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Stark R. The olfactory bulb: A neuroendocrine spotlight on feeding and metabolism. J Neuroendocrinol 2024; 36:e13382. [PMID: 38468186 DOI: 10.1111/jne.13382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 02/22/2024] [Accepted: 02/25/2024] [Indexed: 03/13/2024]
Abstract
Olfaction is the most ancient sense and is needed for food-seeking, danger protection, mating and survival. It is often the first sensory modality to perceive changes in the external environment, before sight, taste or sound. Odour molecules activate olfactory sensory neurons that reside on the olfactory epithelium in the nasal cavity, which transmits this odour-specific information to the olfactory bulb (OB), where it is relayed to higher brain regions involved in olfactory perception and behaviour. Besides odour processing, recent studies suggest that the OB extends its function into the regulation of food intake and energy balance. Furthermore, numerous hormone receptors associated with appetite and metabolism are expressed within the OB, suggesting a neuroendocrine role outside the hypothalamus. Olfactory cues are important to promote food preparatory behaviours and consumption, such as enhancing appetite and salivation. In addition, altered metabolism or energy state (fasting, satiety and overnutrition) can change olfactory processing and perception. Similarly, various animal models and human pathologies indicate a strong link between olfactory impairment and metabolic dysfunction. Therefore, understanding the nature of this reciprocal relationship is critical to understand how olfactory or metabolic disorders arise. This present review elaborates on the connection between olfaction, feeding behaviour and metabolism and will shed light on the neuroendocrine role of the OB as an interface between the external and internal environments. Elucidating the specific mechanisms by which olfactory signals are integrated and translated into metabolic responses holds promise for the development of targeted therapeutic strategies and interventions aimed at modulating appetite and promoting metabolic health.
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Affiliation(s)
- Romana Stark
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Victoria, Australia
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2
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Sweat SC, Cheetham CEJ. Deficits in olfactory system neurogenesis in neurodevelopmental disorders. Genesis 2024; 62:e23590. [PMID: 38490949 PMCID: PMC10990073 DOI: 10.1002/dvg.23590] [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: 11/15/2023] [Revised: 02/07/2024] [Accepted: 02/26/2024] [Indexed: 03/17/2024]
Abstract
The role of neurogenesis in neurodevelopmental disorders (NDDs) merits much attention. The complex process by which stem cells produce daughter cells that in turn differentiate into neurons, migrate various distances, and form synaptic connections that are then refined by neuronal activity or experience is integral to the development of the nervous system. Given the continued postnatal neurogenesis that occurs in the mammalian olfactory system, it provides an ideal model for understanding how disruptions in distinct stages of neurogenesis contribute to the pathophysiology of various NDDs. This review summarizes and discusses what is currently known about the disruption of neurogenesis within the olfactory system as it pertains to attention-deficit/hyperactivity disorder, autism spectrum disorder, Down syndrome, Fragile X syndrome, and Rett syndrome. Studies included in this review used either human subjects, mouse models, or Drosophila models, and lay a compelling foundation for continued investigation of NDDs by utilizing the olfactory system.
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Affiliation(s)
- Sean C Sweat
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Claire E J Cheetham
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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3
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Jacobson PT, Vilarello BJ, Tervo JP, Waring NA, Gudis DA, Goldberg TE, Devanand DP, Overdevest JB. Associations between olfactory dysfunction and cognition: a scoping review. J Neurol 2024; 271:1170-1203. [PMID: 38217708 PMCID: PMC11144520 DOI: 10.1007/s00415-023-12057-7] [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: 07/20/2023] [Revised: 10/10/2023] [Accepted: 10/11/2023] [Indexed: 01/15/2024]
Abstract
INTRODUCTION Strong evidence suggests that olfactory dysfunction (OD) can predict additional neurocognitive decline in neurodegenerative conditions such as Alzheimer's and Parkinson's diseases. However, research exploring olfaction and cognition in younger populations is limited. The aim of this review is to evaluate cognitive changes among non-elderly adults with non-COVID-19-related OD. METHODS We performed a structured comprehensive literature search of PubMed, Ovid Embase, Web of Science, and Cochrane Library in developing this scoping review. The primary outcome of interest was the association between OD and cognitive functioning in adults less than 60 years of age. RESULTS We identified 2878 studies for title and abstract review, with 167 undergoing full text review, and 54 selected for data extraction. Of these, 34 studies reported on populations of individuals restricted to the ages of 18-60, whereas the remaining 20 studies included a more heterogeneous population with the majority of individuals in this target age range in addition to some above the age of 60. The etiologies for smell loss among the included studies were neuropsychiatric disorders (37%), idiopathic cause (25%), type 2 diabetes (7%), trauma (5%), infection (4%), intellectual disability (4%), and other (18%). Some studies reported numerous associations and at times mixed, resulting in a total number of associations greater than the included number of 54 studies. Overall, 21/54 studies demonstrated a positive association between olfaction and cognition, 7/54 demonstrated no association, 25/54 reported mixed results, and only 1/54 demonstrated a negative association. CONCLUSION Most studies demonstrate a positive correlation between OD and cognition, but the data are mixed with associations less robust in this young adult population compared to elderly adults. Despite the heterogeneity in study populations and outcomes, this scoping review serves as a starting point for further investigation on this topic. Notably, as many studies in this review involved disorders that may have confounding effects on both olfaction and cognition, future research should control for these confounders and incorporate non-elderly individuals with non-psychiatric causes of smell loss.
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Affiliation(s)
- Patricia T Jacobson
- Department of Otolaryngology-Head and Neck Surgery, New York-Presbyterian/Columbia University Irving Medical Center, New York, NY, USA
| | - Brandon J Vilarello
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Jeremy P Tervo
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Nicholas A Waring
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - David A Gudis
- Department of Otolaryngology-Head and Neck Surgery, New York-Presbyterian/Columbia University Irving Medical Center, New York, NY, USA
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Terry E Goldberg
- Department of Psychiatry, New York-Presbyterian/Columbia University Irving Medical Center, New York, NY, USA
| | - D P Devanand
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
- Department of Psychiatry, New York-Presbyterian/Columbia University Irving Medical Center, New York, NY, USA
| | - Jonathan B Overdevest
- Department of Otolaryngology-Head and Neck Surgery, New York-Presbyterian/Columbia University Irving Medical Center, New York, NY, USA.
- Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
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Brozzetti L, Scambi I, Bertoldi L, Zanini A, Malacrida G, Sacchetto L, Baldassa L, Benvenuto G, Mariotti R, Zanusso G, Cecchini MP. RNAseq analysis of olfactory neuroepithelium cytological samples in individuals with Down syndrome compared to euploid controls: a pilot study. Neurol Sci 2023; 44:919-930. [PMID: 36394661 PMCID: PMC9925603 DOI: 10.1007/s10072-022-06500-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 11/05/2022] [Indexed: 11/18/2022]
Abstract
Down syndrome is a common genetic disorder caused by partial or complete triplication of chromosome 21. This syndrome shows an overall and progressive impairment of olfactory function, detected early in adulthood. The olfactory neuronal cells are located in the nasal olfactory mucosa and represent the first sensory neurons of the olfactory pathway. Herein, we applied the olfactory swabbing procedure to allow a gentle collection of olfactory epithelial cells in seven individuals with Down syndrome and in ten euploid controls. The aim of this research was to investigate the peripheral gene expression pattern in olfactory epithelial cells through RNAseq analysis. Validated tests (Sniffin' Sticks Extended test) were used to assess olfactory function. Olfactory scores were correlated with RNAseq results and cognitive scores (Vineland II and Leiter scales). All Down syndrome individuals showed both olfactory deficit and intellectual disability. Down syndrome individuals and euploid controls exhibited clear expression differences in genes located in and outside the chromosome 21. In addition, a significant correlation was found between olfactory test scores and gene expression, while a non-significant correlation emerged between olfactory and cognitive scores. This first preliminary step gives new insights into the Down syndrome olfactory system research, starting from the olfactory neuroepithelium, the first cellular step on the olfactory way.
