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Qiang RR, Xiang Y, Zhang L, Bai XY, Zhang D, Li YJ, Yang YL, Liu XL. Ferroptosis: A new strategy for targeting Alzheimer's disease. Neurochem Int 2024; 178:105773. [PMID: 38789042 DOI: 10.1016/j.neuint.2024.105773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 05/09/2024] [Accepted: 05/21/2024] [Indexed: 05/26/2024]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a complex pathogenesis, which involves the formation of amyloid plaques and neurofibrillary tangles. Many recent studies have revealed a close association between ferroptosis and the pathogenesis of AD. Factors such as ferroptosis-associated iron overload, lipid peroxidation, disturbances in redox homeostasis, and accumulation of reactive oxygen species have been found to contribute to the pathological progression of AD. In this review, we explore the mechanisms underlying ferroptosis, describe the link between ferroptosis and AD, and examine the reported efficacy of ferroptosis inhibitors in treating AD. Finally, we discuss the potential challenges to ferroptosis inhibitors use in the clinic, enabling their faster use in clinical treatment.
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Affiliation(s)
| | - Yang Xiang
- College of Physical Education, Yan'an University, Shaanxi, 716000, China
| | - Lei Zhang
- School of Medicine, Yan'an University, Yan'an, China
| | - Xin Yue Bai
- School of Medicine, Yan'an University, Yan'an, China
| | - Die Zhang
- School of Medicine, Yan'an University, Yan'an, China
| | - Yang Jing Li
- School of Medicine, Yan'an University, Yan'an, China
| | - Yan Ling Yang
- School of Medicine, Yan'an University, Yan'an, China
| | - Xiao Long Liu
- School of Medicine, Yan'an University, Yan'an, China.
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Robertson KV, Rodriguez AS, Cartailler JP, Shrestha S, Schroeder KR, Valenti AM, Harrison FE, Hasty AH. Knockdown of microglial iron import gene, DMT1, worsens cognitive function and alters microglial transcriptional landscape in a sex-specific manner in the APP/PS1 model of Alzheimer's disease. RESEARCH SQUARE 2024:rs.3.rs-4559940. [PMID: 38978579 PMCID: PMC11230470 DOI: 10.21203/rs.3.rs-4559940/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Background Microglial cell iron load and inflammatory activation are significant hallmarks of late-stage Alzheimer's disease (AD). In vitro, microglia preferentially upregulate the iron importer, divalent metal transporter 1 (DMT1, gene name Slc11a2) in response to inflammatory stimuli, and excess iron can augment cellular inflammation, suggesting a feed-forward loop between iron import mechanisms and inflammatory signaling. However, it is not understood whether microglial iron import mechanisms directly contribute to inflammatory signaling and chronic disease in vivo. These studies determined the effects of microglial-specific knockdown of Slc11a2 on AD-related cognitive decline and microglial transcriptional phenotype. Methods In vitro experiments and RT-qPCR were used to assess a role for DMT1 in amyloid-β-associated inflammation. To determine the effects of microglial Slc11a2 knockdown on AD-related phenotypes in vivo, triple-transgenic Cx3cr1 Cre - ERT2 ;Slc11a2 flfl;APP/PS1 + or - mice were generated and administered corn oil or tamoxifen to induce knockdown at 5-6 months of age. Both sexes underwent behavioral analyses to assess cognition and memory (12-15 months of age). Hippocampal CD11b + microglia were magnetically isolated from female mice (15-17 months) and bulk RNA-sequencing analysis was conducted. Results DMT1 inhibition in vitro robustly decreased Aβ-induced inflammatory gene expression and cellular iron levels in conditions of excess iron. In vivo, Slc11a2 KD APP/PS1 female, but not male, mice displayed a significant worsening of memory function in Morris water maze and a fear conditioning assay, along with significant hyperactivity compared to control WT and APP/PS1 mice. Hippocampal microglia from Slc11a2 KD APP/PS1 females displayed significant increases in Enpp2, Ttr, and the iron-export gene, Slc40a1, compared to control APP/PS1 cells. Slc11a2 KD cells from APP/PS1 females also exhibited decreased expression of markers associated with disease-associated microglia (DAMs), such as Apoe, Ctsb, Csf1, and Hif1α. Conclusions This work suggests a sex-specific role for microglial iron import gene Slc11a2 in propagating behavioral and cognitive phenotypes in the APP/PS1 model of AD. These data also highlight an association between loss of a DAM-like phenotype in microglia and cognitive deficits in Slc11a2 KD APP/PS1 female mice. Overall, this work illuminates an iron-related pathway in microglia that may serve a protective role during disease and offers insight into mechanisms behind disease-related sex differences.
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Chavoshinezhad S, Beirami E, Izadpanah E, Feligioni M, Hassanzadeh K. Molecular mechanism and potential therapeutic targets of necroptosis and ferroptosis in Alzheimer's disease. Biomed Pharmacother 2023; 168:115656. [PMID: 37844354 DOI: 10.1016/j.biopha.2023.115656] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 10/01/2023] [Accepted: 10/04/2023] [Indexed: 10/18/2023] Open
Abstract
Alzheimer's disease (AD), a neurodegenerative condition, is defined by neurofibrillary tangles, amyloid plaques, and gradual cognitive decline. Regardless of the advances in understanding AD's pathogenesis and progression, its causes are still contested, and there are currently no efficient therapies for the illness. The post-mortem analyses revealed widespread neuronal loss in multiple brain regions in AD, evidenced by a decrease in neuronal density and correlated with the disease's progression and cognitive deterioration. AD's neurodegeneration is complicated, and different types of neuronal cell death, alone or in combination, play crucial roles in this process. Recently, the involvement of non-apoptotic programmed cell death in the neurodegenerative mechanisms of AD has received a lot of attention. Aberrant activation of necroptosis and ferroptosis, two newly discovered forms of regulated non-apoptotic cell death, is thought to contribute to neuronal cell death in AD. In this review, we first address the main features of necroptosis and ferroptosis, cellular signaling cascades, and the mechanisms involved in AD pathology. Then, we discuss the latest therapies targeting necroptosis and ferroptosis in AD animal/cell models and human research to provide vital information for AD treatment.
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Affiliation(s)
- Sara Chavoshinezhad
- Cellular and Molecular Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran.
| | - Elmira Beirami
- Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Esmael Izadpanah
- Cellular and Molecular Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | - Marco Feligioni
- Laboratory of Neuronal Cell Signaling, EBRI Rita Levi-Montalcini Foundation, 00161 Rome, Italy; Department of Neurorehabilitation Sciences, Casa di Cura del Policlinico, 20144 Milan, Italy.
| | - Kambiz Hassanzadeh
- Robert Wood Johnson Medical School Institute for Neurological Therapeutics, and Department of Neurology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
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Luo J, Collingwood JF. Effective R 2 relaxation rate, derived from dual-contrast fast-spin-echo MRI, enables detection of hemisphere differences in iron level and dopamine function in Parkinson's disease and healthy individuals. J Neurosci Methods 2022; 382:109708. [PMID: 36089168 DOI: 10.1016/j.jneumeth.2022.109708] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 08/26/2022] [Accepted: 09/06/2022] [Indexed: 01/05/2023]
Abstract
BACKGROUND Clinical estimates of brain iron concentration are achievable with quantitative transverse relaxation rate R2, via time-consuming multiple spin-echo (SE) sequences. The objective of this study was to investigate whether quantitative iron-sensitive information may be derived from 3.0 T dual-contrast fast-spin-echo (FSE) sequences (typically employed in anatomical non-quantitative evaluations), as a routinely-collected alternative to evaluate iron levels in healthy (HC) and Parkinson's disease (PD) brains. NEW METHOD MRI 3.0 T FSE data from the Parkinson's Progression Markers Initiative (PPMI) (12 PD, 12 age- and gender-matched HC subjects) were cross-sectionally and longitudinally evaluated. A new measure, 'effective R2', was calculated for bilateral subcortical grey matter (caudate nucleus, putamen, globus pallidus, red nucleus, substantia nigra). Linear regression analysis was performed to correlate 'effective R2' with models of age-dependent brain iron concentration and striatal dopamine transporter (DaT) receptor binding ratio. RESULTS Effective R2 was strongly correlated with estimated brain iron concentration. In PD, putaminal effective R2 difference was observed between the hemispheres contra-/ipsi-lateral to the predominantly symptomatic side at onset. This hemispheric difference was correlated with the putaminal DaT binding ratios in PD. COMPARISON WITH EXISTING METHOD(S) Effective R2, derived from rapid dual-contrast FSE sequences, showed viability as an alternative to R2 from SE sequences. Linear correlation of effective R2 with estimated iron concentration was comparable to documented iron-dependent R2. The effective R2 correlation coefficient was consistent with theoretical R2 iron-dependence at 3.0 T. CONCLUSIONS Effective R2 has clinical potential as a fast quantitative method, as an alternative to R2, to aid evaluation of brain iron levels and DaT function.
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Affiliation(s)
- Jierong Luo
- School of Engineering, University of Warwick, Coventry CV4 7AL, United Kingdom
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Nakhid D, McMorris C, Sun H, Gibbard WB, Tortorelli C, Lebel C. Brain volume and magnetic susceptibility differences in children and adolescents with prenatal alcohol exposure. Alcohol Clin Exp Res 2022; 46:1797-1807. [PMID: 36016464 DOI: 10.1111/acer.14928] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 08/09/2022] [Accepted: 08/18/2022] [Indexed: 02/01/2023]
Abstract
BACKGROUND Prenatal alcohol exposure (PAE) can negatively affect brain development thereby increasing the risk of cognitive deficits, behavioral challenges, and mental health problems. Brain iron is important for a number of physiological processes for healthy brain development. Animal studies show that PAE reduced brain iron; however, this has not been investigated in human children with PAE. METHODS We studied 20 children and adolescents with PAE and 44 unexposed children and adolescents aged 7.5 to 15 years. All children underwent quantitative susceptibility mapping and T1-weighted magnetic resonance imaging scans. Susceptibility and volume measurements of the caudate, putamen, pallidum, thalamus, amygdala, hippocampus, and nucleus accumbens were extracted using FreeSurfer. ANCOVAs were used to compare volume and susceptibility between groups for each region of interest, controlling for age and gender. For structures where susceptibility differed by group, we also tested for an association between intelligence quotient (IQ) and susceptibility. RESULTS There were no significant group differences in susceptibility after multiple comparison correction, though the PAE group had higher susceptibility in the thalamus compared to unexposed participants before correction (p = 0.032, q = 0.230). There was no association between IQ and thalamus susceptibility. The PAE group had significantly lower volume in the bilateral caudate, bilateral pallidum, and left putamen. CONCLUSIONS These findings suggest susceptibility may be altered in children and adolescents with PAE, though more research is needed. Volume reductions are consistent with previous literature and likely underlie cognitive and behavioral deficits associated with PAE.
