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Lantz MJ, Roberts AM, Delgado DD, Nichols RA. The neuroprotective N-terminal amyloid-β core hexapeptide reverses reactive gliosis and gliotoxicity in Alzheimer's disease pathology models. J Neuroinflammation 2023; 20:129. [PMID: 37245024 DOI: 10.1186/s12974-023-02807-9] [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: 12/27/2022] [Accepted: 05/16/2023] [Indexed: 05/29/2023] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by accumulation of extracellular amyloid beta (Aβ) and intracellular neurofibrillary tangles, leading to chronic activation of astrocytes and microglia and persistent neuroinflammation. Aβ-linked activation of microglia and astrocytes leads to increased intracellular calcium and production of proinflammatory cytokines, impacting the progression of neurodegeneration. An N-terminal Aβ fragment (Aβ1-15) and a shorter hexapeptide core sequence within the N-Aβ fragment (N-Aβcore: Aβ10-15) have previously been shown to protect against Aβ-induced mitochondrial dysfunction, oxidative stress and apoptosis in neurons and rescue synaptic and spatial memory deficits in an APP/PSEN1 mouse model. Here, we hypothesized that the N-Aβ fragment and N-Aβcore are protective against Aβ-induced gliotoxicity, promoting a neuroprotective environment and potentially alleviating the characteristically persistent neuroinflammation present in AD. METHODS We treated ex vivo organotypic brain slice cultures from an aged familial AD mouse model, 5xFAD, with the N-Aβcore and used immunocytochemistry to assess the impact on astrogliosis and microgliosis and alterations in synaptophysin-positive puncta engulfed by microglia. Isolated neuron/glia cultures, mixed glial cultures or a microglial cell line were treated with oligomeric human Aβ at concentrations mimicking the pathogenic concentrations (μM) observed in AD in the absence or presence of the non-toxic N-terminal Aβ fragments. Resultant changes in synaptic density, gliosis, oxidative stress, mitochondrial dysfunction, apoptosis, and the expression and release of proinflammatory markers were then determined. RESULTS We demonstrate that the N-terminal Aβ fragments mitigated the phenotypic switch leading to astrogliosis and microgliosis induced by pathological concentrations of Aβ in mixed glial cultures and organotypic brain slice cultures from the transgenic 5xFAD mouse model, while protecting against Aβ-induced oxidative stress, mitochondrial dysfunction and apoptosis in isolated astrocytes and microglia. Moreover, the addition of the N-Aβcore attenuated the expression and release of proinflammatory mediators in microglial cells activated by Aβ and rescued microglia-mediated loss of synaptic elements induced by pathological levels of Aβ. CONCLUSIONS Together, these findings indicate the protective functions of the N-terminal Aβ fragments extend to reactive gliosis and gliotoxicity induced by Aβ, by preventing or reversing glial reactive states indicative of neuroinflammation and synaptic loss central to AD pathogenesis.
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Affiliation(s)
- Megan J Lantz
- Department of Cell and Molecular Biology, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Alyssa M Roberts
- Department of Cell and Molecular Biology, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Donovan D Delgado
- Department of Cell and Molecular Biology, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Robert A Nichols
- Department of Cell and Molecular Biology, University of Hawai'i at Mānoa, Honolulu, HI, USA.
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Transcriptome Profile of Nicotinic Receptor-Linked Sensitization of Beta Amyloid Neurotoxicity. Sci Rep 2020; 10:5696. [PMID: 32231242 PMCID: PMC7105468 DOI: 10.1038/s41598-020-62726-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 03/18/2020] [Indexed: 11/29/2022] Open
Abstract
Understanding the specific gene changes underlying the prodromic stages of Alzheimer’s disease pathogenesis will aid the development of new, targeted therapeutic strategies for this neurodegenerative disorder. Here, we employed RNA-sequencing to analyze global differential gene expression in a defined model nerve cell line expressing α4β2 nicotinic receptors (nAChRs), high-affinity targets for beta amyloid (Aβ). The nAChR-expressing neuronal cells were treated with nanomolar Aβ1–42 to gain insights into the molecular mechanisms underlying Aβ-induced neurotoxicity in the presence of this sensitizing target receptor. We identified 15 genes (out of 15,336) that were differentially expressed upon receptor-linked Aβ treatment. Genes up-regulated with Aβ treatment were associated with calcium signaling and axonal vesicle transport (including the α4 nAChR subunit, the calcineurin regulator RCAN3, and KIF1C of the kinesin family). Downregulated genes were associated with metabolic, apoptotic or DNA repair pathways (including APBA3, PARP1 and RAB11). Validation of the differential expression was performed via qRT-PCR and immunoblot analysis in the defined model nerve cell line and primary mouse neurons. Further verification was performed using immunocytochemistry. In conclusion, we identified apparent changes in gene expression on Aβ treatment in the presence of the sensitizing nAChRs, linked to early-stage Aβ-induced neurotoxicity, which may represent novel therapeutic targets.
