151
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Green tea extract attenuates LPS-induced retinal inflammation in rats. Sci Rep 2018; 8:429. [PMID: 29323215 PMCID: PMC5765135 DOI: 10.1038/s41598-017-18888-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 12/19/2017] [Indexed: 01/05/2023] Open
Abstract
Inflammation is in a wide spectrum of retinal diseases, causing irreversible blindness and visual impairment. We have previously demonstrated that Green Tea Extract (GTE) is a potent anti-inflammatory agent for anterior uveitis. Here we investigated the anti-inflammatory effect of GTE on lipopolysaccharides (LPS)-induced retinal inflammation in rats and explored the underlying mechanism. Adult rats were injected with LPS and GTE was administered intra-gastrically at 2, 8, 26 and 32 hours post-injection. Staining of whole-mount retina showed that the number of activated microglia cells was significantly increased at 48 hours post-injection, which was suppressed after GTE treatment in a dose-dependent manner. Activation of astrocytes and Müller glia in the retina was also suppressed after GTE treatment. Meanwhile, GTE reduced the expression of pro-inflammatory cytokines including IL-1β, TNF-α and IL-6 in retina and vitreous humor. These anti-inflammatory effects were associated with a reduced phosphorylation of STAT3 and NF-κB in the retina. Furthermore, the surface receptor of EGCG, 67LR, was localized on the neurons and glia in the retina. These findings demonstrate that GTE is an effective agent in suppressing LPS-induced retinal inflammation, probably through its potent anti-oxidative property and a receptor-mediated action on transcription factors that regulate production of pro-inflammatory cytokines.
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152
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Freyssin A, Page G, Fauconneau B, Rioux Bilan A. Natural polyphenols effects on protein aggregates in Alzheimer's and Parkinson's prion-like diseases. Neural Regen Res 2018; 13:955-961. [PMID: 29926816 PMCID: PMC6022479 DOI: 10.4103/1673-5374.233432] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Alzheimer's and Parkinson's diseases are the most common neurodegenerative diseases. They are characterized by protein aggregates and so can be considered as prion-like disease. The major components of these deposits are amyloid peptide and tau for Alzheimer's disease, α-synuclein and synphilin-1 for Parkinson's disease. Drugs currently proposed to treat these pathologies do not prevent neurodegenerative processes and are mainly symptomatic therapies. Molecules inducing inhibition of aggregation or disaggregation of these proteins could have beneficial effects, especially if they have other beneficial effects for these diseases. Thus, several natural polyphenols, which have antioxidative, anti-inflammatory and neuroprotective properties, have been largely studied, for their effects on protein aggregates found in these diseases, notably in vitro. In this article, we propose to review the significant papers concerning the role of polyphenols on aggregation and disaggregation of amyloid peptide, tau, α-synuclein, synphilin-1, suggesting that these compounds could be useful in the treatments in Alzheimer's and Parkinson's diseases.
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Affiliation(s)
- Aline Freyssin
- University of Poitiers, EA3808 NEUVACOD (Neurovascular Unit and Cognitive Disorders), Pôle Biologie Santé, Poitiers, France
| | - Guylène Page
- University of Poitiers, EA3808 NEUVACOD (Neurovascular Unit and Cognitive Disorders), Pôle Biologie Santé, Poitiers, France
| | - Bernard Fauconneau
- University of Poitiers, EA3808 NEUVACOD (Neurovascular Unit and Cognitive Disorders), Pôle Biologie Santé, Poitiers, France
| | - Agnès Rioux Bilan
- University of Poitiers, EA3808 NEUVACOD (Neurovascular Unit and Cognitive Disorders), Pôle Biologie Santé, Poitiers, France
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153
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Ruzicka J, Urdzikova LM, Svobodova B, Amin AG, Karova K, Dubisova J, Zaviskova K, Kubinova S, Schmidt M, Jhanwar-Uniyal M, Jendelova P. Does combined therapy of curcumin and epigallocatechin gallate have a synergistic neuroprotective effect against spinal cord injury? Neural Regen Res 2018; 13:119-127. [PMID: 29451216 PMCID: PMC5840977 DOI: 10.4103/1673-5374.224379] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Systematic inflammatory response after spinal cord injury (SCI) is one of the factors leading to lesion development and a profound degree of functional loss. Anti-inflammatory compounds, such as curcumin and epigallocatechin gallate (EGCG) are known for their neuroprotective effects. In this study, we investigated the effect of combined therapy of curcumin and EGCG in a rat model of acute SCI induced by balloon compression. Immediately after SCI, rats received curcumin, EGCG, curcumin + EGCG or saline [daily intraperitoneal doses (curcumin, 6 mg/kg; EGCG 17 mg/kg)] and weekly intramuscular doses (curcumin, 60 mg/kg; EGCG 17 mg/kg)] for 28 days. Rats were evaluated using behavioral tests (the Basso, Beattie, and Bresnahan (BBB) open-field locomotor test, flat beam test). Spinal cord tissue was analyzed using histological methods (Luxol Blue-cresyl violet staining) and immunohistochemistry (anti-glial fibrillary acidic protein, anti-growth associated protein 43). Cytokine levels (interleukin-1β, interleukin-4, interleukin-2, interleukin-6, macrophage inflammatory protein 1-alpha, and RANTES) were measured using Luminex assay. Quantitative polymerase chain reaction was performed to determine the relative expression of genes (Sort1, Fgf2, Irf5, Mrc1, Olig2, Casp3, Gap43, Gfap, Vegf, NfκB, Cntf) related to regenerative processes in injured spinal cord. We found that all treatments displayed significant behavioral recovery, with no obvious synergistic effect after combined therapy of curcumin and ECGC. Curcumin and EGCG alone or in combination increased axonal sprouting, decreased glial scar formation, and altered the levels of macrophage inflammatory protein 1-alpha, interleukin-1β, interleukin-4 and interleukin-6 cytokines. These results imply that although the expected synergistic response of this combined therapy was less obvious, aspects of tissue regeneration and immune responses in severe SCI were evident.
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Affiliation(s)
- Jiri Ruzicka
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Vídenská, Prague, Czech Republic
| | - Lucia Machova Urdzikova
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Vídenská, Prague, Czech Republic
| | - Barbora Svobodova
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Vídeňská; Department of Neuroscience, Charles University, Second Faculty of Medicine, Prague, Czech Republic
| | | | - Kristyna Karova
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Vídeňská; Department of Neuroscience, Charles University, Second Faculty of Medicine, Prague, Czech Republic
| | - Jana Dubisova
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Vídeňská; Department of Neuroscience, Charles University, Second Faculty of Medicine, Prague, Czech Republic
| | - Kristyna Zaviskova
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Vídeňská; Department of Neuroscience, Charles University, Second Faculty of Medicine, Prague, Czech Republic
| | - Sarka Kubinova
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Vídenská, Prague, Czech Republic
| | | | | | - Pavla Jendelova
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Vídeňská; Department of Neuroscience, Charles University, Second Faculty of Medicine, Prague, Czech Republic
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154
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Doig AJ. Positive Feedback Loops in Alzheimer's Disease: The Alzheimer's Feedback Hypothesis. J Alzheimers Dis 2018; 66:25-36. [PMID: 30282364 PMCID: PMC6484277 DOI: 10.3233/jad-180583] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/08/2018] [Indexed: 12/17/2022]
Abstract
The dominant model for Alzheimer's disease (AD) is the amyloid cascade hypothesis, in which the accumulation of excess amyloid-β (Aβ) leads to inflammation, excess glutamate and intracellular calcium, oxidative stress, tau hyperphosphorylation and tangle formation, neuronal loss, and ultimately dementia. In a cascade, AD proceeds in a unidirectional fashion, with events only affecting downstream processes. Compelling evidence now exists for the presence of positive feedback loops in AD, however, involving oxidative stress, inflammation, glutamate, calcium, and tau. The pathological state of AD is thus a system of positive feedback loops, leading to amplification of the initial perturbation, rather than a linear cascade. Drugs may therefore be effective by targeting numerous points within the loops, rather than concentrating on upstream processes. Anti-inflammatories and anti-oxidants may be especially valuable, since these processes are involved in many loops and hence would affect numerous processes in AD.
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Affiliation(s)
- Andrew J. Doig
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology Medicine and Health, Oxford Road, University of Manchester, UK
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155
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Protein and Peptides for Elderly Health. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2018; 112:265-308. [DOI: 10.1016/bs.apcsb.2018.03.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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156
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Jia JJ, Zeng XS, Song XQ, Zhang PP, Chen L. Diabetes Mellitus and Alzheimer's Disease: The Protection of Epigallocatechin-3-gallate in Streptozotocin Injection-Induced Models. Front Pharmacol 2017; 8:834. [PMID: 29209211 PMCID: PMC5702501 DOI: 10.3389/fphar.2017.00834] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 11/01/2017] [Indexed: 12/27/2022] Open
Abstract
Diabetes mellitus is considered as a risk factor of Alzheimer’s disease (AD), the front runner of neurodegenerative disorders. Streptozotocin (STZ) is a toxin for pancreatic β-cell, which can construct a model of insulin deficient diabetes through intraperitoneal or intravenous injection. A model generated by intracerebroventricular STZ (icv-STZ) also shows numerous aspects of sporadic AD. The protective roles of tea polyphenols epigallocatechin-3-gallate (EGCG) on both two diseases were researched by some scientists. This review highlights the link between diabetes and AD and recent studies on STZ injection-induced models, and also discusses the protection of EGCG to clarify its treatment in STZ-induced diabetes and AD.
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Affiliation(s)
- Jin-Jing Jia
- College of Life Sciences, Xinyang Normal University, Xinyang, China.,Institute for Conservation and Utilization of Agro-bioresources in Dabie Mountains, Xinyang Normal University, Xinyang, China.,Henan Key Laboratory of Tea Biology, Xinyang Normal University, Xinyang, China
| | - Xian-Si Zeng
- College of Life Sciences, Xinyang Normal University, Xinyang, China.,Institute for Conservation and Utilization of Agro-bioresources in Dabie Mountains, Xinyang Normal University, Xinyang, China.,Henan Key Laboratory of Tea Biology, Xinyang Normal University, Xinyang, China
| | - Xin-Qiang Song
- College of Life Sciences, Xinyang Normal University, Xinyang, China
| | - Peng-Peng Zhang
- College of Life Sciences, Xinyang Normal University, Xinyang, China
| | - Lei Chen
- College of Life Sciences, Xinyang Normal University, Xinyang, China
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157
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Jan AT, Azam M, Rahman S, Almigeiti AMS, Choi DH, Lee EJ, Haq QMR, Choi I. Perspective Insights into Disease Progression, Diagnostics, and Therapeutic Approaches in Alzheimer's Disease: A Judicious Update. Front Aging Neurosci 2017; 9:356. [PMID: 29163138 PMCID: PMC5671974 DOI: 10.3389/fnagi.2017.00356] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 10/18/2017] [Indexed: 01/22/2023] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the progressive accumulation of β-amyloid fibrils and abnormal tau proteins in and outside of neurons. Representing a common form of dementia, aggravation of AD with age increases the morbidity rate among the elderly. Although, mutations in the ApoE4 act as potent risk factors for sporadic AD, familial AD arises through malfunctioning of APP, PSEN-1, and−2 genes. AD progresses through accumulation of amyloid plaques (Aβ) and neurofibrillary tangles (NFTs) in brain, which interfere with neuronal communication. Cellular stress that arises through mitochondrial dysfunction, endoplasmic reticulum malfunction, and autophagy contributes significantly to the pathogenesis of AD. With high accuracy in disease diagnostics, Aβ deposition and phosphorylated tau (p-tau) are useful core biomarkers in the cerebrospinal fluid (CSF) of AD patients. Although five drugs are approved for treatment in AD, their failures in achieving complete disease cure has shifted studies toward a series of molecules capable of acting against Aβ and p-tau. Failure of biologics or compounds to cross the blood-brain barrier (BBB) in most cases advocates development of an efficient drug delivery system. Though liposomes and polymeric nanoparticles are widely adopted for drug delivery modules, their use in delivering drugs across the BBB has been overtaken by exosomes, owing to their promising results in reducing disease progression.
