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Carling GK, Fan L, Foxe NR, Norman K, Ye P, Wong MY, Zhu D, Yu F, Xu J, Yarahmady A, Chen H, Huang Y, Amin S, Zacharioudakis E, Chen X, Holtzman DM, Mok SA, Gavathiotis E, Sinha SC, Cheng F, Luo W, Gong S, Gan L. Alzheimer's disease-linked risk alleles elevate microglial cGAS-associated senescence and neurodegeneration in a tauopathy model. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.24.577107. [PMID: 38328219 PMCID: PMC10849737 DOI: 10.1101/2024.01.24.577107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
The strongest risk factors for Alzheimer's disease (AD) include the χ4 allele of apolipoprotein E (APOE), the R47H variant of triggering receptor expressed on myeloid cells 2 (TREM2), and female sex. Here, we combine APOE4 and TREM2R47H ( R47H ) in female P301S tauopathy mice to identify the pathways activated when AD risk is the strongest, thereby highlighting disease-causing mechanisms. We find that the R47H variant induces neurodegeneration in female APOE4 mice without impacting hippocampal tau load. The combination of APOE4 and R47H amplified tauopathy-induced cell-autonomous microglial cGAS-STING signaling and type-I interferon response, and interferon signaling converged across glial cell types in the hippocampus. APOE4-R47H microglia displayed cGAS- and BAX-dependent upregulation of senescence, showing association between neurotoxic signatures and implicating mitochondrial permeabilization in pathogenesis. By uncovering pathways enhanced by the strongest AD risk factors, our study points to cGAS-STING signaling and associated microglial senescence as potential drivers of AD risk.
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Asiamah EA, Feng B, Guo R, Yaxing X, Du X, Liu X, Zhang J, Cui H, Ma J. The Contributions of the Endolysosomal Compartment and Autophagy to APOEɛ4 Allele-Mediated Increase in Alzheimer's Disease Risk. J Alzheimers Dis 2024; 97:1007-1031. [PMID: 38306054 DOI: 10.3233/jad-230658] [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] [Indexed: 02/03/2024]
Abstract
Apolipoprotein E4 (APOE4), although yet-to-be fully understood, increases the risk and lowers the age of onset of Alzheimer's disease (AD), which is the major cause of dementia among elderly individuals. The endosome-lysosome and autophagy pathways, which are necessary for homeostasis in both neurons and glia, are dysregulated even in early AD. Nonetheless, the contributory roles of these pathways to developing AD-related pathologies in APOE4 individuals and models are unclear. Therefore, this review summarizes the dysregulations in the endosome-lysosome and autophagy pathways in APOE4 individuals and non-human models, and how these anomalies contribute to developing AD-relevant pathologies. The available literature suggests that APOE4 causes endosomal enlargement, increases endosomal acidification, impairs endosomal recycling, and downregulates exosome production. APOE4 impairs autophagy initiation and inhibits basal autophagy and autophagy flux. APOE4 promotes lysosome formation and trafficking and causes ApoE to accumulate in lysosomes. APOE4-mediated changes in the endosome, autophagosome and lysosome could promote AD-related features including Aβ accumulation, tau hyperphosphorylation, glial dysfunction, lipid dyshomeostasis, and synaptic defects. ApoE4 protein could mediate APOE4-mediated endosome-lysosome-autophagy changes. ApoE4 impairs vesicle recycling and endosome trafficking, impairs the synthesis of autophagy genes, resists being dissociated from its receptors and degradation, and forms a stable folding intermediate that could disrupt lysosome structure. Drugs such as molecular correctors that target ApoE4 molecular structure and enhance autophagy may ameliorate the endosome-lysosome-autophagy-mediated increase in AD risk in APOE4 individuals.
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Affiliation(s)
- Ernest Amponsah Asiamah
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Department of Biomedical Sciences, College of Health and Allied Sciences, University of Cape Coast, PMB UCC, Cape Coast, Ghana
| | - Baofeng Feng
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
- Hebei Technology Innovation Center for Stem Cell and Regenerative Medicine, Hebei, China
| | - Ruiyun Guo
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
| | - Xu Yaxing
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
| | - Xiaofeng Du
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
| | - Xin Liu
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
| | - Jinyu Zhang
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
| | - Huixian Cui
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
- Hebei Technology Innovation Center for Stem Cell and Regenerative Medicine, Hebei, China
| | - Jun Ma
- Hebei Medical University-Galway University of Ireland Stem Cell Research Center, Hebei Medical University, Hebei, China
- Hebei Research Center for Stem Cell Medical Translational Engineering, Hebei, China
- Hebei Technology Innovation Center for Stem Cell and Regenerative Medicine, Hebei, China
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Zhang J, Yang Q, Liu Q, Liu S, Zhu Y, Yao J, Wang H, Guan W. The responses of harmful dinoflagellate Karenia mikimotoi to simulated ocean acidification at the transcriptional level. HARMFUL ALGAE 2022; 111:102167. [PMID: 35016771 DOI: 10.1016/j.hal.2021.102167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 12/06/2021] [Accepted: 12/12/2021] [Indexed: 06/14/2023]
Abstract
The HAB-forming, toxic dinoflagellate Karenia mikimotoi, previously found to benefit from ocean acidification (OA), was cultivated to investigate its transcriptional response to simulated OA for 30 generations. Batch cultures were grown under two CO2 concentrations, 450 (control) and 1100 (simulated OA) μatm, and physiological parameters [growth, pigments, catalase (CAT), glutathione reductase (GR), and superoxide dismutase (SOD) activity], as well as transcriptomes (obtained via RNA-seq), were compared. Chlorophyll a (Chl a) and carotenoid (Caro) contents, as well as CAT and GR activities, were significantly increased under OA conditions. Transcriptomic analysis revealed 2,490 differentially expressed unigenes in response to OA, which comprised 1.54% of all unigenes. A total of 1,121 unigenes were upregulated, and 1,369 unigenes were downregulated in OA compared to control conditions. The downregulated expression of bicarbonate transporter and carbonic anhydrase genes was a landmark of OA acclimation. Key genes involved in energy metabolism, e.g., photosynthesis, tricarboxylic acid cycle, oxidative phosphorylation, and nitrogen metabolism, were highly upregulated under OA, contributing to increases in the Chl a (55.05%) and Caro (28.37%). The enhanced antioxidant enzyme activities (i.e. CAT, GR) and upregulated genes (i.e. glutathione peroxidase, ascorbate peroxidase, heat shock protein, 20S proteasome, aldehyde dehydrogenase, and apolipoprotein) benefit cells against the potential lower pH stress condition under OA. In addition, the downregulation of four genes associated with motility suggested that the preserved energy could further boost growth. In conclusion, the present study suggests that K. mikimotoi exhibits efficient gene expression regulation for the utilization of energy and resistance to OA-induced stress. Taken together, K. mikimotoi appeared as a tolerant species in response to OA. Thus, more extensive algal blooms that threaten marine organisms are likely in the future. These findings expand current knowledge on the gene expression of HAB-forming species in response to future OA.
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Affiliation(s)
- Jiazhu Zhang
- Wenzhou Key Laboratory of Sanitary Microbiology, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Qiongying Yang
- Wenzhou Key Laboratory of Sanitary Microbiology, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Qianlou Liu
- Wenzhou Key Laboratory of Sanitary Microbiology, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Shuqi Liu
- Wenzhou Key Laboratory of Sanitary Microbiology, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Yue Zhu
- Wenzhou Key Laboratory of Sanitary Microbiology, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Jiang Yao
- Wenzhou Key Laboratory of Sanitary Microbiology, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China
| | - Hong Wang
- Department of Medical Laboratory Technology, Xinyang Vocational and Technical College, Xinyang, Henan 464000, China
| | - Wanchun Guan
- Wenzhou Key Laboratory of Sanitary Microbiology, School of Laboratory Medicine and Life Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.
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You M, Zhou X, Yin W, Wan K, Zhang W, Li C, Li M, Zhu W, Zhu X, Sun Z. The Influence of MTHFR Polymorphism on Gray Matter Volume in Patients With Amnestic Mild Cognitive Impairment. Front Neurosci 2021; 15:778123. [PMID: 34916904 PMCID: PMC8670096 DOI: 10.3389/fnins.2021.778123] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 11/05/2021] [Indexed: 12/17/2022] Open
Abstract
The methylenetetrahydrofolate reductase (MTHFR) gene has been associated with Alzheimer's disease (AD) pathogenesis. Amnestic mild cognitive impairment (aMCI) represents a prodromal stage of dementia and involves a high risk of progression into AD. Although the effects of the apolipoprotein E (APOE) gene on structural alterations in aMCI have been widely investigated, the effects of MTHFR C677T and interaction effects of MTHFR × APOE genotypes on gray matter atrophy in aMCI remain largely unknown. In the present study, 60 aMCI patients and 30 healthy controls were enrolled, and voxel-based morphometry analysis was performed to inspect the effects of diagnosis, different genotypes, and their interactions on gray matter atrophy. The results showed that aMCI patients had significant gray matter atrophy involving the bilateral hippocampus, the right parahippocampal gyrus, and the left superior temporal gyrus compared with healthy controls. Besides, a substantial reduction in gray matter volume was observed in the right hippocampus region in APOE ε4 carriers from the aMCI group, compared with APOE ε4 non-carriers. A significant interaction was found between diagnosis and MTHFR C677T genotype on the right precuneus in healthy controls and aMCI patients not carrying APOE ε4 allele. Our findings may provide new evidence substantiating the genetic effects of MTHFR C677T on brain structural alternation in patients with aMCI.
