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Ben Musa R, Cornelius-Green J, Zhang H, Li DP, Kline DD, Hasser EM, Cummings KJ. Orexin Facilitates the Peripheral Chemoreflex via Corticotropin-Releasing Hormone Neurons Projecting to the Nucleus of the Solitary Tract. J Neurosci 2024; 44:e2383232024. [PMID: 38789262 PMCID: PMC11223477 DOI: 10.1523/jneurosci.2383-23.2024] [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: 01/02/2024] [Revised: 04/14/2024] [Accepted: 05/13/2024] [Indexed: 05/26/2024] Open
Abstract
We previously showed that orexin neurons are activated by hypoxia and facilitate the peripheral chemoreflex (PCR)-mediated hypoxic ventilatory response (HVR), mostly by promoting the respiratory frequency response. Orexin neurons project to the nucleus of the solitary tract (nTS) and the paraventricular nucleus of the hypothalamus (PVN). The PVN contributes significantly to the PCR and contains nTS-projecting corticotropin-releasing hormone (CRH) neurons. We hypothesized that in male rats, orexin neurons contribute to the PCR by activating nTS-projecting CRH neurons. We used neuronal tract tracing and immunohistochemistry (IHC) to quantify the degree that hypoxia activates PVN-projecting orexin neurons. We coupled this with orexin receptor (OxR) blockade with suvorexant (Suvo, 20 mg/kg, i.p.) to assess the degree that orexin facilitates the hypoxia-induced activation of CRH neurons in the PVN, including those projecting to the nTS. In separate groups of rats, we measured the PCR following systemic orexin 1 receptor (Ox1R) blockade (SB-334867; 1 mg/kg) and specific Ox1R knockdown in PVN. OxR blockade with Suvo reduced the number of nTS and PVN neurons activated by hypoxia, including those CRH neurons projecting to nTS. Hypoxia increased the number of activated PVN-projecting orexin neurons but had no effect on the number of activated nTS-projecting orexin neurons. Global Ox1R blockade and partial Ox1R knockdown in the PVN significantly reduced the PCR. Ox1R knockdown also reduced the number of activated PVN neurons and the number of activated tyrosine hydroxylase neurons in the nTS. Our findings suggest orexin facilitates the PCR via nTS-projecting CRH neurons expressing Ox1R.
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Affiliation(s)
- Ruwaida Ben Musa
- Department of Biomedical Sciences, College of Veterinary Medicine, Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211
| | - Jennifer Cornelius-Green
- Department of Biomedical Sciences, College of Veterinary Medicine, Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211
| | - Hua Zhang
- Department of Medicine, Center for Precision Medicine, School of Medicine, University of Missouri, Columbia, Missouri 65212
| | - De-Pei Li
- Department of Medicine, Center for Precision Medicine, School of Medicine, University of Missouri, Columbia, Missouri 65212
| | - David D Kline
- Department of Biomedical Sciences, College of Veterinary Medicine, Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211
| | - Eileen M Hasser
- Department of Biomedical Sciences, College of Veterinary Medicine, Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211
| | - Kevin J Cummings
- Department of Biomedical Sciences, College of Veterinary Medicine, Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211
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Wrzesień A, Andrzejewski K, Jampolska M, Kaczyńska K. Respiratory Dysfunction in Alzheimer's Disease-Consequence or Underlying Cause? Applying Animal Models to the Study of Respiratory Malfunctions. Int J Mol Sci 2024; 25:2327. [PMID: 38397004 PMCID: PMC10888758 DOI: 10.3390/ijms25042327] [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: 01/17/2024] [Revised: 02/09/2024] [Accepted: 02/14/2024] [Indexed: 02/25/2024] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative brain disease that is the most common cause of dementia among the elderly. In addition to dementia, which is the loss of cognitive function, including thinking, remembering, and reasoning, and behavioral abilities, AD patients also experience respiratory disturbances. The most common respiratory problems observed in AD patients are pneumonia, shortness of breath, respiratory muscle weakness, and obstructive sleep apnea (OSA). The latter is considered an outcome of Alzheimer's disease and is suggested to be a causative factor. While this narrative review addresses the bidirectional relationship between obstructive sleep apnea and Alzheimer's disease and reports on existing studies describing the most common respiratory disorders found in patients with Alzheimer's disease, its main purpose is to review all currently available studies using animal models of Alzheimer's disease to study respiratory impairments. These studies on animal models of AD are few in number but are crucial for establishing mechanisms, causation, implementing potential therapies for respiratory disorders, and ultimately applying these findings to clinical practice. This review summarizes what is already known in the context of research on respiratory disorders in animal models, while pointing out directions for future research.
