase (COMT) plays a significant role in dopamine metabolism in the prefrontal cortex, but not in the striatum. However, to what extent dopamine overflow in the prefrontal cortex and striatum is controlled by enzymatic degradation versus reuptake is unknown. We used COMT deficient mice to investigate the role of COMT in these two brain regions with in vivo voltammetry. A real-time analysis of evoked dopamine overflow showed that removal of dopamine was twofold slower in the prefrontal cortex of mice lacking COMT than in wild-type mice, indicating that half of the dopamine decline in this brain region results from COMT-mediated enzymatic degradation. Lack of COMT did not influence dopamine overflow/decline in the dorsal striatum. COMT-deficient mice demonstrated a small (20-25%) but consistent increase in evoked dopamine release in the prefrontal cortex, but not in the dorsal striatum. Cocaine affected equally dopaminergic neurotransmission in the prefrontal cortex in both genotypes by prolonging 3-4 times dopamine elimination from extracellular space. Paradoxically, this happened without increase of the peak levels of evoked dopamine release. The present findings represent the first demonstration of the significant contribution of COMT in modulating the dynamics of dopamine overflow in the prefrontal cortex and underscore the therapeutic potential of manipulating COMT activity to alter dopaminergic neurotransmission in the prefrontal cortex.
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Affiliation(s)
- Leonid Yavich
- In Vivo Voltammetry Contract Research Laboratory and Department of Pharmacology and Toxicology, University of Kuopio, FIN-70211 Kuopio, Finland.
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Bonifácio MJ, Palma PN, Almeida L, Soares‐da‐Silva P. Catechol-O-methyltransferase and its inhibitors in Parkinson's disease. CNS DRUG REVIEWS 2007; 13:352-79. [PMID: 17894650 PMCID: PMC6494163 DOI: 10.1111/j.1527-3458.2007.00020.x] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Parkinson's disease (PD) is a neurological disorder characterized by the degeneration of dopaminergic neurons, with consequent reduction in striatal dopamine levels leading to characteristic motor symptoms. The most effective treatment for this disease continues to be the dopamine replacement therapy with levodopa together with an inhibitor of aromatic amino acid decarboxylase (AADC). The efficacy of this therapy, however, decreases with time and most patients develop fluctuating responses and dyskinesias. The last decade showed that the use of catechol-O-methyltransferase inhibitors as adjuvants to the levodopa/AADC inhibitor therapy, significantly improves the clinical benefits of this therapy. The purpose of this article is to review the current knowledge on the enzyme catechol-O-methyltransferase (COMT) and the role of COMT inhibitors in PD as a new therapeutic approach to PD involving conversion of levodopa to dopamine at the target region in the brain and facilitation of the continuous action of this amine at the receptor sites. A historical overview of the discovery and development of COMT inhibitors is presented with a special emphasis on nebicapone, presently under clinical development, as well as entacapone and tolcapone, which are already approved as adjuncts in the therapy of PD. This article reviews human pharmacokinetic and pharmacodynamic properties of these drugs as well as their clinical efficacy and safety.