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Affiliation(s)
- Mengzhe You
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Xia Zhou
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Wenwen Yin
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Ke Wan
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Wei Zhang
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Chenchen Li
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Mingxu Li
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Wenhao Zhu
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Xiaoqun Zhu
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zhongwu Sun
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China
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Liou CW, Chen SH, Lin TK, Tsai MH, Chang CC. Oxidative Stress Biomarkers and Mitochondrial DNA Copy Number Associated with APOE4 Allele and Cholinesterase Inhibitor Therapy in Patients with Alzheimer's Disease. Antioxidants (Basel) 2021; 10:antiox10121971. [PMID: 34943074 PMCID: PMC8750673 DOI: 10.3390/antiox10121971] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/02/2021] [Accepted: 12/08/2021] [Indexed: 11/16/2022] Open
Abstract
Studies of the oxidative/anti-oxidative status in patients with Alzheimer’s disease (AD) carrying different alleles of the apolipoprotein E (APOE) gene are currently inconclusive; meanwhile, data regarding mitochondrial DNA copy number (mtCN) remain limited. We herein determined the thiobarbituric acid reactive substances (TBARS), thiols, and mtCN in blood samples of 600 AD patients and 601 controls. A significantly higher oxidative TBARS (1.64 μmol/L), lower antioxidative thiols (1.60 μmol/L), and lower mtCN (2.34 log Delta Ct) were found in the AD cohort as compared to the non-AD cohort (1.54 μmol/L, 1.71 μmol/L, 2.46 log Delta Ct). We further identified the ε4 alleles (APOE4) and separated subjects into three groups according to the number of APOE4. A significant trend was noted in the TBARS levels of both AD and non-AD cohorts, highest in the homozygous two alleles (1.86 and 1.80 μmol/L), followed by heterozygous one allele (1.70 and 1.74 μmol/L), and lowest in the no APOE4 allele (1.56 and 1.48 μmol/L). Similar trends of lower thiols and mtCN were also found in the AD cohort. In our study of the influence of cholinesterase inhibitor therapy, we found significantly reduced TBARS levels, and elevated mtCN in AD patients receiving rivastigmine and galantamine therapy. Our study demonstrates associations between the APOE4 allele and oxidative stress biomarkers and mtCN. Using cholinesterase inhibitor therapy may benefit AD patients through attenuation of oxidative stress and manipulation of the mtCN.
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Affiliation(s)
- Chia-Wei Liou
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (C.-W.L.); (S.-H.C.); (T.-K.L.)
- Center for Mitochondrial Research and Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan
| | - Shih-Hsuan Chen
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (C.-W.L.); (S.-H.C.); (T.-K.L.)
| | - Tsu-Kung Lin
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (C.-W.L.); (S.-H.C.); (T.-K.L.)
- Center for Mitochondrial Research and Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan
| | - Meng-Han Tsai
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (C.-W.L.); (S.-H.C.); (T.-K.L.)
- Correspondence: (M.-H.T.); (C.-C.C.); Tel.: +886-7-7317123 (ext. 2285) (M.-H.T.); +886-7-7318762 (C.-C.C.)
| | - Chiung-Chih Chang
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (C.-W.L.); (S.-H.C.); (T.-K.L.)
- Cognition and Aging Center and Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan
- Correspondence: (M.-H.T.); (C.-C.C.); Tel.: +886-7-7317123 (ext. 2285) (M.-H.T.); +886-7-7318762 (C.-C.C.)
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Walia V, Kaushik D, Mittal V, Kumar K, Verma R, Parashar J, Akter R, Rahman MH, Bhatia S, Al-Harrasi A, Karthika C, Bhattacharya T, Chopra H, Ashraf GM. Delineation of Neuroprotective Effects and Possible Benefits of AntioxidantsTherapy for the Treatment of Alzheimer's Diseases by Targeting Mitochondrial-Derived Reactive Oxygen Species: Bench to Bedside. Mol Neurobiol 2021; 59:657-680. [PMID: 34751889 DOI: 10.1007/s12035-021-02617-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 10/19/2021] [Indexed: 12/25/2022]
Abstract
Alzheimer's disease (AD) is considered the sixth leading cause of death in elderly patients and is characterized by progressive neuronal degeneration and impairment in memory, language, etc. AD is characterized by the deposition of senile plaque, accumulation of fibrils, and neurofibrillary tangles (NFTs) which are responsible for neuronal degeneration. Amyloid-β (Aβ) plays a key role in the process of neuronal degeneration in the case of AD. It has been reported that Aβ is responsible for the production of reactive oxygen species (ROS), depletion of endogenous antioxidants, increase in intracellular Ca2+ which further increases mitochondria dysfunctions, oxidative stress, release of pro-apoptotic factors, neuronal apoptosis, etc. Thus, oxidative stress plays a key role in the pathogenesis of AD. Antioxidants are compounds that have the ability to counteract the oxidative damage conferred by ROS. Therefore, the antioxidant therapy may provide benefits and halt the progress of AD to advance stages by counteracting neuronal degeneration. However, despite the beneficial effects imposed by the antioxidants, the findings from the clinical studies suggested inconsistent results which might be due to poor study design, selection of the wrong antioxidant, inability of the molecule to cross the blood-brain barrier (BBB), treatment in the advanced state of disease, etc. The present review insights into the neuroprotective effects and limitations of the antioxidant therapy for the treatment of AD by targeting mitochondrial-derived ROS. This particular article will certainly help the researchers to search new avenues for the treatment of AD by utilizing mitochondrial-derived ROS-targeted antioxidant therapies.
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Affiliation(s)
- Vaibhav Walia
- SGT College of Pharmacy, SGT University, Gurugram, Haryana, India
| | - Deepak Kaushik
- Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak, 124001, India
| | - Vineet Mittal
- Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak, 124001, India
| | - Kuldeep Kumar
- Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, Punjab, India
- University Institute of Pharmaceutical Sciences (UIPS), Chandigarh University, Gharuan, Mohali, Punjab, India
| | - Ravinder Verma
- Department of Pharmacy, School of Medical and Allied Sciences, G.D. Goenka University, Gurugram, 122103, India
| | - Jatin Parashar
- Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak, 124001, India
| | - Rokeya Akter
- Department of Pharmacy, Jagannath University, Sadarghat, Dhaka, 1100, Bangladesh
| | - Md Habibur Rahman
- Department of Pharmacy, Southeast University, Banani, Dhaka, 1213, Bangladesh.
| | - Saurabh Bhatia
- School of Health Science University of Petroleum and Energy Studies, Dehrandun, Uttarkhand, 248007, India
- Natural & Medical Sciences Research Center, University of Nizwa, 616 Birkat Al Mouz, P.O. Box 33, Nizwa, Oman
| | - Ahmed Al-Harrasi
- Natural & Medical Sciences Research Center, University of Nizwa, 616 Birkat Al Mouz, P.O. Box 33, Nizwa, Oman
| | - Chenmala Karthika
- Department of Pharmaceutics, JSS College of Pharmacy, JSS Academy of Higher Education & Research, The Nilgiris, Ooty, 643001, Tamil Nadu, India
| | - Tanima Bhattacharya
- College of Chemistry & Chemical Engineering, Hubei University, Wuhan, 430062, China
| | - Hitesh Chopra
- Chitkara College of Pharmacy, Chitkara University, Punjab, 140401, India
| | - Ghulam Md Ashraf
- Pre-Clinical Research Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
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Lee YG, Park M, Jeong SH, Kang SW, Baik K, Jung JH, Lee PH, Sohn YH, Ye BS. Effects of baseline serum uric acid and apolipoprotein E4 on longitudinal cognition and cerebral metabolism. Neurobiol Aging 2021; 106:223-231. [PMID: 34311431 DOI: 10.1016/j.neurobiolaging.2021.05.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 04/28/2021] [Accepted: 05/03/2021] [Indexed: 12/20/2022]
Abstract
Serum uric acid, a natural antioxidant, may have a protective effect on the progression of Alzheimer's disease (AD). To investigate the effect of serum uric acid on longitudinal cognitive and brain metabolic changes, we utilized data on baseline serum uric acid levels, APOE genotyping, and longitudinal cognitive scores from the Alzheimer's Disease Neuroimaging Initiative for 1,343 participants with normal cognition (NC), mild cognitive impairment (MCI), or dementia. In 979 participants, brain metabolism was measured using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) images. Higher serum uric acid levels exhibited a detrimental effect on NC, whereas a protective trend was observed in individuals with cognitive impairment. Interestingly, higher uric acid levels were associated with a slower decline in cognitive scores and brain metabolism in females with MCI, and this effect was found in APOE4 carriers, but not in non-carriers. Longitudinal AD-like patterns of brain metabolism on FDG-PET images also appeared to mediate the effects of baseline uric acid levels on longitudinal cognitive decline. In summary, higher serum uric acid may interact with APOE4 to alleviate longitudinal metabolic changes and cognitive decline in female MCI patients.
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Affiliation(s)
- Young-Gun Lee
- Department of Neurology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Mincheol Park
- Department of Neurology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Seong Ho Jeong
- Department of Neurology, Sanggye Paik Hospital, Inje University College of Medicine, Seoul, South Korea
| | - Sung Woo Kang
- Department of Neurology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Kyoungwon Baik
- Department of Neurology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jin Ho Jung
- Department of Neurology, Inje University Busan Paik Hospital, Busan, Republic of Korea
| | - Phil Hyu Lee
- Department of Neurology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Young Ho Sohn
- Department of Neurology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Byoung Seok Ye
- Department of Neurology, Yonsei University College of Medicine, Seoul, Republic of Korea.
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Fote GM, Geller NR, Reyes-Ortiz AM, Thompson LM, Steffan JS, Grill JD. A Scoping Review of Dietary Factors Conferring Risk or Protection for Cognitive Decline in APOE ε4 Carriers. J Nutr Health Aging 2021; 25:1167-1178. [PMID: 34866144 PMCID: PMC8890439 DOI: 10.1007/s12603-021-1705-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Alzheimer's disease (AD) is a progressive and fatal neurodegenerative disease. The strongest genetic risk factor for sporadic AD is carriage of the ε4 allele of the Apolipoprotein E (APOE) gene. Strategies to slow the progression of AD, including dietary interventions, may be modified by the pathogenic effect of this polymorphism. Our objective in this review was to determine the extent and quality of the literature investigating how dietary factors and interventions interact with the APOE ε4 genotype to impact cognitive decline in AD. To that end, we performed a systematic scoping review of published English-language articles involving human subjects. We found evidence suggesting that adherence to a Mediterranean diet may reduce cognitive decline among APOE ε4 carriers, whereas ketogenic agents appear to be ineffective. Diets high in saturated fats may be particularly harmful for APOE ε4 carriers. We identified several topics, including the use of ω-3 fatty acid and antioxidant supplements, for which additional high level evidence is needed.