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Affiliation(s)
- Lorenzo Brozzetti
- Department of Neurosciences, Biomedicine and Movement Sciences, Neurology Unit, University of Verona, Verona, Italy
| | - Ilaria Scambi
- Department of Neurosciences, Biomedicine and Movement Sciences, Anatomy and Histology Section, University of Verona, Strada Le Grazie 8, 37134, Verona, Italy
| | | | - Alice Zanini
- Department of Neurosciences, Biomedicine and Movement Sciences, Anatomy and Histology Section, University of Verona, Strada Le Grazie 8, 37134, Verona, Italy
| | | | - Luca Sacchetto
- Department of Surgery, Dentistry, Paediatrics and Gynaecology, Otolaryngology Section, University of Verona, Verona, Italy
| | - Lucia Baldassa
- AGBD, Associazione Sindrome di Down, Onlus, Verona, Italy
| | | | - Raffaella Mariotti
- Department of Neurosciences, Biomedicine and Movement Sciences, Anatomy and Histology Section, University of Verona, Strada Le Grazie 8, 37134, Verona, Italy
| | - Gianluigi Zanusso
- Department of Neurosciences, Biomedicine and Movement Sciences, Neurology Unit, University of Verona, Verona, Italy
| | - Maria Paola Cecchini
- Department of Neurosciences, Biomedicine and Movement Sciences, Anatomy and Histology Section, University of Verona, Strada Le Grazie 8, 37134, Verona, Italy.
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5
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Gomes FDC, Santos IBF, Stephani CM, Ferrari MDFR, Galvis-Alonso OY, Goloni-Bertollo EM, Melo-Neto JSD, Pavarino ÉC. Vitamin D3 supplementation may attenuate morphological and molecular abnormalities of the olfactory bulb in a mouse model of Down syndrome. Tissue Cell 2022; 78:101898. [DOI: 10.1016/j.tice.2022.101898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 08/12/2022] [Accepted: 08/13/2022] [Indexed: 11/28/2022]
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6
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Lee SJ. Alzheimer’s Disease is a Result of Loss of Full Brain Buoyancy. Med Hypotheses 2022. [DOI: 10.1016/j.mehy.2022.110857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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7
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Di Schiavi E, Vistoli G, Moretti RM, Corrado I, Zuccarini G, Gervasoni S, Casati L, Bottai D, Merlo GR, Maggi R. Anosmin-1-Like Effect of UMODL1/Olfactorin on the Chemomigration of Mouse GnRH Neurons and Zebrafish Olfactory Axons Development. Front Cell Dev Biol 2022; 10:836179. [PMID: 35223856 PMCID: PMC8874799 DOI: 10.3389/fcell.2022.836179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 01/17/2022] [Indexed: 11/13/2022] Open
Abstract
The impairment of development/migration of hypothalamic gonadotropin-releasing hormone (GnRH) neurons is the main cause of Kallmann's syndrome (KS), an inherited disorder characterized by hypogonadism, anosmia, and other developmental defects. Olfactorin is an extracellular matrix protein encoded by the UMODL1 (uromodulin-like 1) gene expressed in the mouse olfactory region along the migratory route of GnRH neurons. It shares a combination of WAP and FNIII repeats, expressed in complementary domains, with anosmin-1, the product of the ANOS1 gene, identified as the causative of KS. In the present study, we have investigated the effects of olfactorin in vitro and in vivo models. The results show that olfactorin exerts an anosmin-1-like strong chemoattractant effect on mouse-immortalized GnRH neurons (GN11 cells) through the activation of the FGFR and MAPK pathways. In silico analysis of olfactorin and anosmin-1 reveals a satisfactory similarity at the N-terminal region for the overall arrangement of corresponding WAP and FNIII domains and marked similarities between WAP domains’ binding modes of interaction with the resolved FGFR1–FGF2 complex. Finally, in vivo experiments show that the down-modulation of the zebrafish z-umodl1 gene (orthologous of UMODL1) in both GnRH3:GFP and omp2k:gap-CFPrw034 transgenic zebrafish strains leads to a clear disorganization and altered fasciculation of the neurites of GnRH3:GFP neurons crossing at the anterior commissure and a significant increase in olfactory CFP + fibers with altered trajectory. Thus, our study shows olfactorin as an additional factor involved in the development of olfactory and GnRH systems and proposes UMODL1 as a gene worthy of diagnostic investigation in KS.
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Affiliation(s)
- Elia Di Schiavi
- Institute of Biosciences and Bioresources, National Research Council of Italy, Naples, Italy
| | - Giulio Vistoli
- Department of Pharmaceutical Sciences DISFARM, Università degli Studi di Milano, Milano, Italy
| | - Roberta Manuela Moretti
- Department of Pharmacological and Biomolecular Sciences DISFEB, Università degli Studi di Milano, Milano, Italy
| | - Ilaria Corrado
- Department Molecular Biotechnology and Health Science, University of Torino, Torino, Italy
| | - Giulia Zuccarini
- Department Molecular Biotechnology and Health Science, University of Torino, Torino, Italy
| | - Silvia Gervasoni
- Department of Pharmaceutical Sciences DISFARM, Università degli Studi di Milano, Milano, Italy
| | - Lavinia Casati
- Department of Pharmaceutical Sciences DISFARM, Università degli Studi di Milano, Milano, Italy
| | - Daniele Bottai
- Department of Pharmaceutical Sciences DISFARM, Università degli Studi di Milano, Milano, Italy
| | - Giorgio Roberto Merlo
- Department Molecular Biotechnology and Health Science, University of Torino, Torino, Italy
| | - Roberto Maggi
- Department of Pharmaceutical Sciences DISFARM, Università degli Studi di Milano, Milano, Italy
- *Correspondence: Roberto Maggi,
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Windsperger K, Hoehl S. Development of Down Syndrome Research Over the Last Decades-What Healthcare and Education Professionals Need to Know. Front Psychiatry 2021; 12:749046. [PMID: 34970162 PMCID: PMC8712441 DOI: 10.3389/fpsyt.2021.749046] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 11/22/2021] [Indexed: 11/13/2022] Open
Abstract
Down syndrome (DS) is the most prevalent neurodevelopmental disorder, with a known genetic cause. Besides facial dysmorphologies and congenital and/or acquired medical conditions, the syndrome is characterized by intellectual disability, accelerated aging, and an increased likelihood of an early onset Alzheimer's disease in adulthood. These common patterns of DS are derived from the long-held standard in the field of DS research, that describes individuals with DS as a homogeneous group and compares phenotypic outcomes with either neurotypical controls or other neurodevelopmental disorders. This traditional view has changed, as modern research pinpoints a broad variability in both the occurrence and severity of symptoms across DS, arguing for DS heterogeneity and against a single "DS profile." Nevertheless, prenatal counseling does not often prioritize the awareness of potential within-group variations of DS, portraying only a vague picture of the developmental outcomes of children with DS to expectant parents. This mini-review provides a concise update on existent information about the heterogeneity of DS from a full-spectrum developmental perspective, within an interdisciplinary context. Knowledge on DS heterogeneity will not only enable professionals to enhance the quality of prenatal counseling, but also help parents to set targeted early interventions, to further optimize daily functions and the quality of life of their children.