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Affiliation(s)
| | | | | | - Katarzyna Kaczyńska
- Department of Respiration Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, 02-106 Warsaw, Poland; (A.W.); (K.A.); (M.J.)
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Lusk S, Ward CS, Chang A, Twitchell-Heyne A, Fattig S, Allen G, Jankowsky J, Ray R. An automated respiratory data pipeline for waveform characteristic analysis. J Physiol 2023; 601:4767-4806. [PMID: 37786382 PMCID: PMC10841337 DOI: 10.1113/jp284363] [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: 01/12/2023] [Accepted: 08/11/2023] [Indexed: 10/04/2023] Open
Abstract
Comprehensive and accurate analysis of respiratory and metabolic data is crucial to modelling congenital, pathogenic and degenerative diseases converging on autonomic control failure. A lack of tools for high-throughput analysis of respiratory datasets remains a major challenge. We present Breathe Easy, a novel open-source pipeline for processing raw recordings and associated metadata into operative outcomes, publication-worthy graphs and robust statistical analyses including QQ and residual plots for assumption queries and data transformations. This pipeline uses a facile graphical user interface for uploading data files, setting waveform feature thresholds and defining experimental variables. Breathe Easy was validated against manual selection by experts, which represents the current standard in the field. We demonstrate Breathe Easy's utility by examining a 2-year longitudinal study of an Alzheimer's disease mouse model to assess contributions of forebrain pathology in disordered breathing. Whole body plethysmography has become an important experimental outcome measure for a variety of diseases with primary and secondary respiratory indications. Respiratory dysfunction, while not an initial symptom in many of these disorders, often drives disability or death in patient outcomes. Breathe Easy provides an open-source respiratory analysis tool for all respiratory datasets and represents a necessary improvement upon current analytical methods in the field. KEY POINTS: Respiratory dysfunction is a common endpoint for disability and mortality in many disorders throughout life. Whole body plethysmography in rodents represents a high face-value method for measuring respiratory outcomes in rodent models of these diseases and disorders. Analysis of key respiratory variables remains hindered by manual annotation and analysis that leads to low throughput results that often exclude a majority of the recorded data. Here we present a software suite, Breathe Easy, that automates the process of data selection from raw recordings derived from plethysmography experiments and the analysis of these data into operative outcomes and publication-worthy graphs with statistics. We validate Breathe Easy with a terabyte-scale Alzheimer's dataset that examines the effects of forebrain pathology on respiratory function over 2 years of degeneration.
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Affiliation(s)
- Savannah Lusk
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Christopher S. Ward
- Department of Integrative Physiology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Andersen Chang
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Shaun Fattig
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Genevera Allen
- Departments of Electrical and Computer Engineering, Statistics, and Computer Science, Rice University, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX 77030, USA
| | - Joanna Jankowsky
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
- Departments of Neurology, Neurosurgery, and Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Russell Ray
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
- McNair Medical Institute, Houston, TX 77030, USA
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Alves SS, de Oliveira JAC, Lazarini-Lopes W, Servilha-Menezes G, Grigório-de-Sant'Ana M, Del Vecchio F, Mazzei RF, Sousa Almeida S, da Silva Junior RMP, Garcia-Cairasco N. Audiogenic Seizures in the Streptozotocin-Induced Rat Alzheimer's Disease Model. J Alzheimers Dis 2023:JAD230153. [PMID: 37393501 DOI: 10.3233/jad-230153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/03/2023]
Abstract
BACKGROUND Alzheimer's disease (AD) is a neurodegenerative and progressive disorder with no cure and constant failures in clinical trials. The main AD hallmarks are amyloid-β (Aβ) plaques, neurofibrillary tangles, and neurodegeneration. However, many other events have been implicated in AD pathogenesis. Epilepsy is a common comorbidity of AD and there is important evidence indicating a bidirectional link between these two disorders. Some studies suggest that disturbed insulin signaling might play an important role in this connection. OBJECTIVE To understand the effects of neuronal insulin resistance in the AD-epilepsy link. METHODS We submitted the streptozotocin (STZ) induced rat AD Model (icv-STZ AD) to an acute acoustic stimulus (AS), a known trigger of seizures. We also assessed animals' performance in the memory test, the Morris water maze and the neuronal activity (c-Fos protein) induced by a single audiogenic seizure in regions that express high levels of insulin receptors. RESULTS We identified significant memory impairment and seizures in 71.43% of all icv-STZ/AS rats, in contrast to 22.22% of the vehicle group. After seizures, icv-STZ/AS rats presented higher number of c-Fos immunopositive cells in hippocampal, cortical, and hypothalamic regions. CONCLUSION STZ may facilitate seizure generation and propagation by impairment of neuronal function, especially in regions that express high levels of insulin receptors. The data presented here indicate that the icv-STZ AD model might have implications not only for AD, but also for epilepsy. Finally, impaired insulin signaling might be one of the mechanisms by which AD presents a bidirectional connection to epilepsy.