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Affiliation(s)
- G M Fote
- Gianna M. Fote, PhD, UC Irvine Department of Biological Chemistry, 385 S. Manchester Ave, Unit 2096, Orange CA 92868, USA, (310)924-4415, ; Joshua D. Grill, PhD, UC Irvine Institute for Memory Impairments and Neurological Disorders, Professor of Psychiatry and Human Behavior, Professor of Neurobiology and Behavior, University of California, Irvine, 3024 Biological Sciences III, Irvine, CA 92697, USA,
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Cancer Chemotherapy Related Cognitive Impairment and the Impact of the Alzheimer's Disease Risk Factor APOE. Cancers (Basel) 2020; 12:cancers12123842. [PMID: 33352780 PMCID: PMC7766535 DOI: 10.3390/cancers12123842] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 12/16/2020] [Accepted: 12/16/2020] [Indexed: 12/16/2022] Open
Abstract
Cancer related cognitive impairment (CRCI) is a serious impairment to maintaining quality of life in cancer survivors. Cancer chemotherapy contributes to this condition through several potential mechanisms, including damage to the blood brain barrier, increases in oxidative stress and inflammation in the brain, and impaired neurogenesis, each of which lead to neuronal dysfunction. A genetic predisposition to CRCI is the E4 allele of the Apolipoprotein E gene (APOE), which is also the strongest genetic risk factor for Alzheimer's disease. In normal brains, APOE performs essential lipid transport functions. The APOE4 isoform has been linked to altered lipid binding, increased oxidative stress and inflammation, reduced turnover of neural progenitor cells, and impairment of the blood brain barrier. As chemotherapy also affects these processes, the influence of APOE4 on CRCI takes on great significance. This review outlines the main areas where APOE genotype could play a role in CRCI. Potential therapeutics based on APOE biology could mitigate these detrimental cognitive effects for those receiving chemotherapy, emphasizing that the APOE genotype could help in developing personalized cancer treatment regimens.
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Cioffi F, Adam RHI, Broersen K. Molecular Mechanisms and Genetics of Oxidative Stress in Alzheimer's Disease. J Alzheimers Dis 2020; 72:981-1017. [PMID: 31744008 PMCID: PMC6971833 DOI: 10.3233/jad-190863] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Alzheimer’s disease is the most common neurodegenerative disorder that can cause dementia in elderly over 60 years of age. One of the disease hallmarks is oxidative stress which interconnects with other processes such as amyloid-β deposition, tau hyperphosphorylation, and tangle formation. This review discusses current thoughts on molecular mechanisms that may relate oxidative stress to Alzheimer’s disease and identifies genetic factors observed from in vitro, in vivo, and clinical studies that may be associated with Alzheimer’s disease-related oxidative stress.
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Affiliation(s)
- Federica Cioffi
- Nanobiophysics Group, Technical Medical Centre, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Rayan Hassan Ibrahim Adam
- Nanobiophysics Group, Technical Medical Centre, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Kerensa Broersen
- Applied Stem Cell Technologies, Technical Medical Centre, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
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11
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Erythrocytes as markers of oxidative stress related pathologies. Mech Ageing Dev 2020; 191:111333. [PMID: 32814082 DOI: 10.1016/j.mad.2020.111333] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 07/20/2020] [Accepted: 07/21/2020] [Indexed: 02/06/2023]
Abstract
Erythrocytes are deeply sensitive cells and important health indicators. During inflammatory response RBC, as a part of haematological system, are exposed to circulating inflammatory mediators and related oxidative stress. They present a highly specialized and organized cell membrane that interacts with inflammatory mediators and oxidative agents, leading to a variety of structural changes that promptly signal an abnormal situation. This review is aimed to provide an overview on erythrocyte involvement in physiological and pathological processes related to oxidative stress, such as aging, Down syndrome, neurodegenerative diseases, for instance Alzheimer Disease, erectile dysfunction and cardiovascular diseases. In particular this review will focus on the effects of oxidative stress on structural changes in the cell membrane and also on in the activity of erythrocyte enzymes such as membrane-bound, cytosolic glycohydrolases and RBC-eNOS. This review also underlines the potential clinical application of erythrocyte specific related parameters, which can be important tools not only for the study but also for the monitoring of several oxidative stress related diseases.
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12
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Johnson LA. APOE and metabolic dysfunction in Alzheimer's disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2020; 154:131-151. [PMID: 32739002 DOI: 10.1016/bs.irn.2020.02.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The strongest genetic risk factor for sporadic Alzheimer's disease (AD) is carriage of the E4 allele of APOE. Metabolic dysfunction also increases risk of dementia and AD. Facing a need for effective therapies and an aging global population, studies aimed at uncovering new therapeutic targets for AD have become critical. Insight into the biology underlying the effects of E4 and metabolic impairment on the brain may lead to novel therapies to reduce AD risk. An understudied hallmark of both AD patients and E4 individuals is a common metabolic impairment-cerebral glucose hypometabolism. This is a robust and replicated finding in humans, and begins decades prior to cognitive decline. Possession of E4 also appears to alter several other aspects of cerebral glucose metabolism, fatty acid metabolism, and management of oxidative stress through the pentose phosphate pathway. A critical knowledge gap in AD is the mechanism by which APOE alters cerebral metabolism and clarification as to its relevance to AD risk. Facing a need for effective therapies, studies aimed at uncovering new therapeutic targets have become critical. One such approach is to gain a better understanding of the metabolic mechanisms that may underlie E4-associated cognitive dysfunction and AD risk.
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Affiliation(s)
- Lance A Johnson
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, United States; Sanders-Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, United States.
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13
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Ertuzun T, Semerci A, Cakir ME, Ekmekcioglu A, Gok MO, Soltys DT, de Souza-Pinto NC, Sezerman U, Muftuoglu M. Investigation of base excision repair gene variants in late-onset Alzheimer's disease. PLoS One 2019; 14:e0221362. [PMID: 31415677 PMCID: PMC6695184 DOI: 10.1371/journal.pone.0221362] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 08/05/2019] [Indexed: 12/03/2022] Open
Abstract
Base excision repair (BER) defects and concomitant oxidative DNA damage accumulation play a role in the etiology and progression of late-onset Alzheimer’s disease (LOAD). However, it is not known whether genetic variant(s) of specific BER genes contribute to reduced BER activity in LOAD patients and whether they are associated with risk, development and/or progression of LOAD. Therefore, we performed targeted next generation sequencing for three BER genes, uracil glycosylase (UNG), endonuclease VIII-like DNA glycosylase 1 (NEIL1) and polymerase β (POLβ) including promoter, exonic and intronic regions in peripheral blood samples and postmortem brain tissues (temporal cortex, TC and cerebellum, CE) from LOAD patients, high-pathology control and cognitively normal age-matched controls. In addition, the known LOAD risk factor, APOE was included in this study to test whether any BER gene variants associate with APOE variants, particularly APOE ε4. We show that UNG carry five significant variants (rs1610925, rs2268406, rs80001089, rs1018782 and rs1018783) in blood samples of Turkish LOAD patients compared to age-matched controls and one of them (UNG rs80001089) is also significant in TC from Brazilian LOAD patients (p<0.05). The significant variants present only in CE and TC from LOAD are UNG rs2569987 and POLβ rs1012381950, respectively. There is also significant epistatic relationship (p = 0.0410) between UNG rs80001089 and NEIL1 rs7182283 in TC from LOAD subjects. Our results suggest that significant BER gene variants may be associated with the risk of LOAD in non-APOE ε4 carriers. On the other hand, there are no significant UNG, NEIL1 and POLβ variants that could affect their protein level and function, suggesting that there may be other factors such as post-transcriptional or–translational modifications responsible for the reduced activities and protein levels of these genes in LOAD pathogenesis. Further studies with increased sample size are needed to confirm the relationship between BER variants and LOAD risk.
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Affiliation(s)
- Tugce Ertuzun
- Department of Molecular Biology and Genetics
- Department of Medical Biotechnology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Asli Semerci
- Department of Medical Biotechnology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Mehmet Emin Cakir
- Department of Neurology, Medeniyet University, Goztepe Training and Research Hospital, Istanbul, Turkey
| | - Aysegul Ekmekcioglu
- Department of Medical Biotechnology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Mehmet Oguz Gok
- Department of Medical Biotechnology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Daniela T. Soltys
- Departmento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Nadja C. de Souza-Pinto
- Departmento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Ugur Sezerman
- Department of Biostatistics and Medical Informatics, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Meltem Muftuoglu
- Department of Molecular Biology and Genetics
- Department of Medical Biotechnology, Acibadem Mehmet Ali Aydinlar University, Istanbul, Turkey
- * E-mail:
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14
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Massaccesi L, Galliera E, Galimberti D, Fenoglio C, Arcaro M, Goi G, Barassi A, Corsi Romanelli MM. Lag-time in Alzheimer's disease patients: a potential plasmatic oxidative stress marker associated with ApoE4 isoform. IMMUNITY & AGEING 2019; 16:7. [PMID: 30984280 PMCID: PMC6444862 DOI: 10.1186/s12979-019-0147-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 03/14/2019] [Indexed: 12/16/2022]
Abstract
In the brain, Oxidative Stress (OS) contribute to structural and functional changes associated with vascular aging, such as endothelial dysfunction, extracellular matrix degradation, resulting in age-related reduced vasodilatation in response to agonists. For this reason, OS is considered a key factor in Alzheimer’s Disease (AD) development and recent evidence correlated oxidative stress with vascular lesion in the pathogenesis of AD, but the mechanism still need to be fully clarified. The etiology of AD is still not completely understood and is influenced by several factors including Apolipoprotein E (ApoE) genotype. In particular, the Apo ε4 isoform is considered a risk factor for AD development. This study was aimed to evaluate the possible relationship between three plasmatic OS marker and Apo ε4 carrier status. Plasmatic soluble receptor for advanced glycation end products (sRAGE) levels, plasma antioxidant total defenses (by lag-time method) and plasmatic Reactive Oxygen species (ROS) levels were evaluated in 25 AD patients and in 30 matched controls. ROS were significantly higher while plasma antioxidant total defenses and sRAGE levels were significantly lower in AD patients compared to controls. In AD patients lag-time values show a significant positive linear correlation with sRAGE levels and a (even not significant) negative correlation with ROS levels. Lag-time is significantly lower in ε4 carrier (N = 13) than in ε4 non-carrier (N = 12). Our result confirms the substantial OS in AD. Lag-time levels showed a significant positive correlation with sRAGE levels and a significant association with ε4 carrier status suggesting that plasmatic lag-time evaluation can be considered as a potential useful OS risk marker in AD.
