Microtubule-modulating agents in the fight against neurodegeneration: Will it ever work?

2021 ◽  
Vol 19 ◽  
Author(s):  
Ahmed Soliman ◽  
Lidia Bakota ◽  
Roland Brandt
Keyword(s):  
Neurodegenerative Diseases ◽  
Posttranslational Modifications ◽  
Drug Target ◽  
Neuronal Cell ◽  
Cell Types ◽  
Transport Processes ◽  
Microtubule Stability ◽  
Age Related ◽  
Neuroprotective Strategy ◽  
Structural Determinant

: The microtubule skeleton plays an essential role in nerve cells as the most important structural determinant of morphology and as a highway for axonal transport processes. Many neurodegenerative diseases are characterized by changes in the structure and organization of microtubules and microtubule-regulating proteins such as the microtubule-associated protein tau, which exhibits characteristic changes in a whole class of diseases collectively referred to as tauopathies. Changes in the dynamics of microtubules appear to occur early under neurodegenerative conditions and are also likely to contribute to age-related dysfunction of neurons. Thus, modulating microtubule dynamics and correcting impaired microtubule stability can be a useful neuroprotective strategy to counteract disruption of the microtubule system in disease and aging. In this article, we review current microtubule-directed approaches for the treatment of neurodegenerative diseases with microtubules as drug target, tau as drug target, and posttranslational modifications as potential modifiers of the microtubule system. We discuss limitations of the approaches that can be traced back to the rather unspecific mechanism of action, which causes undesirable side effects on non-neuronal cell types or which are due to the disruption of non-microtubule-related interactions. We also develop some thoughts on how the specificity of the approaches can be improved and what further targets could be used for modulating substances.

The proteasome and epigenetics: zooming in on histone modifications

2016 ◽  
Vol 7 (4) ◽  
pp. 215-227 ◽  
Author(s):  
Svitlana V. Bach ◽  
Ashok N. Hegde
Keyword(s):  
Synaptic Plasticity ◽  
Chromatin Remodeling ◽  
Histone Modifications ◽  
Posttranslational Modifications ◽  
Target Genes ◽  
Neuronal Cell ◽  
Cell Types ◽  
Experimental Models ◽  
Histone Acetyltransferases ◽  
Ubiquitin Proteasome

AbstractThe proteasome is a structural complex of many proteins that degrades substrates marked by covalent linkage to ubiquitin. Many years of research has shown a role for ubiquitin-proteasome-mediated proteolysis in synaptic plasticity and memory mainly in degrading synaptic, cytoplasmic and nuclear proteins. Recent work indicates that the proteasome has wider proteolytic and non-proteolytic roles in processes such as histone modifications that affect synaptic plasticity and memory. In this review, we assess the evidence gathered from neuronal as well as non-neuronal cell types regarding the function of the proteasome in positive or negative regulation of posttranslational modifications of histones, such as acetylation, methylation and ubiquitination. We discuss the critical roles of the proteasome in clearing excess histone proteins in various cellular contexts and the possible non-proteolytic functions in regulating transcription of target genes. In addition, we summarize the current literature on diverse chromatin-remodeling machineries, such as histone acetyltransferases, deacetylates, methyltransferases and demethylases, as targets for proteasomal degradation across experimental models. Lastly, we provide a perspective on how proteasomal regulation of histone modifications may modulate synaptic plasticity in the nervous system.

scholarly journals Role of Mitochondria in Neurodegenerative Diseases: Mitochondria as a Therapeutic Target in Alzheimer's Disease

CNS Spectrums ◽  
2009 ◽  
Vol 14 (S7) ◽  
pp. 8-13 ◽  
Author(s):  
P. Hemachandra Reddy
Keyword(s):  
Alzheimer’S Disease ◽  
Parkinson’S Disease ◽  
Alzheimer's Disease ◽  
Parkinson's Disease ◽  
Cell Death ◽  
Neurodegenerative Diseases ◽  
Disease Progression ◽  
Neuronal Cell ◽  
Causal Factors ◽  
Age Related

