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Qubad M, Dupont G, Hahn M, Martin SS, Puntmann V, Nagel E, Reif A, Bittner RA. When, Why and How to Re-challenge Clozapine in Schizophrenia Following Myocarditis. CNS Drugs 2024; 38:671-696. [PMID: 38951464 DOI: 10.1007/s40263-024-01100-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/03/2024] [Indexed: 07/03/2024]
Abstract
Clozapine-induced myocarditis (CIM) is among the most important adverse events limiting the use of clozapine as the most effective treatment for schizophrenia. CIM necessitates the immediate termination of clozapine, often resulting in its permanent discontinuation with considerable detrimental effects on patients' psychopathology and long-term outcome. Consequently, a clozapine re-challenge after CIM is increasingly regarded as a viable alternative, with published reports indicating a success rate of approximately 60%. However, published cases of re-challenges after CIM remain limited. Here, we provide a narrative review of the current state of research regarding the epidemiology, pathophysiology, risk factors, diagnosis and clinical management of CIM as well as a synthesis of current recommendations for re-challenging patients after CIM. This includes a step-by-step guide for this crucial procedure based on the current evidence regarding the pathophysiology and risk factors for CIM. Slow dose titration regimes and addressing risk factors including concomitant valproate and olanzapine are crucial both to prevent CIM and to ensure a safe and successful re-challenge. Furthermore, we discuss the utility of C-reactive protein, troponin, N-terminal-pro hormone and brain natriuretic peptide, therapeutic drug-monitoring and cardiac magnetic resonance imaging for CIM screening and diagnosis as well as for post-CIM re-challenges.
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Affiliation(s)
- Mishal Qubad
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University Frankfurt, University Hospital, Frankfurt, Germany.
| | - Gabriele Dupont
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University Frankfurt, University Hospital, Frankfurt, Germany
| | - Martina Hahn
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University Frankfurt, University Hospital, Frankfurt, Germany
- Department of Mental Health, Varisano Hospital Frankfurt Hoechst, Frankfurt, Germany
| | - Simon S Martin
- Department of Radiology, Goethe University Frankfurt, University Hospital, Frankfurt, Germany
| | - Valentina Puntmann
- Department of Cardiology, Institute for Experimental and Translational Cardiovascular Imaging, Goethe University Frankfurt, University Hospital, Frankfurt, Germany
| | - Eike Nagel
- Department of Cardiology, Institute for Experimental and Translational Cardiovascular Imaging, Goethe University Frankfurt, University Hospital, Frankfurt, Germany
| | - Andreas Reif
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University Frankfurt, University Hospital, Frankfurt, Germany
| | - Robert A Bittner
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University Frankfurt, University Hospital, Frankfurt, Germany.
- Ernst Strüngmann Institute for Neuroscience (ESI) in Cooperation with Max Planck Society, Frankfurt, Germany.
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Karakuş F, Arzuk E, Ergüç A. Mitochondrial Impact of Organophosphate Pesticide-Induced Cardiotoxicity: An In Silico and In Vitro Study. Int J Toxicol 2024:10915818241261624. [PMID: 38897602 DOI: 10.1177/10915818241261624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Organophosphate pesticides are widely used; however, their use is limited due to neurotoxicity and, to a lesser extent, cardiotoxicity in humans. Given the high energy demands of cardiac muscle, which is characterized by a dense population of mitochondria, any damage to these organelles can exacerbate cardiotoxicity. This study aims to elucidate whether the cardiotoxic effects of organophosphate pesticides originate from mitochondrial dysfunction. To investigate this, in silico toxicogenomic analyses were performed using various tools, such as the Comparative Toxicogenomic Database, GeneMANIA, STRING, and Cytoscape. Results revealed that 11 out of the 13 WHO-recommended Class Ia organophosphate pesticides target genes associated with cardiotoxicity. Notably, three of these genes were mitochondrial, with catalase (CAT) being the common differentially expressed gene among parathion, methyl parathion, and phorate. Furthermore, protein-protein interaction analysis indicated a strong association between CAT and superoxide dismutase 2, mitochondrial (SOD2). Subsequently, isolated heart mitochondria were utilized to assess CAT and superoxide dismutase (SOD) activities in vitro. The findings demonstrated that at a concentration of 7.5 ng/µL, both methyl parathion and phorate significantly decreased CAT activity by approximately 35%. Moreover, phorate reduced total SOD and SOD2 activities by 17% and 19%, respectively, at the same concentration. In contrast, none of the three organophosphate pesticides induced the opening of the mitochondrial permeability transition pore. These results suggest that the reduction in CAT and SOD2 activities, critical antioxidant enzymes, leads to the accumulation of reactive oxygen species within mitochondria, ultimately resulting in mitochondrial damage. This mechanism likely underlies the observed cardiotoxicity induced by these organophosphate pesticides.
