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Vaziri N, Marques D, Greenway SC, Bousman CA. The cellular mechanism of antipsychotic-induced myocarditis: A systematic review. Schizophr Res 2023; 261:206-215. [PMID: 37797362 DOI: 10.1016/j.schres.2023.09.039] [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: 01/22/2023] [Revised: 04/23/2023] [Accepted: 09/24/2023] [Indexed: 10/07/2023]
Abstract
Antipsychotic drug-induced myocarditis is a serious and potentially fatal adverse drug reaction characterized by inflammation of the heart muscle (myocardium) that typically develops within the first month after commencing an antipsychotic drug. Although the precise mechanism of this severe adverse drug reaction is unknown, multiple theories have been proposed with varying levels of support from cellular or animal studies. We conducted a systematic review, in accordance with PRISMA guidelines, of published preclinical and clinical studies investigating the cellular mechanism by which antipsychotic drugs induce myocarditis. A literature search including all studies available before December 10, 2022, yielded 15 studies that met our inclusion criteria. Antipsychotics examined in the included studies included clozapine (n = 13), ziprasidone (n = 1), amisulpride (n = 1), haloperidol (n = 1), levomepromazine (n = 1), olanzapine (n = 1), and sertindole (n = 1). The evidence suggests several overlapping mechanistic cascades involving: (1) increased levels of catecholamines, (2) increased proinflammatory cytokines, (3) increased reactive oxygen species (ROS), (4) reduced antioxidant levels and activity, and (5) mitochondrial damage. Notable limitations such as, a focus on clozapine, sample heterogeneity, and use of supratherapeutic doses will need to be addressed in future studies. Discovery of the mechanism by which antipsychotic drugs induce myocarditis will allow the development of clinically-useful biomarkers to identify those patients at increased risk prior to drug exposure. The development or repurposing of therapeutics to prevent or treat drug-induced myocarditis will also be possible and this will enable increased and safe use of antipsychotics for those patients in need.
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Affiliation(s)
- Nazanin Vaziri
- Department of Medical Genetics, University of Calgary, Calgary, AB, Canada
| | - Diogo Marques
- Department of Medical Genetics, University of Calgary, Calgary, AB, Canada
| | - Steven C Greenway
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Cardiac Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Chad A Bousman
- Department of Medical Genetics, University of Calgary, Calgary, AB, Canada; Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Psychiatry, University of Calgary, Calgary, AB, Canada; Department of Physiology & Pharmacology, University of Calgary, Calgary, AB, Canada; Department of Community Health Sciences, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
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2
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Hodgkin Lymphoma in Patients Receiving Clozapine Treatment: 2 Case Reports and Literature Review. J Clin Psychopharmacol 2023; 43:180-183. [PMID: 36735587 DOI: 10.1097/jcp.0000000000001651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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3
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Thomson P, Hammond S, Naisbitt DJ. Pathology of drug hypersensitivity reactions and mechanisms of immune tolerance. Clin Exp Allergy 2022; 52:1379-1390. [PMID: 36177544 DOI: 10.1111/cea.14235] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/08/2022] [Accepted: 09/25/2022] [Indexed: 01/26/2023]
Abstract
Immune-mediated type IV adverse drug reactions are idiosyncratic in nature, generally not related to the primary or secondary pharmacology of the drug. Due to their complex nature and rarity, these iatrogenic reactions are seldom predicted or encountered during preclinical/early clinical development stages, and often precipitate upon exposure to wider populations (i.e. phase III onwards). They confer a burden on the healthcare sector in both a clinical and financial sense presenting a severe impediment to the drug discovery and development process. Research over the past 50 years has improved our understanding of these reactions markedly as both in vitro and in vivo studies have placed the role of the immune system, in particular; drug-responsive T cells, firmly in the spotlight as the mediators of these reactions. Indeed, the role of different populations of T cells in adverse events and the interaction of drug molecules with HLA proteins expressed on the surface of antigen-presenting cells is of considerable interest. Herein, this review examines the pathways of immune-mediated adverse events including the various T cell subtypes implicated and the mechanisms of T cell activation. Additionally, we address the enigma of immunological tolerance and explore the role tolerance plays in determination of susceptibility to such adverse events even in individuals carrying immunogenic liabilities.
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Affiliation(s)
- Paul Thomson
- Department of Molecular and Clinical Pharmacology, MRC Centre for Drug Safety Science, University of Liverpool, Liverpool, UK
| | - Sean Hammond
- Department of Molecular and Clinical Pharmacology, MRC Centre for Drug Safety Science, University of Liverpool, Liverpool, UK.,ApconiX, Alderley Park, Alderley Edge, UK
| | - Dean J Naisbitt
- Department of Molecular and Clinical Pharmacology, MRC Centre for Drug Safety Science, University of Liverpool, Liverpool, UK
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4
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Torii-Goto A, Yoshimi A, Tashiro Y, Ukigai M, Matsumoto A, Ozaki N, Noda Y. A Reactive Metabolite of Clozapine Induces Hematopoietic Toxicity in HL-60 Cells Undergoing Granulocytic Differentiation through Its Effect on Glutathione Metabolism. Biol Pharm Bull 2022; 45:1232-1237. [DOI: 10.1248/bpb.b22-00045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Aya Torii-Goto
- Division of Clinical Sciences and Neuropsychopharmacology, Faculty and Graduate School of Pharmacy, Meijo University
| | - Akira Yoshimi
- Department of Psychiatry, Nagoya University Graduate School of Medicine
| | - Yuko Tashiro
- Division of Clinical Sciences and Neuropsychopharmacology, Faculty and Graduate School of Pharmacy, Meijo University
| | - Mako Ukigai
- Division of Clinical Sciences and Neuropsychopharmacology, Faculty and Graduate School of Pharmacy, Meijo University
| | - Aoi Matsumoto
- Division of Clinical Sciences and Neuropsychopharmacology, Faculty and Graduate School of Pharmacy, Meijo University
| | - Norio Ozaki
- Department of Psychiatry, Nagoya University Graduate School of Medicine
| | - Yukihiro Noda
- Division of Clinical Sciences and Neuropsychopharmacology, Faculty and Graduate School of Pharmacy, Meijo University
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5
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Saito T, Usui T, Inada H, Miyawaki I, Mizuno K, Ikeda M, Iwata N. Clozapine-specific proliferative response of peripheral blood-derived mononuclear cells in Japanese patients with clozapine-induced agranulocytosis. J Psychopharmacol 2022; 36:1087-1094. [PMID: 35861221 DOI: 10.1177/02698811221112937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Although clozapine-induced granulocytopenia (CIG) is less severe than clozapine-induced agranulocytosis (CIA), and some patients with CIG may not go on to develop serious complications, clozapine is discontinued in cases of both CIA and CIG. Understanding the pathogenic mechanisms of CIA/CIG could provide better management of clozapine therapy. Recently, as a mechanistic insight into adaptive immune systems, European groups reported clozapine-specific proliferative responses and clozapine-specific T cells using blood taken from patients with CIA and/or CIG. AIMS The aims of our study are to support this mechanistic evidence and to investigate the difference in the lymphocyte response to clozapine between patients with CIG and those with CIA. METHODS Lymphocyte stimulation tests (LSTs) were conducted using CD25-positive cell-depleted peripheral blood-derived mononuclear cells (PBMCs) isolated from blood of four Japanese patients with CIA, four patients with CIG, and nine clozapine-tolerant subjects. RESULTS Three of four patients with CIA and one of four patients with CIG showed proliferative responses to clozapine with a stimulation index of greater than 2. In contrast, none of the nine clozapine-tolerant subjects showed any response to clozapine. Olanzapine did not stimulate PBMCs of patients with CIA, patients with CIG, or clozapine-tolerant subjects. CONCLUSIONS Clozapine- and CIA-specific lymphocyte reactions in a Japanese population provided supportive evidence that the pathogenesis of CIA is based on adaptive immune reactions. In addition, patients with CIG who show a positive response to an LST may at the very least not be chosen for clozapine-rechallenge and further prospective studies are desirable to verify this hypothesis.
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Affiliation(s)
- Takeo Saito
- Department of Psychiatry, School of Medicine, Fujita Health University, Aichi, Japan
| | - Toru Usui
- Preclinical Research Unit, Sumitomo Pharma Co., Ltd., Osaka, Japan
| | - Hiroshi Inada
- Preclinical Research Unit, Sumitomo Pharma Co., Ltd., Osaka, Japan
| | - Izuru Miyawaki
- Preclinical Research Unit, Sumitomo Pharma Co., Ltd., Osaka, Japan
| | | | - Masashi Ikeda
- Department of Psychiatry, School of Medicine, Fujita Health University, Aichi, Japan
| | - Nakao Iwata
- Department of Psychiatry, School of Medicine, Fujita Health University, Aichi, Japan
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6
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Ramli FF, Ali A, Syed Hashim SA, Kamisah Y, Ibrahim N. Reduction in Absolute Neutrophil Counts in Patient on Clozapine Infected with COVID-19. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182111289. [PMID: 34769806 PMCID: PMC8582734 DOI: 10.3390/ijerph182111289] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/24/2021] [Accepted: 10/26/2021] [Indexed: 12/12/2022]
Abstract
Despite its severe adverse effects, such as agranulocytosis, clozapine is the primary treatment for treatment-resistant schizophrenia. The established clozapine monitoring system has contributed to reducing agranulocytosis incidence and mortality rates. However, the pandemic coronavirus disease 2019 (COVID-19) has caused changes in the monitoring system. This review aimed to assess the current evidence on the neutrophil changes in the patient on clozapine treatment and infected with COVID-19. Individual cases reported various absolute neutrophil count (ANC) levels, normal, reduced, or elevated. No agranulocytosis case was reported. One case had a borderline moderate-severe ANC level, but the patient was in the 18-week period of clozapine treatment. A cumulative analysis of case the series initially reported inconclusive results. However, a more recent study with a larger sample size reported a significant reduction in the ANC during COVID-19 infection. Nevertheless, this effect is transient as no significant difference was found between the baseline and the post-infection period in ANC levels. In conclusion, COVID-19 is associated with a temporary reduction in ANC levels. The results supported the recommendation to reduce the frequency of clozapine monitoring in the eligible candidates. However, more data are required to confirm the current findings given the limitations, including study design, sample size, and statistical analysis.
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Affiliation(s)
- Fitri Fareez Ramli
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia; (S.A.S.H.); (Y.K.)