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Affiliation(s)
- Karin Windsperger
- Division of Obstetrics and Feto-Maternal Medicine, Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria
| | - Stefanie Hoehl
- Research Unit Developmental Psychology, Department of Developmental and Educational Psychology, Faculty of Psychology, University of Vienna, Vienna, Austria
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9
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Ageing and Olfactory Dysfunction in Trisomy 21: A Systematic Review. Brain Sci 2021; 11:brainsci11070952. [PMID: 34356186 PMCID: PMC8305843 DOI: 10.3390/brainsci11070952] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/27/2021] [Accepted: 07/07/2021] [Indexed: 12/14/2022] Open
Abstract
Purpose: The olfactory system is particularly vulnerable in an ageing brain, both anatomically and functionally, and these brain changes are more pronounced among individuals with trisomy 21. Furthermore, the age of the system starts to deteriorate, and the mechanism involved is unclear in an individual with trisomy 21. Therefore, the present review aims to summarise the available information related to this topic and to suggest questions still unanswered which can be a subject of further research. Methods: A systematic literature search of trisomy 21 and olfactory dysfunction was conducted using PubMed/MEDLINE and Scopus electronic database following PRISMA guidelines. References and citations were checked in the Google Scholar database. Reports were extracted for information on demographics and psychophysical evaluation. Then, the reports were systematically reviewed based on the effects of ageing on the three olfactory domains: threshold, discrimination, and identification. Results: Participants with trisomy 21 show an early onset of olfactory impairment, and the age effect of the olfactory deficit is fully expressed at age > 30 years old. The three olfactory domains, threshold, discrimination, and identification, are suggested to be impaired in trisomy 21 participants with age > 30 years old. Conclusions: Olfactory dysfunction in an individual with trisomy 21 commences at a relatively young age and affects the three olfactory domains. A challenge for the future is to quantitatively establish the olfactory function of an individual with trisomy 21 at all ages with more detailed measurements to further understand the pathophysiology of this brain deterioration.
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10
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Piriform cortex alterations in the Ts65Dn model for down syndrome. Brain Res 2020; 1747:147031. [PMID: 32726601 DOI: 10.1016/j.brainres.2020.147031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 07/02/2020] [Accepted: 07/22/2020] [Indexed: 11/22/2022]
Abstract
The piriform cortex is involved in olfactory information processing, that is altered in Down Syndrome. Moreover, piriform cortex has a crucial involvement in epilepsy generation and is one of the first regions affected in Alzheimer's Disease, both maladies being prevalent among Down Syndrome individuals. In this work, we studied the alterations in neuronal morphology, synaptology and structural plasticity in the piriform cortex of the Ts65Dn mouse model, which is the most used model for the study of this syndrome and mimics some of their alterations. We have observed that Ts65Dn piriform cortex displays: a reduction in dendritic arborisation, a higher density of inhibitory synapses (GAD67), a lower density of excitatory synapses (vGLUT1) and a higher density of inhibitory postsynaptic puncta (gephyrin). Under electron microscopy the excitatory presynaptic and postsynaptic elements were larger in trisomic mice than in controls. Similar results were obtained using confocal microscopy. There were less immature neurons in piriform cortex layer II in addition to a reduction in the expression of PSA-NCAM in the neuropil that subsequently can reflect impairment in structural plasticity. These data support the idea of an impaired environment with altered ratio of inhibition and excitation that involves a reduction in plasticity and dendritic atrophy, providing a possible substrate for the olfactory processing impairment observed in DS individuals.
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11
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Kondo K, Kikuta S, Ueha R, Suzukawa K, Yamasoba T. Age-Related Olfactory Dysfunction: Epidemiology, Pathophysiology, and Clinical Management. Front Aging Neurosci 2020; 12:208. [PMID: 32733233 PMCID: PMC7358644 DOI: 10.3389/fnagi.2020.00208] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/12/2020] [Indexed: 12/21/2022] Open
Abstract
Like other sensory systems, olfactory function deteriorates with age. Epidemiological studies have revealed that the incidence of olfactory dysfunction increases at the age of 60 and older and males are more affected than females. Moreover, smoking, heavy alcohol use, sinonasal diseases, and Down’s syndrome are associated with an increased incidence of olfactory dysfunction. Although the pathophysiology of olfactory dysfunction in humans remains largely unknown, studies in laboratory animals have demonstrated that both the peripheral and central olfactory nervous systems are affected by aging. Aged olfactory neuroepithelium in the nasal cavity shows the loss of mature olfactory neurons, replacement of olfactory neuroepithelium by respiratory epithelium, and a decrease in basal cell proliferation both in the normal state and after injury. In the central olfactory pathway, a decrease in the turnover of interneurons in the olfactory bulb (OB) and reduced activity in the olfactory cortex under olfactory stimulation is observed. Recently, the association between olfactory impairment and neurodegenerative diseases, such as Alzheimer’s disease (AD) and Parkinson’s disease (PD), has gained attention. Evidence-based pharmacotherapy to suppress or improve age-related olfactory dysfunction has not yet been established, but preliminary results suggest that olfactory training using odorants may be useful to improve some aspects of age-related olfactory impairment.
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Affiliation(s)
- Kenji Kondo
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Shu Kikuta
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Rumi Ueha
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Keigo Suzukawa
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Tatsuya Yamasoba
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
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12
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Bontempi P, Cisterna B, Malatesta M, Nicolato E, Mucignat-Caretta C, Zancanaro C. A smaller olfactory bulb in a mouse model of Down syndrome. Acta Neurobiol Exp (Wars) 2020. [DOI: 10.21307/ane-2020-034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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13
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Doty RL, Hawkes CH. Chemosensory dysfunction in neurodegenerative diseases. HANDBOOK OF CLINICAL NEUROLOGY 2019; 164:325-360. [PMID: 31604557 DOI: 10.1016/b978-0-444-63855-7.00020-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A number of neurodegenerative diseases are accompanied by disordered smell function. The degree of dysfunction can vary among different diseases, such that olfactory testing can aid in differentiating, for example, Alzheimer's disease (AD) from major affective disorder and Parkinson's disease (PD) from progressive supranuclear palsy. Unfortunately, altered smell function often goes unrecognized by patients and physicians alike until formal testing is undertaken. Such testing uniquely probes brain regions not commonly examined in physical examinations and can identify, in some cases, patients who are already in the "preclinical" stage of disease. Awareness of this fact is one reason why the Quality Standards Committee of the American Academy of Neurology has designated smell dysfunction as one of the key diagnostic criteria for PD. The same recommendation has been made by the Movement Disorder Society for both the diagnosis of PD and identification of prodromal PD. Similar suggestions are proposed to include olfactory dysfunction as an additional research criterion for the diagnosis of AD. Although taste impairment, i.e., altered sweet, sour, bitter, salty, and umami perception, has also been demonstrated in some disorders, taste has received much less scientific attention than smell. In this review, we assess what is known about the smell and taste disorders of a wide range of neurodegenerative diseases and describe studies seeking to understand their pathologic underpinnings.
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Affiliation(s)
- Richard L Doty
- Smell and Taste Center and Department of Otorhinolaryngology: Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.