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Affiliation(s)
- Luca Massaccesi
- 1Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy
| | - Emanuela Galliera
- 1Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy.,2IRCCS Galeazzi Orthopaedic Institute, Milan, Italy
| | - Daniela Galimberti
- 3Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Centro "Dino Ferrari", Milan, Italy.,4U.O.S.D. Neurologia-Malattie Neurodegenerative, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Chiara Fenoglio
- 3Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Centro "Dino Ferrari", Milan, Italy.,4U.O.S.D. Neurologia-Malattie Neurodegenerative, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Marina Arcaro
- 4U.O.S.D. Neurologia-Malattie Neurodegenerative, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Giancarlo Goi
- 5Department of Biomedical, Surgical and Dental Sciences, Università degli Studi di Milano, Milan, Italy
| | - Alessandra Barassi
- 6Department of Health's Science, Università degli Studi di Milano, Milan, Italy
| | - Massimiliano Marco Corsi Romanelli
- 1Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy.,7U.O.C SMEL-1 Patologia Clinica IRCCS Policlinico San Donato, San Donato, Milan, Italy
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15
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Persson T, Lattanzio F, Calvo-Garrido J, Rimondini R, Rubio-Rodrigo M, Sundström E, Maioli S, Sandebring-Matton A, Cedazo-Mínguez Á. Apolipoprotein E4 Elicits Lysosomal Cathepsin D Release, Decreased Thioredoxin-1 Levels, and Apoptosis. J Alzheimers Dis 2018; 56:601-617. [PMID: 28035917 PMCID: PMC5271484 DOI: 10.3233/jad-150738] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The major genetic risk factor for Alzheimer’s disease (AD), apolipoprotein E4 (ApoE4), has been suggested to have detrimental effects on neurons, including direct toxicity via apoptosis. Thioredoxin-1 (Trx1) is an endogenous antioxidant protein important for redox regulation and participates in the regulation of apoptosis through the inhibition of apoptosis signal-regulating kinase-1 (Ask-1). In this study, we have investigated the effects of ApoE on Trx1 in the brain. Our results showed that the protein levels of Trx1 were reduced in the hippocampus of ApoE4 targeted replacement (TR) mice compared to ApoE3 TR mice. The reduction was also seen in vitro after treatment of both human primary cortical neurons and neuroblastoma cells with human recombinant ApoE4 (rApoE4). Furthermore, ApoE4 caused a disruption of lysosomal integrity and a shift in the localization of Cathepsin D, an enzyme known to degrade Trx1. ApoE4 treatment induced in addition apoptosis through translocation of Death-domain associated protein-6 (Daxx) from the nucleus to the cytosol, suggesting an activation of the Ask-1 pathway. This toxicity was prevented by overexpression of Trx1 and other endogenous Ask-1 inhibitors. Our data suggests that down-regulation of Trx1 is involved in the toxicity caused by ApoE4. An activated ASK-1 pathway might indeed make cells more vulnerable to other insults such as amyloid-β, which could partially explain the mechanism behind the strongest genetic risk factor for AD.
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Affiliation(s)
- Torbjörn Persson
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - Francesca Lattanzio
- Department of Pharmacy and Biotechnologies, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Javier Calvo-Garrido
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - Roberto Rimondini
- Department-DIMEC-University of Bologna, Medical and Surgical Science, Bologna, Italy
| | - Marta Rubio-Rodrigo
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - Erik Sundström
- Department of Pharmacy and Biotechnologies, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Silvia Maioli
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - Anna Sandebring-Matton
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - Ángel Cedazo-Mínguez
- Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
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16
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López-Riquelme N, Alom-Poveda J, Viciano-Morote N, Llinares-Ibor I, Tormo-Díaz C. Apolipoprotein E ε4 allele and malondialdehyde level are independent risk factors for Alzheimer's disease. SAGE Open Med 2016; 4:2050312115626731. [PMID: 26835020 PMCID: PMC4729229 DOI: 10.1177/2050312115626731] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 12/18/2015] [Indexed: 11/15/2022] Open
Abstract
Background: The ε4 allele of Apolipoprotein E is involved in lipid metabolism. Oxidative stress produces an increase in lipid peroxidation that has been implicated in the pathogenic cascade in Alzheimer’s disease. This study estimated the effect of the ε4 allele, malondialdehyde and lipid levels on the risk for Alzheimer’s disease. Methods: A total of 41 control subjects and 73 patients with Alzheimer’s disease were recruited. The Apolipoprotein E genotype was determined by amplification of exon 4 of the Apolipoprotein E by polymerase chain reaction (PCR); malondialdehyde concentration was determined by high-pressure liquid chromatography, and serum lipids were measured by routine photometric techniques. Results: Malondialdehyde levels were significantly higher in Alzheimer’s disease patients independent of the Apolipoprotein E genotype and ε4 allele. The ε4 allele increases the risk of Alzheimer’s disease by 5.114 times and elevated malondialdehyde levels increase the risk by 9.342. Conclusion: The presence of ε4 allele and elevated malondialdehyde levels are independent risk factors for Alzheimer’s disease. These findings support the hypothesis that lipid peroxidation and ε4 allele contribute to the pathogenic cascade in Alzheimer’s disease by different pathways.
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Affiliation(s)
| | - Jordi Alom-Poveda
- Neurology Department, General University Hospital of Elche, Elche, Spain; Center for Biomedical Research in Neurodegenerative Diseases Network (CIBERNED), Madrid, Spain
| | - Nuria Viciano-Morote
- Clinical Laboratory Department, General University Hospital of Elche, Elche, Spain
| | | | - Consuelo Tormo-Díaz
- Clinical Laboratory Department, General University Hospital of Elche, Elche, Spain
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17
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Vagelatos NT, Eslick GD. Type 2 diabetes as a risk factor for Alzheimer's disease: the confounders, interactions, and neuropathology associated with this relationship. Epidemiol Rev 2013; 35:152-60. [PMID: 23314404 DOI: 10.1093/epirev/mxs012] [Citation(s) in RCA: 237] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/21/2013] [Indexed: 12/24/2022] Open
Abstract
We performed a systematic review and meta-analysis to explore whether type 2 diabetes mellitus (T2DM) increases the risk of Alzheimer's disease (AD). We also reviewed interactions with smoking, hypertension, and apolipoprotein E ɛ4. Using a series of databases (MEDLINE, EMBASE, PubMed, Current Contents Connect, and Google Scholar), we identified a total of 15 epidemiologic studies. Fourteen studies reported positive associations, of which 9 were statistically significant. Risk estimates ranged from 0.83 to 2.45. The pooled adjusted risk ratio was 1.57 (95% confidence interval: 1.41, 1.75), with a population-attributable risk of 8%. Smoking and hypertension, when comorbid with T2DM, had odds of 14 and 3, respectively. Of the 5 studies that investigated the interaction between T2DM and apolipoprotein E ɛ4, 4 showed positive associations, of which 3 were significant, with odds ranging from 2.4 to 4.99. The pooled adjusted risk ratio was 2.91 (95% confidence interval: 1.51, 5.61). Risk estimates were presented in the context of a key confounder-cerebral infarcts-which are more common in those with T2DM and might contribute to the manifestation of clinical AD. We provide evidence from clinico-neuropathologic studies that demonstrates the following: First, cerebral infarcts are more common than AD-type pathology in those with T2DM and dementia. Second, those with dementia at postmortem are more likely to have both AD-type and cerebrovascular pathologies. Finally, cerebral infarcts reduce the number of AD lesions required for the manifestation of clinical dementia, but they do not appear to interact synergistically with AD-type pathology. Therefore, the increased risk of clinically diagnosed AD seems to be mediated through cerebrovascular pathology.