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Affiliation(s)
- Daphne Nakhid
- Department of Neuroscience, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute (ACHRI), University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Carly McMorris
- Alberta Children's Hospital Research Institute (ACHRI), University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,School and Applied Child Psychology, Werklund School of Education, University of Calgary, Calgary, Alberta, Canada.,Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada
| | - Hongfu Sun
- School of Information Technology and Electrical Engineering, University of Queensland, Brisbane, Queensland, Australia
| | - William Benton Gibbard
- Alberta Children's Hospital Research Institute (ACHRI), University of Calgary, Calgary, Alberta, Canada.,Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada
| | - Christina Tortorelli
- Department of Child Studies and Social Work, Mount Royal University, Calgary, Alberta, Canada
| | - Catherine Lebel
- Alberta Children's Hospital Research Institute (ACHRI), University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Department of Radiology, University of Calgary, Calgary, Alberta, Canada
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Rao IY, Hanson LR, Johnson JC, Rosenbloom MH, Frey WH. Brain Glucose Hypometabolism and Iron Accumulation in Different Brain Regions in Alzheimer's and Parkinson's Diseases. Pharmaceuticals (Basel) 2022; 15:551. [PMID: 35631378 PMCID: PMC9143620 DOI: 10.3390/ph15050551] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/17/2022] [Accepted: 04/27/2022] [Indexed: 02/01/2023] Open
Abstract
The aim of this study was to examine the relationship between the presence of glucose hypometabolism (GHM) and brain iron accumulation (BIA), two potential pathological mechanisms in neurodegenerative disease, in different regions of the brain in people with late-onset Alzheimer's disease (AD) or Parkinson's disease (PD). Studies that conducted fluorodeoxyglucose positron emission tomography (FDG-PET) to map GHM or quantitative susceptibility mapping-magnetic resonance imaging (QSM-MRI) to map BIA in the brains of patients with AD or PD were reviewed. Regions of the brain where GHM or BIA were reported in each disease were compared. In AD, both GHM and BIA were reported in the hippocampus, temporal, and parietal lobes. GHM alone was reported in the cingulate gyrus, precuneus and occipital lobe. BIA alone was reported in the caudate nucleus, putamen and globus pallidus. In PD, both GHM and BIA were reported in thalamus, globus pallidus, putamen, hippocampus, and temporal and frontal lobes. GHM alone was reported in cingulate gyrus, caudate nucleus, cerebellum, and parietal and occipital lobes. BIA alone was reported in the substantia nigra and red nucleus. GHM and BIA are observed independent of one another in various brain regions in both AD and PD. This suggests that GHM is not always necessary or sufficient to cause BIA and vice versa. Hypothesis-driven FDG-PET and QSM-MRI imaging studies, where both are conducted on individuals with AD or PD, are needed to confirm or disprove the observations presented here about the potential relationship or lack thereof between GHM and BIA in AD and PD.
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Affiliation(s)
- Indira Y. Rao
- HealthPartners Center for Memory and Aging, 295 Phalen Boulevard, St. Paul, MN 55130, USA; (I.Y.R.); (L.R.H.); (M.H.R.)
| | - Leah R. Hanson
- HealthPartners Center for Memory and Aging, 295 Phalen Boulevard, St. Paul, MN 55130, USA; (I.Y.R.); (L.R.H.); (M.H.R.)
- HealthPartners Institute, Bloomington, MN 55425, USA
| | - Julia C. Johnson
- HealthPartners Struthers Parkinson’s Center, Minneapolis, MN 55427, USA;
| | - Michael H. Rosenbloom
- HealthPartners Center for Memory and Aging, 295 Phalen Boulevard, St. Paul, MN 55130, USA; (I.Y.R.); (L.R.H.); (M.H.R.)
| | - William H. Frey
- HealthPartners Center for Memory and Aging, 295 Phalen Boulevard, St. Paul, MN 55130, USA; (I.Y.R.); (L.R.H.); (M.H.R.)
- HealthPartners Institute, Bloomington, MN 55425, USA
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Kim JH, Lim DK, Suh YH, Chang KA. Long-Term Treatment of Cuban Policosanol Attenuates Abnormal Oxidative Stress and Inflammatory Response via Amyloid Plaques Reduction in 5xFAD Mice. Antioxidants (Basel) 2021; 10:antiox10081321. [PMID: 34439569 PMCID: PMC8389325 DOI: 10.3390/antiox10081321] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/17/2021] [Accepted: 08/18/2021] [Indexed: 12/27/2022] Open
Abstract
Alzheimer’s disease (AD) is a progressive neurodegenerative disorder resulting in cognitive decline or dementia, the number of patients with AD is continuously increasing. Although a lot of great progress has been made in research and development of AD therapeutics, there is no fundamental cure for this disease yet. This study demonstrated the memory-improving effects of Cuban policosanol (PCO) in 5xFAD mice, which is an animal model of AD. Following 4-months of treatment with PCO in 5xFAD mice, we found that the number of amyloid plaques decreased in the brain compared to the vehicle-treated 5xFAD mice. Long-term PCO treatment in 5xFAD mice resulted in the reduction of gliosis and abnormal inflammatory cytokines level (interleukin [IL]-1β, IL-6, and tumor necrosis factor [TNF]-α) in the cortex and hippocampus. Levels of lipid peroxide (4-hydroxynonenal [4-HNE]) and superoxide dismutase (SOD1 and SOD2) levels were also recoverd in the brains of PCO-treated 5xFAD mice. Notably, PCO administration reduced memory deficits in the passive avoidance test, as well as synaptic loss (PSD-95, synaptophysin) in 5xFAD mice. Collectively, we identified the potential effects of PCO as a useful supplement to delay or prevent AD progression by inhibiting the formation of Aβ plaques in the brain.
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Affiliation(s)
- Jin-Ho Kim
- Department of Health Sciences and Technology, Gachon Advanced Insiue for Healh Sciences & Technology (GAIHST), Gachon University, Incheon 21999, Korea;
| | - Dong-Kyun Lim
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (D.-K.L.); (Y.-H.S.)
| | - Yoo-Hun Suh
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (D.-K.L.); (Y.-H.S.)
- Department of Pharmacology, College of Medicine, Seoul National University, Seoul 03080, Korea
| | - Keun-A Chang
- Department of Health Sciences and Technology, Gachon Advanced Insiue for Healh Sciences & Technology (GAIHST), Gachon University, Incheon 21999, Korea;
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (D.-K.L.); (Y.-H.S.)
- Department of Pharmacology, College of Medicine, Gachon University, Incheon 21999, Korea
- Correspondence: ; Tel.: +82-32-899-6411
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Vittori DC, Chamorro ME, Hernández YV, Maltaneri RE, Nesse AB. Erythropoietin and derivatives: Potential beneficial effects on the brain. J Neurochem 2021; 158:1032-1057. [PMID: 34278579 DOI: 10.1111/jnc.15475] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 06/24/2021] [Accepted: 07/14/2021] [Indexed: 12/16/2022]
Abstract
Erythropoietin (Epo), the main erythropoiesis-stimulating factor widely prescribed to overcome anemia, is also known nowadays for its cytoprotective action on non-hematopoietic tissues. In this context, Epo showed not only its ability to cross the blood-brain barrier, but also its expression in the brain of mammals. In clinical trials, recombinant Epo treatment has been shown to stimulate neurogenesis; improve cognition; and activate antiapoptotic, antioxidant, and anti-inflammatory signaling pathways. These mechanisms, proposed to characterize a neuroprotective property, opened new perspectives on the Epo pharmacological potencies. However, many questions arise about a possible physiological role of Epo in the central nervous system (CNS) and the factors or environmental conditions that induce its expression. Although Epo may be considered a strong candidate to be used against neuronal damage, long-term treatments, particularly when high Epo doses are needed, may induce thromboembolic complications associated with increases in hematocrit and blood viscosity. To avoid these adverse effects, different Epo analogs without erythropoietic activity but maintaining neuroprotection ability are currently being investigated. Carbamylated erythropoietin, as well as alternative molecules like Epo fusion proteins and partial peptides of Epo, seems to match this profile. This review will focus on the discussion of experimental evidence reported in recent years linking erythropoietin and CNS function through investigations aimed at finding benefits in the treatment of neurodegenerative diseases. In addition, it will review the proposed mechanisms for novel derivatives which may clarify and, eventually, improve the neuroprotective action of Epo.
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Affiliation(s)
- Daniela C Vittori
- Department of Biological Chemistry, National Scientific and Technical Research Council, Institute of Biological Chemistry (IQUIBICEN), School of Exact and Natural Sciences, University of Buenos Aires, Buenos Aires, Argentina
| | - María E Chamorro
- Department of Biological Chemistry, National Scientific and Technical Research Council, Institute of Biological Chemistry (IQUIBICEN), School of Exact and Natural Sciences, University of Buenos Aires, Buenos Aires, Argentina
| | - Yender V Hernández
- Department of Biological Chemistry, National Scientific and Technical Research Council, Institute of Biological Chemistry (IQUIBICEN), School of Exact and Natural Sciences, University of Buenos Aires, Buenos Aires, Argentina
| | - Romina E Maltaneri
- Department of Biological Chemistry, National Scientific and Technical Research Council, Institute of Biological Chemistry (IQUIBICEN), School of Exact and Natural Sciences, University of Buenos Aires, Buenos Aires, Argentina
| | - Alcira B Nesse
- Department of Biological Chemistry, National Scientific and Technical Research Council, Institute of Biological Chemistry (IQUIBICEN), School of Exact and Natural Sciences, University of Buenos Aires, Buenos Aires, Argentina
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Spence H, McNeil CJ, Waiter GD. The impact of brain iron accumulation on cognition: A systematic review. PLoS One 2020; 15:e0240697. [PMID: 33057378 PMCID: PMC7561208 DOI: 10.1371/journal.pone.0240697] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 10/01/2020] [Indexed: 12/31/2022] Open
Abstract
Iron is involved in many processes in the brain including, myelin generation, mitochondrial function, synthesis of ATP and DNA and the cycling of neurotransmitters. Disruption of normal iron homeostasis can result in iron accumulation in the brain, which in turn can partake in interactions which amplify oxidative damage. The development of MRI techniques for quantifying brain iron has allowed for the characterisation of the impact that brain iron has on cognition and neurodegeneration. This review uses a systematic approach to collate and evaluate the current literature which explores the relationship between brain iron and cognition. The following databases were searched in keeping with a predetermined inclusion criterion: Embase Ovid, PubMed and PsychInfo (from inception to 31st March 2020). The included studies were assessed for study characteristics and quality and their results were extracted and summarised. This review identified 41 human studies of varying design, which statistically assessed the relationship between brain iron and cognition. The most consistently reported interactions were in the Caudate nuclei, where increasing iron correlated poorer memory and general cognitive performance in adulthood. There were also consistent reports of a correlation between increased Hippocampal and Thalamic iron and poorer memory performance, as well as, between iron in the Putamen and Globus Pallidus and general cognition. We conclude that there is consistent evidence that brain iron is detrimental to cognitive health, however, more longitudinal studies will be required to fully understand this relationship and to determine whether iron occurs as a primary cause or secondary effect of cognitive decline.