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Affiliation(s)
- Maria João Bonifácio
- Department of Research and Development, BIAL (Portela & Co S.A.), S Mamede do Coronado, Portugal
| | - P. Nuno Palma
- Department of Research and Development, BIAL (Portela & Co S.A.), S Mamede do Coronado, Portugal
| | - Luís Almeida
- Department of Research and Development, BIAL (Portela & Co S.A.), S Mamede do Coronado, Portugal
- Institute of Pharmacology and Therapeutics, Faculty of Medicine, Porto, Portugal
| | - Patrício Soares‐da‐Silva
- Department of Research and Development, BIAL (Portela & Co S.A.), S Mamede do Coronado, Portugal
- Institute of Pharmacology and Therapeutics, Faculty of Medicine, Porto, Portugal
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Mohamed GG, Zayed MA, El-Dien FAN, El-Nahas RG. IR, UV-Vis, magnetic and thermal characterization of chelates of some catecholamines and 4-aminoantipyrine with Fe(III) and Cu(II). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2004; 60:1775-1781. [PMID: 15248950 DOI: 10.1016/j.saa.2003.08.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2003] [Accepted: 08/01/2003] [Indexed: 05/24/2023]
Abstract
The dopamine derivatives participate in the regulation of wide variety of physiological functions in the human body and in medication life. Increase and/or decrease in the concentration of dopamine in human body reflect an indication for diseases such as Schizophrenia and/or Parkinson diseases. Alpha-methyldopa (alpha-MD) in tablets is used in medication of hypertension. The Fe(III) and Cu(II) chelates with coupled products of adrenaline hydrogen tartarate (AHT), levodopa (LD), alpha-MD and carbidopa (CD) with 4-aminoantipyrine (4-AAP) are prepared and characterized. Different physico-chemical methods like IR, magnetic and UV-Vis spectra are used to investigate the structure of these chelates. Fe(III) form 1:2 (M:catecholamines) chelates while Cu(II) form 1:1 chelates. Catecholamines behave as a bidentate mono- or dibasic ligands in binding to the metal ions. IR spectra show that the catecholamines are coordinated to the metal ions in a bidentate manner with O,O donor sites of the phenolic -OH. Magnetic moment measurements reveal the presence of Fe(III) chelates in octahedral geometry while the Cu(II) chelates are square planar. The thermal decomposition of Fe(III) and Cu(II) complexes is studied using thermogravimetric (TGA) and differential thermal analysis (DTA) techniques. The water molecules are removed in the first step followed immediately by decomposition of the ligand molecules. The activation thermodynamic parameters, such as, energy of activation, enthalpy, entropy and free energy change of the complexes are evaluated and the relative thermal stability of the complexes are discussed.
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Affiliation(s)
- Gehad G Mohamed
- Chemistry Department, Faculty of Science, Cairo University, Giza, Egypt.
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24
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Taskinen J, Ethell BT, Pihlavisto P, Hood AM, Burchell B, Coughtrie MWH. Conjugation of catechols by recombinant human sulfotransferases, UDP-glucuronosyltransferases, and soluble catechol O-methyltransferase: structure-conjugation relationships and predictive models. Drug Metab Dispos 2003; 31:1187-97. [PMID: 12920175 DOI: 10.1124/dmd.31.9.1187] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Conjugation of a structurally diverse set of 53 catechol compounds was studied in vitro using six recombinant human sulfotransferases (SULTs), five UDP-glucuronosyltransferases (UGT) and the soluble form of catechol O-methyltransferase (S-COMT) as catalyst. The catechol set comprised endogenous compounds, such as catecholamines and catecholestrogens, drugs, natural plant constituents, and other catechols with diverse substituent properties and substitution patterns. Most of the catechols studied were substrates of S-COMT and four SULT isoforms (1A1, 1A2, 1A3, and 1B1), but the rates of conjugation varied considerably, depending on the substrate structure and the enzyme form. SULT1E1 sulfated fewer catechols. Only low activities were observed for SULT1C2. UGT1A9 glucuronidated catechols representing various structural classes, and almost half of the studied compounds were glucuronidated at a high rate. The other UGT enzymes (1A1, 1A6, 2B7, and 2B15) showed narrower substrate specificity for catechols, but each glucuronidated some catechols at a high rate. Dependence of specificity and rate of conjugation on the molecular structure of the substrate was characterized by structure-activity relationship analysis and quantitative structure-activity relationship modeling. Twelve structural descriptors were used to characterize lipophilicity/polar interaction properties, steric properties, and electronic effects of the substituents modifying the catechol structure. PLS models explaining more than 80% and predicting more than 70% of the variance in conjugation activity were derived for the representative enzyme forms SULT1A3, UGT1A9, and S-COMT. Several structural factors governing the conjugation of catechol hormones, metabolites, and drugs were identified. The results have significant implications for predicting the metabolic fate of catechols.
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Affiliation(s)
- Jyrki Taskinen
- Department of Pharmacy, University of Helsinki, Helsinki, Finland.
