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Kalnytska O, Qvist P, Kunz S, Conrad T, Willnow TE, Schmidt V. SORCS2 activity in pancreatic α-cells safeguards insulin granule formation and release from glucose-stressed β-cells. iScience 2024; 27:108725. [PMID: 38226160 PMCID: PMC10788290 DOI: 10.1016/j.isci.2023.108725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 09/18/2023] [Accepted: 12/11/2023] [Indexed: 01/17/2024] Open
Abstract
Sorting receptor SORCS2 is a stress-response factor protecting neurons from acute insults, such as during epilepsy. SORCS2 is also expressed in the pancreas, yet its action in this tissue remains unknown. Combining metabolic studies in SORCS2-deficient mice with ex vivo functional analyses and single-cell transcriptomics of pancreatic tissues, we identified a role for SORCS2 in protective stress response in pancreatic islets, essential to sustain insulin release. We show that SORCS2 is predominantly expressed in islet alpha cells. Loss of expression coincides with inability of these cells to produce osteopontin, a secreted factor that facilitates insulin release from stressed beta cells. In line with diminished osteopontin levels, beta cells in SORCS2-deficient islets show gene expression patterns indicative of aggravated cell stress, and exhibit defects in insulin granule maturation and a blunted glucose response. These findings corroborate a function for SORCS2 in protective stress response that extends to metabolism.
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Affiliation(s)
- Oleksandra Kalnytska
- Molecular Cardiovascular Research, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany
- Charité – Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Per Qvist
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Séverine Kunz
- Technology Platform for Electron Microscopy, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany
| | - Thomas Conrad
- Genomics Technology Platform, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 10115 Berlin, Germany
| | - Thomas E. Willnow
- Molecular Cardiovascular Research, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany
- Charité – Universitätsmedizin Berlin, 10117 Berlin, Germany
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Vanessa Schmidt
- Molecular Cardiovascular Research, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany
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Kuś J, Saramowicz K, Czerniawska M, Wiese W, Siwecka N, Rozpędek-Kamińska W, Kucharska-Lusina A, Strzelecki D, Majsterek I. Molecular Mechanisms Underlying NMDARs Dysfunction and Their Role in ADHD Pathogenesis. Int J Mol Sci 2023; 24:12983. [PMID: 37629164 PMCID: PMC10454781 DOI: 10.3390/ijms241612983] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 08/27/2023] Open
Abstract
Attention deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders, although the aetiology of ADHD is not yet understood. One proposed theory for developing ADHD is N-methyl-D-aspartate receptors (NMDARs) dysfunction. NMDARs are involved in regulating synaptic plasticity and memory function in the brain. Abnormal expression or polymorphism of some genes associated with ADHD results in NMDAR dysfunction. Correspondingly, NMDAR malfunction in animal models results in ADHD-like symptoms, such as impulsivity and hyperactivity. Currently, there are no drugs for ADHD that specifically target NMDARs. However, NMDAR-stabilizing drugs have shown promise in improving ADHD symptoms with fewer side effects than the currently most widely used psychostimulant in ADHD treatment, methylphenidate. In this review, we outline the molecular and genetic basis of NMDAR malfunction and how it affects the course of ADHD. We also present new therapeutic options related to treating ADHD by targeting NMDAR.
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Affiliation(s)
- Justyna Kuś
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, Mazowiecka 5, 92-215 Lodz, Poland; (J.K.); (K.S.); (M.C.); (W.W.); (N.S.); (W.R.-K.); (A.K.-L.)
| | - Kamil Saramowicz
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, Mazowiecka 5, 92-215 Lodz, Poland; (J.K.); (K.S.); (M.C.); (W.W.); (N.S.); (W.R.-K.); (A.K.-L.)
| | - Maria Czerniawska
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, Mazowiecka 5, 92-215 Lodz, Poland; (J.K.); (K.S.); (M.C.); (W.W.); (N.S.); (W.R.-K.); (A.K.-L.)
| | - Wojciech Wiese
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, Mazowiecka 5, 92-215 Lodz, Poland; (J.K.); (K.S.); (M.C.); (W.W.); (N.S.); (W.R.-K.); (A.K.-L.)
