Detection and Functional Evaluation of the P2X7 Receptor in hiPSC Derived Neurons and Microglia-Like Cells

A large body of evidence suggests the involvement of the ATP-gated purinergic receptor P2X7 (P2X7R) in neurodegenerative diseases, including Alzheimer’s disease. While it is well-described to be present and functional on microglia cells contributing to inflammatory responses, some reports suggest a neuronal expression of the receptor as well. Here, we present experimental results showing P2X7 receptors to be expressed on human hiPSC-derived microglia-like cells, hiPSC-derived neuronal progenitors and hiPSC-derived matured neuronal cells. By applying cell surface protein detection assays, we show that P2X7R is not localized on the cell membrane, despite being detected in neuronal cells and thus may not be available for directly mediating neurotoxicity. On hiPSC-derived microglia-like cells, a clear membranous expression was detected. Additionally, we have not observed differences in P2X7R functions between control and familial Alzheimer’s disease patient-derived neuronal cells. Functional assays employing a P2X7R antagonist JNJ 47965567 confirm these findings by showing P2X7R-dependent modulation of microglia-like cells viability upon treatment with P2X7R agonists ATP and BzATP, while the same effect was absent from neuronal cells. Since the majority of P2X7R research was done on rodent models, our work on human hiPSC-derived cells presents a valuable contribution to the field, extending the work on animal models to the human cellular system and toward clinical translation.

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Faculty Opinions recommendation of Direct Conversion of Normal and Alzheimer's Disease Human Fibroblasts into Neuronal Cells by Small Molecules.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.725705453.793509280 ◽

2015 ◽

Author(s):

Vijay Tiwari ◽

Johannes Jung

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Small Molecules ◽

Human Fibroblasts ◽

Neuronal Cells ◽

Direct Conversion

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Crosstalk between Gut and Brain in Alzheimer’s Disease: The Role of Gut Microbiota Modulation Strategies

Nutrients ◽

10.3390/nu13020690 ◽

2021 ◽

Vol 13 (2) ◽

pp. 690

Author(s):

Umair Shabbir ◽

Muhammad Sajid Arshad ◽

Aysha Sameen ◽

Deog-Hwan Oh

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Gut Microbiota ◽

Dietary Habits ◽

Inflammatory Responses ◽

Fecal Microbiota Transplantation ◽

Fecal Microbiota ◽

Gut Dysbiosis ◽

Dynamic Population

The gut microbiota (GM) represents a diverse and dynamic population of microorganisms and about 100 trillion symbiotic microbial cells that dwell in the gastrointestinal tract. Studies suggest that the GM can influence the health of the host, and several factors can modify the GM composition, such as diet, drug intake, lifestyle, and geographical locations. Gut dysbiosis can affect brain immune homeostasis through the microbiota–gut–brain axis and can play a key role in the pathogenesis of neurodegenerative diseases, including dementia and Alzheimer’s disease (AD). The relationship between gut dysbiosis and AD is still elusive, but emerging evidence suggests that it can enhance the secretion of lipopolysaccharides and amyloids that may disturb intestinal permeability and the blood–brain barrier. In addition, it can promote the hallmarks of AD, such as oxidative stress, neuroinflammation, amyloid-beta formation, insulin resistance, and ultimately the causation of neural death. Poor dietary habits and aging, along with inflammatory responses due to dysbiosis, may contribute to the pathogenesis of AD. Thus, GM modulation through diet, probiotics, or fecal microbiota transplantation could represent potential therapeutics in AD. In this review, we discuss the role of GM dysbiosis in AD and potential therapeutic strategies to modulate GM in AD.

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NLRP3 Inflammasome: A Starring Role in Amyloid-β- and Tau-Driven Pathological Events in Alzheimer’s Disease

Journal of Alzheimer s Disease ◽

10.3233/jad-210268 ◽

2021 ◽

pp. 1-22

Author(s):

