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Valderrama-Mantilla AI, Martín-Cuevas C, Gómez-Garrido A, Morente-Montilla C, Crespo-Facorro B, García-Cerro S. Shared Molecular Signature in Alzheimer's Disease and Schizophrenia: A Systematic Review of the Reelin Signaling Pathway. Neurosci Biobehav Rev 2025; 169:106032. [PMID: 39894421 DOI: 10.1016/j.neubiorev.2025.106032] [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: 12/23/2024] [Revised: 01/21/2025] [Accepted: 01/26/2025] [Indexed: 02/04/2025]
Abstract
The Reelin signaling pathway, particularly the RELN-APOER2-DAB1 complex, has emerged as a key contributor to the neuropathology of Alzheimer's disease (AD) and Schizophrenia (SZ). Despite being distinct clinical conditions, these disorders exhibit similar patterns of cognitive decline, including early disruptions in synaptic function and memory impairments. Notably, individuals with SZ have a 2-4 fold increased risk of developing AD or other dementias, highlighting potential shared molecular mechanisms, and positioning Reelin as a pivotal link between them. This systematic review explores the role of Reelin and its signaling components across these disorders. In AD, Reelin disruption correlates with hallmark features such as Tau hyperphosphorylation, amyloid-beta accumulation, and cognitive deficits. In SZ, alterations in Reelin signaling, including epigenetic modifications affecting RELN expression, are linked to disruptions in neuronal development and synaptic plasticity, particularly in the parietal and prefrontal cortices. Additionally, genomic studies reveal specific RELN variants and allelic imbalances that may influence disease severity and treatment response in SZ, suggesting RELN's role as a potential biomarker for therapeutic outcomes. Region-specific Reelin alterations in both AD and SZ suggest differing impacts yet underscore a potential common molecular origin. Our findings highlight the Reelin pathway as a molecular convergence point, warranting further investigation as a therapeutic and diagnostic target for AD, SZ, and potentially other neuropsychiatric disorders. The interplay between genetic and epigenetic regulation of RELN may provide novel insights into neurodegeneration, with implications for personalized intervention strategies in AD and SZ.
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Affiliation(s)
| | - Celia Martín-Cuevas
- Instituto de Biomedicina de Sevilla (IBiS)/University Hospital Virgen del Rocío/CSIC/University of Sevilla, Manuel Siurot AV, 41013, Seville, Spain; Spanish Network for Research in Mental Health (CIBERSAM, ISCIII), Monforte de Lemos AV, 3-5, 28029, Madrid, Spain.
| | - Ana Gómez-Garrido
- Instituto de Biomedicina de Sevilla (IBiS)/University Hospital Virgen del Rocío/CSIC/University of Sevilla, Manuel Siurot AV, 41013, Seville, Spain; Spanish Network for Research in Mental Health (CIBERSAM, ISCIII), Monforte de Lemos AV, 3-5, 28029, Madrid, Spain.
| | - Cristina Morente-Montilla
- Instituto de Biomedicina de Sevilla (IBiS)/University Hospital Virgen del Rocío/CSIC/University of Sevilla, Manuel Siurot AV, 41013, Seville, Spain.
| | - Benedicto Crespo-Facorro
- Instituto de Biomedicina de Sevilla (IBiS)/University Hospital Virgen del Rocío/CSIC/University of Sevilla, Manuel Siurot AV, 41013, Seville, Spain; Spanish Network for Research in Mental Health (CIBERSAM, ISCIII), Monforte de Lemos AV, 3-5, 28029, Madrid, Spain; Department of Psychiatry, School of Medicine, University of Seville, Manuel Siurot AV, 41013, Seville, Spain.
| | - Susana García-Cerro
- Instituto de Biomedicina de Sevilla (IBiS)/University Hospital Virgen del Rocío/CSIC/University of Sevilla, Manuel Siurot AV, 41013, Seville, Spain; Spanish Network for Research in Mental Health (CIBERSAM, ISCIII), Monforte de Lemos AV, 3-5, 28029, Madrid, Spain.