- Department of Psychiatry, University of Oxford, Oxford OX3 7JX, UK
- Correspondence: ; Tel.: +60-3-9145-9545
| | - Adli Ali
- Department of Pediatrics, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia;
- Infection and Immunology Health and Advanced Medicine Cluster, Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia
| | - Syed Alhafiz Syed Hashim
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia; (S.A.S.H.); (Y.K.)
| | - Yusof Kamisah
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur 56000, Malaysia; (S.A.S.H.); (Y.K.)
| | - Normala Ibrahim
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang 43400, Malaysia;
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7
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Rattay B, Benndorf RA. Drug-Induced Idiosyncratic Agranulocytosis - Infrequent but Dangerous. Front Pharmacol 2021; 12:727717. [PMID: 34483939 PMCID: PMC8414253 DOI: 10.3389/fphar.2021.727717] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Accepted: 07/27/2021] [Indexed: 12/21/2022] Open
Abstract
Drug-induced agranulocytosis is a life-threatening side effect that usually manifests as a severe form of neutropenia associated with fever or signs of sepsis. It can occur as a problem in the context of therapy with a wide variety of drug classes. Numerous drugs are capable of triggering the rare idiosyncratic form of agranulocytosis, which, unlike agranulocytosis induced by cytotoxic drugs in cancer chemotherapy, is characterised by “bizzare” type B or hypersensitivity reactions, poor predictability and a mainly low incidence. The idiosyncratic reactions are thought to be initiated by chemically reactive drugs or reactive metabolites that react with proteins and may subsequently elicit an immune response, particularly directed against neutrophils and their precursors. Cells or organs that exhibit specific metabolic and biotransformation activity are therefore frequently affected. In this review, we provide an update on the understanding of drug-induced idiosyncratic agranulocytosis. Using important triggering drugs as examples, we will summarise and discuss the chemical, the biotransformation-related, the mechanistic and the therapeutic basis of this clinically relevant and undesirable side effect.
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Affiliation(s)
- Bernd Rattay
- Department of Clinical Pharmacy and Pharmacotherapy, Institute of Pharmacy, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Ralf A Benndorf
- Department of Clinical Pharmacy and Pharmacotherapy, Institute of Pharmacy, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
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Chrétien B, Lelong-Boulouard V, Chantepie S, Sassier M, Bertho M, Brazo P, Humbert X, Alexandre J, Fedrizzi S, Dolladille C. Haematologic malignancies associated with clozapine v. all other antipsychotic agents: a pharmacovigilance study in VigiBase ®. Psychol Med 2021; 51:1459-1466. [PMID: 32036793 DOI: 10.1017/s0033291720000161] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Clozapine is mainly used in patients with treatment-resistant schizophrenia and may lead to potentially severe haematologic adverse events, such as agranulocytosis. Whether clozapine might be associated with haematologic malignancies is unknown. We aimed to assess the association between haematologic malignancies and clozapine using Vigibase®, the WHO pharmacovigilance database. METHODS We performed a disproportionality analysis to compute reporting odds-ratio adjusted for age, sex and concurrent reporting of antineoplastic/immunomodulating agents (aROR) for clozapine and structurally related drugs (loxapine, olanzapine and quetiapine) compared with other antipsychotic drugs. Cases were malignant lymphoma and leukaemia reports. Non-cases were all other reports including at least one antipsychotic report. RESULTS Of the 140 226 clozapine-associated reports, 493 were malignant lymphoma cases, and 275 were leukaemia cases. Clozapine was significantly associated with malignant lymphoma (aROR 9.14, 95% CI 7.75-10.77) and leukaemia (aROR 3.54, 95% CI 2.97-4.22). Patients suffering from those haematologic malignancies were significantly younger in the clozapine treatment group than patients treated with other medicines (p < 0.001). The median time to onset (available for 212 cases) was 5.1 years (IQR 2.2-9.9) for malignant lymphoma and 2.5 years (IQR 0.6-7.4) for leukaemia. The aROR by quartile of dose of clozapine in patients with haematologic malignancies suggested a dose-dependent association. CONCLUSIONS Clozapine was significantly associated with a pharmacovigilance signal of haematologic malignancies. The risk-benefit balance of clozapine should be carefully assessed in patients with risk factors of haematologic malignancies. Clozapine should be used at the lowest effective posology.
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Affiliation(s)
- Basile Chrétien
- Department of Pharmacology, Caen University Hospital, Caen, F-14000, France
- Pharmacovigilance Regional Center, Caen University Hospital, Caen, F-14000, France
| | - Véronique Lelong-Boulouard
- Department of Pharmacology, Caen University Hospital, Caen, F-14000, France
- Normandie Univ, UNICAEN, UFR Santé, INSERM UMR 1075, COMETE-MOBILITES "Vieillissement, Pathologie, Santé", 14000Caen, France
| | - Sylvain Chantepie
- Department of Clinical Haematology, Caen University Hospital, Caen, F-14000, France
| | - Marion Sassier
- Department of Pharmacology, Caen University Hospital, Caen, F-14000, France
- Pharmacovigilance Regional Center, Caen University Hospital, Caen, F-14000, France
| | - Mickael Bertho
- Department of Pharmacology, Caen University Hospital, Caen, F-14000, France
- Pharmacovigilance Regional Center, Caen University Hospital, Caen, F-14000, France
| | - Perrine Brazo
- Department of Psychiatry, Esquirol Center, Caen University Hospital, Caen, F-14000, France
- Normandie Univ, UNICAEN, EA7466, Imagerie et Stratégies Thérapeutiques de la Schizophrénie (ISTS), 14000Caen, France
| | - Xavier Humbert
- Department of Pharmacology, Caen University Hospital, Caen, F-14000, France
- Pharmacovigilance Regional Center, Caen University Hospital, Caen, F-14000, France
- General Practice Department, Normandie Univ, UNICAEN, 14000Caen, France
- Normandie Univ, UNICAEN, EA4650, Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, 14000Caen, France
| | - Joachim Alexandre
- Department of Pharmacology, Caen University Hospital, Caen, F-14000, France
- Pharmacovigilance Regional Center, Caen University Hospital, Caen, F-14000, France
- Normandie Univ, UNICAEN, EA4650, Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, 14000Caen, France
| | - Sophie Fedrizzi
- Department of Pharmacology, Caen University Hospital, Caen, F-14000, France
- Pharmacovigilance Regional Center, Caen University Hospital, Caen, F-14000, France
- Normandie Univ, UNICAEN, EA4650, Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, 14000Caen, France
| | - Charles Dolladille
- Department of Pharmacology, Caen University Hospital, Caen, F-14000, France
- Normandie Univ, UNICAEN, EA4650, Signalisation, électrophysiologie et imagerie des lésions d'ischémie-reperfusion myocardique, 14000Caen, France
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de With SAJ, Man WH, Maas C, ten Berg M, Cahn W, Koekman AC, van Solinge WW, Tak T. Neutrophil fluorescence in clozapine users is attributable to a 14kDa secretable protein. Pharmacol Res Perspect 2020; 8:e00627. [PMID: 32812697 PMCID: PMC7437349 DOI: 10.1002/prp2.627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 02/28/2020] [Accepted: 03/04/2020] [Indexed: 11/06/2022] Open
Abstract
Clozapine is the only antipsychotic agent with demonstrated efficacy in refractory schizophrenia. However, use of clozapine is hampered by its adverse effects, including potentially fatal agranulocytosis. Recently, we showed an association between neutrophil autofluorescence and clozapine use. In this study, we evaluated the subcellular localization of clozapine-associated fluorescence and tried to elucidate its source. Neutrophils of clozapine users were analyzed with fluorescence microscopy to determine the emission spectrum and localization of the fluorescence signal. Next, these neutrophils were stimulated with different degranulation agents to determine the localization of fluorescence. Lastly, isolated neutrophil lysates of clozapine users were separated by SDS-PAGE and evaluated. Clozapine-associated fluorescence ranged from 420 nm to 720 nm, peaking at 500-550 nm. Fluorescence was localized in a large number of small loci, suggesting granular localization of the signal. Neutrophil degranulation induced by Cytochalasin B/fMLF reduced fluorescence, whereas platelet-activating factor (PAF)/fMLF induced degranulation did not, indicating that the fluorescence originates from a secretable substance in azurophilic granules. SDS-PAGE of isolated neutrophil lysates revealed a fluorescent 14kDa band, suggesting that neutrophil fluorescence is likely to be originated from a 14kDa protein/peptide fragment. We conclude that clozapine-associated fluorescence in neutrophils is originating from a 14kDa soluble protein (fragment) present in azurophilic granules of neutrophils. This protein could be an autofluorescent protein already present in the cell and upregulated by clozapine, or a protein altered by clozapine to express fluorescence. Future studies should further explore the identity of this protein and its potential role in the pathophysiology of clozapine-induced agranulocytosis.
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Affiliation(s)
- Sera A. J. de With
- Department of PsychiatryUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Wai H. Man
- Department of Clinical PharmacyUniversity Medical Center UtrechtUtrechtThe Netherlands
- Department of Clinical PharmacyMeander Medical CenterAmersfoortThe Netherlands
| | - Coen Maas
- Department of Clinical Chemistry and HaematologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Maarten ten Berg
- Department of Clinical Chemistry and HaematologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Wiepke Cahn
- Department of PsychiatryUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Arnold C. Koekman
- Department of Clinical Chemistry and HaematologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Wouter W. van Solinge
- Department of Clinical Chemistry and HaematologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Tamar Tak
- Department of Respiratory MedicineLaboratory of Translational ImmunologyUniversity Medical Center UtrechtUtrechtThe Netherlands
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10
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Ogese MO, Lister A, Jenkins RE, Meng X, Alfirevic A, Douglas L, Mcloughlin R, Silva E, Park BK, Pirmohamed M, Naisbitt DJ. Characterization of Clozapine-Responsive Human T Cells. THE JOURNAL OF IMMUNOLOGY 2020; 205:2375-2390. [PMID: 32989092 DOI: 10.4049/jimmunol.2000646] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 08/27/2020] [Indexed: 01/02/2023]
Abstract
Use of the atypical antipsychotic clozapine is associated with life-threatening agranulocytosis. The delayed onset and the association with HLA variants are characteristic of an immunological mechanism. The objective of this study was to generate clozapine-specific T cell clones (TCC) and characterize pathways of T cell activation and cross-reactivity with clozapine metabolites and olanzapine. TCC were established and characterized by culturing PBMCs from healthy donors and patients with a history of clozapine-induced agranulocytosis. Modeling was used to explore the drug-HLA binding interaction. Global TCC protein changes were profiled by mass spectrometry. Six well-growing clozapine-responsive CD4+ and CD8+ TCC were used for experiments; activation of TCC required APC, with clozapine interacting directly at therapeutic concentrations with several HLA-DR molecules. TCC were also activated with N-desmethylclozapine and olanzapine at supratherapeutic concentrations. Marked changes in TCC protein expression profiles were observed when clozapine treatment was compared with olanzapine and the medium control. Docking of the compounds into the HLA-DRB1*15:01 and HLA-DRB1*04:01 binding clefts revealed that clozapine and olanzapine bind in a similar conformation to the P4-P6 peptide binding pockets, whereas clozapine N-oxide, which did not activate the TCC, bound in a different conformation. TCC secreted Th1, Th2, and Th22 cytokines and effector molecules and expressed TCR Vβ 5.1, 16, 20, and 22 as well as chemokine receptors CXCR3, CCR6, CCR4, and CCR9. Collectively, these data show that clozapine interacts at therapeutic concentrations with HLA-DR molecules and activates human CD4+ T cells. Olanzapine only activates TCC at supratherapeutic concentrations.