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Affiliation(s)
- Arif Tasleem Jan
- Department of Medical Biotechnology, Yeungnam University, Gyeongsan, South Korea
| | - Mudsser Azam
- Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Safikur Rahman
- Department of Medical Biotechnology, Yeungnam University, Gyeongsan, South Korea
| | - Angham M S Almigeiti
- Department of Medical Biotechnology, Yeungnam University, Gyeongsan, South Korea
| | - Duk Hwan Choi
- Department of Medical Biotechnology, Yeungnam University, Gyeongsan, South Korea
| | - Eun Ju Lee
- Department of Medical Biotechnology, Yeungnam University, Gyeongsan, South Korea
| | | | - Inho Choi
- Department of Medical Biotechnology, Yeungnam University, Gyeongsan, South Korea
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158
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Calapai G, Bonina F, Bonina A, Rizza L, Mannucci C, Arcoraci V, Laganà G, Alibrandi A, Pollicino C, Inferrera S, Alecci U. A Randomized, Double-Blinded, Clinical Trial on Effects of a Vitis vinifera Extract on Cognitive Function in Healthy Older Adults. Front Pharmacol 2017; 8:776. [PMID: 29163162 PMCID: PMC5671585 DOI: 10.3389/fphar.2017.00776] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 10/13/2017] [Indexed: 01/06/2023] Open
Abstract
Introduction: Gradual population aging is creating a new set of needs in the general population. Memory capacity decreases with age, and memory deficits are considered an early symptom of Alzheimer’s Disease (AD), one of the most prevalent cognitive disorders in older people. Numerous studies have shown that grape polyphenolic compounds (GPs) are able to attenuate cognitive impairment and reduce brain lesions in experimental AD animal models. These GP effects are associated with improvement in brain antioxidant status and prevention of free radical-induced neuronal damage. We designed a randomized, double-blind, placebo-controlled clinical trial to investigate the potential beneficial effects of a Vitis vinifera-based dietary supplement on cognitive function and neuropsychological status in healthy older adults. Methods: One-hundred eleven subjects were recruited and randomly divided in two groups: one group received the V. vinifera-based dietary supplement Cognigrape® for 12 weeks (250 mg/day) and the second group received placebo over the same period of time. Before and after the end of the supplementation period, cognitive function and neuropsychological status were evaluated using the Mini-Mental State Examination (MMSE), Beck Depression Inventory (BDI), Hamilton Anxiety Rating Scale (HARS), and Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) evaluations. Results: MMSE scores were significantly improved after supplementation with Cognigrape® in comparison with baseline levels (p < 0.0001) and placebo (r = 0.59, 0.95% CI 0.11, 1.22; p < 0.0001). Cognigrape® supplementation produced a significant reduction in BDI (-15.8%) and HARS (-24.9%) scores with respect to baseline levels (p < 0.0001) and placebo (p < 0.0001 for BDI and p < 0.05 for HARS). RBANS total score was significantly improved by Cognigrape® with respect to baseline levels and placebo (r = 0.55, 0.95% CI 0.48, 6.07; p < 0.0001). The comparison with the placebo revealed improvements in several parameters among participants receiving Cognigrape®: attention (p < 0.001); language (p < 0.05); immediate memory (p < 0.0001); and delayed memory (p < 0.0001). Visuospatial/constructional abilities were not modified. During the study, no adverse effects were detected. Conclusion: The results show that 12 weeks of Cognigrape® supplementation is safe, can improve physiological cognitive profiles, and can concurrently ameliorate negative neuropsychological status in healthy older adults.
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Affiliation(s)
- Gioacchino Calapai
- Department of Biomedical, Dental Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy
| | - Francesco Bonina
- Department of Drug Sciences, University of Catania, Catania, Italy
| | | | - Luisa Rizza
- Bionap srl, R&D Contrada Fureria, Belpasso, Italy
| | - Carmen Mannucci
- Department of Biomedical, Dental Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy
| | - Vincenzo Arcoraci
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - Germana Laganà
- Italian College of General Practitioners and Primary Care, Florence, Italy
| | - Angela Alibrandi
- Department of Economics, Unit of Statistical and Mathematical Sciences, University of Messina, Messina, Italy
| | - Concetta Pollicino
- Department of Biomedical, Dental Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy
| | - Santi Inferrera
- Italian College of General Practitioners and Primary Care, Florence, Italy
| | - Umberto Alecci
- Italian College of General Practitioners and Primary Care, Florence, Italy
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159
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Ayaz M, Junaid M, Ullah F, Subhan F, Sadiq A, Ali G, Ovais M, Shahid M, Ahmad A, Wadood A, El-Shazly M, Ahmad N, Ahmad S. Anti-Alzheimer's Studies on β-Sitosterol Isolated from Polygonum hydropiper L. Front Pharmacol 2017; 8:697. [PMID: 29056913 PMCID: PMC5635809 DOI: 10.3389/fphar.2017.00697] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 09/19/2017] [Indexed: 12/22/2022] Open
Abstract
The family Polygonaceae is known for its traditional use in the management of various neurological disorders including Alzheimer's disease (AD). In search of new anti-AD drugs, β-sitosterol isolated from Polygonum hydropiper was subjected to in vitro, in vivo, behavioral and molecular docking studies to confirm its possibility as a potential anti-Alzheimer's agent. The in vitro AChE, BChE inhibitory potentials of β-sitosterol were investigated following Ellman's assay. The antioxidant activity was tested using DPPH, ABTS and H2O2 assays. Behavioral studies were performed on a sub-strain of transgenic mice using shallow water maze (SWM), Y-maze and balance beam tests. β-sitosterol was tested for in vivo inhibitory potentials against cholinesterase's and free radicals in the frontal cortex (FC) and hippocampus (HC). The molecular docking study was performed to predict the binding mode of β-sitosterol in the active sites of AChE and BChE as inhibitor. Considerable in vitro and in vivo cholinesterase inhibitory effects were observed in the β-sitosterol treated groups. β-sitosterol exhibited an IC50 value of 55 and 50 μg/ml against AChE and BChE respectively. Whereas, the activity of these enzymes were significantly low in FC and HC homogenates of transgenic animals. Molecular docking studies also support the binding of β-sitosterol with the target enzyme and further support the in vitro and in vivo results. In the antioxidant assays, the IC50 values were observed as 140, 120, and 280 μg/ml in the DPPH, ABTS and H2O2 assays respectively. The free radicals load in the brain tissues was significantly declined in the β-sitosterol treated animals as compared to the transgenic-saline treated groups. In the memory assessment and coordination tasks including SWM, Y-maze and balance beam tests, β-sitosterol treated transgenic animals showed gradual improvement in working memory, spontaneous alternation behavior and motor coordination. These results conclude that β-sitosterol is a potential compound for the management of memory deficit disorders like AD.
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Affiliation(s)
- Muhammad Ayaz
- Department of Pharmacy, University of Malakand, Chakdara, Pakistan
| | - Muhammad Junaid
- Department of Pharmacy, University of Malakand, Chakdara, Pakistan
| | - Farhat Ullah
- Department of Pharmacy, University of Malakand, Chakdara, Pakistan
| | - Fazal Subhan
- Department of Pharmacy, University of Peshawar, Peshawar, Pakistan
| | - Abdul Sadiq
- Department of Pharmacy, University of Malakand, Chakdara, Pakistan
| | - Gowhar Ali
- Department of Pharmacy, University of Peshawar, Peshawar, Pakistan
| | - Muhammad Ovais
- Cancer Biology Lab, Department of Biotechnology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Muhammad Shahid
- Department of Pharmacy, University of Peshawar, Peshawar, Pakistan
- Department of Pharmacy, Sarhad University of Science and Information Technology, Peshawar, Pakistan
| | - Ashfaq Ahmad
- Department of Pharmacy, University of Malakand, Chakdara, Pakistan
- Department of Pharmacy, Sarhad University of Science and Information Technology, Peshawar, Pakistan
| | - Abdul Wadood
- Department of Biochemistry, Abdul Wali Khan University, Mardan, Pakistan
| | - Mohamed El-Shazly
- Department of Pharmacognosy and Natural Products Chemistry, Faculty of Pharmacy, Ain-Shams University, Cairo, Egypt
| | - Nisar Ahmad
- Department of Pharmacy, University of Peshawar, Peshawar, Pakistan
| | - Sajjad Ahmad
- Department of Pharmacy, University of Malakand, Chakdara, Pakistan
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160
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Yamamoto N, Shibata M, Ishikuro R, Tanida M, Taniguchi Y, Ikeda-Matsuo Y, Sobue K. Epigallocatechin gallate induces extracellular degradation of amyloid β-protein by increasing neprilysin secretion from astrocytes through activation of ERK and PI3K pathways. Neuroscience 2017; 362:70-78. [DOI: 10.1016/j.neuroscience.2017.08.030] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 08/08/2017] [Accepted: 08/15/2017] [Indexed: 01/29/2023]
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161
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Elufioye TO, Berida TI, Habtemariam S. Plants-Derived Neuroprotective Agents: Cutting the Cycle of Cell Death through Multiple Mechanisms. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE : ECAM 2017; 2017:3574012. [PMID: 28904554 PMCID: PMC5585568 DOI: 10.1155/2017/3574012] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 07/14/2017] [Accepted: 07/18/2017] [Indexed: 12/11/2022]
Abstract
Neuroprotection is the preservation of the structure and function of neurons from insults arising from cellular injuries induced by a variety of agents or neurodegenerative diseases (NDs). The various NDs including Alzheimer's, Parkinson's, and Huntington's diseases as well as amyotropic lateral sclerosis affect millions of people around the world with the main risk factor being advancing age. Each of these diseases affects specific neurons and/or regions in the brain and involves characteristic pathological and molecular features. Hence, several in vitro and in vivo study models specific to each disease have been employed to study NDs with the aim of understanding their underlying mechanisms and identifying new therapeutic strategies. Of the most prevalent drug development efforts employed in the past few decades, mechanisms implicated in the accumulation of protein-based deposits, oxidative stress, neuroinflammation, and certain neurotransmitter deficits such as acetylcholine and dopamine have been scrutinized in great detail. In this review, we presented classical examples of plant-derived neuroprotective agents by highlighting their structural class and specific mechanisms of action. Many of these natural products that have shown therapeutic efficacies appear to be working through the above-mentioned key multiple mechanisms of action.
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Affiliation(s)
| | - Tomayo Ireti Berida
- Department of Pharmacognosy, Faculty of Pharmacy, University of Ibadan, Ibadan, Nigeria
| | - Solomon Habtemariam
- Pharmacognosy Research Laboratories and Herbal Analysis Services, University of Greenwich, Chatham-Maritime, Kent ME4 4TB, UK
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162
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Renno WM, Benov L, Khan KM. Possible role of antioxidative capacity of (-)-epigallocatechin-3-gallate treatment in morphological and neurobehavioral recovery after sciatic nerve crush injury. J Neurosurg Spine 2017; 27:593-613. [PMID: 28777065 DOI: 10.3171/2016.10.spine16218] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE This study examined the capacity of the major polyphenolic green tea extract (-)-epigallocatechin-3-gallate (EGCG) to suppress oxidative stress and stimulate the recovery and prompt the regeneration of sciatic nerve after crush injury. METHODS Adult male Wistar rats were randomly assigned to one of 4 groups: 1) Naïve, 2) Sham (sham injury, surgical control group), 3) Crush (sciatic nerve crush injury treated with saline), and 4) Crush+EGCG (sciatic nerve crush injury treated with intraperitoneally administered EGCG, 50 mg/kg). All animals were tested for motor and sensory neurobehavioral parameters throughout the study. Sciatic nerve and spinal cord tissues were harvested and processed for morphometric and stereological analysis. For the biochemical assays, the time points were Day 1, Day 7, Day 14, and Day 28 after nerve injury. RESULTS After sciatic nerve crush injury, the EGCG-treated animals (Crush+EGCG group) showed significantly better recovery of foot position and toe spread and 50% greater improvement in motor recovery than the saline-treated animals (Crush group). The Crush+EGCG group displayed an early hopping response at the beginning of the 3rd week postinjury. Animals in the Crush+EGCG group also showed a significant reduction in mechanical allodynia and hyperalgesia latencies and significant improvement in recovery from nociception deficits in both heat withdrawal and tail flick withdrawal latencies compared with the Crush group. In both the Crush+EGCG and Crush groups, quantitative evaluation revealed significant morphological evidence of neuroregeneration according to the following parameters: mean cross-sectional area of axons, myelin thickness in the sciatic nerve (from Week 4 to Week 8), increase of myelin basic protein concentration and gene expression in both the injured sciatic nerve and spinal cord, and fiber diameter to axon diameter ratio and myelin thickness to axon diameter ratio at Week 2 after sciatic nerve injury. However, the axon area remained much smaller in both the Crush+EGCG and Crush groups compared with the Sham and Naïve groups. The number of axons per unit area was significantly decreased in the Crush+EGCG and Crush groups compared with controls. Sciatic nerve injury produced generalized oxidative stress manifested as a significant increase of isoprostanes in the urine and decrease of the total antioxidant capacity (TAC) of the blood from Day 7 until Day 14. EGCG-treated rats showed significantly less increase of isoprostanes than saline-treated animals and also showed full recovery of TAC levels by Day 14 after nerve injury. In spinal cord tissue analysis, EGCG-treated animals showed induced glutathione reductase and suppressed induction of heme oxygenase 1 gene expression compared with nontreated animals. CONCLUSIONS EGCG treatment suppressed the crush-induced production of isoprostanes and stimulated the recovery of the TAC and was associated with remarkable alleviation of motor and sensory impairment and significant histomorphological evidence of neuronal regeneration following sciatic nerve crush injury in rats. The findings of this study suggest that EGCG can be used as an adjunctive therapeutic remedy for nerve injury. However, further investigations are needed to establish the antioxidative mechanism involved in the regenerative process after nerve injury. Only upregulation of glutathione reductase supports the idea that EGCG is acting indirectly via induction of enzymes or transcription factors.