A growing body of evidence suggests that mitochondrial abnormalities are involved in aging and in age-related neurodegenerative diseases as well as cancer, diabetes, and several other diseases known to be affected by mitochondria. Causal factors for most age-related neurodegenerative diseases—including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), and Friedrich ataxia (FRDA)—are largely unknown. Genetic defects are reported to cause a small number of neurodegenerative diseases (Slide 1), but cellular, molecular, and pathological mechanisms of disease progression and selective neuronal cell death are not understood fully in these diseases. However, based on several cellular, molecular, and animal model studies of Alzheimer's disease, Parkinson's disease, ALS, FRDA, cancer, and diabetes, aging may play a large role in cell death in these diseases. Age-dependent, mitochondrially-generated reactive oxygen species (ROS) have been identified as important factors responsible for disease progression and cell death, particularly in late-onset diseases, in which genetic mutations are not causal factors.

scholarly journals Single-nucleus transcriptomic landscape of primate hippocampal aging

2021 ◽  
Author(s):  
Hui Zhang ◽  
Jiaming Li ◽  
Jie Ren ◽  
Shuhui Sun ◽  
Shuai Ma ◽  
...  
Keyword(s):  
Neurodegenerative Diseases ◽  
Inflammatory Responses ◽  
Cell Types ◽  
Therapeutic Interventions ◽  
Aging Effects ◽  
Neuronal Function ◽  
Diagnostic Biomarkers ◽  
Age Related ◽  
Gene Expression Dynamics ◽  
Single Nucleus

AbstractThe hippocampus plays a crucial role in learning and memory, and its progressive deterioration with age is functionally linked to a variety of human neurodegenerative diseases. Yet a systematic profiling of the aging effects on various hippocampal cell types in primates is still missing. Here, we reported a variety of new aging-associated phenotypic changes of the primate hippocampus. These include, in particular, increased DNA damage and heterochromatin erosion with time, alongside loss of proteostasis and elevated inflammation. To understand their cellular and molecular causes, we established the first single-nucleus transcriptomic atlas of primate hippocampal aging. Among the 12 identified cell types, neural transiently amplifying progenitor cell (TAPC) and microglia were most affected by aging. In-depth dissection of gene-expression dynamics revealed impaired TAPC division and compromised neuronal function along the neurogenesis trajectory; additionally elevated pro-inflammatory responses in the aged microglia and oligodendrocyte, as well as dysregulated coagulation pathways in the aged endothelial cells may contribute to a hostile microenvironment for neurogenesis. This rich resource for understanding primate hippocampal aging may provide potential diagnostic biomarkers and therapeutic interventions against age-related neurodegenerative diseases.

scholarly journals The NRF2-Dependent Transcriptional Regulation of Antioxidant Defense Pathways: Relevance for Cell Type-Specific Vulnerability to Neurodegeneration and Therapeutic Intervention

Antioxidants ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 8
Author(s):  
Stephanie M. Boas ◽  
Kathlene L. Joyce ◽  
Rita M. Cowell
Keyword(s):  
Oxidative Stress ◽  
Nervous System ◽  
Neurodegenerative Diseases ◽  
Cellular Localization ◽  
Family Members ◽  
Neuronal Cell ◽  
Cell Types ◽  
Antioxidant Defenses ◽  
Cell Type Specific ◽  
Specific Vulnerability

Oxidative stress has been implicated in the etiology and pathobiology of various neurodegenerative diseases. At baseline, the cells of the nervous system have the capability to regulate the genes for antioxidant defenses by engaging nuclear factor erythroid 2 (NFE2/NRF)-dependent transcriptional mechanisms, and a number of strategies have been proposed to activate these pathways to promote neuroprotection. Here, we briefly review the biology of the transcription factors of the NFE2/NRF family in the brain and provide evidence for the differential cellular localization of NFE2/NRF family members in the cells of the nervous system. We then discuss these findings in the context of the oxidative stress observed in two neurodegenerative diseases, Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS), and present current strategies for activating NFE2/NRF-dependent transcription. Based on the expression of the NFE2/NRF family members in restricted populations of neurons and glia, we propose that, when designing strategies to engage these pathways for neuroprotection, the relative contributions of neuronal and non-neuronal cell types to the overall oxidative state of tissue should be considered, as well as the cell types which have the greatest intrinsic capacity for producing antioxidant enzymes.