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Zhang L, Chen Y, Hong Y, Zhang J, Jiang W, Li Q, Li X, Zhou Y. "Aging Amplifies Challenges": A Descriptive Phenomenological Exploration of the Lived Experiences and Needs of Elderly Individuals With Schizophrenia. Nurs Health Sci 2024; 26:e13168. [PMID: 39385475 DOI: 10.1111/nhs.13168] [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: 07/25/2024] [Revised: 09/24/2024] [Accepted: 09/26/2024] [Indexed: 10/12/2024]
Abstract
Older adults diagnosed with schizophrenia face unique public health challenges, with specific treatment needs, complex care demands, accelerated aging, and increased susceptibility to health issues. This phenomenological study explored the existential realities and needs of older adults diagnosed with schizophrenia. Fifteen participants, with a mean age of 69.47 (SD ± 9.47) years, ranging from 62 to 79 years old and hailing from rural regions, participated in the study. Four main themes and eight sub-themes emerge: compounding the burden (challenges in symptom management, comorbidities); the abyss of a life filled with emptiness (loss of mental pillars, living in agony); living on the margins of society (the vicious cycle of social and self-isolation, unattainable social welfare); and glimmer of light in the darkness (support systems, self-adjustment). The study calls for healthcare professionals to improve follow-up care efficiency, strengthen engagement, understand patients' living conditions and needs, enforce existing welfare policies for older mentally ill patients, and enhance their mental health and quality of life.
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Affiliation(s)
- Linghui Zhang
- Department of Nursing, Harbin Medical University, Harbin, Heilongjiang, China
| | - Yubin Chen
- Department of Nursing, Harbin Medical University, Harbin, Heilongjiang, China
| | - Yu Hong
- Department of Nursing, Harbin Medical University, Harbin, Heilongjiang, China
| | - Jiayuan Zhang
- Department of Nursing, Harbin Medical University, Harbin, Heilongjiang, China
| | - Wenlong Jiang
- Department of Psychiatry, Daqing Third People's Hospital, Daqing, Heilongjiang, China
| | - Qi Li
- Department of Nursing, Harbin Medical University, Harbin, Heilongjiang, China
| | - Xiaoyan Li
- Department of Medicine, Lishui University, Lishui, Zhejiang, China
| | - Yuqiu Zhou
- Department of Nursing, Huzhou University, Huzhou, Zhejiang, China
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Shirai T, Okazaki S, Tanifuji T, Numata S, Nakayama T, Yoshida T, Mouri K, Otsuka I, Hiroi N, Hishimoto A. Meta-analyses of epigenetic age acceleration and GrimAge components of schizophrenia or first-episode psychosis. SCHIZOPHRENIA (HEIDELBERG, GERMANY) 2024; 10:108. [PMID: 39548083 PMCID: PMC11568310 DOI: 10.1038/s41537-024-00531-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2024] [Accepted: 10/31/2024] [Indexed: 11/17/2024]
Abstract
Schizophrenia is a common chronic psychiatric disorder that causes age-related dysfunction. The life expectancy in patients with schizophrenia is ≥10 years shorter than that in the general population because of the higher risk of other diseases, such as cardiovascular diseases. Aging studies based on DNA methylation status have received considerable attention. Several epigenetic age accelerations and predicted values of aging-related proteins (GrimAge and GrimAge2 components) have been analyzed in multiple diseases. However, no studies have investigated up to GrimAge and GrimAge2 components between patients with schizophrenia and controls. Therefore, we aimed to conduct multiple regression analyses to investigate the association between schizophrenia and epigenetic age accelerations and GrimAge and GrimAge2 components in seven cohorts. Furthermore, we included patients with first-episode psychosis whose illness duration was often shorter than schizophrenia in our analysis. We integrated these results with meta-analyses, noting the acceleration of GrimAge, GrimAge2, and DunedinPACE, and increase in adrenomedullin, beta-2 microglobulin, cystatin C, and plasminogen activation inhibitor-1 levels, in patients with schizophrenia or first-episode psychosis. These results corroborated the finding that patients with schizophrenia had an increased risk of diabetes, cardiovascular disease, and cognitive dysfunction from a biological perspective. Patients with schizophrenia and first-episode psychosis showed differences in the results when compared with controls. Such analyses may lead to the development of novel therapeutic targets to patients with schizophrenia or relevant diseases from the perspective of aging in the future.