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Huo HQ, Qu ZY, Yuan F, Ma L, Yao L, Xu M, Hu Y, Ji J, Bhattacharyya A, Zhang SC, Liu Y. Modeling Down Syndrome with Patient iPSCs Reveals Cellular and Migration Deficits of GABAergic Neurons. Stem Cell Reports 2018. [PMID: 29526735 PMCID: PMC5998838 DOI: 10.1016/j.stemcr.2018.02.001] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The brain of Down syndrome (DS) patients exhibits fewer interneurons in the cerebral cortex, but its underlying mechanism remains unknown. By morphometric analysis of cortical interneurons generated from DS and euploid induced pluripotent stem cells (iPSCs), we found that DS GABA neurons are smaller and with fewer neuronal processes. The proportion of calretinin over calbindin GABA neurons is reduced, and the neuronal migration capacity is decreased. Such phenotypes were replicated following transplantation of the DS GABAergic progenitors into the mouse medial septum. Gene expression profiling revealed altered cell migratory pathways, and correction of the PAK1 pathway mitigated the cell migration deficit in vitro. These results suggest that impaired migration of DS GABAergic neurons may contribute to the reduced number of interneurons in the cerebral cortex and hippocampus in DS patients. DS iPSC-derived GABA interneurons show cellular deficits DS GABA interneurons exhibit decreased migration in vitro and in vivo RNA-seq reveals that expression of PAK1 is disrupted in the DS interneurons Regulation of PAK1 pathway rescues the defects of migration
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Affiliation(s)
- Hai-Qin Huo
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China; Institute for Stem Cell and Neural Regeneration, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Zhuang-Yin Qu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China; Institute for Stem Cell and Neural Regeneration, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Fang Yuan
- Institute for Stem Cell and Neural Regeneration, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Lixiang Ma
- Department of Human Anatomy and Histology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Lin Yao
- Waisman Center, University of Wisconsin, Madison, WI 53705, USA
| | - Min Xu
- Institute for Stem Cell and Neural Regeneration, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Yao Hu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China; Institute for Stem Cell and Neural Regeneration, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Jing Ji
- Department of Neurosurgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Anita Bhattacharyya
- Waisman Center, University of Wisconsin, Madison, WI 53705, USA; Department of Cell and Regenerative Biology and Neuroscience University of Wisconsin, Madison, WI 53705, USA
| | - Su-Chun Zhang
- Waisman Center, University of Wisconsin, Madison, WI 53705, USA; Department of Cell and Regenerative Biology and Neuroscience University of Wisconsin, Madison, WI 53705, USA.
| | - Yan Liu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China; Institute for Stem Cell and Neural Regeneration, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China.
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Kim J, Choi IY, Duff KE, Lee P. Progressive Pathological Changes in Neurochemical Profile of the Hippocampus and Early Changes in the Olfactory Bulbs of Tau Transgenic Mice (rTg4510). Neurochem Res 2017; 42:1649-1660. [PMID: 28523532 DOI: 10.1007/s11064-017-2298-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Revised: 05/08/2017] [Accepted: 05/08/2017] [Indexed: 01/02/2023]
Abstract
Tauopathies such as Alzheimer's disease and frontotemporal lobe degeneration (FTLD-tau) dementia, characterized by pathologic aggregation of the microtubule-associated tau protein and formation of neurofibrillary tangles, have been linked to neurodegeneration and cognitive decline. The early detection of cerebral abnormalities and the identification of biological contributors to the continuous pathologic processes of neurodegeneration in tauopathies critically hinge on sensitive and reliable measures of biomarkers in the living brain. In this study, we measured alterations in a number of key neurochemicals associated with tauopathy-induced neurodegeneration in the hippocampus and the olfactory bulbs of a transgenic mouse model of FTLD-tauopathy, line rTg4510, using in vivo 1H magnetic resonance spectroscopy at 9.4 T. The rTg4510 line develops tauopathy at a young age (4-5 months), reaching a severe stage by 8-12 months of age. Longitudinal measurement of neurochemical concentrations in the hippocampus of mice from 5 to 12 months of age showed significant progressive changes with distinctive disease staging patterns including N-acetylaspartate, myo-inositol, γ-aminobutyric acid, glutathione and glutamine. The accompanying hippocampal volume loss measured using magnetic resonance imaging showed significant correlation (p < 0.01) with neurochemical measurements. Neurochemical alterations in the olfactory bulbs were more pronounced than those in the hippocampus in rTg4510 mice. These results demonstrate progressive neuropathology in the mouse model and provide potential biomarkers of early neuropathological events and effective noninvasive monitoring of the disease progression and treatment efficacy, which can be easily translated to clinical studies.
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Affiliation(s)
- Jieun Kim
- Hoglund Brain Imaging Center, University of Kansas Medical Center, 3901 Rainbow Blvd, Mail Stop 1052, Kansas City, KS, 66160, USA
| | - In-Young Choi
- Hoglund Brain Imaging Center, University of Kansas Medical Center, 3901 Rainbow Blvd, Mail Stop 1052, Kansas City, KS, 66160, USA.,Department of Neurology, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Karen E Duff
- Department of Integrative Neuroscience, Columbia University Medical Center, New York, NY, 10032, USA
| | - Phil Lee
- Hoglund Brain Imaging Center, University of Kansas Medical Center, 3901 Rainbow Blvd, Mail Stop 1052, Kansas City, KS, 66160, USA. .,Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, 66160, USA.
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Cecchini MP, Viviani D, Sandri M, Hähner A, Hummel T, Zancanaro C. Olfaction in People with Down Syndrome: A Comprehensive Assessment across Four Decades of Age. PLoS One 2016; 11:e0146486. [PMID: 26730728 PMCID: PMC4701393 DOI: 10.1371/journal.pone.0146486] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 12/17/2015] [Indexed: 11/26/2022] Open
Abstract
Background Down syndrome (DS) shows neuropathology similar to Alzheimer disease, which presents olfactory impairment. Previous work showed olfactory impairment in DS, but a comprehensive evaluation of olfactory function in DS is lacking. Methods We investigated a large number (n = 56; M = 31, F = 25) DS participants (age range18-57y) using the “Sniffin’ Sticks” Extended test. This comprises three subtests (threshold, discrimination, and identification) yielding a global score (TDI) defining normosmia, hyposmia, and functional anosmia. To the best of our knowledge, this is the second largest group of DS people investigated for olfactory function ever. Age- and sex matched euploid individuals (n = 53) were the control. Results In DS, TDI was lower (16.7±5.13 vs. 35.4±3.74; P<0.001), with DS people performing worse in any subtests (P<0.001 for all); 27 DS participants showed functional anosmia (i.e., TDI<16). In DS, age was weakly and negatively correlated with TDI (r = -0.28, P = 0.036) and identification (r = -0.34, P = 0.012). When participants were stratified in young adults (18-29y) and older adults (30-61y), a significant effect of age was found for identification in both DS (young adults, 8.3±2.58; older adults, 6.9±2.99; P = 0.031) and control (young-adult, 14.3±1.18, older adult, 13.0±1.54; P = 0.016). Conclusion Olfactory function is overall severely impaired in DS people and may be globally impaired at relatively young age, despite of reportedly normal smell. However, specificity of this olfactory profile to DS should be considered with some caution because cognition was not evaluated in all DS participants and comparison with a control group of non-DS individuals having cognitive disabilities was lacking. Further study is required to longitudinally assess olfactory dysfunction in DS and to correlate it with brain pathology.
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Affiliation(s)
- Maria Paola Cecchini
- Department of Neurological and Movement Sciences, Anatomy and Histology Section, University of Verona, Verona, Italy
- * E-mail:
| | - Dario Viviani
- U.O. Pediatria, Ospedale Sacro Cuore Don Calabria, Negrar, Italy
| | - Marco Sandri
- Department of Neurological and Movement Sciences, Anatomy and Histology Section, University of Verona, Verona, Italy
| | - Antje Hähner
- Smell & Taste Clinic, Department of Otorhinolaryngology, University of Dresden Medical School, Dresden, Germany
| | - Thomas Hummel
- Smell & Taste Clinic, Department of Otorhinolaryngology, University of Dresden Medical School, Dresden, Germany
| | - Carlo Zancanaro
- Department of Neurological and Movement Sciences, Anatomy and Histology Section, University of Verona, Verona, Italy
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Prandota J. Possible link between Toxoplasma gondii and the anosmia associated with neurodegenerative diseases. Am J Alzheimers Dis Other Demen 2014; 29:205-14. [PMID: 24413543 PMCID: PMC10852608 DOI: 10.1177/1533317513517049] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Toxoplasma gondii is an intracellular protozoan infecting 30% to 50% of global human population. Recently, it was suggested that chronic latent neuroinflammation caused by the parasite may be responsible for the development of several neurodegenerative diseases manifesting with the loss of smell. Studies in animals inoculated with the parasite revealed cysts in various regions of the brain, including olfactory bulb. Development of behavioral changes was paralleled by the preferential persistence of cysts in defined anatomic structures of the brain, depending on the host, strain of the parasite, its virulence, and route of inoculation. Olfactory dysfunction reported in Alzheimer's disease, multiple sclerosis, and schizophrenia was frequently associated with the significantly increased serum anti-T gondii immunoglobulin G antibody levels. Damage of the olfactory system may be also at least in part responsible for the development of depression because T gondii infection worsened mood in such patients, and the olfactory bulbectomized rat serves as a model of depression.
