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Zhong M, Xu QQ, Hu Z, Yang W, Lin ZX, Xian YF. Tianma-Gouteng pair ameliorates the cognitive deficits on two transgenic mouse models of Alzheimer's disease. JOURNAL OF ETHNOPHARMACOLOGY 2024; 328:118113. [PMID: 38548119 DOI: 10.1016/j.jep.2024.118113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/21/2024] [Accepted: 03/25/2024] [Indexed: 04/02/2024]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Alzheimer's disease (AD) is a progressive neurodegenerative disease. Tianma-Gouteng Pair (TGP), commonly prescribed as a pair-herbs, can be found in many Chinese medicine formulae to treat brain diseases. However, the neuroprotective effects and molecular mechanisms of TGP remained unexplored. AIM OF THE STUDY This study investigated the difference between the TgCRND8 and 5 × FAD transgenic mice, the anti-AD effects of TGP, and underlying molecular mechanisms of TGP against AD through the two mouse models. METHODS Briefly, three-month-old TgCRND8 and 5 × FAD mice were orally administered with TGP for 4 and 6 months, respectively. Behavioral tests were carried out to determine the neuropsychological functions. Moreover, immunofluorescence and western blotting assays were undertaken to reveal the molecular mechanisms of TGP. RESULTS Although TgCRND8 and 5 × FAD mice had different beta-amyloid (Aβ) burdens, neuroinflammation status, and cognition impairments, TGP exerted neuroprotective effects against AD in the two models. In detail, behavioral tests revealed that TGP treatment markedly ameliorated the anxiety-like behavior, attenuated the recognition memory deficits, and increased the spatial learning ability as well as the reference memory of TgCRND8 and 5 × FAD mice. Moreover, TGP treatment could regulate the beta-amyloid precursor protein (APP) processing by inhibiting the Aβ production enzymes such as β- and γ-secretases and activating Aβ degrading enzyme to reduce Aβ accumulation. In addition, TGP reduced the Aβ42 level, the ratio of Aβ42/Αβ40, Aβ accumulation, and tau hyperphosphorylation in both the 5 × FAD and TgCRND8 mouse models. Furthermore, TGP ameliorated neuroinflammation by decreasing the densities of activated microglia and astrocytes, and inhibiting the production of inflammatory cytokines. TGP upregulated the SIRT1 and AMPK, and downregulated sterol response element binding protein 2 (SREBP2) in the brain of TgCRND8 mice and deactivation of the EPhA4 and c-Abl in the brain tissues of 5 × FAD mice. CONCLUSION Our experiments for the first time revealed the neuroprotective effects and molecular mechanism of TGP on 5 × FAD and TgCRND8 transgenic mouse models of different AD stages. TGP decreased the level of Aβ aggregates, improved the tauopathy, and reduced the neuroinflammation by regulation of the SIRT1/AMPK/SREBP2 axis and deactivation of EPhA4/c-Abl signaling pathway in the brains of TgCRND8 and 5 × FAD mice, respectively. All these findings unequivocally confirmed that the TGP would be promising in developing into an anti-AD therapeutic pharmaceutical.
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Affiliation(s)
- Mei Zhong
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, PR China
| | - Qing-Qing Xu
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, PR China
| | - Zhen Hu
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, PR China
| | - Wen Yang
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, PR China
| | - Zhi-Xiu Lin
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, PR China; Hong Kong Institute of Integrative Medicine, The Chinese University of Hong Kong, Hong Kong, Shatin, N.T., Hong Kong SAR, PR China; Li Dak Sum Yip Yio Chin R&D Centre for Chinese Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, PR China.
| | - Yan-Fang Xian
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, PR China.
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Poppell M, Hammel G, Ren Y. Immune Regulatory Functions of Macrophages and Microglia in Central Nervous System Diseases. Int J Mol Sci 2023; 24:5925. [PMID: 36982999 PMCID: PMC10059890 DOI: 10.3390/ijms24065925] [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: 01/31/2023] [Revised: 03/08/2023] [Accepted: 03/14/2023] [Indexed: 03/30/2023] Open
Abstract
Macrophages can be characterized as a very multifunctional cell type with a spectrum of phenotypes and functions being observed spatially and temporally in various disease states. Ample studies have now demonstrated a possible causal link between macrophage activation and the development of autoimmune disorders. How these cells may be contributing to the adaptive immune response and potentially perpetuating the progression of neurodegenerative diseases and neural injuries is not fully understood. Within this review, we hope to illustrate the role that macrophages and microglia play as initiators of adaptive immune response in various CNS diseases by offering evidence of: (1) the types of immune responses and the processes of antigen presentation in each disease, (2) receptors involved in macrophage/microglial phagocytosis of disease-related cell debris or molecules, and, finally, (3) the implications of macrophages/microglia on the pathogenesis of the diseases.
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Affiliation(s)
| | | | - Yi Ren
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL 32306, USA
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Pick E. In memoriam: Filippo Rossi (1926-2022). J Leukoc Biol 2023; 113:231-235. [PMID: 36801947 DOI: 10.1093/jleuko/qiad005] [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: 12/16/2022] [Indexed: 01/28/2023] Open
Abstract
Description of the scientific life of Filippo Rossi, who died in October 2022.
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Affiliation(s)
- Edgar Pick
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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4
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Bellavite P. Neuroprotective Potentials of Flavonoids: Experimental Studies and Mechanisms of Action. Antioxidants (Basel) 2023; 12:antiox12020280. [PMID: 36829840 PMCID: PMC9951959 DOI: 10.3390/antiox12020280] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 01/31/2023] Open
Abstract
Neurological and neurodegenerative diseases, particularly those related to aging, are on the rise, but drug therapies are rarely curative. Functional disorders and the organic degeneration of nervous tissue often have complex causes, in which phenomena of oxidative stress, inflammation and cytotoxicity are intertwined. For these reasons, the search for natural substances that can slow down or counteract these pathologies has increased rapidly over the last two decades. In this paper, studies on the neuroprotective effects of flavonoids (especially the two most widely used, hesperidin and quercetin) on animal models of depression, neurotoxicity, Alzheimer's disease (AD) and Parkinson's disease are reviewed. The literature on these topics amounts to a few hundred publications on in vitro and in vivo models (notably in rodents) and provides us with a very detailed picture of the action mechanisms and targets of these substances. These include the decrease in enzymes that produce reactive oxygen and ferroptosis, the inhibition of mono-amine oxidases, the stimulation of the Nrf2/ARE system, the induction of brain-derived neurotrophic factor production and, in the case of AD, the prevention of amyloid-beta aggregation. The inhibition of neuroinflammatory processes has been documented as a decrease in cytokine formation (mainly TNF-alpha and IL-1beta) by microglia and astrocytes, by modulating a number of regulatory proteins such as Nf-kB and NLRP3/inflammasome. Although clinical trials on humans are still scarce, preclinical studies allow us to consider hesperidin, quercetin, and other flavonoids as very interesting and safe dietary molecules to be further investigated as complementary treatments in order to prevent neurodegenerative diseases or to moderate their deleterious effects.
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Huang Z. A Function of Amyloid-β in Mediating Activity-Dependent Axon/Synapse Competition May Unify Its Roles in Brain Physiology and Pathology. J Alzheimers Dis 2023; 92:29-57. [PMID: 36710681 PMCID: PMC10023438 DOI: 10.3233/jad-221042] [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: 01/28/2023]
Abstract
Amyloid-β protein precursor (AβPP) gives rise to amyloid-β (Aβ), a peptide at the center of Alzheimer's disease (AD). AβPP, however, is also an ancient molecule dating back in evolution to some of the earliest forms of metazoans. This suggests a possible ancestral function that may have been obscured by those that evolve later. Based on literature from the functions of Aβ/AβPP in nervous system development, plasticity, and disease, to those of anti-microbial peptides (AMPs) in bacterial competition as well as mechanisms of cell competition uncovered first by Drosophila genetics, I propose that Aβ/AβPP may be part of an ancient mechanism employed in cell competition, which is subsequently co-opted during evolution for the regulation of activity-dependent neural circuit development and plasticity. This hypothesis is supported by foremost the high similarities of Aβ to AMPs, both of which possess unique, opposite (i.e., trophic versus toxic) activities as monomers and oligomers. A large body of data further suggests that the different Aβ oligomeric isoforms may serve as the protective and punishment signals long predicted to mediate activity-dependent axonal/synaptic competition in the developing nervous system and that the imbalance in their opposite regulation of innate immune and glial cells in the brain may ultimately underpin AD pathogenesis. This hypothesis can not only explain the diverse roles observed of Aβ and AβPP family molecules, but also provide a conceptual framework that can unify current hypotheses on AD. Furthermore, it may explain major clinical observations not accounted for and identify approaches for overcoming shortfalls in AD animal modeling.
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Affiliation(s)
- Zhen Huang
- Departments of Neuroscience and Neurology, University of Wisconsin-Madison, Madison, WI, USA
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Pontrello CG, McWhirt JM, Glabe CG, Brewer GJ. Age-Related Oxidative Redox and Metabolic Changes Precede Intraneuronal Amyloid-β Accumulation and Plaque Deposition in a Transgenic Alzheimer's Disease Mouse Model. J Alzheimers Dis 2022; 90:1501-1521. [PMID: 36278355 PMCID: PMC9789488 DOI: 10.3233/jad-220824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Many identified mechanisms could be upstream of the prominent amyloid-β (Aβ) plaques in Alzheimer's disease (AD). OBJECTIVE To profile the progression of pathology in AD. METHODS We monitored metabolic signaling, redox stress, intraneuronal amyloid-β (iAβ) accumulation, and extracellular plaque deposition in the brains of 3xTg-AD mice across the lifespan. RESULTS Intracellular accumulation of aggregated Aβ in the CA1 pyramidal cells at 9 months preceded extracellular plaques that first presented in the CA1 at 16 months of age. In biochemical assays, brain glutathione (GSH) declined with age in both 3xTg-AD and non-transgenic controls, but the decline was accelerated in 3xTg-AD brains from 2 to 4 months. The decline in GSH correlated exponentially with the rise in iAβ. Integrated metabolic signaling as the ratio of phospho-Akt (pAkt) to total Akt (tAkt) in the PI3kinase and mTOR pathway declined at 6, 9, and 12 months, before rising at 16 and 20 months. These pAkt/tAkt ratios correlated with both iAβ and GSH levels in a U-shaped relationship. Selective vulnerability of age-related AD-genotype-specific pAkt changes was greatest in the CA1 pyramidal cell layer. To demonstrate redox causation, iAβ accumulation was lowered in cultured middle-age adult 3xTg-AD neurons by treatment of the oxidized redox state in the neurons with exogenous cysteine. CONCLUSION The order of pathologic progression in the 3xTg-AD mouse was loss of GSH (oxidative redox shift) followed by a pAkt/tAkt metabolic shift in CA1, iAβ accumulation in CA1, and extracellular Aβ deposition. Upstream targets may prove strategically more effective for therapy before irreversible changes.
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Affiliation(s)
- Crystal G. Pontrello
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, CA, USA,
Department of Biomedical Engineering, University of California Irvine, Irvine, CA, USA
| | - Joshua M. McWhirt
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA, USA
| | - Charles G. Glabe
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, CA, USA,
Center for Neurobiology of Learning and Memory, University of California Irvine, Irvine, CA, USA,
MIND Institute, University of California Irvine, Irvine, CA, USA
| | - Gregory J. Brewer
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA, USA,
Center for Neurobiology of Learning and Memory, University of California Irvine, Irvine, CA, USA,
MIND Institute, University of California Irvine, Irvine, CA, USA,Correspondence to: Gregory J. Brewer, Department of Biomedical Engineering, University of California Irvine, Irvine, CA 92697, USA. Tel.: +1 217 502 4511; E-mail:
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Attanzio A, Restivo I, Tutone M, Tesoriere L, Allegra M, Livrea MA. Redox Properties, Bioactivity and Health Effects of Indicaxanthin, a Bioavailable Phytochemical from Opuntia ficus indica, L.: A Critical Review of Accumulated Evidence and Perspectives. Antioxidants (Basel) 2022; 11:antiox11122364. [PMID: 36552572 PMCID: PMC9774763 DOI: 10.3390/antiox11122364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/16/2022] [Accepted: 11/23/2022] [Indexed: 12/05/2022] Open
Abstract
Phytochemicals from plant foods are considered essential to human health. Known for their role in the adaptation of plants to their environment, these compounds can induce adaptive responses in cells, many of which are directed at maintaining the redox tone. Indicaxanthin is a long-known betalain pigment found in the genus Opuntia of cactus pear and highly concentrated in the edible fruits of O. ficus indica, L. whose bioactivity has been overlooked until recently. This review summarizes studies conducted so far in vitro and in vivo, most of which have been performed in our laboratory. The chemical and physicochemical characteristics of Indicaxanthin are reflected in the molecule's reducing properties and antioxidant effects and help explain its ability to interact with membranes, modulate redox-regulated cellular pathways, and possibly bind to protein molecules. Measurement of bioavailability in volunteers has been key to exploring its bioactivity; amounts consistent with dietary intake, or plasma concentration after dietary consumption of cactus pear fruit, have been used in experimental setups mimicking physiological or pathophysiological conditions, in cells and in animals, finally suggesting pharmacological potential and relevance of Indicaxanthin as a nutraceutical. In reporting experimental results, this review also aimed to raise questions and seek insights for further basic research and health promotion applications.
