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Sarnyai Z, Ben-Shachar D. Schizophrenia, a disease of impaired dynamic metabolic flexibility: A new mechanistic framework. Psychiatry Res 2024; 342:116220. [PMID: 39369460 DOI: 10.1016/j.psychres.2024.116220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 09/21/2024] [Accepted: 09/30/2024] [Indexed: 10/08/2024]
Abstract
Schizophrenia is a chronic, neurodevelopmental disorder with unknown aetiology and pathophysiology that emphasises the role of neurotransmitter imbalance and abnormalities in synaptic plasticity. The currently used pharmacological approach, the antipsychotic drugs, which have limited efficacy and an array of side-effects, have been developed based on the neurotransmitter hypothesis. Recent research has uncovered systemic and brain abnormalities in glucose and energy metabolism, focusing on altered glycolysis and mitochondrial oxidative phosphorylation. These findings call for a re-conceptualisation of schizophrenia pathophysiology as a progressing bioenergetics failure. In this review, we provide an overview of the fundamentals of brain bioenergetics and the changes identified in schizophrenia. We then propose a new explanatory framework positing that schizophrenia is a disease of impaired dynamic metabolic flexibility, which also reconciles findings of abnormal glucose and energy metabolism in the periphery and in the brain along the course of the disease. This evidence-based framework and testable hypothesis has the potential to transform the way we conceptualise this debilitating condition and to develop novel treatment approaches.
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Affiliation(s)
- Zoltán Sarnyai
- Laboratory of Psychobiology, Department of Neuroscience, The Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Department of Psychiatry, Rambam Health Campus, Haifa, Israel; Laboratory of Psychiatric Neuroscience, Australian Institute of Tropical Health and Medicine, James Cook University, Townsville, QLD, Australia.
| | - Dorit Ben-Shachar
- Laboratory of Psychobiology, Department of Neuroscience, The Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Department of Psychiatry, Rambam Health Campus, Haifa, Israel.
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Sahay S, Pulvender P, Rami Reddy MVSR, McCullumsmith RE, O’Donovan SM. Metabolic Insights into Neuropsychiatric Illnesses and Ketogenic Therapies: A Transcriptomic View. Int J Mol Sci 2024; 25:8266. [PMID: 39125835 PMCID: PMC11312282 DOI: 10.3390/ijms25158266] [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: 05/31/2024] [Revised: 07/21/2024] [Accepted: 07/26/2024] [Indexed: 08/12/2024] Open
Abstract
The disruption of brain energy metabolism, leading to alterations in synaptic signaling, neural circuitry, and neuroplasticity, has been implicated in severe mental illnesses such as schizophrenia, bipolar disorder, and major depressive disorder. The therapeutic potential of ketogenic interventions in these disorders suggests a link between metabolic disturbances and disease pathology; however, the precise mechanisms underlying these metabolic disturbances, and the therapeutic effects of metabolic ketogenic therapy, remain poorly understood. In this study, we conducted an in silico analysis of transcriptomic data to investigate perturbations in metabolic pathways in the brain across severe mental illnesses via gene expression profiling. We also examined dysregulation of the same pathways in rodent or cell culture models of ketosis, comparing these expression profiles to those observed in the disease states. Our analysis revealed significant perturbations across all metabolic pathways, with the greatest perturbations in glycolysis, the tricarboxylic acid (TCA) cycle, and the electron transport chain (ETC) across all three disorders. Additionally, we observed some discordant gene expression patterns between disease states and ketogenic intervention studies, suggesting a potential role for ketone bodies in modulating pathogenic metabolic changes. Our findings highlight the importance of understanding metabolic dysregulation in severe mental illnesses and the potential therapeutic benefits of ketogenic interventions in restoring metabolic homeostasis. This study provides insights into the complex relationship between metabolism and neuropsychiatric disorders and lays the foundation for further experimental investigations aimed at appreciating the implications of the present transcriptomic findings as well as developing targeted therapeutic strategies.