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The Interplay between Ca 2+ Signaling Pathways and Neurodegeneration. Int J Mol Sci 2019; 20:ijms20236004. [PMID: 31795242 PMCID: PMC6928941 DOI: 10.3390/ijms20236004] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 11/18/2019] [Accepted: 11/25/2019] [Indexed: 12/13/2022] Open
Abstract
Calcium (Ca2+) homeostasis is essential for cell maintenance since this ion participates in many physiological processes. For example, the spatial and temporal organization of Ca2+ signaling in the central nervous system is fundamental for neurotransmission, where local changes in cytosolic Ca2+ concentration are needed to transmit information from neuron to neuron, between neurons and glia, and even regulating local blood flow according to the required activity. However, under pathological conditions, Ca2+ homeostasis is altered, with increased cytoplasmic Ca2+ concentrations leading to the activation of proteases, lipases, and nucleases. This review aimed to highlight the role of Ca2+ signaling in neurodegenerative disease-related apoptosis, where the regulation of intracellular Ca2+ homeostasis depends on coordinated interactions between the endoplasmic reticulum, mitochondria, and lysosomes, as well as specific transport mechanisms. In neurodegenerative diseases, alterations-increased oxidative stress, energy metabolism alterations, and protein aggregation have been identified. The aggregation of α-synuclein, β-amyloid peptide (Aβ), and huntingtin all adversely affect Ca2+ homeostasis. Due to the mounting evidence for the relevance of Ca2+ signaling in neuroprotection, we would focus on the expression and function of Ca2+ signaling-related proteins, in terms of the effects on autophagy regulation and the onset and progression of neurodegenerative diseases.
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Sun JL, Stokoe SA, Roberts JP, Sathler MF, Nip KA, Shou J, Ko K, Tsunoda S, Kim S. Co-activation of selective nicotinic acetylcholine receptors is required to reverse beta amyloid-induced Ca 2+ hyperexcitation. Neurobiol Aging 2019; 84:166-177. [PMID: 31629115 DOI: 10.1016/j.neurobiolaging.2019.09.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 08/27/2019] [Accepted: 09/13/2019] [Indexed: 12/20/2022]
Abstract
Beta-amyloid (Aβ) peptide accumulation has long been implicated in the pathogenesis of Alzheimer's disease (AD). Hippocampal network hyperexcitability in the early stages of the disease leads to increased epileptiform activity and eventually cognitive decline. We found that acute application of 250 nM soluble Aβ42 oligomers increased Ca2+ activity in hippocampal neurons in parallel with a significant decrease in activity in Aβ42-treated interneurons. A potential target of Aβ42 is the nicotinic acetylcholine receptor (nAChR). Three major subtypes of nAChRs (α7, α4β2, and α3β4) have been reported in the human hippocampus. Simultaneous inhibition of both α7 and α4β2 nAChRs mimicked the Aβ42 effects on both excitatory and inhibitory neurons. However, inhibition of all 3 subtypes showed the opposite effect. Importantly, simultaneous activation of α7 and α4β2 nAChRs was required to reverse Aβ42-induced neuronal hyperexcitation. We suggest co-activation of α7 and α4β2 nAChRs is required to reverse Aβ42-induced Ca2+ hyperexcitation.
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Affiliation(s)
- Julianna L Sun
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; Molecular, Cellular and Integrative Neurosciences Program, Fort Collins, CO, USA
| | - Sarah A Stokoe
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; Molecular, Cellular and Integrative Neurosciences Program, Fort Collins, CO, USA
| | - Jessica P Roberts
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; Molecular, Cellular and Integrative Neurosciences Program, Fort Collins, CO, USA
| | - Matheus F Sathler
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Kaila A Nip
- Cellular and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO, USA
| | - Jiayi Shou
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Kaitlyn Ko
- Poudre High School, Fort Collins, CO, USA
| | - Susan Tsunoda
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; Molecular, Cellular and Integrative Neurosciences Program, Fort Collins, CO, USA
| | - Seonil Kim
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA; Molecular, Cellular and Integrative Neurosciences Program, Fort Collins, CO, USA; Cellular and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO, USA.