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Hsieh CJ, Hou C, Zhu Y, Lee JY, Kohli N, Gallagher E, Xu K, Lee H, Li S, McManus MJ, Mach RH. [ 18F]ROStrace detects oxidative stress in vivo and predicts progression of Alzheimer's disease pathology in APP/PS1 mice. EJNMMI Res 2022; 12:43. [PMID: 35895177 PMCID: PMC9329498 DOI: 10.1186/s13550-022-00914-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 07/18/2022] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Oxidative stress is implicated in the pathogenesis of the most common neurodegenerative diseases, such as Alzheimer's disease (AD). However, tracking oxidative stress in the brain has proven difficult and impeded its use as a biomarker. Herein, we investigate the utility of a novel positron emission tomography (PET) tracer, [18F]ROStrace, as a biomarker of oxidative stress throughout the course of AD in the well-established APP/PS1 double-mutant mouse model. PET imaging studies were conducted in wild-type (WT) and APP/PS1 mice at 3 different time points, representing early (5 mo.), middle (10 mo.), and advanced (16 mo.) life (n = 6-12, per sex). Semi-quantitation SUVRs of the plateau phase (40-60 min post-injection; SUVR40-60) of ten brain subregions were designated by the Mirrione atlas and analyzed by Pmod. Statistical parametric mapping (SPM) was used to distinguish brain regions with elevated ROS in APP/PS1 relative to WT in both sexes. The PET studies were validated by ex vivo autoradiography and immunofluorescence with the parent compound, dihydroethidium. RESULTS [18F]ROStrace retention was increased in the APP/PS1 brain compared to age-matched controls by 10 mo. of age (p < 0.0001) and preceded the accumulation of oxidative damage in APP/PS1 neurons at 16 mo. (p < 0.005). [18F]ROStrace retention and oxidative damages were higher and occurred earlier in female APP/PS1 mice as measured by PET (p < 0.001), autoradiography, and immunohistochemistry (p < 0.05). [18F]ROStrace differences emerged midlife, temporally and spatially correlating with increased Aβ burden (r2 = 0.36; p = 0.0003), which was also greatest in the female brain (p < 0.001). CONCLUSIONS [18F]ROStrace identifies increased oxidative stress and neuroinflammation in APP/PS1 female mice, concurrent with increased amyloid burden midlife. Differences in oxidative stress during this crucial time may partially explain the sexual dimorphism in AD. [18F]ROStrace may provide a long-awaited tool to stratify at-risk patients who may benefit from antioxidant therapy prior to irreparable neurodegeneration.
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Affiliation(s)
- Chia-Ju Hsieh
- grid.25879.310000 0004 1936 8972Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Catherine Hou
- grid.25879.310000 0004 1936 8972Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Yi Zhu
- grid.239552.a0000 0001 0680 8770Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA ,grid.239552.a0000 0001 0680 8770Center for Mitochondrial and Epigenomic Medicine, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
| | - Ji Youn Lee
- grid.25879.310000 0004 1936 8972Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Neha Kohli
- grid.239552.a0000 0001 0680 8770Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA ,grid.239552.a0000 0001 0680 8770Center for Mitochondrial and Epigenomic Medicine, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
| | - Evan Gallagher
- grid.25879.310000 0004 1936 8972Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA ,grid.239552.a0000 0001 0680 8770Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA ,grid.239552.a0000 0001 0680 8770Center for Mitochondrial and Epigenomic Medicine, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
| | - Kuiying Xu
- grid.25879.310000 0004 1936 8972Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Hsiaoju Lee
- grid.25879.310000 0004 1936 8972Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Shihong Li
- grid.25879.310000 0004 1936 8972Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Meagan J. McManus
- grid.239552.a0000 0001 0680 8770Department of Anesthesiology and Critical Care Medicine, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA ,grid.239552.a0000 0001 0680 8770Center for Mitochondrial and Epigenomic Medicine, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104 USA
| | - Robert H. Mach
- grid.25879.310000 0004 1936 8972Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
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Barkaway A, Attwell D, Korte N. Immune-vascular mural cell interactions: consequences for immune cell trafficking, cerebral blood flow, and the blood-brain barrier. NEUROPHOTONICS 2022; 9:031914. [PMID: 35581998 PMCID: PMC9107322 DOI: 10.1117/1.nph.9.3.031914] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 04/13/2022] [Indexed: 06/15/2023]
Abstract
Brain barriers are crucial sites for cerebral energy supply, waste removal, immune cell migration, and solute exchange, all of which maintain an appropriate environment for neuronal activity. At the capillary level, where the largest area of brain-vascular interface occurs, pericytes adjust cerebral blood flow (CBF) by regulating capillary diameter and maintain the blood-brain barrier (BBB) by suppressing endothelial cell (EC) transcytosis and inducing tight junction expression between ECs. Pericytes also limit the infiltration of circulating leukocytes into the brain where resident microglia confine brain injury and provide the first line of defence against invading pathogens. Brain "waste" is cleared across the BBB into the blood, phagocytosed by microglia and astrocytes, or removed by the flow of cerebrospinal fluid (CSF) through perivascular routes-a process driven by respiratory motion and the pulsation of the heart, arteriolar smooth muscle, and possibly pericytes. "Dirty" CSF exits the brain and is probably drained around olfactory nerve rootlets and via the dural meningeal lymphatic vessels and possibly the skull bone marrow. The brain is widely regarded as an immune-privileged organ because it is accessible to few antigen-primed leukocytes. Leukocytes enter the brain via the meninges, the BBB, and the blood-CSF barrier. Advances in genetic and imaging tools have revealed that neurological diseases significantly alter immune-brain barrier interactions in at least three ways: (1) the brain's immune-privileged status is compromised when pericytes are lost or lymphatic vessels are dysregulated; (2) immune cells release vasoactive molecules to regulate CBF, modulate arteriole stiffness, and can plug and eliminate capillaries which impairs CBF and possibly waste clearance; and (3) immune-vascular interactions can make the BBB leaky via multiple mechanisms, thus aggravating the influx of undesirable substances and cells. Here, we review developments in these three areas and briefly discuss potential therapeutic avenues for restoring brain barrier functions.
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Affiliation(s)
- Anna Barkaway
- University College London, Department of Neuroscience, Physiology and Pharmacology, London, United Kingdom
| | - David Attwell
- University College London, Department of Neuroscience, Physiology and Pharmacology, London, United Kingdom
| | - Nils Korte
- University College London, Department of Neuroscience, Physiology and Pharmacology, London, United Kingdom
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Shared pathophysiology: Understanding stroke and Alzheimer’s disease. Clin Neurol Neurosurg 2022; 218:107306. [PMID: 35636382 DOI: 10.1016/j.clineuro.2022.107306] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 05/03/2022] [Accepted: 05/19/2022] [Indexed: 12/17/2022]
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Microglia in Alzheimer’s Disease: A Favorable Cellular Target to Ameliorate Alzheimer’s Pathogenesis. Mediators Inflamm 2022; 2022:6052932. [PMID: 35693110 PMCID: PMC9184163 DOI: 10.1155/2022/6052932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 05/09/2022] [Indexed: 11/18/2022] Open
Abstract
Microglial cells serve as molecular sensors of the brain that play a role in physiological and pathological conditions. Under normal physiology, microglia are primarily responsible for regulating central nervous system homeostasis through the phagocytic clearance of redundant protein aggregates, apoptotic cells, damaged neurons, and synapses. Furthermore, microglial cells can promote and mitigate amyloid β phagocytosis and tau phosphorylation. Dysregulation of the microglial programming alters cellular morphology, molecular signaling, and secretory inflammatory molecules that contribute to various neurodegenerative disorders especially Alzheimer’s disease (AD). Furthermore, microglia are considered primary sources of inflammatory molecules and can induce or regulate a broad spectrum of cellular responses. Interestingly, in AD, microglia play a double-edged role in disease progression; for instance, the detrimental microglial effects increase in AD while microglial beneficiary mechanisms are jeopardized. Depending on the disease stages, microglial cells are expressed differently, which may open new avenues for AD therapy. However, the disease-related role of microglial cells and their receptors in the AD brain remain unclear. Therefore, this review represents the role of microglial cells and their involvement in AD pathogenesis.
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Sleep deficiency as a driver of cellular stress and damage in neurological disorders. Sleep Med Rev 2022; 63:101616. [PMID: 35381445 PMCID: PMC9177816 DOI: 10.1016/j.smrv.2022.101616] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 12/23/2022]
Abstract
Neurological disorders encompass an extremely broad range of conditions, including those that present early in development and those that progress slowly or manifest with advanced age. Although these disorders have distinct underlying etiologies, the activation of shared pathways, e.g., integrated stress response (ISR) and the development of shared phenotypes (sleep deficits) may offer clues toward understanding some of the mechanistic underpinnings of neurologic dysfunction. While it is incontrovertibly complex, the relationship between sleep and persistent stress in the brain has broad implications in understanding neurological disorders from development to degeneration. The convergent nature of the ISR could be a common thread linking genetically distinct neurological disorders through the dysregulation of a core cellular homeostasis pathway.
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Wu X, Zeng H, Cai L, Chen G. Role of the Extracellular Traps in Central Nervous System. Front Immunol 2021; 12:783882. [PMID: 34868063 PMCID: PMC8635093 DOI: 10.3389/fimmu.2021.783882] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 10/26/2021] [Indexed: 12/20/2022] Open
Abstract
It has been reported that several immune cells can release chromatin and granular proteins into extracellular space in response to the stimulation, forming extracellular traps (ETs). The cells involved in the extracellular trap formation are recognized including neutropils, macrophages, basophils, eosinophils, and mast cells. With the development of research related to central nervous system, the role of ETs has been valued in neuroinflammation, blood–brain barrier, and other fields. Meanwhile, it has been found that microglial cells as the resident immune cells of the central nervous system can also release ETs, updating the original understanding. This review aims to clarify the role of the ETs in the central nervous system, especially in neuroinflammation and blood–brain barrier.
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Affiliation(s)
- Xinyan Wu
- Department of Neurological Surgery The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Hanhai Zeng
- Department of Neurological Surgery The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Lingxin Cai
- Department of Neurological Surgery The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Gao Chen
- Department of Neurological Surgery The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
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Villegas L, Nørremølle A, Freude K, Vilhardt F. Nicotinamide Adenine Dinucleotide Phosphate Oxidases Are Everywhere in Brain Disease, but Not in Huntington's Disease? Front Aging Neurosci 2021; 13:736734. [PMID: 34803655 PMCID: PMC8602359 DOI: 10.3389/fnagi.2021.736734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 10/08/2021] [Indexed: 11/13/2022] Open
Abstract
Huntington’s disease (HD) is an inherited neurodegenerative disorder characterized by neuronal loss and tissue atrophy mainly in the striatum and cortex. In the early stages of the disease, impairment of neuronal function, synaptic dysfunction and white matter loss precedes neuronal death itself. Relative to other neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease and Amyotrophic Lateral Sclerosis, where the effects of either microglia or NADPH oxidases (NOXs) are recognized as important contributors to disease pathogenesis and progression, there is a pronounced lack of information in HD. This information void contrasts with evidence from human HD patients where blood monocytes and microglia are activated well before HD clinical symptoms (PET scans), and the clear signs of oxidative stress and inflammation in post mortem HD brain. Habitually, NOX activity and oxidative stress in the central nervous system (CNS) are equated with microglia, but research of the last two decades has carved out important roles for NOX enzyme function in neurons. Here, we will convey recent information about the function of NOX enzymes in neurons, and contemplate on putative roles of neuronal NOX in HD. We will focus on NOX-produced reactive oxygen species (ROS) as redox signaling molecules in/among neurons, and the specific roles of NOXs in important processes such as neurogenesis and lineage specification, neurite outgrowth and growth cone dynamics, and synaptic plasticity where NMDAR-dependent signaling, and long-term depression/potentiation are redox-regulated phenomena. HD animal models and induced pluripotent stem cell (iPSC) studies have made it clear that the very same physiological processes are also affected in HD, and we will speculate on possible roles for NOX in the pathogenesis and development of disease. Finally, we also take into account the limited information on microglia in HD and relate this to any contribution of NOX enzymes.