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18
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Eskici G, Axelsen PH. Copper and Oxidative Stress in the Pathogenesis of Alzheimer’s Disease. Biochemistry 2012; 51:6289-311. [DOI: 10.1021/bi3006169] [Citation(s) in RCA: 204] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Gözde Eskici
- Departments of Pharmacology, Biochemistry and Biophysics,
and Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania 19104, United
States
| | - Paul H. Axelsen
- Departments of Pharmacology, Biochemistry and Biophysics,
and Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania 19104, United
States
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19
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Tamaoka A. [108th Scientific Meeting of the Japanese Society of Internal Medicine: symposium: 1. Progress in dementia research--dementia disorders and protein; (2) amyloid P3 protein]. NIHON NAIKA GAKKAI ZASSHI. THE JOURNAL OF THE JAPANESE SOCIETY OF INTERNAL MEDICINE 2011; 100:2469-2475. [PMID: 22117336 DOI: 10.2169/naika.100.2469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Affiliation(s)
- Akira Tamaoka
- Department of Neurology, Graduate School of Comprehensive Human Sciences Majors of Medical Sciences, University of Tsukuba, Japan
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20
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Axelsen PH, Komatsu H, Murray IVJ. Oxidative stress and cell membranes in the pathogenesis of Alzheimer's disease. Physiology (Bethesda) 2011; 26:54-69. [PMID: 21357903 DOI: 10.1152/physiol.00024.2010] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Amyloid β proteins and oxidative stress are believed to have central roles in the development of Alzheimer's disease. Lipid membranes are among the most vulnerable cellular components to oxidative stress, and membranes in susceptible regions of the brain are compositionally distinct from those in other tissues. This review considers the evidence that membranes are either a source of neurotoxic lipid oxidation products or the target of pathogenic processes involving amyloid β proteins that cause permeability changes or ion channel formation. Progress toward a comprehensive theory of Alzheimer's disease pathogenesis is discussed in which lipid membranes assume both roles and promote the conversion of monomeric amyloid β proteins into fibrils, the pathognomonic histopathological lesion of the disease.
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Affiliation(s)
- Paul H Axelsen
- Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
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21
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Hydrogen sulfide antagonizes homocysteine-induced neurotoxicity in PC12 cells. Neurosci Res 2010; 68:241-9. [DOI: 10.1016/j.neures.2010.07.2039] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Revised: 06/02/2010] [Accepted: 07/21/2010] [Indexed: 01/15/2023]
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22
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Lehmann DJ, Schuur M, Warden DR, Hammond N, Belbin O, Kölsch H, Lehmann MG, Wilcock GK, Brown K, Kehoe PG, Morris CM, Barker R, Coto E, Alvarez V, Deloukas P, Mateo I, Gwilliam R, Combarros O, Arias-Vásquez A, Aulchenko YS, Ikram MA, Breteler MM, van Duijn CM, Oulhaj A, Heun R, Cortina-Borja M, Morgan K, Robson K, Smith AD. Transferrin and HFE genes interact in Alzheimer's disease risk: the Epistasis Project. Neurobiol Aging 2010; 33:202.e1-13. [PMID: 20817350 DOI: 10.1016/j.neurobiolaging.2010.07.018] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2010] [Revised: 07/09/2010] [Accepted: 07/19/2010] [Indexed: 12/01/2022]
Abstract
Iron overload may contribute to the risk of Alzheimer's disease (AD). In the Epistasis Project, with 1757 cases of AD and 6295 controls, we studied 4 variants in 2 genes of iron metabolism: hemochromatosis (HFE) C282Y and H63D, and transferrin (TF) C2 and -2G/A. We replicated the reported interaction between HFE 282Y and TF C2 in the risk of AD: synergy factor, 1.75 (95% confidence interval, 1.1-2.8, p = 0.02) in Northern Europeans. The synergy factor was 3.1 (1.4-6.9; 0.007) in subjects with the APOEε4 allele. We found another interaction, between HFE 63HH and TF -2AA, markedly modified by age. Both interactions were found mainly or only in Northern Europeans. The interaction between HFE 282Y and TF C2 has now been replicated twice, in altogether 2313 cases of AD and 7065 controls, and has also been associated with increased iron load. We therefore suggest that iron overload may be a causative factor in the development of AD. Treatment for iron overload might thus be protective in some cases.
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Affiliation(s)
- Donald J Lehmann
- Oxford Project to Investigate Memory and Ageing, University Department of Physiology, Anatomy and Genetics, Oxford, UK.
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23
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Bednarska- Makaruk M, Rodo M, Graban A, Łojkowska W, Bochyńska A, Ryglewicz D, Wehr H. Antibodies against oxidized LDL and apolipoprotein E polymorphism in demented patients. J Neurol Sci 2009; 283:137-8. [DOI: 10.1016/j.jns.2009.02.345] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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24
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Carmel JF, Tarnus E, Cohn JS, Bourdon E, Davignon J, Bernier L. High expression of apolipoprotein E impairs lipid storage and promotes cell proliferation in human adipocytes. J Cell Biochem 2009; 106:608-17. [PMID: 19130493 DOI: 10.1002/jcb.22037] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Apolipoprotein E (apoE), a key regulator of lipid metabolism, is highly produced by adipose tissue and adipocytes. However, there is little information about its role on adipocyte functions. Because apoE-deficiency in adipocytes was shown to impair adipocyte differentiation, we investigated the consequences of apoE high expression on differentiation and proliferation of a human adipocytic cell line (SW872). SW872 cells were transfected with human apoE to induce a fivefold increase in apoE production and secretion. Adipocyte differentiation and proliferation were assayed by measuring lipid content, adipogenic gene expression, cell number, cell resistance to serum deprivation, and cell division kinetics. Cultured apoE-transfected cells accumulated less triglycerides and less cholesterol than control cells. This decrease in lipid accumulation was associated with a strong downregulation of peroxisome proliferator-activated receptors gamma1 and gamma2 and stearoyl-CoA desaturase 1. The decrease in lipid accumulation was not dependent on the presence of lipids, lipoproteins, or PPAR-gamma agonists in the culture medium, nor was it observed with exogenously added apoE. Moreover, we observed that apoE-transfected cells were more resistant to death induced by serum deprivation, and that these cells underwent more cell divisions than control cells. These results bring new evidence of apoE-involvement in metabolic disorders at the adipocyte level.
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Affiliation(s)
- Jean-François Carmel
- Hyperlipidemia and Atherosclerosis Research Group, Clinical Research Institute of Montreal, Montreal, Quebec, Canada
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25
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Guan J, Zhao HL, Baum L, Sui Y, He L, Wong H, Lai FMM, Tong PCY, Chan JCN. Apolipoprotein E polymorphism and expression in type 2 diabetic patients with nephropathy: clinicopathological correlation. Nephrol Dial Transplant 2009; 24:1889-95. [PMID: 19218599 DOI: 10.1093/ndt/gfn734] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Diabetic nephropathy represents a heterogeneous group of renal pathologies that may be associated with genetic susceptibility. There have been clinical reports on the risk association of diabetic nephropathy with an apolipoprotein E (ApoE) exon 4 polymorphism although its correlations with renal histopathological changes have not been explored. METHODS A total of 213 adult autopsies with type 2 diabetes and 111 non-diabetic control cases were analysed. Genomic DNA samples were obtained from spleen tissues. The ApoE genotype was determined by PCR-LDR analysis. Histopathological examination of kidney sections was performed in a subset of 51 diabetic and 111 control cases. ApoE protein expression in diabetic carriers with similar clinical status was examined by immunohistochemical staining. RESULTS In type 2 diabetes, epsilon2 carriers (P = 0.04; odds ratio = 5.42; 95% CI: 1.10-26.8) and epsilon3/epsilon4 (P = 0.04; odds ratio = 22.5; 95% CI: 1.11-454.90) genotype carriers were more likely to have glomerular hypertrophy than were epsilon3/epsilon3 carriers. The epsilon2 carriers showed an increase in glomerular ApoE protein expression. A correlation between ApoE genotype and nodular glomerulosclerosis was not found. CONCLUSIONS Our findings confirm the risk association of the ApoE polymorphism with diabetic nephropathy in clinical studies and is the first study demonstrating the correlations between ApoE genotypes, protein expression and structural changes in diabetic nephropathy.
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Affiliation(s)
- Jing Guan
- Department of Medicine and Therapeutics, The Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
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26
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Su B, Wang X, Nunomura A, Moreira PI, Lee HG, Perry G, Smith MA, Zhu X. Oxidative stress signaling in Alzheimer's disease. Curr Alzheimer Res 2009; 5:525-32. [PMID: 19075578 DOI: 10.2174/156720508786898451] [Citation(s) in RCA: 199] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Multiple lines of evidence demonstrate that oxidative stress is an early event in Alzheimer's disease (AD), occurring prior to cytopathology, and therefore may play a key pathogenic role in AD. Oxidative stress not only temporally precedes the pathological lesions of the disease but also activates cell signaling pathways, which, in turn, contribute to lesion formation and, at the same time, provoke cellular responses such as compensatory upregulation of antioxidant enzymes found in vulnerable neurons in AD. In this review, we provide an overview of the evidence of oxidative stress and compensatory responses that occur in AD, particularly focused on potential sources of oxidative stress and the roles and mechanism of activation of stress-activated protein kinase pathways.
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Affiliation(s)
- B Su
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Jofre-Monseny L, Minihane AM, Rimbach G. Impact of apoE genotype on oxidative stress, inflammation and disease risk. Mol Nutr Food Res 2008; 52:131-45. [PMID: 18203129 DOI: 10.1002/mnfr.200700322] [Citation(s) in RCA: 225] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Although in developing countries an apolipoprotein E4 (apoE4) genotype may offer an evolutionary advantage, as it has been shown to offer protection against certain infectious disease, in Westernised societies it is associated with increased morbidity and mortality, and represents a significant risk factor for cardiovascular disease, late-onset Alzheimer's disease and other chronic disorders. ApoE is an important modulator of many stages of lipoprotein metabolism and traditionally the increased risk was attributed to higher lipid levels in E4 carriers. However, more recent evidence demonstrates the multifunctional nature of the apoE protein and the fact that the impact of genotype on disease risk may be in large part due to an impact on oxidative status or the immunomodulatory/anti-inflammatory properties of apoE. An increasing number of studies in cell lines, targeted replacement rodents and human volunteers indicate higher oxidative stress and a more pro-inflammatory state associated with the epsilon4 allele. The impact of genotype on the antioxidant and immunomodulatory/anti-inflammatory properties of apoE is the focus of the current review. Furthermore, current information on the impact of environment (diet, exercise, smoking status, alcohol) on apoE genotype-phenotype associations are discussed with a view to identifying particular lifestyle strategies that could be adapted to counteract the 'at-risk' E4 genotype.
