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Mehanna R, Jankovic J. Systemic Symptoms in Huntington's Disease: A Comprehensive Review. Mov Disord Clin Pract 2024; 11:453-464. [PMID: 38529740 PMCID: PMC11078495 DOI: 10.1002/mdc3.14029] [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: 12/02/2023] [Revised: 02/26/2024] [Accepted: 03/12/2024] [Indexed: 03/27/2024] Open
Abstract
BACKGROUND Although Huntington's disease (HD) is usually thought of as a triad of motor, cognitive, and psychiatric symptoms, there is growing appreciation of HD as a systemic illness affecting the entire body. OBJECTIVES This review aims to draw attention to these systemic non-motor symptoms in HD. METHODS We identified relevant studies published in English by searching MEDLINE (from 1966 to September 2023), using the following subject headings: Huntington disease, autonomic, systemic, cardiovascular, respiratory, gastrointestinal, urinary, sexual and cutaneous, and additional specific symptoms. RESULTS Data from 123 articles were critically reviewed with focus on systemic features associated with HD, such as cardiovascular, respiratory, gastrointestinal, urinary, sexual and sweating. CONCLUSION This systematic review draws attention to a variety of systemic and autonomic co-morbidities in patients with HD. Not all of them correlate with the severity of the primary HD symptoms or CAG repeats. More research is needed to better understand the pathophysiology and treatment of systemic and autonomic dysfunction in HD.
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Affiliation(s)
- Raja Mehanna
- Department of Neurology, University of Texas Health Science Center at Houston, McGovern Medical School, Houston, TX, USA
| | - Joseph Jankovic
- Parkinson's Disease Center and Movement Disorders Clinic, Department of Neurology, Baylor College of Medicine, Houston, TX, USA
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2
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Dickson E, Dwijesha AS, Andersson N, Lundh S, Björkqvist M, Petersén Å, Soylu-Kucharz R. Microarray profiling of hypothalamic gene expression changes in Huntington’s disease mouse models. Front Neurosci 2022; 16:1027269. [DOI: 10.3389/fnins.2022.1027269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022] Open
Abstract
Structural changes and neuropathology in the hypothalamus have been suggested to contribute to the non-motor manifestations of Huntington’s disease (HD), a neurodegenerative disorder caused by an expanded cytosine-adenine-guanine (CAG) repeat in the huntingtin (HTT) gene. In this study, we investigated whether hypothalamic HTT expression causes transcriptional changes. Hypothalamic RNA was isolated from two different HD mouse models and their littermate controls; BACHD mice with ubiquitous expression of full-length mutant HTT (mHTT) and wild-type mice with targeted hypothalamic overexpression of either wild-type HTT (wtHTT) or mHTT fragments. The mHTT and wtHTT groups showed the highest number of differentially expressed genes compared to the BACHD mouse model. Gene Set Enrichment Analysis (GSEA) with leading-edge analysis showed that suppressed sterol- and cholesterol metabolism were shared between hypothalamic wtHTT and mHTT overexpression. Most distinctive for mHTT overexpression was the suppression of neuroendocrine networks, in which qRT-PCR validation confirmed significant downregulation of neuropeptides with roles in feeding behavior; hypocretin neuropeptide precursor (Hcrt), tachykinin receptor 3 (Tacr3), cocaine and amphetamine-regulated transcript (Cart) and catecholamine-related biological processes; dopa decarboxylase (Ddc), histidine decarboxylase (Hdc), tyrosine hydroxylase (Th), and vasoactive intestinal peptide (Vip). In BACHD mice, few hypothalamic genes were differentially expressed compared to age-matched WT controls. However, GSEA indicated an enrichment of inflammatory- and gonadotropin-related processes at 10 months. In conclusion, we show that both wtHTT and mHTT overexpression change hypothalamic transcriptome profile, specifically mHTT, altering neuroendocrine circuits. In contrast, the ubiquitous expression of full-length mHTT in the BACHD hypothalamus moderately affects the transcriptomic profile.