| | - Natalia Siwecka
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, Mazowiecka 5, 92-215 Lodz, Poland; (J.K.); (K.S.); (M.C.); (W.W.); (N.S.); (W.R.-K.); (A.K.-L.)
| | - Wioletta Rozpędek-Kamińska
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, Mazowiecka 5, 92-215 Lodz, Poland; (J.K.); (K.S.); (M.C.); (W.W.); (N.S.); (W.R.-K.); (A.K.-L.)
| | - Aleksandra Kucharska-Lusina
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, Mazowiecka 5, 92-215 Lodz, Poland; (J.K.); (K.S.); (M.C.); (W.W.); (N.S.); (W.R.-K.); (A.K.-L.)
| | - Dominik Strzelecki
- Department of Affective and Psychotic Disorders, Medical University of Lodz, Czechoslowacka 8/10, 92-216 Lodz, Poland;
| | - Ireneusz Majsterek
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, Mazowiecka 5, 92-215 Lodz, Poland; (J.K.); (K.S.); (M.C.); (W.W.); (N.S.); (W.R.-K.); (A.K.-L.)
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Gospodinova KO, Olsen D, Kaas M, Anderson SM, Phillips J, Walker RM, Bermingham ML, Payne AL, Giannopoulos P, Pandya D, Spires-Jones TL, Abbott CM, Porteous DJ, Glerup S, Evans KL. Loss of SORCS2 is Associated with Neuronal DNA Double-Strand Breaks. Cell Mol Neurobiol 2023; 43:237-249. [PMID: 34741697 PMCID: PMC9813074 DOI: 10.1007/s10571-021-01163-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 10/29/2021] [Indexed: 01/09/2023]
Abstract
SORCS2 is one of five proteins that constitute the Vps10p-domain receptor family. Members of this family play important roles in cellular processes linked to neuronal survival, differentiation and function. Genetic and functional studies implicate SORCS2 in cognitive function, as well as in neurodegenerative and psychiatric disorders. DNA damage and DNA repair deficits are linked to ageing and neurodegeneration, and transient neuronal DNA double-strand breaks (DSBs) also occur as a result of neuronal activity. Here, we report a novel role for SORCS2 in DSB formation. We show that SorCS2 loss is associated with elevated DSB levels in the mouse dentate gyrus and that knocking out SORCS2 in a human neuronal cell line increased Topoisomerase IIβ-dependent DSB formation and reduced neuronal viability. Neuronal stimulation had no impact on levels of DNA breaks in vitro, suggesting that the observed differences may not be the result of aberrant neuronal activity in these cells. Our findings are consistent with studies linking the VPS10 receptors and DNA damage to neurodegenerative conditions.
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Affiliation(s)
- Katerina O. Gospodinova
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Ditte Olsen
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Mathias Kaas
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Susan M. Anderson
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Jonathan Phillips
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Rosie M. Walker
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK ,Present Address: University of Edinburgh, Chancellor’s Building, 49, Edinburgh, EH16 4SB UK
| | - Mairead L. Bermingham
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Abigail L. Payne
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Panagiotis Giannopoulos
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Divya Pandya
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Tara L. Spires-Jones
- Centre for Discovery Brain Sciences, UK Dementia Research Institute, University of Edinburgh, Edinburgh, EH8 9XD UK
| | - Catherine M. Abbott
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - David J. Porteous
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Simon Glerup
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Kathryn L. Evans
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
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Salasova A, Monti G, Andersen OM, Nykjaer A. Finding memo: versatile interactions of the VPS10p-Domain receptors in Alzheimer’s disease. Mol Neurodegener 2022; 17:74. [PMID: 36397124 PMCID: PMC9673319 DOI: 10.1186/s13024-022-00576-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Accepted: 10/17/2022] [Indexed: 11/19/2022] Open
Abstract
The family of VPS10p-Domain (D) receptors comprises five members named SorLA, Sortilin, SorCS1, SorCS2 and SorCS3. While their physiological roles remain incompletely resolved, they have been recognized for their signaling engagements and trafficking abilities, navigating a number of molecules between endosome, Golgi compartments, and the cell surface. Strikingly, recent studies connected all the VPS10p-D receptors to Alzheimer’s disease (AD) development. In addition, they have been also associated with diseases comorbid with AD such as diabetes mellitus and major depressive disorder. This systematic review elaborates on genetic, functional, and mechanistic insights into how dysfunction in VPS10p-D receptors may contribute to AD etiology, AD onset diversity, and AD comorbidities. Starting with their functions in controlling cellular trafficking of amyloid precursor protein and the metabolism of the amyloid beta peptide, we present and exemplify how these receptors, despite being structurally similar, regulate various and distinct cellular events involved in AD. This includes a plethora of signaling crosstalks that impact on neuronal survival, neuronal wiring, neuronal polarity, and synaptic plasticity. Signaling activities of the VPS10p-D receptors are especially linked, but not limited to, the regulation of neuronal fitness and apoptosis via their physical interaction with pro- and mature neurotrophins and their receptors. By compiling the functional versatility of VPS10p-D receptors and their interactions with AD-related pathways, we aim to further propel the AD research towards VPS10p-D receptor family, knowledge that may lead to new diagnostic markers and therapeutic strategies for AD patients.