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Affiliation(s)
- Toshiyuki Shirai
- Department of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Satoshi Okazaki
- Department of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan.
| | - Takaki Tanifuji
- Department of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan
- Department of Pharmacology, UT Health San Antonio, San Antonio, TX, USA
| | - Shusuke Numata
- Department of Psychiatry, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Tomohiko Nakayama
- Department of Psychiatry, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Tomohiro Yoshida
- Department of Psychiatry, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Kentaro Mouri
- Department of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Ikuo Otsuka
- Department of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Noboru Hiroi
- Department of Pharmacology, UT Health San Antonio, San Antonio, TX, USA
| | - Akitoyo Hishimoto
- Department of Psychiatry, Kobe University Graduate School of Medicine, Kobe, Japan
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Fan L, Zhang Z, Ma X, Liang L, Yuan L, Ouyang L, Wang Y, Li Z, Chen X, He Y, Palaniyappan L. Brain Age Gap as a Predictor of Early Treatment Response and Functional Outcomes in First-Episode Schizophrenia: A Longitudinal Study: L'écart d'âge cérébral comme prédicteur de la réponse en début de traitement et des résultats fonctionnels dans un premier épisode de schizophrénie : une étude longitudinale. CANADIAN JOURNAL OF PSYCHIATRY. REVUE CANADIENNE DE PSYCHIATRIE 2024:7067437241293981. [PMID: 39523517 PMCID: PMC11562934 DOI: 10.1177/07067437241293981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2024]
Abstract
OBJECTIVES Accelerated brain aging, i.e., the age-related structural changes in the brain appearing earlier than expected from one's chronological age, is a feature that is now well established in schizophrenia. Often interpreted as a feature of a progressive pathophysiological process that typifies schizophrenia, its prognostic relevance is still unclear. We investigate its role in response to antipsychotic treatment in first-episode schizophrenia. METHODS We recruited 49 drug-naive patients with schizophrenia who were then treated with risperidone at a standard dose range of 2-6 mg/day. We followed them up for 3 months to categorize their response status. We acquired T1-weighted anatomical images and used the XGboost method to evaluate individual brain age. The brain age gap (BAG) is the difference between the predicted brain age and chronological age. RESULTS Patients with FES had more pronounced BAG compared to healthy subjects, and this difference was primarily driven by those who did not respond adequately after 12 weeks of treatment. BAG did not worsen significantly over the 12-week period, indicating a lack of prominent brain-ageing effect induced by the early antipsychotic exposure per se. However, highly symptomatic patients had a more prominent increase in BAG, while patients with higher BAG when initiating treatment later showed lower gains in global functioning upon treatment, highlighting the prognostic value of BAG measures in FES. CONCLUSIONS Accelerated brain aging is a feature of first-episode schizophrenia that is more likely to be seen among those who will not respond adequately to first-line antipsychotic use. Given that early poor response indicates later treatment resistance, measuring BAG using structural MRI in the first 12 weeks of treatment initiation may provide useful prognostic information when considering second-line treatments in schizophrenia.
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Affiliation(s)
- Lejia Fan
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, QC, Canada
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Zhenmei Zhang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Xiaoqian Ma
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Liangbing Liang
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Liu Yuan
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Lijun Ouyang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Yujue Wang
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Zongchang Li
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Xiaogang Chen
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Ying He
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, and National Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Lena Palaniyappan
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, QC, Canada
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
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Abstract
PURPOSE OF REVIEW Sleep disorders encompass a wide range of conditions with substantial individual variability. Epigenetics, the study of heritable changes beyond DNA sequence, offers a promising avenue for personalized medicine in this field. RECENT FINDINGS There is great potential of epigenetic markers for sleep disorder diagnosis and the development of epigenetic drugs for targeted treatment. Epigenetic age acceleration, a marker of biological aging, is linked to sleep disorders and comorbidities. Very importantly, this acceleration may be reversible with effective treatment. SUMMARY While the underlying mechanisms and assessment of clinical utility require further investigation, the potential of epigenetics in sleep medicine is recognized. Future research focused on closing knowledge gaps and clinical validation is crucial to translate these findings into practical applications, paving the way for more effective and personalized management of sleep disorders.