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Affiliation(s)
| | - Ludmil Benov
- Biochemistry, Faculty of Medicine, Kuwait University, Safat, Kuwait
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163
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Ding ML, Ma H, Man YG, Lv HY. Protective effects of a green tea polyphenol, epigallocatechin-3-gallate, against sevoflurane-induced neuronal apoptosis involve regulation of CREB/BDNF/TrkB and PI3K/Akt/mTOR signalling pathways in neonatal mice. Can J Physiol Pharmacol 2017; 95:1396-1405. [PMID: 28679060 DOI: 10.1139/cjpp-2016-0333] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Epigallocatechin-3-gallate (EGCG), a polyphenol in green tea, is an effective antioxidant and possesses neuroprotective effects. Brain-derived neurotrophic factor (BDNF) and cyclic AMP response element-binding protein (CREB) are crucial for neurogenesis and synaptic plasticity. In this study, we aimed to assess the protective effects of EGCG against sevoflurane-induced neurotoxicity in neonatal mice. Distinct groups of C57BL/6 mice were given EGCG (25, 50, or 75 mg/kg body weight) from postnatal day 3 (P3) to P21 and were subjected to sevoflurane (3%; 6 h) exposure on P7. EGCG significantly inhibited sevoflurane-induced neuroapoptosis as determined by Fluoro-Jade B staining and terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL). Increased levels of cleaved caspase-3, downregulated Bad and Bax, and significantly enhanced Bcl-2, Bcl-xL, xIAP, c-IAP-1, and survivin expression were observed. EGCG induced activation of the PI3K/Akt pathway as evidenced by increased Akt, phospho-Akt, GSK-3β, phospho-GSK-3β, and mTORc1 levels. Sevoflurane-mediated downregulation of cAMP/CREB and BDNF/TrkB signalling was inhibited by EGCG. Reverse transcription PCR analysis revealed enhanced BDNF and TrkB mRNA levels upon EGCG administration. Improved performance of mice in Morris water maze tests suggested enhanced learning and memory. The study indicates that EGCG was able to effectively inhibit sevoflurane-induced neurodegeneration and improve learning and memory retention of mice via activation of CREB/BDNF/TrkB-PI3K/Akt signalling.
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Affiliation(s)
- Mei-Li Ding
- a Department of Pediatrics, Shandong Jining No. 1 People's Hospital, Shandong 272011, China
| | - Hui Ma
- b Department of Neurosurgery, Shandong Jining No. 1 People's Hospital, Shandong 272011, China
| | - Yi-Gang Man
- a Department of Pediatrics, Shandong Jining No. 1 People's Hospital, Shandong 272011, China
| | - Hong-Yan Lv
- a Department of Pediatrics, Shandong Jining No. 1 People's Hospital, Shandong 272011, China
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164
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The efficacy of Epigallocatechin-3-gallate (green tea) in the treatment of Alzheimer's disease: an overview of pre-clinical studies and translational perspectives in clinical practice. Infect Agent Cancer 2017. [PMID: 28642806 PMCID: PMC5477123 DOI: 10.1186/s13027-017-0145-6] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder and the most common form of dementia characterized by cognitive and memory impairment. One of the mechanism involved in the pathogenesis of AD, is the oxidative stress being involved in AD's development and progression. In addition, several studies proved that chronic viral infections, mainly induced by Human herpesvirus 1 (HHV-1), Cytomegalovirus (CMV), Human herpesvirus 2 (HHV-2), and Hepatitis C virus (HCV) could be responsible for AD's neuropathology. Despite the large amount of data regarding the pathogenesis of Alzheimer's disease (AD), a very limited number of therapeutic drugs and/or pharmacological approaches, have been developed so far. It is important to underline that, in recent years, natural compounds, due their antioxidants and anti-inflammatory properties have been largely studied and identified as promising agents for the prevention and treatment of neurodegenerative diseases, including AD. The ester of epigallocatechin and gallic acid, (-)-Epigallocatechin-3-Gallate (EGCG), is the main and most significantly bioactive polyphenol found in solid green tea extract. Several studies showed that this compound has important anti-inflammatory and antiatherogenic properties as well as protective effects against neuronal damage and brain edema. To date, many studies regarding the potential effects of EGCG in AD's treatment have been reported in literature. The purpose of this review is to summarize the in vitro and in vivo pre-clinical studies on the use of EGCG in the prevention and the treatment of AD as well as to offer new insights for translational perspectives into clinical practice.
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165
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Hou H, Habib A, Zi D, Tian K, Tian J, Giunta B, Sawmiller D, Tan J. Low-Density Lipoprotein Receptor-Related Protein-1 (LRP1) C4408R Mutant Promotes Amyloid Precursor Protein (APP) α-Cleavage in Vitro. Neuromolecular Med 2017; 19:300-308. [PMID: 28612181 DOI: 10.1007/s12017-017-8446-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 06/06/2017] [Indexed: 12/30/2022]
Abstract
Previous studies have demonstrated that the low-density lipoprotein receptor-related protein-1 (LRP1) plays conflicting roles in Alzheimer's disease (AD) pathogenesis, clearing β-amyloid (Aβ) from the brain while also enhancing APP endocytosis and resultant amyloidogenic processing. We have recently discovered that co-expression of mutant LRP1 C-terminal domain (LRP1-CT C4408R) with Swedish mutant amyloid precursor protein (APPswe) in Chinese hamster ovary (CHO) cells decreases Aβ production, while also increasing sAPPα and APP α-C-terminal fragment (α-CTF), compared with CHO cells expressing APPswe alone. Surprisingly, the location of this mutation on LRP1 corresponded with the α-secretase cleavage site of APP. Further experimentation confirmed that in CHO cells expressing APPswe or wild-type APP (APPwt), co-expression of LRP1-CT C4408R decreases Aβ and increases sAPPα and α-CTF compared with co-expression of wild-type LRP1-CT. In addition, LRP1-CT C4408R enhanced the unglycosylated form of LRP1-CT and reduced APP endocytosis as determined by flow cytometry. This finding identifies a point mutation in LRP1 which slows LRP1-CT-mediated APP endocytosis and amyloidogenic processing, while enhancing APP α-secretase cleavage, thus demonstrating a potential novel target for slowing AD pathogenesis.
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Affiliation(s)
- Huayan Hou
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Morsani College of Medicine, University of South Florida, Tampa, FL, 33613, USA
| | - Ahsan Habib
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Morsani College of Medicine, University of South Florida, Tampa, FL, 33613, USA
| | - Dan Zi
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Morsani College of Medicine, University of South Florida, Tampa, FL, 33613, USA.,Department of Obstetrics and Gynecology, Guizhou Medical University, Guiyang, 55004, China
| | - Kathy Tian
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Morsani College of Medicine, University of South Florida, Tampa, FL, 33613, USA
| | - Jun Tian
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Morsani College of Medicine, University of South Florida, Tampa, FL, 33613, USA
| | - Brian Giunta
- Neuroimmunology Laboratory, Department of Psychiatry and Behavioral Neurosciences, Morsani College of Medicine, University of South Florida, Tampa, FL, 33613, USA
| | - Darrell Sawmiller
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Morsani College of Medicine, University of South Florida, Tampa, FL, 33613, USA.
| | - Jun Tan
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Morsani College of Medicine, University of South Florida, Tampa, FL, 33613, USA
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166
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Halawany AME, Sayed NSE, Abdallah HM, Dine RSE. Protective effects of gingerol on streptozotocin-induced sporadic Alzheimer's disease: emphasis on inhibition of β-amyloid, COX-2, alpha-, beta - secretases and APH1a. Sci Rep 2017; 7:2902. [PMID: 28588301 PMCID: PMC5460182 DOI: 10.1038/s41598-017-02961-0] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 04/26/2017] [Indexed: 12/27/2022] Open
Abstract
Gingerol is a major dietary compound that occurs in several plants belonging to the Zingiberaceae family. In the current study, the protective effect of gingerol on STZ-induced sporadic Alzheimer's disease (SAD) was determined. Gingerol was isolated from the seeds of Aframomum melegueta K. Schum and tested at doses of 10 and 20 mg/kgbwt for its possible effect on the SAD model in mice, using celecoxib (30 mg/kg bwt) as a reference standard. The curative effects of gingerol were assessed through measurement of β-amyloid (Aβ-42), α-, β- secretases, APH1a and COX-2 levels. In addition, improvement in the cognitive deficit in mice after treatment was confirmed using the water maze and Y-maze with intra-maze cues. Gingerol improved the cognitive and behavioral impairment and AD-like pathology in streptozotocin model mice. These beneficial effects occurred with an increase in α-secretase activity and a decrease in cerebral Aβ-42, β- secretase, APH1a activity and COX-2-linked neuro-inflammation.
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Affiliation(s)
- Ali M El Halawany
- Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt
| | - Nesrine S El Sayed
- Department of Pharmacology &Toxicology, Faculty of pharmacy, Cairo University, 11562, Cairo, Egypt.,Department of Pharmacology &Toxicology, Faculty of pharmacy & Biotechnology, German University in Cairo, 11835, Cairo, Egypt
| | - Hossam M Abdallah
- Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt. .,Department of Natural Products, Faculty of Pharmacy, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
| | - Riham Salah El Dine
- Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt
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167
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Franco R, Martínez-Pinilla E. Chemical rules on the assessment of antioxidant potential in food and food additives aimed at reducing oxidative stress and neurodegeneration. Food Chem 2017; 235:318-323. [PMID: 28554642 DOI: 10.1016/j.foodchem.2017.05.040] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 04/03/2017] [Accepted: 05/08/2017] [Indexed: 01/01/2023]
Abstract
Antioxidants (aOXs) enlarge the useful life of products consumed by humans. Life requires oxidation of glucose/fatty acids and, therefore, "antioxidant" becomes an oxymoron when trying to define benefits in organisms living in an oxygen-rich atmosphere. According to basic physico-chemical principles, the in vivo aOX potential of food supplements is negligible when compared with the main aOX molecules in the animal Kingdom: glucose and fatty acids. Thus, the aOX assumption to improve life-quality is misleading as oxidative stress and exacerbation occur when oxidant foods (e.g. fava beans) are consumed. Evolution produced potent detoxification mechanisms to handle these situations. When age/genetic/environmental factors negatively impact on detoxification mechanisms, nutrition helps on providing metabolites/precursors needed for boosting innate resources. Ambiguous techniques that attempt to measure in vivo aOX power, should give way to measuring the level of supplements and their metabolites in body fluids/tissues, and to measure the efficacy on antioxidant boosting REDOX pathways.