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Affiliation(s)
- Monday O Ogese
- Medical Research Council Centre for Drug Safety Science, Department Molecular and Clinical Pharmacology, University of Liverpool, Liverpool L69 3GE, United Kingdom
| | - Adam Lister
- Medical Research Council Centre for Drug Safety Science, Department Molecular and Clinical Pharmacology, University of Liverpool, Liverpool L69 3GE, United Kingdom
| | - Rosalind E Jenkins
- Medical Research Council Centre for Drug Safety Science, Department Molecular and Clinical Pharmacology, University of Liverpool, Liverpool L69 3GE, United Kingdom
| | - Xiaoli Meng
- Medical Research Council Centre for Drug Safety Science, Department Molecular and Clinical Pharmacology, University of Liverpool, Liverpool L69 3GE, United Kingdom
| | - Ana Alfirevic
- Medical Research Council Centre for Drug Safety Science, Department Molecular and Clinical Pharmacology, University of Liverpool, Liverpool L69 3GE, United Kingdom
| | - Lisa Douglas
- Cheshire and Wirral Partnership National Health Service Foundation Trust, Chester CH2 1BQ, United Kingdom; and
| | - Rachel Mcloughlin
- Cheshire and Wirral Partnership National Health Service Foundation Trust, Chester CH2 1BQ, United Kingdom; and
| | - Edward Silva
- Mersey Care National Health Service Foundation Trust, Rathbone Low Secure Unit, Rathbone Hospital, Liverpool L13 4AW, United Kingdom
| | - B Kevin Park
- Medical Research Council Centre for Drug Safety Science, Department Molecular and Clinical Pharmacology, University of Liverpool, Liverpool L69 3GE, United Kingdom
| | - Munir Pirmohamed
- Medical Research Council Centre for Drug Safety Science, Department Molecular and Clinical Pharmacology, University of Liverpool, Liverpool L69 3GE, United Kingdom
| | - Dean J Naisbitt
- Medical Research Council Centre for Drug Safety Science, Department Molecular and Clinical Pharmacology, University of Liverpool, Liverpool L69 3GE, United Kingdom;
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11
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Geib T, Thulasingam M, Haeggström JZ, Sleno L. Investigation of Clozapine and Olanzapine Reactive Metabolite Formation and Protein Binding by Liquid Chromatography-Tandem Mass Spectrometry. Chem Res Toxicol 2020; 33:2420-2431. [PMID: 32786547 DOI: 10.1021/acs.chemrestox.0c00191] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Drug-induced toxicity has, in many cases, been linked to oxidative metabolism resulting in the formation of reactive metabolites and subsequent covalent binding to biomolecules. Two structurally related antipsychotic drugs, clozapine (CLZ) and olanzapine (OLZ), are known to form similar nitrenium ion reactive metabolites. CLZ-derived reactive metabolites have been linked to agranulocytosis and hepatotoxicity. We have studied the oxidative metabolism of CLZ and OLZ as well as two known metabolites of CLZ, desmethyl-CLZ (DCLZ), and CLZ-N-oxide (CLZ-NO), using in vitro rat liver microsomal (RLM) incubations with glutathione (GSH) trapping of reactive metabolites and liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS). Reactive metabolite binding to selected standard peptides and recombinant purified human proteins was also evaluated. Bottom-up proteomics was performed using two complementary proteases, prefractionation of peptides followed by LC-HRMS/MS for elucidating modifications of target proteins. Induced RLM was selected to form reactive metabolites enzymatically to assess the complex profile of reactive metabolite structures and their binding potential to standard human proteins. Multiple oxidative metabolites and several different GSH adducts were found for CLZ and OLZ. Modification sites were characterized on human glutathione S-transferase (hGST) alpha 1 (OLZ-modified at Cys112), hGST mu 2 (OLZ at Cys115), and hGST pi (CLZ, DCLZ, CLZ-NO and OLZ at Cys170), human microsomal GST 1 (hMGST1, CLZ and OLZ at Cys50), and human serum albumin (hSA, CLZ at Cys34). Furthermore, two modified rat proteins, microsomal GST 1 (CLZ and OLZ at Cys50) and one CYP (OLZ-modified, multiple possible isoforms), from RLM background were also characterized. In addition, direct effects of the reactive metabolite modifications on proteins were observed, including differences in protease cleavage specificity, chromatographic behavior, and charge-state distributions.
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Affiliation(s)
- Timon Geib
- Chemistry Department, Université du Québec à Montréal, Montréal, Québec H2X 2J6, Canada
| | - Madhuranayaki Thulasingam
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, 171 77 Solna, Sweden
| | - Jesper Z Haeggström
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, 171 77 Solna, Sweden
| | - Lekha Sleno
- Chemistry Department, Université du Québec à Montréal, Montréal, Québec H2X 2J6, Canada
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12
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Abstract
Wider use of clozapine, one of the most effective antipshychotic drugs, is precluded by its propensity to cause agranulocytosis. Currently, clozapine is used for treatment-resistant schizophrenia, with mandatory blood count monitoring for the duration of treatment. Agranulocytosis occurs in up to 0.8% of patients and presents a significant medical challenge, despite decreasing mortality rates. In this paper, we review the epidemiology of clozapine-induced agranulocytosis (CLIA), advances in identifying genetic risk factors, and the preventive measures to reduce the risk of CLIA. We discuss the pathogenesis of CLIA, which, despite receiving considerable scientific attention, has not been fully elucidated. Finally, we address the clinical management and suggest the approach to clozapine re-challenge in patients with a previous episode of neutropenia. With a significant proportion of clozapine recipients in Western hemisphere being Black, we comment on the importance of recognizing benign ethnic neutropenia as a potential impediment to clozapine administration. This review aims to aid haematologists and psychiatrists to jointly manage neutropenia and agranulocytosis caused by clozapine.
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Affiliation(s)
- Aleksandar Mijovic
- Department of Haematological Medicine, King's College Hospital, London, SE5 9RS, UK.
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13
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Abstract
Neutrophils are a critical part of the body’s defense system to prevent serious bacterial and fungal infections. Neutropenia is a term which is defined by the absolute neutrophil counts (ANC) < 1,500 cells/µL, and it becomes clinically significant when the level falls below 500 cells/µL. The risk of morbidity and mortality increases considerably when the levels fall below 200. In some ethnicities, the neutropenia is chronic and is frequently seen on routine outpatient visits. On the other hand, transient neutropenia is associated with a transient drop in the neutrophil count and many of the underlying causes are reversible. Patients and their families, as well as some clinicians, express great concern for neutropenia, leading to a multitude of tests and emergency room visits. In this review, we discuss the causes of both chronic and transient neutropenia. Also, we have given special emphasis on the mechanism of neutropenia and management of transient neutropenia.
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Affiliation(s)
- Navdeep Singh
- Hospice and Palliative Care Medicine, North Shore Long Island Jewish Hospital, Brooklyn, USA
| | - Sandeep Singh Lubana
- Hematology and Medical Oncology, State University of New York Downstate Medical Center, Brooklyn, USA
| | - Lech Dabrowski
- Hematology and Medical Oncology, State University of New York Downstate Medical Center, Brooklyn, USA
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Legge SE, Walters JT. Genetics of clozapine-associated neutropenia: recent advances, challenges and future perspective. Pharmacogenomics 2019; 20:279-290. [PMID: 30767710 PMCID: PMC6563116 DOI: 10.2217/pgs-2018-0188] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Clozapine is the only effective antipsychotic for treatment-resistant schizophrenia but remains widely under prescribed, at least in part due to its potential to cause agranulocytosis and neutropenia. In this article, we provide an overview of the current understanding of the genetics of clozapine-associated agranulocytosis and neutropenia. We now know that the genetic etiology of clozapine-associated neutropenia is complex and is likely to involve variants from several genes including HLA-DQB1, HLA-B and SLCO1B3/SLCO1B7. We describe recent findings relating to the Duffy-null genotype and its association with benign neutropenia in individuals with African ancestry. Further advances will come from sequencing studies, large, cross-population studies and in understanding the molecular mechanisms underlying these associations.
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Affiliation(s)
- Sophie E Legge
- MRC Centre for Neuropsychiatric Genetics & Genomics, Division of Psychological Medicine & Clinical Neurosciences, School of Medicine, Cardiff University, Cardiff, CF24 4HQ, UK
| | - James Tr Walters
- MRC Centre for Neuropsychiatric Genetics & Genomics, Division of Psychological Medicine & Clinical Neurosciences, School of Medicine, Cardiff University, Cardiff, CF24 4HQ, UK
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15
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Dickens D, Rädisch S, Chiduza GN, Giannoudis A, Cross MJ, Malik H, Schaeffeler E, Sison-Young RL, Wilkinson EL, Goldring CE, Schwab M, Pirmohamed M, Nies AT. Cellular Uptake of the Atypical Antipsychotic Clozapine Is a Carrier-Mediated Process. Mol Pharm 2018; 15:3557-3572. [PMID: 29944835 DOI: 10.1021/acs.molpharmaceut.8b00547] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The weak base antipsychotic clozapine is the most effective medication for treating refractory schizophrenia. The brain-to-plasma concentration of unbound clozapine is greater than unity, indicating transporter-mediated uptake, which has been insufficiently studied. This is important, because it could have a significant impact on clozapine's efficacy, drug-drug interaction, and safety profile. A major limitation of clozapine's use is the risk of clozapine-induced agranulocytosis/granulocytopenia (CIAG), which is a rare but severe hematological adverse drug reaction. We first studied the uptake of clozapine into human brain endothelial cells (hCMEC/D3). Clozapine uptake into cells was consistent with a carrier-mediated process, which was time-dependent and saturable ( Vmax = 3299 pmol/million cells/min, Km = 35.9 μM). The chemical inhibitors lamotrigine, quetiapine, olanzapine, prazosin, verapamil, indatraline, and chlorpromazine reduced the uptake of clozapine by up to 95%. This could in part explain the in vivo interactions observed in rodents or humans for these compounds. An extensive set of studies utilizing transporter-overexpressing cell lines and siRNA-mediated transporter knockdown in hCMEC/D3 cells showed that clozapine was not a substrate of OCT1 (SLC22A1), OCT3 (SLC22A3), OCTN1 (SLC22A4), OCTN2 (SLC22A5), ENT1 (SLC29A1), ENT2 (SLC29A2), and ENT4/PMAT (SLC29A4). In a recent genome-wide analysis, the hepatic uptake transporters SLCO1B1 (OATP1B1) and SLCO1B3 (OATP1B3) were identified as additional candidate transporters. We therefore also investigated clozapine transport into OATP1B-transfected cells and found that clozapine was neither a substrate nor an inhibitor of OATP1B1 and OATP1B3. In summary, we have identified a carrier-mediated process for clozapine uptake into brain, which may be partly responsible for clozapine's high unbound accumulation in the brain and its drug-drug interaction profile. Cellular clozapine uptake is independent from currently known drug transporters, and thus, molecular identification of the clozapine transporter will help to understand clozapine's efficacy and safety profile.