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Affiliation(s)
- Laia Jofre-Monseny
- Institute of Human Nutrition and Food Science, Christian Albrechts University of Kiel, Kiel, Germany
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28
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Jofre-Monseny L, de Pascual-Teresa S, Plonka E, Huebbe P, Boesch-Saadatmandi C, Minihane AM, Rimbach G. Differential effects of apolipoprotein E3 and E4 on markers of oxidative status in macrophages. Br J Nutr 2007; 97:864-71. [PMID: 17381973 DOI: 10.1017/s0007114507669219] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
ApoE is secreted by macrophages at the lesion site of the atherosclerotic plaque, where it is thought to play a protective role against atherosclerosis independently of its effects on lipid metabolism. Of the three common isoforms for apoE, apoE4 is associated with higher risk of cardiovascular disease (CVD). In vitro studies have shown that recombinant apoE may act as an antioxidant in an isoform-dependent manner (E2 > E3 > E4). The oxidative status of the macrophages plays a key role in the process of atherosclerosis. In the present study the possible differential actions of apoE3 and apoE4 on several parameters of oxidative status were determined in stably transfected murine macrophages (RAW 264-7-apoE3 and - apoE4). No differences between genotypes were observed after peroxide challenge in either protection against cytotoxicity or in cell membrane oxidation, and modest differences were observed in the non-enzymatic antioxidants (glutathione and alpha-tocopherol) in apoE3 v. apoE4 macrophages. Importantly, cells secreting apoE4 showed increased membrane oxidation under basal conditions, and produced more NO and superoxide anion radicals than the apoE3 macrophages after stimulation. The present data suggest that apoE genotype influences the oxidative status of macrophages, and this could partly contribute to the higher CVD risk observed in apoE4 carriers.
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Affiliation(s)
- Laia Jofre-Monseny
- Institute of Human Nutrition and Food Science, Christian Albrechts University of Kiel, Hermann-Rodewald-Strasse 6, 24098 Kiel, Germany
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Ancelin ML, Christen Y, Ritchie K. Is antioxidant therapy a viable alternative for mild cognitive impairment? Examination of the evidence. Dement Geriatr Cogn Disord 2007; 24:1-19. [PMID: 17495472 DOI: 10.1159/000102567] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/18/2007] [Indexed: 12/14/2022] Open
Abstract
Therapeutic interventions for the prodromal stages of dementia are currently being sought with a view to delaying if not preventing disease onset. Uncertainty as to whether cognitive disorder in a given individual will progress towards dementia and adverse drug side effects has led to hesitancy on the part of drug regulators to instigate preventive pharmacotherapies. In this context, antioxidant therapies may provide a low-risk alternative, targeting very early biological changes. While a growing body of knowledge demonstrates both the importance of oxidative stress in the aetiology of dementia and the efficacy of antioxidant treatment in animal and cellular models, studies in humans are presently inconclusive. While some antioxidants, notably flavonoid- or vitamin-rich diets, appear to lower the relative risk for Alzheimer's disease in humans in observational studies, these results must be interpreted in the light of the biological complexity of the relationship between oxidative stress and neurodegeneration, and the methodological and theoretical shortcomings of studies conducted to date. A clearer understanding of these factors will assist in the interpretation of the results of the intervention studies which are now being undertaken; these studies being the only current means of establishing efficacy for preventive drug treatment of Alzheimer's disease.
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Minihane AM, Jofre-Monseny L, Olano-Martin E, Rimbach G. ApoE genotype, cardiovascular risk and responsiveness to dietary fat manipulation. Proc Nutr Soc 2007; 66:183-97. [PMID: 17466101 DOI: 10.1017/s0029665107005435] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Cardiovascular risk is determined by the complex interactions between genetic and environmental factors. The apoE genotype represents the most-widely-studied single nucleotide polymorphism in relation to CVD risk, with >3600 publications cited in PubMed. Although originally described as a mediator of lipoprotein metabolism, the lipoprotein-independent functions of apoE are being increasingly recognised, with limited data available on the potential impact of genotype on these metabolic processes. Furthermore, although meta-analyses suggest that apoE4 carriers may have a 40-50% increased CVD risk, the associations reported in individual studies are highly heterogeneous and it is recognised that environmental factors such as smoking status and dietary fat composition influence genotype-phenotype associations. However, information is often derived from observational studies or small intervention trials in which retrospective genotyping of the cohort results in small group sizes in the rarer E2 and E4 subgroups. Either larger well-standardised intervention trials or smaller trials with prospective recruitment according to apoE genotype are needed to fully establish the impact of diet on genotype-CVD associations and to establish the potential of dietary strategies such as reduced total fat, saturated fat, or increased antioxidant intakes to counteract the increased CVD burden in apoE4 carriers.
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Affiliation(s)
- A M Minihane
- Hugh Sinclair Unit of Human Nutrition, School of Chemistry, Food Biosciences and Pharmacy, University of Reading, Reading RG6 6AP, UK.
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31
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Jordan BD. Genetic influences on outcome following traumatic brain injury. Neurochem Res 2007; 32:905-15. [PMID: 17342413 DOI: 10.1007/s11064-006-9251-3] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Accepted: 12/05/2006] [Indexed: 02/02/2023]
Abstract
Several genes have been implicated as influencing the outcome following traumatic brain injury (TBI). Currently the most extensively studied gene has been APOE. APOE can influence overall and rehabilitation outcome, coma recovery, risk of posttraumatic seizures, as well as cognitive and behavioral functions following TBI. Pathologically, APOE is associated with increased amyloid deposition, amyloid angiopathy, larger intracranial hematomas and more severe contusional injury. The proposed mechanism by which APOE affects the clinicopathological consequences of TBI is multifactorial and includes amyloid deposition, disruption of cytoskeletal stability, cholinergic dysfunction, oxidative stress, neuroprotection and central nervous system plasticity in response to injury. Other putative genes have been less extensively studied and require replication of the clinical findings. The COMT and DRD2 genes may influence dopamine dependent cognitive processes such as executive/frontal lobe functions. Inflammation which is a prominent component in the pathophysiological cascade initiated by TBI, is in part is mediated by the interleukin genes, while apoptosis that occurs as a consequence of TBI may be modulated by polymorphisms of the p53 gene. The ACE gene may affect TBI outcome via mechanisms of cerebral blood flow and/or autoregulation and the CACNA1A gene may exert an influence via the calcium channel and its effect on delayed cerebral edema. Although several potential genes that may influence outcome following TBI have been identified, future investigations are needed to validate these genetic studies and identify new genes that might influence outcome following TBI.
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Affiliation(s)
- Barry D Jordan
- Brain Injury Program, Burke Rehabilitation Hospital, 785 Mamaroneck Avenue, White Plains, NY 10605, USA.
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32
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Zhu X, Lee HG, Perry G, Smith MA. Alzheimer disease, the two-hit hypothesis: an update. Biochim Biophys Acta Mol Basis Dis 2006; 1772:494-502. [PMID: 17142016 DOI: 10.1016/j.bbadis.2006.10.014] [Citation(s) in RCA: 201] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2006] [Revised: 10/23/2006] [Accepted: 10/24/2006] [Indexed: 11/21/2022]
Abstract
Given the relative modality of single-insult models to accurately reflect Alzheimer disease pathogenesis, based on studies on mitogenic and oxidative stress signaling pathways, we proposed a two-hit hypothesis 2 years ago stating that both oxidative stress and mitogenic dysregulation are necessary and sufficient to cause the disease and suggested that it may be a common mechanism for other neurodegenerative diseases as well (X. Zhu, A.K. Raina, G. Perry, M.A. Smith, Alzheimer's disease: the two-hit hypothesis, Lancet Neurol. 3 (2004) 219-226). Recent developments in the field confirm some important predictions of the hypothesis and shed new lights on potential mechanisms regarding how steady state may be achieved in sporadic AD cases and therefore, in our opinion, strengthen the hypothesis, which will be the focus of this review.
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Affiliation(s)
- Xiongwei Zhu
- Department of Pathology, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44106, USA.
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Nunomura A, Castellani RJ, Zhu X, Moreira PI, Perry G, Smith MA. Involvement of oxidative stress in Alzheimer disease. J Neuropathol Exp Neurol 2006; 65:631-41. [PMID: 16825950 DOI: 10.1097/01.jnen.0000228136.58062.bf] [Citation(s) in RCA: 377] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Genetic and lifestyle-related risk factors for Alzheimer disease (AD) are associated with an increase in oxidative stress, suggesting that oxidative stress is involved at an early stage of the pathologic cascade. Moreover, oxidative stress is mechanistically and chronologically associated with other key features of AD, namely, metabolic, mitochondrial, metal, and cell-cycle abnormalities. Contrary to the commonly held notion that pathologic hallmarks of AD signify etiology, several lines of evidence now indicate that aggregation of amyloid-beta and tau is a compensatory response to underlying oxidative stress. Therefore, removal of proteinaceous accumulations may treat the epiphenomenon rather than the disease and may actually enhance oxidative damage. Although some antioxidants have been shown to reduce the incidence of AD, the magnitude of the effect may be modified by individual factors such as genetic predisposition (e.g. apolipoprotein E genotype) and habitual behaviors. Because caloric restriction, exercise, and intellectual activity have been experimentally shown to promote neuronal survival through enhancement of endogenous antioxidant defenses, a combination of dietary regimen of low total calorie and rich antioxidant nutrients and maintaining physical and intellectual activities may ultimately prove to be one of the most efficacious strategies for AD prevention.
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Affiliation(s)
- Akihiko Nunomura
- Department of Psychiatry and Neurology, Asahikawa Medical College, Asahikawa, Japan
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Abstract
It is becoming increasingly clear that genetic factors modify outcome after traumatic brain injury (TBI). The best known example of this is the association between the apolipoprotein E4 allele (APOE epsilon4) and poorer outcomes. However, our knowledge of the many other genes that might influence outcome is still in its infancy. This article will review the basic principles underlying recent advances in genetics, and then describe the current state of knowledge regarding the impact of genetic factors on TBI outcome. We conclude that although genetic advances have implications for prognosis, their biggest contribution will be to elucidate the pathophysiology of TBI, potentially leading to new treatments.