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Affiliation(s)
- Rafael Franco
- CIBERNED, Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Instituto de Salud Carlos III, Madrid, Spain; Institute of Biomedicine of the University of Barcelona (IBUB), Barcelona, Spain; Molecular Neurobiology Laboratory, Department of Biochemistry and Molecular Biomedicine, Faculty of Biology, University of Barcelona, Barcelona, Spain.
| | - Eva Martínez-Pinilla
- Instituto de Neurociencias del Principado de Asturias (INEUROPA), Departamento de Morfología y Biología Celular, Facultad de Medicina, Universidad de Oviedo, Asturias, Spain.
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168
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Omar SH. Biophenols pharmacology against the amyloidogenic activity in Alzheimer’s disease. Biomed Pharmacother 2017; 89:396-413. [DOI: 10.1016/j.biopha.2017.02.051] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 02/15/2017] [Accepted: 02/15/2017] [Indexed: 02/01/2023] Open
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169
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Inhibition of amyloid oligomerization into different supramolecular architectures by small molecules: mechanistic insights and design rules. Future Med Chem 2017; 9:797-810. [DOI: 10.4155/fmc-2017-0026] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Protein misfolding and aggregation have been associated with several human disorders, including Alzheimer’s, Parkinson’s and Huntington’s diseases, as well as senile systemic amyloidosis and Type II diabetes. However, there is no current disease-modifying therapy available for the treatment of these disorders. In spite of extensive academic, pharmaceutical, medicinal and clinical research, a complete mechanistic model for this family of diseases is still lacking. In this review, we primarily discuss the different types of small molecular entities which have been used for the inhibition of the aggregation process of different amyloidogenic proteins under diseased conditions. These include small peptides, polyphenols, inositols, quinones and their derivatives, and metal chelator molecules. In recent years, these groups of molecules have been extensively studied using in vitro, in vivo and computational models to understand their mechanism of action and common structural features underlying the process of inhibition. A salient feature found to be instrumental in the process of inhibition is the balance between the aromatic unit that functions as the amyloid recognition unit and the hydrophilic amyloid breaker unit. The establishment of structure–function relationship for amyloid-modifying therapies by the various functional entities should serve as an important step toward the development of efficient therapeutics.
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170
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Velander P, Wu L, Henderson F, Zhang S, Bevan DR, Xu B. Natural product-based amyloid inhibitors. Biochem Pharmacol 2017; 139:40-55. [PMID: 28390938 DOI: 10.1016/j.bcp.2017.04.004] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 04/03/2017] [Indexed: 11/26/2022]
Abstract
Many chronic human diseases, including multiple neurodegenerative diseases, are associated with deleterious protein aggregates, also called protein amyloids. One common therapeutic strategy is to develop protein aggregation inhibitors that can slow down, prevent, or remodel toxic amyloids. Natural products are a major class of amyloid inhibitors, and several dozens of natural product-based amyloid inhibitors have been identified and characterized in recent years. These plant- or microorganism-extracted compounds have shown significant therapeutic potential from in vitro studies as well as in vivo animal tests. Despite the technical challenges of intrinsic disordered or partially unfolded amyloid proteins that are less amenable to characterizations by structural biology, a significant amount of research has been performed, yielding biochemical and pharmacological insights into how inhibitors function. This review aims to summarize recent progress in natural product-based amyloid inhibitors and to analyze their mechanisms of inhibition in vitro. Major classes of natural product inhibitors and how they were identified are described. Our analyses comprehensively address the molecular interactions between the inhibitors and relevant amyloidogenic proteins. These interactions are delineated at molecular and atomic levels, which include covalent, non-covalent, and metal-mediated mechanisms. In vivo animal studies and clinical trials have been summarized as an extension. To enhance natural product bioavailability in vivo, emerging work using nanocarriers for delivery has also been described. Finally, issues and challenges as well as future development of such inhibitors are envisioned.
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Affiliation(s)
- Paul Velander
- Department of Biochemistry, Virginia Polytechnic Institute & State University, Blacksburg, VA 24061, USA
| | - Ling Wu
- Department of Biochemistry, Virginia Polytechnic Institute & State University, Blacksburg, VA 24061, USA
| | - Frances Henderson
- Department of Biochemistry, Virginia Polytechnic Institute & State University, Blacksburg, VA 24061, USA
| | - Shijun Zhang
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - David R Bevan
- Department of Biochemistry, Virginia Polytechnic Institute & State University, Blacksburg, VA 24061, USA; Center for Drug Discovery, Virginia Polytechnic Institute & State University, Blacksburg, VA 24061, USA; School of Neuroscience, Virginia Polytechnic Institute & State University, Blacksburg, VA 24061, USA
| | - Bin Xu
- Department of Biochemistry, Virginia Polytechnic Institute & State University, Blacksburg, VA 24061, USA; Center for Drug Discovery, Virginia Polytechnic Institute & State University, Blacksburg, VA 24061, USA; School of Neuroscience, Virginia Polytechnic Institute & State University, Blacksburg, VA 24061, USA; Translational Obesity Research Center, Virginia Polytechnic Institute & State University, Blacksburg, VA 24061, USA.
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171
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Sawmiller D, Li S, Mori T, Habib A, Rongo D, Delic V, Bradshaw PC, Shytle RD, Sanberg C, Bickford P, Tan J. Beneficial effects of a pyrroloquinolinequinone-containing dietary formulation on motor deficiency, cognitive decline and mitochondrial dysfunction in a mouse model of Alzheimer's disease. Heliyon 2017; 3:e00279. [PMID: 28413833 PMCID: PMC5384415 DOI: 10.1016/j.heliyon.2017.e00279] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 02/27/2017] [Accepted: 03/23/2017] [Indexed: 11/21/2022] Open
Abstract
Alzheimer’s disease (AD), a progressive neurodegenerative disorder, is linked to oxidative stress, altered amyloid precursor protein (APP) proteolysis, tau hyperphosphorylation and the accumulation of amyloid-β (Aβ) plaques and neurofibrillary tangles (NFT). A growing body of evidence suggests that mitochondrial dysfunction can be a key promoter of all of these pathologies and predicts that restoration of mitochondrial function might be a potential therapeutic strategy for AD. Therefore, in the present study, we tested the beneficial effect of a nutraceutical formulation Nutrastem II (Nutra II), containing NT020 (a mitochondrial restorative and antioxidant proprietary formulation) and pyrroloquinolinequinone (PQQ, a stimulator of mitochondria biogenesis) in 5XFAD transgenic mice. Animals were fed Nutra II for 12 weeks, starting at 3 months of age, after which behavioral and neuropathological endpoints were determined. The data from behavioral test batteries clearly revealed that dietary supplementation of Nutra II effectively ameliorated the motor deficiency and cognitive impairment of 5XFAD mice. In addition, Nutra II also protected mitochondrial function in 5XFAD mice brain, as evidenced by declined ROS levels and membrane hyperpolarization, together with elevated ATP levels and respiratory states. Interestingly, while Nutra II treatment only slightly reduced soluble Aβ42 levels, this formulation significantly impacted tau metabolism, as shown by reduced total and phosphorylated tau levels of 5XFAD mouse brain. Taken together, these preclinical findings confirm that mitochondrial function may be a key treatment target for AD and that Nutra II should be further investigated as a potential candidate for AD therapy.
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Affiliation(s)
- Darrell Sawmiller
- James A. Haley Veteran’s Administration Hospital, Tampa, Florida, United States
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
- Corresponding authors.
| | - Song Li
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
- Center for Translational Research of Neurology Diseases, First Affiliated Hospital, Dalian Medical University, Dalian, China
- Corresponding authors.
| | - Takashi Mori
- Department of Biomedical Sciences and Pathology, Saitama Medical Center and Saitama Medical University, Kawagoe, Saitama, Japan
| | - Ahsan Habib
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
| | - David Rongo
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
| | - Vedad Delic
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, Florida, United States
| | - Patrick C. Bradshaw
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, Florida, United States
| | - R. Douglas Shytle
- Department of Neurosurgery and Brain Repair, Center for Aging and Brain Repair, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
| | - Cyndy Sanberg
- Saneron CCEL Therapeutics, Inc., Tampa, Florida, United States
| | - Paula Bickford
- James A. Haley Veteran’s Administration Hospital, Tampa, Florida, United States
- Department of Neurosurgery and Brain Repair, Center for Aging and Brain Repair, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
| | - Jun Tan
- James A. Haley Veteran’s Administration Hospital, Tampa, Florida, United States
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
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172
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Liu H, Yu L, Dong X, Sun Y. Synergistic effects of negatively charged hydrophobic nanoparticles and (−)-epigallocatechin-3-gallate on inhibiting amyloid β-protein aggregation. J Colloid Interface Sci 2017; 491:305-312. [DOI: 10.1016/j.jcis.2016.12.038] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 12/15/2016] [Accepted: 12/16/2016] [Indexed: 10/20/2022]
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173
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Omar SH, Scott CJ, Hamlin AS, Obied HK. The protective role of plant biophenols in mechanisms of Alzheimer's disease. J Nutr Biochem 2017; 47:1-20. [PMID: 28301805 DOI: 10.1016/j.jnutbio.2017.02.016] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Revised: 01/03/2017] [Accepted: 02/16/2017] [Indexed: 12/31/2022]
Abstract
Self-assembly of amyloid beta peptide (Aβ) into the neurotoxic oligomers followed by fibrillar aggregates is a defining characteristic of Alzheimer's disease (AD). Several lines of proposed hypotheses have suggested the mechanism of AD pathology, though the exact pathophysiological mechanism is not yet elucidated. The poor understanding of AD and multitude of adverse responses reported from the current synthetic drugs are the leading cause of failure in the drug development to treat or halt the progression of AD and mandate the search for safer and more efficient alternatives. A number of natural compounds have shown the ability to prevent the formation of the toxic oligomers and disrupt the aggregates, thus attracted much attention. Referable to the abundancy and multitude of pharmacological activities of the plant active constituents, biophenols that distinguish them from the other phytochemicals as a natural weapon against the neurodegenerative disorders. This review provides a critical assessment of the current literature on in vitro and in vivo mechanistic activities of biophenols associated with the prevention and treatment of AD. We have contended the need for more comprehensive approaches to evaluate the anti-AD activity of biophenols at various pathologic levels and to assess the current evidences. Consequently, we highlighted the various problems and challenges confronting the AD research, and offer recommendations for future research.
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Affiliation(s)
- Syed H Omar
- School of Biomedical Sciences, Faculty of Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia; Graham Centre for Agricultural Innovation, Charles Sturt University, Wagga Wagga, NSW 2678, Australia.
| | - Christopher J Scott
- School of Biomedical Sciences, Faculty of Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia; Graham Centre for Agricultural Innovation, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
| | - Adam S Hamlin
- School of Science & Technology, University of New England, Armidale, NSW 2351, Australia
| | - Hassan K Obied
- School of Biomedical Sciences, Faculty of Sciences, Charles Sturt University, Wagga Wagga, NSW 2678, Australia; Graham Centre for Agricultural Innovation, Charles Sturt University, Wagga Wagga, NSW 2678, Australia
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174
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Velusamy T, Panneerselvam AS, Purushottam M, Anusuyadevi M, Pal PK, Jain S, Essa MM, Guillemin GJ, Kandasamy M. Protective Effect of Antioxidants on Neuronal Dysfunction and Plasticity in Huntington's Disease. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:3279061. [PMID: 28168008 PMCID: PMC5266860 DOI: 10.1155/2017/3279061] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 11/09/2016] [Accepted: 12/05/2016] [Indexed: 01/08/2023]
Abstract
Huntington's disease (HD) is characterised by movement disorders, cognitive impairments, and psychiatric problems. The abnormal generation of reactive oxygen species and the resulting oxidative stress-induced mitochondrial damage in neurons upon CAG mutations in the HTT gene have been hypothesized as the contributing factors of neurodegeneration in HD. The potential use of antioxidants against free radical toxicity has been an emerging field in the management of ageing and many neurodegenerative disorders. Neural stem cells derived adult neurogenesis represents the regenerative capacity of the adult brain. The process of adult neurogenesis has been implicated in the cognitive functions of the brain and is highly modulated positively by different factors including antioxidants. The supportive role of antioxidants to reduce the severity of HD via promoting the functional neurogenesis and neuroprotection in the pathological adult brain has great promise. This review comprehends the recent studies describing the therapeutic roles of antioxidants in HD and other neurologic disorders and highlights the scope of using antioxidants to promote adult neurogenesis in HD. It also advocates a new line of research to delineate the mechanisms by which antioxidants promote adult neurogenesis in HD.