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Affiliation(s)
- Holly Spence
- Aberdeen Biomedical Imaging Centre, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Chris J. McNeil
- Aberdeen Biomedical Imaging Centre, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Gordon D. Waiter
- Aberdeen Biomedical Imaging Centre, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
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Wearn AR, Nurdal V, Saunders-Jennings E, Knight MJ, Isotalus HK, Dillon S, Tsivos D, Kauppinen RA, Coulthard EJ. T2 heterogeneity: a novel marker of microstructural integrity associated with cognitive decline in people with mild cognitive impairment. Alzheimers Res Ther 2020; 12:105. [PMID: 32912337 PMCID: PMC7488446 DOI: 10.1186/s13195-020-00672-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 08/25/2020] [Indexed: 02/08/2023]
Abstract
BACKGROUND Early Alzheimer's disease (AD) diagnosis is vital for development of disease-modifying therapies. Prior to significant brain tissue atrophy, several microstructural changes take place as a result of Alzheimer's pathology. These include deposition of amyloid, tau and iron, as well as altered water homeostasis in tissue and some cell death. T2 relaxation time, a quantitative MRI measure, is sensitive to these changes and may be a useful non-invasive, early marker of tissue integrity which could predict conversion to dementia. We propose that different microstructural changes affect T2 in opposing ways, such that average 'midpoint' measures of T2 are less sensitive than measuring distribution width (heterogeneity). T2 heterogeneity in the brain may present a sensitive early marker of AD pathology. METHODS In this cohort study, we tested 97 healthy older controls, 49 people with mild cognitive impairment (MCI) and 10 with a clinical diagnosis of AD. All participants underwent structural MRI including a multi-echo sequence for quantitative T2 assessment. Cognitive change over 1 year was assessed in 20 participants with MCI. T2 distributions were modelled in the hippocampus and thalamus using log-logistic distribution giving measures of log-median value (midpoint; T2μ) and distribution width (heterogeneity; T2σ). RESULTS We show an increase in T2 heterogeneity (T2σ; p < .0001) in MCI compared to healthy controls, which was not seen with midpoint (T2μ; p = .149) in the hippocampus and thalamus. Hippocampal T2 heterogeneity predicted cognitive decline over 1 year in MCI participants (p = .018), but midpoint (p = .132) and volume (p = .315) did not. Age affects T2, but the effects described here are significant even after correcting for age. CONCLUSIONS We show that T2 heterogeneity can identify subtle changes in microstructural integrity of brain tissue in MCI and predict cognitive decline over a year. We describe a new model that considers the competing effects of factors that both increase and decrease T2. These two opposing forces suggest that previous conclusions based on T2 midpoint may have obscured the true potential of T2 as a marker of subtle neuropathology. We propose that T2 heterogeneity reflects microstructural integrity with potential to be a widely used early biomarker of conditions such as AD.
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Affiliation(s)
- Alfie R Wearn
- Bristol Medical School, University of Bristol, Bristol, UK.
- Institute of Clinical Neurosciences, North Bristol NHS Trust, Bristol, UK.
| | - Volkan Nurdal
- Bristol Medical School, University of Bristol, Bristol, UK
| | | | - Michael J Knight
- School of Psychological Science, University of Bristol, Bristol, UK
| | | | - Serena Dillon
- Bristol Medical School, University of Bristol, Bristol, UK
| | - Demitra Tsivos
- Bristol Medical School, University of Bristol, Bristol, UK
| | | | - Elizabeth J Coulthard
- Bristol Medical School, University of Bristol, Bristol, UK
- Institute of Clinical Neurosciences, North Bristol NHS Trust, Bristol, UK
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Damulina A, Pirpamer L, Soellradl M, Sackl M, Tinauer C, Hofer E, Enzinger C, Gesierich B, Duering M, Ropele S, Schmidt R, Langkammer C. Cross-sectional and Longitudinal Assessment of Brain Iron Level in Alzheimer Disease Using 3-T MRI. Radiology 2020; 296:619-626. [PMID: 32602825 DOI: 10.1148/radiol.2020192541] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Background Deep gray matter structures in patients with Alzheimer disease (AD) contain higher brain iron concentrations. However, few studies have included neocortical areas, which are challenging to assess with MRI. Purpose To investigate baseline and change in brain iron levels using MRI at 3 T with R2* relaxation rate mapping in individuals with AD compared with healthy control (HC) participants. Materials and Methods In this prospective study, participants with AD recruited between 2010 and 2016 and age-matched HC participants selected from 2010 to 2014 were evaluated. Of 100 participants with AD, 56 underwent subsequent neuropsychological testing and brain MRI at a mean follow-up of 17 months. All participants underwent 3-T MRI, including R2* mapping corrected for macroscopic B0 field inhomogeneities. Anatomic structures were segmented, and median R2* values were calculated in the neocortex and cortical lobes, basal ganglia (BG), hippocampi, and thalami. Multivariable linear regression analysis was applied to study the difference in R2* levels between groups and the association between longitudinal changes in R2* values and cognition in the AD group. Results A total of 100 participants with AD (mean age, 73 years ± 9 [standard deviation]; 58 women) and 100 age-matched HC participants (mean age, 73 years ± 9; 60 women) were evaluated. Median R2* levels were higher in the AD group than in the HC group in the BG (HC, 29.0 sec-1; AD, 30.2 sec-1; P = .01) and total neocortex (HC, 17.0 sec-1; AD, 17.4 sec-1; P < .001) and regionally in the occipital (HC, 19.6 sec-1; AD, 20.2 sec-1; P = .007) and temporal (HC, 16.4 sec-1; AD, 18.1 sec-1; P < .001) lobes. R2* values in the temporal lobe were associated with longitudinal changes in Consortium to Establish a Registry for Alzheimer's Disease total score (β = -3.23 score/sec-1, P = .003) in participants with AD independent of longitudinal changes in brain volume. Conclusion Iron concentration in the deep gray matter and neocortical regions was higher in patients with Alzheimer disease than in healthy control participants. Change in iron levels over time in the temporal lobe was associated with cognitive decline in individuals with Alzheimer disease. © RSNA, 2020 Online supplemental material is available for this article.
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Affiliation(s)
- Anna Damulina
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Lukas Pirpamer
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Martin Soellradl
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Maximilian Sackl
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Christian Tinauer
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Edith Hofer
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Christian Enzinger
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Benno Gesierich
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Marco Duering
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Stefan Ropele
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Reinhold Schmidt
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
| | - Christian Langkammer
- From the Department of Neurology (A.D., L.P., M. Soellradl, M. Sackl, C.T., E.H., C.E., S.R., R.S., C.L.), Institute for Medical Informatics, Statistics and Documentation (E.H.), and Division of Neuroradiology, Vascular, and Interventional Radiology, Department of Radiology (C.E.), Medical University of Graz, Graz, Auenbruggerplatz 22, 8036 Graz, Austria; and Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany (B.G., M.D.)
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Quantitative susceptibility mapping in β-Amyloid PET-stratified patients with dementia and healthy controls - A hybrid PET/MRI study. Eur J Radiol 2020; 131:109243. [PMID: 32916411 DOI: 10.1016/j.ejrad.2020.109243] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 07/23/2020] [Accepted: 08/11/2020] [Indexed: 11/21/2022]
Abstract
PURPOSE Post-mortem and in-vivo MRI data suggest an accumulation of iron in the brain of Alzheimer's disease (AD) patients. The majority of studies in clinically diagnosed AD patients found an increase of iron-sensitive MRI signals in the putamen. As the clinical diagnosis shows only a moderate sensitivity, Aβ-PET was used to further stratify patients with the clinical diagnosis of AD. Aim of this exploratory study was to examine whether Aβ-positive (AD) and Aβ-negative (non-AD) patients differ in their regional magnetic susceptibility compared to healthy controls (HCs) and whether regional susceptibility values correlate with mini mental state examination (MMSE) scores or global Aβ-load. METHODS We retrospectively analyzed [11C]PiB PET/MRI data of 11 HCs, 16 AD and 10 non-AD patients. We used quantitative susceptibility mapping (QSM) as iron-sensitive MRI signal measured at the 3 T PET/MR scanner. Global cerebral Aβ-load was determined by composite [11C]PiB SUV ratios. RESULTS Compared to HCs, AD patients showed higher QSM values in putamen (0.049 ± 0.033 vs. 0.002 ± 0.031; p = 0.006), while non-AD patients showed lower QSM values in caudate nucleus (0.003 ± 0.027 vs. 0.051 ± 0.039; p = 0.006). There was a trend towards a significant correlation between putaminal QSM and MMSE values (ρ=-0.340, p = 0.053). In AD patients, global Aβ-load and putaminal QSM values were significantly correlated (ρ=-0.574, p = 0.020). CONCLUSIONS These data indicate that AD and non-AD patients may show different cerebral iron pathologies which might be detectable by QSM MRI, and might be linked to neurodegeneration. Overall, the data encourage further investigations in well-defined patient cohorts to clarify the value of QSM/magnetic susceptibility in the course of neurodegenerative diseases and its potential as diagnostic biomarker.
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13
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Dorsal hippocampal changes in T2 relaxation times are associated with early spatial cognitive deficits in 5XFAD mice. Brain Res Bull 2019; 153:150-161. [PMID: 31422072 DOI: 10.1016/j.brainresbull.2019.08.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 08/12/2019] [Accepted: 08/13/2019] [Indexed: 01/01/2023]
Abstract
T2 relaxation time (T2) alterations may serve as markers for early detection and disease progression monitoring by reflecting brain microstructural integrity in Alzheimer's disease (AD). However, the characteristics of T2 alterations during the early stage of AD remain elusive. We explored T2 alterations and their possible correlations with cognitive function in 5XFAD mice at early ages (1, 2, 3, and 5 months of age). Voxel-based analysis (VBA) and region of interest (ROI) analysis showed a decreased T2 in the hippocampus of 2-, 3-, and 5-month-old 5XFAD mice compared to those of controls. The dorsal hippocampal T2 decreased earlier than the ventral hippocampus T2. A significant correlation was observed between Morris water maze (MWM) test cognitive behavior and the dorsal hippocampus T2 in 5XFAD mice. These results indicated that the microstructural integrity of brain tissues, particularly the hippocampus, was impaired early and the impairment became more extensive and severe during disease progression. Furthermore, the dorsal hippocampus is a crucial component involved in spatial cognition impairment in young 5XFAD mice.