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Affiliation(s)
- Fuat Karakuş
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Van Yuzuncu Yil University, Van, Türkiye
| | - Ege Arzuk
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Ege University, İzmir, Türkiye
| | - Ali Ergüç
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, İzmir Kâtip Çelebi University, İzmir, Türkiye
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3
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Uwai Y, Nabekura T. Relationship Between Clozapine and Non-Hematological Malignant Tumors: A Pharmacovigilance Analysis Using the FDA Adverse Event Reporting System Database. Drugs Real World Outcomes 2024; 11:185-193. [PMID: 38556566 PMCID: PMC11176119 DOI: 10.1007/s40801-024-00417-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/18/2024] [Indexed: 04/02/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Clozapine shows higher efficacy against treatment-resistant schizophrenia than other antipsychotics. This study aimed to investigate whether clozapine is associated with the risk of non-hematological malignant tumors, utilizing the US Food and Drug Administration (FDA) Adverse Event Report System (FAERS) database. METHODS The records from the first quarter of 2004 to the third quarter of 2012 were used for disproportionality analysis, and patients who developed non-hematological malignant tumors were identified by the Standardized Medical Dictionary for Regulatory Activities Queries (SMQ). RESULTS Of the 3,641,281 patients with 12,401,586 reports of adverse drug events, 151,904 reports belonged to non-hematological malignant tumors (SMQ). We identified 1668 reports of non-hematological malignant tumors (SMQ) in clozapine users, and the reporting odds ratio (ROR) was calculated to be 1.28 (95% confidence interval (CI): 1.22-1.34). ROR (95% CI) for the relationship between clozapine and the risk of testis cancer was calculated as 10.94 (6.99-17.12), 9.87 (7.42-13.15) for gastrointestinal carcinoma, 7.48 (5.57-10.05) for metastatic lung cancer, 6.71 (4.52-9.97) for throat cancer, 6.12 (4.56-8.21) for metastases to the spine, 5.97 (5.30-6.72) for lung malignant neoplasm, 5.07 (3.69-6.95) for esophageal carcinoma, 1.88 (1.43-2.47) for colon cancer, and 1.65 (1.24-2.21) for metastases to the liver. Colon cancer, esophageal carcinoma, and throat cancer were predominantly reported in males, and metastases to the spine and liver were in females. CONCLUSION This study detected signals indicating a relationship between clozapine and certain non-hematological malignant tumors, utilizing the FAERS database. Despite the database relying on spontaneous reporting, the current results justify further investigation.
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Affiliation(s)
- Yuichi Uwai
- School of Pharmacy, Aichi Gakuin University, 1-100, Kusumoto, Chikusa, Nagoya, 464-8650, Japan.
| | - Tomohiro Nabekura
- School of Pharmacy, Aichi Gakuin University, 1-100, Kusumoto, Chikusa, Nagoya, 464-8650, Japan
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4
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Bo Y, Zhao X, Li L. Cardiotoxic effects of common and emerging drugs: role of cannabinoid receptors. Clin Sci (Lond) 2024; 138:413-434. [PMID: 38505994 DOI: 10.1042/cs20231156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 02/23/2024] [Accepted: 03/12/2024] [Indexed: 03/21/2024]
Abstract
Drug-induced cardiotoxicity has become one of the most common and detrimental health concerns, which causes significant loss to public health and drug resources. Cannabinoid receptors (CBRs) have recently achieved great attention for their vital roles in the regulation of heart health and disease, with mounting evidence linking CBRs with the pathogenesis and progression of drug-induced cardiotoxicity. This review aims to summarize fundamental characteristics of two well-documented CBRs (CB1R and CB2R) from aspects of molecular structure, signaling and their functions in cardiovascular physiology and pathophysiology. Moreover, we describe the roles of CB1R and CB2R in the occurrence of cardiotoxicity induced by common drugs such as antipsychotics, anti-cancer drugs, marijuana, and some emerging synthetic cannabinoids. We highlight the 'yin-yang' relationship between CB1R and CB2R in drug-induced cardiotoxicity and propose future perspectives for CBR-based translational medicine toward cardiotoxicity curation and clinical monitoring.
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Affiliation(s)
- Yiming Bo
- Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Xin Zhao
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Liliang Li
- Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
- Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai 200032, China
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5
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Ding Z, Jia H, Yang Z, Yao N, Wang Y. The cardiovascular toxicity of clozapine in embryonic zebrafish and RNA sequencing-based transcriptome analysis. J Appl Toxicol 2024; 44:175-183. [PMID: 37605992 DOI: 10.1002/jat.4530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 07/29/2023] [Accepted: 08/07/2023] [Indexed: 08/23/2023]
Abstract
Clozapine (CLZ) is the most prescribed medication for treating refractory schizophrenia but is associated with significant cardiovascular toxicity. This study aimed to investigate the cardiovascular toxicity induced by CLZ using zebrafish as a model animal. For this purpose, zebrafish developed to 80-h post-fertilization were exposed to different CLZ concentration solutions for 24 h followed by cardiac morphological observations in yolk sac edema, pericardial edema, and blood coagulation, in addition to increased SV-BA distance, functionally manifested as bradycardia, and decreased cardiac ejection fraction using the untreated embryos as control. At the same time, RNA sequencing was used to study the possible molecular mechanism of CLZ-induced cardiovascular toxicity. The results indicated that compared to the control group, the experimental groups possessed a total of 5888 differentially expressed genes (DEGs), where gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment of analysis indicated that DEGs were mainly enriched in the pathways related to ion channels. These findings may provide new insights and directions for the subsequent in-depth study of the molecular mechanism of CLZ-induced cardiovascular toxicity.