Mariana Van Zeller ◽

Diogo M. Dias ◽

Ana M. Sebastião ◽

Cláudia A. Valente

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Glial Cells ◽

Neurofibrillary Tangles ◽

Nlrp3 Inflammasome ◽

Neuronal Death ◽

Inflammatory Responses ◽

Senile Plaques ◽

Amyloid Β ◽

Wide Range

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disease commonly diagnosed among the elderly population. AD is characterized by the loss of synaptic connections, neuronal death, and progressive cognitive impairment, attributed to the extracellular accumulation of senile plaques, composed by insoluble aggregates of amyloid-β (Aβ) peptides, and to the intraneuronal formation of neurofibrillary tangles shaped by hyperphosphorylated filaments of the microtubule-associated protein tau. However, evidence showed that chronic inflammatory responses, with long-lasting exacerbated release of proinflammatory cytokines by reactive glial cells, contribute to the pathophysiology of the disease. NLRP3 inflammasome (NLRP3), a cytosolic multiprotein complex sensor of a wide range of stimuli, was implicated in multiple neurological diseases, including AD. Herein, we review the most recent findings regarding the involvement of NLRP3 in the pathogenesis of AD. We address the mechanisms of NLRP3 priming and activation in glial cells by Aβ species and the potential role of neurofibrillary tangles and extracellular vesicles in disease progression. Neuronal death by NLRP3-mediated pyroptosis, driven by the interneuronal tau propagation, is also discussed. We present considerable evidence to claim that NLRP3 inhibition, is undoubtfully a potential therapeutic strategy for AD.

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Metabolic Profiling of Suprachiasmatic Nucleus Reveals Multifaceted Effects in an Alzheimer’s Disease Mouse Model

Journal of Alzheimer s Disease ◽

10.3233/jad-201575 ◽

2021 ◽

pp. 1-12

Author(s):

Muhamed N.H. Eeza ◽

Rico Singer ◽

Corinna Höfling ◽

Jörg Matysik ◽

Huub J.M. de Groot ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Mouse Model ◽

Metabolic Profiling ◽

Inflammatory Responses ◽

Immunohistochemical Analysis ◽

Magic Angle Spinning ◽

Tg2576 Mouse ◽

Magic Angle ◽

Gaba Production

Background: Circadian rhythm disturbance is commonly observed in Alzheimer’s disease (AD). In mammals, these rhythms are orchestrated by the superchiasmatic nucleus (SCN). Our previous study in the Tg2576 AD mouse model suggests that inflammatory responses, most likely manifested by low GABA production, may be one of the underlying perpetrators for the changes in circadian rhythmicity and sleep disturbance in AD. However, the mechanistic connections between SCN dysfunction, GABA modulation, and inflammation in AD is not fully understood. Objective: To reveal influences of amyloid pathology in Tg2576 mouse brain on metabolism in SCN and to identify key metabolic sensors that couple SCN dysfunction with GABA modulation and inflammation. Methods: High resolution magic angle spinning (HR-MAS) NMR in conjunction with multivariate analysis was applied for metabolic profiling in SCN of control and Tg2576 female mice. Immunohistochemical analysis was used to detect neurons, astrocytes, expression of GABA transporter 1 (GAT1) and Bmal1. Results: Metabolic profiling revealed significant metabolic deficits in SCN of Tg2576 mice. Reductions in glucose, glutamate, GABA, and glutamine provide hints toward an impaired GABAergic glucose oxidation and neurotransmitter cycling in SCN of AD mice. In addition, decreased redox co-factor NADPH and glutathione support a redox disbalance. Immunohistochemical examinations showed low expression of the core clock gene, Bmal1, especially in activated astrocytes. Moreover, decreased expression of GAT1 in astrocytes indicates low GABA recycling in this cell type. Conclusion: Our results suggest that redox disbalance and compromised GABA signaling are important denominators and connectors between neuroinflammation and clock dysfunction in AD.

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Astrocytes and neuroinflammation in Alzheimer's disease

Biochemical Society Transactions ◽

10.1042/bst20140155 ◽

2014 ◽

Vol 42 (5) ◽

pp. 1321-1325 ◽

Cited By ~ 47

Author(s):

Emma C. Phillips ◽

Cara L. Croft ◽

Ksenia Kurbatskaya ◽

Michael J. O’Neill ◽

Michael L. Hutton ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Inflammatory Responses ◽