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14
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Tiepolt S, Schäfer A, Rullmann M, Roggenhofer E, Gertz HJ, Schroeter ML, Patt M, Bazin PL, Jochimsen TH, Turner R, Sabri O, Barthel H. Quantitative Susceptibility Mapping of Amyloid-β Aggregates in Alzheimer's Disease with 7T MR. J Alzheimers Dis 2019; 64:393-404. [PMID: 29865069 DOI: 10.3233/jad-180118] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND PET imaging is an established technique to detect cerebral amyloid-β (Aβ) plaques in vivo. Some preclinical and postmortem data report an accumulation of redox-active iron near Aβ plaques. Quantitative susceptibility mapping (QSM) at high-field MRI enables iron deposits to be depicted with high spatial resolution. OBJECTIVE Aim of this study was to examine whether iron and Aβ plaque accumulation is related and thus, whether 7T MRI might be an additive diagnostic tool to Aβ PET imaging. METHODS Postmortem human Alzheimer's disease (AD) and healthy control (HC) frontal gray matter (GM) was imaged with 7T MRI which resulted in T1 maps and QSM. Aβ plaque load was determined by histopathology. In vivo, 10 Aβ PET-positive AD patients (74.1±6.0a) and 10 Aβ PET-negative HCs (67.1±4.4a) underwent 7T MR examination and QSM maps were analyzed. Severity of cognitive deficits was determined by MMSE. RESULTS Postmortem, the susceptibility of Aβ plaque-containing GM were higher than those of Aβ plaque-free GM (0.011±0.002 versus - 0.008±0.003 ppm, p < 0.001). In vivo, only the bilateral globus pallidus showed significantly higher susceptibility in AD patients compared to HCs (right: 0.277±0.018 versus - 0.009±0.009 ppm; left: 0.293±0.014 versus - 0.007±0.012 ppm, p < 0.0001). The pallidal QSM values were negatively correlated with those of the MMSE (r = - 0.69, p = 0.001). CONCLUSION The postmortem study revealed significant susceptibility differences between the Aβ plaque-containing and Aβ plaque-free GM, whereas in vivo only the QSM values of the globus pallidus differed significantly between AD and HC group. The pallidal QSM values correlated with the severity of cognitive deficits. These findings encourage efforts to optimize the 7T-QSM methodology.
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Affiliation(s)
- Solveig Tiepolt
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany
| | - Andreas Schäfer
- Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Siemens Healthcare GmbH, Diagnostic Imaging, Magnetic Resonance, Research & Development, Erlangen, Germany
| | - Michael Rullmann
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany.,Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Elisabeth Roggenhofer
- Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,LREN, Department for Clinical Neurosciences, CHUV, University of Lausanne, Lausanne, Switzerland
| | | | | | - Matthias L Schroeter
- Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Clinic for Cognitive Neurology, University Leipzig, Germany
| | - Marianne Patt
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany
| | - Pierre-Louis Bazin
- Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Thies H Jochimsen
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany
| | - Robert Turner
- Max-Planck-Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Osama Sabri
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany
| | - Henryk Barthel
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany
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15
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Hirschhorn T, Stockwell BR. The development of the concept of ferroptosis. Free Radic Biol Med 2019; 133:130-143. [PMID: 30268886 PMCID: PMC6368883 DOI: 10.1016/j.freeradbiomed.2018.09.043] [Citation(s) in RCA: 601] [Impact Index Per Article: 120.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 09/25/2018] [Accepted: 09/26/2018] [Indexed: 02/07/2023]
Abstract
The term ferroptosis was coined in 2012 to describe an iron-dependent regulated form of cell death caused by the accumulation of lipid-based reactive oxygen species; this type of cell death was found to have molecular characteristics distinct from other forms of regulated cell death. Features of ferroptosis have been observed periodically over the last several decades, but these molecular features were not recognized as evidence of a distinct form of cell death until recently. Here, we describe the history of observations consistent with the current definition of ferroptosis, as well as the advances that contributed to the emergence of the concept of ferroptosis. We also discuss recent implications and applications of manipulations of the ferroptotic death pathway.
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Affiliation(s)
- Tal Hirschhorn
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Brent R Stockwell
- Department of Biological Sciences, Columbia University, New York, NY, USA; Department of Chemistry, Columbia University, New York, NY, USA.
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16
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Nikseresht S, Bush AI, Ayton S. Treating Alzheimer's disease by targeting iron. Br J Pharmacol 2019; 176:3622-3635. [PMID: 30632143 DOI: 10.1111/bph.14567] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 10/14/2018] [Accepted: 11/27/2018] [Indexed: 12/30/2022] Open
Abstract
No disease modifying drugs have been approved for Alzheimer's disease despite recent major investments by industry and governments throughout the world. The burden of Alzheimer's disease is becoming increasingly unsustainable, and given the last decade of clinical trial failures, a renewed understanding of the disease mechanism is called for, and trialling of new therapeutic approaches to slow disease progression is warranted. Here, we review the evidence and rational for targeting brain iron in Alzheimer's disease. Although iron elevation in Alzheimer's disease was reported in the 1950s, renewed interest has been stimulated by the advancement of fluid and imaging biomarkers of brain iron that predict disease progression, and the recent discovery of the iron-dependent cell death pathway termed ferroptosis. We review these emerging clinical and biochemical findings and propose how this pathway may be targeted therapeutically to slow Alzheimer's disease progression. LINKED ARTICLES: This article is part of a themed section on Therapeutics for Dementia and Alzheimer's Disease: New Directions for Precision Medicine. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.18/issuetoc.
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Affiliation(s)
- Sara Nikseresht
- The Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Ashley I Bush
- The Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Scott Ayton
- The Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
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17
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Morris G, Berk M, Maes M, Puri BK. Could Alzheimer's Disease Originate in the Periphery and If So How So? Mol Neurobiol 2019; 56:406-434. [PMID: 29705945 PMCID: PMC6372984 DOI: 10.1007/s12035-018-1092-y] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Accepted: 04/17/2018] [Indexed: 12/11/2022]
Abstract
The classical amyloid cascade model for Alzheimer's disease (AD) has been challenged by several findings. Here, an alternative molecular neurobiological model is proposed. It is shown that the presence of the APOE ε4 allele, altered miRNA expression and epigenetic dysregulation in the promoter region and exon 1 of TREM2, as well as ANK1 hypermethylation and altered levels of histone post-translational methylation leading to increased transcription of TNFA, could variously explain increased levels of peripheral and central inflammation found in AD. In particular, as a result of increased activity of triggering receptor expressed on myeloid cells 2 (TREM-2), the presence of the apolipoprotein E4 (ApoE4) isoform, and changes in ANK1 expression, with subsequent changes in miR-486 leading to altered levels of protein kinase B (Akt), mechanistic (previously mammalian) target of rapamycin (mTOR) and signal transducer and activator of transcription 3 (STAT3), all of which play major roles in microglial activation, proliferation and survival, there is activation of microglia, leading to the subsequent (further) production of cytokines, chemokines, nitric oxide, prostaglandins, reactive oxygen species, inducible nitric oxide synthase and cyclooxygenase-2, and other mediators of inflammation and neurotoxicity. These changes are associated with the development of amyloid and tau pathology, mitochondrial dysfunction (including impaired activity of the electron transport chain, depleted basal mitochondrial potential and oxidative damage to key tricarboxylic acid enzymes), synaptic dysfunction, altered glycogen synthase kinase-3 (GSK-3) activity, mTOR activation, impairment of autophagy, compromised ubiquitin-proteasome system, iron dyshomeostasis, changes in APP translation, amyloid plaque formation, tau hyperphosphorylation and neurofibrillary tangle formation.
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Affiliation(s)
- Gerwyn Morris
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, P.O. Box 291, Geelong, Victoria, Australia
| | - Michael Berk
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, P.O. Box 291, Geelong, Victoria, Australia
- Department of Psychiatry, Level 1 North, Main Block, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- Florey Institute for Neuroscience and Mental Health, Kenneth Myer Building, University of Melbourne, 30 Royal Parade, Parkville, Victoria, Australia
- Orygen, The National Centre of Excellence in Youth Mental Health, 35 Poplar Rd, Parkville, Victoria, Australia
| | - Michael Maes
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, P.O. Box 291, Geelong, Victoria, Australia
- Department of Psychiatry, Chulalongkorn University, Bangkok, Thailand
| | - Basant K Puri
- Department of Medicine, Hammersmith Hospital, Imperial College London, London, UK.
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18
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Belaidi AA, Gunn AP, Wong BX, Ayton S, Appukuttan AT, Roberts BR, Duce JA, Bush AI. Marked Age-Related Changes in Brain Iron Homeostasis in Amyloid Protein Precursor Knockout Mice. Neurotherapeutics 2018; 15:1055-1062. [PMID: 30112699 PMCID: PMC6277293 DOI: 10.1007/s13311-018-0656-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
Proteolytic cleavage of the amyloid precursor protein (APP) into the Aβ peptide has been an extensively researched mechanism for Alzheimer's disease, but the normal function of the protein is less understood. APP functions to regulate neuronal iron content by stabilizing the surface presentation of ferroportin-the only iron exporter channel of cells. The present study aims to quantify the contribution of APP to brain and peripheral iron by examining the lifetime impact on brain and liver iron levels in APP knockout mice. Consistent with previous reports, we found that wild-type mice exhibited an age-dependent increase in iron and ferritin in the brain, while no age-dependent changes were observed in the liver. APP ablation resulted in an exaggeration of age-dependent iron accumulation in the brain and liver in mice that was assessed at 8, 12, 18, and 22 months of age. Brain ferroportin levels were decreased in APP knockout mice, consistent with a mechanistic role for APP in stabilizing this iron export protein in the brain. Iron elevation in the brain and liver of APP knockout mice correlated with decreased transferrin receptor 1 and increased ferritin protein levels. However, no age-dependent increase in brain ferritin iron saturation was observed in APP-KO mice despite similar protein expression levels potentially explaining the vulnerability of APP-KO mice to parkinsonism and traumatic brain sequelae. Our results support a crucial role of APP in regulating brain and peripheral iron, and show that APP may act to oppose brain iron elevation during aging.
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Affiliation(s)
- Abdel A Belaidi
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, 30 Royal Parade, Parkville, 3052, Victoria, Australia
| | - Adam P Gunn
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, 30 Royal Parade, Parkville, 3052, Victoria, Australia
| | - Bruce X Wong
- Alzheimer's Research UK Cambridge Drug Discovery Institute, University of Cambridge, Island Research Building, Cambridge Biomedical Campus, Hills Road, Cambridge, UK
| | - Scott Ayton
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, 30 Royal Parade, Parkville, 3052, Victoria, Australia
| | - Ambili T Appukuttan
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, 30 Royal Parade, Parkville, 3052, Victoria, Australia
| | - Blaine R Roberts
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, 30 Royal Parade, Parkville, 3052, Victoria, Australia
| | - James A Duce
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, 30 Royal Parade, Parkville, 3052, Victoria, Australia
- Alzheimer's Research UK Cambridge Drug Discovery Institute, University of Cambridge, Island Research Building, Cambridge Biomedical Campus, Hills Road, Cambridge, UK
| | - Ashley I Bush
- Melbourne Dementia Research Centre, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, 30 Royal Parade, Parkville, 3052, Victoria, Australia.
