scholarly journals The theory of dove-like particles

2019 ◽  
Author(s):  
zuodong sun
Keyword(s):  
Membrane Potential ◽  
Neurodegenerative Diseases ◽  
Cell Activation ◽  
Amyloid Plaque ◽  
Brain Cell ◽  
Potassium Ion ◽  
Brain Cells ◽  
The Core ◽  
Activation Theory ◽  
First Choice

Objective: Alzheimer's disease (AD) has been reported for more than 100 years since its first discovery in 1906. There has been no significant progress in the study of its real causes and pathogenesis. The viewpoint of this paper is a heuristic viewpoint based on brain cell activation theory under such background. In this paper, the pathogenesis of sporadic AD is discussed at molecular level by applying the principles of cell physics and biology. The purpose of this paper is to harmonize the existing theories of etiology of AD and to solve the source problems that have plagued the research field of neurodegenerative diseases for a long time. Method: 1.Discuss the relationship with the existing hypothesis: the Aβ protein hypothesis, the tau protein hypothesis, the presenilin (PS) hypothesis, the apolipoprotein E (ApoE) hypothesis, the cholinergic hypothesis, the inflammatory hypothesis；2. Demonstration: biophysical proof, medical pathological proof, biological model proof; 3. Interpretation: ion channel and blood-brain barrier, potassium ion and potassium channel, ion pump and epilepsy and cancer, A beta protein and spots and plaques, related AD solutions. Result: 1. Abeta is not the cause of AD, but the late event of AD. 2. The K + concentration difference of 0.00001% which causes the great change of membrane potential is the effective concentration, which can not be neglected. 3. Abnormal impairment of potassium channels and early entry of sodium ions to occupy potassium positions are related to epilepsy, cancer and HeLa cells. 4. AD is a physical disease. especially transcranial magnetoelectricity stimulation, should be the first choice for treatment，which can activate abnormal neurons accurately without interfering with normal neurons. Conclusion: 1.Basic contents: excess cations are transferred from extracellular to intracellular. They compete position with potassium ions on the inner surface of cell membranes, thus abatementing the membrane potential, making action potential unable to activate calcium channels normally, which eventually leads to abnormal apoptosis of brain cells. Amyloid plaque are the remains of abnormal apoptotic brain cells. Amyloid plaque is the aggregation of amyloid spots by van der Waals force and electrostatic attraction, and its interstitium is amyloid protein.Brain cells consist of neurons, microglia and astrocytes in turn. Most of the spotted nuclei in the remains are cations. 2. Solutions: the core viewpoint of this paper can be regarded as exploring the etiology of sporadic AD, it is companion volume of Brain cell activation theory, Brain cell activation theory is an explanation of the treatment methods and mechanism of neurodegenerative diseases such as AD, it is suitable for encephalopathy but not limited to encephalopathy, the solution of AD should start with prevention and treatment, the external factor of prevention is environment, especially heavy metal ions, the internal cause is body acidity and alkalinity, physical means, especially transcranial magnetoelectricity stimulation, should be the first choice for treatment. 3. Naming principles: because of the core point of view in this paper—The position of cation occupying potassium is the initiating factor of AD, so the etiology theory is named Theory of dove-like particles. Take the Chinese idiom "Turtledove occupies the nest of magpies". "turtledove" represents the non-essential cation, "magpie" refers to the effective potassium ion, and "nest" refers to the position of the effective potassium ion.

scholarly journals Study on the cause and pathogenesis of Alzheimer's disease

2019 ◽  
Author(s):  
zuodong sun
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Neurodegenerative Diseases ◽  
Cell Activation ◽  
Amyloid Plaques ◽  
Brain Cell ◽  
Research Field ◽  
Brain Cells ◽  
Sporadic Alzheimer’S Disease ◽  
Long Time