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25
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Lautala P, Ulmanen I, Taskinen J. Molecular mechanisms controlling the rate and specificity of catechol O-methylation by human soluble catechol O-methyltransferase. Mol Pharmacol 2001; 59:393-402. [PMID: 11160877 DOI: 10.1124/mol.59.2.393] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Molecular mechanisms determining the turn-over rate and specificity of catechol O-methylation were studied by combining enzyme kinetic measurements, computational modeling of substrate properties and fitting ligands in a 3D model of the active site of the enzyme. Enzyme kinetic measurements were carried out for 46 compounds, including most clinically used catechol drugs, by using recombinant human soluble catechol O-methyltransferase (COMT). The most important mechanism decreasing the turnover rate and increasing affinity was the electron withdrawing effect of substituents. Several other mechanisms by which substituents affected reactivity and affinity were identified. Highest turnover rates were determined for unsubstituted catechol and pyrogallol. Pyrogallol derivatives generally seemed to be more specific substrates than catechols. Catecholestrogens were the most specific endogenous substrates, whereas catecholamines were rather poor substrates. Among the catechol drugs used in the L-DOPA treatment of Parkinson's disease, the COMT inhibitors entacapone and tolcapone were not methylated, whereas the DOPA decarboxylase inhibitor benserazide was 15 times more specific substrate than L-DOPA, the target of COMT inhibition. The structure-activity relationships found allow the prediction of reactivity, affinity, and specificity with useful accuracy for catechols with a wide range of structures and properties. The knowledge can be used in the evaluation of metabolic interactions of endogenous catechols, drugs and dietary catechols, and in the designing of drugs with the catechol pharmacophore.
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Affiliation(s)
- P Lautala
- Department of Pharmacy, Viikki Drug Discovery Technology Center, University of Helsinki, Finland
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Gerlach M, Xiao AY, Kuhn W, Lehnfeld R, Waldmeier P, Sontag KH, Riederer P. The central catechol-O-methyltransferase inhibitor tolcapone increases striatal hydroxyl radical production in L-DOPA/carbidopa treated rats. J Neural Transm (Vienna) 2001; 108:189-204. [PMID: 11314772 DOI: 10.1007/s007020170087] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Inhibition of catechol catechol-O-methyltransferase (COMT) in the brains of subjects treated with L-DOPA (L-3,4-dihydroxylphenylalanine) and an aromatic amino acid decarboxylase (AADC) inhibitor is suggested to cause an increase of L-DOPA, which might lead to oxidative damage through enhanced formation of free radicals. To investigate this hypothesis, the acute effects of two doses of the systemically administered COMT inhibitors entacapone (peripheral) and tolcapone (peripheral and central) on the extracellular formation of hydroxyl radicals in vivo following treatment with L-DOPA and the AADC inhibitor carbidopa were examined. The formation of extracellular hydroxyl radicals were determined by the measurement of 2,3-dihydroxybenzoic acid (2,3-DHBA), a reaction product of hydroxyl radicals with sodium salicylate, using microdialysis in the striatum of anesthetised rats. The COMT inhibitors were administered together with 50 mg/kg i.p. carbidopa as 5% gum arabic suspensions intraperitoneally (i.p.) at doses of 0, 1.0, and 10 mg/kg body weight to a total of 36 male HAN-Wistars rats. L-DOPA was injected i.p. 40 min after drugs of interest. Microdialysis samples were collected every 20 min for 400 min at a perfusion rate of 1 microl/min. Systemically administered 10 mg/kg tolcapone, but not entacapone, induced an increase in hydroxyl radical formation in the striatum of anesthetised rats following treatment with L-DOPA/carbidopa. The increase in hydroxyl radical formation was reflected by higher extracellular concentrations of the hydroxylate product of salicylate, 2,3-DHBA, peaking at 192% of baseline at the end of the observation period. Similar results were also found using the AUC (area under the curve) value estimated for the observation period. We conclude that the increase in hydroxyl radical formation is likely to result from an increased rate of monoamine oxidase-mediated and non-enzymatic (autoxidation) dopamine metabolism following increased central availability caused by reduction in COMT-mediated metabolism. We cannot, however, exclude the possibility that hydroxyl radicals are produced by tolcapone as a result of uncoupling mitochondrial oxidative phosphorylation.