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Affiliation(s)
- Thirunavukkarasu Velusamy
- Department of Biotechnology, Bharathiar University, Coimbatore, Tamil Nadu, India
- DBT Ramalingaswami Re-Entry Fellowship Programme, Department of Biotechnology (DBT), New Delhi, India
| | - Archana S. Panneerselvam
- Laboratory of Stem Cells and Neuroregeneration, Department of Animal Science, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India
| | - Meera Purushottam
- Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, Karnataka, India
| | - Muthuswamy Anusuyadevi
- Molecular Gerontology Laboratory, Department of Biochemistry, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India
| | - Pramod Kumar Pal
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, Karnataka, India
| | - Sanjeev Jain
- Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, Karnataka, India
| | - Musthafa Mohamed Essa
- Department of Food Science and Nutrition, CAMS, Sultan Qaboos University, Muscat, Oman
| | - Gilles J. Guillemin
- Neuroinflammation Group, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Mahesh Kandasamy
- Laboratory of Stem Cells and Neuroregeneration, Department of Animal Science, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India
- UGC-Faculty Recharge Program (UGC-FRP), University Grant Commission, New Delhi, India
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175
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Neuroprotective Effects of Aged Garlic Extract on Cognitive Dysfunction and Neuroinflammation Induced by β-Amyloid in Rats. Nutrients 2017; 9:nu9010024. [PMID: 28054940 PMCID: PMC5295068 DOI: 10.3390/nu9010024] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 12/05/2016] [Accepted: 12/26/2016] [Indexed: 01/08/2023] Open
Abstract
Neuroinflammation is pathological evidence of Alzheimer's disease (AD) that likely starts as a host defense response to the damaging effects of the β-amyloid (Aβ) deposits in the brain. The activation of microglia may promote the neurodegenerative process through the release of proinflammatory cytokines, such as interleukin-1β (IL-1β) and tumor necrosis factor-α (TNFα), which may lead to neuronal damage and eventual death. Aged garlic extract (AGE) has been reported to have multiple biological activities, including anti-inflammatory effects. Therefore, the objective of this study was to investigate the effect of AGE on Aβ (1-42)-induced cognitive dysfunction and neuroinflammation. Adult male Wistar rats were given AGE (125, 250, and 500 mg/kg BW, body weight), orally administered, daily for 56 days. They were then injected with 1 μL of aggregated Aβ (1-42) into the lateral ventricles; bilaterally. Seven days later, their recognition memory was evaluated using a novel object recognition (NOR) test. Then the rats were sacrificed to investigate the alteration of microglia cells, IL-1β and TNFα in the cerebral cortex and hippocampus. The results indicated that AGE at doses of 250 and 500 mg/kg BW significantly improved short-term recognition memory in cognitively impaired rats. In addition, AGE significantly minimized the inflammatory response by reducing the activation of microglia and IL-1β to the levels found in the control, which is similar to the results found in Celebrex-treated rats. In conclusion, AGE may be useful for improving the short-term recognition memory and relieve the neuroinflammation in Aβ-induced rats.
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Alzheimer's Disease: Insights from Genetic Mouse Models and Current Advances in Human IPSC-Derived Neurons. ADVANCES IN NEUROBIOLOGY 2017; 15:3-29. [PMID: 28674976 DOI: 10.1007/978-3-319-57193-5_1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Alzheimer's disease was first described in 1906 and since then tremendous efforts have been made to fully understand the disease pathology and to find a cure for this neurodegenerative disease. The diagnosis of Alzheimer's is still difficult, especially in early stages of the disease. Current treatment of Alzheimer's only ameliorates the symptoms but fails to provide a therapy. Over the last decades, animal models have been proven valuable in elucidating insights of the pathology. In vitro models using patient-derived cells are currently emerging and hold great promise in understanding the disease pathophysiology. Here, we introduce the neurobiology and genetic features of Alzheimer's and describe what we have learned from studies employing mouse models and patient-derived induced pluripotent stem cells.
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177
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Figueira I, Menezes R, Macedo D, Costa I, Nunes dos Santos C. Polyphenols Beyond Barriers: A Glimpse into the Brain. Curr Neuropharmacol 2017; 15:562-594. [PMID: 27784225 PMCID: PMC5543676 DOI: 10.2174/1570159x14666161026151545] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Revised: 08/02/2016] [Accepted: 09/28/2016] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Ageing can be simply defined as the process of becoming older, which is genetically determined but also environmentally modulated. With the continuous increase of life expectancy, quality of life during ageing has become one of the biggest challenges of developed countries. The quest for a healthy ageing has led to the extensive study of plant polyphenols with the aim to prevent age-associated deterioration and diseases, including neurodegenerative diseases. The world of polyphenols has fascinated researchers over the past decades, and in vitro, cell-based, animal and human studies have attempted to unravel the mechanisms behind dietary polyphenols neuroprotection. METHODS In this review, we compiled some of the extensive and ever-growing research in the field, highlighting some of the most recent trends in the area. RESULTS The main findings regarding polypolyphenols neuroprotective potential performed using in vitro, cellular and animal studies, as well as human trials are covered in this review. Concepts like bioavailability, polyphenols biotransformation, transport of dietary polyphenols across barriers, including the blood-brain barrier, are here explored. CONCLUSION The diversity and holistic properties of polypolyphenol present them as an attractive alternative for the treatment of multifactorial diseases, where a multitude of cellular pathways are disrupted. The underlying mechanisms of polypolyphenols for nutrition or therapeutic applications must be further consolidated, however there is strong evidence of their beneficial impact on brain function during ageing. Nevertheless, only the tip of the iceberg of nutritional and pharmacological potential of dietary polyphenols is hitherto understood and further research needs to be done to fill the gaps in pursuing a healthy ageing.
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Affiliation(s)
- Inês Figueira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras
| | - Regina Menezes
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras
| | - Diana Macedo
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras
| | - Inês Costa
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras
| | - Cláudia Nunes dos Santos
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras
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178
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Zhang M, Ren B, Chen H, Sun Y, Ma J, Jiang B, Zheng J. Molecular Simulations of Amyloid Structures, Toxicity, and Inhibition. Isr J Chem 2016. [DOI: 10.1002/ijch.201600075] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Mingzhen Zhang
- Department of Chemical and Biomolecular Engineering The University of Akron Akron OH 44325 USA
| | - Baiping Ren
- Department of Chemical and Biomolecular Engineering The University of Akron Akron OH 44325 USA
| | - Hong Chen
- Department of Chemical and Biomolecular Engineering The University of Akron Akron OH 44325 USA
| | - Yan Sun
- Department of Biochemical Engineering and Key Laboratory of Systems Bioengineering of the Ministry of Education, School of Chemical Engineering and Technology Tianjin University Tianjin 300072 P. R. China
| | - Jie Ma
- Department of Chemical and Biomolecular Engineering The University of Akron Akron OH 44325 USA
- State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 P. R. China
| | - Binbo Jiang
- Department of Chemical and Biomolecular Engineering The University of Akron Akron OH 44325 USA
- College of Chemical and Biological Engineering Zhejiang University Hangzhou Zhejiang 310027 P. R. China
| | - Jie Zheng
- Department of Chemical and Biomolecular Engineering The University of Akron Akron OH 44325 USA
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179
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Morzelle MC, Salgado JM, Telles M, Mourelle D, Bachiega P, Buck HS, Viel TA. Neuroprotective Effects of Pomegranate Peel Extract after Chronic Infusion with Amyloid-β Peptide in Mice. PLoS One 2016; 11:e0166123. [PMID: 27829013 PMCID: PMC5102433 DOI: 10.1371/journal.pone.0166123] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 10/24/2016] [Indexed: 01/01/2023] Open
Abstract
Alzheimer’s disease is a chronic and degenerative condition that had no treatment until recently. The current therapeutic strategies reduce progression of the disease but are expensive and commonly cause side effects that are uncomfortable for treated patients. Functional foods to prevent and/or treat many conditions, including neurodegenerative diseases, represent a promising field of study currently gaining attention. To this end, here we demonstrate the effects of pomegranate (Punica granatum) peel extract (PPE) regarding spatial memory, biomarkers of neuroplasticity, oxidative stress and inflammation in a mouse model of neurodegeneration. Male C57Bl/6 mice were chronically infused for 35 days with amyloid-β peptide 1–42 (Aβ) or vehicle (control) using mini-osmotic pumps. Another group, also infused with Aβ, was treated with PPE (p.o.– βA+PPE, 800 mg/kg/day). Spatial memory was evaluated in the Barnes maze. Animals treated with PPE and in the control group exhibited a reduction in failure to find the escape box, a finding that was not observed in the Aβ group. The consumption of PPE reduced amyloid plaque density, increased the expression of neurotrophin BDNF and reduced the activity of acetylcholinesterase enzyme. A reduction in lipid peroxidation and in the concentration of the pro-inflammatory cytokine TNF-α was also observed in the PPE group. No hepatic lesions were observed in animals treated with PPE. In conclusion, administration of pomegranate peel extract has neuroprotective effects involving multiple mechanisms to prevent establishment and progression of the neurodegenerative process induced by infusion with amyloid-β peptide in mice.
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Affiliation(s)
- Maressa Caldeira Morzelle
- Department of Agri-food Industry, Food and Nutrition, ‘Luiz de Queiroz’ College of Agriculture, University of São Paulo, Pádua Dias Avenue, P.O. Box. 9, 13418–900, Piracicaba, SP, Brazil
| | - Jocelem Mastrodi Salgado
- Department of Agri-food Industry, Food and Nutrition, ‘Luiz de Queiroz’ College of Agriculture, University of São Paulo, Pádua Dias Avenue, P.O. Box. 9, 13418–900, Piracicaba, SP, Brazil
| | - Milena Telles
- Graduation Course on Pharmacology, Institute of Biomedical Sciences, Universidade de São Paulo, Avenida Professor Lineu Prestes, 1524, 05508–900, São Paulo, Brazil
| | - Danilo Mourelle
- Graduation Course on Pharmacology, Institute of Biomedical Sciences, Universidade de São Paulo, Avenida Professor Lineu Prestes, 1524, 05508–900, São Paulo, Brazil
| | - Patricia Bachiega
- Department of Agri-food Industry, Food and Nutrition, ‘Luiz de Queiroz’ College of Agriculture, University of São Paulo, Pádua Dias Avenue, P.O. Box. 9, 13418–900, Piracicaba, SP, Brazil
| | - Hudson Sousa Buck
- Department of Physiological Sciences, Santa Casa de São Paulo School of Medical Sciences, R. Dr. Cesario Motta Junior, 61, 111° andar, São Paulo, SP 01221–020, Brazil
| | - Tania Araujo Viel
- Graduation Course on Pharmacology, Institute of Biomedical Sciences, Universidade de São Paulo, Avenida Professor Lineu Prestes, 1524, 05508–900, São Paulo, Brazil
- School of Arts, Sciences and Humanities, Universidade de São Paulo, Av. Arlindo Bettio, 1000, São Paulo, SP 03828–080, Brazil
- * E-mail:
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180
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Ma QP, Huang C, Cui QY, Yang DJ, Sun K, Chen X, Li XH. Meta-Analysis of the Association between Tea Intake and the Risk of Cognitive Disorders. PLoS One 2016; 11:e0165861. [PMID: 27824892 PMCID: PMC5100989 DOI: 10.1371/journal.pone.0165861] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 10/19/2016] [Indexed: 01/15/2023] Open
Abstract
Background Alzheimer’s disease is a common neurodegenerative disorder in elderly. This study was aimed to systematically evaluate the association between tea intake and the risk of cognitive disorders by meta-analysis. Methods and Findings PubMed, Embase and Wanfang databases were systematically searched and a total of 26 observational studies were included in this study. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were calculated and pooled by using fixed or random effects models according to the degree of heterogeneity. Results The overall pooled analysis indicated that tea intake could significantly reduce the risk of cognitive disorders (OR = 0.65, 95%CI = 0.58–0.73). Subgroup analyses were conducted based on study design, population, frequency of tea drinking and type of cognitive disorders. The results showed that tea drinking was significantly associated with the reduced incidence of cognitive disorders in all of subgroups based on study design and frequency of tea drinking. In particular, tea drinking was inversely associated with the risk of cognitive impairment (CoI), mild cognitive impairment (MCI), cognitive decline and ungrouped cognitive disorders. Moreover, for population subgroups, the significant association was only found in Chinese people. Conclusion Our study suggests that daily tea drinking is associated with decreased risk of CoI, MCI and cognitive decline in the elderly. However, the association between tea intake and Alzheimer’s disease remains elusive.