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Affiliation(s)
- Suélen Santos Alves
- Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School - University of São Paulo (FMRP-USP), São Paulo, Brazil
| | | | - Willian Lazarini-Lopes
- Department of Pharmacology, Ribeirão Preto Medical School - University of São Paulo (FMRP-USP), São Paulo, Brazil
| | - Gabriel Servilha-Menezes
- Department of Physiology, Ribeirão Preto Medical School - University of São Paulo (FMRP-USP), São Paulo, Brazil
| | | | - Flavio Del Vecchio
- Department of Physiology, Ribeirão Preto Medical School - University of São Paulo (FMRP-USP), São Paulo, Brazil
| | - Rodrigo Focosi Mazzei
- Department of Psychology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto - University of São Paulo (FFCLRP-USP), São Paulo, Brazil
| | - Sebastião Sousa Almeida
- Department of Psychology, Faculty of Philosophy, Sciences and Letters of Ribeirão Preto - University of São Paulo (FFCLRP-USP), São Paulo, Brazil
| | | | - Norberto Garcia-Cairasco
- Department of Neurosciences and Behavioral Sciences, Ribeirão Preto Medical School - University of São Paulo (FMRP-USP), São Paulo, Brazil
- Department of Physiology, Ribeirão Preto Medical School - University of São Paulo (FMRP-USP), São Paulo, Brazil
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Humphrey CM, Hooker JW, Thapa M, Wilcox MJ, Ostrowski D, Ostrowski TD. Synaptic loss and gliosis in the nucleus tractus solitarii with streptozotocin-induced Alzheimer's disease. Brain Res 2023; 1801:148202. [PMID: 36521513 PMCID: PMC9840699 DOI: 10.1016/j.brainres.2022.148202] [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: 09/29/2022] [Revised: 11/21/2022] [Accepted: 12/09/2022] [Indexed: 12/14/2022]
Abstract
Obstructive sleep apnea is highly prevalent in Alzheimer's disease (AD). However, brainstem centers controlling respiration have received little attention in AD research, and mechanisms behind respiratory dysfunction in AD are not understood. The nucleus tractus solitarii (nTS) is an important brainstem center for respiratory control and chemoreflex function. Alterations of nTS integrity, like those shown in AD patients, likely affect neuronal processing and adequate control of breathing. We used the streptozotocin-induced rat model of AD (STZ-AD) to analyze cellular changes in the nTS that corroborate previously documented respiratory dysfunction. We used 2 common dosages of STZ (2 and 3 mg/kg STZ) for model induction and evaluated the early impact on cell populations in the nTS. The hippocampus served as control region to identify site-specific effects of STZ. There was significant atrophy in the caudal nTS of the 3 mg/kg STZ-AD group only, an area known to integrate chemoafferent information. Also, the hippocampus had significant atrophy with the highest STZ dosage tested. Both STZ-AD groups showed respiratory dysfunction along with multiple indices for astroglial and microglial activation. These changes were primarily located in the caudal and intermediate nTS. While there was no change of astrocytes in the hippocampus, microglial activation was accompanied by a reduction in synaptic density. Together, our data demonstrate that STZ-AD induces site-specific effects on all major cell types, primarily in the caudal/intermediate nTS. Both STZ dosages used in this study produced a similar outcome and can be used for future studies examining the initial symptoms of STZ-AD.
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Affiliation(s)
- Chuma M Humphrey
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University, 800 W. Jefferson St., Kirksville, MO, USA
| | - John W Hooker
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University, 800 W. Jefferson St., Kirksville, MO, USA
| | - Mahima Thapa
- Department of Biology, Truman State University, 100 E. Normal Ave., Kirksville, MO, USA
| | - Mason J Wilcox
- Department of Biology, Truman State University, 100 E. Normal Ave., Kirksville, MO, USA
| | - Daniela Ostrowski
- Department of Biology, Truman State University, 100 E. Normal Ave., Kirksville, MO, USA
| | - Tim D Ostrowski
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University, 800 W. Jefferson St., Kirksville, MO, USA.