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5
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Forest KH, Nichols RA. Assessing Neuroprotective Agents for Aβ-Induced Neurotoxicity. Trends Mol Med 2019; 25:685-695. [DOI: 10.1016/j.molmed.2019.05.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 05/17/2019] [Accepted: 05/29/2019] [Indexed: 12/14/2022]
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Fabiani C, Antollini SS. Alzheimer's Disease as a Membrane Disorder: Spatial Cross-Talk Among Beta-Amyloid Peptides, Nicotinic Acetylcholine Receptors and Lipid Rafts. Front Cell Neurosci 2019; 13:309. [PMID: 31379503 PMCID: PMC6657435 DOI: 10.3389/fncel.2019.00309] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 06/25/2019] [Indexed: 12/17/2022] Open
Abstract
Biological membranes show lateral and transverse asymmetric lipid distribution. Cholesterol (Chol) localizes in both hemilayers, but in the external one it is mostly condensed in lipid-ordered microdomains (raft domains), together with saturated phosphatidyl lipids and sphingolipids (including sphingomyelin and glycosphingolipids). Membrane asymmetries induce special membrane biophysical properties and behave as signals for several physiological and/or pathological processes. Alzheimer’s disease (AD) is associated with a perturbation in different membrane properties. Amyloid-β (Aβ) plaques and neurofibrillary tangles of tau protein together with neuroinflammation and neurodegeneration are the most characteristic cellular changes observed in this disease. The extracellular presence of Aβ peptides forming senile plaques, together with soluble oligomeric species of Aβ, are considered the major cause of the synaptic dysfunction of AD. The association between Aβ peptide and membrane lipids has been extensively studied. It has been postulated that Chol content and Chol distribution condition Aβ production and posterior accumulation in membranes and, hence, cell dysfunction. Several lines of evidence suggest that Aβ partitions in the cell membrane accumulate mostly in raft domains, the site where the cleavage of the precursor AβPP by β- and γ- secretase is also thought to occur. The main consequence of the pathogenesis of AD is the disruption of the cholinergic pathways in the cerebral cortex and in the basal forebrain. In parallel, the nicotinic acetylcholine receptor has been extensively linked to membrane properties. Since its transmembrane domain exhibits extensive contacts with the surrounding lipids, the acetylcholine receptor function is conditioned by its lipid microenvironment. The nicotinic acetylcholine receptor is present in high-density clusters in the cell membrane where it localizes mainly in lipid-ordered domains. Perturbations of sphingomyelin or cholesterol composition alter acetylcholine receptor location. Therefore, Aβ processing, Aβ partitioning, and acetylcholine receptor location and function can be manipulated by changes in membrane lipid biophysics. Understanding these mechanisms should provide insights into new therapeutic strategies for prevention and/or treatment of AD. Here, we discuss the implications of lipid-protein interactions at the cell membrane level in AD.
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Affiliation(s)
- Camila Fabiani
- Instituto de Investigaciones Bioquímicas de Bahía Blanca CONICET-UNS, Bahía Blanca, Argentina.,Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
| | - Silvia S Antollini
- Instituto de Investigaciones Bioquímicas de Bahía Blanca CONICET-UNS, Bahía Blanca, Argentina.,Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
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Neuroprotective effects of 1`δ-1`-acetoxyeugenol acetate on Aβ(25-35) induced cognitive dysfunction in mice. Biomed Pharmacother 2019; 109:1454-1461. [DOI: 10.1016/j.biopha.2018.10.189] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 10/30/2018] [Accepted: 10/31/2018] [Indexed: 12/11/2022] Open
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8
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Song Q, Li Y, Cao Z, Liu H, Tian C, Yang Z, Qiang X, Tan Z, Deng Y. Discovery of novel 2,5-dihydroxyterephthalamide derivatives as multifunctional agents for the treatment of Alzheimer's disease. Bioorg Med Chem 2018; 26:6115-6127. [PMID: 30470598 DOI: 10.1016/j.bmc.2018.11.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 11/10/2018] [Accepted: 11/12/2018] [Indexed: 10/27/2022]
Abstract
A series of 2,5-dihydroxyterephthalamide derivatives were designed, synthesized and evaluated as multifunctional agents for the treatment of Alzheimer's disease. In vitro assays demonstrated that most of the derivatives exhibited good multifunctional activities. Among them, compound 9d showed the best inhibitory activity against both RatAChE and EeAChE (IC50 = 0.56 μM and 5.12 μM, respectively). Moreover, 9d exhibited excellent inhibitory effects on self-induced Aβ1-42 aggregation (IC50 = 3.05 μM) and Cu2+-induced Aβ1-42 aggregation (71.7% at 25.0 μM), and displayed significant disaggregation ability to self- and Cu2+-induced Aβ1-42 aggregation fibrils (75.2% and 77.2% at 25.0 μM, respectively). Furthermore, 9d also showed biometal chelating abilities, antioxidant activity, anti-neuroinflammatory activities and appropriate BBB permeability. These multifunctional properties highlight 9d as promising candidate for further studies directed to the development of novel drugs against AD.
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Affiliation(s)
- Qing Song
- Department of Medicinal Chemistry, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, PR China
| | - Yan Li
- Department of Medicinal Chemistry, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, PR China
| | - Zhongcheng Cao
- Department of Medicinal Chemistry, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, PR China
| | - Hongyan Liu
- Department of Medicinal Chemistry, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, PR China
| | - Chaoquan Tian
- Department of Medicinal Chemistry, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, PR China
| | - Ziyi Yang
- Department of Medicinal Chemistry, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, PR China
| | - Xiaoming Qiang
- Department of Medicinal Chemistry, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, PR China
| | - Zhenghuai Tan
- Institute of Traditional Chinese Medicine Pharmacology and Toxicology, Sichuan Academy of Chinese Medicine Sciences, Chengdu 610041, PR China
| | - Yong Deng
- Department of Medicinal Chemistry, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, PR China.
