1
|
Dang C, Wang Y, Li Q, Lu Y. Neuroimaging modalities in the detection of Alzheimer's disease-associated biomarkers. PSYCHORADIOLOGY 2023; 3:kkad009. [PMID: 38666112 PMCID: PMC11003434 DOI: 10.1093/psyrad/kkad009] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/04/2023] [Accepted: 06/20/2023] [Indexed: 04/28/2024]
Abstract
Alzheimer's disease (AD) is the most common cause of dementia. Neuropathological changes in AD patients occur up to 10-20 years before the emergence of clinical symptoms. Specific diagnosis and appropriate intervention strategies are crucial during the phase of mild cognitive impairment (MCI) and AD. The detection of biomarkers has emerged as a promising tool for tracking the efficacy of potential therapies, making an early disease diagnosis, and prejudging treatment prognosis. Specifically, multiple neuroimaging modalities, including magnetic resonance imaging (MRI), positron emission tomography, optical imaging, and single photon emission-computed tomography, have provided a few potential biomarkers for clinical application. The MRI modalities described in this review include structural MRI, functional MRI, diffusion tensor imaging, magnetic resonance spectroscopy, and arterial spin labelling. These techniques allow the detection of presymptomatic diagnostic biomarkers in the brains of cognitively normal elderly people and might also be used to monitor AD disease progression after the onset of clinical symptoms. This review highlights potential biomarkers, merits, and demerits of different neuroimaging modalities and their clinical value in MCI and AD patients. Further studies are necessary to explore more biomarkers and overcome the limitations of multiple neuroimaging modalities for inclusion in diagnostic criteria for AD.
Collapse
Affiliation(s)
- Chun Dang
- Department of Periodical Press, West China Hospital, Sichuan University, Chengdu 610000, China
| | - Yanchao Wang
- Department of Neurology, Chifeng University of Affiliated Hospital, Chifeng 024000, China
| | - Qian Li
- Department of Neurology, the Second Affiliated Hospital of Harbin Medical University, Harbin 150081, China
| | - Yaoheng Lu
- Department of General Surgery, Chengdu Integrated Traditional Chinese Medicine and Western Medicine Hospital, Chengdu 610000, China
| |
Collapse
|
2
|
Sajad M, Kumar R, Thakur SC. History in Perspective: The Prime Pathological Players and Role of Phytochemicals in Alzheimer’s Disease. IBRO Neurosci Rep 2022; 12:377-389. [PMID: 35586776 PMCID: PMC9108734 DOI: 10.1016/j.ibneur.2022.04.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 04/25/2022] [Indexed: 11/01/2022] Open
Abstract
Alzheimer's disease is a steadily progressive, irreversible neurological disorder that is most frequently categorized under the umbrella term "neurodegeneration". Several attempts are underway to clarify the pathogenic mechanisms, identify the aetiologies, and determine a pathway by which the therapeutic steps can be implemented. Oxidative stress is one of the pathogenic processes, which is commonly believed to be associated with neurodegenerative diseases. Accumulation of extracellular amyloid-β protein (Aβ), hyperphosphorylation of tau, initiation of neurometabolic reactions characterized by the loss of neuronal function and synaptic failure, and decreased or lost learning capability and memory function are the most central neuropathological characteristics of AD. According to the amyloid cascade hypothesis, the enhanced deposition of Aβ deposits and neurofibrillary tangles due to hyperphosphorylation of Tau activates the cascade reactions in the brain. These reactions affect the synaptic activity and activation of microglia, which results in neuroinflammation due to enhanced immune function. Plant-based phytochemicals have also been used long ago against several diseases. Phytoconstituents play a significant neuroprotective property by preventing the pathophysiology of the disease. In this review, we have discussed the formation and crosstalk between amyloid and tau pathologies as well as the effect of neuroinflammation on the progression of AD. We have specifically focused on the formation of NFT, β-amyloids, inflammation, and pathophysiology of AD and the role of phytochemicals in the prevention of AD. AD is an insidious, slowly progressive, and neurodegenerative disorder. Common symptoms are memory loss, difficulty in recalling, and understanding. β-amyloids and Neurofibrillary tangles are the main factors in AD pathogenesis. Activated microglia and oxidative stress have different effects on AD progression. Phytochemicals show a key role against AD by inhibiting several pathways.