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Affiliation(s)
- Luisana Villegas
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Anne Nørremølle
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Kristine Freude
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Frederik Vilhardt
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
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15
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The Protective Effect of Ubiquinone against the Amyloid Peptide in Endothelial Cells Is Isoprenoid Chain Length-Dependent. Antioxidants (Basel) 2021; 10:antiox10111806. [PMID: 34829677 PMCID: PMC8615161 DOI: 10.3390/antiox10111806] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 12/23/2022] Open
Abstract
Vascular brain pathology constitutes a common feature in neurodegenerative diseases that could underlie their development. Indeed, vascular dysfunction acts synergistically with neurodegenerative changes to exacerbate the cognitive impairment found in Alzheimer’s disease. Different injuries such as hypertension, high glucose, atherosclerosis associated with oxidized low-density lipoprotein or inflammation induce NADPH oxidase activation, overproduction of reactive oxygen species, and apoptosis in endothelial cells. Since it has been shown that pretreatment of cultured endothelial cells with the lipophilic antioxidant coenzyme Q10 (CoQ10) displays a protective effect against the deleterious injuries caused by different agents, this study explores the cytoprotective role of different CoQs homologues against Aβ25–35-induced damage and demonstrates that only pretreatment with CoQ10 protects endothelial brain cells from Aβ25–35-induced damage. Herein, we show that CoQ10 constitutes the most effective ubiquinone in preventing NADPH oxidase activity and reducing both reactive oxygen species generation and the increase in free cytosolic Ca2+ induced by Aβ25–35, ultimately preventing apoptosis and necrosis. The specific cytoprotective effect of CoQ with a side chain of 10 isoprenoid units could be explained by the fact that CoQ10 is the only ubiquinone that significantly reduces the entry of Aβ25–35 into the mitochondria.
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16
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Schmidt C, Schneble-Löhnert N, Lajqi T, Wetzker R, Müller JP, Bauer R. PI3Kγ Mediates Microglial Proliferation and Cell Viability via ROS. Cells 2021; 10:2534. [PMID: 34685514 PMCID: PMC8534080 DOI: 10.3390/cells10102534] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/22/2021] [Accepted: 09/23/2021] [Indexed: 12/14/2022] Open
Abstract
(1) Background: Rapid microglial proliferation contributes to the complex responses of the innate immune system in the brain to various neuroinflammatory stimuli. Here, we investigated the regulatory function of phosphoinositide 3-kinase γ (PI3Kγ) and reactive oxygen species (ROS) for rapid proliferation of murine microglia induced by LPS and ATP. (2) Methods: PI3Kγ knockout mice (PI3Kγ KO), mice expressing catalytically inactive PI3Kγ (PI3Kγ KD) and wild-type mice were assessed for microglial proliferation using an in vivo wound healing assay. Additionally, primary microglia derived from newborn wild-type, PI3Kγ KO and PI3Kγ KD mice were used to analyze PI3Kγ effects on proliferation and cell viability, senescence and cellular and mitochondrial ROS production; the consequences of ROS production for proliferation and cell viability after LPS or ATP stimulation were studied using genetic and pharmacologic approaches. (3) Results: Mice with a loss of lipid kinase activity showed impaired proliferation of microglia. The prerequisite of induced microglial proliferation and cell viability appeared to be PI3Kγ-mediated induction of ROS production. (4) Conclusions: The lipid kinase activity of PI3Kγ plays a crucial role for microglial proliferation and cell viability after acute inflammatory activation.
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Affiliation(s)
- Caroline Schmidt
- Center for Molecular Biomedicine, Institute of Molecular Cell Biology, Jena University Hospital, 07745 Jena, Germany; (C.S.); (N.S.-L.); (J.P.M.)
| | - Nadine Schneble-Löhnert
- Center for Molecular Biomedicine, Institute of Molecular Cell Biology, Jena University Hospital, 07745 Jena, Germany; (C.S.); (N.S.-L.); (J.P.M.)
| | - Trim Lajqi
- Department of Neonatology, Heidelberg University Children’s Hospital, 69120 Heidelberg, Germany;
| | - Reinhard Wetzker
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, 07747 Jena, Germany;
| | - Jörg P. Müller
- Center for Molecular Biomedicine, Institute of Molecular Cell Biology, Jena University Hospital, 07745 Jena, Germany; (C.S.); (N.S.-L.); (J.P.M.)
| | - Reinhard Bauer
- Center for Molecular Biomedicine, Institute of Molecular Cell Biology, Jena University Hospital, 07745 Jena, Germany; (C.S.); (N.S.-L.); (J.P.M.)
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17
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The Role of Neutrophil Extracellular Traps in Central Nervous System Diseases and Prospects for Clinical Application. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:9931742. [PMID: 34336122 PMCID: PMC8294981 DOI: 10.1155/2021/9931742] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Accepted: 07/01/2021] [Indexed: 12/13/2022]
Abstract
Neutrophil extracellular traps (NETs) are complexes of decondensed DNA fibers and antimicrobial peptides that are released by neutrophils and play important roles in many noninfectious diseases, such as cystic fibrosis, systemic lupus erythematosus, diabetes, and cancer. Recently, the formation of NETs has been detected in many central nervous system diseases and is thought to play different roles in the occurrence and development of these diseases. Researchers have detected NETs in acute ischemic stroke thrombi, and these NETs are thought to promote coagulation and thrombosis. NETs in ischemic brain parenchyma were identified as the cause of secondary nerve damage. High levels of NETs were also detected in grade IV glioma tissues, where NETs were involved in the proliferation and invasion of glioma cells by activating a signaling pathway. Extracellular web-like structures have also recently been observed in mice with traumatic brain injury (TBI), and it was hypothesized that NETs contribute to the development of edema after TBI. This article reviews the effect of NETs on multiple diseases that affect the CNS and explores their clinical application prospects.
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18
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Fragoso-Morales LG, Correa-Basurto J, Rosales-Hernández MC. Implication of Nicotinamide Adenine Dinucleotide Phosphate (NADPH) Oxidase and Its Inhibitors in Alzheimer's Disease Murine Models. Antioxidants (Basel) 2021; 10:antiox10020218. [PMID: 33540840 PMCID: PMC7912941 DOI: 10.3390/antiox10020218] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/19/2021] [Accepted: 01/23/2021] [Indexed: 02/06/2023] Open
Abstract
Alzheimer’s disease (AD) is one of the main human dementias around the world which is constantly increasing every year due to several factors (age, genetics, environment, etc.) and there are no prevention or treatment options to cure it. AD is characterized by memory loss associated with oxidative stress (OS) in brain cells (neurons, astrocytes, microglia, etc.). OS can be produced by amyloid beta (Aβ) protein aggregation and its interaction with metals, mitochondrial damage and alterations between antioxidants and oxidant enzymes such as nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. NADPH oxidase produces reactive oxygen species (ROS) and it is overexpressed in AD, producing large amounts of superoxide anions and hydrogen peroxide which damage brain cells and the vasculature. In addition, it has been reported that NADPH oxidase causes an imbalance of pH which could also influence in the amyloid beta (Aβ) production. Therefore, NADPH oxidase had been proposed as a therapeutic target in AD. However, there are no drugs for AD treatment such as an NADPH oxidase inhibitor despite great efforts made to stabilize the ROS production using antioxidant molecules. So, in this work, we will focus our attention on NADPH oxidase (NOX2 and NOX4) in AD as well as in AD models and later discuss the use of NADPH oxidase inhibitor compounds in AD.
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Affiliation(s)
- Leticia Guadalupe Fragoso-Morales
- Laboratorio de Biofísica y Biocatálisis, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón s/n, Mexico City 11340, Mexico;
| | - José Correa-Basurto
- Laboratorio de Diseño y Desarrollo de Nuevos Fármacos e Innovación Biotecnológica, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, Mexico City 11340, Mexico;
| | - Martha Cecilia Rosales-Hernández
- Laboratorio de Biofísica y Biocatálisis, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón s/n, Mexico City 11340, Mexico;
- Correspondence: ; Tel.: +(55)-572-960-00 (ext. 62767 & 62809)
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Sandhu JK, Kulka M. Decoding Mast Cell-Microglia Communication in Neurodegenerative Diseases. Int J Mol Sci 2021; 22:ijms22031093. [PMID: 33499208 PMCID: PMC7865982 DOI: 10.3390/ijms22031093] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/16/2021] [Accepted: 01/17/2021] [Indexed: 12/12/2022] Open
Abstract
Microglia, resident immune cells of the central nervous system (CNS), play a pivotal role in immune surveillance and maintenance of neuronal health. Mast cells are also important resident immune cells of the CNS but they are underappreciated and understudied. Both microglia and mast cells are endowed with an array of signaling receptors that recognize microbes and cellular damage. As cellular sensors and effectors in the CNS, they respond to many CNS perturbations and have been implicated in neuroinflammation and neurodegeneration. Mast cells contain numerous secretory granules packaged with a plethora of readily available and newly synthesized compounds known as 'mast cell mediators'. Mast cells act as 'first responders' to a pathogenic stimuli and respond by degranulation and releasing these mediators into the extracellular milieu. They alert other glial cells, including microglia to initiate neuroinflammatory processes that culminate in the resolution of injury. However, failure to resolve the pathogenic process can lead to persistent activation, release of pro-inflammatory mediators and amplification of neuroinflammatory responses, in turn, resulting in neuronal dysfunction and demise. This review discusses the current understanding of the molecular conversation between mast cells and microglia in orchestrating immune responses during two of the most prevalent neurodegenerative diseases, namely Alzheimer's disease and Parkinson's disease. Here we also survey the potential emerging therapeutic approaches targeting common pathways in mast cells and microglia to extinguish the fire of inflammation.
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Affiliation(s)
- Jagdeep K. Sandhu
- Human Health Therapeutics Research Centre, National Research Council Canada, 1200 Montreal Road, Ottawa, ON K1A 0R6, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5, Canada
- Correspondence: (J.K.S.); (M.K.); Tel.: +1-613-993-5304 (J.K.S.); +1-780-641-1687 (M.K.)
| | - Marianna Kulka
- Nanotechnology Research Centre, National Research Council Canada, 11421 Saskatchewan Drive, Edmonton, AB T6G 2M9, Canada
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2E1, Canada
- Correspondence: (J.K.S.); (M.K.); Tel.: +1-613-993-5304 (J.K.S.); +1-780-641-1687 (M.K.)
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20
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Loeffler DA. Modifiable, Non-Modifiable, and Clinical Factors Associated with Progression of Alzheimer's Disease. J Alzheimers Dis 2021; 80:1-27. [PMID: 33459643 DOI: 10.3233/jad-201182] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
There is an extensive literature relating to factors associated with the development of Alzheimer's disease (AD), but less is known about factors which may contribute to its progression. This review examined the literature with regard to 15 factors which were suggested by PubMed search to be positively associated with the cognitive and/or neuropathological progression of AD. The factors were grouped as potentially modifiable (vascular risk factors, comorbidities, malnutrition, educational level, inflammation, and oxidative stress), non-modifiable (age at clinical onset, family history of dementia, gender, Apolipoprotein E ɛ4, genetic variants, and altered gene regulation), and clinical (baseline cognitive level, neuropsychiatric symptoms, and extrapyramidal signs). Although conflicting results were found for the majority of factors, a positive association was found in nearly all studies which investigated the relationship of six factors to AD progression: malnutrition, genetic variants, altered gene regulation, baseline cognitive level, neuropsychiatric symptoms, and extrapyramidal signs. Whether these or other factors which have been suggested to be associated with AD progression actually influence the rate of decline of AD patients is unclear. Therapeutic approaches which include addressing of modifiable factors associated with AD progression should be considered.
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Affiliation(s)
- David A Loeffler
- Beaumont Research Institute, Department of Neurology, Beaumont Health, Royal Oak, MI, USA
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21
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Danger-Sensing/Patten Recognition Receptors and Neuroinflammation in Alzheimer's Disease. Int J Mol Sci 2020; 21:ijms21239036. [PMID: 33261147 PMCID: PMC7731137 DOI: 10.3390/ijms21239036] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 11/24/2020] [Accepted: 11/25/2020] [Indexed: 02/06/2023] Open
Abstract
Fibrillar aggregates and soluble oligomers of both Amyloid-β peptides (Aβs) and hyperphosphorylated Tau proteins (p-Tau-es), as well as a chronic neuroinflammation are the main drivers causing progressive neuronal losses and dementia in Alzheimer’s disease (AD). However, the underlying pathogenetic mechanisms are still much disputed. Several endogenous neurotoxic ligands, including Aβs, and/or p-Tau-es activate innate immunity-related danger-sensing/pattern recognition receptors (PPRs) thereby advancing AD’s neuroinflammation and progression. The major PRR families involved include scavenger, Toll-like, NOD-like, AIM2-like, RIG-like, and CLEC-2 receptors, plus the calcium-sensing receptor (CaSR). This quite intricate picture stresses the need to identify the pathogenetically topmost Aβ-activated PRR, whose signaling would trigger AD’s three main drivers and their intra-brain spread. In theory, the candidate might belong to any PRR family. However, results of preclinical studies using in vitro nontumorigenic human cortical neurons and astrocytes and in vivo AD-model animals have started converging on the CaSR as the pathogenetically upmost PRR candidate. In fact, the CaSR binds both Ca2+ and Aβs and promotes the spread of both Ca2+ dyshomeostasis and AD’s three main drivers, causing a progressive neurons’ death. Since CaSR’s negative allosteric modulators block all these effects, CaSR’s candidacy for topmost pathogenetic PRR has assumed a growing therapeutic potential worth clinical testing.