An enlightening viewpoint based on the theory of brain cell activation is to explore the pathogenesis and mechanism of sporadic Alzheimer's disease (AD) at molecular level by applying the principles of cell physics and biology. Its purpose is to coordinate and unify the existing theories of AD etiology and to solve the problems that have puzzled the research field of neurodegenerative diseases for a long time. Basic Contents: Excessive cations are transferred from extracellular to intracellular, and compete with potassium ions on the inner surface of the cell membrane. As a result, the action potential produced can not activate calcium channels normally, leading to abnormal apoptosis of brain cells. Amyloid plaques are the remains of abnormal apoptotic brain cells. Amyloid plaques are aggregated by van der Waals force and electrostatic attraction between amyloid plaques. The interstitium is amyloid protein. Brain cells consist of neurons, microglia and astrocytes in turn. Most of the spotted nuclei in the remains are cations. Applicable but not limited to neurodegenerative diseases such as Alzheimer's disease, physical means should be preferred to solve such diseases.

scholarly journals Hypoxia, Acidification and Inflammation: Partners in Crime in Parkinson’s Disease Pathogenesis?

Immuno ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 78-90
Author(s):  
Johannes Burtscher ◽  
Grégoire P. Millet
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Neurodegenerative Diseases ◽  
Current Knowledge ◽  
Cell Types ◽  
Brain Cell ◽  
Special Focus ◽  
Molecular Alterations ◽  
Research Fields

Like in other neurodegenerative diseases, protein aggregation, mitochondrial dysfunction, oxidative stress and neuroinflammation are hallmarks of Parkinson’s disease (PD). Differentiating characteristics of PD include the central role of α-synuclein in the aggregation pathology, a distinct vulnerability of the striato-nigral system with the related motor symptoms, as well as specific mitochondrial deficits. Which molecular alterations cause neurodegeneration and drive PD pathogenesis is poorly understood. Here, we summarize evidence of the involvement of three interdependent factors in PD and suggest that their interplay is likely a trigger and/or aggravator of PD-related neurodegeneration: hypoxia, acidification and inflammation. We aim to integrate the existing knowledge on the well-established role of inflammation and immunity, the emerging interest in the contribution of hypoxic insults and the rather neglected effects of brain acidification in PD pathogenesis. Their tight association as an important aspect of the disease merits detailed investigation. Consequences of related injuries are discussed in the context of aging and the interaction of different brain cell types, in particular with regard to potential consequences on the vulnerability of dopaminergic neurons in the substantia nigra. A special focus is put on the identification of current knowledge gaps and we emphasize the importance of related insights from other research fields, such as cancer research and immunometabolism, for neurodegeneration research. The highlighted interplay of hypoxia, acidification and inflammation is likely also of relevance for other neurodegenerative diseases, despite disease-specific biochemical and metabolic alterations.

613 HER2-XPAT, a novel protease-activatable prodrug T cell engager (TCE), with potent T-cell activation and efficacy in solid tumors and large predicted safety margins in non-human primate (NHP)

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A649-A649
Author(s):  
Fiore Cattaruzza ◽  
Ayesha Nazeer ◽  
Zachary Lange ◽  
Caitlin Koski ◽  
Mikhail Hammond ◽  
...  
Keyword(s):  
T Cell ◽  
Solid Tumors ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cytokine Production ◽  
Antigenic Specificity ◽  
The Core ◽  
Protease Cleavage ◽  
Safety Margins