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Affiliation(s)
- Qing-Ping Ma
- Tea Research Institute, College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Chen Huang
- Tea Research Institute, College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Qiao-Yun Cui
- Tea Research Institute, College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Ding-Jun Yang
- Tea Research Institute, College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Kang Sun
- Tea Research Institute, College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
| | - Xuan Chen
- Tea Research Institute, College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
- * E-mail: (XHL); (XC)
| | - Xing-Hui Li
- Tea Research Institute, College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu Province, China
- * E-mail: (XHL); (XC)
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181
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Meshitsuka S, Shingaki S, Hotta M, Goto M, Kobayashi M, Ukawa Y, Sagesaka YM, Wada Y, Nojima M, Suzuki K. Phase 2 trial of daily, oral epigallocatechin gallate in patients with light-chain amyloidosis. Int J Hematol 2016; 105:295-308. [PMID: 27815860 DOI: 10.1007/s12185-016-2112-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 10/12/2016] [Accepted: 10/18/2016] [Indexed: 12/26/2022]
Abstract
Previous studies have suggested that an increase in mitochondrial reactive oxygen species may cause organ damage in patients with light-chain (AL) amyloidosis; however, this damage can be decreased by antioxidant-agent treatment. Epigallocatechin gallate (EGCG), the major natural catechin in green tea, has potent antioxidant activity. Because EGCG has recently been reported to have a favorable toxicity profile for treating amyloidosis, we sought to examine the clinical efficacy and toxicity of EGCG in patients with AL amyloidosis. Fifty-seven patients were randomly assigned to the EGCG and observation groups and observed for six months. There were no increases in grade 3-5 adverse events and EGCG therapy was well tolerated. Although a decrease in the urinary albumin level was found in the EGCG group in patients with obvious albuminuria after treatment initiation, its antioxidant activity may not be sufficient to clarify the potential effect of EGCG in patients with AL amyloidosis. Because some of the biological markers responsible for organ damage were well correlated to the level of antioxidant potential in patients' plasma, the status of oxidative stress in the blood may indicate the extent of organ damage in clinical situations.
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Affiliation(s)
- Sohsuke Meshitsuka
- Department of Hematology, Japanese Red Cross Medical Center, Tokyo, Japan. .,Center for Translational Research, The Institute of Medical Science Hospital, The University of Tokyo, 4-6-1, Shiroganedai, Minato, Tokyo, Japan.
| | - Sumito Shingaki
- Department of Hematology, Japanese Red Cross Medical Center, Tokyo, Japan
| | - Masatoshi Hotta
- Department of Radiology, National Center for Global Health and Medicine, Tokyo, Japan
| | - Miku Goto
- Laboratory for Clinical Nutrition, Department of Food and Nutrition, Faculty of Human Life, Jumonji University, Niiza, Japan
| | | | - Yuuichi Ukawa
- Central Research Institute, ITO EN, Ltd, Makinohara, Japan
| | | | - Yasuyo Wada
- Laboratory for Clinical Nutrition, Department of Food and Nutrition, Faculty of Human Life, Jumonji University, Niiza, Japan
| | - Masanori Nojima
- Center for Translational Research, The Institute of Medical Science Hospital, The University of Tokyo, 4-6-1, Shiroganedai, Minato, Tokyo, Japan
| | - Kenshi Suzuki
- Department of Hematology, Japanese Red Cross Medical Center, Tokyo, Japan
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182
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Dissecting the contribution of Staphylococcus aureus α-phenol-soluble modulins to biofilm amyloid structure. Sci Rep 2016; 6:34552. [PMID: 27708403 PMCID: PMC5052566 DOI: 10.1038/srep34552] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 09/15/2016] [Indexed: 11/23/2022] Open
Abstract
The opportunistic pathogen Staphylococcus aureus is recognized as one of the most frequent causes of biofilm-associated infections. The recently discovered phenol soluble modulins (PSMs) are small α-helical amphipathic peptides that act as the main molecular effectors of staphylococcal biofilm maturation, promoting the formation of an extracellular fibril structure with amyloid-like properties. Here, we combine computational, biophysical and in cell analysis to address the specific contribution of individual PSMs to biofilm structure. We demonstrate that despite their highly similar sequence and structure, contrary to what it was previously thought, not all PSMs participate in amyloid fibril formation. A balance of hydrophobic/hydrophilic forces and helical propensity seems to define the aggregation propensity of PSMs and control their assembly and function. This knowledge would allow to target specifically the amyloid properties of these peptides. In this way, we show that Epigallocatechin-3-gallate (EGCG), the principal polyphenol in green tea, prevents the assembly of amyloidogenic PSMs and disentangles their preformed amyloid fibrils.
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183
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Sawmiller D, Habib A, Li S, Darlington D, Hou H, Tian J, Shytle RD, Smith A, Giunta B, Mori T, Tan J. Diosmin reduces cerebral Aβ levels, tau hyperphosphorylation, neuroinflammation, and cognitive impairment in the 3xTg-AD mice. J Neuroimmunol 2016; 299:98-106. [PMID: 27725131 DOI: 10.1016/j.jneuroim.2016.08.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 08/29/2016] [Accepted: 08/31/2016] [Indexed: 02/08/2023]
Abstract
Naturally-occurring bioactive flavonoids such as diosmin significantly reduces amyloid beta (Aβ) associated pathology in Alzheimer's disease (AD) mouse models. In the present study, oral administration of diosmin reduced cerebral Aβ oligomer levels, tau-hyperphosphorylation and cognitive impairment in the 3xTg-AD mouse model through glycogen synthase kinase-3 (GSK-3) and transient receptor potential canonical 6-related mechanisms. Diosmetin, one major bioactive metabolite of diosmin, increased inhibitory GSK-3β phosphorylation, while selectively reducing γ-secretase activity, Aβ generation, tau hyperphosphorylation and pro-inflammatory activation of microglia in vitro, without altering Notch processing. Therefore, both diosmin and diosmetin could be considered as potential candidates for novel anti-AD therapy.
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Affiliation(s)
- Darrell Sawmiller
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, FL, United States; James A. Haley Veteran's Administration Hospital, Tampa, FL, United States.
| | - Ahsan Habib
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Song Li
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, FL, United States; Center for Translational Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, China
| | - Donna Darlington
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Huayan Hou
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Jun Tian
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - R Douglas Shytle
- Center for Aging & Brain Repair, Department of Neurosurgery & Brain Repair, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Adam Smith
- Center for Aging & Brain Repair, Department of Neurosurgery & Brain Repair, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Brian Giunta
- Neuroimmunology Laboratory, Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Takashi Mori
- Departments of Biomedical Sciences and Pathology, Saitama Medical Center and Saitama Medical University, Kawagoe, Saitama, Japan
| | - Jun Tan
- Department of Psychiatry, Morsani College of Medicine, University of South Florida, Tampa, FL, United States; James A. Haley Veteran's Administration Hospital, Tampa, FL, United States.
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184
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Singh NA, Mandal AKA, Khan ZA. Potential neuroprotective properties of epigallocatechin-3-gallate (EGCG). Nutr J 2016; 15:60. [PMID: 27268025 PMCID: PMC4897892 DOI: 10.1186/s12937-016-0179-4] [Citation(s) in RCA: 159] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 06/02/2016] [Indexed: 12/17/2022] Open
Abstract
Neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD) enforce an overwhelming social and economic burden on society. They are primarily characterized through the accumulation of modified proteins, which further trigger biological responses such as inflammation, oxidative stress, excitotoxicity and modulation of signalling pathways. In a hope for cure, these diseases have been studied extensively over the last decade to successfully develop symptom-oriented therapies. However, so far no definite cure has been found. Therefore, there is a need to identify a class of drug capable of reversing neural damage and preventing further neural death. This review therefore assesses the reliability of the neuroprotective benefits of epigallocatechin-gallate (EGCG) by shedding light on their biological, pharmacological, antioxidant and metal chelation properties, with emphasis on their ability to invoke a range of cellular mechanisms in the brain. It also discusses the possible use of nanotechnology to enhance the neuroprotective benefits of EGCG.
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Affiliation(s)
- Neha Atulkumar Singh
- Department of Integrative Biology, School of Biosciences and Technology, VIT University, Vellore, 632014, Tamil Nadu, India
| | - Abul Kalam Azad Mandal
- Department of Biotechnology, School of Biosciences and Technology, VIT University, Vellore, 632014, Tamil Nadu, India
| | - Zaved Ahmed Khan
- Centre for Interdisciplinary Biomedical Research, Adesh University, Bathinda, Punjab, India.
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185
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Negatively charged hydrophobic nanoparticles inhibit amyloid β-protein fibrillation: The presence of an optimal charge density. REACT FUNCT POLYM 2016. [DOI: 10.1016/j.reactfunctpolym.2016.04.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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186
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Yang S, Liu W, Lu S, Tian YZ, Wang WY, Ling TJ, Liu RT. A Novel Multifunctional Compound Camellikaempferoside B Decreases Aβ Production, Interferes with Aβ Aggregation, and Prohibits Aβ-Mediated Neurotoxicity and Neuroinflammation. ACS Chem Neurosci 2016; 7:505-18. [PMID: 27015590 DOI: 10.1021/acschemneuro.6b00091] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Accumulating evidence suggested that soluble oligomeric β-amyloid protein (Aβ) exerts diverse roles in neuronal cell death, neuroinflammation, oxidative stress, and the eventual dementia associated with Alzheimer's disease (AD). Developing an agent with multiple properties may be a reasonable strategy for the treatment of AD. In this study, we isolated a novel multifunctional compound named camellikaempferoside B (YCF-2) from Fuzhuan brick tea. YCF-2 consists of kaempferol backbone, p-coumaric acid (p-CA) group, and a novel structure of rhamnopyranosyl group at the C-4' position, possessing the properties of both kaempferol and p-CA. YCF-2 significantly inhibited Aβ production by decreasing β-secretase activity. Moreover, YCF-2 suppressed Aβ42 fibrillation and facilitated nontoxic oligomer formation by binding to Aβ42 oligomers and by blocking the conformational transition to β-sheet. Furthermore, YCF-2 ameliorated Aβ-induced neuronal cell death, ROS production, inflammatory factor release, and microglia activation by blocking the NF-κB signaling pathway in microglia. These findings indicated that YCF-2 with a novel lead structure has potential applications for drug development for AD treatment.
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Affiliation(s)
- Shigao Yang
- National
Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Wen Liu
- National
Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
- School
of Life Science, Anhui Agricultural University, Hefei 230036, China
| | - Shuai Lu
- National
Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Yong-zhen Tian
- State
Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University 130 West Changjiang Rd., Hefei 230036, P. R. China
| | - Wei-yun Wang
- School
of Life Science, Anhui Agricultural University, Hefei 230036, China
| | - Tie-jun Ling
- State
Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University 130 West Changjiang Rd., Hefei 230036, P. R. China
| | - Rui-tian Liu
- National
Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
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187
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Neuroprotective Activity of (-)-Epigallocatechin Gallate against Lipopolysaccharide-Mediated Cytotoxicity. J Immunol Res 2016; 2016:4962351. [PMID: 27191001 PMCID: PMC4844887 DOI: 10.1155/2016/4962351] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/15/2016] [Accepted: 03/17/2016] [Indexed: 12/14/2022] Open
Abstract
Lipopolysaccharide- (LPS-) mediated systemic inflammation plays a critical role in neurodegenerative diseases. The present study was conducted to evaluate the protective effects of epigallocatechin gallate (EGCG), the major component in green tea, on LPS-mediated inflammation and neurotoxicity. LPS treatment of macrophages induced expression of proinflammatory cytokines (TNF-α, IL-1β, and IL-6). However, EGCG pretreatment of macrophages significantly inhibited LPS-mediated induction of these cytokines. In addition, EGCG significantly diminished LPS-induced inflammatory cytokines in the peripheral mononuclear blood cells (PBMCs). Supernatant from EGCG-pretreated and LPS-activated macrophage cultures was found to be less cytotoxic to neurons than that from non-EGCG-pretreated and LPS-activated macrophage cultures. Furthermore, EGCG treatment of neurons could inhibit LPS-induced production of reactive oxygen species (ROS). Thus EGCG represents a potent and useful neuroprotective agent for inflammation-mediated neurological disorders.