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22
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Gamage R, Wagnon I, Rossetti I, Childs R, Niedermayer G, Chesworth R, Gyengesi E. Cholinergic Modulation of Glial Function During Aging and Chronic Neuroinflammation. Front Cell Neurosci 2020; 14:577912. [PMID: 33192323 PMCID: PMC7594524 DOI: 10.3389/fncel.2020.577912] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/07/2020] [Indexed: 12/12/2022] Open
Abstract
Aging is a complex biological process that increases the risk of age-related cognitive degenerative diseases such as dementia, including Alzheimer’s disease (AD), Lewy Body Dementia (LBD), and mild cognitive impairment (MCI). Even non-pathological aging of the brain can involve chronic oxidative and inflammatory stress, which disrupts the communication and balance between the brain and the immune system. There has been an increasingly strong connection found between chronic neuroinflammation and impaired memory, especially in AD. While microglia and astrocytes, the resident immune cells of the central nervous system (CNS), exerting beneficial effects during the acute inflammatory phase, during chronic neuroinflammation they can become more detrimental. Central cholinergic circuits are involved in maintaining normal cognitive function and regulating signaling within the entire cerebral cortex. While neuronal-glial cholinergic signaling is anti-inflammatory and anti-oxidative, central cholinergic neuronal degeneration is implicated in impaired learning, memory sleep regulation, and attention. Although there is evidence of cholinergic involvement in memory, fewer studies have linked the cholinergic anti-inflammatory and anti-oxidant pathways to memory processes during development, normal aging, and disease states. This review will summarize the current knowledge of cholinergic effects on microglia and astroglia, and their role in both anti-inflammatory and anti-oxidant mechanisms, concerning normal aging and chronic neuroinflammation. We provided details on how stimulation of α7 nicotinic acetylcholine (α7nACh) receptors can be neuroprotective by increasing amyloid-β phagocytosis, decreasing inflammation and reducing oxidative stress by promoting the nuclear factor erythroid 2-related factor 2 (Nrf2) pathways and decreasing the release of pro-inflammatory cytokines. There is also evidence for astroglial α7nACh receptor stimulation mediating anti-inflammatory and antioxidant effects by inhibiting the nuclear factor-κB (NF-κB) pathway and activating the Nrf2 pathway respectively. We conclude that targeting cholinergic glial interactions between neurons and glial cells via α7nACh receptors could regulate neuroinflammation and oxidative stress, relevant to the treatment of several neurodegenerative diseases.
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Affiliation(s)
- Rashmi Gamage
- Department of Pharmacology, School of Medicine, Western Sydney University, Penrith, NSW, Australia
| | - Ingrid Wagnon
- Department of Pharmacology, School of Medicine, Western Sydney University, Penrith, NSW, Australia
| | - Ilaria Rossetti
- Department of Pharmacology, School of Medicine, Western Sydney University, Penrith, NSW, Australia
| | - Ryan Childs
- Department of Pharmacology, School of Medicine, Western Sydney University, Penrith, NSW, Australia
| | - Garry Niedermayer
- School of Science, Western Sydney University, Penrith, NSW, Australia
| | - Rose Chesworth
- School of Medicine, Western Sydney University, Penrith, NSW, Australia
| | - Erika Gyengesi
- Department of Pharmacology, School of Medicine, Western Sydney University, Penrith, NSW, Australia
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23
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P2X7 Receptors Amplify CNS Damage in Neurodegenerative Diseases. Int J Mol Sci 2020; 21:ijms21175996. [PMID: 32825423 PMCID: PMC7504621 DOI: 10.3390/ijms21175996] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/07/2020] [Accepted: 08/17/2020] [Indexed: 12/11/2022] Open
Abstract
ATP is a (co)transmitter and signaling molecule in the CNS. It acts at a multitude of ligand-gated cationic channels termed P2X to induce rapid depolarization of the cell membrane. Within this receptor-channel family, the P2X7 receptor (R) allows the transmembrane fluxes of Na+, Ca2+, and K+, but also allows the slow permeation of larger organic molecules. This is supposed to cause necrosis by excessive Ca2+ influx, as well as depletion of intracellular ions and metabolites. Cell death may also occur by apoptosis due to the activation of the caspase enzymatic cascade. Because P2X7Rs are localized in the CNS preferentially on microglia, but also at a lower density on neuroglia (astrocytes, oligodendrocytes) the stimulation of this receptor leads to the release of neurodegeneration-inducing bioactive molecules such as pro-inflammatory cytokines, chemokines, proteases, reactive oxygen and nitrogen molecules, and the excitotoxic glutamate/ATP. Various neurodegenerative reactions of the brain/spinal cord following acute harmful events (mechanical CNS damage, ischemia, status epilepticus) or chronic neurodegenerative diseases (neuropathic pain, Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, amyotrophic lateral sclerosis) lead to a massive release of ATP via the leaky plasma membrane of neural tissue. This causes cellular damage superimposed on the original consequences of neurodegeneration. Hence, blood-brain-barrier permeable pharmacological antagonists of P2X7Rs with excellent bioavailability are possible therapeutic agents for these diseases. The aim of this review article is to summarize our present state of knowledge on the involvement of P2X7R-mediated events in neurodegenerative illnesses endangering especially the life quality and duration of the aged human population.
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Simpson DSA, Oliver PL. ROS Generation in Microglia: Understanding Oxidative Stress and Inflammation in Neurodegenerative Disease. Antioxidants (Basel) 2020; 9:E743. [PMID: 32823544 PMCID: PMC7463655 DOI: 10.3390/antiox9080743] [Citation(s) in RCA: 371] [Impact Index Per Article: 92.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/06/2020] [Accepted: 08/08/2020] [Indexed: 12/14/2022] Open
Abstract
Neurodegenerative disorders, such as Alzheimer's disease, are a global public health burden with poorly understood aetiology. Neuroinflammation and oxidative stress (OS) are undoubtedly hallmarks of neurodegeneration, contributing to disease progression. Protein aggregation and neuronal damage result in the activation of disease-associated microglia (DAM) via damage-associated molecular patterns (DAMPs). DAM facilitate persistent inflammation and reactive oxygen species (ROS) generation. However, the molecular mechanisms linking DAM activation and OS have not been well-defined; thus targeting these cells for clinical benefit has not been possible. In microglia, ROS are generated primarily by NADPH oxidase 2 (NOX2) and activation of NOX2 in DAM is associated with DAMP signalling, inflammation and amyloid plaque deposition, especially in the cerebrovasculature. Additionally, ROS originating from both NOX and the mitochondria may act as second messengers to propagate immune activation; thus intracellular ROS signalling may underlie excessive inflammation and OS. Targeting key kinases in the inflammatory response could cease inflammation and promote tissue repair. Expression of antioxidant proteins in microglia, such as NADPH dehydrogenase 1 (NQO1), is promoted by transcription factor Nrf2, which functions to control inflammation and limit OS. Lipid droplet accumulating microglia (LDAM) may also represent a double-edged sword in neurodegenerative disease by sequestering peroxidised lipids in non-pathological ageing but becoming dysregulated and pro-inflammatory in disease. We suggest that future studies should focus on targeted manipulation of NOX in the microglia to understand the molecular mechanisms driving inflammatory-related NOX activation. Finally, we discuss recent evidence that therapeutic target identification should be unbiased and founded on relevant pathophysiological assays to facilitate the discovery of translatable antioxidant and anti-inflammatory therapeutics.
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Affiliation(s)
- Dominic S. A. Simpson
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell, Oxfordshire OX11 0RD, UK;
- Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, UK
| | - Peter L. Oliver
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell, Oxfordshire OX11 0RD, UK;
- Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, UK
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25
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The Role of Neurovascular System in Neurodegenerative Diseases. Mol Neurobiol 2020; 57:4373-4393. [PMID: 32725516 DOI: 10.1007/s12035-020-02023-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 07/14/2020] [Indexed: 12/21/2022]
Abstract
The neurovascular system (NVS), which consisted of neurons, glia, and vascular cells, is a functional and structural unit of the brain. The NVS regulates blood-brain barrier (BBB) permeability and cerebral blood flow (CBF), thereby maintaining the brain's microenvironment for normal functioning, neuronal survival, and information processing. Recent studies have highlighted the role of vascular dysfunction in several neurodegenerative diseases. This is not unexpected since both nervous and vascular systems are functionally interdependent and show close anatomical apposition, as well as similar molecular pathways. However, despite extensive research, the precise mechanism by which neurovascular dysfunction contributes to neurodegeneration remains incomplete. Therefore, understanding the mechanisms of neurovascular dysfunction in disease conditions may allow us to develop potent and effective therapies for prevention and treatment of neurodegenerative diseases. This review article summarizes the current research in the context of neurovascular signaling associated with neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD). We also discuss the potential implication of neurovascular factor as a novel therapeutic target and prognostic marker in patients with neurodegenerative conditions. Graphical Abstract.
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26
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Cap KC, Jung YJ, Choi BY, Hyeon SJ, Kim JG, Min JK, Islam R, Hossain AJ, Chung WS, Suh SW, Ryu H, Park JB. Distinct dual roles of p-Tyr42 RhoA GTPase in tau phosphorylation and ATP citrate lyase activation upon different Aβ concentrations. Redox Biol 2020; 32:101446. [PMID: 32046944 PMCID: PMC7264465 DOI: 10.1016/j.redox.2020.101446] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/16/2020] [Accepted: 01/27/2020] [Indexed: 12/04/2022] Open
Abstract
Both the accumulation of Amyloid-β (Aβ) in plaques and phosphorylation of Tau protein (p-Tau) in neurofibrillary tangles have been identified as two major symptomatic features of Alzheimer's disease (AD). Despite of critical role of Aβ and p-Tau in AD progress, the interconnection of signalling pathways that Aβ induces p-Tau remains elusive. Herein, we observed that a popular AD model mouse (APP/PS1) and Aβ-injected mouse showed an increase in p-Tyr42 Rho in hippocampus of brain. Low concentrations of Aβ (1 μM) induced RhoA-mediated Ser422 phosphorylation of Tau protein (p-Ser422 Tau), but reduced the expression of ATP citrate lyase (ACL) in the HT22 hippocampal neuronal cell line. In contrast, high concentrations of Aβ (10 μM) along with high levels of superoxide production remarkably attenuated accumulation of p-Ser422 Tau, but augmented ACL expression and activated sterol regulatory element-binding protein 1 (SREBP1), leading to cellular senescence. Notably, a high concentration of Aβ (10 μM) induced nuclear localization of p-Tyr42 Rho, which positively regulated NAD kinase (NADK) expression by binding to the NADK promoter. Furthermore, severe AD patient brain showed high p-Tyr42 Rho levels. Collectively, our findings indicate that both high and low concentrations of Aβ are detrimental to neurons via distinct two p-Tyr42 RhoA-mediated signalling pathways in Ser422 phosphorylation of Tau and ACL expression.
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Affiliation(s)
- Kim Cuong Cap
- Department of Biochemistry, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea; Institute of Research and Development, Duy Tan University, Danang, 550000, Viet Nam
| | - Yeon-Joo Jung
- Department of Biological Science, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Bo Young Choi
- Department of Physiology, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea
| | - Seung Jae Hyeon
- Laboratory for Brain Gene Regulation and Epigenetics, Center for Neuromedicine, Brain Science Institute, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea
| | - Jae-Gyu Kim
- Department of Biochemistry, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea; Institute of Cell Differentiation and Aging, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea
| | - Jung-Ki Min
- Department of Biochemistry, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea
| | - Rokibul Islam
- Department of Biochemistry, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea; Department of Biotechnology and Genetic Engineering, Faculty of Biological Science, Islamic University, Kushtia, 7003, Bangladesh
| | - Abu Jubayer Hossain
- Department of Biochemistry, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea
| | - Won-Suk Chung
- Department of Biological Science, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Sang Won Suh
- Department of Physiology, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea
| | - Hoon Ryu
- Laboratory for Brain Gene Regulation and Epigenetics, Center for Neuromedicine, Brain Science Institute, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea
| | - Jae-Bong Park
- Department of Biochemistry, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea; Institute of Cell Differentiation and Aging, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea; Hallym Clinical and Translational Science Institute, Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea; eLmed Co., Hallym University College of Medicine, Chuncheon, Kangwon-do, 24252, Republic of Korea.
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27
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Shin JW, Lee JC. Roles of microglial membranes in Alzheimer's disease. CURRENT TOPICS IN MEMBRANES 2020; 86:301-314. [PMID: 33837697 PMCID: PMC8082413 DOI: 10.1016/bs.ctm.2020.08.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The majority of Alzheimer's disease (AD) risk genes are highly and selectively expressed by microglia in the brain. Several of these genes are related to lipid and cholesterol metabolism, lipid synthesis, lipid transport, endocytosis, exocytosis and phagocytosis. Therefore, studying the roles of cellular membrane biophysics in microglial function should improve our understanding of the AD pathology. In this chapter, we discuss how lipid rafts and membrane-cytoskeleton adhesion impact microglial-mediated oxidative stress and clearance of amyloid-β peptide (Aβ). We also discuss potential roles of lipid membrane-bound extracellular vesicles as carriers of pathological factors to promote inflammation and cytotoxicity.