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19
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Tang X, Cai F, Ding DX, Zhang LL, Cai XY, Fang Q. Magnetic resonance imaging relaxation time in Alzheimer's disease. Brain Res Bull 2018; 140:176-189. [PMID: 29738781 DOI: 10.1016/j.brainresbull.2018.05.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 04/18/2018] [Accepted: 05/04/2018] [Indexed: 12/26/2022]
Abstract
The magnetic resonance imaging (MRI) relaxation time constants, T1 and T2, are sensitive to changes in brain tissue microstructure integrity. Quantitative T1 and T2 relaxation times have been proposed to serve as non-invasive biomarkers of Alzheimer's disease (AD), in which alterations are believed to not only reflect AD-related neuropathology but also cognitive impairment. In this review, we summarize the applications and key findings of MRI techniques in the context of both AD subjects and AD transgenic mouse models. Furthermore, the possible mechanisms of relaxation time alterations in AD will be discussed. Future studies could focus on relaxation time alterations in the early stage of AD, and longitudinal studies are needed to further explore relaxation time alterations during disease progression.
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Affiliation(s)
- Xiang Tang
- Department of Neurology, The First Affiliated Hospital of Soochow University, No. 899, Pinghai Road, Suzhou, Jiangsu 215006, China
| | - Feng Cai
- Department of Orthopedics, The First Affiliated Hospital of Soochow University, No. 899, Pinghai Road, Suzhou, Jiangsu 215006, China
| | - Dong-Xue Ding
- Department of Neurology, The First Affiliated Hospital of Soochow University, No. 899, Pinghai Road, Suzhou, Jiangsu 215006, China
| | - Lu-Lu Zhang
- Department of Neurology, The First Affiliated Hospital of Soochow University, No. 899, Pinghai Road, Suzhou, Jiangsu 215006, China
| | - Xiu-Ying Cai
- Department of Neurology, The First Affiliated Hospital of Soochow University, No. 899, Pinghai Road, Suzhou, Jiangsu 215006, China.
| | - Qi Fang
- Department of Neurology, The First Affiliated Hospital of Soochow University, No. 899, Pinghai Road, Suzhou, Jiangsu 215006, China.
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20
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Abstract
Magnetic resonance images are obtained by a combination of different radiofrequency pulses and gradient waveforms applied to the subject inside a magnetic field. There are multiple pulse sequences used in clinical and preclinical studies adjusted to whatever physician or researches want to analyze, from basic anatomic images to accurate diagnostic techniques as diffusion, perfusion, or functional imaging. In this chapter, we present the most used radiofrequency pulse combinations of the two groups of sequences available in magnetic resonance imaging: spin-echo and gradient-echo sequences.
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Affiliation(s)
- Daniel Calle
- Instituto de Investigaciones Biomédicas "Alberto Sols", CSIC/UAM, Madrid, Spain
| | - Teresa Navarro
- Instituto de Investigaciones Biomédicas "Alberto Sols", CSIC/UAM, Madrid, Spain.
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Why should neuroscientists worry about iron? The emerging role of ferroptosis in the pathophysiology of neuroprogressive diseases. Behav Brain Res 2017; 341:154-175. [PMID: 29289598 DOI: 10.1016/j.bbr.2017.12.036] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 12/23/2017] [Accepted: 12/27/2017] [Indexed: 12/12/2022]
Abstract
Ferroptosis is a unique form of programmed death, characterised by cytosolic accumulation of iron, lipid hydroperoxides and their metabolites, and effected by the fatal peroxidation of polyunsaturated fatty acids in the plasma membrane. It is a major driver of cell death in neurodegenerative neurological diseases. Moreover, cascades underpinning ferroptosis could be active drivers of neuropathology in major psychiatric disorders. Oxidative and nitrosative stress can adversely affect mechanisms and proteins governing cellular iron homeostasis, such as the iron regulatory protein/iron response element system, and can ultimately be a source of abnormally high levels of iron and a source of lethal levels of lipid membrane peroxidation. Furthermore, neuroinflammation leads to the upregulation of divalent metal transporter1 on the surface of astrocytes, microglia and neurones, making them highly sensitive to iron overload in the presence of high levels of non-transferrin-bound iron, thereby affording such levels a dominant role in respect of the induction of iron-mediated neuropathology. Mechanisms governing systemic and cellular iron homeostasis, and the related roles of ferritin and mitochondria are detailed, as are mechanisms explaining the negative regulation of ferroptosis by glutathione, glutathione peroxidase 4, the cysteine/glutamate antiporter system, heat shock protein 27 and nuclear factor erythroid 2-related factor 2. The potential role of DJ-1 inactivation in the precipitation of ferroptosis and the assessment of lipid peroxidation are described. Finally, a rational approach to therapy is considered, with a discussion on the roles of coenzyme Q10, iron chelation therapy, in the form of deferiprone, deferoxamine (desferrioxamine) and deferasirox, and N-acetylcysteine.
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Ammari M, Elferchichi M, Othman H, Sakly M, Abdelmelek H. Effect of sub-chronic ferrous sulfate treatment on motor skills, hematological and biochemical parameters in rats. ARCHIVES OF ENVIRONMENTAL & OCCUPATIONAL HEALTH 2017; 74:179-184. [PMID: 29068786 DOI: 10.1080/19338244.2017.1395788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 10/17/2017] [Indexed: 06/07/2023]
Abstract
This study investigated the effects of ferrous sulfate (FeSO4) on motor skills, hematological and biochemical parameters in rats. Adult rats were treated with dose of iron (280 mg/L, per os) for 15 consecutive days in drinking water. No significant difference was noticed for the motor skills in the stationary beam (p = 0.23) and suspended string tests (p = 0.48) between control and iron-treated rats. However, iron-treated rats showed a significant increase in white blood cells count (p = 0.01), mean corpuscular volume values (p = 0.02) and decrease in frequency of peristaltic contractions of the fragment of the intestine (in vitro) compared to control rats (p = 0.01). No significant difference in plasma iron level (p = 0.89) and transferrin amount were observed after iron treatment (p = 0.65). The findings indicate that iron treatment at 280 mg/L, per os for 15 consecutive days in adult rats induced increase of hematological parameters (sign of a potential inflammation), but not motor skills deficit.
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Affiliation(s)
- Mohamed Ammari
- a Laboratory of Integrative Physiology , Faculty of Sciences of Bizerte, University of Carthage , Zarzouna , Tunisia
- b Higher Institute of Applied Biological Sciences of Tunis, University of Tunis El Manar , Tunis , Tunisia
| | - Miryam Elferchichi
- a Laboratory of Integrative Physiology , Faculty of Sciences of Bizerte, University of Carthage , Zarzouna , Tunisia
| | - Haifa Othman
- a Laboratory of Integrative Physiology , Faculty of Sciences of Bizerte, University of Carthage , Zarzouna , Tunisia
| | - Mohsen Sakly
- a Laboratory of Integrative Physiology , Faculty of Sciences of Bizerte, University of Carthage , Zarzouna , Tunisia
| | - Hafedh Abdelmelek
- a Laboratory of Integrative Physiology , Faculty of Sciences of Bizerte, University of Carthage , Zarzouna , Tunisia
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Tariq S, Barber PA. Dementia risk and prevention by targeting modifiable vascular risk factors. J Neurochem 2017; 144:565-581. [PMID: 28734089 DOI: 10.1111/jnc.14132] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 06/23/2017] [Accepted: 07/15/2017] [Indexed: 01/04/2023]
Abstract
The incidence of dementia is expected to double in the next 20 years and will contribute to heavy social and economic burden. Dementia is caused by neuronal loss that leads to brain atrophy years before symptoms manifest. Currently, no cure exists and extensive efforts are being made to mitigate cognitive impairment in late life in order to reduce the burden on patients, caregivers, and society. The most common type of dementia, Alzheimer's disease (AD), and vascular dementia (VaD) often co-exists in the brain and shares common, modifiable risk factors, which are targeted in numerous secondary prevention trials. There is a growing need for non-pharmacological interventions and infrastructural support from governments to encourage psychosocial and behavioral interventions. Secondary prevention trials need to be redesigned based on the risk profile of individual subjects, which require the use of validated and standardized clinical, biological, and neuroimaging biomarkers. Multi-domain approaches have been proposed in high-risk populations that target optimal treatment; clinical trials need to recruit individuals at the highest risk of dementia before symptoms develop, thereby identifying an enriched disease group to test preventative and disease modifying strategies. The underlying aim should be to reduce microscopic brain tissue loss by modifying vascular and lifestyle risk factors over a relatively short period of time, thus optimizing the opportunity for preventing dementia in the future. Collaboration between international research groups is of key importance to the optimal use and allocation of existing resources, and the development of new techniques in preventing dementia. This article is part of the Special Issue "Vascular Dementia".
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Affiliation(s)
- Sana Tariq
- Seaman Family MR Center, Foothills Medical Centre, Calgary, AB, Canada.,Hotchkiss Brain Institute, Foothills Medical Center, Room 1A10 Health Research Innovation Center, Calgary, AB, Canada
| | - Philip A Barber
- Hotchkiss Brain Institute, Foothills Medical Center, Room 1A10 Health Research Innovation Center, Calgary, AB, Canada.,Calgary Stroke Program, Department of Clinical Neurosciences, Foothills Medical Centre, Calgary, AB, Canada
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Guan X, Xu X, Zhang M. Region-Specific Iron Measured by MRI as a Biomarker for Parkinson's Disease. Neurosci Bull 2017; 33:561-567. [PMID: 28516282 DOI: 10.1007/s12264-017-0138-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 03/20/2017] [Indexed: 12/24/2022] Open
Abstract
The identification of sensitive and specific biomarkers for Parkinson's disease (PD) poses an important clinical challenge. A potential biomarker for early diagnosis and disease monitoring of PD is region-specific iron. Iron accumulation in the substantia nigra pars compacta is considered a main characteristic of PD. However, questions remain, such as the relationship between nigral iron and clinical indices of PD (motor impairment or disease duration). Further, previous studies have suggested the influence of iron on other nuclei. Iron quantification using magnetic resonance imaging (MRI) allows for studies of the relationship between regional iron and clinical symptoms in vivo. Thus, in this review we discuss the following topics: the technological development of MRI in measuring brain iron, nigral iron as a potential marker for PD in both clinical and prodromal stages, other influences of regional iron on PD, and clinical translation and future perspectives.
