Induced Pluripotent Stem Cell-Derived Neural Precursors Improve Memory, Synaptic and Pathological Abnormalities in a Mouse Model of Alzheimer’s Disease

Alzheimer’s disease (AD) is the most common type of dementia in the elderly population. The disease is characterized by progressive memory loss, cerebral atrophy, extensive neuronal loss, synaptic alterations, brain inflammation, extracellular accumulation of amyloid-β (Aβ) plaques, and intracellular accumulation of hyper-phosphorylated tau (p-tau) protein. Many recent clinical trials have failed to show therapeutic benefit, likely because at the time in which patients exhibit clinical symptoms the brain is irreversibly damaged. In recent years, induced pluripotent stem cells (iPSCs) have been suggested as a promising cell therapy to recover brain functionality in neurodegenerative diseases such as AD. To evaluate the potential benefits of iPSCs on AD progression, we stereotaxically injected mouse iPSC-derived neural precursors (iPSC-NPCs) into the hippocampus of aged triple transgenic (3xTg-AD) mice harboring extensive pathological abnormalities typical of AD. Interestingly, iPSC-NPCs transplanted mice showed improved memory, synaptic plasticity, and reduced AD brain pathology, including a reduction of amyloid and tangles deposits. Our findings suggest that iPSC-NPCs might be a useful therapy that could produce benefit at the advanced clinical and pathological stages of AD.

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MR Brain Screening using Optimization Techniques – A survey

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405617666211126154101 ◽

2021 ◽

Vol 17 ◽

Author(s):

Chitradevi D ◽

Prabha S.

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Clinical Symptoms ◽

Memory Loss ◽

Amyloid Β ◽

Cell Loss ◽

Optimization Techniques ◽

Amyloid Β Protein ◽

The Brain ◽

Brain Tissues

Background: Alzheimer’s disease (AD) is associated with Dementia, and it is also a memory syndrome in the brain. It affects the brain tissues and causes major changes in day-to-day activities. Aging is a major cause of Alzheimer's disease. AD is characterized by two pathological hallmarks as, Amyloid β protein and neurofibrillary tangles of hyperphosphorylated tau protein. The imaging hallmarks for Alzheimer’s disease are namely, swelling, shrinkage of brain tissues due to cell loss, and atrophy in the brain due to protein dissemination. Based on the survey, 60% to 80% of dementia patients belong to Alzheimer’s disease. Introduction: AD is now becoming an increasing and important brain disease. The goal of AD pathology is to cause changes/damage in brain tissues. Alzheimer's disease is thought to begin 20 years or more before symptoms appear, with tiny changes in the brain that are undetectable to the person affected. The changes in a person's brain after a few years are noticeable through symptoms such as language difficulties and memory loss. Neurons in different parts of the brain have detected symptoms such as cognitive impairments and learning disabilities. In this case, neuroimaging tools are necessary to identify the development of pathology which relates to the clinical symptoms. Methods: Several approaches have been tried during the last two decades for brain screening to analyse AD with the process of pre-processing, segmentation and classification. Different individual such as Grey Wolf optimization, Lion Optimization, Ant Lion Optimization and so on. Similarly, hybrid optimization techniques are also attempted to segment the brain sub-regions which helps in identifying the bio-markers to analyse AD. Conclusion: This study discusses a review of neuroimaging technologies for diagnosing Alzheimer's disease, as well as the discovery of hallmarks for the disease and the methodologies for finding hallmarks from brain images to evaluate AD. According to the literature review, most of the techniques predicted higher accuracy (more than 90%), which is beneficial for assessing and screening neurodegenerative illness, particularly Alzheimer's disease.

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Probiotic Releasing Angiotensin (1-7) in a Drosophila Model of Alzheimer’s Disease Produces Sex-Specific Effects on Cognitive Function

Journal of Alzheimer s Disease ◽

10.3233/jad-210464 ◽

2021 ◽

pp. 1-13

Author(s):

C. Aaron Smith ◽

Haddon Smith ◽

Lisa Roberts ◽

Lori Coward ◽

Gregory Gorman ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Therapeutic Potential ◽