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Affiliation(s)
- M Gerlach
- Department of Psychiatry and Psychotherapy, University of Würzburg, Federal Republic of Germany.
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Abstract
The kidney regulates sodium metabolism with extraordinary precision and sensitivity. This is accomplished by an intricate interaction between signals from extrarenal and intrarenal sources and between anti-natriuretic and natriuretic factors. Dopamine, produced in renal proximal tubule cells, plays a central role in this interactive network. Natriuretic hormones that are released from extrarenal sources, such as atrial natriuretic peptide, mediate some of their effects via renal dopamine receptors. On the level of the tubules, dopamine acts by opposing the effects of anti-natriuretic factors, such as angiotensin II and alpha-adrenergic receptors. Sodium retention leads to an increase in renal dopamine tonus, and the natriuretic effects of dopamine are more prominent under this condition. Inhibition or down-regulation of dopamine receptors significantly attenuates the natriuretic response to salt loading. Renal dopamine is modulated by the supply of filtered L-DOPA and the metabolism of dopamine via catechol-O-methyldopamine. The importance of dopamine as a natriuretic hormone is reflected by its capacity to inhibit the majority of renal tubule sodium transporters. Notably, the activity of Na+, K+ ATPase is inhibited in most tubule segments by dopamine. Recent studies have elucidated many of the signaling pathways for renal dopamine receptors. Novel principles for homologous and heterologous sensitization of dopamine receptors have been detected that may explain some of the interaction between dopamine and other first messengers that modulate renal tubule sodium transport. A broad understanding of the renal dopamine system has become increasingly important, since there is now strong evidence from both clinical and experimental studies that dysregulation of the renal dopamine system plays a role in many forms of multigenetic hypertension.
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Affiliation(s)
- A C Aperia
- Karolinska Institutet, Department of Woman and Child Health, Stockholm, Sweden
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Ovaska M, Yliniemelä A. A semiempirical study on inhibition of catechol O-methyltransferase by substituted catechols. J Comput Aided Mol Des 1998; 12:301-7. [PMID: 9749372 DOI: 10.1023/a:1007965026738] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Catechol and endogenous catechol derivatives are readily methylated by catechol O-methyltransferase (COMT). In contrast, many catechol derivatives possessing electronegative substituents are potent COMT inhibitors. The X-ray structure of the active site of COMT suggests that the methylation involves a lysine as a general base. The lysine can activate one of the catecholic hydroxyl groups for a nucleophilic attack on the active methyl group of the coenzyme S-adenosyl-L-methionine (AdoMet). We studied the effect of dinitrosubstitution of the catecholic ring at the semiempirical PM3 level on the methylation reaction catalysed by COMT. The electronegative nitro groups make the ionized catechol hydroxyls less nucleophilic than the corresponding hydroxyl groups of the non-substituted catechol. As a consequence, dinitrocatechol is not methylated but is instead a potent COMT inhibitor. The implications of this mechanism to the design of COMT inhibitors are discussed.