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Affiliation(s)
- Joseph Prandota
- Department of Social Pediatrics, Faculty of Health Sciences, Wroclaw Medical University, Wroclaw, Poland
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18
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Wang W, Tang Y, Ni L, Kim E, Jongwutiwes T, Hourvitz A, Zhang R, Xiong H, Liu HC, Rosenwaks Z. Overexpression of Uromodulin-like1 accelerates follicle depletion and subsequent ovarian degeneration. Cell Death Dis 2012. [PMID: 23190605 PMCID: PMC3542605 DOI: 10.1038/cddis.2012.169] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Murine Uromodulin-like 1 (Umodl1) encodes Ca2+-dependent EGF-like membrane-bound proteins. This study presents its novel expression in the immune and female reproductive systems. Upon stimulation by CD3/CD28 antibodies, Umodl1 showed a prompt and robust response in the proliferating CD4+ T cells, suggesting its implication in immune defense against pathogens. In ovary, Umodl1 is regulated by gonadotropins. Mice carrying extra copies of functional Umodl1 were generated by BAC transgenesis. Defects in the female reproductive system became evident from 4 months of age, manifested by reduced or diminished fertility. Histology revealed that the ovaries contained very few discernible follicles in the cortical region, and were devoid of distinguishable corpus lutea (CL). Among the multilayered preantral follicles, elevated apoptosis was observed in both the oocytes and surrounding granulosa cells (GCs). Furthermore, a high level of PPARγ indicated an abnormal adipogenesis in the mutant ovaries, which resulted in the conversion of GCs into adipocytes. By 6 months of age, all mutant mice became anovulatory. Ovarian tissues including CL, follicles of various stages and associated stromal cells were degenerated. Altered expression of AMH, follicle-stimulating hormone and other ovary-specific marker genes such as Gdf-9, Rnf35, NOHLH and Gcx-1 further demonstrated that the molecular properties of the mutant ovaries have been severely disturbed. This work presents a novel animal model for investigating the pathogenesis of premature ovarian failure or early ovarian ageing.
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Affiliation(s)
- W Wang
- The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Medical College of Cornell University, New York, NY 10065, USA.
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Cai Y, Xue ZQ, Zhang XM, Li MB, Wang H, Luo XG, Cai H, Yan XX. An age-related axon terminal pathology around the first olfactory relay that involves amyloidogenic protein overexpression without plaque formation. Neuroscience 2012; 215:160-73. [DOI: 10.1016/j.neuroscience.2012.04.043] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 04/14/2012] [Accepted: 04/18/2012] [Indexed: 01/08/2023]
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20
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Johns A, Homewood J, Stevenson R, Taylor A. Implicit and explicit olfactory memory in people with and without Down syndrome. RESEARCH IN DEVELOPMENTAL DISABILITIES 2012; 33:583-593. [PMID: 22138497 DOI: 10.1016/j.ridd.2011.11.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 10/27/2011] [Accepted: 11/02/2011] [Indexed: 05/31/2023]
Abstract
This study examined differences in implicit and explicit memory performance between people with Down syndrome (DS), their siblings, children matched on mental age, and university undergraduates, using olfactory stimuli. The DS and mental-age matched participants were also compared on two tasks of executive function. The data revealed implicit memory for olfactory stimuli. Further, people with DS performed similarly to each control group on the implicit memory task, but performed significantly poorer than all control groups on the explicit memory task. Impairment to executive functioning was identified as a possible cause of this deficit in explicit memory as people with DS performed more poorly than the mental-age matched controls on both tasks of executive function.
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Affiliation(s)
- Adam Johns
- Department of Psychology, Macquarie University, Sydney, NSW 2109, Australia.
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21
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Simoes de Souza FM, Busquet N, Blatner M, Maclean KN, Restrepo D. Galantamine improves olfactory learning in the Ts65Dn mouse model of Down syndrome. Sci Rep 2011; 1:137. [PMID: 22355654 PMCID: PMC3216618 DOI: 10.1038/srep00137] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 09/28/2011] [Indexed: 11/20/2022] Open
Abstract
Down syndrome (DS) is the most common form of congenital intellectual disability. Although DS involves multiple disturbances in various tissues, there is little doubt that in terms of quality of life cognitive impairment is the most serious facet and there is no effective treatment for this aspect of the syndrome. The Ts65Dn mouse model of DS recapitulates multiple aspects of DS including cognitive impairment. Here the Ts65Dn mouse model of DS was evaluated in an associative learning paradigm based on olfactory cues. In contrast to disomic controls, trisomic mice exhibited significant deficits in olfactory learning. Treatment of trisomic mice with the acetylcholinesterase inhibitor galantamine resulted in a significant improvement in olfactory learning. Collectively, our study indicates that olfactory learning can be a sensitive tool for evaluating deficits in associative learning in mouse models of DS and that galantamine has therapeutic potential for improving cognitive abilities.
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Affiliation(s)
- Fabio M. Simoes de Souza
- Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A.
- These authors contributed equally to this work
| | - Nicolas Busquet
- Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A.
- Department of Pediatrics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A
- These authors contributed equally to this work
| | | | - Kenneth N. Maclean
- Department of Pediatrics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A
| | - Diego Restrepo
- Cell and Developmental Biology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, U.S.A.
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22
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Silveira-Moriyama L, Hughes G, Church A, Ayling H, Williams DR, Petrie A, Holton J, Revesz T, Kingsbury A, Morris HR, Burn DJ, Lees AJ. Hyposmia in progressive supranuclear palsy. Mov Disord 2010; 25:570-7. [PMID: 20209627 DOI: 10.1002/mds.22688] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Previous studies suggested that olfaction is normal in progressive supranuclear palsy (PSP). We applied the University of Pennsylvania Smell Identification Test (UPSIT) to 36 patients with PSP who scored more than 18 on the Mini Mental State Examination (MMSE), 140 patients with nondemented Parkinson's disease (PD) and 126 controls. Mean UPSIT scores in PSP were lower than in controls (P < 0.001) but higher than in PD (P < 0.001) after adjusting for age, gender, and smoking history. For patients with PSP, UPSIT scores correlated with MMSE (r = 0.44, P = 0.006) but not disease duration (P = 0.6), motor subscale of the Unified Parkinson's Disease Rating Scale (P = 0.2), or Frontal Assessment Battery (P = 0.5). The brains of six of the patients with PSP were examined postmortem and all revealed neurofibrillary tangles and tau accumulation in the rhinencephalon, although only three had hyposmia. Further prospective studies including patients with early PSP and PSP-P with postmortem confirmation might help clarify if smell tests could be useful when the differential diagnosis lies between PD and PSP.