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188
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Ramachandran B, Jayavelu S, Murhekar K, Rajkumar T. Repeated dose studies with pure Epigallocatechin-3-gallate demonstrated dose and route dependant hepatotoxicity with associated dyslipidemia. Toxicol Rep 2016; 3:336-345. [PMID: 28959554 PMCID: PMC5615837 DOI: 10.1016/j.toxrep.2016.03.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 02/15/2016] [Accepted: 03/02/2016] [Indexed: 12/22/2022] Open
Abstract
EGCG (Epigallocatechin-3-gallate) is the major active principle catechin found in green tea. Skepticism regarding the safety of consuming EGCG is gaining attention, despite the fact that it is widely being touted for its potential health benefits, including anti-cancer properties. The lack of scientific data on safe dose levels of pure EGCG is of concern, while EGCG has been commonly studied as a component of GTE (Green tea extract) and not as a single active constituent. This study has been carried out to estimate the maximum tolerated non-toxic dose of pure EGCG and to identify the treatment related risk factors. In a fourteen day consecutive treatment, two different administration modalities were compared, offering an improved [i.p (intraperitoneal)] and limited [p.o (oral)] bioavailability. A trend of dose and route dependant hepatotoxicity was observed particularly with i.p treatment and EGCG increased serum lipid profile in parallel to hepatotoxicity. Fourteen day tolerable dose of EGCG was established as 21.1 mg/kg for i.p and 67.8 mg/kg for p.o. We also observed that, EGCG induced effects by both treatment routes are reversible, subsequent to an observation period for further fourteen days after cessation of treatment. It was demonstrated that the severity of EGCG induced toxicity appears to be a function of dose, route of administration and period of treatment.
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Affiliation(s)
- Balaji Ramachandran
- Department of Molecular Oncology, Cancer Institute (W.I.A), No. 38, Sardar Patel Road, Adyar, 600 036 Chennai, India
| | - Subramani Jayavelu
- Department of Molecular Oncology, Cancer Institute (W.I.A), No. 38, Sardar Patel Road, Adyar, 600 036 Chennai, India
| | - Kanchan Murhekar
- Department of Oncopathology, Cancer Institute (W.I.A), No. 38, Sardar Patel Road, Adyar, 600 036 Chennai, India
| | - Thangarajan Rajkumar
- Department of Molecular Oncology, Cancer Institute (W.I.A), No. 38, Sardar Patel Road, Adyar, 600 036 Chennai, India
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Chowdhury A, Sarkar J, Chakraborti T, Pramanik PK, Chakraborti S. Protective role of epigallocatechin-3-gallate in health and disease: A perspective. Biomed Pharmacother 2016; 78:50-59. [DOI: 10.1016/j.biopha.2015.12.013] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Revised: 12/03/2015] [Accepted: 12/15/2015] [Indexed: 12/28/2022] Open
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190
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Beyond the plasma cell: emerging therapies for immunoglobulin light chain amyloidosis. Blood 2016; 127:2275-80. [PMID: 26907632 DOI: 10.1182/blood-2015-11-681650] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 02/21/2016] [Indexed: 11/20/2022] Open
Abstract
Systemic immunoglobulin light chain (LC) amyloidosis (AL) is a potentially fatal disease caused by immunoglobulin LC produced by clonal plasma cells. These LC form both toxic oligomers and amyloid deposits disrupting vital organ function. Despite reduction of LC by chemotherapy, the restoration of organ function is highly variable and often incomplete. Organ damage remains the major source of mortality and morbidity in AL. This review focuses on the challenges posed by emerging therapies that may limit the toxicity of LC and improve organ function by accelerating the resorption of amyloid deposits.
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191
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Lin X, Bai G, Lin L, Wu H, Cai J, Ugen KE, Cao C. Vaccination induced changes in pro-inflammatory cytokine levels as an early putative biomarker for cognitive improvement in a transgenic mouse model for Alzheimer disease. Hum Vaccin Immunother 2016; 10:2024-31. [PMID: 25424812 DOI: 10.4161/hv.28735] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Several pieces of experimental evidence suggest that administration of anti-β amyloid (Aβ) vaccines, passive anti-Aβ antibodies or anti-inflammatory drugs can reduce Aβ deposition as well as associated cognitive/behavioral deficits in an Alzheimer disease (AD) transgenic (Tg) mouse model and, as such, may have some efficacy in human AD patients as well. In the investigation reported here an Aβ 1-42 peptide vaccine was administered to 16-month old APP+PS1 transgenic (Tg) mice in which Aβ deposition, cognitive memory deficits as well as levels of several pro-inflammatory cytokines were measured in response to the vaccination regimen. After vaccination, the anti-Aβ 1-42 antibody-producing mice demonstrated a significant reduction in the sera levels of 4 pro-inflammatory cytokines (TNF-α, IL-6, IL-1 α, and IL-12). Importantly, reductions in the cytokine levels of TNF-α and IL-6 were correlated with cognitive/behavioral improvement in the Tg mice. However, no differences in cerebral Aβ deposition in these mice were noted among the different control and experimental groups, i.e., Aβ 1-42 peptide vaccinated, control peptide vaccinated, or non-vaccinated mice. However, decreased levels of pro-inflammatory cytokines as well as improved cognitive performance were noted in mice vaccinated with the control peptide as well as those immunized with the Aβ 1-42 peptide. These findings suggest that reduction in pro-inflammatory cytokine levels in these mice may be utilized as an early biomarker for vaccination/treatment induced amelioration of cognitive deficits and are independent of Aβ deposition and, interestingly, antigen specific Aβ 1-42 vaccination. Since cytokine changes are typically related to T cell activation, the results imply that T cell regulation may have an important role in vaccination or other immunotherapeutic strategies in an AD mouse model and potentially in AD patients. Overall, these cytokine changes may serve as a predictive marker for AD development and progression as well as having potential therapeutic implications.
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Affiliation(s)
- Xiaoyang Lin
- a Department of Pharmacuetical Sciences College of Pharmacy; University of South Florida; Tampa, FL USA
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192
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Sy LK, Lok CN, Wang JY, Liu Y, Cheng L, Wan PK, Leung CT, Cao B, Kwong WL, Chang RCC, Che CM. Identification of "sarsasapogenin-aglyconed" timosaponins as novel Aβ-lowering modulators of amyloid precursor protein processing. Chem Sci 2016; 7:3206-3214. [PMID: 29997812 PMCID: PMC6005341 DOI: 10.1039/c5sc02377g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 12/28/2015] [Indexed: 11/21/2022] Open
Abstract
The “sarsasapogenin-aglyconed” timosaponins are Aβ lowering agents that may be useful for the development of Alzheimer’s disease therapeutics.
The inhibition of amyloid β (Aβ) peptide production is a key approach in the development of therapeutics for the treatment of Alzheimer's disease (AD). We have identified that timosaponins consisting of sarsasapogenin (SSG) as the aglycone can effectively lower the production of Aβ peptides and stimulate neurite outgrowth in neuronal cell cultures. Structure–activity relationship studies revealed that the cis-fused AB ring, 3β-configuration, spiroketal F-ring and 25S-configuration of SSG are the essential structural features responsible for the Aβ-lowering effects and neurite-stimulatory activity. New synthetic derivatives that retain the SSG scaffold also exhibited an Aβ lowering effect. Treatment of cells with timosaponins led to modulation of amyloid precursor protein (APP) processing through the suppression of β-cleavage and preferential lowering of the production of the 42-amino acid Aβ species (Aβ42) without affecting another γ-secretase substrate. The SSG and “SSG-aglyconed” timosaponins also penetrated brain tissue and lowered brain Aβ42 levels in mice. Our studies demonstrate that timosaponins represent a unique class of steroidal saponins that may be useful for the development of AD therapeutics.
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Affiliation(s)
- Lai-King Sy
- Department of Chemistry , The University of Hong Kong , Chemical Biology Centre , 8/F., The Hong Kong Jockey Club Building for Interdisciplinary Research, 5, Sassoon Road, Pokfulam , Hong Kong , China . ; ; Tel: +852-28592154
| | - Chun-Nam Lok
- Department of Chemistry , The University of Hong Kong , Chemical Biology Centre , 8/F., The Hong Kong Jockey Club Building for Interdisciplinary Research, 5, Sassoon Road, Pokfulam , Hong Kong , China . ; ; Tel: +852-28592154
| | - Juan-Yu Wang
- Department of Chemistry , The University of Hong Kong , Chemical Biology Centre , 8/F., The Hong Kong Jockey Club Building for Interdisciplinary Research, 5, Sassoon Road, Pokfulam , Hong Kong , China . ; ; Tel: +852-28592154
| | - Yungen Liu
- Department of Chemistry , The University of Hong Kong , Chemical Biology Centre , 8/F., The Hong Kong Jockey Club Building for Interdisciplinary Research, 5, Sassoon Road, Pokfulam , Hong Kong , China . ; ; Tel: +852-28592154
| | - Lu Cheng
- Department of Chemistry , The University of Hong Kong , Chemical Biology Centre , 8/F., The Hong Kong Jockey Club Building for Interdisciplinary Research, 5, Sassoon Road, Pokfulam , Hong Kong , China . ; ; Tel: +852-28592154
| | - Pui-Ki Wan
- Department of Chemistry , The University of Hong Kong , Chemical Biology Centre , 8/F., The Hong Kong Jockey Club Building for Interdisciplinary Research, 5, Sassoon Road, Pokfulam , Hong Kong , China . ; ; Tel: +852-28592154
| | - Chi-Ting Leung
- Department of Chemistry , The University of Hong Kong , Chemical Biology Centre , 8/F., The Hong Kong Jockey Club Building for Interdisciplinary Research, 5, Sassoon Road, Pokfulam , Hong Kong , China . ; ; Tel: +852-28592154
| | - Bei Cao
- Department of Chemistry , The University of Hong Kong , Chemical Biology Centre , 8/F., The Hong Kong Jockey Club Building for Interdisciplinary Research, 5, Sassoon Road, Pokfulam , Hong Kong , China . ; ; Tel: +852-28592154
| | - Wai-Lun Kwong
- Department of Chemistry , The University of Hong Kong , Chemical Biology Centre , 8/F., The Hong Kong Jockey Club Building for Interdisciplinary Research, 5, Sassoon Road, Pokfulam , Hong Kong , China . ; ; Tel: +852-28592154
| | - Raymond Chuen-Chung Chang
- Neurodegenerative Diseases Laboratory , School of Biomedical Sciences , LKS Faculty of Medicine , Research Centre of Heart, Brain and Hormone, and Healthy Aging , LKS Faculty of Medicine , State Key Laboratory of Brain and Cognitive Sciences , The University of Hong Kong , China
| | - Chi-Ming Che
- Department of Chemistry , The University of Hong Kong , Chemical Biology Centre , 8/F., The Hong Kong Jockey Club Building for Interdisciplinary Research, 5, Sassoon Road, Pokfulam , Hong Kong , China . ; ; Tel: +852-28592154
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193
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Zhang Q, Hu X, Wang W, Yuan Z. Study of a Bifunctional Aβ Aggregation Inhibitor with the Abilities of Antiamyloid-β and Copper Chelation. Biomacromolecules 2016; 17:661-8. [PMID: 26756252 DOI: 10.1021/acs.biomac.5b01603] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this study, a bifunctional Aβ aggregation inhibitor peptide, GGHRYYAAFFARR (GR), with the abilities to bind copper and antiamyloid was designed to inhibit the neurotoxicity of the Aβ-Cu(II) complex. The thioflavin T (ThT) assay, turbidimetric analysis, transmission electron microscopy (TEM), and (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay were used to study its potential inhibitory effect on Aβ aggregation. Our findings indicate that GGH was the specific chelating sequence and that the RYYAAFFARR (RR) component acted as an aggregation inhibitor. More importantly, GR significantly decreased the cytotoxicity of the Aβ-Cu(II) complex. The cell viability improved to 88%, which was higher than with the single functional peptide GGH and RR by 39% and 20%, respectively. Moreover, the qualitative effect of Cu(II) on the Aβ-Cu(II) complex was also studied. Our results indicate that Cu(II) induces the formation of the β-sheet structure with a subequimolar Cu(II):Aβ molar ratio (0.25:1) but led to increased ROS production at a supra-equimolar ratio.