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Affiliation(s)
- Zijiao Ding
- Department of Pathology, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Huiting Jia
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Ziqian Yang
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Nan Yao
- Department of Pathology, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China
| | - Yunyun Wang
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
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6
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Tang X, Liu H, Rao R, Huang Y, Dong M, Xu M, Feng S, Shi X, Wang L, Wang Z, Zhou B. Modeling drug-induced mitochondrial toxicity with human primary cardiomyocytes. SCIENCE CHINA. LIFE SCIENCES 2024; 67:301-319. [PMID: 37864082 DOI: 10.1007/s11427-023-2369-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 05/16/2023] [Indexed: 10/22/2023]
Abstract
Mitochondrial toxicity induced by therapeutic drugs is a major contributor for cardiotoxicity, posing a serious threat to pharmaceutical industries and patients' lives. However, mitochondrial toxicity testing is not incorporated into routine cardiac safety screening procedures. To accurately model native human cardiomyocytes, we comprehensively evaluated mitochondrial responses of adult human primary cardiomyocytes (hPCMs) to a nucleoside analog, remdesivir (RDV). Comparison of their response to human pluripotent stem cell-derived cardiomyocytes revealed that the latter utilized a mitophagy-based mitochondrial recovery response that was absent in hPCMs. Accordingly, action potential duration was elongated in hPCMs, reflecting clinical incidences of RDV-induced QT prolongation. In a screen for mitochondrial protectants, we identified mitochondrial ROS as a primary mediator of RDV-induced cardiotoxicity. Our study demonstrates the utility of hPCMs in the detection of clinically relevant cardiac toxicities, and offers a framework for hPCM-based high-throughput screening of cardioprotective agents.
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Affiliation(s)
- Xiaoli Tang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China
| | - Hong Liu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China
| | - Rongjia Rao
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China
| | - Yafei Huang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China
| | - Mengqi Dong
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China
| | - Miaomiao Xu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China
| | - Shanshan Feng
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China
| | - Xun Shi
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China
| | - Li Wang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital Chinese Academy of Medical Sciences, Shenzhen, Shenzhen, 518020, China
| | - Zengwu Wang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China
- Department of Epidemiology, Cardiovascular Institute and Fuwai Hospital, Chinese Academy of Medical Science & Peking Union Medical College, Beijing, 100037, China
| | - Bingying Zhou
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100037, China.
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital Chinese Academy of Medical Sciences, Shenzhen, Shenzhen, 518020, China.
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7
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Kingston E, Tingle M, Bellissima BL, Helsby N, Burns K. CYP-catalysed cycling of clozapine and clozapine- N-oxide promotes the generation of reactive oxygen species in vitro. Xenobiotica 2024; 54:26-37. [PMID: 38108307 DOI: 10.1080/00498254.2023.2294473] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 12/10/2023] [Indexed: 12/19/2023]
Abstract
Clozapine is an effective atypical antipsychotic indicated for treatment-resistant schizophrenia, but is under-prescribed due to the risk of severe adverse drug reactions such as myocarditis.A mechanistic understanding of clozapine cardiotoxicity remains elusive.This study aimed to investigate the contribution of selected CYP isoforms to cycling between clozapine and its major circulating metabolites, N-desmethylclozapine and clozapine-N-oxide, with the potential for reactive species production.CYP supersome™-based in vitro techniques were utilised to quantify specific enzyme activity associated with clozapine, clozapine-N-oxide and N-desmethylclozapine metabolism.The formation of reactive species within each incubation were quantified, and known intermediates detected.CYP3A4 predominately catalysed clozapine-N-oxide formation from clozapine and was associated with concentration-dependent reactive species production, whereas isoforms favouring the N-desmethylclozapine pathway (CYP2C19 and CYP1A2) did not produce reactive species.Extrahepatic isoforms CYP2J2 and CYP1B1 were also associated with the formation of clozapine-N-oxide and N-desmethylclozapine but did not favour one metabolic pathway over another.Unique to this investigation is that various CYP isoforms catalyse clozapine-N-oxide reduction to clozapine.This process was associated with the concentration-dependent formation of reactive species with CYP3A4, CYP1B1 and CYP1A1 that did not correlate with known reactive intermediates, implicating metabolite cycling and reactive oxygen species in the mechanism of clozapine-induced toxicity.