BackgroundTCEs are effective in leukemias but have been challenging in solid tumors due to on-target, off-tumor toxicity. Attempts to circumvent CRS include step-up dosing and/or complex designs but are unsuccessful due to toxicity and/or enhanced immunogenicity. HER2-XPAT, or XTENylated Protease-Activated bispecific T-Cell Engager, is a prodrug TCE that exploits the protease activity present in tumors vs. healthy tissue to expand the therapeutic index (TI). The core of the HER2-XPAT (PAT) consists of 2 tandem scFvs targeting CD3 and HER2. Attached to the core, two unstructured polypeptide masks (XTEN) sterically reduce target engagement and extend T1/2. Protease cleavage sites at the base of the XTEN masks enable proteolytic activation of XPATs in the tumor microenvironment, unleashing a potent TCE with short T1/2, further improving the TI. HER2-XPAT, a tumor protease-activatable prodrug with wide safety margins, can co-opt T-cells regardless of antigenic specificity to induce T-cell killing of HER2+ tumors.MethodsPreclinical studies were conducted to characterize the activity of HER2-XPAT, HER2-PAT (cleaved XPAT), and HER2-NonClv (a non-cleavable XPAT) for cytotoxicity in vitro, for anti-tumor efficacy in xenograft models, and for safety in NHPs.ResultsHER2-PAT demonstrated potent in vitro T-cell cytotoxicity (EC50 1-2pM) and target-dependent T-cell activation and cytokine production by hPBMCs. HER2-XPAT provided up to 14,000-fold protection against killing of HER2 tumor cells and no cytotoxicity against cardiomyocytes up to 1uM. In vivo, HER2-XPAT induced complete tumor regressions in BT-474 tumors with equimolar dosing to HER2-PAT, whereas HER2-NonClv had no efficacy, supporting requirement of protease cleavage for T-cell activity. In NHP, HER2-XPAT has been dose-escalated safely up to 42mg/kg (MTD). HER2-XPAT demonstrated early T-cell margination at 2 mg/kg but largely spared CRS, cytokine production, and tissue toxicity up to 42 mg/kg. PK profiles of HER2-XPAT and HER2-NonClv were comparable, consistent with ex vivo stability for cleavage when incubated in cancer pts plasma for 7 days at 37°C. HER2-PAT by continuous infusion induced lethal CRS and cytokine spikes at 0.3 mg/kg/d but was tolerated at 0.25 mg/kg/d, providing HER2-XPAT with >1300-fold protection in tolerability vs. HER2-PAT, >4 logs over cytotoxicity EC50s for HER2 cell lines, and a 20-fold safety margin over the dose required for pharmacodynamic activity.ConclusionsHER2-XPAT is a potent prodrug TCE with no CRS and a wide TI based on NHPs. With XTEN’s clinical data demonstrating low immunogenicity, the XPATs are a promising solution. IND studies are ongoing. Additional PK/PD, cytokines, safety, and efficacy data will be presented.

scholarly journals Effect of Water and Ethanol Extracts from Hericium erinaceus Solid-State Fermented Wheat Product on the Protection and Repair of Brain Cells in Zebrafish Embryos

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3297
Author(s):  
Shun-Kuo Sun ◽  
Chun-Yi Ho ◽  
Wei-Yang Yen ◽  
Su-Der Chen
Keyword(s):  
Solid State ◽  
Brain Cell ◽  
Hot Water ◽  
Raw Material ◽  
Brain Cells ◽  
Zebrafish Embryos ◽  
Hericium Erinaceus ◽  
Water Extracts ◽  
The Brain ◽  
Wheat Product

Extracts from Hericium erinaceus can cause neural cells to produce nerve growth factor (NGF) and protect against neuron death. The objective of this study was to evaluate the effects of ethanol and hot water extracts from H. erinaceus solid-state fermented wheat product on the brain cells of zebrafish embryos in both pre-dosing protection mode and post-dosing repair mode. The results showed that 1% ethanol could effectively promote zebrafish embryo brain cell death. Both 200 ppm of ethanol and water extracts from H. erinaceus solid-state fermented wheat product protected brain cells and significantly reduced the death of brain cells caused by 1% ethanol treatment in zebrafish. Moreover, the zebrafish embryos were immersed in 1% ethanol for 4 h to cause brain cell damage and were then transferred and soaked in the 200 ppm of ethanol and water extracts from H. erinaceus solid-state fermented wheat product to restore the brain cells damaged by the 1% ethanol. However, the 200 ppm extracts from the unfermented wheat medium had no protective and repairing effects. Moreover, 200 ppm of ethanol and water extracts from H. erinaceus fruiting body had less significant protective and restorative effects on the brain cells of zebrafish embryos. Both the ethanol and hot water extracts from H. erinaceus solid-state fermented wheat product could protect and repair the brain cells of zebrafish embryos damaged by 1% ethanol. Therefore, it has great potential as a raw material for neuroprotective health product.