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Affiliation(s)
- Jae-Won Shin
- Department of Bioengineering, University of Illinois at Chicago, College of Medicine, Chicago, IL, United States; Department of Pharmacology, University of Illinois at Chicago, College of Medicine, Chicago, IL, United States
| | - James C Lee
- Department of Bioengineering, University of Illinois at Chicago, College of Medicine, Chicago, IL, United States.
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Ravi SK, Narasingappa RB, Prasad M, Javagal MR, Vincent B. Cassia tora prevents Aβ 1-42 aggregation, inhibits acetylcholinesterase activity and protects against Aβ 1-42-induced cell death and oxidative stress in human neuroblastoma cells. Pharmacol Rep 2019; 71:1151-1159. [PMID: 31655280 DOI: 10.1016/j.pharep.2019.06.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 06/15/2019] [Accepted: 06/28/2019] [Indexed: 12/22/2022]
Abstract
BACKGROUND Alzheimer's is a complex neurodegenerative disease and is characterized by extraneuronal accumulation of β-amyloid peptide. Because of its complex nature, multi-target directed ligands (MTDLs) are increasingly being considered as promising anti-Alzheimer therapeutic agents. This study is aimed at determining the effects of Cassia tora ethyl acetate fraction on several Alzheimer-associated deleterious events in test tubes as well as in human neuroblastoma SK-N-SH and SH-SY5Y cell lines. METHOD Ethyl acetate fraction of C. tora was purified by chromatography, characterized by 1H and 13C NMR, and tested for its ability to prevent Aβ 1-42 aggregation by thioflavin-T fluorescence and transmission electron microscopy. We also analyzed the intracellular ROS level and cytotoxicity in SK-N-SH and SH-SY5Y cell lines. RESULTS The extract inhibits the formation of Aβ 1-42 aggregation from monomers and oligomers, as also acetylcholinesterase activity, Aβ 1-42 -induced cell death, and Aβ 1-42 -dependent intracellular ROS production in both SK-N-SH and SH-SY5Y cells. In-depth chromatographic and spectroscopic analysis of the extract revealed that the active molecules are most likely triglycerides of oleic acid (C18H34O2). CONCLUSION We demonstrate for the first time that Cassia tora fraction prevents Aβ 1-42 aggregation, inhibits acetylcholinesterase and alleviates Aβ 1-42 -induced oxidative stress in human neuroblastoma cells. We further suggest the possible use of triglycerides of oleic acid as efficient anti-Alzheimer agents.
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Affiliation(s)
- Sunil K Ravi
- Department of Biotechnology, A constituent College of University of Agriculture Sciences, Bangalore, Karnataka, India
| | - Ramesh B Narasingappa
- Department of Biotechnology, A constituent College of University of Agriculture Sciences, Bangalore, Karnataka, India.
| | - Mahadesh Prasad
- Department of Biochemstry, Pooja Bhagavat Memorial Mahajana Post Graduate Centre, Metagalli, Mysuru, Karnataka, India
| | - Manjunath R Javagal
- Department of Plantation Products, Spices and Flavour Technology, Central Food Technological Research Institute, Mysore, India
| | - Bruno Vincent
- Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, Thailand; Centre National de la Recherche Scientifique, Paris, France
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29
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Li HQ, Ip SP, Yuan QJ, Zheng GQ, Tsim KKW, Dong TTX, Lin G, Han Y, Liu Y, Xian YF, Lin ZX. Isorhynchophylline ameliorates cognitive impairment via modulating amyloid pathology, tau hyperphosphorylation and neuroinflammation: Studies in a transgenic mouse model of Alzheimer's disease. Brain Behav Immun 2019; 82:264-278. [PMID: 31476414 DOI: 10.1016/j.bbi.2019.08.194] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 08/14/2019] [Accepted: 08/27/2019] [Indexed: 12/22/2022] Open
Abstract
Isorhynchophylline (IRN) has been demonstrated to have distinct anti-Alzheimer's disease (AD) activity in several animal models of AD. In this study, we aimed at evaluating the preventive effect of IRN on the cognitive deficits and amyloid pathology in TgCRND8 mice. Male TgCRND8 mice were administered with IRN (20 or 40 mg/kg) by oral gavage daily for 4 months, followed by assessing the spatial learning and memory functions with the Radial Arm Maze (RAM) test. Brain tissues were determined immunohistochemically or biochemically for changes in amyloid pathology, tau hyperphosphorylation and neuroinflammation. Our results revealed that IRN (40 mg/kg) significantly ameliorated cognitive deficits in TgCRND8 mice. In addition, IRN (40 mg/kg) markedly reduced the levels of Aβ40, Aβ42 and tumor necrosis factor (TNF-α), interleukin 6 (IL-6) and IL-1β, and modulated the amyloid precursor protein (APP) processing and phosphorylation by altering the protein expressions of β-site APP cleaving enzyme-1 (BACE-1), phosphorylated APP (Thr668), presenilin-1 (PS-1) and anterior pharynx-defective-1 (APH-1), as well as insulin degrading enzyme (IDE), a major Aβ-degrading enzyme. IRN was also found to inhibit the phosphorylation of tau at the sites of Thr205 and Ser396. Immunofluorescence showed that IRN reduced the Aβ deposition, and suppressed the activation of microglia (Iba-1) and astrocytes (GFAP) in the cerebral cortex and hippocampus of TgCRND8 mice. Furthermore, IRN was able to attenuate the ratios of p-c-Jun/c-Jun and p-JNK/JNK in the brains of TgCRND8 mice. IRN also showed marked inhibitory effect on JNK signaling pathway in the Aβ-treated rat primary hippocampus neurons. We conclude that IRN improves cognitive impairment in TgCRND8 transgenic mice via reducing Aβ generation and deposition, tau hyperphosphorylation and neuroinflammation through inhibiting the activation of JNK signaling pathway, and has good potential for further development into pharmacological treatment for AD.
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Affiliation(s)
- Hui-Qin Li
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region.
| | - Siu-Po Ip
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region; Brain Research Centre, School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region.
| | - Qiu-Ju Yuan
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region; Brain Research Centre, School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region.
| | - Guo-Qing Zheng
- Department of Neurology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Zhejiang Province, PR China.
| | - Karl K W Tsim
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong Special Administrative Region.
| | - Tina T X Dong
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong Special Administrative Region.
| | - Ge Lin
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region.
| | - Yifan Han
- Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hong Kong Special Administrative Region.
| | - Yue Liu
- Cardiovascular Disease Centre, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, PR China.
| | - Yan-Fang Xian
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region; Brain Research Centre, School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region.
| | - Zhi-Xiu Lin
- School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region; Brain Research Centre, School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region; Hong Kong Institute of Integrative Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region.
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30
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Ballance WC, Qin EC, Chung HJ, Gillette MU, Kong H. Reactive oxygen species-responsive drug delivery systems for the treatment of neurodegenerative diseases. Biomaterials 2019; 217:119292. [PMID: 31279098 PMCID: PMC7081518 DOI: 10.1016/j.biomaterials.2019.119292] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 06/17/2019] [Accepted: 06/18/2019] [Indexed: 12/18/2022]
Abstract
Neurodegenerative diseases and disorders seriously impact memory and cognition and can become life-threatening. Current medical techniques attempt to combat these detrimental effects mainly through the administration of neuromedicine. However, drug efficacy is limited by rapid dispersal of the drugs to off-target sites while the site of administration is prone to overdose. Many neuropathological conditions are accompanied by excessive reactive oxygen species (ROS) due to the inflammatory response. Accordingly, ROS-responsive drug delivery systems have emerged as a promising solution. To guide intelligent and comprehensive design of ROS-responsive drug delivery systems, this review article discusses the two following topics: (1) the biology of ROS in both healthy and diseased nervous systems and (2) recent developments in ROS-responsive, drug delivery system design. Overall, this review article would assist efforts to make better decisions about designing ROS-responsive, neural drug delivery systems, including the selection of ROS-responsive functional groups.
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Affiliation(s)
- William C Ballance
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ellen C Qin
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Hee Jung Chung
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Martha U Gillette
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Cell & Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Hyunjoon Kong
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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31
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Lue LF, Beach TG, Walker DG. Alzheimer's Disease Research Using Human Microglia. Cells 2019; 8:cells8080838. [PMID: 31387311 PMCID: PMC6721636 DOI: 10.3390/cells8080838] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/31/2019] [Accepted: 07/31/2019] [Indexed: 02/06/2023] Open
Abstract
Experimental studies of neuroinflammation in Alzheimer's disease (AD) have mostly investigated microglia, the brain-resident macrophages. This review focused on human microglia obtained at rapid autopsies. Studies employing methods to isolate and culture human brain microglia in high purity for experimental studies were discussed. These methods were employed to isolate human microglia for investigation of a number of features of neuroinflammation, including activation phenotypes, neurotoxicity, responses to abnormal aggregated proteins such as amyloid beta, phagocytosis, and the effects of aging and disease on microglia cellular properties. In recent years, interest in human microglia and neuroinflammation has been renewed due to the identification of inflammation-related AD genetic risk factors, in particular the triggering receptor expressed on myeloid cells (TREM)-2. Because of the difficulties in developing effective treatments for AD, there has been a general need for greater understanding of the functions of microglia in normal and AD brains. While most experimental studies on neuroinflammation have employed rodent microglia, this review considered the role of human microglia in experimental studies. This review focused on the development of in vitro methodology for the culture of postmortem human microglia and the key findings obtained from experimental studies with these cells.
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Affiliation(s)
- Lih-Fen Lue
- Banner Sun Health Research Institute, Sun City, AZ, 85351, USA.
- Neurodegenerative Disease Research Center and School of Life Sciences, Arizona State University, Tempe, AZ 84027, USA.
| | - Thomas G Beach
- Banner Sun Health Research Institute, Sun City, AZ, 85351, USA
| | - Douglas G Walker
- Neurodegenerative Disease Research Center and School of Life Sciences, Arizona State University, Tempe, AZ 84027, USA
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Otsu 520, Japan
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32
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Barua S, Kim JY, Yenari MA, Lee JE. The role of NOX inhibitors in neurodegenerative diseases. IBRO Rep 2019; 7:59-69. [PMID: 31463415 PMCID: PMC6709343 DOI: 10.1016/j.ibror.2019.07.1721] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 07/27/2019] [Indexed: 02/06/2023] Open
Abstract
Oxidative stress is a key player in both chronic and acute brain disease due to the higher metabolic demand of the brain. Among the producers of free radicals, NADPH-oxidase (NOX) is a major contributor to oxidative stress in neurological disorders. In the brain, the superoxide produced by NOX is mainly found in leukocytes. However, recent studies have reported that it can be found in several other cell types. NOX has been reported to regulate neuronal signaling, memory processing, and central cardiovascular homeostasis. However, overproduction of NOX can contribute to neurotoxicity, CNS degeneration, and cardiovascular disorders. Regarding the above functions, NOX has been shown to play a crucial role in chronic CNS diseases like Parkinson's disease (PD), Alzheimer's disease (AD), Huntington's disease (HD), multiple sclerosis (MS), and amyotrophic lateral sclerosis (ALS), and in acute CNS disorders such as stroke, spinal cord injury, traumatic brain injury (TBI), and related cerebrovascular diseases. NOX is a multi-subunit complex consisting of two membrane-associated and four cytosolic subunits. Thus, in recent years, inhibition of NOX activity has drawn a great deal of attention from researchers in the field of treating chronic and acute CNS disorders and preventing secondary complications. Mounting evidence has shown that NOX inhibition is neuroprotective and that inhibiting NOX in circulating immune cells can improve neurological disease conditions. This review summarizes recent studies on the therapeutic effects and pharmacological strategies regarding NOX inhibitors in chronic and acute brain diseases and focuses on the hurdles that should be overcome before their clinical implementation.