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Affiliation(s)
- Laura Silveira-Moriyama
- Reta Lila Weston Institute of Neurological Studies, UCL Institute of Neurology, London, United Kingdom
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A possible pathogenesis for Alzheimer’s disease: Craniomaxillofacial dysfunction leading to localized cerebrospinal fluid stasis. Med Hypotheses 2009; 72:199-210. [DOI: 10.1016/j.mehy.2008.09.044] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Revised: 09/08/2008] [Accepted: 09/26/2008] [Indexed: 11/20/2022]
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Dulay MF, Gesteland RC, Shear PK, Ritchey PN, Frank RA. Assessment of the influence of cognition and cognitive processing speed on three tests of olfaction. J Clin Exp Neuropsychol 2007; 30:327-37. [PMID: 17852612 DOI: 10.1080/13803390701415892] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The extent to which measures of working memory, cognitive speed, and verbal retrieval are associated with performance on tests of olfaction was evaluated in a sample of 138 older adults. Structural equation modeling techniques indicated that verbal retrieval difficulties significantly affect performance on the University of Pennsylvania Smell Identification Test (UPSIT). Further, poor working memory and slow cognitive speed significantly affect performance on the UPSIT and the phenyl ethyl alcohol threshold test. The Sniff Magnitude Test was not influenced by any of the cognitive variables. Odor threshold and identification tasks may overestimate olfactory loss when cognitive impairment is not taken into account.
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Affiliation(s)
- Mario F Dulay
- Department of Neurosurgery, Baylor College of Medicine, 6560 Fannin, NB330, Houston, TX 77030, USA.
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25
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Mazur-Kolecka B, Frackowiak J. Neprilysin protects human neuronal progenitor cells against impaired development caused by amyloid-β peptide. Brain Res 2006; 1124:10-8. [PMID: 17112488 DOI: 10.1016/j.brainres.2006.09.064] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2006] [Revised: 09/12/2006] [Accepted: 09/18/2006] [Indexed: 10/23/2022]
Abstract
Transplantation of human neuronal progenitor cells (HNPC) is being considered for neuroreplacement therapy in beta-amyloidosis associated with neuronal loss in Down's syndrome and Alzheimer's disease. However, the influence of amyloid-beta-containing brain environment on the development of HNPCs is unknown. Recently, we demonstrated that amyloid-beta peptide (Abeta) impaired differentiation of HNPCs in culture through oxidative stress. Now we studied the effect of neprilysin, an Abeta-degrading enzyme, on development of neuronal colonies from neurospheres of HNPCs in the presence of Abeta1-40. Neprilysin increased the number of neurospheres that formed colonies of neuron-like cells. This effect of neprilysin was associated with reduced amounts of the monomeric and dimeric Abeta that remained in culture supernatants as well as the Abeta uptaken by differentiating HNPCs. Phosphoramidon, a neprilysin inhibitor, attenuated these effects of neprilysin. In control cultures of HNPCs that grew without exogenous Abeta1-40, the treatment with neprilysin reduced the number of developing colonies. This effect might result from degradation by neprilysin of endogenous Abeta produced and secreted by HNPCs or other peptides that are involved in neuronal development. The results demonstrate that even a partial reduction of extracellular Abeta levels by neprilysin may facilitate development of HNPCs into neurons in an environment overloaded with Abeta. This finding suggests that neprilysin could facilitate neuroreplacement therapy with HNPCs in treatment of neurodegenerative diseases.
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Affiliation(s)
- Bozena Mazur-Kolecka
- Department of Developmental Neurobiology, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY 10314, USA.
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26
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Chen MA, Lander TR, Murphy C. Nasal health in Down syndrome: a cross-sectional study. Otolaryngol Head Neck Surg 2006; 134:741-5. [PMID: 16647527 DOI: 10.1016/j.otohns.2005.12.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Accepted: 12/29/2005] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To investigate peripheral nasal pathology as a contributor to olfactory impairment in DS. STUDY DESIGN Twenty DS and 16 non-DS subjects were recruited. Nasal history and symptoms were assessed by self-report or informant. Olfactory threshold, odor identification, and nasal endoscopy were assessed on each subject. RESULTS DS subjects were impaired on olfactory threshold (P<0.0001) and odor identification (P<0.001). Although DS subjects tended toward upper-respiratory infections, sleep-disordered breathing, and nasal itching, differences were not significant (P=0.07, 0.06, and 0.058, respectively). There were no significant differences on self-reported nasal history or symptoms. Endoscopy showed equivalent health in DS and control subjects. CONCLUSION This DS population shows olfactory impairment. However, nasal health is comparable in DS subjects and controls. Nasal dysfunction is unlikely to contribute to olfactory impairment in DS. SIGNIFICANCE Olfactory deficits in DS appear to be secondary to central, rather than rhinologic, pathology. EBM RATING B-2b.
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Affiliation(s)
- Margaret A Chen
- Division of Head and Neck Surgery, University of California, San Diego Medical Center, San Diego, California 92120, USA
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27
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Corcoran C, Whitaker A, Coleman E, Fried J, Feldman J, Goudsmit N, Malaspina D. Olfactory deficits, cognition and negative symptoms in early onset psychosis. Schizophr Res 2005; 80:283-93. [PMID: 16125904 PMCID: PMC3886553 DOI: 10.1016/j.schres.2005.07.028] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Revised: 07/06/2005] [Accepted: 07/07/2005] [Indexed: 01/16/2023]
Abstract
BACKGROUND Smell identification deficits (SID) are common in adult schizophrenia, where they are associated with negative symptoms and lower intelligence. However, smell identification has not been examined in adolescents with early onset psychosis, wherein diagnosis is often obscure, and there are few prognostic predictors. METHOD We examined smell identification, diagnosis, neuropsychological performance and symptoms in 26 well characterized adolescents with early onset psychosis, age 11-17 years. RESULTS SID existed in the sample and were more common in patients with schizophrenia and psychotic depression than in patients with psychosis NOS and bipolar disorder. As in adults, SID were significantly associated with greater negative symptoms and lower verbal IQ. However, the associations of verbal IQ (and other verbal tasks) to smell identification in this pediatric sample were explained by the relation of both of these types of variables to negative symptoms. CONCLUSIONS SID existed across this sample of youths with psychotic disorder, and were specifically related to typical characteristics of schizophrenia, such as negative symptoms and lower intelligence, but not to features of bipolar disorder, such as grandiosity. SID is a characteristic of early onset psychosis that may be useful for prognostic purposes.
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Affiliation(s)
- Cheryl Corcoran
- Corresponding author. Tel.: +1 212 543 6177; fax: +1 212 543 6176
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28
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Di Schiavi E, Riano E, Heye B, Bazzicalupo P, Rugarli EI. UMODL1/Olfactorin is an extracellular membrane-bound molecule with a restricted spatial expression in olfactory and vomeronasal neurons. Eur J Neurosci 2005; 21:3291-300. [PMID: 16026467 DOI: 10.1111/j.1460-9568.2005.04164.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The olfactory system provides a unique model for developmental neurobiology. Precise targeting of axonal projections from sensory neurons located in the olfactory epithelium to specific neurons in the olfactory bulb establishes a highly refined spatial sensory map. Distinctively, this process is not restricted to embryonic stages, but continues during the entire life of mammals. A number of secreted and membrane molecules have been implicated in guidance and targeting of olfactory sensory neurons. Here we describe olfactorin, the protein product of the mouse Umodl1 gene, as a potential new element in this process. Olfactorin is a secreted modular protein containing several domains typically present in extracellular matrix proteins (EMI, WAP, FNIII, Ca2+ -binding EGF-like, SEA and ZP domains). By in situ hybridization we find that during embryonic development expression of the Umodl1 gene is detectable only in the olfactory epithelium and vomeronasal organ starting at embryonic day 16.5. At this stage, Umodl1 expression within the olfactory epithelium is punctate, and is restricted to only some of the sensory neurons. At birth and postnatally, expression in these organs continues and involves more neurons. Kallmann syndrome is a genetic disease in which olfactory axons fail to connect to target neurons in the bulb. We tested whether olfactorin might be responsible for an autosomal form of this disease and show that this is not the case. However, based on its domain composition and on the expression in olfactory neurons we suggest that olfactorin may play a role in correct olfactory axon navigation to the brain.