Amyloid Β ◽

Synaptic Dysfunction ◽

Amyloid Β Peptide ◽

Substantial Evidence ◽

Models Of Disease ◽

Opposing Effects

Increased production of amyloid β-peptide (Aβ) and altered processing of tau in Alzheimer's disease (AD) are associated with synaptic dysfunction, neuronal death and cognitive and behavioural deficits. Neuroinflammation is also a prominent feature of AD brain and considerable evidence indicates that inflammatory events play a significant role in modulating the progression of AD. The role of microglia in AD inflammation has long been acknowledged. Substantial evidence now demonstrates that astrocyte-mediated inflammatory responses also influence pathology development, synapse health and neurodegeneration in AD. Several anti-inflammatory therapies targeting astrocytes show significant benefit in models of disease, particularly with respect to tau-associated neurodegeneration. However, the effectiveness of these approaches is complex, since modulating inflammatory pathways often has opposing effects on the development of tau and amyloid pathology, and is dependent on the precise phenotype and activities of astrocytes in different cellular environments. An increased understanding of interactions between astrocytes and neurons under different conditions is required for the development of safe and effective astrocyte-based therapies for AD and related neurodegenerative diseases.

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Anti-Inflammatory Agents: An Approach to Prevent Cognitive Decline in Alzheimer’s Disease

Journal of Alzheimer s Disease ◽

10.3233/jad-215125 ◽

2021 ◽

pp. 1-16

Author(s):

Staley A. Brod

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Clinical Trial ◽

Cognitive Decline ◽

Immune Cell ◽

Inflammatory Responses ◽

Type I ◽

Type I Ifn ◽

Anti Inflammatory

Systemic inflammation is an organism’s response to an assault by the non-self. However, that inflammation may predispose humans to illnesses targeted to organs, including Alzheimer’s disease (AD). Lesions in AD have pro-inflammatory cytokines and activated microglial/monocyte/macrophage cells. Up to this point, clinical trials using anti-amyloid monoclonal antibodies have not shown success. Maybe it is time to look elsewhere by combating inflammation. Neuroinflammation with CNS cellular activation and excessive expression of immune cytokines is suspected as the “principal culprit” in the higher risk for sporadic AD. Microglia, the resident immune cell of the CNS, perivascular myeloid cells, and activated macrophages produce IL-1, IL-6 at higher levels in patients with AD. Anti-inflammatory measures that target cellular/cytokine-mediated damage provide a rational therapeutic strategy. We propose a clinical trial using oral type 1 IFNs to act as such an agent; one that decreases IL-1 and IL-6 secretion by activating lamina propria lymphocytes in the gut associated lymphoid tissue with subsequent migration to the brain undergoing inflammatory responses. A clinical trial would be double-blind, parallel 1-year clinical trial randomized 1 : 1 oral active type 1 IFN versus best medical therapy to determine whether ingested type I IFN would decrease the rate of cognitive decline in mild cognitive impairment or mild AD. Using cognitive psychometrics, imaging, and fluid biomarkers (MxA for effective type I IFN activity beyond the gut), we can determine if oral type I IFN can prevent cognitive decline in AD.

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Prevalência, desempenho cognitivo e funcionalidade de idosos com Doença de Alzheimer em instituições de longa permanência de Bento Gonçalves

PAJAR - Pan-American Journal of Aging Research ◽

10.15448/2357-9641.2017.1.26051 ◽

2017 ◽

Vol 5 (1) ◽

pp. 23 ◽

Cited By ~ 2

Author(s):

Daniela Fernandes Tonholi ◽

Gisele Oltramari

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Performance ◽

Junior High School ◽

Functional Independence Measure ◽

The Elderly ◽

Functional Independence ◽

Cross Sectional Study ◽

Functional Evaluation ◽

Cross Sectional

Aims: To determine the prevalence, cognitive performance and functionality of elderly people with Alzheimer's disease in long-stay institutions for the elderlyin the city of Bento Gonçalves. Methods: Cross-sectional study including 24 elderly residents in long-stay institutions for the elderly, sociodemographic datawere obtained, and the elderly were subjected to functional evaluation by the Functional Independence Measure and evaluation of cognitive performancethrough the mental state the Mini (MMSE). Results: Most of the residents were female (83%), as 54.2% schooling had completed junior high school, mostof the elderly (70.8%) was admitted by the will of the family, 100% of the elderly showed cognitive performance bad, and the smaller the more dependentcognitive performance was the individual. Conclusion: institutionalized elderly with Alzheimer's disease had negative results on cognitive performance,as well as deficits in their ability to perform activities of daily living, thus altering their functionality.Keywords: aging; functionality; cognition; Alzheimer Disease; long-stay institutions.

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