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Affiliation(s)
- Sumit Barua
- Department of Anatomy, College of Medicine, Yonsei University, Republic of Korea
| | - Jong Youl Kim
- Department of Anatomy, College of Medicine, Yonsei University, Republic of Korea
| | - Midori A Yenari
- Department of Neurology, San Francisco Veterans Affairs Medical Center, University of California, San Francisco, 4150 Clement Street, MS 127, San Francisco, CA, 94121, United States
| | - Jong Eun Lee
- Department of Anatomy, College of Medicine, Yonsei University, Republic of Korea.,Brain Korea 21, PLUS Project for Medical Science, College of Medicine, Yonsei University, Republic of Korea.,Brain Research Institute, College of Medicine, Yonsei University, Republic of Korea
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33
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Angelopoulou E, Piperi C. Beneficial Effects of Fingolimod in Alzheimer's Disease: Molecular Mechanisms and Therapeutic Potential. Neuromolecular Med 2019; 21:227-238. [PMID: 31313064 DOI: 10.1007/s12017-019-08558-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 07/12/2019] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease (AD), the most common cause of dementia remains of unclear etiology with current pharmacological therapies failing to halt disease progression. Several pathophysiological mechanisms have been implicated in AD pathogenesis including amyloid-β protein (Aβ) accumulation, tau hyperphosphorylation, neuroinflammation and alterations in bioactive lipid metabolism. Sphingolipids, such as sphingosine-1-phosphate (S1P) and intracellular ceramide/S1P balance are highly implicated in central nervous system physiology as well as in AD pathogenesis. FTY720/Fingolimod, a structural sphingosine analog and S1P receptor (S1PR) modulator that is currently used in the treatment of relapsing-remitting multiple sclerosis (RRMS) has been shown to exert beneficial effects on AD progression. Recent in vitro and in vivo evidence indicate that fingolimod may suppress Aβ secretion and deposition, inhibit apoptosis and enhance brain-derived neurotrophic factor (BDNF) production. Furthermore, it regulates neuroinflammation, protects against N-methyl-D-aspartate (NMDA)-excitotoxicity and modulates receptor for advanced glycation end products signaling axis that is highly implicated in AD pathogenesis. This review discusses the underlying molecular mechanisms of the emerging neuroprotective role of fingolimod in AD and its therapeutic potential, aiming to shed more light on AD pathogenesis as well as direct future treatment strategies.
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Affiliation(s)
- Efthalia Angelopoulou
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75 M. Asias Street - Bldg 16, 11527, Athens, Greece
| | - Christina Piperi
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 75 M. Asias Street - Bldg 16, 11527, Athens, Greece.
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34
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Escitalopram Ameliorates Cognitive Impairment in D-Galactose-Injected Ovariectomized Rats: Modulation of JNK, GSK-3β, and ERK Signalling Pathways. Sci Rep 2019; 9:10056. [PMID: 31296935 PMCID: PMC6624366 DOI: 10.1038/s41598-019-46558-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 06/27/2019] [Indexed: 12/29/2022] Open
Abstract
Though selective serotonin reuptake inhibitors (SSRIs) have been found to increase cognitive performance in some studies on patients and animal models of Alzheimer's disease (AD), other studies have reported contradictory results, and the mechanism of action has not been fully described. This study aimed to examine the effect of escitalopram, an SSRI, in an experimental model of AD and to determine the involved intracellular signalling pathways. Ovariectomized rats were administered D-galactose (150 mg/kg/day, i.p) over ten weeks to induce AD. Treatment with escitalopram (10 mg/kg/day, p.o) for four weeks, starting from the 7th week of D-galactose injection, enhanced memory performance and attenuated associated histopathological changes. Escitalopram reduced hippocampal amyloid β 42, β-secretase, and p-tau, while increasing α-secretase levels. Furthermore, it decreased tumor necrosis factor-α, nuclear factor-kappa B p65, and NADPH oxidase, while enhancing brain-derived neurotrophic factor, phospho-cAMP response element binding protein, and synaptophysin levels. Moreover, escitalopram diminished the protein expression of the phosphorylated forms of c-Jun N-terminal kinase (JNK)/c-Jun, while increasing those of phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), glycogen synthase kinase-3β (GSK-3β), extracellular signal-regulated kinase (ERK) and its upstream kinases MEK and Raf-1. In conclusion, escitalopram ameliorated D-galactose/ovariectomy-induced AD-like features through modulation of PI3K/Akt/GSK-3β, Raf-1/MEK/ERK, and JNK/c-Jun pathways.
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35
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Nortley R, Korte N, Izquierdo P, Hirunpattarasilp C, Mishra A, Jaunmuktane Z, Kyrargyri V, Pfeiffer T, Khennouf L, Madry C, Gong H, Richard-Loendt A, Huang W, Saito T, Saido TC, Brandner S, Sethi H, Attwell D. Amyloid β oligomers constrict human capillaries in Alzheimer's disease via signaling to pericytes. Science 2019; 365:science.aav9518. [PMID: 31221773 DOI: 10.1126/science.aav9518] [Citation(s) in RCA: 366] [Impact Index Per Article: 73.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 04/10/2019] [Accepted: 06/04/2019] [Indexed: 12/17/2022]
Abstract
Cerebral blood flow is reduced early in the onset of Alzheimer's disease (AD). Because most of the vascular resistance within the brain is in capillaries, this could reflect dysfunction of contractile pericytes on capillary walls. We used live and rapidly fixed biopsied human tissue to establish disease relevance, and rodent experiments to define mechanism. We found that in humans with cognitive decline, amyloid β (Aβ) constricts brain capillaries at pericyte locations. This was caused by Aβ generating reactive oxygen species, which evoked the release of endothelin-1 (ET) that activated pericyte ETA receptors. Capillary, but not arteriole, constriction also occurred in vivo in a mouse model of AD. Thus, inhibiting the capillary constriction caused by Aβ could potentially reduce energy lack and neurodegeneration in AD.
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Affiliation(s)
- Ross Nortley
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Nils Korte
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Pablo Izquierdo
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Chanawee Hirunpattarasilp
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Anusha Mishra
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Zane Jaunmuktane
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK.,Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Vasiliki Kyrargyri
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Thomas Pfeiffer
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Lila Khennouf
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Christian Madry
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Hui Gong
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK
| | - Angela Richard-Loendt
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Wenhui Huang
- Molecular Physiology, CIPMM, University of Saarland, D-66421 Homburg, Germany
| | - Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Centre for Brain Science, Wako, Saitama 351-0198, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Centre for Brain Science, Wako, Saitama 351-0198, Japan
| | - Sebastian Brandner
- Division of Neuropathology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK.,Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Huma Sethi
- Division of Neurosurgery, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - David Attwell
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, UK.
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36
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Desler C, Lillenes MS, Tønjum T, Rasmussen LJ. The Role of Mitochondrial Dysfunction in the Progression of Alzheimer's Disease. Curr Med Chem 2019; 25:5578-5587. [PMID: 28618998 PMCID: PMC6446443 DOI: 10.2174/0929867324666170616110111] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Revised: 01/02/2017] [Accepted: 01/02/2017] [Indexed: 11/22/2022]
Abstract
The current molecular understanding of Alzheimer's disease (AD) has still not resulted in successful interventions. Mitochondrial dysfunction of the AD brain is currently emerging as a hallmark of this disease. One mitochondrial function often affected in AD is oxidative phosphorylation responsible for ATP production, but also for production of reactive oxygen species (ROS) and for the de novo synthesis of pyrimidines. This paper reviews the role of mitochondrial produced ROS and pyrimidines in the aetiology of AD and their proposed role in oxidative degeneration of macromolecules, synthesis of essential phospholipids and maintenance of mitochondrial viability in the AD brain.
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Affiliation(s)
- Claus Desler
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Denmark
| | - Meryl S Lillenes
- Healthy Brain Aging Centre (HBAC), Department of Microbiology, Oslo University Hospital, Oslo, Norway
| | - Tone Tønjum
- Healthy Brain Aging Centre (HBAC), Department of Microbiology, Oslo University Hospital, Oslo, Norway
| | - Lene Juel Rasmussen
- Center for Healthy Aging, Department of Cellular and Molecular Medicine, University of Copenhagen, Denmark
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Chen ST, Volle D, Jalil J, Wu P, Small GW. Health-Promoting Strategies for the Aging Brain. Am J Geriatr Psychiatry 2019; 27:213-236. [PMID: 30686664 DOI: 10.1016/j.jagp.2018.12.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/11/2018] [Accepted: 12/11/2018] [Indexed: 12/31/2022]
Abstract
As the world's population ages and people live longer, the changes in the aging brain present substantial challenges to our health and society. With greater longevity come age-related diseases, many of which have direct and indirect influences on the health of the brain. Although there is some degree of predictable decline in brain functioning with aging, meaningful cognitive decline is not inevitable and is perhaps preventable. In this review, we present the case that the course of aging-related brain disease and dysfunction can be modified. We present the evidence for conditions and risk factors that may contribute to cognitive decline and dementia and for interventions that may mitigate their impact on cognitive functioning later in life, or even prevent them and their cognitive sequelae from developing. Although much work remains to be done to meet the challenges of the aging brain, strategies to promote its health have been demonstrated and offer much promise, which can only be realized if we mount a vigorous public health effort to implement these strategies.
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Affiliation(s)
- Stephen T Chen
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles; the University of California, Los Angeles, Longevity Center, Los Angeles; David Geffen School of Medicine, University of California, Los Angeles, Los Angeles.
| | - Dax Volle
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles; the University of California, Los Angeles, Longevity Center, Los Angeles; David Geffen School of Medicine, University of California, Los Angeles, Los Angeles
| | - Jason Jalil
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles; the University of California, Los Angeles, Longevity Center, Los Angeles; David Geffen School of Medicine, University of California, Los Angeles, Los Angeles
| | - Pauline Wu
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles; the University of California, Los Angeles, Longevity Center, Los Angeles; David Geffen School of Medicine, University of California, Los Angeles, Los Angeles
| | - Gary W Small
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles; the University of California, Los Angeles, Longevity Center, Los Angeles; David Geffen School of Medicine, University of California, Los Angeles, Los Angeles
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Nordzieke DE, Medraño-Fernandez I. The Plasma Membrane: A Platform for Intra- and Intercellular Redox Signaling. Antioxidants (Basel) 2018; 7:antiox7110168. [PMID: 30463362 PMCID: PMC6262572 DOI: 10.3390/antiox7110168] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 11/15/2018] [Accepted: 11/17/2018] [Indexed: 02/06/2023] Open
Abstract
Membranes are of outmost importance to allow for specific signal transduction due to their ability to localize, amplify, and direct signals. However, due to the double-edged nature of reactive oxygen species (ROS)—toxic at high concentrations but essential signal molecules—subcellular localization of ROS-producing systems to the plasma membrane has been traditionally regarded as a protective strategy to defend cells from unwanted side-effects. Nevertheless, specialized regions, such as lipid rafts and caveolae, house and regulate the activated/inhibited states of important ROS-producing systems and concentrate redox targets, demonstrating that plasma membrane functions may go beyond acting as a securing lipid barrier. This is nicely evinced by nicotinamide adenine dinucleotide phosphate (NADPH)-oxidases (NOX), enzymes whose primary function is to generate ROS and which have been shown to reside in specific lipid compartments. In addition, membrane-inserted bidirectional H2O2-transporters modulate their conductance precisely during the passage of the molecules through the lipid bilayer, ensuring time-scaled delivery of the signal. This review aims to summarize current evidence supporting the role of the plasma membrane as an organizing center that serves as a platform for redox signal transmission, particularly NOX-driven, providing specificity at the same time that limits undesirable oxidative damage in case of malfunction. As an example of malfunction, we explore several pathological situations in which an inflammatory component is present, such as inflammatory bowel disease and neurodegenerative disorders, to illustrate how dysregulation of plasma-membrane-localized redox signaling impacts normal cell physiology.
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Affiliation(s)
- Daniela E Nordzieke
- Institute of Microbiology and Genetics, Department of Genetics of Eukaryotic Microorganisms, Georg August University Göttingen, Grisebachstr. 8, D-37077 Göttingen, Germany.
| | - Iria Medraño-Fernandez
- Protein Transport and Secretion Unit, Division of Genetics and Cell Biology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Ospedale San Raffaele, Università Vita-Salute San Raffaele, 20132 Milan, Italy.
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Bisht K, Sharma K, Tremblay MÈ. Chronic stress as a risk factor for Alzheimer's disease: Roles of microglia-mediated synaptic remodeling, inflammation, and oxidative stress. Neurobiol Stress 2018; 9:9-21. [PMID: 29992181 PMCID: PMC6035903 DOI: 10.1016/j.ynstr.2018.05.003] [Citation(s) in RCA: 206] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 02/23/2018] [Accepted: 05/14/2018] [Indexed: 02/07/2023] Open
Abstract
Microglia are the predominant immune cells of the central nervous system (CNS) that exert key physiological roles required for maintaining CNS homeostasis, notably in response to chronic stress, as well as mediating synaptic plasticity, learning and memory. The repeated exposure to stress confers a higher risk of developing neurodegenerative diseases including sporadic Alzheimer's disease (AD). While microglia have been causally linked to amyloid beta (Aβ) accumulation, tau pathology, neurodegeneration, and synaptic loss in AD, they were also attributed beneficial roles, notably in the phagocytic elimination of Aβ. In this review, we discuss the interactions between chronic stress and AD pathology, overview the roles played by microglia in AD, especially focusing on chronic stress as an environmental risk factor modulating their function, and present recently-described microglial phenotypes associated with neuroprotection in AD. These microglial phenotypes observed under both chronic stress and AD pathology may provide novel opportunities for the development of better-targeted therapeutic interventions.