Brain-Protective Mechanisms of Transcription Factor NRF2: Toward a Common Strategy for Neurodegenerative Diseases

2021 ◽  
Vol 62 (1) ◽  
Author(s):  
Antonio Cuadrado
Keyword(s):  
Transcription Factor ◽  
Neurodegenerative Diseases ◽  
Brain Cell ◽  
Current Status ◽  
Annual Review ◽  
Publication Date ◽  
Related Factor ◽  
Protective Mechanisms ◽  
Cell Functions ◽  
Pass Through

Neurodegenerative diseases are characterized by the loss of homeostatic functions that control redox and energy metabolism, neuroinflammation, and proteostasis. The transcription factor nuclear factor erythroid 2–related factor 2 (NRF2) is a master controller of these functions, and its overall activity is compromised during aging and in these diseases. However, NRF2 can be activated pharmacologically and is now being considered a common therapeutic target. Many gaps still exist in our knowledge of the specific role that NRF2 plays in specialized brain cell functions or how these cells respond to the hallmarks of these diseases. This review discusses the relevance of NRF2 to several hallmark features of neurodegenerative diseases and the current status of pharmacological activators that might pass through the blood-brain barrier and provide a disease-modifying effect. Expected final online publication date for the Annual Review of Pharmacology and Toxicology, Volume 62 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

scholarly journals In Vivo Neocortical [K]o Modulation by Targeted Stimulation of Astrocytes

2021 ◽  
Vol 22 (16) ◽  
pp. 8658
Author(s):  
Azin EbrahimAmini ◽  
Shanthini Mylvaganam ◽  
Paolo Bazzigaluppi ◽  
Mohamad Khazaei ◽  
Alexander Velumian ◽  
...  
Keyword(s):  
Nervous System ◽  
Membrane Potential ◽  
Potassium Ion ◽  
Ion Concentration ◽  
Extracellular Potassium ◽  
Spreading Depolarization ◽  
Potential Tool ◽  
Stimulation Of

A normally functioning nervous system requires normal extracellular potassium ion concentration ([K]o). Throughout the nervous system, several processes, including those of an astrocytic nature, are involved in [K]o regulation. In this study we investigated the effect of astrocytic photostimulation on [K]o. We hypothesized that in vivo photostimulation of eNpHR-expressing astrocytes leads to a decreased [K]o. Using optogenetic and electrophysiological techniques we showed that stimulation of eNpHR-expressing astrocytes resulted in a significantly decreased resting [K]o and evoked K responses. The amplitude of the concomitant spreading depolarization-like events also decreased. Our results imply that astrocytic membrane potential modification could be a potential tool for adjusting the [K]o.

Vps13D functions in a Pink1-dependent and Parkin-independent mitophagy pathway

2021 ◽  
Vol 220 (11) ◽  
Author(s):  
James L. Shen ◽  
Tina M. Fortier ◽  
Ruoxi Wang ◽  
Eric H. Baehrecke
Keyword(s):  
Neurodegenerative Diseases ◽  
Ubiquitin Ligase ◽  
E3 Ubiquitin Ligase ◽  
Mitochondrial Morphology ◽  
The Core ◽  
Mitochondrial Defects ◽  
Mutant Cells