Memory Loss ◽

Amyloid Β ◽

Kynurenine Pathway ◽

Lactobacillus Paracasei ◽

Amyloid Β Protein ◽

Complex Disorders ◽

Model Of Alzheimer’S Disease

Background: While extensive research on the brain has failed to identify effective therapies, using probiotics to target the gut microbiome has shown therapeutic potential in Alzheimer’s disease (AD). Genetically modified probiotics (GMP) are a promising strategy to deliver key therapeutic peptides with high efficacy and tissue specificity. Angiotensin (Ang)-(1-7) levels inversely correlate to AD severity, but its administration is challenging. Our group has successfully established a GMP-based method of Ang-(1-7) delivery. Objective: Since Drosophila represents an excellent model to study the effect of probiotics on complex disorders in a high throughput manner, we tested whether oral supplementation with Lactobacillus paracasei releasing Ang-(1-7) (LP-A) delays memory loss in a Drosophila AD model. Methods: Flies overexpressing the human amyloid-β protein precursor and its β-site cleaving enzyme in neurons were randomized to receive four 24-h doses of Lactobacillus paracasei alone (LP), LP-A or sucrose over 14 days. Memory was assessed via an aversive phototaxic suppression assay. Results: Optimal dilution,1:2, was determined based on palatability. LP-A improved memory in trained AD males but worsened cognition in AD females. LP-supplementation experiments confirmed that Ang-(1-7) conferred additional cognitive benefits in males and was responsible for the deleterious cognitive effects in females. Sex-specific differences in the levels of angiotensin peptides and differential activation of the kynurenine pathway of tryptophan metabolism in response to supplementation may underlie this male-only therapeutic response. Conclusion: In summary, LP-A ameliorated the memory deficits of a Drosophila AD model, but effects were sex-specific. Dosage optimization may be required to address this differential response.

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JBPOS0101 attenuates amyloid-β accumulation and memory loss in a mouse model of Alzheimer’s disease

Neuroreport ◽

10.1097/wnr.0000000000001269 ◽

2019 ◽

Vol 30 (10) ◽

pp. 741-747

Author(s):

Hyung Joon Park ◽

Ju Kyong Jang ◽

Yong Moon Choi ◽

Won-Seok Choi

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Mouse Model ◽

Memory Loss ◽

Amyloid Β ◽

Model Of Alzheimer’S Disease

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High‐Fat Diet Modulates Hepatic Amyloid β and Cerebrosterol Metabolism in the Triple Transgenic Mouse Model of Alzheimer’s Disease

Hepatology Communications ◽

10.1002/hep4.1609 ◽

2020 ◽

Author(s):

Cristina R. Bosoi ◽

Milène Vandal ◽

Marine Tournissac ◽

Manon Leclerc ◽

Hortense Fanet ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Mouse Model ◽

Transgenic Mouse ◽

High Fat Diet ◽

Amyloid Β ◽

Transgenic Mouse Model ◽

High Fat ◽

Model Of Alzheimer’S Disease ◽

Triple Transgenic Mouse

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Case of early-onset Alzheimer’s disease with atypical manifestation

General Psychiatry ◽

10.1136/gpsych-2020-100283 ◽

2021 ◽

Vol 34 (1) ◽

pp. e100283

Author(s):

Lin Zhu ◽

Limin Sun ◽

Lin Sun ◽

Shifu Xiao

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Clinical Manifestation ◽

Early Onset ◽

Short Term Memory ◽

Brain Mri ◽

Memory Loss ◽

Amyloid Β ◽

Amyloid Β Protein ◽

Fluent Aphasia

Short-term memory decline is the typical clinical manifestation of Alzheimer’s disease (AD). However, early-onset AD usually has atypical symptoms and may get misdiagnosed. In the present case study, we reported a patient who experienced symptoms of memory loss with progressive non-fluent aphasia accompanied by gradual social withdrawal. He did not meet the diagnostic criteria of AD based on the clinical manifestation and brain MRI. However, his cerebrospinal fluid examination showed a decreased level of beta-amyloid 42, and increased total tau and phosphorylated tau. Massive amyloid β-protein deposition by 11C-Pittsburgh positron emission tomography confirmed the diagnosis of frontal variant AD. This case indicated that early-onset AD may have progressive non-fluent aphasia as the core manifestation. The combination of individual and precision diagnosis would be beneficial for similar cases.

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Gut Microbiota Alterations and Cognitive Impairment Are Sexually Dissociated in a Transgenic Mice Model of Alzheimer’s Disease

Journal of Alzheimer s Disease ◽

10.3233/jad-201367 ◽

2021 ◽

pp. 1-20

Author(s):