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Key Words
- ABCA7, ATP-binding cassette transporter A7
- AD, Alzheimer's disease
- APOE, Apolipoprotein E
- APP, amyloid precursor protein
- Alzheimer's disease
- Aβ, Amyloid beta
- BDNF, brain derived neurotrophic factor
- CD11b, cluster of differentiation molecule 11B
- CD33, cluster of differentiation 33
- CNS, central nervous system
- CR, complement receptor
- CRF, corticotropin releasing factor
- DAM, disease associated microglia
- DAP12, DNAX-activation protein 12
- Dark microglia
- FAD, Familial Alzheimer's disease
- FCRLS, Fc receptor-like S scavenger receptor
- GR, glucocorticoid receptor
- HPA axis, hypothalamic pituitary adrenocortical axis
- IBA1, ionized calcium-binding adapter molecule 1
- IL, interleukin
- LTP, long-term potentiation
- MGnD, microglia with a neurodegenerative phenotype
- MR, mineralocorticoid receptor
- Microglia
- Microglial phenotypes
- NADPH, nicotinamide adenine dinucleotide phosphate
- NFT, neurofibrillary tangles
- Neurodegeneration
- Neuroinflammation
- PS, presenilin
- ROS, reactive oxygen species
- Stress
- Synaptic remodeling
- TGFβ, transforming growth factor β
- TLR, Toll-like receptors
- TMEM119, transmembrane protein 119
- TNFα, tumor necrosis factor-α
- TREM2, triggering receptor expressed in myeloid cells 2
- TYROBP, TYRO protein tyrosine kinase binding protein
- mPFC, medial prefrontal cortex
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Affiliation(s)
- Kanchan Bisht
- Axe Neurosciences, CRCHU de Québec-Université Laval, Québec, QC, Canada
| | - Kaushik Sharma
- Axe Neurosciences, CRCHU de Québec-Université Laval, Québec, QC, Canada
| | - Marie-Ève Tremblay
- Axe Neurosciences, CRCHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec, QC, Canada
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40
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Guedes JR, Lao T, Cardoso AL, El Khoury J. Roles of Microglial and Monocyte Chemokines and Their Receptors in Regulating Alzheimer's Disease-Associated Amyloid-β and Tau Pathologies. Front Neurol 2018; 9:549. [PMID: 30158892 PMCID: PMC6104478 DOI: 10.3389/fneur.2018.00549] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Accepted: 06/19/2018] [Indexed: 02/06/2023] Open
Abstract
Chemokines and their receptors have been shown to affect amyloid-β (Aβ) and tau pathologies in mouse models of Alzheimer's disease (AD) by regulating microglia and monocyte-associated neuroinflammation, microglial movement and monocyte recruitment into the brain. These cells in turn can promote and mediate Aβ phagocytosis and degradation and tau phosphorylation. In this review we discuss published work in this field in mouse models of AD and review what is known about the contributions of microglial and monocyte chemokines and their receptors to amyloid and tau pathologies. We focus on the roles of the chemokine/chemokine receptor pairs CCL2/CCR2, CX3CL1/CX3CR1, CCL5/CCR5, CXCL10/CXCR3 and CXCL1/CXCR2, highlighting important knowledge gaps in this field. A full understanding of the functions of chemokines and their receptors in AD may guide the development of novel immunotherapies for this devastating disease.
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Affiliation(s)
- Joana R Guedes
- Doctoral Programme in Experimental Biology and Biomedicine, CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal.,CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
| | - Taotao Lao
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
| | - Ana L Cardoso
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Joseph El Khoury
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States.,Division of Infectious Diseases, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
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Swanson A, Wolf T, Sitzmann A, Willette AA. Neuroinflammation in Alzheimer's disease: Pleiotropic roles for cytokines and neuronal pentraxins. Behav Brain Res 2018; 347:49-56. [PMID: 29462653 PMCID: PMC5988985 DOI: 10.1016/j.bbr.2018.02.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 01/30/2018] [Accepted: 02/13/2018] [Indexed: 12/14/2022]
Abstract
Neuroinflammation is a potential factor speculated to underlie Alzheimer's disease (AD) etiopathogenesis and progression. The overwhelming focus in this area of research to date has been on the chronic upregulation of pro-inflammatory cytokines to understand how neuroinflammatory mechanisms contribute to neurodegeneration. Yet, it is important to understand the pleiotropic roles of these cytokines in modulating neuroinflammation in which they cannot be labeled as a strictly "good" or "bad" biomarker phenotype. As such, biomarkers with more precise functions are needed to better understand how neuroinflammation impacts the brain in AD. Neuronal pentraxins are a concentration- dependent group of pro- or anti- inflammatory cytokines. There is contradictory evidence of these pentraxins as being both neuroprotective and potentially detrimental in AD. Potential neuroprotective examples include their ability to predict AD-related outcomes such as cognition, memory function and synaptic refinement. This review will briefly outline the basis of AD and subsequently summarize findings for neuropathological mechanisms of neuroinflammation, roles for traditional pro-and anti-inflammatory cytokines, and data found thus far on the neuronal pentraxins.
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Affiliation(s)
- Ashley Swanson
- Department of Food Science and Human Nutrition, Iowa State University, 2312 Food Sciences Building, 536 Farm House Lane, Ames, IA 50011, United States.
| | - Tovah Wolf
- Department of Food Science and Human Nutrition, Iowa State University, 2312 Food Sciences Building, 536 Farm House Lane, Ames, IA 50011, United States.
| | - Alli Sitzmann
- Department of Psychology, Iowa State University, W112 Lagomarcino Hall, 901 Stange Road, Ames, IA 50011, United States.
| | - Auriel A Willette
- Department of Food Science and Human Nutrition, Iowa State University, 2312 Food Sciences Building, 536 Farm House Lane, Ames, IA 50011, United States; Department of Psychology, Iowa State University, W112 Lagomarcino Hall, 901 Stange Road, Ames, IA 50011, United States; Department of Biomedical Sciences, Iowa State University, 2008 Veterinary Medicine, Ames, IA 50011, United States; Department of Neurology, University of Iowa, 2007 Roy Carver Pavilion, 200 Hawkins Drive, Iowa City, IA 52242, United States.
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42
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Watts ME, Pocock R, Claudianos C. Brain Energy and Oxygen Metabolism: Emerging Role in Normal Function and Disease. Front Mol Neurosci 2018; 11:216. [PMID: 29988368 PMCID: PMC6023993 DOI: 10.3389/fnmol.2018.00216] [Citation(s) in RCA: 187] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 06/01/2018] [Indexed: 01/09/2023] Open
Abstract
Dynamic metabolic changes occurring in neurons are critically important in directing brain plasticity and cognitive function. In other tissue types, disruptions to metabolism and the resultant changes in cellular oxidative state, such as increased reactive oxygen species (ROS) or induction of hypoxia, are associated with cellular stress. In the brain however, where drastic metabolic shifts occur to support physiological processes, subsequent changes to cellular oxidative state and induction of transcriptional sensors of oxidative stress likely play a significant role in regulating physiological neuronal function. Understanding the role of metabolism and metabolically-regulated genes in neuronal function will be critical in elucidating how cognitive functions are disrupted in pathological conditions where neuronal metabolism is affected. Here, we discuss known mechanisms regulating neuronal metabolism as well as the role of hypoxia and oxidative stress during normal and disrupted neuronal function. We also summarize recent studies implicating a role for metabolism in regulating neuronal plasticity as an emerging neuroscience paradigm.
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Affiliation(s)
- Michelle E Watts
- Queensland Brain Institute, The University of Queensland, St. Lucia, QLD, Australia
| | - Roger Pocock
- Development and Stem Cells Program, Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Charles Claudianos
- Queensland Brain Institute, The University of Queensland, St. Lucia, QLD, Australia.,Centre for Mental Health Research, The Australian National University, Canberra, ACT, Australia
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Gill I, Kaur S, Kaur N, Dhiman M, Mantha AK. Phytochemical Ginkgolide B Attenuates Amyloid-β1-42 Induced Oxidative Damage and Altered Cellular Responses in Human Neuroblastoma SH-SY5Y Cells. J Alzheimers Dis 2018; 60:S25-S40. [PMID: 28234255 DOI: 10.3233/jad-161086] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Oxidative stress is an upsurge in reactive oxygen/nitrogen species (ROS/RNS), which aggravates damage to cellular components viz. lipids, proteins, and nucleic acids resulting in impaired cellular functions and neurological pathologies including Alzheimer's disease (AD). In the present study, we have examined amyloid-β (Aβ)-induced oxidative stress responses, a major cause for AD, in the undifferentiated and differentiated human neuroblastoma SH-SY5Y cells. Aβ1-42-induced oxidative damage was evaluated on lipids by lipid peroxidation; proteins by protein carbonyls; antioxidant status by SOD and GSH enzyme activities; and DNA and RNA damage levels by evaluating the number of AP sites and 8-OHG base damages produced. In addition, the neuro-protective role of the phytochemical ginkgolide B (GB) in countering Aβ1-42-induced oxidative stress was assessed. We report that the differentiated cells are highly vulnerable to Aβ1-42-induced oxidative stress events as exerted by the deposition of Aβ in AD. Results of the current study suggest that the pre-treatment of GB, followed by Aβ1-42 treatment for 24 h, displayed neuro-protective potential, which countered Aβ1-42-induced oxidative stress responses in both undifferentiated and differentiated SH-SY5Y neuronal cells by: 1) hampering production of ROS and RNS; 2) reducing lipid peroxidation; 3) decreasing protein carbonyl content; 4) restoring antioxidant activities of SOD and GSH enzymes; and 5) maintaining genome integrity by reducing the oxidative DNA and RNA base damages. In conclusion, Aβ1-42 induces oxidative damage to the cellular biomolecules, which are associated with AD pathology, and are protected by the pre-treatment of GB against Aβ-toxicity. Taken together, this study advocates for phytochemical-based therapeutic interventions against AD.
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Affiliation(s)
- Iqbal Gill
- Centre for Animal Sciences, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, Punjab, India
| | - Sukhchain Kaur
- Centre for Biochemistry and Microbial Sciences, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, Punjab, India
| | - Navrattan Kaur
- Centre for Animal Sciences, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, Punjab, India
| | - Monisha Dhiman
- Centre for Biochemistry and Microbial Sciences, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, Punjab, India
| | - Anil K Mantha
- Centre for Animal Sciences, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, Punjab, India
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44
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Jin P, Pan Y, Pan Z, Xu J, Lin M, Sun Z, Chen M, Xu M. Alzheimer-like brain metabolic and structural features in cholesterol-fed rabbit detected by magnetic resonance imaging. Lipids Health Dis 2018; 17:61. [PMID: 29587752 PMCID: PMC5870103 DOI: 10.1186/s12944-018-0705-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Accepted: 03/09/2018] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Hypercholesterolemia is known to increase the risk of AD in later life, the purpose of this study is to illustrate brain metabolic and structural changes in a cholesterol-fed rabbit model of Alzheimer's Disease (AD) by using clinical 3 T Magnetic Resonance Imaging (MRI). METHODS The Institutional Animal Care and Use Committee of Zhejiang Chinese Medical University approved the study. Totally 16 Japanese White Rabbits (JWR) were randomly divided into 2 groups including normal control group fed with routine diet (group NC) and high cholesterol diet group (group CD) fed a 2% cholesterol diet with 0.24 ppm copper in the drinking water for 12 weeks. Magnetic resonance spectroscopy (MRS) and structural image of rabbit brain were performed by using a 3 Tesla (T) MRI scanner with an 8 channel Rabbit coil. The chemical metabolites were identified by LC Model including N-acetylaspartate (NAA), creatine (Cr), glutamate (Glu), glutamine (Gln), Glycerophosphatidylcholine (GPC), phosphorylcholine (PCH), and myoinositol (MI). The relative concentrations (/Cr) were analyzed. Additionally, Amyloid-β (Aβ) accumulation in the brain was measured postmortem. For comparisons of MR and Aβ data between groups, two-tailed t-tests were performed. RESULTS The ratio of NAA/Cr (0.76 ± 0.10) and Glu/Cr (0.90 ± 0.14) in group CD were lower than those in the group NC (0.87 ± 0.06, 1.13 ± 0.22, respectively, P < 0.05). Compared to the group NC (2.88 ± 0.09 cm3, 0.63 ± 0.08 cm3, respectively), the cortical and hippocampal volumes (2.60 ± 0.14 cm3 and 0.47 ± 0.07 cm3, respectively) of rabbits brain decreased in the group CD while the third and lateral ventricular volumes enlarged (44.56 ± 6.01 mm3 vs 31.40 ± 6.14 mm3, 261.40 ± 30.98 mm3 vs 153.81 ± 30.08 mm3, P < 0.05). These metabolic and structural changes were additionally accompanied by the significant increase of Aβ1-42 in the cortex and hippocampus (163.60 ± 16.26 pg/mg and 215.20 ± 69.86 pg/mg, respectively, P < 0.05). CONCLUSION High cholesterol diet can induce the brain metabolic and structural changes of the rabbit including lowered level of NAA and Glu and the atrophy of the brain which were similar to those of human AD.