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Affiliation(s)
- David Dickens
- Department of Molecular and Clinical Pharmacology , University of Liverpool , Liverpool L69 3GL , U.K
| | - Steffen Rädisch
- Department of Molecular and Clinical Pharmacology , University of Liverpool , Liverpool L69 3GL , U.K
| | - George N Chiduza
- Department of Molecular and Clinical Pharmacology , University of Liverpool , Liverpool L69 3GL , U.K
| | - Athina Giannoudis
- Department of Molecular and Clinical Cancer Medicine , University of Liverpool , Liverpool L69 3BX , U.K
| | - Michael J Cross
- Department of Molecular and Clinical Pharmacology , University of Liverpool , Liverpool L69 3GL , U.K
| | - Hassan Malik
- Liverpool Hepatobiliary Unit , University Hospital Aintree , Liverpool L9 7AL , U.K
| | - Elke Schaeffeler
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology , 70376 Stuttgart , Germany.,University Tübingen , Tübingen , Germany
| | - Rowena L Sison-Young
- Department of Molecular and Clinical Pharmacology , University of Liverpool , Liverpool L69 3GL , U.K
| | - Emma L Wilkinson
- Department of Molecular and Clinical Pharmacology , University of Liverpool , Liverpool L69 3GL , U.K
| | - Christopher E Goldring
- Department of Molecular and Clinical Pharmacology , University of Liverpool , Liverpool L69 3GL , U.K
| | - Matthias Schwab
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology , 70376 Stuttgart , Germany.,Department of Clinical Pharmacology , University Hospital Tübingen , 72076 Tubingen , Germany.,Department of Pharmacy and Biochemistry , University Tübingen , 72076 Tübingen , Germany
| | - Munir Pirmohamed
- Department of Molecular and Clinical Pharmacology , University of Liverpool , Liverpool L69 3GL , U.K
| | - Anne T Nies
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology , 70376 Stuttgart , Germany.,University Tübingen , Tübingen , Germany
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16
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De Berardis D, Rapini G, Olivieri L, Di Nicola D, Tomasetti C, Valchera A, Fornaro M, Di Fabio F, Perna G, Di Nicola M, Serafini G, Carano A, Pompili M, Vellante F, Orsolini L, Martinotti G, Di Giannantonio M. Safety of antipsychotics for the treatment of schizophrenia: a focus on the adverse effects of clozapine. Ther Adv Drug Saf 2018; 9:237-256. [PMID: 29796248 PMCID: PMC5956953 DOI: 10.1177/2042098618756261] [Citation(s) in RCA: 112] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 01/10/2018] [Indexed: 12/15/2022] Open
Abstract
Clozapine, a dibenzodiazepine developed in 1961, is a multireceptorial atypical antipsychotic approved for the treatment of resistant schizophrenia. Since its introduction, it has remained the drug of choice in treatment-resistant schizophrenia, despite a wide range of adverse effects, as it is a very effective drug in everyday clinical practice. However, clozapine is not considered as a top-of-the-line treatment because it may often be difficult for some patients to tolerate as some adverse effects can be particularly bothersome (i.e. sedation, weight gain, sialorrhea etc.) and it has some other potentially dangerous and life-threatening side effects (i.e. myocarditis, seizures, agranulocytosis or granulocytopenia, gastrointestinal hypomotility etc.). As poor treatment adherence in patients with resistant schizophrenia may increase the risk of a psychotic relapse, which may further lead to impaired social and cognitive functioning, psychiatric hospitalizations and increased treatment costs, clozapine adverse effects are a common reason for discontinuing this medication. Therefore, every effort should be made to monitor and minimize these adverse effects in order to improve their early detection and management. The aim of this paper is to briefly summarize and provide an update on major clozapine adverse effects, especially focusing on those that are severe and potentially life threatening, even if most of the latter are relatively uncommon.
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Affiliation(s)
- Domenico De Berardis
- National Health Service, Department of Mental Health, Psychiatric Service of Diagnosis and Treatment, ‘G. Mazzini’ Hospital, p.zza Italia 1, 64100 Teramo, Italy
| | - Gabriella Rapini
- National Health Service, Department of Mental Health, Psychiatric Service of Diagnosis and Treatment, ‘G. Mazzini’ Hospital, Teramo, Italy
| | - Luigi Olivieri
- National Health Service, Department of Mental Health, Psychiatric Service of Diagnosis and Treatment, ‘G. Mazzini’ Hospital, Teramo, Italy
| | - Domenico Di Nicola
- National Health Service, Department of Mental Health, Psychiatric Service of Diagnosis and Treatment, ‘G. Mazzini’ Hospital, Teramo, Italy
| | - Carmine Tomasetti
- Polyedra Research Group, Teramo, Italy Department of Neuroscience, Reproductive Science and Odontostomatology, School of Medicine ‘Federico II’ Naples, Naples, Italy
| | - Alessandro Valchera
- Polyedra Research Group, Teramo, Italy Villa S. Giuseppe Hospital, Hermanas Hospitalarias, Ascoli Piceno, Italy
| | - Michele Fornaro
- Department of Neuroscience, Reproductive Science and Odontostomatology, School of Medicine ‘Federico II’ Naples, Naples, Italy
| | - Fabio Di Fabio
- Polyedra Research Group, Teramo, Italy Department of Neurology and Psychiatry, Sapienza University of Rome, Rome, Italy
| | - Giampaolo Perna
- Hermanas Hospitalarias, FoRiPsi, Department of Clinical Neurosciences, Villa San Benedetto Menni, Albese con Cassano, Como, Italy Department of Psychiatry and Neuropsychology, University of Maastricht, Maastricht, The Netherlands Department of Psychiatry and Behavioral Sciences, Leonard Miller School of Medicine, University of Miami, Florida, USA
| | - Marco Di Nicola
- Institute of Psychiatry and Psychology, Catholic University of Sacred Heart, Rome, Italy
| | - Gianluca Serafini
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, Section of Psychiatry, University of Genoa, Genoa, Italy
| | - Alessandro Carano
- National Health Service, Department of Mental Health, Psychiatric Service of Diagnosis and Treatment, Hospital ‘Madonna Del Soccorso’, San Benedetto del Tronto, Italy
| | - Maurizio Pompili
- Department of Neurosciences, Mental Health and Sensory Organs, Suicide Prevention Center, Sant’Andrea Hospital, Sapienza University of Rome, Rome, Italy
| | - Federica Vellante
- Department of Neuroscience, Imaging and Clinical Science, Chair of Psychiatry, University ‘G. D’Annunzio’, Chieti, Italy
| | - Laura Orsolini
- Polyedra Research Group, Teramo, Italy Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, Herts, UK
| | - Giovanni Martinotti
- Department of Neuroscience, Imaging and Clinical Science, Chair of Psychiatry, University ‘G. D’Annunzio’, Chieti, Italy
| | - Massimo Di Giannantonio
- Department of Neuroscience, Imaging and Clinical Science, Chair of Psychiatry, University ‘G. D’Annunzio’, Chieti, Italy
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18
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Curtis BR. Non-chemotherapy drug-induced neutropenia: key points to manage the challenges. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2017; 2017:187-193. [PMID: 29222255 PMCID: PMC6142577 DOI: 10.1182/asheducation-2017.1.187] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Non-chemotherapy idiosyncratic drug-induced neutropenia (IDIN) is a relatively rare but potentially fatal disorder that occurs in susceptible individuals, with an incidence of 2.4 to 15.4 cases per million population. Affected patients typically experience severe neutropenia within several weeks to several months after first exposure to a drug, and mortality is ∼5%. The drugs most frequently associated with IDIN include metamizole, clozapine, sulfasalazine, thiamazole, carbimazole, amoxicillin, cotrimoxazole, ticlopidine, and valganciclovir. The idiosyncratic nature of IDIN, the lack of mouse models and diagnostic testing, and its low overall incidence make rigorous studies to elucidate possible mechanisms exceptionally difficult. An immune mechanism for IDIN involving neutrophil destruction by hapten (drug)-specific antibodies and drug-induced autoantibodies is frequently suggested, but strong supporting evidence is lacking. Although laboratory testing for neutrophil drug-dependent antibodies is rarely performed because of the complexity and low sensitivity of tests currently in use, these assays could possibly be enhanced by using reactive drug metabolites in place of the parent drug. Patients typically experience acute, severe neutropenia, or agranulocytosis (<0.5 × 109 neutrophils/L) and symptoms of fever, chills, sore throat, and muscle and joint pain. Diagnosis can be difficult, but timely recognition is critical because if left untreated, there is an increase in mortality. Expanded studies of the production and mechanistic role of reactive drug metabolites, genetic associations, and improved animal models of IDIN are essential to further our understanding of this important disorder.