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Kessi M, Duan H, Xiong J, Chen B, He F, Yang L, Ma Y, Bamgbade OA, Peng J, Yin F. Attention-deficit/hyperactive disorder updates. Front Mol Neurosci 2022; 15:925049. [PMID: 36211978 PMCID: PMC9532551 DOI: 10.3389/fnmol.2022.925049] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 08/26/2022] [Indexed: 11/15/2022] Open
Abstract
Background Attention-deficit/hyperactive disorder (ADHD) is a neurodevelopmental disorder that commonly occurs in children with a prevalence ranging from 3.4 to 7.2%. It profoundly affects academic achievement, well-being, and social interactions. As a result, this disorder is of high cost to both individuals and society. Despite the availability of knowledge regarding the mechanisms of ADHD, the pathogenesis is not clear, hence, the existence of many challenges especially in making correct early diagnosis and provision of accurate management. Objectives We aimed to review the pathogenic pathways of ADHD in children. The major focus was to provide an update on the reported etiologies in humans, animal models, modulators, therapies, mechanisms, epigenetic changes, and the interaction between genetic and environmental factors. Methods References for this review were identified through a systematic search in PubMed by using special keywords for all years until January 2022. Results Several genes have been reported to associate with ADHD: DRD1, DRD2, DRD4, DAT1, TPH2, HTR1A, HTR1B, SLC6A4, HTR2A, DBH, NET1, ADRA2A, ADRA2C, CHRNA4, CHRNA7, GAD1, GRM1, GRM5, GRM7, GRM8, TARBP1, ADGRL3, FGF1, MAOA, BDNF, SNAP25, STX1A, ATXN7, and SORCS2. Some of these genes have evidence both from human beings and animal models, while others have evidence in either humans or animal models only. Notably, most of these animal models are knockout and do not generate the genetic alteration of the patients. Besides, some of the gene polymorphisms reported differ according to the ethnic groups. The majority of the available animal models are related to the dopaminergic pathway. Epigenetic changes including SUMOylation, methylation, and acetylation have been reported in genes related to the dopaminergic pathway. Conclusion The dopaminergic pathway remains to be crucial in the pathogenesis of ADHD. It can be affected by environmental factors and other pathways. Nevertheless, it is still unclear how environmental factors relate to all neurotransmitter pathways; thus, more studies are needed. Although several genes have been related to ADHD, there are few animal model studies on the majority of the genes, and they do not generate the genetic alteration of the patients. More animal models and epigenetic studies are required.