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9
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Kumar K, Kumar A, Keegan RM, Deshmukh R. Recent advances in the neurobiology and neuropharmacology of Alzheimer’s disease. Biomed Pharmacother 2018; 98:297-307. [DOI: 10.1016/j.biopha.2017.12.053] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 12/03/2017] [Accepted: 12/13/2017] [Indexed: 01/24/2023] Open
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10
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Forest KH, Alfulaij N, Arora K, Taketa R, Sherrin T, Todorovic C, Lawrence JLM, Yoshikawa GT, Ng HL, Hruby VJ, Nichols RA. Protection against β-amyloid neurotoxicity by a non-toxic endogenous N-terminal β-amyloid fragment and its active hexapeptide core sequence. J Neurochem 2017; 144:201-217. [PMID: 29164616 DOI: 10.1111/jnc.14257] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 11/01/2017] [Accepted: 11/07/2017] [Indexed: 11/28/2022]
Abstract
High levels (μM) of beta amyloid (Aβ) oligomers are known to trigger neurotoxic effects, leading to synaptic impairment, behavioral deficits, and apoptotic cell death. The hydrophobic C-terminal domain of Aβ, together with sequences critical for oligomer formation, is essential for this neurotoxicity. However, Aβ at low levels (pM-nM) has been shown to function as a positive neuromodulator and this activity resides in the hydrophilic N-terminal domain of Aβ. An N-terminal Aβ fragment (1-15/16), found in cerebrospinal fluid, was also shown to be a highly active neuromodulator and to reverse Aβ-induced impairments of long-term potentiation. Here, we show the impact of this N-terminal Aβ fragment and a shorter hexapeptide core sequence in the Aβ fragment (Aβcore: 10-15) to protect or reverse Aβ-induced neuronal toxicity, fear memory deficits and apoptotic death. The neuroprotective effects of the N-terminal Aβ fragment and Aβcore on Aβ-induced changes in mitochondrial function, oxidative stress, and apoptotic neuronal death were demonstrated via mitochondrial membrane potential, live reactive oxygen species, DNA fragmentation and cell survival assays using a model neuroblastoma cell line (differentiated NG108-15) and mouse hippocampal neuron cultures. The protective action of the N-terminal Aβ fragment and Aβcore against spatial memory processing deficits in amyloid precursor protein/PSEN1 (5XFAD) mice was demonstrated in contextual fear conditioning. Stabilized derivatives of the N-terminal Aβcore were also shown to be fully protective against Aβ-triggered oxidative stress. Together, these findings indicate an endogenous neuroprotective role for the N-terminal Aβ fragment, while active stabilized N-terminal Aβcore derivatives offer the potential for therapeutic application.
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Affiliation(s)
- Kelly H Forest
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
| | - Naghum Alfulaij
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
| | - Komal Arora
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
| | - Ruth Taketa
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
| | - Tessi Sherrin
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
| | - Cedomir Todorovic
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
| | - James L M Lawrence
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
| | - Gene T Yoshikawa
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
| | - Ho-Leung Ng
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
| | - Victor J Hruby
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, USA
| | - Robert A Nichols
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
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11
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Mukundan V, Maksoudian C, Vogel MC, Chehade I, Katsiotis MS, Alhassan SM, Magzoub M. Cytotoxicity of prion protein-derived cell-penetrating peptides is modulated by pH but independent of amyloid formation. Arch Biochem Biophys 2016; 613:31-42. [PMID: 27818203 DOI: 10.1016/j.abb.2016.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Revised: 10/30/2016] [Accepted: 11/02/2016] [Indexed: 11/25/2022]
Abstract
Prion diseases are associated with conversion of cellular prion protein (PrPC) into an abnormally folded and infectious scrapie isoform (PrPSc). We previously showed that peptides derived from the unprocessed N-termini of mouse and bovine prion proteins, mPrP1-28 and bPrP1-30, function as cell-penetrating peptides (CPPs), and destabilize model membrane systems, which could explain the infectivity and toxicity of prion diseases. However, subsequent studies revealed that treatment with mPrP1-28 or bPrP1-30 significantly reduce PrPSc levels in prion-infected cells. To explain these seemingly contradictory results, we correlated the aggregation, membrane perturbation and cytotoxicity of the peptides with their cellular uptake and intracellular localization. Although the peptides have a similar primary sequence, mPrP1-28 is amyloidogenic, whereas bPrP1-30 forms smaller oligomeric or non-fibrillar aggregates. Surprisingly, bPrP1-30 induces much higher cytotoxicity than mPrP1-28, indicating that amyloid formation and toxicity are independent. The toxicity is correlated with prolonged residence at the plasma membrane and membrane perturbation. Both ordered aggregation and toxicity of the peptides are inhibited by low pH. Under non-toxic conditions, the peptides are internalized by lipid-raft dependent macropinocytosis and localize to acidic lysosomal compartments. Our results shed light on the antiprion mechanism of the prion protein-derived CPPs and identify a potential site for PrPSc formation.