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Affiliation(s)
- Brian R Curtis
- Blood Research Institute, BloodCenter of Wisconsin, Milwaukee, WI
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19
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Genome-wide common and rare variant analysis provides novel insights into clozapine-associated neutropenia. Mol Psychiatry 2017; 22:1502-1508. [PMID: 27400856 PMCID: PMC5065090 DOI: 10.1038/mp.2016.97] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 05/10/2016] [Accepted: 05/17/2016] [Indexed: 01/31/2023]
Abstract
The antipsychotic clozapine is uniquely effective in the management of schizophrenia; however, its use is limited by its potential to induce agranulocytosis. The causes of this, and of its precursor neutropenia, are largely unknown, although genetic factors have an important role. We sought risk alleles for clozapine-associated neutropenia in a sample of 66 cases and 5583 clozapine-treated controls, through a genome-wide association study (GWAS), imputed human leukocyte antigen (HLA) alleles, exome array and copy-number variation (CNV) analyses. We then combined associated variants in a meta-analysis with data from the Clozapine-Induced Agranulocytosis Consortium (up to 163 cases and 7970 controls). In the largest combined sample to date, we identified a novel association with rs149104283 (odds ratio (OR)=4.32, P=1.79 × 10-8), intronic to transcripts of SLCO1B3 and SLCO1B7, members of a family of hepatic transporter genes previously implicated in adverse drug reactions including simvastatin-induced myopathy and docetaxel-induced neutropenia. Exome array analysis identified gene-wide associations of uncommon non-synonymous variants within UBAP2 and STARD9. We additionally provide independent replication of a previously identified variant in HLA-DQB1 (OR=15.6, P=0.015, positive predictive value=35.1%). These results implicate biological pathways through which clozapine may act to cause this serious adverse effect.
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Potential Mechanisms of Hematological Adverse Drug Reactions in Patients Receiving Clozapine in Combination With Proton Pump Inhibitors. J Psychiatr Pract 2017; 23:114-120. [PMID: 28291036 DOI: 10.1097/pra.0000000000000223] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Clozapine is a second-generation antipsychotic which has proven efficacy in treating the symptoms of schizophrenia. Although clozapine therapy is associated with a number of adverse drug reactions, it is frequently used. One of the most common adverse drug reactions is gastroesophageal reflux disease which is an indication for treatment with proton pump inhibitors (PPIs). Coadministration of clozapine and PPIs increases the risk of hematological adverse drug reactions, including neutropenia and agranulocytosis. The mechanism in idiosyncratic agranulocytosis is not dose related and involves either a direct toxic or an immune-allergic effect. It is suspected that the clozapine metabolites nitrenium ion and N-desmethylclozapine may cause apoptosis or impair growth of granulocytes. Formation of N-desmethylclozapine is correlated with activity of the cytochrome P450 enzymes 1A2 and 3A4 (CYP1A2 and CYP3A4). Nitrenium ion is produced by the flavin-containing monooxygenase system of leukocytes. A drug interaction between clozapine and a PPI is a consequence of the induction of common metabolic pathways either by the PPI or clozapine. Findings to date suggest that indirect induction of flavin-containing monooxygenase by omeprazole through the aryl hydrocarbon receptor increases the expression of the enzyme mRNA and in the long term may cause the increase in activity. Moreover, induction of CYP1A2, especially by omeprazole and lansoprazole, may increase the serum concentration of N-desmethylclozapine, which can accumulate in lymphocytes and may achieve toxic levels. Another hypothesis that may explain hematological adverse drug reactions is competitive inhibition of CYP2C19, which may contribute to increased serum concentrations of toxic metabolites.
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Clozapine-induced agranulocytosis: Evidence for an immune-mediated mechanism from a patient-specific in-vitro approach. Toxicol Appl Pharmacol 2017; 316:10-16. [DOI: 10.1016/j.taap.2016.12.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 11/18/2016] [Accepted: 12/05/2016] [Indexed: 11/21/2022]
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Abstract
To rechallenge with clozapine for a patient who previously has experienced neutropenia or leucopenia or during clozapine treatment is a difficult clinical decision. Herein, we analyzed the results of such a rechallenge in 19 patients. We analyzed all the reports, from the database of the pharmacovigilance department of the Argentine National Administration of Drugs, Foods, and Medical Devices, of patients who were rechallenged with clozapine after a leucopenia or a neutropenia. Nineteen cases of rechallenge after leucopenia or neutropenia were reported between 1996 and 2014. One third of the patients re-exposed to clozapine developed a new hematologic adverse reaction. The second blood dyscrasia was less severe in 83% of the cases and had a shorter median latency as compared with the first (8 weeks vs 182 weeks, P = 0.0045). There were no significant differences for demographic and clinical characteristics of patients who developed a second dyscrasia as compared with those who did not. The present study shows that almost 70% of the patients rechallenged with clozapine after a leucopenia or a neutropenia did not develop a new hematological adverse effect, whereas the remaining 30% had a faster but less serious neutropenia.
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Abstract
Drug-induced lupus erythematosus (DILE) is a lupus-like illness that has been recognized as an entity under environmentally-induced lupus erythematosus, where other agents such as physical (ultra-violet irradiation), chemical (heavy metals, aromatic amines) and food products (alfalfa sprouts) have been implicated. DILE has been accepted as a side effect of therapy with over 80 drugs since its first description in association with sulfadiazine in 1945. The epidemiology and clinical course of SLE and DILE differ markedly and prognosis is generally favourable in the latter although occasional lifethreatening cases have been reported in the literature. Constant pharmacovigilance is crucial for prompt diagnosis and cessation of offending therapy offers the best outcome. This review discusses the clinical presentation, diagnosis of DILE as well as provides an update on postulated pathogenic mechanisms and an overview of implicated drugs.
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Affiliation(s)
- S Vasoo
- Division of Rheumatology, Department of Medicine, National University Hospital, Singapore.
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24
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Jiang L, Wu X, Wang S, Chen SH, Zhou H, Wilson B, Jin CY, Lu RB, Xie K, Wang Q, Hong JS. Clozapine metabolites protect dopaminergic neurons through inhibition of microglial NADPH oxidase. J Neuroinflammation 2016; 13:110. [PMID: 27184631 PMCID: PMC4869380 DOI: 10.1186/s12974-016-0573-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 05/06/2016] [Indexed: 01/02/2023] Open
Abstract
Background Clozapine, an atypical antipsychotic medication, has been effectively used to treat refractory schizophrenia. However, the clinical usage of clozapine is limited due to a high incidence of neutropenia or agranulocytosis. We previously reported that clozapine protected dopaminergic neurons through inhibition of microglial activation. The purpose of this study was to explore the neuroprotective effects of clozapine metabolites clozapine N-oxide (CNO) and N-desmethylclozapine (NDC), as well as their propensity to cause neutropenia. Methods The primary midbrain neuron-glia culture was applied to detect the neuroprotective and anti-inflammatory effect of clozapine and its metabolites in lipopolysaccharide (LPS) and MPP+-induced toxicity. And the subsequent mechanism was demonstrated by gp91phox mutant cell cultures as well as microgliosis cell lines. In vivo, to confirm the neuroprotective effect of clozapine and CNO, we measured the dopaminergic neuronal loss and rotarod motor deficits in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-generated mouse Parkinson’s disease (PD) model. The neutropenia or agranulocytosis of clozapine and its metabolites was illustrated by white blood cell count of the treated mice. Results We found that, in midbrain neuron-glia cultures, CNO and NDC were more potent than clozapine in protecting dopaminergic neurons against LPS and MPP+-induced toxicity. CNO and NDC-afforded neuroprotection was linked to inhibition of microglia-mediated neuroinflammation, as demonstrated by abolished neuroprotection in microglia-depleted cultures and their capacity of inhibiting LPS-induced release of proinflammatory factors from activated microglia. NADPH oxidase (NOX2) was subsequently recognized as the main target of CNO and NDC since genetic ablation of gp91phox, the catalytic subunit of NOX2, abolished their neuroprotective effects. CNO and NDC inhibited NOX2 activation through interfering with the membrane translocation of the NOX2 cytosolic subunit, p47phox. The neuroprotective effects of CNO were further verified in vivo as shown by attenuation of dopaminergic neurodegeneration, motor deficits, and reactive microgliosis in MPTP-generated mouse PD model. More importantly, unlike clozapine, CNO did not lower the white blood cell count. Conclusions Altogether, our results show that clozapine metabolites elicited neuroprotection through inactivation of microglia by inhibiting NOX2. The robust neuroprotective effects and lack of neutropenia suggest that clozapine metabolites may be promising candidates for potential therapy for neurodegenerative diseases. Electronic supplementary material The online version of this article (doi:10.1186/s12974-016-0573-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lulu Jiang
- Neuropharmacology Section, Laboratory of Neurobiology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, 27709, USA.,Institute of Toxicology, School of Public Health, Shandong University, Jinan, Shandong, 250012, China
| | - Xuefei Wu
- Department of Physiology, Dalian Medical University, Dalian, Liaoning, 116044, China
| | - Shuo Wang
- Institute of Toxicology, School of Public Health, Shandong University, Jinan, Shandong, 250012, China
| | - Shih-Heng Chen
- Neuropharmacology Section, Laboratory of Neurobiology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, 27709, USA
| | - Hui Zhou
- Department of Occupational and Environmental Health, School of Public Health, Peking University, Beijing, 100191, China
| | - Belinda Wilson
- Neuropharmacology Section, Laboratory of Neurobiology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, 27709, USA
| | - Chun-Yang Jin
- Center for Drug Discovery, Research Triangle Institute, Research Triangle Park, NC, 27709, USA
| | - Ru-Band Lu
- Department of Psychiatry, Institute of Behavioral Medicine, Institute of Allied Health Sciences and Addiction Research Center, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, 70101, Taiwan.,Center for Neuropsychiatric Research, National Health Research Institutes, Miaoli, 35035, Taiwan
| | - Keqin Xie
- Institute of Toxicology, School of Public Health, Shandong University, Jinan, Shandong, 250012, China.
| | - Qingshan Wang
- Department of Occupational and Environmental Health, School of Public Health, Dalian Medical University, Dalian, Liaoning, 116044, China.
| | - Jau-Shyong Hong
- Neuropharmacology Section, Laboratory of Neurobiology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, 27709, USA
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Abstract
Clozapine is the antipsychotic of choice for treatment-resistant schizophrenia and is linked to a need for mandatory hematological monitoring. Besides agranulocytosis, other hematological aberrations have resulted in premature termination in some cases. Considering clozapine's role in immunomodulation, we proceeded to investigate the impact of clozapine on the following 3 main hematological cell lines: red blood cells, platelets, white blood cells (WBCs), and its differential counts. Data were extracted from patients initiated on clozapine between January 2009 and December 2010 at a single hospital. Patients with a preclozapine complete blood count, who were receiving clozapine during the 1-year follow-up period, were included in the present investigation. Counts of red blood cells, platelets, WBC, and its differential including neutrophils, lymphocytes, monocytes, eosinophils, and basophils were extracted and trajectories plotted. One hundred one patients were included in this study and 66 remained on clozapine at the end of 1 year. There was a synchronized but transient increase in WBC, neutrophils, monocytes, eosinophils, basophils, and platelets beginning as early as the first week of clozapine treatment. There were no cases of agranulocytosis reported in this sample, and five developed neutropenia. A spike in neutrophils immediately preceded the onset of neutropenia in three of the five. The cumulative incidence rates were 48.9% for neutrophilia, 5.9% for eosinophilia, and 3% each for thrombocytosis and thrombocytopenia. Early hematological aberrations are visible across a range of cell lines, primarily of the myeloid lineage. These disturbances are transient and are probably related to clozapine's immunomodulatory properties. We do not suggest discontinuing clozapine as a consequence of the observed aberrations.