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Affiliation(s)
- Xiaojun Guan
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China
| | - Xiaojun Xu
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China
| | - Minming Zhang
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China.
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Wang P, Wang ZY. Metal ions influx is a double edged sword for the pathogenesis of Alzheimer's disease. Ageing Res Rev 2017; 35:265-290. [PMID: 27829171 DOI: 10.1016/j.arr.2016.10.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Revised: 09/08/2016] [Accepted: 10/17/2016] [Indexed: 12/17/2022]
Abstract
Alzheimer's disease (AD) is a common form of dementia in aged people, which is defined by two pathological characteristics: β-amyloid protein (Aβ) deposition and tau hyperphosphorylation. Although the mechanisms of AD development are still being debated, a series of evidence supports the idea that metals, such as copper, iron, zinc, magnesium and aluminium, are involved in the pathogenesis of the disease. In particular, the processes of Aβ deposition in senile plaques (SP) and the inclusion of phosphorylated tau in neurofibrillary tangles (NFTs) are markedly influenced by alterations in the homeostasis of the aforementioned metal ions. Moreover, the mechanisms of oxidative stress, synaptic plasticity, neurotoxicity, autophagy and apoptosis mediate the effects of metal ions-induced the aggregation state of Aβ and phosphorylated tau on AD development. More importantly, imbalance of these mechanisms finally caused cognitive decline in different experiment models. Collectively, reconstructing the signaling network that regulates AD progression by metal ions may provide novel insights for developing chelators specific for metal ions to combat AD.
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Affiliation(s)
- Pu Wang
- College of Life and Health Sciences, Northeastern University, No. 3-11, Wenhua Road, Shenyang, 110819, PR China.
| | - Zhan-You Wang
- College of Life and Health Sciences, Northeastern University, No. 3-11, Wenhua Road, Shenyang, 110819, PR China.
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26
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Xiong XY, Liu L, Wang FX, Yang YR, Hao JW, Wang PF, Zhong Q, Zhou K, Xiong A, Zhu WY, Zhao T, Meng ZY, Wang YC, Gong QW, Liao MF, Wang J, Yang QW. Toll-Like Receptor 4/MyD88-Mediated Signaling of Hepcidin Expression Causing Brain Iron Accumulation, Oxidative Injury, and Cognitive Impairment After Intracerebral Hemorrhage. Circulation 2016; 134:1025-1038. [PMID: 27576776 DOI: 10.1161/circulationaha.116.021881] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 07/27/2016] [Indexed: 12/21/2022]
Abstract
BACKGROUND Disturbance of brain iron metabolism after intracerebral hemorrhage (ICH) results in oxidative brain injury and cognition impairment. Hepcidin plays an important role in regulating iron metabolism, and we have reported that serum hepcidin is positively correlated with poor outcomes in patients with ICH. However, the roles of hepcidin in brain iron metabolism after ICH remain largely unknown. METHODS Parabiosis and ICH models combined with in vivo and in vitro experiments were used to investigate the roles of hepcidin in brain iron metabolism after ICH. RESULTS Increased hepcidin-25 was found in serum and primarily in astrocytes after ICH. The brain iron efflux, oxidative brain injury, and cognition impairment were improved in Hepc-/- ICH mice but aggravated by the human hepcidin-25 peptide in C57BL/6 ICH mice. Data obtained in in vitro studies showed that increased hepcidin inhibited the intracellular iron efflux of brain microvascular endothelial cells but was rescued by a hepcidin antagonist, fursultiamine. Using parabiosis ICH models also shows that increased serum hepcidin prevents brain iron efflux. In addition, Toll-like receptor 4 (TLR4)/MyD88 signaling pathway increased hepcidin expression by promoting interleukin-6 expression and signal transducer and activator of transcription 3 phosphorylation. TLR4-/- and MyD88-/- mice exhibited improvement in brain iron efflux at 7, 14, and 28 days after ICH, and the TLR4 antagonist (6R)-6-[N-(2-chloro-4-fluorophenyl) sulfamoyl] cyclohex-1-ene-1-carboxylate significantly decreased brain iron levels at days 14 and 28 after ICH and improved cognition impairment at day 28. CONCLUSIONS The results presented here show that increased hepcidin expression caused by inflammation prevents brain iron efflux via inhibition of the intracellular iron efflux of brain microvascular endothelial cells entering into circulation and aggravating oxidative brain injury and cognition impairment, which identifies a mechanistic target for muting inflammation to promote brain iron efflux and to attenuate oxidative brain injury after ICH.
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Affiliation(s)
- Xiao-Yi Xiong
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Liang Liu
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Fa-Xiang Wang
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Yuan-Rui Yang
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Jun-Wei Hao
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Peng-Fei Wang
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Qi Zhong
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Kai Zhou
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Ao Xiong
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Wen-Yao Zhu
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Ting Zhao
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Zhao-You Meng
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Yan-Chun Wang
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Qiu-Wen Gong
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Mao-Fan Liao
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Jian Wang
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.)
| | - Qing-Wu Yang
- From Department of Neurology, Xinqiao Hospital, Third Military Medical University, Shapingba District, Chongqing, China (X.-Y.X., L.L., F.-X.W., Y.-R.Y., Q.Z., K.Z., W.-Y.Z., T.Z., Z.-Y.M., Y.-C.W., Q.-W.G., M.-F.L., Q.-W.Y.); Department of Neurology, Key Laboratory of Neurorepair and Regeneration, Tianjin and Ministry of Education, Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin, China (J.-W.H.); Department of Neurology, Weihai Municipal Hospital, Weihai, China (P.-F.W.); Basic Medical College, Zhengzhou University, Zhengzhou, China (A.X.); and Department of Anesthesiology/Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD (J.W.).
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Knight MJ, McCann B, Tsivos D, Dillon S, Coulthard E, Kauppinen RA. Quantitative T2 mapping of white matter: applications for ageing and cognitive decline. Phys Med Biol 2016; 61:5587-605. [PMID: 27384985 PMCID: PMC5390949 DOI: 10.1088/0031-9155/61/15/5587] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In MRI, the coherence lifetime T2 is sensitive to the magnetic environment imposed by tissue microstructure and biochemistry in vivo. Here we explore the possibility that the use of T2 relaxometry may provide information complementary to that provided by diffusion tensor imaging (DTI) in ageing of healthy controls (HC), Alzheimer’s disease (AD) and mild cognitive impairment (MCI). T2 and diffusion MRI metrics were quantified in HC and patients with MCI and mild AD using multi-echo MRI and DTI. We used tract-based spatial statistics (TBSS) to evaluate quantitative MRI parameters in white matter (WM). A prolonged T2 in WM was associated with AD, and able to distinguish AD from MCI, and AD from HC. Shorter WM T2 was associated with better cognition and younger age in general. In no case was a reduction in T2 associated with poorer cognition. We also applied principal component analysis, showing that WM volume changes independently of T2, MRI diffusion indices and cognitive performance indices. Our data add to the evidence that age-related and AD-related decline in cognition is in part attributable to WM tissue state, and much less to WM quantity. These observations suggest that WM is involved in AD pathology, and that T2 relaxometry is a potential imaging modality for detecting and characterising WM in cognitive decline and dementia.
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Affiliation(s)
- Michael J Knight
- School of Experimental Psychology, 12a Priory Road, University of Bristol, Bristol, BS8 1TU, UK
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Belaidi AA, Bush AI. Iron neurochemistry in Alzheimer's disease and Parkinson's disease: targets for therapeutics. J Neurochem 2016; 139 Suppl 1:179-197. [DOI: 10.1111/jnc.13425] [Citation(s) in RCA: 324] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 10/24/2015] [Accepted: 11/03/2015] [Indexed: 12/12/2022]
Affiliation(s)
- Abdel A. Belaidi
- The Florey Institute for Neuroscience and Mental Health; The University of Melbourne; Parkville Vic. Australia
| | - Ashley I. Bush
- The Florey Institute for Neuroscience and Mental Health; The University of Melbourne; Parkville Vic. Australia
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The Role of Oxidative Stress-Induced Epigenetic Alterations in Amyloid-β Production in Alzheimer's Disease. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:604658. [PMID: 26543520 PMCID: PMC4620382 DOI: 10.1155/2015/604658] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 12/15/2014] [Indexed: 11/17/2022]
Abstract
An increasing number of studies have proposed a strong correlation between reactive oxygen species (ROS)-induced oxidative stress (OS) and the pathogenesis of Alzheimer's disease (AD). With over five million people diagnosed in the United States alone, AD is the most common type of dementia worldwide. AD includes progressive neurodegeneration, followed by memory loss and reduced cognitive ability. Characterized by the formation of amyloid-beta (Aβ) plaques as a hallmark, the connection between ROS and AD is compelling. Analyzing the ROS response of essential proteins in the amyloidogenic pathway, such as amyloid-beta precursor protein (APP) and beta-secretase (BACE1), along with influential signaling programs of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and c-Jun N-terminal kinase (JNK), has helped visualize the path between OS and Aβ overproduction. In this review, attention will be paid to significant advances in the area of OS, epigenetics, and their influence on Aβ plaque assembly. Additionally, we aim to discuss available treatment options for AD that include antioxidant supplements, Asian traditional medicines, metal-protein-attenuating compounds, and histone modifying inhibitors.