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Soylu-Kucharz R, Khoshnan A, Petersén Å. IKKβ signaling mediates metabolic changes in the hypothalamus of a Huntington disease mouse model. iScience 2022; 25:103771. [PMID: 35146388 PMCID: PMC8819015 DOI: 10.1016/j.isci.2022.103771] [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] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 11/16/2021] [Accepted: 01/11/2022] [Indexed: 01/13/2023] Open
Abstract
Huntington disease (HD) is a neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin (HTT) gene. Metabolic changes are associated with HD progression, but underlying mechanisms are not fully known. As the IKKβ/NF-κB pathway is an essential regulator of metabolism, we investigated the involvement of IKKβ, the upstream activator of NF-κB in hypothalamus-specific HD metabolic changes. We expressed amyloidogenic N-terminal fragments of mutant HTT (mHTT) in the hypothalamus of mice with brain-specific ablation of IKKβ (Nestin/IKKβlox/lox) and control mice (IKKβlox/lox). We assessed effects on body weight, metabolic hormones, and hypothalamic neuropathology. Hypothalamic expression of mHTT led to an obese phenotype only in female mice. CNS-specific inactivation of IKKβ prohibited weight gain in females, which was independent of neuroprotection and microglial activation. Our study suggests that mHTT in the hypothalamus causes metabolic imbalance in a sex-specific fashion, and central inhibition of the IKKβ pathway attenuates the obese phenotype. Mutant huntingtin in the hypothalamus causes sex-specific metabolic imbalance CNS-specific inactivation of the IKKβ pathway prevents the obese phenotype IKKβ inactivation leads to an increased number of mutant huntingtin inclusions IKKβ inactivation does not prevent orexin or A13 TH neuron loss
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Affiliation(s)
- Rana Soylu-Kucharz
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, BMC D11, 22184 Lund, Sweden
| | - Ali Khoshnan
- California Institute of Technology, Pasadena, CA 91125, USA
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, BMC D11, 22184 Lund, Sweden
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4
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Hypothalamic expression of huntingtin causes distinct metabolic changes in Huntington's disease mice. Mol Metab 2022; 57:101439. [PMID: 35007790 PMCID: PMC8814380 DOI: 10.1016/j.molmet.2022.101439] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 01/05/2022] [Indexed: 11/29/2022] Open
Abstract
Objective In Huntington's disease (HD), the disease-causing huntingtin (HTT) protein is ubiquitously expressed and causes both central and peripheral pathology. In clinical HD, a higher body mass index has been associated with slower disease progression, indicating the role of metabolic changes in disease pathogenesis. Underlying mechanisms of metabolic changes in HD remain poorly understood, but recent studies suggest the involvement of hypothalamic dysfunction. The present study aimed to investigate whether modulation of hypothalamic HTT levels would affect metabolic phenotype and disease features in HD using mouse models. Methods We used the R6/2 and BACHD mouse models that express different lengths of mutant HTT to develop lean- and obese phenotypes, respectively. We utilized adeno-associated viral vectors to overexpress either mutant or wild-type HTT in the hypothalamus of R6/2, BACHD, and their wild-type littermates. The metabolic phenotype was assessed by body weight measurements over time and body composition analysis using dual-energy x-ray absorptiometry at the endpoint. R6/2 mice were further characterized using behavioral analyses, including rotarod, nesting-, and hindlimb clasping tests during early- and late-time points of disease progression. Finally, gene expression analysis was performed in R6/2 mice and wild-type littermates in order to assess transcriptional changes in the hypothalamus and adipose tissue. Results Hypothalamic overexpression of mutant HTT induced significant gender-affected body weight gain in all models, including wild-type mice. In R6/2 females, early weight gain shifted to weight loss during the corresponding late stage of disease despite increased fat accumulation. Body weight changes were accompanied by behavioral alterations. During the period of early weight gain, R6/2 mice displayed a comparable locomotor capacity to wild-type mice. When assessing behavior just prior to weight loss onset in R6/2 mice, decreased locomotor performance was observed in R6/2 females with hypothalamic overexpression of mutant HTT. Transcriptional downregulation of beta-3 adrenergic receptor (B3AR), adipose triglyceride lipase (ATGL), and peroxisome proliferator-activated receptor-gamma (PPARγ) in gonadal white adipose tissue was accompanied by distinct alterations in hypothalamic gene expression profiles in R6/2 females after mutant HTT overexpression. No significant effect on metabolic phenotype in R6/2 was seen in response to wild-type HTT overexpression. Conclusions Taken together, our findings provide further support for the role of HTT in metabolic control via hypothalamic neurocircuits. Understanding the specific central neurocircuits and their peripheral link underlying metabolic imbalance in HD may open up avenues for novel therapeutic interventions. Overexpression of hypothalamic huntingtin affects weight in Huntington's disease mice. Hypothalamic huntingtin expression results in gene expression changes in white fat and the hypothalamus. Hypothalamic huntingtin cannot prevent late-stage weight loss in R6/2 mice.