Collapse
|
3
|
He H, Ding S, Jiang C, Wang Y, Luo Q, Wang Y. Information Flow Pattern in Early Mild Cognitive Impairment Patients. Front Neurol 2021; 12:706631. [PMID: 34858306 PMCID: PMC8631864 DOI: 10.3389/fneur.2021.706631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 10/11/2021] [Indexed: 12/05/2022] Open
Abstract
Purpose: To investigate the brain information flow pattern in patients with early mild cognitive impairment (EMCI) and explore its potential ability of differentiation and prediction for EMCI. Methods: In this study, 49 patients with EMCI and 40 age- and sex-matched healthy controls (HCs) with available resting-state functional MRI images and neurological measures [including the neuropsychological evaluation and cerebrospinal fluid (CSF) biomarkers] were included from the Alzheimer's Disease Neuroimaging Initiative. Functional MRI measures including preferred information flow direction between brain regions and preferred information flow index of each brain region parcellated by the Atlas of Intrinsic Connectivity of Homotopic Areas (AICHA) were calculated by using non-parametric multiplicative regression-Granger causality analysis (NPMR-GCA). Edge- and node-wise Student's t-test was conducted for between-group comparison. Support vector classification was performed to differentiate EMCI from HC. The least absolute shrinkage and selection operator (lasso) regression were used to evaluate the predictive ability of information flow measures for the neurological state. Results: Compared to HC, disturbed preferred information flow directions between brain regions involving default mode network (DMN), executive control network (ECN), somatomotor network (SMN), and visual network (VN) were observed in patients with EMCI. An altered preferred information flow index in several brain regions (including the thalamus, posterior cingulate, and precentral gyrus) was also observed. Classification accuracy of 80% for differentiating patients with EMCI from HC was achieved by using the preferred information flow directions. The preferred information flow directions have a good ability to predict memory and executive function, level of amyloid β, tau protein, and phosphorylated tau protein with the high Pearson's correlation coefficients (r > 0.7) between predictive and actual neurological measures. Conclusion: Patients with EMCI were presented with a disturbed brain information flow pattern, which could help clinicians to identify patients with EMCI and assess their neurological state.
Collapse
Affiliation(s)
- Haijuan He
- Department of Radiology, The First Affiliated Hospital, Xinjiang Medical University, Xinjiang, China
| | - Shuang Ding
- Department of Radiology, The First Affiliated Hospital, Xinjiang Medical University, Xinjiang, China
| | - Chunhui Jiang
- Department of Radiology, The First Affiliated Hospital, Xinjiang Medical University, Xinjiang, China
| | - Yuanyuan Wang
- Department of Radiology, The First Affiliated Hospital, Xinjiang Medical University, Xinjiang, China
| | - Qiaoya Luo
- Department of Radiology, The First Affiliated Hospital, Xinjiang Medical University, Xinjiang, China
| | - Yunling Wang
- Department of Radiology, The First Affiliated Hospital, Xinjiang Medical University, Xinjiang, China
| | | |
Collapse
|
4
|
Ben Ayed I, Castor-Guyonvarch N, Amimour S, Naija S, Aouichaoui C, Ben Omor S, Tabka Z, El Massioui F. Acute Exercise and Cognitive Function in Alzheimer's Disease. J Alzheimers Dis 2021; 82:749-760. [PMID: 34092631 DOI: 10.3233/jad-201317] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Many studies have shown the impact of acute aerobic exercises (AAE) on cognition in healthy adults or at a pre-dementia stage. Few studies, however, have explored the positive effects of AAE in moderate Alzheimer's disease (ADM) patients. OBJECTIVE Evaluating the effect of AAE on cognitive functions in ADM patients. METHODS Overall, 79 (age: 69.62±0.99) ADM patients were recruited. Participants were divided into three groups according to the task: aerobic exercises done alone or combined with cognitive games presented on a screen, and a control group who performed a reading task. The aerobic exercise protocol consisted of a 20-min cycling exercise of moderate intensity, corresponding to 60%of the individual target maximal heart rate recorded in a 6-minute walking test. The participants' cognition was monitored before and after the intervention using the Tower of Hanoi, Digit Span, and Stroop tasks. RESULTS After the exercise, the participants' attention in both the physical and combined groups improved for the Stroop, the forward and backward Digit Span tasks, as well as the time taken to solve the Tower of Hanoi, although no significant differences were found in the number of moves taken in the latter. By contrast, the control group did not show any significant improvement for most of the cognitive tasks after the reading session. CONCLUSION Current evidence suggests that AAE may help to improve cognitive functions in ADM patients. This improvement is enhanced when the exercise is combined with cognitive games. Safe and progressive types of exercises should be promoted among ADM patients.