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de With SAJ, Pulit SL, Wang T, Staal WG, van Solinge WW, de Bakker PIW, Ophoff RA. Genome-wide association study of lymphoblast cell viability after clozapine exposure. Am J Med Genet B Neuropsychiatr Genet 2015; 168B:116-22. [PMID: 25656473 DOI: 10.1002/ajmg.b.32287] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 11/25/2014] [Indexed: 12/20/2022]
Abstract
Clozapine is an antipsychotic drug with proven efficacy in treatment-resistant schizophrenia but also known to induce potentially lethal agranulocytosis (CIA) in 1% of patients. Genetic factors are likely to play a role in the molecular basis of CIA. We explored an in vitro system to study the genetic susceptibility of CIA. Cell viability was measured in 90 lymphoblast cell lines exposed to a series of increasing concentrations of clozapine for 48 hr. Quantitative trait measures of cell viability as well as area under the survival curve were used in a linear mixed model for genome-wide association analyses. The estimated heritability of clozapine-induced cell viability reduction in these cell lines is h2=0.76. No genome-wide significant association was observed after correction for multiple testing. Two independent loci with nominal evidence of association were observed at 30× clinical clozapine concentration: rs2709505 (P=1.41×10(-8)) in an intron of MDFIC and rs10457252 (P=1.79×10(-8)) located in a gene desert at chromosome 6q21. We identified one locus (rs1293970) near PRG4 that was consistently associated for all separate concentration analyses at P<5×10(-5). PRG4 encodes hemangiopoietin, a growth stimulator for hematopoietic stem cells. No evidence was observed for involvement of the MHC region. Our results demonstrate that clozapine-induced viability reduction in lymphoblast cell lines is a heritable, polygenic trait. Thus, in vitro models of CIA might be a useful tool for future discovery of genetic risk factors, although larger sample sizes will be required to unambiguously identify these loci.
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Affiliation(s)
- S A J de With
- UCLA Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, California; Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, The Netherlands
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Abstract
INTRODUCTION Drug-induced lupus (DIL) refers to an idiosyncratic side effect of numerous, apparently unrelated, medications, in which symptoms overlap with those of systemic lupus erythematosus. DIL is reversible by discontinuation of the medication. The etiological mechanism underlying DIL is linked to the inherent susceptibility of the adaptive immune system to lapse into auto-reactivity. AREAS COVERED Clinical and laboratory features of DIL will be compared with those of idiopathic systemic lupus and with other types of drug reactions with overlapping features. Formerly commonly-used drugs conferred very high risk of developing DIL, although the probability of developing DIL has not been established with most lupus-inducing drugs. Pharmacological or physiochemical properties of the parent compounds are uninformative, but the importance of reactive drug metabolites in initiating autoimmunity will be discussed. As with most systemic autoimmune diseases, the pathogenesis of DIL is complex and obscure. The role of complement and human leukocyte allotypes as well as drug acetylator phenotype inform the underlying mechanism, and several of these non-mutually exclusive concepts will be described. EXPERT OPINION The pros and cons of proposed mechanisms for DIL will be discussed in the context of current understanding of autoimmunity and immune tolerance to self.
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Affiliation(s)
- Robert L Rubin
- University of New Mexico Health Sciences Center, Department of Molecular Genetics and Microbiology , Albuquerque, NM 87131 , USA +1 505 272 4640 ; +1 505 272 9550 ;
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Johnston A, Uetrecht J. Current understanding of the mechanisms of idiosyncratic drug-induced agranulocytosis. Expert Opin Drug Metab Toxicol 2014; 11:243-57. [DOI: 10.1517/17425255.2015.985649] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Abstract
Agranulocytosis is defined as an absolute neutrophil count less than 100/mm(3) in association with infectious disease. The risk of agranulocytosis is 0.38% of all clozapine treated cases and there is a relatively lesser incidence in Indian population. The risk of clozapine-induced agranulocytosis and neutropenia is highest in the first 6 months and higher in the initial 18 months after the onset of treatment. There have been very few reports of neutropenia and agranulocytosis after this period. There have so far been no reports of late onset clozapine induced agranulocytosis has been reported from India. A case of late onset clozapine induced agranulocytosis with possible mechanism of the same is reported.
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Affiliation(s)
- Rajmohan Velayudhan
- Department of Psychiatry, MES Medical College, Perinthalmanna, Kerala, India
| | - Sushil Kakkan
- Department of Psychiatry, KMCT Medical College, Calicut, Kerala, India
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Lobach AR, Uetrecht J. Clozapine promotes the proliferation of granulocyte progenitors in the bone marrow leading to increased granulopoiesis and neutrophilia in rats. Chem Res Toxicol 2014; 27:1109-19. [PMID: 24968143 DOI: 10.1021/tx500184c] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Clozapine is an atypical antipsychotic that is limited in its use due to the risk of idiosyncratic agranulocytosis. The bone marrow is suspected to be the site of the reaction, and indirect measurements in patients suggest that neutrophil production and maturation are altered in the marrow by clozapine. Specifically, the majority of patients have elevated neutrophil counts at the start of treatment, often paired with increased serum granulocyte-colony stimulating factor (G-CSF). Employing a rat model of clozapine treatment, we set out to determine if the neutrophilia observed at the start of treatment is characteristic of G-CSF-associated bone marrow stimulation. Female Sprague-Dawley rats were treated with 30 mg/kg/day of clozapine for 10 days, and sustained neutrophilia was evident after 1 week of treatment paired with spikes in G-CSF. Within the bone marrow, clozapine was found to induce proliferation of the granulocyte progenitor colonies as measured by a methylcellulose assay. This led to elevated granulopoiesis observed by H&E and myeloperoxidase staining of bone marrow slices. Increased release of neutrophils from the marrow to the circulation was measured through 5-bromo-2'-deoxyuridine labeling in vivo, and these neutrophils appeared to be less mature based on (a) a decrease in the nuclear lobe count and (b) increased expression of surface CD62L. Furthermore, faster transit of the neutrophils through the marrow was suggested by a shift toward elevated numbers of neutrophils in the bone marrow maturation pool and increased CD11b and CD18 staining on the less mature neutrophils residing in the marrow. Taken together, these data indicate that clozapine stimulates the bone marrow to produce more neutrophils in a manner that is characteristic of endogenous G-CSF stimulation, and it is consistent with the inflammatory response observed in patients treated with clozapine.
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Affiliation(s)
- Alexandra R Lobach
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, and ‡Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto , 144 College Street, Toronto, Ontario M5S 3M2, Canada
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Abstract
Antipsychotic drugs (APDs) can have a profound effect on the human body that extends well beyond our understanding of their neuropsychopharmacology. Some of these effects manifest themselves in peripheral blood lymphocytes, and in some cases, particularly in clozapine treatment, result in serious complications. To better understand the molecular biology of APD action in lymphocytes, we investigated the influence of chlorpromazine, haloperidol and clozapine in vitro, by microarray-based gene and microRNA (miRNA) expression analysis. JM-Jurkat T-lymphocytes were cultured in the presence of the APDs or vehicle alone over 2 wk to model the early effects of APDs on expression. Interestingly both haloperidol and clozapine appear to regulate the expression of a large number of genes. Functional analysis of APD-associated differential expression revealed changes in genes related to oxidative stress, metabolic disease and surprisingly also implicated pathways and biological processes associated with neurological disease consistent with current understanding of the activity of APDs. We also identified miRNA-mRNA interaction associated with metabolic pathways and cell death/survival, all which could have relevance to known side effects of APDs. These results indicate that APDs have a significant effect on expression in peripheral tissue that relate to both known mechanisms as well as poorly characterized side effects.
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Reconstitution of the interplay between cytochrome P450 and human glutathione S-transferases in clozapine metabolism in yeast. Toxicol Lett 2013; 222:247-56. [DOI: 10.1016/j.toxlet.2013.07.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 07/22/2013] [Accepted: 07/24/2013] [Indexed: 01/10/2023]
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Glucuronidation of the second-generation antipsychotic clozapine and its active metabolite N-desmethylclozapine. Potential importance of the UGT1A1 A(TA)₇TAA and UGT1A4 L48V polymorphisms. Pharmacogenet Genomics 2012; 22:561-76. [PMID: 22565219 DOI: 10.1097/fpc.0b013e328354026b] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Clozapine (CLZ) is an FDA approved second-generation antipsychotic for refractory schizophrenia, and glucuronidation is an important pathway in its metabolism. The aim of this study was to fully characterize the CLZ glucuronidation pathway and examine whether polymorphisms in active glucuronidating enzymes could contribute to variability in CLZ metabolism. METHODS Cell lines overexpressing wild-type or variant uridine diphosphate-glucuronosyltransferase (UGT) enzymes were used to determine which UGTs show activity against CLZ and its major active metabolite N-desmethylclozapine (dmCLZ). Human liver microsomes (HLM) were used to compare hepatic glucuronidation activity against the UGT genotype. RESULTS Several UGTs including 1A1 and 1A4 were active against CLZ; only UGT1A4 showed activity against dmCLZ. UGT1A1 showed a 2.1-fold (P <0.0001) higher V(max)/K(M) for formation of the CLZ-N⁺-glucuronide than UGT1A4; UGT1A4 was the only UGT for which CLZ-5-N-glucuronide kinetics could be determined. The UGT1A4(24Pro/48Val) variant showed a 5.2-, 2.0-, and 3.4-fold (P < 0.0001 for all) higher V(max)/K(M) for the formation of CLZ-5-N-glucuronide, CLZ-N⁺-glucuronide, and dmCLZ-5-N-glucuronide, respectively, as compared with that of wild-type UGT1A4(24Pro/48Leu). There was a 37% (P< 0.05) decrease in the rate of CLZ-N⁺-glucuronide formation in HLM with the UGT1A1 (*28/*28)/UGT1A4 (*1/*1) genotype, and a 2.2- and 1.8-fold (P < 0.05 for both) increase in the formation of CLZ-5-N-glucuronide and CLZ-N⁺-glucuronide in UGT1A1 (*1/*1)/UGT1A4 (*3/*3) HLM compared with UGT1A1 (*1/*1)/UGT1A4 (*1/*1) HLM. The UGT1A1*28 allele was a significant (P = 0.045) predictor of CLZ-N⁺-glucuronide formation; the UGT1A4*3 allele was a significant (P < 0.0001) predictor of CLZ-5-N-glucuronide and dmCLZ-glucuronide formation. CONCLUSION These data suggest that the UGT1A1*28 and UGT1A4*3 alleles contribute significantly to the interindividual variability in CLZ and dmCLZ metabolism.