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Affiliation(s)
- Miriam Kessi
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Haolin Duan
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Juan Xiong
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Baiyu Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Fang He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Lifen Yang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Yanli Ma
- Department of Neurology, Children’s Hospital Affiliated to Zhengzhou University, Henan Children’s Hospital, Zhengzhou Children’s Hospital, Zhengzhou, China
| | - Olumuyiwa A. Bamgbade
- Department of Anesthesiology and Pharmacology, University of British Columbia, Vancouver, BC, Canada
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
- Hunan Intellectual and Developmental Disabilities Research Center, Changsha, China
- *Correspondence: Fei Yin,
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Fujisawa TX, Nishitani S, Makita K, Yao A, Takiguchi S, Hamamura S, Shimada K, Okazawa H, Matsuzaki H, Tomoda A. Association of Epigenetic Differences Screened in a Few Cases of Monozygotic Twins Discordant for Attention-Deficit Hyperactivity Disorder With Brain Structures. Front Neurosci 2022; 15:799761. [PMID: 35145374 PMCID: PMC8823258 DOI: 10.3389/fnins.2021.799761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 12/16/2021] [Indexed: 11/13/2022] Open
Abstract
The present study examined the relationship between DNA methylation differences and variations in brain structures involved in the development of attention-deficit hyperactivity disorder (ADHD). First, we used monozygotic (MZ) twins discordant (2 pairs of 4 individuals, 2 boys, mean age 12.5 years) for ADHD to identify candidate DNA methylation sites involved in the development of ADHD. Next, we tried to replicate these candidates in a case-control study (ADHD: N = 18, 15 boys, mean age 10.0 years; Controls: N = 62, 40 boys, mean age 13.9 years). Finally, we examined how methylation rates at those sites relate to the degree of local structural alterations where significant differences were observed between cases and controls. As a result, we identified 61 candidate DNA methylation sites involved in ADHD development in two pairs of discordant MZ twins, among which elevated methylation at a site in the sortilin-related Vps10p domain containing receptor 2 (SorCS2) gene was replicated in the case-control study. We also observed that the ADHD group had significantly reduced gray matter volume (GMV) in the precentral and posterior orbital gyri compared to the control group and that this volume reduction was positively associated with SorCS2 methylation. Furthermore, the reduced GMV regions in children with ADHD are involved in language processing and emotional control, while SorCS2 methylation is also negatively associated with emotional behavioral problems in children. These results indicate that SorCS2 methylation might mediate a reduced GMV in the precentral and posterior orbital gyri and therefore influence the pathology of children with ADHD.
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Affiliation(s)
- Takashi X. Fujisawa
- Research Center for Child Mental Development, University of Fukui, Fukui, Japan
- Division of Developmental Higher Brain Functions, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Osaka, Japan
- *Correspondence: Takashi X. Fujisawa,
| | - Shota Nishitani
- Research Center for Child Mental Development, University of Fukui, Fukui, Japan
- Division of Developmental Higher Brain Functions, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Osaka, Japan
| | - Kai Makita
- Research Center for Child Mental Development, University of Fukui, Fukui, Japan
| | - Akiko Yao
- Research Center for Child Mental Development, University of Fukui, Fukui, Japan
- Division of Developmental Higher Brain Functions, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Osaka, Japan
| | - Shinichiro Takiguchi
- Department of Child and Adolescent Psychological Medicine, University of Fukui Hospital, Fukui, Japan
| | - Shoko Hamamura
- Division of Developmental Higher Brain Functions, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Osaka, Japan
- Department of Child and Adolescent Psychological Medicine, University of Fukui Hospital, Fukui, Japan
| | - Koji Shimada
- Research Center for Child Mental Development, University of Fukui, Fukui, Japan
- Division of Developmental Higher Brain Functions, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Osaka, Japan
- Biomedical Imaging Research Center, University of Fukui, Fukui, Japan
| | - Hidehiko Okazawa
- Research Center for Child Mental Development, University of Fukui, Fukui, Japan
- Division of Developmental Higher Brain Functions, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Osaka, Japan
- Biomedical Imaging Research Center, University of Fukui, Fukui, Japan
| | - Hideo Matsuzaki
- Research Center for Child Mental Development, University of Fukui, Fukui, Japan