scholarly journals Ocular Neurodegenerative Diseases: Interconnection between Retina and Cortical Areas

Cells ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2394
Author(s):  
Nicoletta Marchesi ◽  
Foroogh Fahmideh ◽  
Federica Boschi ◽  
Alessia Pascale ◽  
Annalisa Barbieri
Keyword(s):  
Neurodegenerative Diseases ◽  
Light Stimulus ◽  
The Elderly ◽  
Cell Types ◽  
Age Related Macular Degeneration ◽  
Age Related ◽  
Ocular Disorders ◽  
Progressive Neurodegeneration ◽  
Underlying Mechanisms ◽  
The Brain

The possible interconnection between the eye and central nervous system (CNS) has been a topic of discussion for several years just based on fact that the eye is properly considered an extension of the brain. Both organs consist of neurons and derived from a neural tube. The visual process involves photoreceptors that receive light stimulus from the external environment and send it to retinal ganglionic cells (RGC), one of the cell types of which the retina is composed. The retina, the internal visual membrane of the eye, processes the visual stimuli in electric stimuli to transfer it to the brain, through the optic nerve. Retinal chronic progressive neurodegeneration, which may occur among the elderly, can lead to different disorders of the eye such as glaucoma, age-related macular degeneration (AMD), and diabetic retinopathy (DR). Mainly in the elderly population, but also among younger people, such ocular pathologies are the cause of irreversible blindness or impaired, reduced vision. Typical neurodegenerative diseases of the CSN are a group of pathologies with common characteristics and etiology not fully understood; some risk factors have been identified, but they are not enough to justify all the cases observed. Furthermore, several studies have shown that also ocular disorders present characteristics of neurodegenerative diseases and, on the other hand, CNS pathologies, i.e., Alzheimer disease (AD) and Parkinson disease (PD), which are causes of morbidity and mortality worldwide, show peculiar alterations at the ocular level. The knowledge of possible correlations could help to understand the mechanisms of onset. Moreover, the underlying mechanisms of these heterogeneous disorders are still debated. This review discusses the characteristics of the ocular illnesses, focusing on the relationship between the eye and the brain. A better comprehension could help in future new therapies, thus reducing or avoiding loss of vision and improve quality of life.

scholarly journals Non-Coding RNAs as Sensors of Oxidative Stress in Neurodegenerative Diseases

Antioxidants ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1095
Author(s):  
Ana Gámez-Valero ◽  
Anna Guisado-Corcoll ◽  
Marina Herrero-Lorenzo ◽  
Maria Solaguren-Beascoa ◽  
Eulàlia Martí
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Nervous System ◽  
Neurodegenerative Diseases ◽  
Reactive Oxygen ◽  
Cell Types ◽  
Normal Function ◽  
Brain Cell ◽  
Oxygen Species ◽  
Age Related

Oxidative stress (OS) results from an imbalance between the production of reactive oxygen species and the cellular antioxidant capacity. OS plays a central role in neurodegenerative diseases, where the progressive accumulation of reactive oxygen species induces mitochondrial dysfunction, protein aggregation and inflammation. Regulatory non-protein-coding RNAs (ncRNAs) are essential transcriptional and post-transcriptional gene expression controllers, showing a highly regulated expression in space (cell types), time (developmental and ageing processes) and response to specific stimuli. These dynamic changes shape signaling pathways that are critical for the developmental processes of the nervous system and brain cell homeostasis. Diverse classes of ncRNAs have been involved in the cell response to OS and have been targeted in therapeutic designs. The perturbed expression of ncRNAs has been shown in human neurodegenerative diseases, with these changes contributing to pathogenic mechanisms, including OS and associated toxicity. In the present review, we summarize existing literature linking OS, neurodegeneration and ncRNA function. We provide evidences for the central role of OS in age-related neurodegenerative conditions, recapitulating the main types of regulatory ncRNAs with roles in the normal function of the nervous system and summarizing up-to-date information on ncRNA deregulation with a direct impact on OS associated with major neurodegenerative conditions.