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Abstract
Abstract
Neutropenia is defined as the reduction in the absolute number of neutrophils in the blood circulation. Acute neutropenia is a relatively frequent finding, whereas disorders of production of neutrophils are quite rare. Acute neutropenia is often well tolerated and normalizes rapidly. Neutropenia arising as a result of underlying hematologic disorders is far more significant. Such a patient may be at risk for infectious complications and will likely require a thorough investigation. Acute neutropenia evolves over a few days and occurs when neutrophil use is rapid and production is impaired. Chronic neutropenia may last for 3 months or longer and is a result of reduced production, increased destruction, or excessive splenic sequestration of neutrophils. Neutropenia may be classified by whether it arises secondarily to causes extrinsic to BM myeloid cells, which is common; as an acquired disorder of myeloid progenitor cells, which is less frequent; or as an intrinsic defect arising from impaired proliferation and maturation of myeloid progenitor cells in the BM, which is rare. Severe neutropenia with absolute neutrophil counts below 500/μL increases susceptibility to bacterial or fungal infections. Multiple disorders of severe congenital neutropenia have been found by the discovery of genetic defects affecting differentiation, adhesion, and apoptosis of neutrophil precursors. Elucidation of the multiple genetic defects have provided insight into the biology of the cell involving membrane structures, secretory vesicles, mitochondrial metabolism, ribosome biogenesis, transcriptional regulation, and cytoskeletal dynamics, as well as the risk for myelodysplasia and acute myeloid leukemia.
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Berk V, Demiraslan H, Berk E, Karaca H, Inanc M, Bozkurt O, Ozkan M. Moxifloxacin-associated neutropenia. SCANDINAVIAN JOURNAL OF INFECTIOUS DISEASES 2012; 45:415-6. [PMID: 23151058 DOI: 10.3109/00365548.2012.738937] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A 32-y-old woman presented with pneumonia. Treatment was started with moxifloxacin. On day 2 of moxifloxacin treatment the patient developed neutropenia. After discontinuing the moxifloxacin, neutrophil counts were normal on day 4. Clinicians should be aware of the possibility of this adverse effect in patients treated with moxifloxacin.
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Affiliation(s)
- Veli Berk
- Deparment of Medical Oncology, Erciyes University Medical School, Kayseri,Turkey.
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Immunomodulatory effects of clozapine and their clinical implications: what have we learned so far? Schizophr Res 2012; 140:204-13. [PMID: 22831769 DOI: 10.1016/j.schres.2012.06.020] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 06/02/2012] [Accepted: 06/19/2012] [Indexed: 01/24/2023]
Abstract
Clozapine remains the drug of choice for treatment resistant schizophrenia, but is associated with potentially life threatening side effects, including agranulocytosis and myocarditis. Immunological mechanisms may be involved in the development of these side effects or in the unique antipsychotic efficacy in subgroups of schizophrenia patients. This systematic review presents the immunomodulatory effects of clozapine from human in vitro and in vivo studies and relates these findings to the developments of adverse and therapeutic effects of clozapine. Several studies confirm the immunomodulatory actions of clozapine, but only few studies investigated their relationship to the unique adverse and therapeutic effects of clozapine. During the first month of clozapine treatment, up to 50% of patients develop fever and flu like symptoms, which is seemingly driven by increased cytokines. Within the same time period, the risk of side-effects with a suspected immunological mechanism peaks. Patients developing fever during the first weeks of treatment should have a thorough physical examination, and measurements of white blood cell count, absolute neutrophil count, ECG, C-reactive protein, creatinine kinase, and troponin to exclude infection, agranulocytosis, myocarditis and neuroleptic malignant syndrome. To what degree the unique antipsychotic efficacy of clozapine in subgroups of schizophrenia patients is related to its immunomodulatory effects has not been studied. Research relating the immunomodulatory actions of clozapine and its early markers to clinically relevant adverse and therapeutic outcomes is hoped to provide new leads for the understanding of the pathophysiology of schizophrenia and aid the development of novel treatment targets.
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Chen ML, Tsai TC, Wang LK, Lin YY, Tsai YM, Lee MC, Tsai FM. Clozapine inhibits Th1 cell differentiation and causes the suppression of IFN-γ production in peripheral blood mononuclear cells. Immunopharmacol Immunotoxicol 2012; 34:686-94. [DOI: 10.3109/08923973.2011.651535] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Ng W, Lobach AR, Zhu X, Chen X, Liu F, Metushi IG, Sharma A, Li J, Cai P, Ip J, Novalen M, Popovic M, Zhang X, Tanino T, Nakagawa T, Li Y, Uetrecht J. Animal Models of Idiosyncratic Drug Reactions. CURRENT CONCEPTS IN DRUG METABOLISM AND TOXICOLOGY 2012; 63:81-135. [DOI: 10.1016/b978-0-12-398339-8.00003-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Chen ML, Tsai TC, Wang LK, Lin YY, Tsai YM, Lee MC, Tsai FM. Risperidone modulates the cytokine and chemokine release of dendritic cells and induces TNF-α-directed cell apoptosis in neutrophils. Int Immunopharmacol 2011; 12:197-204. [PMID: 22154580 DOI: 10.1016/j.intimp.2011.11.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 11/07/2011] [Accepted: 11/23/2011] [Indexed: 10/14/2022]
Abstract
Antipsychotic drugs (APDs) that bind mainly to the dopamine D2 receptor or the type II 5-HT receptor have been used to ease the symptoms of schizophrenia. Several studies have reported that APDs can also regulate the immune response. Dendritic cells (DCs) are the major antigen-presenting cells in the immune system. DCs can release 5-HT and dopamine to modulate T-cell activation and differentiation. In this study, we use the monocyte-derived DCs to investigate the drug effects of typical APD (haloperidol) and atypical APD (risperidone) on DCs in vitro. Our studies revealed that only risperidone but not haloperidol affected the cytokine and chemokine production of mature DCs. Risperidone increased the production of IL-10 and MDC as well as the proinflammatory cytokines, such as IL-6, IL-8, and TNF-α, but decreased the production of IP-10 and IL-12. Furthermore, the exposure of DCs to risperidone led to lower IFN-γ production by T-cells. The results suggested that risperidone can modulate the DCs' immune function by inhibiting the potent Th1 cytokines and increasing the potent Th2 cytokines. In addition, the production of TNF-α by risperidone-treated mature DCs will induce the death of neutrophils.
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Affiliation(s)
- Mao-Liang Chen
- Department of Research, Buddhist Tzu Chi General Hospital, Taipei Branch, New Taipei City, Taiwan
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Arakelyan A, Zakharyan R, Khoyetsyan A, Poghosyan D, Aroutiounian R, Mrazek F, Petrek M, Boyajyan A. Functional characterization of the complement receptor type 1 and its circulating ligands in patients with schizophrenia. BMC Clin Pathol 2011; 11:10. [PMID: 21867543 PMCID: PMC3176470 DOI: 10.1186/1472-6890-11-10] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 08/25/2011] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Whereas the complement system alterations contribute to schizophrenia, complement receptors and regulators are little studied. We investigated complement receptor type 1 (CR1) expression on blood cells, the levels of circulating immune complexes (CIC) containing ligands of CR1, C1q complement protein and fragments of C3 complement protein (C1q-CIC, C3d-CIC), and CR1 C5507G functional polymorphism in schizophrenia patients and controls. RESULTS We found an increased C1q-CIC level and CR1 expression on blood cells, elevated number of CR1 positive erythrocytes and reduced number of CR1 positive lymphocytes and monocytes in patients compared to controls. No difference in the levels of C3d-CIC between groups was observed. Higher CR1 expression on erythrocytes in CC genotype versus CG+GG for both groups was detected, whereas no difference was observed for other cell populations. Our results indicated that schizophrenia is associated with the increased CR1 expression and C1q-CIC level. CONCLUSIONS Our study for the first time indicated that schizophrenia is associated with the increased CR1 expression and C1q-CIC level. Further studies in other ethnic groups are needed to replicate these findings.
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Affiliation(s)
- Arsen Arakelyan
- Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia, 7 Hasratyan St., 0014, Yerevan, Armenia
| | - Roksana Zakharyan
- Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia, 7 Hasratyan St., 0014, Yerevan, Armenia
- Faculty of Medicine and Dentistry, Palacky University, 6 I. P. Pavlova St., 775 20, Olomouc, Czech Republic
| | - Aren Khoyetsyan
- Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia, 7 Hasratyan St., 0014, Yerevan, Armenia
| | - David Poghosyan
- Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia, 7 Hasratyan St., 0014, Yerevan, Armenia
| | - Rouben Aroutiounian
- Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia, 7 Hasratyan St., 0014, Yerevan, Armenia
- Biological Faculty of Yerevan State University, 1 Al. Manoogian St., 0025, Yerevan, Armenia
| | - Frantisek Mrazek
- Faculty of Medicine and Dentistry, Palacky University, 6 I. P. Pavlova St., 775 20, Olomouc, Czech Republic
| | - Martin Petrek
- Faculty of Medicine and Dentistry, Palacky University, 6 I. P. Pavlova St., 775 20, Olomouc, Czech Republic
| | - Anna Boyajyan
- Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia, 7 Hasratyan St., 0014, Yerevan, Armenia
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Exploring off-targets and off-systems for adverse drug reactions via chemical-protein interactome--clozapine-induced agranulocytosis as a case study. PLoS Comput Biol 2011; 7:e1002016. [PMID: 21483481 PMCID: PMC3068927 DOI: 10.1371/journal.pcbi.1002016] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Accepted: 01/25/2011] [Indexed: 12/20/2022] Open
Abstract
In the era of personalized medical practice, understanding the genetic basis of patient-specific adverse drug reaction (ADR) is a major challenge. Clozapine provides effective treatments for schizophrenia but its usage is limited because of life-threatening agranulocytosis. A recent high impact study showed the necessity of moving clozapine to a first line drug, thus identifying the biomarkers for drug-induced agranulocytosis has become important. Here we report a methodology termed as antithesis chemical-protein interactome (CPI), which utilizes the docking method to mimic the differences in the drug-protein interactions across a panel of human proteins. Using this method, we identified HSPA1A, a known susceptibility gene for CIA, to be the off-target of clozapine. Furthermore, the mRNA expression of HSPA1A-related genes (off-target associated systems) was also found to be differentially expressed in clozapine treated leukemia cell line. Apart from identifying the CIA causal genes we identified several novel candidate genes which could be responsible for agranulocytosis. Proteins related to reactive oxygen clearance system, such as oxidoreductases and glutathione metabolite enzymes, were significantly enriched in the antithesis CPI. This methodology conducted a multi-dimensional analysis of drugs' perturbation to the biological system, investigating both the off-targets and the associated off-systems to explore the molecular basis of an adverse event or the new uses for old drugs. Idiosyncratic drug reactions (IDR) generally cannot be identified until after a drug is taken by a large population, but usually result in restricted use or withdrawal. Clozapine provides the most effective treatment for schizophrenia but its use is limited because of a life-threatening IDR, i.e., the agranulocytosis. A high impact clinical study demonstrated the necessity of moving clozapine from 3rd line to 1st line drug; therefore, intensive research has aimed at identifying genes responsible for clozapine-induced agranulocytosis (CIA). Olanzapine, an analog of clozapine, has much lower incidence of agranulocytosis. Based on this phenomenon, we proposed an in silico methodology termed as antithesis chemical-protein interactome (CPI), which mimics the differences in the drug-protein interactions of the two drugs across a panel of human proteins. e.g., HSPA1A was identified to be targeted by clozapine not olanzapine. Furthermore, the gene expression of the HSPA1A-related gene system was also found up-regulated after clozapine treatment. This approach can examine the system's perturbation in terms of both the off-target and the off-system's interaction with the drug, providing theoretical basis for decoding the adverse drug reactions or the new uses for old drugs.