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Qin YY, Li YP, Zhang S, Xiong Y, Guo LY, Yang SQ, Yao YH, Li W, Zhu WZ. Frequency-specific alterations of large-scale functional brain networks in patients with Alzheimer's disease. Chin Med J (Engl) 2015; 128:602-9. [PMID: 25698190 PMCID: PMC4834769 DOI: 10.4103/0366-6999.151654] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Previous studies have indicated that the cognitive deficits in patients with Alzheimer's disease (AD) may be due to topological deteriorations of the brain network. However, whether the selection of a specific frequency band could impact the topological properties is still not clear. Our hypothesis is that the topological properties of AD patients are also frequency-specific. METHODS Resting state functional magnetic resonance imaging data from 10 right-handed moderate AD patients (mean age: 64.3 years; mean mini mental state examination [MMSE]: 18.0) and 10 age and gender-matched healthy controls (mean age: 63.6 years; mean MMSE: 28.2) were enrolled in this study. The global efficiency, the clustering coefficient (CC), the characteristic path length (CpL), and "small-world" property were calculated in a wide range of thresholds and averaged within each group, at three different frequency bands (0.01-0.06 Hz, 0.06-0.11 Hz, and 0.11-0.25 Hz). RESULTS At lower-frequency bands (0.01-0.06 Hz, 0.06-0.11 Hz), the global efficiency, the CC and the "small-world" properties of AD patients decreased compared to controls. While at higher-frequency bands (0.11-0.25 Hz), the CpL was much longer, and the "small-world" property was disrupted in AD, particularly at a higher threshold. The topological properties changed with different frequency bands, suggesting the existence of disrupted global and local functional organization associated with AD. CONCLUSIONS This study demonstrates that the topological alterations of large-scale functional brain networks in AD patients are frequency dependent, thus providing fundamental support for optimal frequency selection in future related research.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Wen-Zhen Zhu
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
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Appraising the Role of Iron in Brain Aging and Cognition: Promises and Limitations of MRI Methods. Neuropsychol Rev 2015; 25:272-87. [PMID: 26248580 DOI: 10.1007/s11065-015-9292-y] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 07/24/2015] [Indexed: 12/11/2022]
Abstract
Age-related increase in frailty is accompanied by a fundamental shift in cellular iron homeostasis. By promoting oxidative stress, the intracellular accumulation of non-heme iron outside of binding complexes contributes to chronic inflammation and interferes with normal brain metabolism. In the absence of direct non-invasive biomarkers of brain oxidative stress, iron accumulation estimated in vivo may serve as its proxy indicator. Hence, developing reliable in vivo measurements of brain iron content via magnetic resonance imaging (MRI) is of significant interest in human neuroscience. To date, by estimating brain iron content through various MRI methods, significant age differences and age-related increases in iron content of the basal ganglia have been revealed across multiple samples. Less consistent are the findings that pertain to the relationship between elevated brain iron content and systemic indices of vascular and metabolic dysfunction. Only a handful of cross-sectional investigations have linked high iron content in various brain regions and poor performance on assorted cognitive tests. The even fewer longitudinal studies indicate that iron accumulation may precede shrinkage of the basal ganglia and thus predict poor maintenance of cognitive functions. This rapidly developing field will benefit from introduction of higher-field MRI scanners, improvement in iron-sensitive and -specific acquisition sequences and post-processing analytic and computational methods, as well as accumulation of data from long-term longitudinal investigations. This review describes the potential advantages and promises of MRI-based assessment of brain iron, summarizes recent findings and highlights the limitations of the current methodology.
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Persson N, Wu J, Zhang Q, Liu T, Shen J, Bao R, Ni M, Liu T, Wang Y, Spincemaille P. Age and sex related differences in subcortical brain iron concentrations among healthy adults. Neuroimage 2015. [PMID: 26216277 DOI: 10.1016/j.neuroimage.2015.07.050] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Age and sex can influence brain iron levels. We studied the influence of these variables on deep gray matter magnetic susceptibilities. In 183 healthy volunteers (44.7 ± 14.2 years, range 20-69, ♀ 49%), in vivo quantitative susceptibility mapping (QSM) at 1.5T was performed to estimate brain iron accumulation in the following regions of interest (ROIs): caudate nucleus (Cd), putamen (Pt), globus pallidus (Gp), thalamus (Th), pulvinar (Pul), red nucleus (Rn), substantia nigra (Sn) and the cerebellar dentate nuclei (Dn). We gauged the influence of age and sex on magnetic susceptibility by specifying a series of structural equation models. The distributions of susceptibility varied in degree across the structures, conforming to histologic findings (Hallgren and Sourander, 1958), with the highest degree of susceptibility in the Gp and the lowest in the Th. Iron increase correlated across several ROIs, which may reflect an underlying age-related process. Advanced age was associated with a particularly strong linear rise of susceptibility in the striatum. Nonlinear age trends were found in the Rn, where they were the most pronounced, followed by the Pul and Sn, while minimal nonlinear trends were observed for the Pt, Th, and Dn. Moreover, sex related variations were observed, so that women showed lower levels of susceptibility in the Sn after accounting for age. Regional susceptibility of the Pul increased linearly with age in men but exhibited a nonlinear association with age in women with a leveling off starting from midlife. Women expected to be post menopause (+51 years) showed lower total magnetic susceptibility in the subcortical gray matter. The current report not only is consistent with previous reports of age related variations of brain iron, but also adds to the current knowledge by reporting age-related changes in less studied, smaller subcortical nuclei. This is the first in-vivo report to show lower total subcortical brain iron levels selectively in women from midlife, compared to men and younger women. These results encourage further assessment of sex differences in brain iron. We anticipate that age and sex are important co-factors to take into account when establishing a baseline level for differentiating pathologic neurodegeneration from healthy aging. The variations in regional susceptibility reported herein should be evaluated further using a longitudinal study design to determine within-person changes in aging.
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Affiliation(s)
- Ninni Persson
- Department of Psychology, Stockholm University, Stockholm, Sweden; Stockholm Brain Institute, Stockholm, Sweden; Radiology, Weill Cornell Medical College, New York, NY, USA
| | - Jianlin Wu
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China; Radiology, Zhongshan Hospital of Dalian University, Dalian, Liaoning Province, China
| | - Qing Zhang
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Ting Liu
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Jing Shen
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Ruyi Bao
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Mingfei Ni
- Radiology, The 1st Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Tian Liu
- Radiology, Weill Cornell Medical College, New York, NY, USA
| | - Yi Wang
- Radiology, Weill Cornell Medical College, New York, NY, USA; Biomedical Engineering, Cornell University, Ithaca, NY, USA
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Xia S, Zheng G, Shen W, Liu S, Zhang LJ, Haacke EM, Lu GM. Quantitative measurements of brain iron deposition in cirrhotic patients using susceptibility mapping. Acta Radiol 2015; 56:339-46. [PMID: 24646625 DOI: 10.1177/0284185114525374] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Susceptibility-weighted imaging (SWI) has been used to detect micro-bleeds and iron deposits in the brain. However, no reports have been published on the application of SWI in studying iron changes in the brain of cirrhotic patients. PURPOSE To compare the susceptibility of different brain structures in cirrhotic patients with that in healthy controls and to evaluate susceptibility as a potential biomarker and correlate the measured susceptibility and cadaveric brain iron concentration for a variety of brain structures. MATERIAL AND METHODS Forty-three cirrhotic patients (27 men, 16 women; mean age, 50 ± 9 years) and 34 age- and sex-matched healthy controls (22 men, 12 women; mean age, 47 ± 7 years) were included in this retrospective study. Susceptibility was measured in the frontal white matter, basal ganglia, midbrain, and dentate nucleus and compared with results gathered from two postmortem brain studies. Correlation between susceptibility and clinical biomarkers and neuropsychiatric tests scores was calculated. RESULTS In cirrhotic patients, the susceptibility of left frontal white matter, bilateral caudate head, and right substantia nigra was higher than that in healthy controls (P < 0.05). There was a positive correlation between susceptibility and iron concentration from one postmortem brain study (r = 0.835, P = 0.01) in eight deep grey matter structures and another in five brain structures (r = 0.900, P = 0.03). The susceptibility of right caudate head (r = 0.402) and left caudate head (r = 0.408) correlated with neuropsychological test scores (both P < 0.05). CONCLUSION Abnormal iron deposits occur in cirrhotic patients and abnormal susceptibility of some brain regions appears to reflect neurocognitive changes.
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Affiliation(s)
- Shuang Xia
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, PR China
- Department of Medical Imaging, Tianjin First Central Hospital, Tianjin, PR China
| | - Gang Zheng
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, PR China
| | - Wen Shen
- Department of Medical Imaging, Tianjin First Central Hospital, Tianjin, PR China
| | - Saifeng Liu
- McMaster University, Hamilton, Ontario, PR China
| | - Long Jiang Zhang
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, PR China
| | - E Mark Haacke
- Department of Radiology, Wayne State University, Detroit, MI, USA
| | - Guang Ming Lu
- Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, PR China
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Wang D, Li YY, Luo JH, Li YH. Age-related iron deposition in the basal ganglia of controls and Alzheimer disease patients quantified using susceptibility weighted imaging. Arch Gerontol Geriatr 2014; 59:439-49. [PMID: 24820446 DOI: 10.1016/j.archger.2014.04.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Accepted: 04/06/2014] [Indexed: 12/24/2022]
Abstract
This study aimed to investigate age-related iron deposition changes in healthy subjects and Alzheimer disease patients using susceptibility weighted imaging. The study recruited 182 people, including 143 healthy volunteers and 39 Alzheimer disease patients. All underwent conventional magnetic resonance imaging and susceptibility weighted imaging sequences. The groups were divided according to age. Phase images were used to investigate iron deposition in the bilateral head of the caudate nucleus, globus pallidus and putamen, and the angle radian value was calculated. We hypothesized that age-related iron deposition changes may be different between Alzheimer disease patients and controls of the same age, and that susceptibility weighted imaging would be a more sensitive method of iron deposition quantification. The results revealed that iron deposition in the globus pallidus increased with age, up to 40 years. In the head of the caudate nucleus, iron deposition peaked at 60 years. There was a general increasing trend with age in the putamen, up to 50-70 years old. There was significant difference between the control and Alzheimer disease groups in the bilateral globus pallidus in both the 60-70 and 70-80 year old group comparisons. In conclusion, iron deposition increased with age in the globus pallidus, the head of the caudate nucleus and putamen, reaching a plateau at different ages. Furthermore, comparisons between the control and Alzheimer disease group revealed that iron deposition changes were more easily detected in the globus pallidus.
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Affiliation(s)
- Dan Wang
- Institute of Diagnostic and Interventional Radiology, The Sixth Affiliated People's Hospital, Shanghai Jiao Tong University, No. 600, Yi Shan Road, Shanghai 200233, China
| | - Yan-Ying Li
- The Second Affiliated Hospital of Harbin Medical University, Radiology Department, China
| | - Jian-Hua Luo
- College of Life Science and Technology, Shanghai Jiaotong University, China
| | - Yue-Hua Li
- Institute of Diagnostic and Interventional Radiology, The Sixth Affiliated People's Hospital, Shanghai Jiao Tong University, No. 600, Yi Shan Road, Shanghai 200233, China.
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Tang MY, Chen TW, Zhang XM, Huang XH. GRE T2∗-weighted MRI: principles and clinical applications. BIOMED RESEARCH INTERNATIONAL 2014; 2014:312142. [PMID: 24987676 PMCID: PMC4009216 DOI: 10.1155/2014/312142] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 03/19/2014] [Indexed: 12/20/2022]
Abstract
The sequence of a multiecho gradient recalled echo (GRE) T2*-weighted imaging (T2*WI) is a relatively new magnetic resonance imaging (MRI) technique. In contrast to T2 relaxation, which acquires a spin echo signal, T2* relaxation acquires a gradient echo signal. The sequence of a GRE T2*WI requires high uniformity of the magnetic field. GRE T2*WI can detect the smallest changes in uniformity in the magnetic field and can improve the rate of small lesion detection. In addition, the T2* value can indirectly reflect changes in tissue biochemical components. Moreover, it can be used for the early diagnosis and quantitative diagnosis of some diseases. This paper reviews the principles and clinical applications as well as the advantages and disadvantages of GRE T2*WI.