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Affiliation(s)
- M Ovaska
- Orion Pharma, Orion Corporation, Espoo, Finland
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Baas H, Beiske AG, Ghika J, Jackson M, Oertel WH, Poewe W, Ransmayr G. Catechol-O-methyltransferase inhibition with tolcapone reduces the "wearing off" phenomenon and levodopa requirements in fluctuating parkinsonian patients. J Neurol Neurosurg Psychiatry 1997; 63:421-8. [PMID: 9343116 PMCID: PMC2169755 DOI: 10.1136/jnnp.63.4.421] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND More than 50% of patients with Parkinson's disease develop motor response fluctuations (the "wearing off" phenomenon) after more than five years of levodopa therapy. Inhibition of catechol-O-methyltransferase by tolcapone has been shown to increase levodopa bioavailability and plasma elimination half life, thereby prolonging the efficacy of levodopa. OBJECTIVES The primary objective was to evaluate the efficacy of tolcapone in reducing "wearing off" in levodopa treated, fluctuating parkinsonian patients. Secondary objectives included assessment of reduction in levodopa requirements, improvement in patients' clinical status, duration of improvements, and tolerability of tolcapone. METHODS In this multicentre, randomised, double blind, placebo controlled trial, 58 patients received placebo, 60 received 100 mg tolcapone three times daily (tid), and 59 received 200 mg tolcapone tid, in addition to levodopa/benserazide. RESULTS After three months with 200 mg tolcapone tid, "off" time decreased by 26.2% of the baseline value, "on" time increased by 20.6% (P<O.01 v placebo), and the mean total daily levodopa dose decreased by 122 mg from the baseline dose of 676 mg (P<0.01). These responses were maintained up to nine months. With 100 mg tolcapone tid, "off" time decreased by 31.5% (P<0.05), "on" time increased by 21.3% (P<0.01), and the mean total daily levodopa dose decreased by 109 mg from the baseline dose of 668 mg (P<0.05). With 200 mg tolcapone tid, unified Parkinson's disease rating scale motor and total scores were significantly reduced, and quality of life (sickness impact profile) scores were significantly improved. Both dosages were well tolerated. Dyskinesia was the most often reported levodopa induced adverse event. Diarrhea was the most often reported non-dopaminergic adverse event and the most frequent reason for withdrawal from the study: four patients in the 100 mg tolcapone tid group and six in the 200 mg tid group withdrew because of diarrhea. CONCLUSION Tolcapone prolongs "on" time in fluctuating parkinsonian patients while allowing a reduction in daily levodopa dosage, thereby improving the efficacy of long term levodopa therapy.
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Affiliation(s)
- H Baas
- Klinik für Neurologie, Klinikum der Johann-Wolfgang-Goethe-Universitaet, Frankfurt, Germany
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Khromova I, Voronina T, Kraineva VA, Zolotov N, Männistö PT. Effects of selective catechol-O-methyltransferase inhibitors on single-trial passive avoidance retention in male rats. Behav Brain Res 1997; 86:49-57. [PMID: 9105581 DOI: 10.1016/s0166-4328(96)02242-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effects of new selective catechol-O-methyltransferase (COMT) inhibitors entacapone (mainly peripheral effect) and tolcapone (acting also in the brain) on normal and impaired cognitive functions were studied in aversively motivated inhibitory avoidance using a single-trial passive avoidance paradigm in young adult rats. Passive avoidance retention latency was shortened by either scopolamine (1.0 mg/kg) or bilateral lesions to nucleus basalis magnocellularis (NBM) caused by infusions of ethylcholine aziridinium (AF64A). Entacapone (30 mg/kg) administered once before training or before the retention test, 24 h after training, prevented the effect of scopolamine but did not alter extinction in these rats. However, entacapone (30 mg/kg) prolonged lag time when given during the extinction process to intact rats after training. Tolcapone administered once before training (10 mg/kg) counteracted the effect of scopolamine. It prolonged retention latency of the intact rats when given after training (10 mg/kg). Tolcapone (3 mg/kg) also prolonged lag time when given during extinction to rats bearing NBM lesions. The effect of scopolamine on extinction and retrieval was not prevented by tolcapone. Only entacapone improved memory storage. Collectively, the present results indicate that COMT inhibitors prolong retention latencies in a single-trial passive avoidance test assessed at several memory phases.
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Affiliation(s)
- I Khromova
- Russian Academy of Medical Sciences, Institute of Pharmacology, Moscow, Russia
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Merello M, Lees AJ, Webster R, Bovingdon M, Gordin A. Effect of entacapone, a peripherally acting catechol-O-methyltransferase inhibitor, on the motor response to acute treatment with levodopa in patients with Parkinson's disease. J Neurol Neurosurg Psychiatry 1994; 57:186-9. [PMID: 8126502 PMCID: PMC1072447 DOI: 10.1136/jnnp.57.2.186] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Catechol-O-methyltransferase (COMT) inhibitors may be useful in the treatment of Parkinson's disease by improving the bioavailability of levodopa and by prolonging its effects. Entacapone (OR-611), a novel COMT inhibitor, which does not cross the blood brain barrier, was assessed in 12 patients with Parkinson's disease and motor fluctuations in a randomised, double-blind, cross-over, single dose study. The magnitude and duration of the therapeutic response to a single dose of 200 mg levodopa/50 mg carbidopa was evaluated after concomitant placebo, or 200 or 800 mg entacapone. A significant increase in the duration of the motor response to levodopa was seen when 200 mg entacapone was given with levodopa/carbidopa. Plasma levodopa concentrations were increased with both doses of the COMT inhibitor. The latency to onset of motor response did not differ significantly between active drug and placebo. Entacapone may prove useful in prolonging the duration of the benefit obtained from individual doses of levodopa.