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Zhang X, Zhang X, Liu F, Chen X, Zhu X, Uetrecht J. Involvement of the immune system in idiosyncratic drug reactions. Drug Metab Pharmacokinet 2010; 26:47-59. [PMID: 21084762 DOI: 10.2133/dmpk.dmpk-10-rv-085] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
There is strong evidence that most idiosyncratic drug reactions (IDRs) are immune-mediated and are caused by reactive metabolites of a drug rather than by the drug itself. Several hypotheses have been proposed by which a drug could induce an immune response. The major hypotheses are the hapten hypothesis and the danger hypothesis; however, the characteristics and spectrum of IDRs are different with different drugs, and this likely reflects mechanistic differences; therefore, no one hypothesis is likely to explain all IDRs. Some IDRs appear to involve epigenetic effects, direct activation of antigen-presenting cells, or disturbing the normal balance of the immune system. It has been suggested that many cases of idiosyncratic liver injury are not immune-mediated, and other mechanisms such as mitochondrial injury may be involved. It is essential that any hypothesis be consistent with the clinical characteristics of the IDR. Although the characteristics of most idiosyncratic liver injury do not suggest that mitochondria are the major target, it is quite possible that milder mitochondrial injury could stimulate an immune-mediated reaction. The observation that IDRs can vary widely among different drugs and different patients is most easily explained by an immune mechanism in which the target of the immune response is different.
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Affiliation(s)
- Xiaochu Zhang
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada.
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Heiser P, Sommer O, Schmidt AJ, Clement HW, Hoinkes A, Hopt UT, Schulz E, Krieg JC, Dobschütz E. Effects of antipsychotics and vitamin C on the formation of reactive oxygen species. J Psychopharmacol 2010; 24:1499-504. [PMID: 19282419 DOI: 10.1177/0269881109102538] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
There is evidence that reactive oxygen species (ROS) are involved in the pathophysiology of psychiatric disorders such as schizophrenia. Indirect biochemical alterations of ROS formation have been shown for patients treated with antipsychotics as well as for untreated patients. Only one study measured directly the ROS formation after treatment with antipsychotics by using electron spin resonance spectroscopy. The aim of the present examination was to demonstrate the effects of haloperidol, clozapine and olanzapine in concentrations of 18, 90 and 180 μg/mL on the formation of ROS in the whole blood of rats by using electron spin resonance spectroscopy after incubation for 30 min. To test the protective capacity of vitamin C we incubated the highest concentration of each drug with vitamin C (1 mM). Under all treatment conditions, olanzapine led to a significantly higher formation of ROS compared with control conditions, whereas in the cases of haloperidol and clozapine the two higher concentrations induced a significantly enhanced formation of ROS. Vitamin C reduced the ROS production of all drugs tested and for haloperidol and clozapine the level of significance was reached. Our study demonstrated that antipsychotics induce the formation of ROS in the whole blood of rats, which can be reduced by the application of vitamin C.
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Affiliation(s)
- P Heiser
- Department of Child and Adolescent Psychiatry, Albert-Ludwigs-University, Freiburg, Germany.
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Iverson S, Kautiainen A, Ip J, Uetrecht JP. Effect of Clozapine on Neutrophil Kinetics in Rabbits. Chem Res Toxicol 2010; 23:1184-91. [DOI: 10.1021/tx100035k] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Suzanne Iverson
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario M5S 3M2
| | - Antti Kautiainen
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario M5S 3M2
| | - Julia Ip
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario M5S 3M2
| | - Jack P. Uetrecht
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario M5S 3M2
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Mishra AC, Mohanty B. Effects of lactational exposure of olanzapine and risperidone on hematology and lymphoid organs histopathology: A comparative study in mice neonates. Eur J Pharmacol 2010; 634:170-7. [DOI: 10.1016/j.ejphar.2010.02.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2009] [Revised: 01/21/2010] [Accepted: 02/08/2010] [Indexed: 02/01/2023]
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Li CR, Chung YC, Park TW, Yang JC, Kim KW, Lee KH, Hwang IK. Clozapine-induced tardive dyskinesia in schizophrenic patients taking clozapine as a first-line antipsychotic drug. World J Biol Psychiatry 2010; 10:919-24. [PMID: 19995222 DOI: 10.1080/15622970802481895] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVE Clozapine causes few extrapyramidal symptoms and is recommended as a treatment drug for severe tardive dyskinesia (TD). However, several case reports have suggested that clozapine could also cause TD. We investigated whether clozapine used as a first-line antipsychotic drug can cause TD. METHOD We identified 101 patients at Yanbian Socio-Mental Hospital and Yanbian Brain Hospital in China who had received clozapine as a primary antipsychotic drug since their first episode of illness and evaluated the prevalence rate, type, and severity of TD using the Extrapyramidal Symptoms Rating Scale (ESRS). The criterion for TD was a score of > or = 3 on one item or 2 on two or more items of the ESRS. RESULTS The mean age and duration of illness of the patients were 38.93+/-8.36 and 12.88+/-6.90 years, respectively. The mean duration of clozapine treatment was 12.10+/-6.26 years. The prevalence of TD was 3.96% (4/101). Compared to patients without TD, patients with TD had a long duration of illness and clozapine treatment; all had the orolingual type of TD. TD was relatively mild, with a mean score of 4.75, and tended to accentuate with an activation procedure of rapid pronation and supination of the hands. CONCLUSIONS These results suggest that clozapine may cause TD; however, the prevalence is low and the severity is relatively mild, with no or mild self-reported discomfort. Therefore, we recommend that regular examination for TD using the activation procedure should be performed in patients who use clozapine on a long-term basis.
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Affiliation(s)
- Chun-Rong Li
- Department of Psychiatry, Chonbuk National University Medical School & Institute for Medical Sciences, Jeonju, South Korea
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Abstract
Numerous medications and other xenobiotics are capable of producing adverse reactions (ADRs) affecting red cells, platelets or neutrophils. Occasionally, more than one blood element is affected simultaneously. As with all drug reactions, some side effects are a direct consequence of a known pharmacologic action of the drug and are dose-dependent; others occur sporadically and relatively independent of dose. The latter ("idiosyncratic") reactions are unpredictable and, in general, have no known underlying genetic basis. Many are antibody-mediated, as would be expected since cellular immune effector cells have little direct access to circulating blood cells. In this chapter, we will discuss idiosyncratic drug reactions affecting blood and blood forming tissues with an emphasis on those thought to be immune-mediated.
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Affiliation(s)
- Richard H Aster
- Blood Research Institute, Blood Center of Wisconsin, 2178 Watertown Plank Rd, Milwaukee, WI 53201, USA.
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Abstract
Drug-induced lupus erythematosus (DILE) is defined as an entity characterized by clinical manifestations and immunopathological serum findings similar to those of idiopathic lupus but which is temporally related to continuous drug exposure and resolves after discontinuation of the offending drug. Similar to idiopathic lupus, DILE can be divided into systemic lupus erythematosus (SLE), subacute cutaneous lupus erythematosus (SCLE) and chronic cutaneous lupus erythematosus (CCLE). Based on the literature review and retrospective analysis of our case series, we focused on the dermatological aspects of DILE. The cutaneous features of drug-induced SLE are protean, including particularly purpura, erythema nodosum and photosensitivity as well as the skin lesions characterizing both urticarial and necrotizing vasculitis. The typical laboratory profile of systemic DILE consists of positive antinuclear antibodies (ANA) and antihistone antibodies, the latter being regarded as the serum marker of this subset. The drugs most frequently implicated in the development of systemic DILE are hydralazine, procainamide, isoniazid and minocycline. Drug-induced SCLE usually presents with annular polycyclic or papulosquamous cutaneous manifestations as in the idiopathic form, but blisters or targetoid lesions mimicking erythema multiforme cannot rarely be associated. The clinical presentation is often generalized, with involvement of the lower legs that are usually spared in idiopathic SCLE. ANA and anti-Ro/SSA antibodies are usually present, whereas antihistone antibodies are uncommonly found. Drugs associated with SCLE include particularly calcium channel blockers, angiotensin-converting enzyme inhibitors, thiazide diuretics, terbinafine and the recently reported tumour necrosis factor (TNF)-α antagonists. Drug-induced CCLE is very rarely described in the literature and usually refers to fluorouracile agents or TNF-α antagonists. The picture is characterized by the occurrence of classic discoid lesions, but aspects of lupus tumidus can occasionally develop. ANA are demonstrated in around two-thirds of the cases. Management of DILE is based on the withdrawal of the offending drug. Topical and/or systemic corticosteroids and other immunosuppressive agents should be reserved for resistant cases.
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Affiliation(s)
- AV Marzano
- Department of Anesthesiology, Intensive Care and Dermatological Sciences, University of Milan, Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Milan, Italy
| | - P Vezzoli
- Department of Anesthesiology, Intensive Care and Dermatological Sciences, University of Milan, Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Milan, Italy
| | - C Crosti
- Department of Anesthesiology, Intensive Care and Dermatological Sciences, University of Milan, Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Milan, Italy
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Loeffler S, Fehsel K, Krieger K, Henning U, Klimke A. Inhibition of p38-mitogen-activated protein kinase may protect from clozapine-induced agranulocytosis. World J Biol Psychiatry 2009; 5:54-5. [PMID: 15048637 DOI: 10.1080/15622970410029909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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