Collapse
Affiliation(s)
- Ines Ben Ayed
- Laboratory of Physiology and Functional Explorations, Laboratory of Exercise Physiology and Physiopathology (LR19ES09), Faculty of Medicine of Sousse, Sousse, Tunisia.,Laboratory of Human and Artificial Cognition (EA 4004), Psychology UFR, University of Vincennes/Saint-Denis, Paris, France
| | - Naomie Castor-Guyonvarch
- Laboratory of Human and Artificial Cognition (EA 4004), Psychology UFR, University of Vincennes/Saint-Denis, Paris, France
| | - Souad Amimour
- Laboratory of Human and Artificial Cognition (EA 4004), Psychology UFR, University of Vincennes/Saint-Denis, Paris, France.,University of Algiers 2, Bouzaréah, Algeria
| | - Salma Naija
- Neurology Department, University Hospital Sahloul Sousse, Sahloul, Sousse, Tunisia
| | - Chirine Aouichaoui
- Laboratory of Physiology and Functional Explorations, Laboratory of Exercise Physiology and Physiopathology (LR19ES09), Faculty of Medicine of Sousse, Sousse, Tunisia
| | - Sana Ben Omor
- Neurology Department, University Hospital Sahloul Sousse, Sahloul, Sousse, Tunisia
| | - Zouhair Tabka
- Laboratory of Physiology and Functional Explorations, Laboratory of Exercise Physiology and Physiopathology (LR19ES09), Faculty of Medicine of Sousse, Sousse, Tunisia
| | - Farid El Massioui
- Laboratory of Human and Artificial Cognition (EA 4004), Psychology UFR, University of Vincennes/Saint-Denis, Paris, France
| |
Collapse
|
5
|
Yan T, Liu T, Ai J, Shi Z, Zhang J, Pei G, Wu J. Task-induced activation transmitted by structural connectivity is associated with behavioral performance. Brain Struct Funct 2021; 226:1437-1452. [DOI: 10.1007/s00429-021-02249-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 02/27/2021] [Indexed: 12/18/2022]
|
6
|
Liu X, Wang K, Wei X, Xie T, Lv B, Zhou Q, Wang X. Interaction of NF-κB and Wnt/β-catenin Signaling Pathways in Alzheimer's Disease and Potential Active Drug Treatments. Neurochem Res 2021; 46:711-731. [PMID: 33523396 DOI: 10.1007/s11064-021-03227-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 11/24/2020] [Accepted: 01/02/2021] [Indexed: 12/25/2022]
Abstract
The most important neuropathological features of Alzheimer's disease (AD) are extracellular amyloid-β protein (Aβ) deposition, tau protein hyperphosphorylation and activation of neurometabolic reaction in the brain accompanied by neuronal and synaptic damage, and impaired learning and memory function. According to the amyloid cascade hypothesis, increased Aβ deposits in the brain to form the core of the senile plaques that initiate cascade reactions, affecting the synapses and stimulating activation of microglia, resulting in neuroinflammation. A growing number of studies has shown that NF-κB and Wnt/β-catenin pathways play important roles in neurodegenerative diseases, especially AD. In this review, we briefly introduce the connection between neuroinflammation-mediated synaptic dysfunction in AD and elaborated on the mechanism of these two signaling pathways in AD-related pathological changes, as well as their interaction. Based on our interest in natural compounds, we also briefly introduce and conduct preliminary screening of potential therapeutics for AD.