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5
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Androgen Reduces Mitochondrial Respiration in Mouse Brown Adipocytes: A Model for Disordered Energy Balance in Polycystic Ovary Syndrome. Int J Mol Sci 2020; 22:ijms22010243. [PMID: 33383677 PMCID: PMC7796281 DOI: 10.3390/ijms22010243] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 12/21/2020] [Accepted: 12/23/2020] [Indexed: 12/15/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) is a common endocrinopathy that is associated with an adverse metabolic profile including reduced postprandial thermogenesis. Although abnormalities in adipose tissue function have been widely reported in women with PCOS, less is known about direct effects of androgen on white and, particularly, brown adipocytes. The purpose of this study was to investigate the effect of the nonaromatizable androgen dihydrotestosterone (DHT) on (1) lipid accumulation and expression of adipogenic markers in immortalized mouse brown adipose cell lines (IMBATs), (2) mitochondrial respiration in IMBATs, (3) mitochondrial DNA content and gene expression, (4) expression of brown adipose tissue (BAT) markers and thermogenic activation. In addition, we profiled the relative levels of 38 adipokines secreted from BAT explants and looked at androgen effects on adipokine gene expression in both IMBATs and immortalized mouse white adipose (IMWATs) cell lines. Androgen treatment inhibited IMBAT differentiation in a dose-dependent manner, reduced markers of adipogenesis, and attenuated the β-adrenoceptor-stimulated increase in uncoupling protein-1 (UCP1) expression. In explants of mouse interscapular BAT, androgen reduced expression of UCP1, peroxisome proliferator-activated receptor-γ coactivator-1 (PCG-1) and Cidea. Significantly, as well as affecting genes involved in thermogenesis in BAT, androgen treatment reduced mitochondrial respiration in IMBATs, as measured by the Seahorse XF method. The results of this study suggest a role for excess androgen in inhibiting brown adipogenesis, attenuating the activation of thermogenesis and reducing mitochondrial respiration in BAT. Together, these data provide a plausible molecular mechanism that may contribute to reduced postprandial thermogenesis and the tendency to obesity in women with PCOS.
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Abstract
Since the discovery of functionally competent, energy-consuming brown adipose tissue (BAT) in adult humans, much effort has been devoted to exploring this tissue as a means for increasing energy expenditure to counteract obesity. However, despite promising effects on metabolic rate and insulin sensitivity, no convincing evidence for weight-loss effects of cold-activated human BAT exists to date. Indeed, increasing energy expenditure would naturally induce compensatory feedback mechanisms to defend body weight. Interestingly, BAT is regulated by multiple interactions with the hypothalamus from regions overlapping with centers for feeding behavior and metabolic control. Therefore, in the further exploration of BAT as a potential source of novel drug targets, we discuss the hypothalamic orchestration of BAT activity and the relatively unexplored BAT feedback mechanisms on neuronal regulation. With a holistic view on hypothalamic-BAT interactions, we aim to raise ideas and provide a new perspective on this circuit and highlight its clinical relevance.