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Affiliation(s)
- Ramon Diaz-Arrastia
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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35
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Frey C, Bonert A, Kratzsch T, Rexroth G, Rösch W, Müller-Spahn F, Maurer K, Müller WE, Eckert A. Apolipoprotein E epsilon 4 is associated with an increased vulnerability to cell death in Alzheimer’s disease. J Neural Transm (Vienna) 2006; 113:1753-61. [PMID: 16736246 DOI: 10.1007/s00702-006-0481-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2005] [Accepted: 03/13/2006] [Indexed: 01/29/2023]
Abstract
The presumption to suffer from Alzheimer's disease (AD) accelerates with aging. One important risk factor seems to be the isoform epsilon 4 of the apolipoprotein E gene (Apo epsilon 4), which increases the risk to develop AD at an earlier age. Furthermore, convincing evidence is provided that apoptotic cell death mechanisms play an important role in neuronal cell death in AD. In the present study, we investigated whether abnormalities in apoptosis and caspase-3 activity can be found at the level of lymphocytes and a T cell subtype, CD4 T cells, from AD patients compared to aged sex- and ApoE genotype-matched non-demented controls. Under different experimental conditions (at baseline or after in vitro incubation in the presence of proapoptotic stimuli) increased levels of apoptosis and enhanced caspase-3 activity were detected in lymphocytes from AD patients. This difference was most pronounced in the CD4(+) T cell subtype. Notably, we found a significant increase of apoptotic cells and caspase-3 activity in lymphocytes from AD patients bearing one or two alleles of the ApoE4 compared to non-E4 carriers. Again, these effects were strongest in CD4(+) T cells. Circulating amyloid-beta (A beta) levels did not differ between AD patients bearing ApoE4 and non-ApoE4 and age-matched controls. Therefore, it is likely that circulating A beta is not responsible for the observed effects, which might rather reflect an ongoing systemic response in AD, e.g. an increase in CD95 expression.
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Affiliation(s)
- C Frey
- Department of Pharmacology, Biocenter, University of Frankfurt, Germany
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36
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Hu P, Bretsky P, Crimmins EM, Guralnik JM, Reuben DB, Seeman TE. Association Between Serum Beta-Carotene Levels and Decline of Cognitive Function in High-Functioning Older Persons With or Without Apolipoprotein E 4 Alleles: MacArthur Studies of Successful Aging. J Gerontol A Biol Sci Med Sci 2006; 61:616-20. [PMID: 16799145 DOI: 10.1093/gerona/61.6.616] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Growing evidence from animal studies suggests an interaction between antioxidants and apolipoprotein E (APOE) alleles on cognitive functioning. We used data from a 7-year cohort study of high-functioning older persons to explore whether the associations between serum beta-carotene level and subsequent decline of cognitive function differed by APOE 4 genotype. METHODS Baseline information on sociodemographic characteristics, serum beta-carotene level, inflammation markers, APOE genotype, and cognitive functioning measured by a 9-item Short Portable Mental Status Questionnaire (SPMSQ) was obtained in 455 survivors. Multivariable logistic regression analyses were used to examine the relation between high serum beta-carotene level and risk of SPMSQ score decline in participants with or without APOE 4 alleles, while adjusting for age, sex, race, baseline SPMSQ score, and other covariates. RESULTS Nine (2%) study participants had homozygous and 97 (21%) had heterozygous APOE 4 alleles. Two hundred forty-nine (55%) had decline of SPMSQ scores during the follow-up. The presence of an APOE 4 allele was associated with higher risk and larger magnitude of SPMSQ score decline. The adjusted odds ratio of high beta-carotene level for cognitive decline was 0.11 (95% confidence interval, 0.02-0.57) in participants with at least one APOE 4 allele and 0.89 (95% confidence interval, 0.54-1.47) among those who were APOE 4 negative. CONCLUSION Among high-functioning older persons, antioxidants and beta-carotene in particular may offer protection from cognitive decline in persons with greater genetic susceptibility as evidenced by the presence of the APOE 4 allele.
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Affiliation(s)
- Peifeng Hu
- Multicampus Program in Geriatric Medicine and Gerontology, UCLA School of Medicine, 10945 Le Conte Avenue, Suite 2339, Los Angeles, CA 90095-1687, USA.
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Mazur-Kolecka B, Dickson D, Frackowiak J. Induction of vascular amyloidosis-β by oxidative stress depends on APOE genotype. Neurobiol Aging 2006; 27:804-14. [PMID: 15993987 DOI: 10.1016/j.neurobiolaging.2005.04.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2004] [Revised: 04/13/2005] [Accepted: 04/26/2005] [Indexed: 11/19/2022]
Abstract
The reduced antioxidant defense in apolipoprotein E epsilon4/epsilon4 carriers may contribute to beta-amyloidosis. Previously we found that Fe(2+)-induced oxidative stress caused greater protein oxidation in epsilon4/epsilon4 than in epsilon3/epsilon3 human brain vascular smooth muscle cells. Moreover, Fe(2+) induced lysosomal accumulation of endogenous Abeta and APOE in cultured cells, and Abeta deposition in vascular tunica media in organotypic cultures of brain vessels. Here we demonstrated that Fe(2+) enhanced an uptake of exogenous Abeta 1-40 and its deposition together with APOE in lysosomes in myocytes. Abeta deposits were associated with lipid-peroxidation and protein ubiquitination, and were more abundant and stable in epsilon4/epsilon4 than in epsilon3/epsilon3 cells. In organotypic cultures of brain vessels Fe(2+) induced deposition of non-fibrillar and fibrillar Abeta 1-40 in vascular tunica media. We hypothesize that locally increased concentrations of iron induce accumulation of exogenous and endogenous Abeta in SMCs, triggering beta-amyloid angiopathy. The greater susceptibility of epsilon4 carriers to Fe(2+) ions may result in an increased risk of beta-amyloidosis.
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Affiliation(s)
- Bozena Mazur-Kolecka
- New York State Institute for Basic Research in Developmental Disabilities, Department of Developmental Neurobiology, 1050 Forest Hill Road, Staten Island, NY 10314, USA.
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Robson KJH, Lehmann DJ, Wimhurst VLC, Livesey KJ, Combrinck M, Merryweather-Clarke AT, Warden DR, Smith AD. Synergy between the C2 allele of transferrin and the C282Y allele of the haemochromatosis gene (HFE) as risk factors for developing Alzheimer's disease. J Med Genet 2004; 41:261-5. [PMID: 15060098 PMCID: PMC1735734 DOI: 10.1136/jmg.2003.015552] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND There is evidence that iron may play a role in the pathology of Alzheimer's disease (AD). There may be genetic factors that contribute to iron deposition resulting in tissue damage thus exacerbating AD. METHODS We have genotyped 269 healthy elderly controls, 191 cases with definite or probable AD, and 69 with mild cognitive impairment (MCI) from the OPTIMA cohort. RESULTS We have examined the interaction between the C2 variant of the transferrin (TF) gene and the C282Y allele of the haemochromatosis (HFE) gene as risk factors for developing AD. Our results showed that each of the two variants was associated with an increased risk of AD only in the presence of the other. Neither allele alone had any effect. Carriers of both variants were at 5 times greater risk of AD compared with all others. The interaction was significant by logistic regression (p = 0.014) and by synergy factor analysis (p = 0.015, synergy factor = 5.1). Further, carriers of these two alleles plus apolipoprotein E epsilon4 (APOE4) were at still higher risk of AD: of the 14 tri-carriers of the three variants, identified in this study, 12 had AD and two MCI. CONCLUSION We suggest that the combination of TF C2 and HFE C282Y may lead to an excess of redox-active iron and the induction of oxidative stress in neurones, which is exacerbated in carriers of APOE4. Since 4% of Northern Europeans carry the two iron-related variants and since iron overload is a treatable condition, these results merit replication.
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Affiliation(s)
- K J H Robson
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK.
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39
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Abstract
There are many lines of evidence showing that oxidative stress and aberrant mitogenic changes have important roles in the pathogenesis of Alzheimer's disease (AD). However, although both oxidative stress and cell cycle-related abnormalities are early events, occurring before any cytopathology, the relation between these two events, and their role in pathophysiology was, until recently, unclear. However, on the basis of studies of mitogenic and oxidative stress signalling pathways in AD, we proposed a "two-hit hypothesis" which states that although either oxidative stress or abnormalities in mitotic signalling can independently serve as initiators, both processes are necessary to propagate disease pathogenesis. In this paper, we summarise evidence for oxidative stress and abnormal mitotic alterations in AD and explain the two-hit hypothesis by describing how both mechanisms are necessary and invariant features of disease.
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Affiliation(s)
- Xiongwei Zhu
- Institute of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, USA
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40
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Palomo T, Archer T, Beninger RJ, Kostrzewa RM. Gene-environment interplay in neurogenesis and neurodegeneration. Neurotox Res 2004; 6:415-34. [PMID: 15639777 DOI: 10.1007/bf03033279] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Factors associated with predisposition and vulnerability to neurodegenerative disorders may be described usefully within the context of gene-environment interplay. There are many identified genetic determinants for so-called genetic disorders, and it is possible to duplicate many elements of recognized human neurodegenerative disorders in either knock-in or knock-out mice. However, there are similarly, many identifiable environmental influences on outcomes of the genetic defects; and the course of a progressive neurodegenerative disorder can be greatly modified by environmental elements. Constituent cellular defense mechanisms responsive to the challenge of increased reactive oxygen species represent only one crossroad whereby environment can influence genetic predisposition. In this paper we highlight some of the major neurodegenerative disorders and discuss possible links of gene-environment interplay. The process of adult neurogenesis in brain is also presented as an additional element that influences gene-environment interplay. And the so-called priming processes (i.e., production of receptor supersensitization by repeated drug dosing), is introduced as yet another process that influences how genes and environment ultimately and co-dependently govern behavioral ontogeny and outcome. In studies attributing the influence of genetic alteration on behavioral phenotypy, it is essential to carefully control environmental influences.