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Affiliation(s)
- Vineeth Mukundan
- Biology Program, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Christy Maksoudian
- Biology Program, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Maria C Vogel
- Biology Program, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Ibrahim Chehade
- Biology Program, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Marios S Katsiotis
- Department of Chemical Engineering, The Petroleum Institute, Abu Dhabi, United Arab Emirates
| | - Saeed M Alhassan
- Department of Chemical Engineering, The Petroleum Institute, Abu Dhabi, United Arab Emirates
| | - Mazin Magzoub
- Biology Program, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates.
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12
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Contribution of α4β2 nAChR in nicotine-induced intracellular calcium response and excitability of MSDB neurons. Brain Res 2015; 1592:1-10. [PMID: 25451094 DOI: 10.1016/j.brainres.2014.10.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 10/05/2014] [Accepted: 10/13/2014] [Indexed: 01/07/2023]
Abstract
The neurons of medial septal diagonal band of broca (MSDB) project to hippocampus and play an important role in MSDB-hippocampal synaptic transmission, plasticity and network oscillation. Nicotinic acetylcholine receptor (nAChR) subunits, α4β2 and α7 nAChRs, are expressed in MSDB neurons and permeable to calcium ions, which may modulate the function of MSDB neurons. The aims of this study are to determine the roles of selective nAChR activation on the calcium responses and membrane currents in MSDB neurons. Our results showed that nicotine increased calcium responses in the majority of MSDB neurons, pre-treatment of MSDB slices with a α4β2 nAChR antagonist, DhβE but not a α7 nAChR antagonist, MLA prevented nicotine-induced calcium responses. The whole cell patch clamp recordings showed that nicotine-induced inward current and acetylcholine (ACh) induced-firing activity can be largely reduced or prevented by DhβE in MSDB neurons. Surprisingly, post-treatment of α4β2 or α7 nAChR antagonists failed to block nicotine׳s role, they increased calcium responses instead. Application of calcium chelator EGTA reduced calcium responses in all neurons tested. These results suggest that there was a subtype specific modulation of nAChRs on calcium signaling and membrane currents in MSDB neurons and nAChR antagonists were also able to induce calcium responses involving a distinct mechanism.
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13
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Arora K, Cheng J, Nichols RA. Nicotinic Acetylcholine Receptors Sensitize a MAPK-linked Toxicity Pathway on Prolonged Exposure to β-Amyloid. J Biol Chem 2015; 290:21409-20. [PMID: 26139609 DOI: 10.1074/jbc.m114.634162] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Indexed: 11/06/2022] Open
Abstract
Among putative downstream synaptic targets of β-amyloid (Aβ) are signaling molecules involved in synaptic function, memory formation and cognition, such as the MAP kinases, MKPs, CaMKII, CREB, Fyn, and Tau. Here, we assessed the activation and interaction of signaling pathways upon prolonged exposure to Aβ in model nerve cells expressing nicotinic acetylcholine receptors (nAChRs). Our goal was to characterize the steps underlying sensitization of the nerve cells to neurotoxicity when Aβ-target receptors are present. Of particular focus was the connection of the activated signaling molecules to oxidative stress. Differentiated neuroblastoma cells expressing mouse α4β2-nAChRs were exposed to Aβ1-42 for intervals from 30 min to 3 days. The cells and cell-derived protein extracts were then probed for activation of signaling pathway molecules (ERK, JNK, CaMKII, CREB, MARCKS, Fyn, tau). Our results show substantial, progressive activation of ERK in response to nanomolar Aβ exposure, starting at the earliest time point. Increased ERK activation was followed by JNK activation as well as an increased expression of PHF-tau, paralleled by increased levels of reactive oxygen species (ROS). The impact of prolonged Aβ on the levels of pERK, pJNK, and ROS was attenuated by MEK-selective and JNK-selective inhibitors. In addition, the MEK inhibitor as well as a JNK inhibitor attenuated Aβ-induced nuclear fragmentation, which followed the changes in ROS levels. These results demonstrate that the presence of nAChRs sensitizes neurons to the neurotoxic action of Aβ through the timed activation of discrete intracellular signaling molecules, suggesting pathways involved in the early stages of Alzheimer disease.