Daniel Cuervo-Zanatta ◽

Jaime Garcia-Mena ◽

Claudia Perez-Cruz

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Gut Microbiota ◽

Cognitive Skills ◽

Amyloid Β ◽

Short Chain Fatty Acids ◽

Mice Model ◽

Model Of Alzheimer’S Disease ◽

Cognitive Deficiencies

Background: Normal aging is accompanied by cognitive deficiencies, affecting women and men equally. Aging is the main risk factor for Alzheimer’s disease (AD), with women having a higher risk. The higher prevalence of AD in women is associated with the abrupt hormonal decline seen after menopause. However, other factors may be involved in this sex-related cognitive decline. Alterations in gut microbiota (GM) and its bioproducts have been reported in AD subjects and transgenic (Tg) mice, having a direct impact on brain amyloid-β pathology in male (M), but not in female (F) mice. Objective: The aim of this work was to determine GM composition and cognitive dysfunction in M and F wildtype (WT) and Tg mice, in a sex/genotype segregation design. Methods: Anxiety, short term working-memory, spatial learning, and long-term spatial memory were evaluated in 6-month-old WT and Tg male mice. Fecal short chain fatty acids were determined by chromatography, and DNA sequencing and bioinformatic analyses were used to determine GM differences. Results: We observed sex-dependent differences in cognitive skills in WT mice, favoring F mice. However, the cognitive advantage of females was lost in Tg mice. GM composition showed few sex-related differences in WT mice. Contrary, Tg-M mice presented a more severe dysbiosis than Tg-F mice. A decreased abundance of Ruminococcaceae was associated with cognitive deficits in Tg-F mice, while butyrate levels were positively associated with better working- and object recognition-memory in WT-F mice. Conclusion: This report describes a sex-dependent association between GM alterations and cognitive impairment in a mice model of AD.

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Carboxy-Terminus Tau Protein Hyperphosphorylation is Associated with Extracellular Deposits of Amyloid-β Fibrillary in a Triple-Transgenic Model of Alzheimer’s Disease

Journal of Neurological Disorders ◽

10.4172/2329-6895.1000345 ◽

2017 ◽

Vol 05 (03) ◽

Author(s):

Miguel Angel Ontiveros Torres ◽

Leonel Castellanos Aguilar ◽

Jonathan Lennel Gutierrez Murcia ◽

Nayeli Martinez Zuniga ◽

Paola Flores Rodriguez ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Tau Protein ◽

Amyloid Β ◽

Carboxy Terminus ◽

Transgenic Model ◽

Model Of Alzheimer’S Disease

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GULP1/CED-6 ameliorates amyloid-β toxicity in a Drosophila model of Alzheimer’s disease

Oncotarget ◽

10.18632/oncotarget.20062 ◽

2017 ◽

Vol 8 (59) ◽

pp. 99274-99283 ◽

Cited By ~ 3

Author(s):

Wai Yin Vivien Chiu ◽

Alex Chun Koon ◽

Jacky Chi Ki Ngo ◽

Ho Yin Edwin Chan ◽

Kwok-Fai Lau

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Amyloid Β ◽

Model Of Alzheimer’S Disease ◽

Drosophila Model

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Gestational Stress Augments Postpartum β-Amyloid Pathology and Cognitive Decline in a Mouse Model of Alzheimer’s Disease

Cerebral Cortex ◽

10.1093/cercor/bhy251 ◽

2018 ◽

Vol 29 (9) ◽

pp. 3712-3724 ◽

Cited By ~ 5

Author(s):

Zahra Jafari ◽

Jogender Mehla ◽

Bryan E Kolb ◽

Majid H Mohajerani

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Risk Factor ◽

Cognitive Decline ◽

Noise Exposure ◽

Amyloid Β ◽

Control Group ◽

Plaque Size ◽

Model Of Alzheimer’S Disease ◽

Gestational Stress

Abstract Besides well-known risk factors for Alzheimer’s disease (AD), stress, and in particular noise stress (NS), is a lifestyle risk factor common today. It is known that females are at a significantly greater risk of developing AD than males, and given that stress is a common adversity in females during pregnancy, we hypothesized that gestational noise exposure could exacerbate the postpartum development of the AD-like neuropathological changes during the life span. Pregnant APPNL-G-F/NL-G-F mice were randomly assigned to either the stress condition or control group. The stress group was exposed to the NS on gestational days 12–16, which resulted in a markedly higher hypothalamic–pituitary–adrenal (HPA) axis responsivity during the postpartum stage. Higher amyloid-β (Aβ) deposition and larger Aβ plaque size in the olfactory area were the early onset impacts of the gestational stress (GS) seen at the age of 4 months. This pattern of increased Aβ aggregation and larger plaque size were observed in various brain areas involved in both AD and stress regulation, especially in limbic structures, at the age of 6 months. The GS also produced anxiety-like behavior, deficits in learning and memory, and impaired motor coordination. The findings suggest that environmental stresses during pregnancy pose a potential risk factor in accelerating postpartum cognitive decline and AD-like neuropathological changes in the dams (mothers) later in life.

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