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Affiliation(s)
- Ellen Kingston
- Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Auckland, New Zealand
| | - Malcolm Tingle
- Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Auckland, New Zealand
| | - Brandi L Bellissima
- Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Auckland, New Zealand
| | - Nuala Helsby
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland, New Zealand
| | - Kathryn Burns
- Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Auckland, New Zealand
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8
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De Simone G, Mazza B, Vellucci L, Barone A, Ciccarelli M, de Bartolomeis A. Schizophrenia Synaptic Pathology and Antipsychotic Treatment in the Framework of Oxidative and Mitochondrial Dysfunction: Translational Highlights for the Clinics and Treatment. Antioxidants (Basel) 2023; 12:antiox12040975. [PMID: 37107350 PMCID: PMC10135787 DOI: 10.3390/antiox12040975] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/05/2023] [Accepted: 04/13/2023] [Indexed: 04/29/2023] Open
Abstract
Schizophrenia is a worldwide mental illness characterized by alterations at dopaminergic and glutamatergic synapses resulting in global dysconnectivity within and between brain networks. Impairments in inflammatory processes, mitochondrial functions, energy expenditure, and oxidative stress have been extensively associated with schizophrenia pathophysiology. Antipsychotics, the mainstay of schizophrenia pharmacological treatment and all sharing the common feature of dopamine D2 receptor occupancy, may affect antioxidant pathways as well as mitochondrial protein levels and gene expression. Here, we systematically reviewed the available evidence on antioxidants' mechanisms in antipsychotic action and the impact of first- and second-generation compounds on mitochondrial functions and oxidative stress. We further focused on clinical trials addressing the efficacy and tolerability of antioxidants as an augmentation strategy of antipsychotic treatment. EMBASE, Scopus, and Medline/PubMed databases were interrogated. The selection process was conducted in respect of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Several mitochondrial proteins involved in cell viability, energy metabolism, and regulation of oxidative systems were reported to be significantly modified by antipsychotic treatment with differences between first- and second-generation drugs. Finally, antioxidants may affect cognitive and psychotic symptoms in patients with schizophrenia, and although the evidence is only preliminary, the results indicate that further studies are warranted.
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Affiliation(s)
- Giuseppe De Simone
- Section of Psychiatry, Laboratory of Translational and Molecular Psychiatry and Unit of Treatment-Resistant Psychosis, Department of Neuroscience, Reproductive Sciences, and Dentistry, University Medical School of Naples "Federico II", Via Pansini 5, 80131 Naples, Italy
| | - Benedetta Mazza
- Section of Psychiatry, Laboratory of Translational and Molecular Psychiatry and Unit of Treatment-Resistant Psychosis, Department of Neuroscience, Reproductive Sciences, and Dentistry, University Medical School of Naples "Federico II", Via Pansini 5, 80131 Naples, Italy
| | - Licia Vellucci
- Section of Psychiatry, Laboratory of Translational and Molecular Psychiatry and Unit of Treatment-Resistant Psychosis, Department of Neuroscience, Reproductive Sciences, and Dentistry, University Medical School of Naples "Federico II", Via Pansini 5, 80131 Naples, Italy
| | - Annarita Barone
- Section of Psychiatry, Laboratory of Translational and Molecular Psychiatry and Unit of Treatment-Resistant Psychosis, Department of Neuroscience, Reproductive Sciences, and Dentistry, University Medical School of Naples "Federico II", Via Pansini 5, 80131 Naples, Italy
| | - Mariateresa Ciccarelli
- Section of Psychiatry, Laboratory of Translational and Molecular Psychiatry and Unit of Treatment-Resistant Psychosis, Department of Neuroscience, Reproductive Sciences, and Dentistry, University Medical School of Naples "Federico II", Via Pansini 5, 80131 Naples, Italy
| | - Andrea de Bartolomeis
- Section of Psychiatry, Laboratory of Translational and Molecular Psychiatry and Unit of Treatment-Resistant Psychosis, Department of Neuroscience, Reproductive Sciences, and Dentistry, University Medical School of Naples "Federico II", Via Pansini 5, 80131 Naples, Italy
- UNESCO Chair on Health Education and Sustainable Development, University of Naples "Federico II", 80131 Naples, Italy
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9
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Genotoxicity of pyrrolizidine alkaloids in metabolically inactive human cervical cancer HeLa cells co-cultured with human hepatoma HepG2 cells. Arch Toxicol 2023; 97:295-306. [PMID: 36273350 PMCID: PMC9816206 DOI: 10.1007/s00204-022-03394-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 10/05/2022] [Indexed: 01/19/2023]
Abstract
Pyrrolizidine alkaloids (PAs) are secondary plant metabolites, which can be found as contaminant in various foods and herbal products. Several PAs can cause hepatotoxicity and liver cancer via damaging hepatic sinusoidal endothelial cells (HSECs) after hepatic metabolization. HSECs themselves do not express the required metabolic enzymes for activation of PAs. Here we applied a co-culture model to mimic the in vivo hepatic environment and to study PA-induced effects on not metabolically active neighbour cells. In this co-culture model, bioactivation of PA was enabled by metabolically capable human hepatoma cells HepG2, which excrete the toxic and mutagenic pyrrole metabolites. The human cervical epithelial HeLa cells tagged with H2B-GFP were utilized as non-metabolically active neighbours because they can be identified easily based on their green fluorescence in the co-culture. The PAs europine, riddelliine and lasiocarpine induced micronuclei in HepG2 cells, and in HeLa H2B-GFP cells co-cultured with HepG2 cells, but not in HeLa H2B-GFP cells cultured alone. Metabolic inhibition of cytochrome P450 enzymes with ketoconazole abrogated micronucleus formation. The efflux transporter inhibitors verapamil and benzbromarone reduced micronucleus formation in the co-culture model. Furthermore, mitotic disturbances as an additional genotoxic mechanism of action were observed in HepG2 cells and in HeLa H2B-GFP cells co-cultured with HepG2 cells, but not in HeLa H2B-GFP cells cultured alone. Overall, we were able to show that PAs were activated by HepG2 cells and the metabolites induced genomic damage in co-cultured HeLa cells.