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Hypoxic and Hypercapnic Responses in Transgenic Murine Model of Alzheimer’s Disease Overexpressing Human AβPP: The Effects of Pretreatment with Memantine and Rivastigmine. Int J Mol Sci 2022; 23:ijms23116004. [PMID: 35682682 PMCID: PMC9180806 DOI: 10.3390/ijms23116004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 05/24/2022] [Accepted: 05/25/2022] [Indexed: 12/03/2022] Open
Abstract
Despite the severe respiratory problems reducing the quality of life for Alzheimer’s disease (AD) patients, their causes are poorly understood. We aimed to investigate hypoxic and hypercapnic respiratory responses in a transgenic mouse model of AD (AβPP V717I) overexpressing AβPP and mimicking early-onset AD. The cholinesterase inhibitor rivastigmine and the NMDA receptor antagonist memantine were used to investigate the effects of drugs, used to treat AD cognitive dysfunction, on breathing in hypoxia and hypercapnia. We found a significant increase in the respiratory response to hypercapnia and no difference in the hypoxic response in APP+ mice, compared with the control group (APP−). Memantine had no effect on respiration in either group, including responses to hypoxia and hypercapnia. Rivastigmine depressed resting ventilation and response to hypercapnia irrespective of the mice genotype. Reduction in hypoxia-augmented ventilation by rivastigmine was observed only in APP+ mice, which exhibited lower acetylcholinesterase activity in the hippocampus. Treatment with rivastigmine reduced the enzyme activity in both groups equally in the hippocampus and brainstem. The increased ventilatory response to hypercapnia in transgenic mice may indicate alterations in chemoreceptive respiratory nuclei, resulting in increased CO2 sensitivity. Rivastigmine is a potent reductant of normoxic and hypercapnic respiration in APP+ and APP− mice.
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Ehlen JC, Forman CM, Ostrowski D, Ostrowski TD. Autonomic Dysfunction Impairs Baroreflex Function in an Alzheimer's Disease Animal Model. J Alzheimers Dis 2022; 90:1449-1464. [PMID: 36278348 PMCID: PMC9742304 DOI: 10.3233/jad-220496] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) patients frequently present with orthostatic hypotension. This inability to reflexively increase blood pressure on standing is a serious health concern and increases the risk of stroke and cardiovascular diseases. OBJECTIVE Since there are no clear mechanisms for orthostatic hypotension in human AD, the present study assessed the autonomic changes that could explain this comorbidity in an AD animal model. METHODS We used the established streptozotocin-induced rat model of AD (STZ-AD), which mimics many hallmark symptoms of sporadic AD in humans. Baroreflex responses were analyzed in anesthetized STZ-AD rats using femoral catheterization for blood pressure and heart rate, and autonomic activity was assessed using specific blockers and splanchnic sympathetic nerve recordings. Expression levels of autonomic receptors at the heart were examined using the western blot technique. RESULTS Baroreflex function in STZ-AD showed a blunted heart rate (HR) response to low blood pressure challenges, and the maximal sympathetic nerve activity was reduced. Conversely, HR responses to high blood pressure were similar to control, indicating no change in parasympathetic nerve activity. Under resting conditions, autonomic blockade demonstrated a baseline shift to increased sympathetic tone in STZ-AD. Protein expression levels of beta-1 adrenergic receptor and muscarinic acetylcholine receptor M2 in the heart were unchanged. CONCLUSION Our study provides the first data on the pathological influence of AD on baroreflex function, which primarily affected the sympathetic nervous system in STZ-AD. These results represent the first mechanisms that may correlate with the orthostatic hypotension in human AD.
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Affiliation(s)
- John C. Ehlen
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University of Health Sciences, Kirksville, MO, USA
| | | | | | - Tim D. Ostrowski
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University of Health Sciences, Kirksville, MO, USA
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Vicente MC, Humphrey CM, Gargaglioni LH, Ostrowski TD. Decreased excitability of locus coeruleus neurons during hypercapnia is exaggerated in the streptozotocin-model of Alzheimer's disease. Exp Neurol 2020; 328:113250. [PMID: 32088169 DOI: 10.1016/j.expneurol.2020.113250] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 02/04/2020] [Accepted: 02/17/2020] [Indexed: 10/25/2022]
Abstract
The locus coeruleus (LC) is a pontine nucleus important for respiratory control and central chemoreception. It is affected in Alzheimer's disease (AD) and alteration of LC cell function may account for respiratory problems observed in AD patients. In the current study, we tested the electrophysiological properties and CO2/pH sensitivity of LC neurons in a model for AD. Sporadic AD was induced in rats by intracerebroventricular injection of 2 mg/kg streptozotocin (STZ), which induces behavioral and molecular impairments found in AD. LC neurons were recorded using the patch clamp technique and tested for responses to CO2 (10% CO2, pH = 7.0). The majority (~60%) of noradrenergic LC neurons in adult rats were inhibited by CO2 exposure as indicated by a significant decrease in action potential (AP) discharge to step depolarizations. The STZ-AD rat model had a greater sensitivity to CO2 than controls. The increased CO2-sensitivity was demonstrated by a significantly stronger inhibition of activity during hypercapnia that was in part due to hyperpolarization of the resting membrane potential. Reduction of AP discharge in both groups was generally accompanied by lower LC network activity, depolarized AP threshold, increased AP repolarization, and increased current through a subpopulation of voltage-gated K+ channels (KV). The latter was indicated by enhanced transient KV currents particularly in the STZ-AD group. Interestingly, steady-state KV currents were reduced under hypercapnia, a change that would favor enhanced AP discharge. However, the collective response of most LC neurons in adult rats, and particularly those in the STZ-AD group, was inhibited by CO2.