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Affiliation(s)
- Elia Di Schiavi
- Institute of Genetics and Biophysics-A. Buzzati Traverso, IGB-ABT, via P. Castellino 111, CNR, 80131 Naples, Italy
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Mazur-Kolecka B, Golabek A, Nowicki K, Flory M, Frackowiak J. Amyloid-beta impairs development of neuronal progenitor cells by oxidative mechanisms. Neurobiol Aging 2005; 27:1181-92. [PMID: 16105709 DOI: 10.1016/j.neurobiolaging.2005.07.006] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2005] [Revised: 06/23/2005] [Accepted: 07/10/2005] [Indexed: 01/05/2023]
Abstract
Neuronal progenitor cells (NPCs) are being considered for treatment of neurodegenerative diseases associated with beta-amyloidosis: Alzheimer's disease (AD) and Down syndrome (DS). However, the neurotoxic properties of amyloid-beta peptide (Abeta) may impair survival and differentiation of transplanted NPCs. Hence, we studied the influence of Abeta on development of human NPCs--proliferation, migration, formation of colonies of neurons, formation processes--in culture. Pre-fibrillized human Abeta1-40 blocked development of neuronal colonies. NPC development was impaired in the presence of soluble Abeta1-40 (1.75-7 microM), and NPC differentiation into large and small neurons was altered, as demonstrated by morphometry. Antioxidant vitamin E partially abolished these effects, but not the reduced formation of neuronal processes. NPCs cultured with 7 microM Abeta1-40 accumulated Abeta monomers and oligomers and contained higher levels of protein carbonyls and lipid peroxidation products HNE and MDA. We suggest that Abeta1-40 impairs development of NPCs by oxidative damage. Hence, a prerequisite of successful neuroreplacement therapy using NPCs in AD and DS/AD may be removal of amyloid-beta and antioxidative treatment.
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Affiliation(s)
- B Mazur-Kolecka
- Department of Developmental Neurobiology, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY 10314, USA.
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Özdener MH, Rawson NE. OLFACTORY DYSFUNCTION IN NEURODEGENERATIVE DISEASES. ELECTRONIC JOURNAL OF GENERAL MEDICINE 2004. [DOI: 10.29333/ejgm/82202] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Zucco GM, Ingegneri G. Olfactory deficits in HIV-infected patients with and without AIDS dementia complex. Physiol Behav 2004; 80:669-74. [PMID: 14984801 DOI: 10.1016/j.physbeh.2003.12.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2003] [Revised: 09/01/2003] [Accepted: 12/01/2003] [Indexed: 11/28/2022]
Abstract
The aim of the present study was to examine the effect of HIV infection on odour memory. Recognition and identification olfactory tests were administered to six groups of patients defined according to a decrease in cellular immunity: asymptomatic HIV seropositive (HIV+), symptomatic HIV+, HIV+ AIDS, and three groups with a mild, moderate, and severe degree of dementia (AIDS dementia complex [ADC]). Consistent with the literature, the general results show that HIV infection is associated with a decrease in olfactory ability. In addition, a polynomial linear trend analysis indicates a constant decrease in performance from the first to the sixth group of patients, related to the number of CD4 T lymphocytes circulating and to the severity of the pathology. An interesting result regards the drop in performance exhibited by ADC patients on the identification task. Reasonably, such an effect is not attributable to a decline in olfactory ability only, bit rather to a severe semantic memory deficit. It follows that the two tasks used here can be useful clinical supports to discriminate between the mental operations involved in a low cognitive demand task (recognition) and in a high cognitive demand task (identification).
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Affiliation(s)
- Gesualdo M Zucco
- Department of General Psychology, University of Padua, Padua, Italy.
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Abstract
Recent research on the olfactory event-related potential (OERP) using inter-stimulus intervals (ISIs) of 90 s and shorter has revealed a marked decrease in component amplitude after the first trial, with a leveling off for the remaining trials. Studies manipulating the ISI in olfactory and other modalities demonstrate an association between higher amplitudes and longer ISIs, suggesting that habituation occurs at short time intervals between each stimulus presentation. The present study attempted to reduce the effects of habituation by using a 10-min ISI and fewer trials. OERPs were recorded monopolarly at the Fz, Cz and Pz electrode sites in ten subjects (five males, five females), for three trials using a 10-min ISI. Results demonstrated no significant reduction in component amplitudes across trials and no significant difference in latencies over trials, indicating no habituation effect at this ISI. These results indicate that with a 10-min ISI and three trial recordings, a complete reduction in habituation can be achieved. These findings may prove to be clinically useful to physicians who can implement this technique to assess olfactory functioning in cognitively impaired individuals or to assess malingering.
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Affiliation(s)
- Spencer Wetter
- SDSU/UCSD Joint Doctoral Program in Clinical Psychology, 6363 Alvarado Ct. Suite 101, San Diego, CA, 92120-4913, USA
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Sugaya K. Potential use of stem cells in neuroreplacement therapies for neurodegenerative diseases. INTERNATIONAL REVIEW OF CYTOLOGY 2003; 228:1-30. [PMID: 14667041 DOI: 10.1016/s0074-7696(03)28001-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The use of stem cells for neuroreplacement therapy is no longer science fiction--it is science fact. We have succeeded in the development of neural and mesenchymal stem cell transplantation to produce neural cells in the brain. We have also seen improvement in cognitive function following stem cell transplantation in a memory-impaired aged animal model. These results promise a bright future for stem cell therapies in neurodegenerative diseases. Before we begin to think about clinical applications beyond the present preclinical studies, we have to consider the pathophysiological environment of individual diseases and weigh the factors that affect stem cell biology. Here, I not only review potential therapeutic applications of stem cell strategies in neurodegenerative diseases, but also discuss stem cell biology regarding factors that are altered under disease conditions.
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Affiliation(s)
- Kiminobu Sugaya
- Department of Psychiatry, University of Illinois at Chicago, The Psychiatric Institute, Chicago, Illinois 60612, USA
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Di Rienzo L, Artuso A, Colosimo C. Isolated congenital agenesis of the olfactory bulbs and tracts in a child without Kallmann's syndrome. Ann Otol Rhinol Laryngol 2002; 111:657-60. [PMID: 12126024 DOI: 10.1177/000348940211100715] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Lino Di Rienzo
- Otolaryngology Department, San Filippo Neri Hospital, Rome, Italy
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Murphy C. Olfactory functional testing: sensitivity and specificity for Alzheimer's disease. Drug Dev Res 2002. [DOI: 10.1002/ddr.10067] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Nijjar RK, Murphy C. Olfactory impairment increases as a function of age in persons with Down syndrome. Neurobiol Aging 2002; 23:65-73. [PMID: 11755021 DOI: 10.1016/s0197-4580(01)00263-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Neuropathology similar to that found in the brains of patients with Alzheimer's disease (AD) has consistently been observed in older individuals with Down syndrome (DS) and this neuropathology is particularly prevalent in areas involved in olfaction. The present study investigated the effects of age on the expression of olfactory impairment in Down syndrome to address the hypothesis that older adults with DS show greater deficits in olfactory function compared with younger persons with DS and compared with age and IQ matched control groups. Between group differences showed that persons with DS had significant deficits in olfactory functioning compared to the two control groups. Further, within the DS group, older adults performed more poorly than the young adults or children. Results support the hypothesis that in a group of persons at risk for AD because of DS, olfactory impairment is greater in older individuals, suggesting progressive impairment over time. Deficits in olfactory function may be useful in signalling incipient dementia in DS.