- Division of Developmental Higher Brain Functions, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Osaka, Japan
- Department of Child and Adolescent Psychological Medicine, University of Fukui Hospital, Fukui, Japan
| | - Akemi Tomoda
- Research Center for Child Mental Development, University of Fukui, Fukui, Japan
- Division of Developmental Higher Brain Functions, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University, and University of Fukui, Osaka, Japan
- Department of Child and Adolescent Psychological Medicine, University of Fukui Hospital, Fukui, Japan
- *Correspondence: Takashi X. Fujisawa,
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Aster HC, Romanos M, Walitza S, Gerlach M, Mühlberger A, Rizzo A, Andreatta M, Hasenauer N, Hartrampf PE, Nerlich K, Reiners C, Lorenz R, Buck AK, Deserno L. Responsivity of the Striatal Dopamine System to Methylphenidate-A Within-Subject I-123-β-CIT-SPECT Study in Male Children and Adolescents With Attention-Deficit/Hyperactivity Disorder. Front Psychiatry 2022; 13:804730. [PMID: 35492708 PMCID: PMC9046584 DOI: 10.3389/fpsyt.2022.804730] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 02/15/2022] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Methylphenidate (MPH) is the first-line pharmacological treatment of attention-deficit/hyperactivity disorder (ADHD). MPH binds to the dopamine (DA) transporter (DAT), which has high density in the striatum. Assessments of the striatal dopamine transporter by single positron emission computed tomography (SPECT) in childhood and adolescent patients are rare but can provide insight on how the effects of MPH affect DAT availability. The aim of our within-subject study was to investigate the effect of MPH on DAT availability and how responsivity to MPH in DAT availability is linked to clinical symptoms and cognitive functioning. METHODS Thirteen adolescent male patients (9-16 years) with a diagnosis of ADHD according to the DSM-IV and long-term stimulant medication (for at least 6 months) with MPH were assessed twice within 7 days using SPECT after application of I-123-β-CIT to examine DAT binding potential (DAT BP). SPECT measures took place in an on- and off-MPH status balanced for order across participants. A virtual reality continuous performance test was performed at each time point. Further clinical symptoms were assessed for baseline off-MPH. RESULTS On-MPH status was associated with a highly significant change (-29.9%) of striatal DAT BP as compared to off-MPH (t = -4.12, p = 0.002). A more pronounced change in striatal DAT BP was associated with higher off-MPH attentional and externalizing symptom ratings (Pearson r = 0.68, p = 0.01). Striatal DAT BP off-MPH, but not on-MPH, was associated with higher symptom ratings (Pearson r = 0.56, p = 0.04). CONCLUSION Our findings corroborate previous reports from mainly adult samples that MPH changes striatal DAT BP availability and suggest higher off-MPH DAT BP, likely reflecting low baseline DA levels, as a marker of symptom severity.
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Affiliation(s)
- Hans-Christoph Aster
- Department of Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, University of Würzburg, Würzburg, Germany.,Department of Neurology, University of Würzburg, Würzburg, Germany
| | - Marcel Romanos
- Department of Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, University of Würzburg, Würzburg, Germany
| | - Susanne Walitza
- Department of Child and Adolescent Psychiatry and Psychotherapy, University Hospital of Psychiatry, University of Zurich, Zurich, Switzerland
| | - Manfred Gerlach
- Department of Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, University of Würzburg, Würzburg, Germany
| | - Andreas Mühlberger
- Department of Psychology, Clinical Psychology and Psychotherapy, University of Regensburg, Regensburg, Germany
| | - Albert Rizzo
- Department of Psychiatry and Behavioral Sciences, University of Southern California (USC) Davis School of Gerontology and USC Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Marta Andreatta
- Clinical Psychology, Erasmus School of Social and Behavioural Sciences, Rotterdam, Netherlands
| | - Natalie Hasenauer
- Department of Nuclear Medicine, University of Würzburg, Würzburg, Germany
| | | | - Kai Nerlich
- Department of Nuclear Medicine, University of Würzburg, Würzburg, Germany
| | - Christoph Reiners
- Department of Nuclear Medicine, University of Würzburg, Würzburg, Germany
| | - Reinhard Lorenz
- Department of Nuclear Medicine, University of Würzburg, Würzburg, Germany
| | - Andreas K Buck
- Department of Nuclear Medicine, University of Würzburg, Würzburg, Germany
| | - Lorenz Deserno
- Department of Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, University of Würzburg, Würzburg, Germany.,Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Department of Psychiatry and Psychotherapy, Technische Universität Dresden, Dresden, Germany
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