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Affiliation(s)
- Mariane C Vicente
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University of Health Sciences, Kirksville, MO, USA; Department of Animal Morphology and Physiology, Sao Paulo State University-UNESP/FCAV at Jaboticabal, SP, Brazil
| | - Chuma M Humphrey
- Department of Biology, Truman State University, Kirksville, MO, USA
| | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, Sao Paulo State University-UNESP/FCAV at Jaboticabal, SP, Brazil
| | - Tim D Ostrowski
- Department of Physiology, Kirksville College of Osteopathic Medicine, A.T. Still University of Health Sciences, Kirksville, MO, USA.
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Zhao P, Qian X, Nie Y, Sun N, Wang Z, Wu J, Wei C, Ma R, Wang Z, Chai G, Li Y. Neuropeptide S Ameliorates Cognitive Impairment of APP/PS1 Transgenic Mice by Promoting Synaptic Plasticity and Reducing Aβ Deposition. Front Behav Neurosci 2019; 13:138. [PMID: 31293402 PMCID: PMC6603143 DOI: 10.3389/fnbeh.2019.00138] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 06/06/2019] [Indexed: 12/02/2022] Open
Abstract
Alzheimer’s disease (AD) is a devastating disease in the elderly with no known effective treatment. It is characterized by progressive deterioration of memory and cognition. Many new potential targets are being investigated to develop effective therapeutic strategies for AD. Neuropeptide S (NPS) is an endogenous peptide in the central nervous system, which has been shown to play a beneficial role in learning and memory. However, whether NPS can ameliorate cognitive deficits in AD remains unclear. In this study, we examined the effects of NPS treatment on the cognitive behaviors and pathological hallmarks in 8-month-old APPswe/PS1dE9 (APP/PS1) AD mice. We found that the APP/PS1 mice exhibited lower levels of NPS receptors (NPSRs) in the hippocampal area, and NPS administration increased c-Fos expression in the hippocampus and cortex, which suggests the NPS/NPSR system may contribute to the pathogenesis of AD. After an intracerebroventricular injection of NPS (1 nmol) for 2 weeks, we found NPS treatment ameliorated spatial memory deficits and promoted dendrite ramification and spine generation in hippocampal CA1 neurons, which was accompanied by the upregulation of postsynaptic density protein 95 (PSD95) and synapsin1. We also demonstrated that the injection of NPS decreased Aβ plaque deposits by decreasing the γ-secretase activity and the phosphorylation of APP at Thr668. Furthermore, application of NPS reversed the deficits in hippocampal late-phase long-term potentiation (LTP). These findings suggest NPS attenuated cognitive deficits by reducing pathological features in APP/PS1 mice, and NPS might be a potential therapeutic agent for AD.
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Affiliation(s)
- Peng Zhao
- Wuxi Medical School, Jiangnan University, Wuxi, China
| | - Xiaohang Qian
- Wuxi Medical School, Jiangnan University, Wuxi, China
| | - Yunjuan Nie
- Wuxi Medical School, Jiangnan University, Wuxi, China
| | - Na Sun
- Wuxi Medical School, Jiangnan University, Wuxi, China
| | | | - Jiajun Wu
- Wuxi Medical School, Jiangnan University, Wuxi, China
| | - Chen Wei
- Wuxi Medical School, Jiangnan University, Wuxi, China
| | - Ruikun Ma
- Wuxi Medical School, Jiangnan University, Wuxi, China
| | - Zhe Wang
- Wuxi Medical School, Jiangnan University, Wuxi, China
| | - Gaoshang Chai
- Wuxi Medical School, Jiangnan University, Wuxi, China
| | - Yuqing Li
- Wuxi Medical School, Jiangnan University, Wuxi, China.,Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, United States
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