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Affiliation(s)
- Qian Zhang
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, and ‡Collaborative Innovation Center of Chemical Science and Engineering, Nankai University , Tianjin 300071, China
| | - Xiaoyu Hu
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, and ‡Collaborative Innovation Center of Chemical Science and Engineering, Nankai University , Tianjin 300071, China
| | - Wei Wang
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, and ‡Collaborative Innovation Center of Chemical Science and Engineering, Nankai University , Tianjin 300071, China
| | - Zhi Yuan
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, and ‡Collaborative Innovation Center of Chemical Science and Engineering, Nankai University , Tianjin 300071, China
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194
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Almeida S, Alves MG, Sousa M, Oliveira PF, Silva BM. Are Polyphenols Strong Dietary Agents Against Neurotoxicity and Neurodegeneration? Neurotox Res 2016; 30:345-66. [PMID: 26745969 DOI: 10.1007/s12640-015-9590-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 12/10/2015] [Accepted: 12/12/2015] [Indexed: 12/21/2022]
Abstract
Life expectancy of most human populations has greatly increased as a result of factors including better hygiene, medical practice, and nutrition. Unfortunately, as humans age, they become more prone to suffer from neurodegenerative diseases and neurotoxicity. Polyphenols can be cheaply and easily obtained as part of a healthy diet. They present a wide range of biological activities, many of which have relevance for human health. Compelling evidence has shown that dietary phytochemicals, particularly polyphenols, have properties that may suppress neuroinflammation and prevent toxic and degenerative effects in the brain. The mechanisms by which polyphenols exert their action are not fully understood, but it is clear that they have a direct effect through their antioxidant activities. They have also been shown to modulate intracellular signaling cascades, including the PI3K-Akt, MAPK, Nrf2, and MEK pathways. Polyphenols also interact with a range of neurotransmitters, illustrating that these compounds can promote their health benefits in the brain through a direct, indirect, or complex action. We discuss whether polyphenols obtained from diet or food supplements are an effective strategy to prevent or treat neurodegeneration. We also discuss the safety, mechanisms of action, and the current and future relevance of polyphenols in clinical treatment of neurodegenerative diseases. As populations age, it is important to discuss the dietary strategies to avoid or counteract the effects of incurable neurodegenerative disorders, which already represent an enormous financial and emotional burden for health care systems, patients, and their families.
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Affiliation(s)
- Susana Almeida
- Department of Microscopy, Laboratory of Cell Biology and Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Marco G Alves
- CICS-UBI, Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Av. Infante D. Henrique, 6200-506, Covilhã, Portugal
| | - Mário Sousa
- Department of Microscopy, Laboratory of Cell Biology and Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal.,Centre for Reproductive Genetics Prof. Alberto Barros, Porto, Portugal
| | - Pedro F Oliveira
- Department of Microscopy, Laboratory of Cell Biology and Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal.,I3S - Institute of Health Research and Innovation, University of Porto, Porto, Portugal
| | - Branca M Silva
- CICS-UBI, Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Av. Infante D. Henrique, 6200-506, Covilhã, Portugal.
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195
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Nrf2–ARE pathway: An emerging target against oxidative stress and neuroinflammation in neurodegenerative diseases. Pharmacol Ther 2016; 157:84-104. [DOI: 10.1016/j.pharmthera.2015.11.003] [Citation(s) in RCA: 324] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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196
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Xu L, Tu S, Chen C, Zhao J, Zhang Y, Zhou P. Effect of EGCG On Fe(III)-induced conformational transition of silk fibroin, a model of protein related to neurodegenerative diseases. Biopolymers 2015; 105:100-107. [DOI: 10.1002/bip.22752] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Revised: 09/30/2015] [Accepted: 10/09/2015] [Indexed: 01/13/2023]
Affiliation(s)
- Lihui Xu
- Department of Macromolecular Science, State Key Laboratory of Molecular Engineering of Polymers; Fudan University; Shanghai 200433 China
| | - Sidong Tu
- Department of Macromolecular Science, State Key Laboratory of Molecular Engineering of Polymers; Fudan University; Shanghai 200433 China
| | - Congheng Chen
- Department of Macromolecular Science, State Key Laboratory of Molecular Engineering of Polymers; Fudan University; Shanghai 200433 China
| | - Juan Zhao
- Department of Macromolecular Science, State Key Laboratory of Molecular Engineering of Polymers; Fudan University; Shanghai 200433 China
| | - Yuan Zhang
- Department of Medicine; St Vincent's Hospital, the University of Melbourne; Fitzroy Victoria 3065 Australia
| | - Ping Zhou
- Department of Macromolecular Science, State Key Laboratory of Molecular Engineering of Polymers; Fudan University; Shanghai 200433 China
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197
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Bhat WF, Bhat SA, Bano B. Evaluation of polyphenols as possible therapeutics for amyloidoses: Comparative analysis of Kaempferol and Catechin. Int J Biol Macromol 2015; 81:60-8. [DOI: 10.1016/j.ijbiomac.2015.07.052] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Revised: 07/24/2015] [Accepted: 07/26/2015] [Indexed: 12/18/2022]
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198
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MacLeod R, Hillert EK, Cameron RT, Baillie GS. The role and therapeutic targeting of α-, β- and γ-secretase in Alzheimer's disease. Future Sci OA 2015; 1:FSO11. [PMID: 28031886 PMCID: PMC5137966 DOI: 10.4155/fso.15.9] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia in the elderly and its prevalence is set to increase rapidly in coming decades. However, there are as yet no available drugs that can halt or even stabilize disease progression. One of the main pathological features of AD is the presence in the brain of senile plaques mainly composed of aggregated β amyloid (Aβ), a derivative of the longer amyloid precursor protein (APP). The amyloid hypothesis proposes that the accumulation of Aβ within neural tissue is the initial event that triggers the disease. Here we review research efforts that have attempted to inhibit the generation of the Aβ peptide through modulation of the activity of the proteolytic secretases that act on APP and discuss whether this is a viable therapeutic strategy for treating AD.
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Affiliation(s)
- Ruth MacLeod
- Institute of Cardiovascular & Medical Sciences, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Ellin-Kristina Hillert
- Institute of Cardiovascular & Medical Sciences, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Ryan T Cameron
- Institute of Cardiovascular & Medical Sciences, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - George S Baillie
- Institute of Cardiovascular & Medical Sciences, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
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199
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Deng J, Habib A, Obregon DF, Barger SW, Giunta B, Wang YJ, Hou H, Sawmiller D, Tan J. Soluble amyloid precursor protein alpha inhibits tau phosphorylation through modulation of GSK3β signaling pathway. J Neurochem 2015; 135:630-7. [PMID: 26342176 PMCID: PMC4624213 DOI: 10.1111/jnc.13351] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 08/12/2015] [Accepted: 08/24/2015] [Indexed: 01/07/2023]
Abstract
We recently found that sAPPα decreases amyloid-beta generation by directly associating with β-site amyloid precursor protein (APP)-converting enzyme 1 (BACE1), thereby modulating APP processing. Because inhibition of BACE1 decreases glycogen synthase kinase 3 beta (GSK3β)-mediated Alzheimer's disease (AD)-like tau phosphorylation in AD patient-derived neurons, we determined whether sAPPα also reduces GSK3β-mediated tau phosphorylation. We initially found increased levels of inhibitory phosphorylation of GSK3β (Ser9) in primary neurons from sAPPα over-expressing mice. Further, recombinant human sAPPα evoked the same phenomenon in SH-SY5Y cells. Further, in SH-SY5Y cells over-expressing BACE1, and HeLa cells over-expressing human tau, sAPPα reduced GSK3β activity and tau phosphorylation. Importantly, the reductions in GSK3β activity and tau phosphorylation elicited by sAPPα were prevented by BACE1 but not γ-secretase inhibition. In accord, AD mice over-expressing human sAPPα had less GSK3β activity and tau phosphorylation compared with controls. These results implicate a direct relationship between APP β-processing and GSK3β-mediated tau phosphorylation and further define the central role of sAPPα in APP autoregulation and AD pathogenesis.
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Affiliation(s)
- Juan Deng
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry & Behavioral Neurosciences, Morsani College of Medicine; University of South Florida, Tampa, FL 33613
- Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Ahsan Habib
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry & Behavioral Neurosciences, Morsani College of Medicine; University of South Florida, Tampa, FL 33613
| | - Demian F. Obregon
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry & Behavioral Neurosciences, Morsani College of Medicine; University of South Florida, Tampa, FL 33613
| | - Steven W. Barger
- Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock, AR 72205
| | - Brian Giunta
- Neuroimmunology Laboratory, Department of Psychiatry & Behavioral Neurosciences, Morsani College of Medicine; University of South Florida, Tampa, FL 33613
| | - Yan-Jiang Wang
- Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Huayan Hou
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry & Behavioral Neurosciences, Morsani College of Medicine; University of South Florida, Tampa, FL 33613
| | - Darrell Sawmiller
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry & Behavioral Neurosciences, Morsani College of Medicine; University of South Florida, Tampa, FL 33613
| | - Jun Tan
- Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry & Behavioral Neurosciences, Morsani College of Medicine; University of South Florida, Tampa, FL 33613
- Address correspondence to: Dr. Jun Tan, Rashid Laboratory for Developmental Neurobiology, Silver Child Development Center, Department of Psychiatry & Behavioral Neurosciences, Morsani College of Medicine, University of South Florida, 3515 E Fletcher Ave. Tampa, FL 33613. Phone: 813-974-9326; Fax: 813-974-3223;
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200
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Venigalla M, Sonego S, Gyengesi E, Sharman MJ, Münch G. Novel promising therapeutics against chronic neuroinflammation and neurodegeneration in Alzheimer's disease. Neurochem Int 2015; 95:63-74. [PMID: 26529297 DOI: 10.1016/j.neuint.2015.10.011] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 10/23/2015] [Accepted: 10/24/2015] [Indexed: 12/22/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder, characterized by deposition of amyloid plaques and neurofibrillary tangles, as well as microglial and astroglial activation, and, finally, leading to neuronal dysfunction and death. Current treatments for AD primarily focus on enhancement of cholinergic transmission. However, these treatments are only symptomatic, and no disease-modifying drug is available for the treatment of AD patients. This review will provide an overview of the antioxidant, anti-inflammatory, anti-amyloidogenic, neuroprotective, and cognition-enhancing effects of a variety of nutraceuticals including curcumin, apigenin, docosahexaenoic acid, epigallocatechin gallate, α-lipoic acid and resveratrol and their potential for AD prevention and treatment. We suggest that therapeutic use of these compounds might lead to a safe strategy to delay the onset of AD or slow down its progression. The continuing investigation of the potential of these substances is necessary as they are promising compounds to yield a possible remedy for this pervasive disease.
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Affiliation(s)
- Madhuri Venigalla
- Dept of Pharmacology, School of Medicine, Western Sydney University, Campbelltown, NSW, Australia
| | - Sandra Sonego
- Dept of Pharmacology, School of Medicine, Western Sydney University, Campbelltown, NSW, Australia
| | - Erika Gyengesi
- Dept of Pharmacology, School of Medicine, Western Sydney University, Campbelltown, NSW, Australia; Molecular Medicine Research Group, Western Sydney University, Campbelltown, NSW, Australia
| | | | - Gerald Münch
- Dept of Pharmacology, School of Medicine, Western Sydney University, Campbelltown, NSW, Australia; National Institute of Complementary Medicine, Western Sydney University, Campbelltown, NSW, Australia; Molecular Medicine Research Group, Western Sydney University, Campbelltown, NSW, Australia.
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