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Affiliation(s)
- Jo B Henningsen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark;
| | - Camilla Scheele
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark;
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7
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Cheong RY, Gabery S, Petersén Å. The Role of Hypothalamic Pathology for Non-Motor Features of Huntington's Disease. J Huntingtons Dis 2020; 8:375-391. [PMID: 31594240 PMCID: PMC6839491 DOI: 10.3233/jhd-190372] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Huntington’s disease (HD) is a fatal genetic neurodegenerative disorder. It has mainly been considered a movement disorder with cognitive symptoms and these features have been associated with pathology of the striatum and cerebral cortex. Importantly, individuals with the mutant huntingtin gene suffer from a spectrum of non-motor features often decades before the motor disorder manifests. These symptoms and signs include a range of psychiatric symptoms, sleep problems and metabolic changes with weight loss particularly in later stages. A higher body mass index at diagnosis is associated with slower disease progression. The common psychiatric symptom of apathy progresses with the disease. The fact that non-motor features are present early in the disease and that they show an association to disease progression suggest that unravelling the underlying neurobiological mechanisms may uncover novel targets for early disease intervention and better symptomatic treatment. The hypothalamus and the limbic system are important brain regions that regulate emotion, social cognition, sleep and metabolism. A number of studies using neuroimaging, postmortem human tissue and genetic manipulation in animal models of the disease has collectively shown that the hypothalamus and the limbic system are affected in HD. These findings include the loss of neuropeptide-expressing neurons such as orexin (hypocretin), oxytocin, vasopressin, somatostatin and VIP, and increased levels of SIRT1 in distinct nuclei of the hypothalamus. This review provides a summary of the results obtained so far and highlights the potential importance of these changes for the understanding of non-motor features in HD.
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Affiliation(s)
- Rachel Y Cheong
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Sanaz Gabery
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
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8
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Petkau TL, Hill A, Connolly C, Lu G, Wagner P, Kosior N, Blanco J, Leavitt BR. Mutant huntingtin expression in microglia is neither required nor sufficient to cause the Huntington's disease-like phenotype in BACHD mice. Hum Mol Genet 2020; 28:1661-1670. [PMID: 30624705 DOI: 10.1093/hmg/ddz009] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 12/10/2018] [Accepted: 12/31/2018] [Indexed: 12/27/2022] Open
Abstract
Huntington's disease (HD) is caused by a CAG repeat expansion in the HTT gene and is characterized by early and selective striatal neurodegeneration. The huntingtin (HTT) protein is ubiquitously expressed in many tissues and the cellular pathogenesis of the disease is not fully understood. Immune cell dysfunction due to mutant HTT (mHTT) expression and aberrant immune system activation in HD patients suggests that inflammatory processes may contribute to HD pathogenesis. Here we used the BACHD mouse model of HD, which carries a conditional transgene expressing full-length human mHTT, to selectively deplete mHTT expression in myeloid lineage cells, including microglia, and evaluated the effects on HD-related behavior and neuropathology. In the converse experiment, we depleted mHTT expression in the majority of cells in the brain but specifically excluding microglia and again evaluated behavior and neuropathology. In mice with myeloid-specific mHTT-depletion, we observed no significant rescue of any behavioral or neuropathological outcome measures, while neural-specific knockout mice showed significant rescue of body weight, rotarod performance and striatal volume. We conclude that mHTT expression in microglia, though clearly affecting specific aspects of microglia function, does not alter disease pathogenesis in the BACHD mouse model. This may have implications for current or future therapeutic trials testing immune-modulating drugs in HD patients.