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Affiliation(s)
- Rene Cortese
- Departments of Pediatrics and Obstetrics, Gynecology and Wiomen’s Health. School of Medicine. University of Missouri. Columbia, MO, 65211, USA
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Waddington JL, Wang X, Zhen X. 'Whole-Body' Perspectives of Schizophrenia and Related Psychotic Illness: miRNA-143 as an Exemplary Molecule Implicated across Multi-System Dysfunctions. Biomolecules 2024; 14:1185. [PMID: 39334950 PMCID: PMC11430658 DOI: 10.3390/biom14091185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2024] [Revised: 09/17/2024] [Accepted: 09/18/2024] [Indexed: 09/30/2024] Open
Abstract
A wide array of biological abnormalities in psychotic illness appear to reflect non-cerebral involvement. This review first outlines the evidence for such a whole-body concept of schizophrenia pathobiology, focusing particularly on cardiovascular disease, metabolic syndrome and diabetes, immunity and inflammation, cancer, and the gut-brain axis. It then considers the roles of miRNAs in general and of miRNA-143 in particular as they relate to the epidemiology, pathobiology, and treatment of schizophrenia. This is followed by notable evidence that miRNA-143 is also implicated in each of these domains of cardiovascular disease, metabolic syndrome and diabetes, immunity and inflammation, cancer, and the gut-brain axis. Thus, miRNA-143 is an exemplar of what may be a class of molecules that play a role across the multiple domains of bodily dysfunction that appear to characterize a whole-body perspective of illness in schizophrenia. Importantly, the existence of such an exemplary molecule across these multiple domains implies a coordinated rather than stochastic basis. One candidate process would be a pleiotropic effect of genetic risk for schizophrenia across the whole body.
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Affiliation(s)
- John L. Waddington
- School of Pharmacy and Biomolecular Sciences, RCSI University of Medicine and Health Sciences, D02 YN77 Dublin, Ireland
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psychiatric-Disorders, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China; (X.W.); (X.Z.)
| | - Xiaoyu Wang
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psychiatric-Disorders, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China; (X.W.); (X.Z.)
| | - Xuechu Zhen
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psychiatric-Disorders, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China; (X.W.); (X.Z.)
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Genkel V, Domozhirova E, Malinina E. Multimorbidity in Severe Mental Illness as Part of the Neurodevelopmental Continuum: Physical Health-Related Endophenotypes of Schizophrenia-A Narrative Review. Brain Sci 2024; 14:725. [PMID: 39061465 PMCID: PMC11274495 DOI: 10.3390/brainsci14070725] [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: 07/02/2024] [Revised: 07/14/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024] Open
Abstract
BACKGROUND The majority of deaths in patients with schizophrenia and other severe mental illnesses (SMIs) are caused by natural causes, such as cardiovascular diseases (CVDs). The increased risk of CVD and other somatic diseases in SMIs cannot be fully explained by the contribution of traditional risk factors, behavioral risk factors, patients' lifestyle peculiarities, and the influence of antipsychotics. The present review has the following main objectives: (1) to aggregate evidence that neurodevelopmental disorders are the basis of SMIs; (2) to provide a review of studies that have addressed the shared genetic architecture of SMI and cardiovascular disease; and (3) to propose and substantiate the consideration of somatic diseases as independent endophenotypes of SMIs, which will make it possible to place the research of somatic diseases in SMIs within the framework of the concepts of the "neurodevelopmental continuum and gradient" and "endophenotype". METHODS A comprehensive literature search was performed on 1 July 2024. The search was performed using PubMed and Google Scholar databases up to June 2024. RESULTS The current literature reveals considerable overlap between the genetic susceptibility loci for SMIs and CVDs. We propose that somatic diseases observed in SMIs that have a shared genetic architecture with SMIs can be considered distinct physical health-related endophenotypes. CONCLUSIONS In this narrative review, the results of recent studies of CVDs in SMIs are summarized. Reframing schizophrenia as a multisystem disease should contribute to the activation of new research on somatic diseases in SMIs.
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Affiliation(s)
- Vadim Genkel
- Department of Internal Medicine, South-Ural State Medical University, Chelyabinsk 454092, Russia
| | - Elena Domozhirova
- Department of Psychiatry, South-Ural State Medical University, Chelyabinsk 454092, Russia; (E.D.); (E.M.)
| | - Elena Malinina
- Department of Psychiatry, South-Ural State Medical University, Chelyabinsk 454092, Russia; (E.D.); (E.M.)