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Affiliation(s)
- Ping Jin
- The First Affiliated Hospital of Zhejiang Chinese Medical University, No. 54 Youdian Road, Shangcheng District, Hangzhou, Zhejiang 310006 People’s Republic of China
- The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang China
| | - Yongming Pan
- Laboratory Animal Research Center/Comparative Medical Research Institute, Zhejiang Chinese Medical University, No 548 Binwen Road, Binjiang District, Hangzhou, 310053 China
| | - Zhiyong Pan
- The First Affiliated Hospital of Zhejiang Chinese Medical University, No. 54 Youdian Road, Shangcheng District, Hangzhou, Zhejiang 310006 People’s Republic of China
| | - Jianqin Xu
- Laboratory Animal Research Center/Comparative Medical Research Institute, Zhejiang Chinese Medical University, No 548 Binwen Road, Binjiang District, Hangzhou, 310053 China
| | - Min Lin
- The Third Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang China
| | - Zhichao Sun
- The First Affiliated Hospital of Zhejiang Chinese Medical University, No. 54 Youdian Road, Shangcheng District, Hangzhou, Zhejiang 310006 People’s Republic of China
| | - Minli Chen
- Laboratory Animal Research Center/Comparative Medical Research Institute, Zhejiang Chinese Medical University, No 548 Binwen Road, Binjiang District, Hangzhou, 310053 China
| | - Maosheng Xu
- The First Affiliated Hospital of Zhejiang Chinese Medical University, No. 54 Youdian Road, Shangcheng District, Hangzhou, Zhejiang 310006 People’s Republic of China
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Maione F, Piccolo M, De Vita S, Chini MG, Cristiano C, De Caro C, Lippiello P, Miniaci MC, Santamaria R, Irace C, De Feo V, Calignano A, Mascolo N, Bifulco G. Down regulation of pro-inflammatory pathways by tanshinone IIA and cryptotanshinone in a non-genetic mouse model of Alzheimer’s disease. Pharmacol Res 2018; 129:482-490. [DOI: 10.1016/j.phrs.2017.11.018] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 09/26/2017] [Accepted: 11/16/2017] [Indexed: 01/02/2023]
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46
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P-glycoprotein (ABCB1) and Oxidative Stress: Focus on Alzheimer's Disease. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:7905486. [PMID: 29317984 PMCID: PMC5727796 DOI: 10.1155/2017/7905486] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 10/30/2017] [Indexed: 11/23/2022]
Abstract
ATP-binding cassette (ABC) transporters, in particular P-glycoprotein (encoded by ABCB1), are important and selective elements of the blood-brain barrier (BBB), and they actively contribute to brain homeostasis. Changes in ABCB1 expression and/or function at the BBB may not only alter the expression and function of other molecules at the BBB but also affect brain environment. Over the last decade, a number of reports have shown that ABCB1 actively mediates the transport of beta amyloid (Aβ) peptide. This finding has opened up an entirely new line of research in the field of Alzheimer's disease (AD). Indeed, despite intense research efforts, AD remains an unsolved pathology and effective therapies are still unavailable. Here, we review the crucial role of ABCB1 in the Aβ transport and how oxidative stress may interfere with this process. A detailed understanding of ABCB1 regulation can provide the basis for improved neuroprotection in AD and also enhanced therapeutic drug delivery to the brain.
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47
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Chronic cerebral hypoperfusion alters amyloid-β peptide pools leading to cerebral amyloid angiopathy, microinfarcts and haemorrhages in Tg-SwDI mice. Clin Sci (Lond) 2017; 131:2109-2123. [PMID: 28667120 DOI: 10.1042/cs20170962] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 06/22/2017] [Accepted: 06/29/2017] [Indexed: 02/07/2023]
Abstract
Cerebral hypoperfusion is an early feature of Alzheimer's disease (AD) that influences the progression from mild cognitive impairment to dementia. Understanding the mechanism is of critical importance in the search for new effective therapies. We hypothesized that cerebral hypoperfusion promotes the accumulation of amyloid-β (Aβ) and degenerative changes in the brain and is a potential mechanism contributing to development of dementia. To address this, we studied the effects of chronic cerebral hypoperfusion induced by bilateral carotid artery stenosis on Aβ peptide pools in a transgenic mouse model of AD (transgenic mice with Swedish, Dutch and Iowa mutations in human amyloid precursor protein (APP) (Tg-SwDI)). Cerebrovascular integrity was characterized by quantifying the occurrence of microinfarcts and haemorrhages and compared with wild-type mice without Aβ. A significant increase in soluble Aβ peptides (Aβ40/42) was detected after 1 month of hypoperfusion in the parenchyma in parallel with elevated APP and APP proteolytic products. Following 3 months, a significant increase in insoluble Aβ40/42 was determined in the parenchyma and vasculature. Microinfarct load was significantly increased in the Tg-SwDI as compared with wild-type mice and further exacerbated by hypoperfusion at 1 and 3 months. In addition, the number of Tg-SwDI hypoperfused mice with haemorrhages was increased compared with hypoperfused wild-type mice. Soluble parenchymal Aβ was associated with elevated NADPH oxidase-2 (NOX2) which was exacerbated by 1-month hypoperfusion. We suggest that in response to hypoperfusion, increased Aβ production/deposition may contribute to degenerative processes by triggering oxidative stress promoting cerebrovascular disruption and the development of microinfarcts.
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48
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Pietronigro EC, Della Bianca V, Zenaro E, Constantin G. NETosis in Alzheimer's Disease. Front Immunol 2017; 8:211. [PMID: 28303140 PMCID: PMC5332471 DOI: 10.3389/fimmu.2017.00211] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 02/15/2017] [Indexed: 12/21/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by the progressive deterioration of cognitive functions. Its neuropathological features include amyloid-β (Aβ) accumulation, the formation of neurofibrillary tangles, and the loss of neurons and synapses. Neuroinflammation is a well-established feature of AD pathogenesis, and a better understanding of its mechanisms could facilitate the development of new therapeutic approaches. Recent studies in transgenic mouse models of AD have shown that neutrophils adhere to blood vessels and migrate inside the parenchyma. Moreover, studies in human AD subjects have also shown that neutrophils adhere and spread inside brain vessels and invade the parenchyma, suggesting these cells play a role in AD pathogenesis. Indeed, neutrophil depletion and the therapeutic inhibition of neutrophil trafficking, achieved by blocking LFA-1 integrin in AD mouse models, significantly reduced memory loss and the neuropathological features of AD. We observed that neutrophils release neutrophil extracellular traps (NETs) inside blood vessels and in the parenchyma of AD mice, potentially harming the blood–brain barrier and neural cells. Furthermore, confocal microscopy confirmed the presence of NETs inside the cortical vessels and parenchyma of subjects with AD, providing more evidence that neutrophils and NETs play a role in AD-related tissue destruction. The discovery of NETs inside the AD brain suggests that these formations may exacerbate neuro-inflammatory processes, promoting vascular and parenchymal damage during AD. The inhibition of NET formation has achieved therapeutic benefits in several models of chronic inflammatory diseases, including autoimmune diseases affecting the brain. Therefore, the targeting of NETs may delay AD pathogenesis and offer a novel approach for the treatment of this increasingly prevalent disease.
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Affiliation(s)
| | - Vittorina Della Bianca
- Department of Medicine, Section of General Pathology, University of Verona , Verona , Italy
| | - Elena Zenaro
- Department of Medicine, Section of General Pathology, University of Verona , Verona , Italy
| | - Gabriela Constantin
- Department of Medicine, Section of General Pathology, University of Verona , Verona , Italy
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49
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Ma MW, Wang J, Zhang Q, Wang R, Dhandapani KM, Vadlamudi RK, Brann DW. NADPH oxidase in brain injury and neurodegenerative disorders. Mol Neurodegener 2017; 12:7. [PMID: 28095923 PMCID: PMC5240251 DOI: 10.1186/s13024-017-0150-7] [Citation(s) in RCA: 284] [Impact Index Per Article: 40.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 01/05/2017] [Indexed: 12/11/2022] Open
Abstract
Oxidative stress is a common denominator in the pathology of neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, and multiple sclerosis, as well as in ischemic and traumatic brain injury. The brain is highly vulnerable to oxidative damage due to its high metabolic demand. However, therapies attempting to scavenge free radicals have shown little success. By shifting the focus to inhibit the generation of damaging free radicals, recent studies have identified NADPH oxidase as a major contributor to disease pathology. NADPH oxidase has the primary function to generate free radicals. In particular, there is growing evidence that the isoforms NOX1, NOX2, and NOX4 can be upregulated by a variety of neurodegenerative factors. The majority of recent studies have shown that genetic and pharmacological inhibition of NADPH oxidase enzymes are neuroprotective and able to reduce detrimental aspects of pathology following ischemic and traumatic brain injury, as well as in chronic neurodegenerative disorders. This review aims to summarize evidence supporting the role of NADPH oxidase in the pathology of these neurological disorders, explores pharmacological strategies of targeting this major oxidative stress pathway, and outlines obstacles that need to be overcome for successful translation of these therapies to the clinic.
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Affiliation(s)
- Merry W Ma
- Charlie Norwood VA Medical Center, One Freedom Way, Augusta, GA, 30904, USA.,Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, 1120 Fifteenth Street, Augusta, GA, 30912, USA
| | - Jing Wang
- Charlie Norwood VA Medical Center, One Freedom Way, Augusta, GA, 30904, USA.,Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, 1120 Fifteenth Street, Augusta, GA, 30912, USA
| | - Quanguang Zhang
- Charlie Norwood VA Medical Center, One Freedom Way, Augusta, GA, 30904, USA.,Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, 1120 Fifteenth Street, Augusta, GA, 30912, USA
| | - Ruimin Wang
- Charlie Norwood VA Medical Center, One Freedom Way, Augusta, GA, 30904, USA.,Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, 1120 Fifteenth Street, Augusta, GA, 30912, USA
| | - Krishnan M Dhandapani
- Charlie Norwood VA Medical Center, One Freedom Way, Augusta, GA, 30904, USA.,Department of Neurosurgery, Medical College of Georgia, Augusta University, 1120 Fifteenth Street, Augusta, GA, 30912, USA
| | - Ratna K Vadlamudi
- Department of Obstetrics and Gynecology, University of Texas Health Science Center, 7703 Medical Drive, San Antonio, TX, 78229, USA
| | - Darrell W Brann
- Charlie Norwood VA Medical Center, One Freedom Way, Augusta, GA, 30904, USA. .,Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, 1120 Fifteenth Street, Augusta, GA, 30912, USA.
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Rastogi R, Geng X, Li F, Ding Y. NOX Activation by Subunit Interaction and Underlying Mechanisms in Disease. Front Cell Neurosci 2017; 10:301. [PMID: 28119569 PMCID: PMC5222855 DOI: 10.3389/fncel.2016.00301] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Accepted: 12/20/2016] [Indexed: 12/19/2022] Open
Abstract
Nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase (NOX) is an enzyme complex with the sole function of producing superoxide anion and reactive oxygen species (ROS) at the expense of NADPH. Vital to the immune system as well as cellular signaling, NOX is also involved in the pathologies of a wide variety of disease states. Particularly, it is an integral player in many neurological diseases, including stroke, TBI, and neurodegenerative diseases. Pathologically, NOX produces an excessive amount of ROS that exceed the body’s antioxidant ability to neutralize them, leading to oxidative stress and aberrant signaling. This prevalence makes it an attractive therapeutic target and as such, NOX inhibitors have been studied and developed to counter NOX’s deleterious effects. However, recent studies of NOX have created a better understanding of the NOX complex. Comprised of independent cytosolic subunits, p47-phox, p67-phox, p40-phox and Rac, and membrane subunits, gp91-phox and p22-phox, the NOX complex requires a unique activation process through subunit interaction. Of these subunits, p47-phox plays the most important role in activation, binding and translocating the cytosolic subunits to the membrane and anchoring to p22-phox to organize the complex for NOX activation and function. Moreover, these interactions, particularly that between p47-phox and p22-phox, are dependent on phosphorylation initiated by upstream processes involving protein kinase C (PKC). This review will look at these interactions between subunits and with PKC. It will focus on the interaction involving p47-phox with p22-phox, key in bringing the cytosolic subunits to the membrane. Furthermore, the implication of these interactions as a target for NOX inhibitors such as apocynin will be discussed as a potential avenue for further investigation, in order to develop more specific NOX inhibitors based on the inhibition of NOX assembly and activation.
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Affiliation(s)
- Radhika Rastogi
- Department of Neurosurgery, Wayne State University School of Medicine Detroit, MI, USA
| | - Xiaokun Geng
- Department of Neurosurgery, Wayne State University School of MedicineDetroit, MI, USA; China-America Institute of Neuroscience, Beijing Luhe Hospital, Capital Medical UniversityBeijing, China; Department of Neurology, Beijing Luhe Hospital, Capital Medical UniversityBeijing, China
| | - Fengwu Li
- China-America Institute of Neuroscience, Beijing Luhe Hospital, Capital Medical University Beijing, China
| | - Yuchuan Ding
- Department of Neurosurgery, Wayne State University School of MedicineDetroit, MI, USA; China-America Institute of Neuroscience, Beijing Luhe Hospital, Capital Medical UniversityBeijing, China
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