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10
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Qubad M, Bittner RA. Second to none: rationale, timing, and clinical management of clozapine use in schizophrenia. Ther Adv Psychopharmacol 2023; 13:20451253231158152. [PMID: 36994117 PMCID: PMC10041648 DOI: 10.1177/20451253231158152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 01/24/2023] [Indexed: 03/31/2023] Open
Abstract
Despite its enduring relevance as the single most effective and important evidence-based treatment for schizophrenia, underutilization of clozapine remains considerable. To a substantial degree, this is attributable to a reluctance of psychiatrists to offer clozapine due to its relatively large side-effect burden and the complexity of its use. This underscores the necessity for continued education regarding both the vital nature and the intricacies of clozapine treatment. This narrative review summarizes all clinically relevant areas of evidence, which support clozapine's wide-ranging superior efficacy - for treatment-resistant schizophrenia (TRS) and beyond - and make its safe use eminently feasible. Converging evidence indicates that TRS constitutes a distinct albeit heterogeneous subgroup of schizophrenias primarily responsive to clozapine. Most importantly, the predominantly early onset of treatment resistance and the considerable decline in response rates associated with its delayed initiation make clozapine an essential treatment option throughout the course of illness, beginning with the first psychotic episode. To maximize patients' benefits, systematic early recognition efforts based on stringent use of TRS criteria, a timely offer of clozapine, thorough side-effect screening and management as well as consistent use of therapeutic drug monitoring and established augmentation strategies for suboptimal responders are crucial. To minimize permanent all-cause discontinuation, re-challenges after neutropenia or myocarditis should be considered. Owing to clozapine's unique efficacy, comorbid conditions including substance use and most somatic disorders should not dissuade but rather encourage clinicians to consider clozapine. Moreover, treatment decisions need to be informed by the late onset of clozapine's full effects, which for reduced suicidality and mortality rates may not even be readily apparent. Overall, the singular extent of its efficacy combined with the high level of patient satisfaction continues to distinguish clozapine from all other available antipsychotics.
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Affiliation(s)
- Mishal Qubad
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany
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11
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de Bartolomeis A, Vellucci L, Barone A, Manchia M, De Luca V, Iasevoli F, Correll CU. Clozapine's multiple cellular mechanisms: What do we know after more than fifty years? A systematic review and critical assessment of translational mechanisms relevant for innovative strategies in treatment-resistant schizophrenia. Pharmacol Ther 2022; 236:108236. [PMID: 35764175 DOI: 10.1016/j.pharmthera.2022.108236] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/21/2022] [Accepted: 06/21/2022] [Indexed: 12/21/2022]
Abstract
Almost fifty years after its first introduction into clinical care, clozapine remains the only evidence-based pharmacological option for treatment-resistant schizophrenia (TRS), which affects approximately 30% of patients with schizophrenia. Despite the long-time experience with clozapine, the specific mechanism of action (MOA) responsible for its superior efficacy among antipsychotics is still elusive, both at the receptor and intracellular signaling level. This systematic review is aimed at critically assessing the role and specific relevance of clozapine's multimodal actions, dissecting those mechanisms that under a translational perspective could shed light on molecular targets worth to be considered for further innovative antipsychotic development. In vivo and in vitro preclinical findings, supported by innovative techniques and methods, together with pharmacogenomic and in vivo functional studies, point to multiple and possibly overlapping MOAs. To better explore this crucial issue, the specific affinity for 5-HT2R, D1R, α2c, and muscarinic receptors, the relatively low occupancy at dopamine D2R, the interaction with receptor dimers, as well as the potential confounder effects resulting in biased ligand action, and lastly, the role of the moiety responsible for lipophilic and alkaline features of clozapine are highlighted. Finally, the role of transcription and protein changes at the synaptic level, and the possibility that clozapine can directly impact synaptic architecture are addressed. Although clozapine's exact MOAs that contribute to its unique efficacy and some of its severe adverse effects have not been fully understood, relevant information can be gleaned from recent mechanistic understandings that may help design much needed additional therapeutic strategies for TRS.