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Affiliation(s)
- Komal Arora
- From the Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii 96813
| | - Justin Cheng
- From the Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii 96813
| | - Robert A Nichols
- From the Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu, Hawaii 96813
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14
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Berry MJ, Astern J, Bellinger F, Brampton C, Cann R, Gerschenson M, Haymer D, James NG, Jameson DM, LeSaux O, Hoffmann PR, Nichols R, Pitts M, Seale L, Seifried S, Stokes AJ, Todorovic C. Medical school hotline: the research mission of the cell and molecular biology department and program at the john a. Burns school of medicine. HAWAI'I JOURNAL OF MEDICINE & PUBLIC HEALTH : A JOURNAL OF ASIA PACIFIC MEDICINE & PUBLIC HEALTH 2015; 74:150-3. [PMID: 25954603 PMCID: PMC4407459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Affiliation(s)
- Marla J Berry
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Joshua Astern
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Frederick Bellinger
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Christopher Brampton
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Rebecca Cann
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Mariana Gerschenson
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - David Haymer
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Nicholas G James
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - David M Jameson
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Olivier LeSaux
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Peter R Hoffmann
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Robert Nichols
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Matthew Pitts
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Lucia Seale
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Steven Seifried
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Alexander J Stokes
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
| | - Cedomir Todorovic
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Manoa, Honolulu HI
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15
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Yang L, Li C, Chen X, Wang J, Gao S, Yang L, Zhao Y, Wang H, Du Y. Evaluation of spinal cord motor function in Alzheimer's disease using electrophysiological techniques indicates association of acetylcholine receptors with the disease. Int J Clin Exp Med 2014; 7:5643-5649. [PMID: 25664084 PMCID: PMC4307531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 12/08/2014] [Indexed: 06/04/2023]
Abstract
AIMS This study is to evaluate the spinal cord motor function in patients with Alzheimer's disease (AD). METHODS In this study, 40 patients were diagnosed to have AD. The stages of dementia were evaluated using Mini Mental State Examination and Activity of Daily Living scale. According to the levels of movement disturbances, the patient group was further divided into dyskinesia subgroup (14 cases) and non-dyskinesia subgroup (26 cases). In addition, 45 age-matched healthy volunteers were included into the control group. Transcranial magnetic stimulation was used to evaluate motor function in the whole motor conduction pathway from motor cortex to target muscles. Electrophysiological studies were used to analyze the pyramidal tract and anterior horn neurons of the spinal cord. RESULTS The mean duration of F waves was prolonged, while no significant differences were found between AD patients and control subjects in parameters such as spinal cord motor conduction velocity, amplitude of motor-evoked potential, F-wave persistence, minimal latency of F-waves and maximal amplitude of F-waves. These data indicated that the excitability of the spinal cord was increased, and the number and function of pyramidal tract and anterior horn cells were integral. CONCLUSIONS The primary mechanism of AD is probably associated with acetylcholine receptors that may participate in the formation of senile plaques and neurofibrillary tangles. These findings may provide new therapeutic targets for the treatment of AD.
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Affiliation(s)
- Li Yang
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University Jinan City, Shandong Province, P. R. China
| | - Chunxia Li
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University Jinan City, Shandong Province, P. R. China
| | - Xiuying Chen
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University Jinan City, Shandong Province, P. R. China
| | - Jie Wang
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University Jinan City, Shandong Province, P. R. China
| | - Shanshan Gao
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University Jinan City, Shandong Province, P. R. China
| | - Liling Yang
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University Jinan City, Shandong Province, P. R. China
| | - Yunxia Zhao
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University Jinan City, Shandong Province, P. R. China
| | - Hua Wang
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University Jinan City, Shandong Province, P. R. China
| | - Yifeng Du
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University Jinan City, Shandong Province, P. R. China
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16
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Lombardo S, Maskos U. Role of the nicotinic acetylcholine receptor in Alzheimer's disease pathology and treatment. Neuropharmacology 2014; 96:255-62. [PMID: 25514383 DOI: 10.1016/j.neuropharm.2014.11.018] [Citation(s) in RCA: 174] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 11/11/2014] [Accepted: 11/24/2014] [Indexed: 11/26/2022]
Abstract
Alzheimer's Disease (AD) is the major form of senile dementia, characterized by neuronal loss, extracellular deposits, and neurofibrillary tangles. It is accompanied by a loss of cholinergic tone, and acetylcholine (ACh) levels in the brain, which were hypothesized to be responsible for the cognitive decline observed in AD. Current medication is restricted to enhancing cholinergic signalling for symptomatic treatment of AD patients. The nicotinic acetylcholine receptor family (nAChR) and the muscarinic acetylcholine receptor family (mAChR) are the target of ACh in the brain. Both families of receptors are affected in AD. It was demonstrated that amyloid beta (Aβ) interacts with nAChRs. Here we discuss how Aβ activates or inhibits nAChRs, and how this interaction contributes to AD pathology. We will discuss the potential role of nAChRs as therapeutic targets. This article is part of the Special Issue entitled 'The Nicotinic Acetylcholine Receptor: From Molecular Biology to Cognition'.