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Baran B, Lee EE. Age-Related Changes in Sleep and Its Implications for Cognitive Decline in Aging Persons With Schizophrenia: A Critical Review. Schizophr Bull 2024:sbae059. [PMID: 38713085 DOI: 10.1093/schbul/sbae059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
BACKGROUND AND HYPOTHESIS Cognitive impairment is a core feature of schizophrenia that worsens with aging and interferes with quality of life. Recent work identifies sleep as an actionable target to alleviate cognitive deficits. Cardinal non-rapid eye movement (NREM) sleep oscillations such as sleep spindles and slow oscillations are critical for cognition. People living with schizophrenia (PLWS) and their first-degree relatives have a specific reduction in sleep spindles and an abnormality in their temporal coordination with slow oscillations that predict impaired memory consolidation. While NREM oscillatory activity is reduced in typical aging, it is not known how further disruption in these oscillations contributes to cognitive decline in older PLWS. Another understudied risk factor for cognitive deficits among older PLWS is obstructive sleep apnea (OSA) which may contribute to cognitive decline. STUDY DESIGN We conducted a narrative review to examine the published literature on aging, OSA, and NREM sleep oscillations in PLWS. STUDY RESULTS Spindles are propagated via thalamocortical feedback loops, and this circuitry shows abnormal hyperconnectivity in schizophrenia as revealed by structural and functional MRI studies. While the risk and severity of OSA increase with age, older PLWS are particularly vulnerable to OSA-related cognitive deficits because OSA is often underdiagnosed and undertreated, and OSA adds further damage to the circuitry that generates NREM sleep oscillations. CONCLUSIONS We highlight the critical need to study NREM sleep in older PWLS and propose that identifying and treating OSA in older PLWS will provide an avenue to potentially mitigate and prevent cognitive decline.
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Affiliation(s)
- Bengi Baran
- Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA, USA
- Department of Psychiatry, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
- Iowa Neuroscience Institute, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Ellen E Lee
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
- Desert-Pacific Mental Illness Research Education and Clinical Center, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
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Mamah D, Chen S, Shimony JS, Harms MP. Tract-based analyses of white matter in schizophrenia, bipolar disorder, aging, and dementia using high spatial and directional resolution diffusion imaging: a pilot study. Front Psychiatry 2024; 15:1240502. [PMID: 38362028 PMCID: PMC10867155 DOI: 10.3389/fpsyt.2024.1240502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 01/15/2024] [Indexed: 02/17/2024] Open
Abstract
Introduction Structural brain connectivity abnormalities have been associated with several psychiatric disorders. Schizophrenia (SCZ) is a chronic disabling disorder associated with accelerated aging and increased risk of dementia, though brain findings in the disorder have rarely been directly compared to those that occur with aging. Methods We used an automated approach to reconstruct key white matter tracts and assessed tract integrity in five participant groups. We acquired one-hour-long high-directional diffusion MRI data from young control (CON, n =28), bipolar disorder (BPD, n =21), and SCZ (n =22) participants aged 18-30, and healthy elderly (ELD, n =15) and dementia (DEM, n =9) participants. Volume, fractional (FA), radial diffusivity (RD) and axial diffusivity (AD) of seven key white matter tracts (anterior thalamic radiation, ATR; dorsal and ventral cingulum bundle, CBD and CBV; corticospinal tract, CST; and the three superior longitudinal fasciculi: SLF-1, SLF-2 and SLF-3) were analyzed with TRACULA. Group comparisons in tract metrics were performed using multivariate and univariate analyses. Clinical relationships of tract metrics with recent and chronic symptoms were assessed in SCZ and BPD participants. Results A MANOVA showed group differences in FA (λ=0.5; p=0.0002) and RD (λ=0.35; p<0.0001) across the seven tracts, but no significant differences in tract AD and volume. Post-hoc analyses indicated lower tract FA and higher RD in ELD and DEM groups compared to CON, BPD and SCZ groups. Lower FA and higher RD in SCZ compared to CON did not meet statistical significance. In SCZ participants, a significant negative correlation was found between chronic psychosis severity and FA in the SLF-1 (r= -0.45; p=0.035), SLF-2 (r= -0.49; p=0.02) and SLF-3 (r= -0.44; p=0.042). Discussion Our results indicate impaired white matter tract integrity in elderly populations consistent with myelin damage. Impaired tract integrity in SCZ is most prominent in patients with advanced illness.
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Affiliation(s)
- Daniel Mamah
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States
| | - ShingShiun Chen
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States
| | - Joshua S. Shimony
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Michael P. Harms
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, United States
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