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Affiliation(s)
- Terri L Petkau
- Centre for Molecular Medicine & Therapeutics, Department of Medical Genetics, University of British Columbia, and Children's and Women's Hospital, Vancouver, BC, Canada
| | - Austin Hill
- Centre for Molecular Medicine & Therapeutics, Department of Medical Genetics, University of British Columbia, and Children's and Women's Hospital, Vancouver, BC, Canada
| | - Colúm Connolly
- Centre for Molecular Medicine & Therapeutics, Department of Medical Genetics, University of British Columbia, and Children's and Women's Hospital, Vancouver, BC, Canada
| | - Ge Lu
- Centre for Molecular Medicine & Therapeutics, Department of Medical Genetics, University of British Columbia, and Children's and Women's Hospital, Vancouver, BC, Canada
| | - Pam Wagner
- Centre for Molecular Medicine & Therapeutics, Department of Medical Genetics, University of British Columbia, and Children's and Women's Hospital, Vancouver, BC, Canada
| | - Natalia Kosior
- Centre for Molecular Medicine & Therapeutics, Department of Medical Genetics, University of British Columbia, and Children's and Women's Hospital, Vancouver, BC, Canada
| | - Jake Blanco
- Centre for Molecular Medicine & Therapeutics, Department of Medical Genetics, University of British Columbia, and Children's and Women's Hospital, Vancouver, BC, Canada
| | - Blair R Leavitt
- Centre for Molecular Medicine & Therapeutics, Department of Medical Genetics, University of British Columbia, and Children's and Women's Hospital, Vancouver, BC, Canada.,Division of Neurology, Department of Medicine, University of British Columbia Hospital, Wesbrook Mall, Vancouver, BC, Canada.,Brain Research Centre, University of British Columbia, Vancouver, BC, Canada
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Altıner Ş, Ardic S, Çebi AH. Extending the Phenotypic Spectrum of Huntington Disease: Hypothermia. Mol Syndromol 2020; 11:56-58. [PMID: 32256303 PMCID: PMC7109404 DOI: 10.1159/000505887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2019] [Indexed: 12/13/2022] Open
Abstract
Huntington disease (HD) is an autosomal dominant progressive neurodegenerative disorder associated with expanded CAG repeat size in the huntingtin gene and usually presenting with movement disorder, psychiatric symptoms, and cognitive decline. Sleep problems, weight loss, and cachexia are also common. Here, we report a patient presenting with hypothermia in late-stage HD. Although thermoregulatory defects were documented in animal models, this is the first report describing HD with hypothermia in humans.
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Affiliation(s)
- Şule Altıner
- Department of Medical Genetics, Trabzon Kanuni Training and Research Hospital, University of Health Sciences, Trabzon, Turkey
| | - Senol Ardic
- Department of Emergency Medicine, Faculty of Medicine, University of Health Sciences, Trabzon, Turkey
| | - Alper H. Çebi
- Department of Medical Genetics, Karadeniz Technical University School of Medicine, Trabzon, Turkey
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10
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Peripheral Expression of Mutant Huntingtin is a Critical Determinant of Weight Loss and Metabolic Disturbances in Huntington's Disease. Sci Rep 2019; 9:10127. [PMID: 31300691 PMCID: PMC6626032 DOI: 10.1038/s41598-019-46470-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 06/26/2019] [Indexed: 12/31/2022] Open
Abstract
Deteriorating weight loss in patients with Huntington’s disease (HD) is a complicated peripheral manifestation and the cause remains poorly understood. Studies suggest that body weight strongly influences the clinical progression rate of HD and thereby offers a valuable target for therapeutic interventions. Mutant huntingtin (mHTT) is ubiquitously expressed and could induce toxicity by directly acting in the peripheral tissues. We investigated the effects of selective expression of mHTT exon1 in fat body (FB; functionally equivalent to human adipose tissue and liver) using transgenic Drosophila. We find that FB-autonomous expression of mHTT exon1 is intrinsically toxic and causes chronic weight loss in the flies despite progressive hyperphagia, and early adult death. Moreover, flies exhibit loss of intracellular lipid stores, and decline in the systemic levels of lipids and carbohydrates which aggravates over time, representing metabolic defects. At the cellular level, besides impairment, cell death also occurs with the formation of mHTT aggregates in the FB. These findings indicate that FB-autonomous expression of mHTT alone is sufficient to cause metabolic abnormalities and emaciation in vivo without any neurodegenerative cues.
