1
|
Lee DH, Song J. Impaired olfactory system in metabolic imbalance-related neuropathology. Life Sci 2024:122967. [PMID: 39142504 DOI: 10.1016/j.lfs.2024.122967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2024] [Revised: 07/25/2024] [Accepted: 08/10/2024] [Indexed: 08/16/2024]
Abstract
Olfactory dysfunction, influenced by factors such as aging and environmental stress, is linked to various neurological disorders. The olfactory bulb's connections to brain areas like the hypothalamus, piriform cortex, entorhinal cortex, and limbic system make olfactory dysfunction a contributor to a range of neuropathological conditions. Recent research has underscored that olfactory deficits are prevalent in individuals with both metabolic syndrome and dementia. These systemic metabolic alterations correlate with olfactory impairments, potentially affecting brain regions associated with the olfactory bulb. In cases of metabolic syndrome, phenomena such as insulin resistance and disrupted glucose metabolism may result in compromised olfactory function, leading to multiple neurological issues. This review synthesizes key findings on the interplay between metabolic-induced olfactory dysfunction and neuropathology. It emphasizes the critical role of olfactory assessment in diagnosing and managing neurological diseases related to metabolic syndrome.
Collapse
Affiliation(s)
- Dong Hoon Lee
- Department of Otolaryngology-Head and Neck Surgery, Chonnam National University Medical School & Hwasun Hospital, Hwasun 58128, Republic of Korea.
| | - Juhyun Song
- Department of Anatomy, Chonnam National University Medical School, Hwasun 58128, Republic of Korea.
| |
Collapse
|
2
|
Chen Y, Ren P, He X, Yan F, Gu R, Bai J, Zhang X. Olfactory bulb neurogenesis depending on signaling in the subventricular zone. Cereb Cortex 2023; 33:11102-11111. [PMID: 37746807 DOI: 10.1093/cercor/bhad349] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 09/04/2023] [Accepted: 09/06/2023] [Indexed: 09/26/2023] Open
Abstract
Olfaction is a crucial sense that is essential for the well-being and survival of individuals. Olfactory bulb (OB) is the first olfactory relay station, and its function depends on newly generated neurons from the subventricular zone (SVZ). These newly born neurons constantly migrate through the rostral migratory stream to integrate into existing neural networks within the OB, thereby contributing to olfactory information processing. However, the mechanisms underlying the contribution of SVZ adult neurogenesis to OB neurogenesis remain largely elusive. Adult neurogenesis is a finely regulated multistep process involving the proliferation of adult neural stem cells (aNSCs) and neural precursor cells, as well as the migration and differentiation of neuroblasts, and integration of newly generated neurons into preexisting neuronal circuitries. Recently, extensive studies have explored the mechanism of SVZ and OB neurogenesis. This review focused on elucidating various molecules and signaling pathways associated with OB neurogenesis dependent on the SVZ function. A better understanding of the mechanisms underlying the OB neurogenesis on the adult brain is an attractive prospect to induce aNSCs in SVZ to generate new neurons to ameliorate olfactory dysfunction that is involved in various diseases. It will also contribute to developing new strategies for the human aNSCs-based therapies.