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Affiliation(s)
- Andrea de Bartolomeis
- Section of Psychiatry, Laboratory of Translational and Molecular Psychiatry and Unit of Treatment Resistant Psychosis, Department of Neuroscience, Reproductive Science and Dentistry, University Medical School of Naples "Federico II", Naples, Italy.
| | - Licia Vellucci
- Section of Psychiatry, Laboratory of Translational and Molecular Psychiatry and Unit of Treatment Resistant Psychosis, Department of Neuroscience, Reproductive Science and Dentistry, University Medical School of Naples "Federico II", Naples, Italy
| | - Annarita Barone
- Section of Psychiatry, Laboratory of Translational and Molecular Psychiatry and Unit of Treatment Resistant Psychosis, Department of Neuroscience, Reproductive Science and Dentistry, University Medical School of Naples "Federico II", Naples, Italy
| | - Mirko Manchia
- Section of Psychiatry, Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy; Department of Pharmacology, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | - Felice Iasevoli
- Section of Psychiatry, Laboratory of Translational and Molecular Psychiatry and Unit of Treatment Resistant Psychosis, Department of Neuroscience, Reproductive Science and Dentistry, University Medical School of Naples "Federico II", Naples, Italy
| | - Christoph U Correll
- The Zucker Hillside Hospital, Department of Psychiatry, Northwell Health, Glen Oaks, NY, USA; Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Department of Psychiatry and Molecular Medicine, Hempstead, NY, USA; Charité Universitätsmedizin Berlin, Department of Child and Adolescent Psychiatry, Berlin, Germany
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12
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Jackson KD, Argikar UA, Cho S, Crouch RD, Driscoll JP, Heck C, King L, Maw HH, Miller GP, Seneviratne HK, Wang S, Wei C, Zhang D, Khojasteh SC. Bioactivation and Reactivity Research Advances - 2021 year in review. Drug Metab Rev 2022; 54:246-281. [PMID: 35876116 DOI: 10.1080/03602532.2022.2097254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
This year's review on bioactivation and reactivity began as a part of the annual review on biotransformation and bioactivation led by Cyrus Khojasteh (Khojasteh et al., 2021, 2020, 2019, 2018, 2017; Baillie et al., 2016). Increased contributions from experts in the field led to the development of a stand alone edition for the first time this year focused specifically on bioactivation and reactivity. Our objective for this review is to highlight and share articles which we deem influential and significant regarding the development of covalent inhibitors, mechanisms of reactive metabolite formation, enzyme inactivation, and drug safety. Based on the selected articles, we created two sections: (1) reactivity and enzyme inactivation, and (2) bioactivation mechanisms and safety (Table 1). Several biotransformation experts have contributed to this effort from academic and industry settings.
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Affiliation(s)
- Klarissa D Jackson
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, Chapel Hill, NC 27599, USA
| | - Upendra A Argikar
- Non-clinical Development, Bill & Melinda Gates Medical Research Institute, Cambridge, MA, 02139, USA
| | - Sungjoon Cho
- Department of Drug Metabolism and Pharmacokinetics, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Rachel D Crouch
- Department of Pharmaceutical Sciences, Lipscomb University College of Pharmacy and Health Sciences, Nashville, TN, 37203, USA
| | - James P Driscoll
- Department of Drug Metabolism and Pharmacokinetics. Bristol Myers Squibb, Brisbane, CA, 94005, USA
| | - Carley Heck
- Medicine Design, Pfizer Worldwide Research, Development and Medical, Eastern Point Road, Groton, Connecticut, USA
| | - Lloyd King
- Department of DMPK, UCB Biopharma UK, 216 Bath Road, Slough, SL1 3WE, UK
| | - Hlaing Holly Maw
- Drug Metabolism and Pharmacokinetics, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT, 06877, USA
| | - Grover P Miller
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, 4301 W Markham St Slot 516, Little Rock, Arkansas, 72205, USA
| | - Herana Kamal Seneviratne
- Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Shuai Wang
- Department of Drug Metabolism and Pharmacokinetics, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - Cong Wei
- Drug Metabolism & Pharmacokinetics, Biogen Inc., Cambridge, MA, 02142, USA
| | - Donglu Zhang
- Department of Drug Metabolism and Pharmacokinetics, Genentech, Inc., South San Francisco, CA, 94080, USA
| | - S Cyrus Khojasteh
- Department of Drug Metabolism and Pharmacokinetics, Genentech, Inc., 1 DNA Way, MS412a, South San Francisco, CA, 94080, USA
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13
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Arzuk E, Tokdemir M, Orhan H. Mitochondrial versus microsomal bioactivation of paracetamol by human liver and kidney tissues. Toxicol Lett 2022; 363:36-44. [PMID: 35595037 DOI: 10.1016/j.toxlet.2022.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 05/11/2022] [Accepted: 05/13/2022] [Indexed: 11/17/2022]
Abstract
Mitochondria appeared to be a major target for paracetamol (PAR)-induced hepatotoxicity. Studies suggested that microsomal CYPs catalyse bioactivation of PAR to N-acetyl-p-benzoquinone imine (NAPQI), which alkylates mitochondrial proteins, and causes transmission of death signal from mitochondria to nucleus. We hypothesised that local formation of NAPQI within mitochondria seems more likely compared to the translocation of NAPQI. We therefore tested whether the formation of NAPQI may be catalysed by mitochondrial CYPs. Cellular fractions were isolated from human liver and kidney to compare the metabolic capacities. Liver and kidney mitochondria are capable to generate NAPQI. Mitochondrial CYP2E1 and CYP3A4 activities were comparable to the microsomal counterparts in both organs. Previously reported higher kidney microsomal CYP2E1 activity in men compared women were observed in mitochondrial CYP2E1 as well in the present study. On the other hand, no correlation between kidney CYP2E1 activity and quantity of NAPQI formation, as well as no induction on mitochondrial permeability transition pore (mPTP) opening by PAR in kidney mitochondria strongly suggested a different toxicity mechanism in this organ.