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Affiliation(s)
- Meng Yue Tang
- Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, China
| | - Tian Wu Chen
- Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, China
| | - Xiao Ming Zhang
- Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, China
| | - Xiao Hua Huang
- Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, China
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Ying J, Yan Z, Gao XR. 40 Hz auditory steady state response to linguistic features of stimuli during auditory hallucinations. ACTA ACUST UNITED AC 2013; 33:748-753. [DOI: 10.1007/s11596-013-1191-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 05/30/2013] [Indexed: 11/30/2022]
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Hare D, Ayton S, Bush A, Lei P. A delicate balance: Iron metabolism and diseases of the brain. Front Aging Neurosci 2013; 5:34. [PMID: 23874300 PMCID: PMC3715022 DOI: 10.3389/fnagi.2013.00034] [Citation(s) in RCA: 275] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 06/25/2013] [Indexed: 12/12/2022] Open
Abstract
Iron is the most abundant transition metal within the brain, and is vital for a number of cellular processes including neurotransmitter synthesis, myelination of neurons, and mitochondrial function. Redox cycling between ferrous and ferric iron is utilized in biology for various electron transfer reactions essential to life, yet this same chemistry mediates deleterious reactions with oxygen that induce oxidative stress. Consequently, there is a precise and tightly controlled mechanism to regulate iron in the brain. When iron is dysregulated, both conditions of iron overload and iron deficiencies are harmful to the brain. This review focuses on how iron metabolism is maintained in the brain, and how an alteration to iron and iron metabolism adversely affects neurological function.
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Affiliation(s)
- Dominic Hare
- The Florey Institute of Neuroscience and Mental Health, University of MelbourneVIC, Australia
- Elemental Bio-imaging Facility, University of TechnologySydney, NSW, Australia
| | - Scott Ayton
- The Florey Institute of Neuroscience and Mental Health, University of MelbourneVIC, Australia
| | - Ashley Bush
- The Florey Institute of Neuroscience and Mental Health, University of MelbourneVIC, Australia
| | - Peng Lei
- The Florey Institute of Neuroscience and Mental Health, University of MelbourneVIC, Australia
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Yu JX, Hallac RR, Chiguru S, Mason RP. New frontiers and developing applications in 19F NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2013; 70:25-49. [PMID: 23540575 PMCID: PMC3613763 DOI: 10.1016/j.pnmrs.2012.10.001] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 10/23/2012] [Indexed: 05/06/2023]
Affiliation(s)
- Jian-Xin Yu
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| | - Rami R. Hallac
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| | - Srinivas Chiguru
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
| | - Ralph P. Mason
- Laboratory of Prognostic Radiology, Division of Advanced Radiological Sciences, Department of Radiology, UT Southwestern Medical Center, Dallas, Texas
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Wang D, Li WB, Wei XE, Li YH, Dai YM. An investigation of age-related iron deposition using susceptibility weighted imaging. PLoS One 2012; 7:e50706. [PMID: 23226360 PMCID: PMC3511361 DOI: 10.1371/journal.pone.0050706] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 10/24/2012] [Indexed: 01/02/2023] Open
Abstract
Aim To quantify age-dependent iron deposition changes in healthy subjects using Susceptibility Weighted Imaging (SWI). Materials and Methods In total, 143 healthy volunteers were enrolled. All underwent conventional MR and SWI sequences. Subjects were divided into eight groups according to age. Using phase images to quantify iron deposition in the head of the caudate nucleus and the lenticular nucleus, the angle radian value was calculated and compared between groups. ANOVA/Pearson correlation coefficient linear regression analysis and polynomial fitting were performed to analyze the relationship between iron deposition in the head of the caudate nucleus and lenticular nucleus with age. Results Iron deposition in the lenticular nucleus increased in individuals aged up to 40 years, but did not change in those aged over 40 years once a peak had been reached. In the head of the caudate nucleus, iron deposition peaked at 60 years (p<0.05). The correlation coefficients for iron deposition in the L-head of the caudate nucleus, R-head of the caudate nucleus, L-lenticular nucleus and R-lenticular nucleus with age were 0.67691, 0.48585, 0.5228 and 0.5228 (p<0.001, respectively). Linear regression analyses showed a significant correlation between iron deposition levels in with age groups. Conclusions Iron deposition in the lenticular nucleus was found to increase with age, reaching a plateau at 40 years. Iron deposition in the head of the caudate nucleus also increased with age, reaching a plateau at 60 years.
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Affiliation(s)
- Dan Wang
- Institute of Diagnostic and Interventional Radiology, The Sixth Affiliated People’s Hospital, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Wen-Bin Li
- Institute of Diagnostic and Interventional Radiology, The Sixth Affiliated People’s Hospital, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Xiao-Er Wei
- Institute of Diagnostic and Interventional Radiology, The Sixth Affiliated People’s Hospital, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Yue-Hua Li
- Institute of Diagnostic and Interventional Radiology, The Sixth Affiliated People’s Hospital, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
- * E-mail:
| | - Yong-Ming Dai
- Siemens MRI Technique Support Department, German Siemens Healthcare MR Clinical Application, Shanghai, People’s Republic of China
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The bad, the good, and the ugly about oxidative stress. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2012; 2012:163913. [PMID: 22619696 PMCID: PMC3350994 DOI: 10.1155/2012/163913] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2011] [Revised: 01/16/2012] [Accepted: 02/07/2012] [Indexed: 01/07/2023]
Abstract
Alzheimer's disease (AD), Parkinson's disease (PD), and cancer (e.g., leukemia) are the most devastating disorders affecting millions of people worldwide. Except for some kind of cancers, no effective and/or definitive therapeutic treatment aimed to reduce or to retard the clinic and pathologic symptoms induced by AD and PD is presently available. Therefore, it is urgently needed to understand the molecular basis of these disorders. Since oxidative stress (OS) is an important etiologic factor of the pathologic process of AD, PD, and cancer, understanding how intracellular signaling pathways respond to OS will have a significant implication in the therapy of these diseases. Here, we propose a model of minimal completeness of cell death signaling induced by OS as a mechanistic explanation of neuronal and cancer cell demise. This mechanism might provide the basis for therapeutic design strategies. Finally, we will attempt to associate PD, cancer, and OS. This paper critically analyzes the evidence that support the “oxidative stress model” in neurodegeneration and cancer.
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Ortíz-Estrada G, Luna-Castro S, Piña-Vázquez C, Samaniego-Barrón L, León-Sicairos N, Serrano-Luna J, de la Garza M. Iron-saturated lactoferrin and pathogenic protozoa: could this protein be an iron source for their parasitic style of life? Future Microbiol 2012; 7:149-64. [PMID: 22191452 DOI: 10.2217/fmb.11.140] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Iron is an essential nutrient for the survival of pathogens inside a host. As a general strategy against microbes, mammals have evolved complex iron-withholding systems for efficiently decreasing the iron accessible to invaders. Pathogens that inhabit the respiratory, intestinal and genitourinary tracts encounter an iron-deficient environment on the mucosal surface, where ferric iron is chelated by lactoferrin, an extracellular glycoprotein of the innate immune system. However, parasitic protozoa have developed several mechanisms to obtain iron from host holo-lactoferrin. Tritrichomonas fetus, Trichomonas vaginalis, Toxoplasma gondii and Entamoeba histolytica express lactoferrin-binding proteins and use holo-lactoferrin as an iron source for growth in vitro; in some species, these binding proteins are immunogenic and, therefore, may serve as potential vaccine targets. Another mechanism to acquire lactoferrin iron has been reported in Leishmania spp. promastigotes, which use a surface reductase to recognize and reduce ferric iron to the accessible ferrous form. Cysteine proteases that cleave lactoferrin have been reported in E. histolytica. This review summarizes the available information on how parasites uptake and use the iron from lactoferrin to survive in hostile host environments.
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Affiliation(s)
- Guillermo Ortíz-Estrada
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del IPN, Apdo. 14-740, México DF 07000, México
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Warsi MA, Molloy W, Noseworthy MD. Correlating brain blood oxygenation level dependent (BOLD) fractal dimension mapping with magnetic resonance spectroscopy (MRS) in Alzheimer's disease. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2012; 25:335-44. [PMID: 22446877 DOI: 10.1007/s10334-012-0312-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 02/15/2012] [Accepted: 03/02/2012] [Indexed: 11/29/2022]
Abstract
OBJECTIVES To correlate temporal fractal structure of resting state blood oxygen level dependent (rsBOLD) functional magnetic resonance imaging (fMRI) with in vivo proton magnetic resonance spectroscopy ((1)H-MRS), in Alzheimer's disease (AD) and healthy age-matched normal controls (NC). MATERIALS AND METHODS High temporal resolution (4 Hz) rsBOLD signal and single voxel (left putamen) magnetic resonance spectroscopy data was acquired in 33 AD patients and 13 NC. The rsBOLD data was analyzed using two types of fractal dimension (FD) analysis based on relative dispersion and frequency power spectrum. Comparisons in FD were performed between AD and NC, and FD measures were correlated with (1)H-MRS findings. RESULTS Temporal fractal analysis of rsBOLD, was able to differentiate AD from NC subjects (P = 0.03). Low FD correlated with markers of AD severity including decreased concentrations of N-acetyl aspartate (R = 0.44, P = 0.015) and increased myoinositol (mI) (R = -0.45, P = 0.012). CONCLUSION Based on these results we suggest fractal analysis of rsBOLD could provide an early marker of AD.
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Affiliation(s)
- Mohammed A Warsi
- School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada
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Neurodegeneration in Alzheimer disease: role of amyloid precursor protein and presenilin 1 intracellular signaling. J Toxicol 2012; 2012:187297. [PMID: 22496686 PMCID: PMC3306972 DOI: 10.1155/2012/187297] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 10/14/2011] [Accepted: 10/26/2011] [Indexed: 01/02/2023] Open
Abstract
Alzheimer disease (AD) is a heterogeneous neurodegenerative disorder characterized by (1) progressive loss of synapses and neurons, (2) intracellular neurofibrillary tangles, composed of hyperphosphorylated Tau protein, and (3) amyloid plaques. Genetically, AD is linked to mutations in few proteins amyloid precursor protein (APP) and presenilin 1 and 2 (PS1 and PS2). The molecular mechanisms underlying neurodegeneration in AD as well as the physiological function of APP are not yet known. A recent theory has proposed that APP and PS1 modulate intracellular signals to induce cell-cycle abnormalities responsible for neuronal death and possibly amyloid deposition. This hypothesis is supported by the presence of a complex network of proteins, clearly involved in the regulation of signal transduction mechanisms that interact with both APP and PS1. In this review we discuss the significance of novel finding related to cell-signaling events modulated by APP and PS1 in the development of neurodegeneration.
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