scholarly journals Autophagy regulation by acetylation—implications for neurodegenerative diseases

2021 ◽  
Vol 53 (1) ◽  
pp. 30-41
Author(s):  
Sung Min Son ◽  
So Jung Park ◽  
Marian Fernandez-Estevez ◽  
David C. Rubinsztein
Keyword(s):  
Neurodegenerative Diseases ◽  
Posttranslational Modifications ◽  
Molecular Mechanisms ◽  
Membrane Vesicles ◽  
Cell Types ◽  
Double Membrane ◽  
Physiological Processes ◽  
Evolutionarily Conserved ◽  
Development And Aging ◽  
Catabolic Process

AbstractPosttranslational modifications of proteins, such as acetylation, are essential for the regulation of diverse physiological processes, including metabolism, development and aging. Autophagy is an evolutionarily conserved catabolic process that involves the highly regulated sequestration of intracytoplasmic contents in double-membrane vesicles called autophagosomes, which are subsequently degraded after fusing with lysosomes. The roles and mechanisms of acetylation in autophagy control have emerged only in the last few years. In this review, we describe key molecular mechanisms by which previously identified acetyltransferases and deacetylases regulate autophagy. We highlight how p300 acetyltransferase controls mTORC1 activity to regulate autophagy under starvation and refeeding conditions in many cell types. Finally, we discuss how altered acetylation may impact various neurodegenerative diseases in which many of the causative proteins are autophagy substrates. These studies highlight some of the complexities that may need to be considered by anyone aiming to perturb acetylation under these conditions.

Autophagy and ageing: implications for age-related neurodegenerative diseases

2013 ◽  
Vol 55 ◽  
pp. 119-131 ◽  
Author(s):  
Bernadette Carroll ◽  
Graeme Hewitt ◽  
Viktor I. Korolchuk
Keyword(s):  
Neurodegenerative Diseases ◽  
Energy Availability ◽  
Future Studies ◽  
Intracellular Degradation ◽  
Age Related ◽  
Autophagy Induction ◽  
Social Importance ◽  
Cellular Dysfunction ◽  
Autophagy Activity ◽  
Intense Research

Autophagy is a process of lysosome-dependent intracellular degradation that participates in the liberation of resources including amino acids and energy to maintain homoeostasis. Autophagy is particularly important in stress conditions such as nutrient starvation and any perturbation in the ability of the cell to activate or regulate autophagy can lead to cellular dysfunction and disease. An area of intense research interest is the role and indeed the fate of autophagy during cellular and organismal ageing. Age-related disorders are associated with increased cellular stress and assault including DNA damage, reduced energy availability, protein aggregation and accumulation of damaged organelles. A reduction in autophagy activity has been observed in a number of ageing models and its up-regulation via pharmacological and genetic methods can alleviate age-related pathologies. In particular, autophagy induction can enhance clearance of toxic intracellular waste associated with neurodegenerative diseases and has been comprehensively demonstrated to improve lifespan in yeast, worms, flies, rodents and primates. The situation, however, has been complicated by the identification that autophagy up-regulation can also occur during ageing. Indeed, in certain situations, reduced autophagosome induction may actually provide benefits to ageing cells. Future studies will undoubtedly improve our understanding of exactly how the multiple signals that are integrated to control appropriate autophagy activity change during ageing, what affect this has on autophagy and to what extent autophagy contributes to age-associated pathologies. Identification of mechanisms that influence a healthy lifespan is of economic, medical and social importance in our ‘ageing’ world.

Sign in / Sign up

Export Citation Format

Share Document