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Affiliation(s)
- M Merello
- Department of Neurology, University College and Middlesex Hospitals School of Medicine, London, UK
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Wikberg T, Ottoila P, Taskinen J. Identification of major urinary metabolites of the catechol-O-methyltransferase inhibitor entacapone in the dog. Eur J Drug Metab Pharmacokinet 1993; 18:359-67. [PMID: 8020535 DOI: 10.1007/bf03190186] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Metabolites of entacapone, (E)-2-cyano-N,N-diethyl-3-(3,4-dihydroxy-5-nitrophenyl) propenamide, a potent inhibitor of catechol-O-methyltransferase, were isolated from dog urine. After hydrolysis of glucuronides and sulfates, 5 metabolites were identified in addition to unchanged entacapone by HPLC with diode-array UV detection, electron ionization mass spectrometry and IR spectroscopy. The (Z)-isomer of entacapone was the most abundant phase I metabolite while less abundant metabolites were formed through cleavage or reduction of the side chain carbon-carbon double bond, hydrolysis of the amide bond or through hydration of the nitrile group. The most abundant urinary metabolites were glucuronides. The glucuronidation site of these ortho-nitrocatechols was shown to be the hydroxyl meta to the nitro group.
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Affiliation(s)
- T Wikberg
- Orion-Farmos Pharmaceuticals, Orion Research Center, Espoo, Finland
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Müller T, Kuhn W, Przuntek H. Therapy with central active catechol-O-methyltransferase (COMT)-inhibitors: is addition of monoamine oxidase (MAO)-inhibitors necessary to slow progress of neurodegenerative disorders? J Neural Transm (Vienna) 1993; 92:187-95. [PMID: 8369108 DOI: 10.1007/bf01244877] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Neurotrophic factors, like e.g. nerve growth factor (NGF), neurotrophin 3 (NT-3) or brain-derived neurotrophic factor (BDNF) promote the survival and function of neurones in the peripheral and central nervous system. Dopamine or other biogenic amines induce the biosynthesis of neurotrophic factors in glial and neuronal cells. Therefore inhibition of enzymes, like the extraneuronal and neuronal located MAO or the predominantly glial situated COMT, which both metabolize catecholamines, may induce an increased biosynthesis of neurotrophic factors. Due to clinical studies especially MAO-B-inhibitors appear to slow the progression of neurological deficits in Parkinson's disease and the cognitive decline in Alzheimer's disease. On the one hand inhibition of COMT alone may also slow the metabolisation of biogenic amines in glial cells and may consequently induce synthesis of neurotrophic factors in glial cells. But on the other hand in vivo and in vitro studies show, that COMT-inhibitors may intensify the metabolisation of catecholamines in neurones by MAO, what may cause an enhanced generation of free radicals. This increase of free radicals may induce lipid peroxidation of membranes and therefore cause accelerated neuronal and glial cell death. For that reason we conclude, that centrally active COMT-inhibitors may only be used together with MAO-inhibitors in the neuroprotective treatment of neurodegenerative disorders. Medical treatment with both inhibitors will have to be performed very carefully due to cytotoxic effects of high catecholamine levels on neuronal and glial cells and due to possible prolongation or potentiation of the activity of several noradrenergic drugs in the periphery.
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Affiliation(s)
- T Müller
- Department of Neurology, St. Josef-Hospital, University of Bochum, Federal Republic of Germany
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