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Affiliation(s)
- Ege Arzuk
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Ege University, İzmir/Turkey
| | - Mehmet Tokdemir
- Department of Forensic Medicine, Faculty of Medicine, İzmir Kâtip Çelebi University, İzmir/Turkey
| | - Hilmi Orhan
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Ege University, İzmir/Turkey.
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14
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Vickers M, Ramineni V, Malacova E, Eriksson L, McMahon K, Moudgil V, Scott J, Siskind D. Risk factors for clozapine-induced myocarditis and cardiomyopathy: A systematic review and meta-analysis. Acta Psychiatr Scand 2022; 145:442-455. [PMID: 35067911 DOI: 10.1111/acps.13398] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/25/2021] [Accepted: 12/18/2021] [Indexed: 12/16/2022]
Abstract
OBJECTIVE Clozapine is the most effective medication for treatment-refractory schizophrenia, but it is associated with severe cardiac adverse events including myocarditis and cardiomyopathy. To aid treatment decision-making for clinicians, patients and their carers, we conducted a systematic review and meta-analysis to identify potential risk factors for clozapine-induced myocarditis and cardiomyopathy. METHODS A systematic search was conducted of PubMed, Embase, CINAHL, Web of Science, Cochrane and PsycInfo for studies reporting myocarditis and cardiomyopathy among people on clozapine and potential risk factors. We calculated pooled effect sizes on risk factors using a random-effects meta-analytic model. Risk of publication bias was assessed using the Newcastle-Ottawa scale. RESULTS Seven studies met the inclusion criteria, of which six studies had quantitative data included in the meta-analysis. The odds of clozapine-induced myocarditis increased with concurrent sodium valproate use (k = 6, n = 903, pooled OR 3.58, 95% CI 1.81-7.06), but were not significantly greater with the use of quetiapine, lithium or selective serotonin reuptake inhibitors. Our qualitative review identified conflicting results reported for increasing age and higher clozapine dose as risk factors for myocarditis. No other factors, including genetic risk, sex, ethnicity, smoking, alcohol, substance abuse or cardiometabolic disease, were associated with greater odds of myocarditis. No risk factors for cardiomyopathy were identified in the literature. CONCLUSION Concurrent use of sodium valproate increases the odds of clozapine-induced myocarditis. Thus, clinicians should consider the temporary cessation of sodium valproate during the initial titration phase of clozapine.
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Affiliation(s)
- Mark Vickers
- Metro North Mental Health Service, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.,Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia.,Faculty of Health, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Vinay Ramineni
- Metro North Mental Health Service, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.,Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - Eva Malacova
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Lars Eriksson
- Herston Health Sciences Library, University of Queensland, Brisbane, Queensland, Australia
| | - Kirsten McMahon
- Metro North Mental Health Service, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.,Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - Vikas Moudgil
- Metro North Mental Health Service, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.,Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - James Scott
- Metro North Mental Health Service, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.,QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Dan Siskind
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia.,Queensland Centre for Mental Health Research, Brisbane, Queensland, Australia.,Metro South Addiction and Mental Health Service, Brisbane, Queensland, Australia
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Metabolite Profiling of Clozapine in Patients Switching Versus Maintaining Treatment: A Retrospective Pilot Study. J Clin Psychopharmacol 2022; 42:470-474. [PMID: 35916581 PMCID: PMC9426748 DOI: 10.1097/jcp.0000000000001585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE/BACKGROUND Pharmacokinetics may be of relevance for the risk of clozapine discontinuation. We compared metabolite profiles, accounting for smoking habits, in patients switching versus maintaining clozapine treatment at therapeutic concentrations. METHODS/PROCEDURES Adult patients with clozapine serum levels above 1070 nmol/L (350 ng/mL) were retrospectively included from a Norwegian therapeutic drug monitoring service during 2018-2020. Inclusion criteria were (1) known smoking habits, (2) blood sample drawn within 10 to 30 hours after last clozapine intake, and (3) detectable levels of N -desmethylclozapine, clozapine -N -oxide, clozapine-5 N -glucuronide, or clozapine- N + - glucuronide. Patients comedicated with cytochrome P450 enzyme inducers, inhibitors, or valproic acid were excluded. The high-resolution mass spectrometry assay enabled detection of 21 clozapine metabolites. Metabolite profiles were compared between patients switching treatment (switchers), measured as clozapine being replaced by another antipsychotic drug in blood samples, versus maintaining clozapine treatment (nonswitchers) during the study period. FINDINGS/RESULTS Of the 84 patients fulfilling the study criteria, 7 patients (8.3%) were identified as clozapine switchers. After correcting for smoking habits, the clozapine-5 N -glucuronide/clozapine ratio was 69% lower ( P < 0.001), while the clozapine- N + -glucuronide/clozapine-5 N -glucuronide ratio was 143% higher ( P = 0.026), respectively, in switchers versus nonswitchers. The other metabolite ratios did not significantly differ between switchers and nonswitchers. IMPLICATIONS/CONCLUSIONS The present study found a significantly reduced 5 N -glucuronidation phenotype in patients switching from clozapine at therapeutic serum concentrations (>1070 nmol/L) to other antipsychotic drugs. This may indicate that glucuronidation, as a potential detoxification mechanism, is related to clozapine tolerability. However, the causality of this observation needs to be investigated in future studies with larger patient populations.