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Affiliation(s)
- Sylvia Lombardo
- Département de Neuroscience, Institut Pasteur, Unité Neurobiologie Intégrative des Systèmes Cholinergiques, Paris Cedex 15, France; CNRS, UMR 3571, Paris, France.
| | - Uwe Maskos
- Département de Neuroscience, Institut Pasteur, Unité Neurobiologie Intégrative des Systèmes Cholinergiques, Paris Cedex 15, France; CNRS, UMR 3571, Paris, France
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17
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Cannabinoid receptor CB1 is involved in nicotine-induced protection against Aβ1-42 neurotoxicity in HT22 cells. J Mol Neurosci 2014; 55:778-87. [PMID: 25262246 DOI: 10.1007/s12031-014-0422-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 09/08/2014] [Indexed: 10/24/2022]
Abstract
Emerging evidences suggest that nicotine exerts a neuroprotective effect on Alzheimer's disease (AD), yet the precise mechanism is not fully elucidated. Here, HT22 cells were exposed to amyloid beta protein fragment (Aβ)1-42 to mimic the pathological process of neuron in AD. We hypothesized that cannabinoid receptor CB1 is involved in the nicotine-induced neuroprotection against Aβ1-42 injury in HT22 cells. CB1 expression in HT22 cells was investigated by immunocytochemistry and Western blot. The injury of HT22 cells was evaluated by cellular morphology, cell viability, and lactate dehydrogenase (LDH) release. The apoptosis of HT22 cells was assessed by flow cytometry and expressions of Bcl-2 and Bax. The results demonstrated that nicotine markedly upregulated CB1 expression, increased cell viability, ameliorated cellular morphology, decreased LDH release, and reduced the apoptotic rate of HT22 cells exposed to Aβ1-42 for 24 h, while the blockade of CB1 or the inhibition of protein kinase C (PKC) partially reversed the neuroprotection. Furthermore, the blockade of CB1 reversed nicotine-induced PKC activation in HT22 cells exposed to Aβ1-42. These results suggest that CB1 is involved in the nicotine-induced neuroprotection against Aβ1-42 neurotoxicity, and the neuroprotection may be dependent on the activation of PKC.
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18
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Zhao W, Luo C, Wang J, Gong J, Li B, Gong Y, Wang J, Wang H. 3-N-butylphthalide improves neuronal morphology after chronic cerebral ischemia. Neural Regen Res 2014; 9:719-26. [PMID: 25206879 PMCID: PMC4146270 DOI: 10.4103/1673-5374.131576] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2014] [Indexed: 11/06/2022] Open
Abstract
3-N-butylphthalide is an effective drug for acute ischemic stroke. However, its effects on chronic cerebral ischemia-induced neuronal injury remain poorly understood. Therefore, this study ligated bilateral carotid arteries in 15-month-old rats to simulate chronic cerebral ischemia in aged humans. Aged rats were then intragastrically administered 3-n-butylphthalide. 3-N-butylphthalide administration improved the neuronal morphology in the cerebral cortex and hippocampus of rats with chronic cerebral ischemia, increased choline acetyltransferase activity, and decreased malondialdehyde and amyloid beta levels, and greatly improved cognitive function. These findings suggest that 3-n-butylphthalide alleviates oxidative stress caused by chronic cerebral ischemia, improves cholinergic function, and inhibits amyloid beta accumulation, thereby improving cerebral neuronal injury and cognitive deficits.
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Affiliation(s)
- Wanhong Zhao
- Institute of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei Province, China
| | - Chao Luo
- Institute of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei Province, China
| | - Jue Wang
- Institute of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei Province, China
| | - Jian Gong
- Institute of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei Province, China
| | - Bin Li
- Institute of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei Province, China
| | - Yingxia Gong
- Institute of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei Province, China
| | - Jun Wang
- Institute of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei Province, China
| | - Hanqin Wang
- Institute of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei Province, China
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19
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Morley WA, Seneff S. Diminished brain resilience syndrome: A modern day neurological pathology of increased susceptibility to mild brain trauma, concussion, and downstream neurodegeneration. Surg Neurol Int 2014; 5:97. [PMID: 25024897 PMCID: PMC4093745 DOI: 10.4103/2152-7806.134731] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 03/31/2014] [Indexed: 12/11/2022] Open
Abstract
The number of sports-related concussions has been steadily rising in recent years. Diminished brain resilience syndrome is a term coined by the lead author to describe a particular physiological state of nutrient functional deficiency and disrupted homeostatic mechanisms leading to increased susceptibility to previously considered innocuous concussion. We discuss how modern day environmental toxicant exposure, along with major changes in our food supply and lifestyle practices, profoundly reduce the bioavailability of neuro-critical nutrients such that the normal processes of homeostatic balance and resilience are no longer functional. Their diminished capacity triggers physiological and biochemical 'work around' processes that result in undesirable downstream consequences. Exposure to certain environmental chemicals, particularly glyphosate, the active ingredient in the herbicide, Roundup(®), may disrupt the body's innate switching mechanism, which normally turns off the immune response to brain injury once danger has been removed. Deficiencies in serotonin, due to disruption of the shikimate pathway, may lead to impaired melatonin supply, which reduces the resiliency of the brain through reduced antioxidant capacity and alterations in the cerebrospinal fluid, reducing critical protective buffering mechanisms in impact trauma. Depletion of certain rare minerals, overuse of sunscreen and/or overprotection from sun exposure, as well as overindulgence in heavily processed, nutrient deficient foods, further compromise the brain's resilience. Modifications to lifestyle practices, if widely implemented, could significantly reduce this trend of neurological damage.