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Affiliation(s)
- Smita Sahay
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
| | - Priyanka Pulvender
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
| | | | - Robert E. McCullumsmith
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
- Department of Psychiatry, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
- Neuroscience Institute, ProMedica, Toledo, OH 43614, USA
| | - Sinead M. O’Donovan
- Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
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Yalcinbas EA, Ajanaku B, Nelson ED, Garcia-Flores R, Eagles NJ, Montgomery KD, Stolz JM, Wu J, Divecha HR, Chandra A, Bharadwaj RA, Bach S, Rajpurohit A, Tao R, Pertea G, Shin JH, Kleinman JE, Hyde TM, Weinberger DR, Huuki-Myers LA, Collado-Torres L, Maynard KR. Transcriptomic analysis of the human habenula in schizophrenia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.26.582081. [PMID: 38463979 PMCID: PMC10925152 DOI: 10.1101/2024.02.26.582081] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Pathophysiology of many neuropsychiatric disorders, including schizophrenia (SCZD), is linked to habenula (Hb) function. While pharmacotherapies and deep brain stimulation targeting the Hb are emerging as promising therapeutic treatments, little is known about the cell type-specific transcriptomic organization of the human Hb or how it is altered in SCZD. Here we define the molecular neuroanatomy of the human Hb and identify transcriptomic changes in individuals with SCZD compared to neurotypical controls. Utilizing Hb-enriched postmortem human brain tissue, we performed single nucleus RNA-sequencing (snRNA-seq; n=7 neurotypical donors) and identified 17 molecularly defined Hb cell types across 16,437 nuclei, including 3 medial and 7 lateral Hb populations, several of which were conserved between rodents and humans. Single molecule fluorescent in situ hybridization (smFISH; n=3 neurotypical donors) validated snRNA-seq Hb cell types and mapped their spatial locations. Bulk RNA-sequencing and cell type deconvolution in Hb-enriched tissue from 35 individuals with SCZD and 33 neurotypical controls yielded 45 SCZD-associated differentially expressed genes (DEGs, FDR < 0.05), with 32 (71%) unique to Hb-enriched tissue. eQTL analysis identified 717 independent SNP-gene pairs (FDR < 0.05), where either the SNP is a SCZD risk variant (16 pairs) or the gene is a SCZD DEG (7 pairs). eQTL and SCZD risk colocalization analysis identified 16 colocalized genes. These results identify topographically organized cell types with distinct molecular signatures in the human Hb and demonstrate unique genetic changes associated with SCZD, thereby providing novel molecular insights into the role of Hb in neuropsychiatric disorders. One Sentence Summary Transcriptomic analysis of the human habenula and identification of molecular changes associated with schizophrenia risk and illness state.
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Biswal SR, Kumar A, Muthuswamy S, Kumar S. Genetic components of microdeletion syndromes and their role in determining schizophrenia traits. Mol Biol Rep 2024; 51:804. [PMID: 39001960 DOI: 10.1007/s11033-024-09731-y] [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: 04/27/2024] [Accepted: 06/17/2024] [Indexed: 07/15/2024]
Abstract
Schizophrenia is a neuropsychiatric disorder characterized by various symptoms such as hallucinations, delusions, and disordered thinking. The etiology of this disease is unknown; however, it has been linked to many microdeletion syndromes that are likely to contribute to the pathology of schizophrenia. In this review we have comprehensively analyzed the role of various microdeletion syndromes, like 3q29, 15q13.3, and 22q11.2, which are known to be involved with schizophrenia. A variety of factors lead to schizophrenia phenotypes, but copy number variants that disrupt gene regulation and impair brain function and cognition are one of the causes that have been identified. Multiple case studies have shown that loss of one or more genes in the microdeletion regions lead to brain activity defects. In this article, we present a coherent paradigm that connects copy number variations (CNVs) to numerous neurological and behavioral abnormalities associated with schizophrenia. It would be helpful in understanding the different aspects of the microdeletions and how they contribute in the pathophysiology of schizophrenia.
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Affiliation(s)
- Smruti Rekha Biswal
- Department of Life Science, National Institute of Technology (NIT), Rourkela, Odisha, 769008, India
| | - Ajay Kumar
- Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005, India
| | - Srinivasan Muthuswamy
- Department of Life Science, National Institute of Technology (NIT), Rourkela, Odisha, 769008, India.
| | - Santosh Kumar
- Department of Life Science, National Institute of Technology (NIT), Rourkela, Odisha, 769008, India.