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Li XQ, Tang XR, Li LL. Antipsychotics cardiotoxicity: What's known and what's next. World J Psychiatry 2021; 11:736-753. [PMID: 34733639 PMCID: PMC8546771 DOI: 10.5498/wjp.v11.i10.736] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 07/08/2021] [Accepted: 09/02/2021] [Indexed: 02/06/2023] Open
Abstract
Chronic use of antipsychotic medications entails a dilemma between the benefit of alleviating psychotic symptoms and the risk of troubling, sometimes life-shortening adverse effects. Antipsychotic-induced cardiotoxicity is one of the most life-threatening adverse effects that raises widespread concerns. These cardiotoxic effects range from arrhythmia to heart failure in the clinic, with myocarditis/cardiomyopathy, ischemic injuries, and unexplained cardiac lesions as the pathological bases. Multiple mechanisms have been proposed to underlie antipsychotic cardiotoxicity. This review aims to summarize the clinical signs and pathological changes of antipsychotic cardiotoxicity and introduce recent progress in understanding the underlying mechanisms at both the subcellular organelle level and the molecular level. We also provide an up-to-date perspective on future clinical monitoring and therapeutic strategies for antipsychotic cardiotoxicity. We propose that third-generation antipsychotics or drug adjuvant therapy, such as cannabinoid receptor modulators that confer dual benefits — i.e., alleviating cardiotoxicity and improving metabolic disorders — deserve further clinical evaluation and marketing.
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Affiliation(s)
- Xiao-Qing Li
- Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Xin-Ru Tang
- Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Li-Liang Li
- Department of Forensic Medicine, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
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Thymoquinone reduces mitochondrial damage and death of cardiomyocytes induced by clozapine. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2021; 394:1675-1684. [PMID: 33937934 DOI: 10.1007/s00210-021-02095-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 04/20/2021] [Indexed: 10/21/2022]
Abstract
The generation of a reactive nitrenium ion by microsomal/mitochondrial cytochrome P450 (CYPs) from clozapine (CLZ) has been suggested as the main cause of cardiotoxicity by this drug. Previous studies indicated that thymoquinone (TQ) as an active constituent of Nigella sativa has pharmacological effects such as antioxidant, reactive oxygen species (ROS) scavenger, and inhibitory effect on CYPs enzymes. Therefore, we hypothesized that TQ with these pharmacological effects can reduce CLZ-induced toxicity in isolated cardiomyocytes and mitochondria. Rat left ventricular cardiomyocytes and mitochondria were isolated by collagenase perfusion and differential centrifugation respectively. Then, isolated cardiomyocytes and mitochondria were pretreated with different concentrations of TQ (1, 5, and 10 μmol/l) for 30 min and then followed by exposure to CLZ (50 μmol/l) for 6 h. After 6 h of incubation, using biochemical evaluations and flow cytometric analysis, the parameters of cellular toxicity including cytotoxicity, the level of oxidized/reduced glutathione (GSH/GSSG), malondialdehyde (MDA), reactive oxygen species (ROS) formation, lysosomal membrane integrity, mitochondria membrane potential (ΔΨm) collapse, and mitochondrial toxicity including succinate dehydrogenase (SDH) activity and mitochondrial swelling were analyzed. We observed a significant toxicity in isolated cardiomyocytes and mitochondria after exposure with CLZ which was related to ROS formation, oxidative stress, GSH depletion, lysosomal and mitochondrial damages, and mitochondrial dysfunction and swelling, while TQ pretreatment reverted the above toxic effect of CLZ on isolated cardiomyocytes and mitochondria. Our results indicate that TQ prevents and reverses CLZ-induced cytotoxicity and mitochondrial damages in isolated cardiomyocytes and mitochondria, providing an experimental basis for clinical treatment on CLZ-induced cardiotoxicity.
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