Collapse
Affiliation(s)
- Yali Chen
- Laboratory of Molecular Neurobiology, Medical Faculty, Kunming University of Science and Technology, Kunming 650500, China
| | - Peng Ren
- Laboratory of Molecular Neurobiology, Medical Faculty, Kunming University of Science and Technology, Kunming 650500, China
| | - Xiongjie He
- Laboratory of Molecular Neurobiology, Medical Faculty, Kunming University of Science and Technology, Kunming 650500, China
| | - Fang Yan
- Laboratory of Molecular Neurobiology, Medical Faculty, Kunming University of Science and Technology, Kunming 650500, China
| | - Rou Gu
- Laboratory of Molecular Neurobiology, Medical Faculty, Kunming University of Science and Technology, Kunming 650500, China
| | - Jie Bai
- Laboratory of Molecular Neurobiology, Medical Faculty, Kunming University of Science and Technology, Kunming 650500, China
| | - Xianwen Zhang
- Laboratory of Molecular Neurobiology, Medical Faculty, Kunming University of Science and Technology, Kunming 650500, China
| |
Collapse
|
3
|
Yang J, Yang N, Zhao H, Qiao Y, Li Y, Wang C, Lim KL, Zhang C, Yang W, Lu L. Adipose transplantation improves olfactory function and neurogenesis via PKCα-involved lipid metabolism in Seipin Knockout mice. Stem Cell Res Ther 2023; 14:239. [PMID: 37674230 PMCID: PMC10483743 DOI: 10.1186/s13287-023-03463-9] [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: 08/12/2022] [Accepted: 08/22/2023] [Indexed: 09/08/2023] Open
Abstract
BACKGROUND Lipodystrophy-associated metabolic disorders caused by Seipin deficiency lead to not only severe lipodystrophy but also neurological disorders. However, the underlying mechanism of Seipin deficiency-induced neuropathy is not well elucidated, and the possible restorative strategy needs to be explored. METHODS In the present study, we used Seipin knockout (KO) mice, combined with transcriptome analysis, mass spectrometry imaging, neurobehavior test, and cellular and molecular assay to investigate the systemic lipid metabolic abnormalities in lipodystrophic mice model and their effects on adult neurogenesis in the subventricular zone (SVZ) and olfactory function. After subcutaneous adipose tissue (AT) transplantation, metabolic and neurological function was measured in Seipin KO mice to clarify whether restoring lipid metabolic homeostasis would improve neurobehavior. RESULTS It was found that Seipin KO mice presented the ectopic accumulation of lipids in the lateral ventricle, accompanied by decreased neurogenesis in adult SVZ, diminished new neuron formation in the olfactory bulb, and impaired olfactory-related memory. Transcriptome analysis showed that the differentially expressed genes (DEGs) in SVZ of adult Seipin KO mice were significantly enriched in lipid metabolism. Mass spectrometry imaging showed that the levels of glycerophospholipid and diglyceride (DG) were significantly increased. Furthermore, we found that AT transplantation rescued the abnormality of peripheral metabolism in Seipin KO mice and ameliorated the ectopic lipid accumulation, concomitant with restoration of the SVZ neurogenesis and olfactory function. Mechanistically, PKCα expression was up-regulated in SVZ tissues of Seipin KO mice, which may be a potential mediator between lipid dysregulation and neurological disorder. DG analogue (Dic8) can up-regulate PKCα and inhibit the proliferation and differentiation of neural stem cells (NSCs) in vitro, while PKCα inhibitor can block this effect. CONCLUSION This study demonstrates that Seipin deficiency can lead to systemic lipid disorder with concomitant SVZ neurogenesis and impaired olfactory memory. However, AT restores lipid homeostasis and neurogenesis. PKCα is a key mediator mediating Seipin KO-induced abnormal lipid metabolism and impaired neurogenesis in the SVZ, and inhibition of PKCα can restore the impaired neurogenesis. This work reveals the underlying mechanism of Seipin deficiency-induced neurological dysfunction and provides new ideas for the treatment of neurological dysfunction caused by metabolic disorders.
Collapse
Affiliation(s)
- Jing Yang
- Department of Anatomy, Shanxi Medical University, Taiyuan, 030001, People's Republic of China
| | - Na Yang
- Department of Anatomy, Shanxi Medical University, Taiyuan, 030001, People's Republic of China
| | - Huifang Zhao
- School of Basic Medical Sciences, Shanxi Medical University, Taiyuan, 030001, People's Republic of China
| | - Yan Qiao
- Analytical Instrumentation Center and State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, People's Republic of China
| | - Yanqiu Li
- Analytical Instrumentation Center and State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, People's Republic of China
| | - Chunfang Wang
- Laboratory Animal Research Center of Shanxi Medical University, Shanxi Key Laboratory of Animal and Animal Model of Human Diseases, Shanxi Medical University, Taiyuan, People's Republic of China
| | - Kah-Leong Lim
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Chengwu Zhang
- School of Basic Medical Sciences, Shanxi Medical University, Taiyuan, 030001, People's Republic of China.
| | - Wulin Yang
- Anhui Province Key Laboratory of Medical Physics and Technology, Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, People's Republic of China.