Defects in autophagy cause problems in metabolism, development, and disease. The autophagic clearance of mitochondria, mitophagy, is impaired by the loss of Vps13D. Here, we discover that Vps13D regulates mitophagy in a pathway that depends on the core autophagy machinery by regulating Atg8a and ubiquitin localization. This process is Pink1 dependent, with loss of pink1 having similar autophagy and mitochondrial defects as loss of vps13d. The role of Pink1 has largely been studied in tandem with Park/Parkin, an E3 ubiquitin ligase that is widely considered to be crucial in Pink1-dependent mitophagy. Surprisingly, we find that loss of park does not exhibit the same autophagy and mitochondrial deficiencies as vps13d and pink1 mutant cells and contributes to mitochondrial clearance through a pathway that is parallel to vps13d. These findings provide a Park-independent pathway for Pink1-regulated mitophagy and help to explain how Vps13D regulates autophagy and mitochondrial morphology and contributes to neurodegenerative diseases.

scholarly journals Mitochondrial Dysfunctions: A Red Thread across Neurodegenerative Diseases

2020 ◽  
Vol 21 (10) ◽  
pp. 3719 ◽  
Author(s):  
Serena Stanga ◽  
Anna Caretto ◽  
Marina Boido ◽  
Alessandro Vercelli
Keyword(s):  
Neurodegenerative Diseases ◽  
Neuronal Degeneration ◽  
Muscular Atrophy ◽  
Early Event ◽  
Mitochondrial Dysfunctions ◽  
The Core ◽  
Optimal Functioning ◽  
Mitochondrial Functions ◽  
Lateral Sclerosis ◽  
Common Target

Mitochondria play a central role in a plethora of processes related to the maintenance of cellular homeostasis and genomic integrity. They contribute to preserving the optimal functioning of cells and protecting them from potential DNA damage which could result in mutations and disease. However, perturbations of the system due to senescence or environmental factors induce alterations of the physiological balance and lead to the impairment of mitochondrial functions. After the description of the crucial roles of mitochondria for cell survival and activity, the core of this review focuses on the “mitochondrial switch” which occurs at the onset of neuronal degeneration. We dissect the pathways related to mitochondrial dysfunctions which are shared among the most frequent or disabling neurodegenerative diseases such as Alzheimer’s, Parkinson’s, and Huntington’s, Amyotrophic Lateral Sclerosis, and Spinal Muscular Atrophy. Can mitochondrial dysfunctions (affecting their morphology and activities) represent the early event eliciting the shift towards pathological neurobiological processes? Can mitochondria represent a common target against neurodegeneration? We also review here the drugs that target mitochondria in neurodegenerative diseases.

scholarly journals Periodic Membrane Potential and Ca2+ Oscillations in T Cells Forming an Immune Synapse

2020 ◽  
Vol 21 (5) ◽  
pp. 1568 ◽  
Author(s):  
Ferenc Papp ◽  
Peter Hajdu ◽  
Gabor Tajti ◽  
Agnes Toth ◽  
Eva Nagy ◽  
...  
Keyword(s):  
T Cells ◽  
Membrane Potential ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Calcium Release ◽  
Immunological Synapse ◽  
Level Control ◽  
Potential Oscillations ◽  
Immune Synapse

The immunological synapse (IS) is a specialized contact area formed between a T cell and an antigen presenting cell (APC). Besides molecules directly involved in antigen recognition such as the TCR/CD3 complex, ion channels important in the membrane potential and intracellular free Ca2+ concentration control of T cells are also recruited into the IS. These are the voltage-gated Kv1.3 and Ca2+-activated KCa3.1 K+ channels and the calcium release-activated Ca2+ channel (CRAC). However, the consequence of this recruitment on membrane potential and Ca2+ level control is not known. Here we demonstrate that the membrane potential (MP) of murine T cells conjugated with APCs in an IS shows characteristic oscillations. We found that depolarization of the membrane by current injection or by increased extracellular K+ concentration produced membrane potential oscillations (MPO) significantly more frequently in conjugated T cells than in lone T cells. Furthermore, oscillation of the free intracellular Ca2+ concentration could also be observed more frequently in cells forming an IS than in lone cells. We suggest that in the IS the special arrangement of channels and the constrained space between the interacting cells creates a favorable environment for these oscillations, which may enhance the signaling process leading to T cell activation.

Sign in / Sign up

Export Citation Format

Share Document