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Affiliation(s)
| | - Stephanie Seneff
- Spoken Language Systems Group, Computer Science and Artificial Intelligence Laboratory, MIT, Cambridge MA 02139, USA
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20
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Huh E, Kim HG, Park H, Kang MS, Lee B, Oh MS. Houttuynia cordata Improves Cognitive Deficits in Cholinergic Dysfunction Alzheimer's Disease-Like Models. Biomol Ther (Seoul) 2014; 22:176-83. [PMID: 25009697 PMCID: PMC4060079 DOI: 10.4062/biomolther.2014.040] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 04/13/2014] [Accepted: 04/15/2014] [Indexed: 11/05/2022] Open
Abstract
Cognitive impairment is a result of dementia of diverse causes, such as cholinergic dysfunction and Alzheimer's disease (AD). Houttuynia cordata Thunb. (Saururaceae) has long been used as a traditional herbal medicine. It has biological activities including protective effects against amyloid beta (Aβ) toxicity, via regulation of calcium homeostasis, in rat hippocampal cells. To extend previous reports, we investigated the effects of water extracts of H. cordata herb (HCW) on tauopathies, also involving calcium influx. We then confirmed the effects of HCW in improving memory impairment and neuronal damage in mice with Aβ-induced neurotoxicity. We also investigated the effects of HCW against scopolamine-induced cholinergic dysfunction in mice. In primary neuronal cells, HCW inhibited the phosphorylation of tau by regulating p25/p35 expression in Aβ-induced neurotoxicity. In mice with Aβ-induced neurotoxicity, HCW improved cognitive impairment, as assessed with behavioral tasks, such as novel object recognition, Y-maze, and passive avoidance tasks. HCW also inhibited the degeneration of neurons in the CA3 region of the hippocampus in Aβ-induced neurotoxicity. Moreover, HCW, which had an IC50 value of 79.7 μg/ml for acetylcholinesterase inhibition, ameliorated scopolamine-induced cognitive impairment significantly in Y-maze and passive avoidance tasks. These results indicate that HCW improved cognitive impairment, due to cholinergic dysfunction, with inhibitory effects against tauopathies and cholinergic antagonists, suggesting that HCW may be an interesting candidate to investigate for the treatment of AD.
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Affiliation(s)
- Eugene Huh
- College of Korean Medicine, Kyung Hee University
| | - Hyo Geun Kim
- College of Pharmacy and Kyung Hee East-West Pharmaceutical Research Institute, Kyung Hee University
- Department of Life and Nanopharmaceutical Science, Graduate School, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - Hanbyeol Park
- Department of Life and Nanopharmaceutical Science, Graduate School, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - Min Seo Kang
- College of Pharmacy and Kyung Hee East-West Pharmaceutical Research Institute, Kyung Hee University
| | - Bongyong Lee
- College of Pharmacy and Kyung Hee East-West Pharmaceutical Research Institute, Kyung Hee University
| | - Myung Sook Oh
- College of Pharmacy and Kyung Hee East-West Pharmaceutical Research Institute, Kyung Hee University
- Department of Life and Nanopharmaceutical Science, Graduate School, Kyung Hee University, Seoul 130-701, Republic of Korea
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21
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Nomura K, Lee M, Banks C, Lee G, Morris BJ. An ASK1-p38 signalling pathway mediates hydrogen peroxide-induced toxicity in NG108-15 neuronal cells. Neurosci Lett 2013; 549:163-7. [PMID: 23742763 DOI: 10.1016/j.neulet.2013.05.045] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 05/22/2013] [Accepted: 05/23/2013] [Indexed: 12/01/2022]
Abstract
Reactive oxygen species (ROS) are believed to be involved in many forms of neurodegeneration, including ischaemic infarct damage and Alzheimer's disease. Despite the known involvement of p38 and JNK MAP kinases in mediating apoptosis and cell death in a variety of cell types, the details of the signalling pathways activated in neuronal cells by ROS are poorly characterised. Recently TAK1 (MAP3K7), a kinase upstream of JNK and p38, has attracted attention as a possible mediator of ischaemic cell death. This study tested the hypothesis that hydrogen peroxide (H2O2), which produces ROS, induces apoptosis in the NG108-15 neuronal cell line via activation of either TAK1 or the related kinase ASK1 (MAP3K5). H2O2 caused a concentration-dependent reduction in cell viability associated with caspase 3 activation. Loss of cell viability was inhibited by a selective caspase 3 inhibitor, and by the p38 inhibitor SB203580, but was not affected by the JNK inhibitor SP600125. The selective TAK1 inhibitor 5Z-7-oxozeaenol (5Z-7) exacerbated the loss of cell viability, whereas the ASK1 inhibitor NQDI-1 completely prevented caspase activation and cell death. These results show that pharmacological inhibition of ASK1 is neuroprotective, implicating an ASK1-p38 signalling pathway in ROS-induced apoptosis in neurones. The results also imply that the role of TAK1 may be neuroprotective rather than pro-degenerative.
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Affiliation(s)
- Koji Nomura
- Institute of Neuroscience and Psychology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
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