- Cancer Hospital, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, People's Republic of China.
| | - Li Lu
- Department of Anatomy, Shanxi Medical University, Taiyuan, 030001, People's Republic of China.
- Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, People's Republic of China.
| |
Collapse
|
4
|
Chen HC, Ma YZ, Cao JX, Zhang YS, Zhang L, Gao LP, Jing YH. Synergistic effects of hIAPP and Aβ 1-42 impaired the olfactory function associated with the decline of adult neurogenesis in SVZ. Neuropeptides 2022; 96:102268. [PMID: 35841876 DOI: 10.1016/j.npep.2022.102268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 06/22/2022] [Accepted: 06/26/2022] [Indexed: 10/17/2022]
Abstract
According to many in the field,the prevalence of Alzheimer's disease (AD) in type II diabetes (T2DM) populations is considerably higher than that in the normal population. Human islet amyloid polypeptide (hIAPP) is considered to be a common risk factor for T2DM and AD. Preliminary observations around T2DM animal model show that the decrease of adult neural stem cells (NSCs) in the subventricular zone (SVZ) is accompanied by olfactory dysfunction. Furthermore, impaired olfactory function could serve as to an early predictor of neurodegeneration,which is associated with cognitive impairment. However, the synergistic effects between hIAPP and amyloid-beta (Aβ) 1-42 in the brain and the neurodegeneration remains to be further clarified. In this study, olfactory capacity, synaptic density, status of NSC in SVZ, and status of newborn neurons in olfactory bulb (OB) were assessed 6 months after stereotactic injection of oligomer Aβ1-42 into the dens gyrus (DG) of hIAPP-/+ mice or wild-type homogenous mice. Our results set out that Aβ42 and amylin co-localized into OB and raised Aβ42 deposition in hIAPP-/+ mice compared with wild-type brood mice. In addition, 6 months after injection of Aβ1-42 in hIAPP-/+ mice, these mice showed increased olfactory dysfunction, significant loss of synapses, depletion of NSC in SVZ, and impaired cell renewal in OB. Our present study suggested that the synergistic effects between hIAPP and Aβ1-42 impairs olfactory function and was associated with decreased neurogenesis in adults with SVZ.
Collapse
Affiliation(s)
- Hai-Chao Chen
- Institute of Anatomy and Histology & Embryology, Neuroscience, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Yue-Zhang Ma
- Institute of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Jia-Xin Cao
- Institute of Anatomy and Histology & Embryology, Neuroscience, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Yi-Shu Zhang
- Institute of Anatomy and Histology & Embryology, Neuroscience, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Lu Zhang
- Institute of Anatomy and Histology & Embryology, Neuroscience, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Li-Ping Gao
- Institute of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China; Key Laboratory of Preclinical Study for New Drugs of Gansu province, Lanzhou University, Lanzhou, Gansu, People's Republic of China
| | - Yu-Hong Jing
- Institute of Anatomy and Histology & Embryology, Neuroscience, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, People's Republic of China; Key Laboratory of Preclinical Study for New Drugs of Gansu province, Lanzhou University, Lanzhou, Gansu, People's Republic of China.
| |
Collapse
|
5
|
Gouveri E, Papanas N. Olfactory Dysfunction: A Complication of Diabetes or a Factor That Complicates Glucose Metabolism? A Narrative Review. J Clin Med 2021; 10:jcm10235637. [PMID: 34884338 PMCID: PMC8658580 DOI: 10.3390/jcm10235637] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/21/2021] [Accepted: 11/28/2021] [Indexed: 11/16/2022] Open
Abstract
The present narrative review presents emerging data regarding the association between diabetes mellitus and olfactory dysfunction and discusses the role of olfactory dysfunction in glucose metabolism. We searched relevant published articles in PubMed and Google Scholar until October 2021. Main key words included “olfactory dysfunction”, “diabetes mellitus”, and “glucose metabolism”. Olfactory dysfunction has been associated with diabetes mellitus. Furthermore, it has been proposed to be a diabetic complication, given that it has been linked with microvascular complications, such as diabetic peripheral neuropathy. Interestingly, it has been suggested that olfactory dysfunction is a manifestation of central neuropathy in diabetes, a hypothesis based on the observation that diabetes, olfactory dysfunction, and cognitive decline often coexist. However, evidence is limited and inconsistent. More importantly, olfactory and endocrine systems are closely linked, and olfactory dysfunction plays a significant role in glucose metabolism and obesity. Indeed, food behaviour and energy balance are influenced by olfaction status.