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11
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Baldo B, Gabery S, Soylu-Kucharz R, Cheong RY, Henningsen JB, Englund E, McLean C, Kirik D, Halliday G, Petersén Å. SIRT1 is increased in affected brain regions and hypothalamic metabolic pathways are altered in Huntington disease. Neuropathol Appl Neurobiol 2018; 45:361-379. [PMID: 30019499 DOI: 10.1111/nan.12514] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 07/11/2018] [Indexed: 01/03/2023]
Abstract
AIMS Metabolic dysfunction is involved in modulating the disease process in Huntington disease (HD) but the underlying mechanisms are not known. The aim of this study was to investigate if the metabolic regulators sirtuins are affected in HD. METHODS Quantitative real-time polymerase chain reactions were used to assess levels of SIRT1-3 and downstream targets in post mortem brain tissue from HD patients and control cases as well as after selective hypothalamic expression of mutant huntingtin (HTT) using recombinant adeno-associated viral vectors in mice. RESULTS We show that mRNA levels of the metabolic regulator SIRT1 are increased in the striatum and the cerebral cortex but not in the less affected cerebellum in post mortem HD brains. Levels of SIRT2 are only increased in the striatum and SIRT3 is not affected in HD. Interestingly, mRNA levels of SIRT1 are selectively increased in the lateral hypothalamic area (LHA) and ventromedial hypothalamus (VMH) in HD. Further analyses of the LHA and VMH confirmed pathological changes in these regions including effects on SIRT1 downstream targets and reduced mRNA levels of orexin (hypocretin), prodynorphin and melanin-concentrating hormone (MCH) in the LHA and of brain-derived neurotrophic factor (BDNF) in the VMH. Analyses after selective hypothalamic expression of mutant HTT suggest that effects on BDNF, orexin, dynorphin and MCH are early and direct, whereas changes in SIRT1 require more widespread expression of mutant HTT. CONCLUSIONS We show that SIRT1 expression is increased in HD-affected brain regions and that metabolic pathways are altered in the HD hypothalamus.
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Affiliation(s)
- B Baldo
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - S Gabery
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - R Soylu-Kucharz
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - R Y Cheong
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - J B Henningsen
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - E Englund
- Division of Oncology and Pathology, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - C McLean
- Department of Pathology, Alfred Hospital, Melbourne, Vic, Australia
| | - D Kirik
- B.R.A.I.N.S. Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - G Halliday
- Brain and Mind Centre, Sydney Medical School, UNSW Medicine and NeuRA, The University of Sydney, Sydney, NSW, Australia
| | - Å Petersén
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
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12
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Vercruysse P, Vieau D, Blum D, Petersén Å, Dupuis L. Hypothalamic Alterations in Neurodegenerative Diseases and Their Relation to Abnormal Energy Metabolism. Front Mol Neurosci 2018; 11:2. [PMID: 29403354 PMCID: PMC5780436 DOI: 10.3389/fnmol.2018.00002] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 01/03/2018] [Indexed: 12/11/2022] Open
Abstract
Neurodegenerative diseases (NDDs) are disorders characterized by progressive deterioration of brain structure and function. Selective neuronal populations are affected leading to symptoms which are prominently motor in amyotrophic lateral sclerosis (ALS) or Huntington’s disease (HD), or cognitive in Alzheimer’s disease (AD) and fronto-temporal dementia (FTD). Besides the common existence of neuronal loss, NDDs are also associated with metabolic changes such as weight gain, weight loss, loss of fat mass, as well as with altered feeding behavior. Importantly, preclinical research as well as clinical studies have demonstrated that altered energy homeostasis influences disease progression in ALS, AD and HD, suggesting that identification of the pathways leading to perturbed energy balance might provide valuable therapeutic targets Signals from both the periphery and central inputs are integrated in the hypothalamus, a major hub for the control of energy balance. Recent research identified major hypothalamic changes in multiple NDDs. Here, we review these hypothalamic alterations and seek to identify commonalities and differences in hypothalamic involvement between the different NDDs. These hypothalamic defects could be key in the development of perturbations in energy homeostasis in NDDs and further understanding of the underlying mechanisms might open up new avenues to not only treat weight loss but also to ameliorate overall neurological symptoms.