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Fehsel K, Bouvier ML, Capobianco L, Lunetti P, Klein B, Oldiges M, Majora M, Löffler S. Neuroreceptor Inhibition by Clozapine Triggers Mitohormesis and Metabolic Reprogramming in Human Blood Cells. Cells 2024; 13:762. [PMID: 38727298 PMCID: PMC11083702 DOI: 10.3390/cells13090762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 04/26/2024] [Indexed: 05/13/2024] Open
Abstract
The antipsychotic drug clozapine demonstrates superior efficacy in treatment-resistant schizophrenia, but its intracellular mode of action is not completely understood. Here, we analysed the effects of clozapine (2.5-20 µM) on metabolic fluxes, cell respiration, and intracellular ATP in human HL60 cells. Some results were confirmed in leukocytes of clozapine-treated patients. Neuroreceptor inhibition under clozapine reduced Akt activation with decreased glucose uptake, thereby inducing ER stress and the unfolded protein response (UPR). Metabolic profiling by liquid-chromatography/mass-spectrometry revealed downregulation of glycolysis and the pentose phosphate pathway, thereby saving glucose to keep the electron transport chain working. Mitochondrial respiration was dampened by upregulation of the F0F1-ATPase inhibitory factor 1 (IF1) leading to 30-40% lower oxygen consumption in HL60 cells. Blocking IF1 expression by cotreatment with epigallocatechin-3-gallate (EGCG) increased apoptosis of HL60 cells. Upregulation of the mitochondrial citrate carrier shifted excess citrate to the cytosol for use in lipogenesis and for storage as triacylglycerol in lipid droplets (LDs). Accordingly, clozapine-treated HL60 cells and leukocytes from clozapine-treated patients contain more LDs than untreated cells. Since mitochondrial disturbances are described in the pathophysiology of schizophrenia, clozapine-induced mitohormesis is an excellent way to escape energy deficits and improve cell survival.
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Affiliation(s)
- Karin Fehsel
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine-University, Bergische Landstrasse 2, 40629 Duesseldorf, Germany;
| | - Marie-Luise Bouvier
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine-University, Bergische Landstrasse 2, 40629 Duesseldorf, Germany;
| | - Loredana Capobianco
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (L.C.); (P.L.)
| | - Paola Lunetti
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (L.C.); (P.L.)
| | - Bianca Klein
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, Leo-Brandt-Straße, 52428 Jülich, Germany; (B.K.); (M.O.)
| | - Marko Oldiges
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich, Leo-Brandt-Straße, 52428 Jülich, Germany; (B.K.); (M.O.)
| | - Marc Majora
- Leibniz Research Institute for Environmental Medicine (IUF), Auf’m Hennekamp 50, 40225 Düsseldorf, Germany;
| | - Stefan Löffler
- Clinic for Psychiatry, Psychotherapy and Psychosomatics, Sana Klinikum Offenbach, Teaching Hospital of Goethe University, Starkenburgring 66, 63069 Offenbach, Germany;
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Genovese AC, Butler MG. Behavioral and Psychiatric Disorders in Syndromic Autism. Brain Sci 2024; 14:343. [PMID: 38671997 PMCID: PMC11048128 DOI: 10.3390/brainsci14040343] [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: 02/23/2024] [Revised: 03/25/2024] [Accepted: 03/28/2024] [Indexed: 04/28/2024] Open
Abstract
Syndromic autism refers to autism spectrum disorder diagnosed in the context of a known genetic syndrome. The specific manifestations of any one of these syndromic autisms are related to a clinically defined genetic syndrome that can be traced to certain genes and variants, genetic deletions, or duplications at the chromosome level. The genetic mutations or defects in single genes associated with these genetic disorders result in a significant elevation of risk for developing autism relative to the general population and are related to recurrence with inheritance patterns. Additionally, these syndromes are associated with typical behavioral characteristics or phenotypes as well as an increased risk for specific behavioral or psychiatric disorders and clinical findings. Knowledge of these associations helps guide clinicians in identifying potentially treatable conditions that can help to improve the lives of affected patients and their families.
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Affiliation(s)
- Ann C. Genovese
- Department of Psychiatry and Behavioral Sciences, University of Kansas Medical Center, Kansas City, KS 66160, USA;
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