Collapse
Affiliation(s)
| | - Nikolaos Papanas
- Diabetes Centre, Second Department of Internal Medicine, Democritus University of Thrace, 68132 Alexandroupolis, Greece
- Correspondence: ; Fax: +30-25-5135-1723
| |
Collapse
|
6
|
Environmental enrichment ameliorates high-fat diet induced olfactory deficit and decrease of parvalbumin neurons in the olfactory bulb in mice. Brain Res Bull 2021; 179:13-24. [PMID: 34848271 DOI: 10.1016/j.brainresbull.2021.11.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 11/14/2021] [Accepted: 11/24/2021] [Indexed: 11/23/2022]
Abstract
Overweight induced by high-fat diet (HFD) represents one of the major health concerns in modern societies, which can cause lasting peripheral and central metabolic disorders in all age groups. Specifically, childhood obesity could lead to life-long impact on brain development and functioning. On the other hand, environmental enrichment (EE) has been demonstrated to be beneficial for learning and memory. Here, we explored the impact of high-fat diet on olfaction and organization of olfactory bulb cells in adolescent mice, and the effect of EE intervention thereon. Puberty mice (3-week-old) fed with HFD for 10 weeks exhibited poorer odor sensitivity and olfactory memory relative to controls consuming standard chows. The behavioral deficits were rescued in the HFD group with EE intervention. Neuroanatomically, parvalbumin (PV) interneurons in the olfactory bulb (OB) were reduced in the HFD-fed animals relative to control, while EE intervention also normalized this alteration. In contrast, cells expressing calbindin (CB), doublecortin (DCX) in the OB were not altered. Our findings suggest that PV interneurons may play a crucial role in mediating the HFD-induced olfactory deficit in adolescent mice, and can also serve a protective effect of EE against the functional deficit.
Collapse
|
7
|
Kuboki A, Kikuta S, Otori N, Kojima H, Matsumoto I, Reisert J, Yamasoba T. Insulin-Dependent Maturation of Newly Generated Olfactory Sensory Neurons after Injury. eNeuro 2021; 8:ENEURO.0168-21.2021. [PMID: 33906971 PMCID: PMC8143024 DOI: 10.1523/eneuro.0168-21.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 04/20/2021] [Indexed: 12/24/2022] Open
Abstract
Loss of olfactory sensory neurons (OSNs) after injury to the olfactory epithelium (OE) triggers the generation of OSNs that are incorporated into olfactory circuits to restore olfactory sensory perception. This study addresses how insulin receptor-mediated signaling affects the functional recovery of OSNs after OE injury. Insulin levels were reduced in mice by ablating the pancreatic β cells via streptozotocin (STZ) injections. These STZ-induced diabetic and control mice were then intraperitoneally injected with the olfactotoxic drug methimazole to selectively ablate OSNs. The OE of diabetic and control mice regenerated similarly until day 14 after injury. Thereafter, the OE of diabetic mice contained fewer mature and more apoptotic OSNs than control mice. Functionally, diabetic mice showed reduced electro-olfactogram (EOG) responses and their olfactory bulbs (OBs) had fewer c-Fos-active cells following odor stimulation, as well as performed worse in an odor-guided task compared with control mice. Insulin administered intranasally during days 8-13 after injury was sufficient to rescue recovery of OSNs in diabetic mice compared with control levels, while insulin administration between days 1 and 6 did not. During this critical time window on days 8-13 after injury, insulin receptors are highly expressed and intranasal application of an insulin receptor antagonist inhibits regeneration. Furthermore, an insulin-enriched environment could facilitate regeneration even in non-diabetic mice. These results indicate that insulin facilitates the regeneration of OSNs after injury and suggest a critical stage during recovery (8-13 d after injury) during which the maturation of newly generated OSNs is highly dependent on and promoted by insulin.