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Affiliation(s)
- Pauline Vercruysse
- UMR-S 1118, Faculté de Médecine, Institut National de la Santé et de la Recherche Médicale (INSERM), Strasbourg, France.,UMR-S1118, Université de Strasbourg, Strasbourg, France.,Department of Neurology, Ulm University, Ulm, Germany
| | - Didier Vieau
- UMR-S 1172-JPArc, Centre Hospitalier Régional Universitaire de Lille (CHRU de Lille), Alzheimer and Tauopathies, Lille, France
| | - David Blum
- UMR-S 1172-JPArc, Centre Hospitalier Régional Universitaire de Lille (CHRU de Lille), Alzheimer and Tauopathies, Lille, France
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit (TNU), Lund University, Lund, Sweden
| | - Luc Dupuis
- UMR-S 1118, Faculté de Médecine, Institut National de la Santé et de la Recherche Médicale (INSERM), Strasbourg, France.,UMR-S1118, Université de Strasbourg, Strasbourg, France
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Weydt P, Dupuis L, Petersen Å. Thermoregulatory disorders in Huntington disease. HANDBOOK OF CLINICAL NEUROLOGY 2018; 157:761-775. [PMID: 30459039 DOI: 10.1016/b978-0-444-64074-1.00047-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Huntington disease (HD) is a paradigmatic autosomal-dominant adult-onset neurodegenerative disease. Since the identification of an abnormal expansion of a trinucleotide repeat tract in the huntingtin gene as the underlying genetic defect, a broad range of transgenic animal models of the disease has become available and these have helped to unravel the relevant molecular pathways in unprecedented detail. Of note, some of the most informative of these models develop thermoregulatory defects such as hypothermia, problems with adaptive thermogenesis, and an altered circadian temperature rhythm. Both central, e.g., in the hypothalamus and peripheral, i.e., the brown adipose tissue and skeletal muscle, problems contribute to the phenotype. Importantly, these structures and pathways are also affected in human HD. Yet, currently the evidence for bona fide thermodysregulation in human HD patients remains anecdotal. This may be due to a lack of reliable tools for monitoring body temperature in an outpatient setting. Regardless, study of the temperature phenotype has contributed to the identification of unexpected molecular targets, such as the PGC-1α pathway.
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Affiliation(s)
- Patrick Weydt
- Department of Neurodegenerative Diseases and Gerontopsychiatry/Neurology, University of Bonn Medical Center, Bonn, Germany.
| | - Luc Dupuis
- Faculty of Medicine, University of Strasbourg, Strasbourg, France
| | - Åsa Petersen
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Sciences, Lund University, Lund, Sweden
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14
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Sebastianutto I, Cenci MA, Fieblinger T. Alterations of striatal indirect pathway neurons precede motor deficits in two mouse models of Huntington's disease. Neurobiol Dis 2017; 105:117-131. [PMID: 28578004 DOI: 10.1016/j.nbd.2017.05.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 04/26/2017] [Accepted: 05/29/2017] [Indexed: 11/15/2022] Open
Abstract
Striatal neurons forming the indirect pathway (iSPNs) are particularly vulnerable in Huntington's disease (HD). In this study we set out to investigate morphological and physiological alterations of iSPNs in two mouse models of HD with relatively slow disease progression (long CAG repeat R6/2 and zQ175-KI). Both were crossed with a transgenic mouse line expressing eGFP in iSPNs. Using the open-field and rotarod tests, we first defined two time points in relation to the occurrence of motor deficits in each model. Then, we investigated electrophysiological and morphological properties of iSPNs at both ages. Both HD models exhibited increased iSPN excitability already before the onset of motor deficits, associated with a reduced number of primary dendrites and decreased function of Kir- and voltage-gated potassium channels. Alterations that specifically occurred at symptomatic ages included increased calcium release by back-propagating action potentials in proximal dendrites, due to enhanced engagement of intracellular calcium stores. Moreover, motorically impaired mice of both HD models showed a reduction in iSPN spine density and progressive formation of huntingtin (Htt) aggregates in the striatum. Our study therefore reports iSPN-specific alterations relative to the development of a motor phenotype in two different mouse models of HD. While some alterations occur early and are partly non-progressive, others potentially provide a pathophysiological marker of an overt disease state.
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Affiliation(s)
- Irene Sebastianutto
- Basal Ganglia Pathophysiology Unit, Dept. of Experimental Medical Science, Lund University, 22184 Lund, Sweden
| | - Maria Angela Cenci
- Basal Ganglia Pathophysiology Unit, Dept. of Experimental Medical Science, Lund University, 22184 Lund, Sweden
| | - Tim Fieblinger
- Basal Ganglia Pathophysiology Unit, Dept. of Experimental Medical Science, Lund University, 22184 Lund, Sweden.
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