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Affiliation(s)
- Tomás Palomo
- Servicio Psiquiátrico, Hospital Universitario 12 de Octubre, Avda. de Córdoba s/n, 28041 Madrid, Spain
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41
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Abstract
Amyloid plaques and neurofibrillary tangles are the neuropathological hallmarks of Alzheimer's disease (AD), but no conclusive evidence has emerged showing that these hallmarks are the cause and not a product of the disease. Many studies have implicated oxidation and inflammation in the AD process, and there is growing evidence that abnormalities of lipid metabolism also play a role. Using epidemiology to elucidate risk factors and histological changes to suggest possible mechanisms, the hypothesis is advanced that dietary lipids are the principal risk factor for the development of late-onset sporadic AD. The degree of saturation of fatty acids and the position of the first double bond in essential fatty acids are the most critical factors determining the effect of dietary fats on the risk of AD, with unsaturated fats and n-3 double bonds conferring protection and an overabundance of saturated fats or n-6 double bonds increasing the risk. The interaction of dietary lipids and apolipoprotein E isoforms may determine the risk and rate of sustained autoperoxidation within cellular membranes and the efficacy of membrane repair. Interventions involving dietary lipids and lipid metabolism show great promise in slowing or possibly averting the development of AD, including dietary changes, cholesterol-modifying agents and antioxidants.
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Affiliation(s)
- Janelle L Cooper
- The Memory Center, Affinity Health System, Oshkosh, Wisconsin 54902, USA.
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42
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Swaab DF, Dubelaar EJG, Hofman MA, Scherder EJA, van Someren EJW, Verwer RWH. Brain aging and Alzheimer's disease; use it or lose it. PROGRESS IN BRAIN RESEARCH 2002; 138:343-73. [PMID: 12432778 DOI: 10.1016/s0079-6123(02)38086-5] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
(1) Alzheimer's disease is a multifactorial disease in which age and APOE-epsilon 4 are important risk factors. (2) The neuropathological hallmarks of AD, i.e. amorphous plaques, neuritic plaques (NPs), pretangles, neurofibrillary tangles (NFT) and cell death are not part of a single pathogenetic cascade but may occur independently. (3) In brain areas where classical AD changes, i.e. NPs and NFTs, are present, such as the CA1 area of the hippocampus, the nucleus basalis of Meynert and the tuberomamillary nucleus, a decreased metabolic rate is found. The decreased metabolic rate appears not to be induced by the presence of pretangles, NFT or NPs. (4) Decreased metabolic rate may precede cognitive impairment and is thus an early occurring hallmark of AD, which, in principle, may be reversible. The observation that the administration of glucose or insulin enhances memory in AD patients also supports the view that AD has a metabolic basis. (5) Moreover, several observations in postmortem brain indicate that activated neurons are better able to withstand aging and AD, a phenomenon paraphrased by us as 'use it or lose it'. (6) It is, therefore, attractive to direct the development of therapeutic strategies towards restimulation of neuronal metabolic rate in order to improve cognition and other symptoms in AD. A number of pharmacological and non-pharmacological studies support the concept that activation of the brain has beneficial effects and may, to a certain degree, restore several aspects of cognition and other central functions. For instance, the circadian system may be restimulated in AD patients by exposing them to more light or transcutaneous nerve stimulation. A procedure has been developed to culture human postmortem brain tissue that allows testing of the efficacy of putative stimulatory compounds such as neurotrophins.
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Affiliation(s)
- D F Swaab
- Netherlands Institute for Brain Research, Meibergdreef 33, 1105 AZ Amsterdam, The Netherlands.
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Butterfield DA, Lauderback CM. Lipid peroxidation and protein oxidation in Alzheimer's disease brain: potential causes and consequences involving amyloid beta-peptide-associated free radical oxidative stress. Free Radic Biol Med 2002; 32:1050-60. [PMID: 12031889 DOI: 10.1016/s0891-5849(02)00794-3] [Citation(s) in RCA: 735] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Amyloid beta-peptide (A(beta)) is heavily deposited in the brains of Alzheimer's disease (AD) patients, and free radical oxidative stress, particularly of neuronal lipids and proteins, is extensive. Recent research suggests that these two observations may be linked by A(beta)-induced oxidative stress in AD brain. This review summarizes current knowledge on phospholipid peroxidation and protein oxidation in AD brain, one potential cause of this oxidative stress, and consequences of A(beta)-induced lipid peroxidation and protein oxidation in AD brain.
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Affiliation(s)
- D Allan Butterfield
- Department of Chemistry, Center of Membrane Sciences, and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40506-0055, USA.
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44
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Lauderback CM, Kanski J, Hackett JM, Maeda N, Kindy MS, Butterfield DA. Apolipoprotein E modulates Alzheimer's Abeta(1-42)-induced oxidative damage to synaptosomes in an allele-specific manner. Brain Res 2002; 924:90-7. [PMID: 11743999 DOI: 10.1016/s0006-8993(01)03228-0] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Several functional differences have been reported among the three human e2, e3, and e4 alleles of apolipoprotein E (apoE). One functional difference lies in the antioxidant potential of these alleles; e4 has the poorest potential. Interestingly, e4 also correlates with increased oxidative damage in the Alzheimer's disease (AD) brain, which may explain why the inheritance of the e4 allele is a risk factor for the onset of AD. Beta-amyloid (Abeta) is also intimately involved in AD and promotes oxidative damage in vitro; therefore, we have examined the role of the different apoE alleles in modulating Abeta(1-42)-induced oxidation to synaptosomes. Measurement of specific markers of oxidation in synaptosomes isolated from mice that express one of the human apoE alleles indicates that Abeta-induced increases of these markers can be modulated by apoE in an allele-dependent manner (e2>e3>e4). Increases in reactive oxygen species formation and protein and lipid oxidation were always greatest in e4 synaptosomes as compared to e2 and e3 synaptosomes. Our data support the role of apoE as a modulator of Abeta toxicity and, consistent with the antioxidant potentials of the three alleles, suggest that the e4 allele may not be as effective in this role as the e2 or e3 alleles of apoE. These results are discussed with reference to mechanistic implications for neurodegeneration in the AD brain.
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Yokota T, Igarashi K, Uchihara T, Jishage K, Tomita H, Inaba A, Li Y, Arita M, Suzuki H, Mizusawa H, Arai H. Delayed-onset ataxia in mice lacking alpha -tocopherol transfer protein: model for neuronal degeneration caused by chronic oxidative stress. Proc Natl Acad Sci U S A 2001; 98:15185-90. [PMID: 11752462 PMCID: PMC65004 DOI: 10.1073/pnas.261456098] [Citation(s) in RCA: 198] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
alpha-Tocopherol transfer protein (alpha-TTP) maintains the concentration of serum alpha-tocopherol (vitamin E), one of the most potent fat-soluble antioxidants, by facilitating alpha-tocopherol export from the liver. Mutations of the alpha-TTP gene are linked to ataxia with isolated vitamin E deficiency (AVED). We produced a model mouse of AVED by deleting the alpha-TTP gene, which showed ataxia and retinal degeneration after 1 year of age. Because the brain alpha-TTP functions in maintaining alpha-tocopherol levels in the brain, alpha-tocopherol was completely depleted in the alpha-TTP(-/-) mouse brain, and the neurological phenotype of alpha-TTP(-/-) mice is much more severe than that of wild-type mice when maintained on an alpha-tocopherol-deficient diet. Lipid peroxidation in alpha-TTP(-/-) mice brains showed a significant increase, especially in degenerating neurons. alpha-Tocopherol supplementation suppressed lipid peroxidation and almost completely prevented the development of neurological symptoms. This therapy almost completely corrects the abnormalities in a mouse model of human neurodegenerative disease. Moreover, alpha-TTP(-/-) mice may prove to be excellent animal models of delayed onset, slowly progressive neuronal degeneration caused by chronic oxidative stress.
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Affiliation(s)
- T Yokota
- Department of Neurology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
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Nunomura A, Perry G, Aliev G, Hirai K, Takeda A, Balraj EK, Jones PK, Ghanbari H, Wataya T, Shimohama S, Chiba S, Atwood CS, Petersen RB, Smith MA. Oxidative damage is the earliest event in Alzheimer disease. J Neuropathol Exp Neurol 2001; 60:759-67. [PMID: 11487050 DOI: 10.1093/jnen/60.8.759] [Citation(s) in RCA: 1311] [Impact Index Per Article: 57.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Recently, we demonstrated a significant increase of an oxidized nucleoside derived from RNA, 8-hydroxyguanosine (8OHG), and an oxidized amino acid, nitrotyrosine in vulnerable neurons of patients with Alzheimer disease (AD). To determine whether oxidative damage is an early- or end-stage event in the process of neurodegeneration in AD, we investigated the relationship between neuronal 8OHG and nitrotyrosine and histological and clinical variables, i.e. amyloid-beta (A beta) plaques and neurofibrillary tangles (NFT), as well as duration of dementia and apolipoprotein E (ApoE) genotype. Our findings show that oxidative damage is quantitatively greatest early in the disease and reduces with disease progression. Surprisingly, we found that increases in A beta deposition are associated with decreased oxidative damage. These relationships are more significant in ApoE epsilon4 carriers. Moreover, neurons with NFT show a 40%-56% decrease in relative 8OHG levels compared with neurons free of NFT. Our observations indicate that increased oxidative damage is an early event in AD that decreases with disease progression and lesion formation. These findings suggest that AD is associated with compensatory changes that reduce damage from reactive oxygen.
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Affiliation(s)
- A Nunomura
- Institute of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, USA
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