Collapse
Affiliation(s)
- Akihito Kuboki
- Department of Otolaryngology, Jikei University School of Medicine, Tokyo 105-8461, Japan
- Monell Chemical Senses Center, Philadelphia, PA 19104
| | - Shu Kikuta
- Department of Otolaryngology, Graduate School of Medicine, University of Tokyo, Tokyo 113-8655, Japan
| | - Nobuyoshi Otori
- Department of Otolaryngology, Jikei University School of Medicine, Tokyo 105-8461, Japan
| | - Hiromi Kojima
- Department of Otolaryngology, Jikei University School of Medicine, Tokyo 105-8461, Japan
| | | | | | - Tatsuya Yamasoba
- Department of Otolaryngology, Graduate School of Medicine, University of Tokyo, Tokyo 113-8655, Japan
| |
Collapse
|
8
|
Zhang K, Guo L, Zhang J, Rui G, An G, Zhou Y, Lin J, Xing J, Zhao T, Ding G. tDCS Accelerates the Rehabilitation of MCAO-Induced Motor Function Deficits via Neurogenesis Modulated by the Notch1 Signaling Pathway. Neurorehabil Neural Repair 2020; 34:640-651. [PMID: 32543269 DOI: 10.1177/1545968320925474] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Background. Ischemic stroke carries a high mortality rate and is a leading cause of severe neurological disability. However, the efficacy of current therapeutic options remains limited. Objective. We aimed to investigate the treatment efficacy of transcranial direct current stimulation (tDCS) in motor function rehabilitation after ischemic stroke and explore the underlying mechanisms. Methods. Male Sprague-Dawley rats with epicranial electrodes were used to establish pathogenetic model through temporary right middle cerebral artery occlusion (MCAO). Subsequently, animals were randomly divided into 4 groups: MCAO + tDCS/sham tDCS, Control + tDCS/sham tDCS. Animals in the groups with tDCS underwent 10 days of cathodal tDCS totally (500 µA, 15 minutes, once a day). During and after tDCS treatment, the motor functions of the animals, ischemic damage area, proliferation and differentiation of neural stem cells (NSCs), and distribution, and protein expression of Notch1 signaling molecules were detected. Results. The rehabilitation of MCAO-induced motor function deficits was dramatically accelerated by tDCS treatment. NSC proliferation in the subventricular zone (SVZ) was significantly increased after MCAO surgery, and tDCS treatment promoted this process. Additionally, NSCs probably migrated from the SVZ to the ischemic striatum and then differentiated into neurons and oligodendrocytes after MCAO surgery, both of which processes were accelerated by tDCS treatment. Finally, tDCS treatment inhibited the activation of Notch1 signaling in NSCs in the ischemic striatum, which may be involved in NSC differentiation in the MCAO model. Conclusion. Our results suggest that tDCS may exert therapeutic efficacy after ischemic stroke in a regenerative medical perspective.
Collapse
Affiliation(s)
- Keying Zhang
- Department of Radiation Biology, Fourth Military Medical University, Xi'an, China.,Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Xi'an, China
| | - Ling Guo
- Department of Radiation Biology, Fourth Military Medical University, Xi'an, China.,Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Xi'an, China
| | - Junping Zhang
- Department of Radiation Biology, Fourth Military Medical University, Xi'an, China.,Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Xi'an, China
| | - Gang Rui
- Department of Radiation Biology, Fourth Military Medical University, Xi'an, China.,Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Xi'an, China
| | - Guangzhou An
- Department of Radiation Biology, Fourth Military Medical University, Xi'an, China.,Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Xi'an, China
| | - Yan Zhou
- Department of Radiation Biology, Fourth Military Medical University, Xi'an, China.,Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Xi'an, China
| | - Jiajin Lin
- Department of Radiation Biology, Fourth Military Medical University, Xi'an, China.,Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Xi'an, China
| | - Junling Xing
- Department of Radiation Biology, Fourth Military Medical University, Xi'an, China.,Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Xi'an, China
| | - Tao Zhao
- Department of Radiation Biology, Fourth Military Medical University, Xi'an, China.,Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Xi'an, China
| | - Guirong Ding
- Department of Radiation Biology, Fourth Military Medical University, Xi'an, China.,Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, Xi'an, China
| |
Collapse
|