Collapse
Affiliation(s)
- Xiao Liu
- State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Kaiyue Wang
- State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Xing Wei
- State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Tian Xie
- State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Bin Lv
- State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Qian Zhou
- Department of Anatomy, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishiku, Kitakyushu, 807-8555, Japan
| | - Xiaoying Wang
- State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China. .,College of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China.
| |
Collapse
|
7
|
Bastin C, Giacomelli F, Miévis F, Lemaire C, Guillaume B, Salmon E. Anosognosia in Mild Cognitive Impairment: Lack of Awareness of Memory Difficulties Characterizes Prodromal Alzheimer's Disease. Front Psychiatry 2021; 12:631518. [PMID: 33868048 PMCID: PMC8044313 DOI: 10.3389/fpsyt.2021.631518] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 03/08/2021] [Indexed: 12/29/2022] Open
Abstract
While anosognosia is often present in Alzheimer's disease, the degree of awareness of cognitive difficulties in the earlier stages, such as Mild Cognitive Impairment (MCI), is less clear. Using a questionnaire and Feeling-of-Knowing tasks, the aims of this study were (1) to test the hypothesis that anosognosia is present specifically in prodromal AD stage in patients that, owing to a more severe AD neuropathology, will rapidly progress to overt dementia and (2) to assess the neural bases of self-awareness for memory functioning. A group of 44 patients with amnestic MCI and a group of 29 healthy older participants (CTRL) performed two Feeling-of-Knowing tasks (episodic and semantic FOK) and responded to the Functional Memory Scale (MARS), also completed by one of their relatives. They underwent FDG-PET and structural MRI. The participants were followed clinically for 4 years. At the end of follow-up, 23 patients with MCI developed Alzheimer's disease (converters) and 21 patients still presented symptoms of MCI without progression (non-converters). The analyses focused on the data from inclusion stratified according to clinical status 4 years later (converters, non-converters, CTRL). On the episodic FOK task, converters patients overestimated their ability to later recognize unrecalled words and they showed prediction accuracy (Hamann coefficient) at the level of chance. No difficulty was observed in any group with the semantic FOK task. On the MARS, converters patients had a higher anosognosia score than non-converters patients and CTRL, which did not differ from each other. Correlations between self-awareness scores and neuroimaging data using small volume correction analyses in a priori regions of interest in converters indicated that inaccurate episodic FOK judgments was related to changes in brain areas that might support interpretation of retrieved content for judging the likelihood of recognition. For the MARS, the association between anosognosia and decreased gray matter density of the left inferior prefrontal cortex in converters might indicate poor inhibition over outdated personal knowledge. In amnestic MCI, anosognosia could be an early sign of neurodegeneration in brain areas that would support control mechanisms over memory representations.
Collapse
Affiliation(s)
- Christine Bastin
- GIGA-Cyclotron Research Center-in vivo Imaging, University of Liège, Liège, Belgium.,F.R.S.-Fonds National de la Recherche Scientifique, Bruxelles, Belgium
| | - Fabrice Giacomelli
- GIGA-Cyclotron Research Center-in vivo Imaging, University of Liège, Liège, Belgium
| | - Frédéric Miévis
- GIGA-Cyclotron Research Center-in vivo Imaging, University of Liège, Liège, Belgium
| | - Christian Lemaire
- GIGA-Cyclotron Research Center-in vivo Imaging, University of Liège, Liège, Belgium
| | | | - Eric Salmon
- GIGA-Cyclotron Research Center-in vivo Imaging, University of Liège, Liège, Belgium.,Memory Clinic, CHU Liège, Liège, Belgium
| |
Collapse
|