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Affiliation(s)
- Rani K Nijjar
- Department of Psychology, San Diego State University, San Diego, CA, USA
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37
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Kulnane LS, Lamb BT. Neuropathological characterization of mutant amyloid precursor protein yeast artificial chromosome transgenic mice. Neurobiol Dis 2001; 8:982-92. [PMID: 11741394 DOI: 10.1006/nbdi.2001.0446] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mutations in the amyloid precursor protein (APP) gene result in elevated production and deposition of the 42 amino acid beta-amyloid (Abeta1-42) peptide and early-onset Alzheimer's disease (AD). To accurately examine the effect of the APP FAD mutations in vivo, we introduced yeast artificial chromosomes (YACs) containing the entire genomic copy of human APP harboring FAD mutations into transgenic mice. Our current results demonstrate that mutant APP YAC transgenic mice exhibit many features characteristic of human AD, including regional deposition of Abeta with preferential deposition of Abeta1-42, extensive neuritic abnormalities as evidenced by staining with APP, ubiquitin, neurofilament, and hyperphosphorylated tau antibodies, increased markers of inflammation, and the overlapping deposition of Abeta with apolipoproteins E and J. Our results also suggest that APP YAC transgenic mice possess unique pathological attributes when compared to other transgenic mouse models of AD that may reflect the experimental design of each model.
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Affiliation(s)
- L S Kulnane
- Department of Genetics and Neuroscience, Case Western Reserve University and Center for Human Genetics, Cleveland, Ohio 44106, USA
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38
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Sugaya K, Brannen CL. Stem cell strategies for neuroreplacement therapy in Alzheimer's disease. Med Hypotheses 2001; 57:697-700. [PMID: 11918428 DOI: 10.1054/mehy.2001.1424] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The existence of neural stem cells (NSCs) in the adult human brain provides impetus for investigating possible neuroreplacement therapies for neurodegenerative disease. Due to recent advances in techniques affording isolation and maintenance of NSCs using non-serum culture media, these cells have become exciting candidates for therapeutic strategies. We are able to expand NSCs by mitogenic growth factors in vitro and in defined conditions, NSCs differentiate into each of the diverse brain cell types: neurons, astrocytes and oligodendrocytes. This article addresses the involvement of amyloid-beta precursor protein and the presenilins in NSCs' biology and possible application of NSCs for therapeutic approaches in Alzheimer's disease. Ongoing studies in our laboratory, and recent findings by others using human neural progenitors, serve as the conceptual frame for this article.
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Affiliation(s)
- K Sugaya
- The Psychiatric Institute, Department of Psychiatry, The University of Illinois at Chicago, 60612, USA.
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Abstract
The sense of smell has been largely ignored by otorhinolaryngologists, even though 1) its medical stewardship falls within their specialty's purview, 2) olfactory dysfunction is not uncommon in the general population, and 3) disorders of olfaction have significant quality of life, nutritional, and safety consequences. This report provides a succinct overview of the major intranasal neural systems present in humans (namely, cranial nerves O, I, and V, and the nonfunctional accessory [vomeronasal] organ system), along with a summary of notable findings resulting from the application of modern olfactory tests to patient populations, emphasizing diseases of the nose. Such tests have led to the discovery of significant influences of age, gender, smoking, toxic exposure, and genetics on the ability to smell. Within the field of otorhinolaryngology, they have revealed that 1) surgical and medical interventions in patients with rhinosinusitis do not, on average, lead to complete recovery of olfactory function, despite common beliefs to the contrary, and 2) associations are generally lacking between measures of airway patency and olfactory function in such cases. These findings have thrown into question the dogma that olfactory loss in rhinosinusitis is attributable primarily to blockage of airflow to the receptors and have led to histopathological studies demonstrating significant olfactory epithelial compromise in sinonasal syndromes.
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Affiliation(s)
- R L Doty
- Smell and Taste Center, Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania Medical Center, 5 Ravdin Building, 3400 Spruce St., Philadelphia, PA 19104, USA
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Wetter S, Murphy C. Individuals with Down's syndrome demonstrate abnormal olfactory event-related potentials. Clin Neurophysiol 1999; 110:1563-9. [PMID: 10479023 DOI: 10.1016/s1388-2457(99)00086-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE Recent research has demonstrated that individuals with Down's syndrome (DS) develop plaques and tangles in the brain similar to people with Alzheimer's disease. As a result, they show increased dementia and decreased olfactory functioning compared to healthy individuals. The olfactory event-related potential (OERP) has been used as an objective quantitative measure of olfactory functioning in normal and clinical populations. The present study investigated the utility of the latency and amplitude of the OERP components in examining olfactory dysfunction in DS individuals. METHODS OERPs were recorded monopolarly at the Fz, Cz and Pz electrode sites, using amyl acetate at a 60 s inter-stimulus interval, from individuals with DS (mean age 26.0 years) and age-matched normal controls. Participants were screened for nasal health and odor thresholds were assessed. Dementia was assessed using the dementia rating scale (DRS). RESULTS Results indicate that DS subjects have significantly longer latencies in the sensory (N1, P2, and N2) and cognitive (P3) components of the OERP than normal controls. Odor threshold was significantly associated with sensory OERP components. In addition, DS subjects with a higher level of dementia showed significantly longer P3 latencies than those with lower dementia levels. CONCLUSIONS The study suggests that the OERP may be a useful measure of olfactory dysfunction in DS which may precede developing dementia in this population.
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Affiliation(s)
- S Wetter
- Department of Psychology, San Diego State University, CA 92120-4913, USA
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Covington JW, Geisler MW, Polich J, Murphy C. Normal aging and odor intensity effects on the olfactory event-related potential. Int J Psychophysiol 1999; 32:205-14. [PMID: 10437632 DOI: 10.1016/s0167-8760(99)00012-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Olfactory event-related potentials (OERPs) were recorded in 14 young and 14 older adults, with odor strength of isoamyl acetate manipulated to assess olfactory stimulus intensity. Young participants produced significantly larger N1/P2, N2/P3 amplitudes and shorter N1, P2 and N2 latencies than older participants. Medium- and high-odor concentrations elicited significantly shorter P2 and N2 latencies than the lowest concentration for both age groups. Odor concentration appears to affect the speed of olfactory stimulus information processing regardless of age.
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Affiliation(s)
- J W Covington
- Department of Psychology, San Diego State University, CA 92120-4913, USA
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Abstract
Alzheimer's (AD) patients show neuropathological changes in areas of the brain central to olfactory processing, suggesting the theoretical importance and potential diagnostic utility of investigating functional changes in olfaction in these patients. Persons with Down's Syndrome who live to the fourth decade develop neuropathological changes in the brain similar to those found in AD. A series of investigations have been conducted to assess olfaction function in both patients with Alzheimer's disease and persons with Down's Syndrome. Functional testing included olfactory threshold, odor identification, odor similarity judgements, odor recognition memory, odor recall, odor fluency. Both Alzheimer's patients and persons with Down's Syndrome showed significant impairment in olfactory function, with some measures showing more impairment than others in the early stages of the disease process. Longitudinal investigation of several of the measures indicated decreased function over time consonant with falling DRS scores. Normal controls who tested positive for the APOE4 allele showed impaired odor identification compared to those who were allele negative. Patients with Huntington's Disease showed olfactory functional impairments, although the degree of impairment differed from the cortical dementias for some of these tasks. The sensitivity and specificity of these assessments will be discussed in relation to analogous assessments in other sensory modalities.
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Affiliation(s)
- C Murphy
- University of California-San Diego, SDSU-UCSD Joint Doctoral Program in Clinical Psychology, 92120, USA.
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