scholarly journals Ellagic Acid Prevents α-Synuclein Aggregation and Protects SH-SY5Y Cells from Aggregated α-Synuclein-Induced Toxicity via Suppression of Apoptosis and Activation of Autophagy

2021 ◽  
Vol 22 (24) ◽  
pp. 13398
Author(s):  
Mustafa T Ardah ◽  
Nabil Eid ◽  
Tohru Kitada ◽  
M. Emdadul Haque
Keyword(s):  
Ellagic Acid ◽  
Molecular Mechanisms ◽  
Lewy Bodies ◽  
Dopamine Neurons ◽  
Misfolded Proteins ◽  
Concomitant Increase ◽  
Apoptotic Protein ◽  
Enhanced Expression ◽  
Seeding Polymerization

Parkinson’s disease (PD) is a neurodegenerative disease characterized by the loss of dopamine neurons and the deposition of misfolded proteins known as Lewy bodies (LBs), which contain α-synuclein (α-syn). The causes and molecular mechanisms of PD are not clearly understood to date. However, misfolded proteins, oxidative stress, and impaired autophagy are believed to play important roles in the pathogenesis of PD. Importantly, α-syn is considered a key player in the development of PD. The present study aimed to assess the role of Ellagic acid (EA), a polyphenol found in many fruits, on α-syn aggregation and toxicity. Using thioflavin and seeding polymerization assays, in addition to electron microscopy, we found that EA could dramatically reduce α-syn aggregation. Moreover, EA significantly mitigated the aggregated α-syn-induced toxicity in SH-SY5Y cells and thus enhanced their viability. Mechanistically, these cytoprotective effects of EA are mediated by the suppression of apoptotic proteins BAX and p53 and a concomitant increase in the anti-apoptotic protein, BCL-2. Interestingly, EA was able to activate autophagy in SH-SY5Y cells, as evidenced by normalized/enhanced expression of LC3-II, p62, and pAKT. Together, our findings suggest that EA may attenuate α-syn toxicity by preventing aggregation and improving viability by restoring autophagy and suppressing apoptosis.

scholarly journals Pathological Functions of LRRK2 in Parkinson’s Disease

Cells ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 2565
Author(s):  
Ga Ram Jeong ◽  
Byoung Dae Lee
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Molecular Mechanisms ◽  
Lewy Bodies ◽  
Gene Encoding ◽  
Pathogenic Mutations ◽  
Abnormal Increase ◽  
Sporadic Parkinson’S Disease ◽  
Lrrk2 Kinase

Mutations in the gene encoding leucine-rich repeat kinase 2 (LRRK2) are common genetic risk factors for both familial and sporadic Parkinson’s disease (PD). Pathogenic mutations in LRRK2 have been shown to induce changes in its activity, and abnormal increase in LRRK2 kinase activity is thought to contribute to PD pathology. The precise molecular mechanisms underlying LRRK2-associated PD pathology are far from clear, however the identification of LRRK2 substrates and the elucidation of cellular pathways involved suggest a role of LRRK2 in microtubule dynamics, vesicular trafficking, and synaptic transmission. Moreover, LRRK2 is associated with pathologies of α-synuclein, a major component of Lewy bodies (LBs). Evidence from various cellular and animal models supports a role of LRRK2 in the regulation of aggregation and propagation of α-synuclein. Here, we summarize our current understanding of how pathogenic mutations dysregulate LRRK2 and discuss the possible mechanisms leading to neurodegeneration.

MicroRNA-1225-5p acts as a tumor-suppressor in laryngeal cancer via targeting CDC14B

2019 ◽  
Vol 400 (2) ◽  
pp. 237-246 ◽  
Author(s):  
Peng Sun ◽  
Dan Zhang ◽  
Haiping Huang ◽  
Yafeng Yu ◽  
Zhendong Yang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Death ◽  
Cell Division ◽  
Cell Cycle Arrest ◽  
Molecular Mechanisms ◽  
Normal Tissues ◽  
Cycle Arrest ◽  
Enhanced Expression ◽  
Insight Into

Abstract This study aimed to investigate the role of miRNA-1225-5p (miR-1225) in laryngeal carcinoma (LC). We found that the expression of miR-1225 was suppressed in human LC samples, while CDC14B (cell division cycle 14B) expression was reinforced in comparison with surrounding normal tissues. We also demonstrated that enhanced expression of miR-1225 impaired the proliferation and survival of LC cells, and resulted in G1/S cell cycle arrest. In contrast, reduced expression of miR-1225 promoted cell survival. Moreover, miR-1225 resulted in G1/S cell cycle arrest and enhanced cell death. Further, miR-1225 targets CDC14B 3′-UTR and recovery of CDC14B expression counteracted the suppressive influence of miR-1225 on LC cells. Thus, these findings offer insight into the biological and molecular mechanisms behind the development of LC.

scholarly journals Chaperone-mediated hierarchical control in targeting misfolded proteins to aggresomes

2011 ◽  
Vol 22 (18) ◽  
pp. 3277-3288 ◽  
Author(s):  
Xingqian Zhang ◽  
Shu-Bing Qian
Keyword(s):  
Protein Folding ◽  
Protein Misfolding ◽  
Mammalian Cells ◽  
Molecular Mechanisms ◽  
Hierarchical Control ◽  
Dominant Negative ◽  
Misfolded Proteins ◽  
Interacting Protein ◽  
Aggresome Formation

Protein misfolding is a common event in living cells. Molecular chaperones not only assist protein folding; they also facilitate the degradation of misfolded polypeptides. When the intracellular degradative capacity is exceeded, juxtanuclear aggresomes are formed to sequester misfolded proteins. Despite the well-established role of chaperones in both protein folding and degradation, how chaperones regulate the aggregation process remains controversial. Here we investigate the molecular mechanisms underlying aggresome formation in mammalian cells. Analysis of the chaperone requirements for the fate of misfolded proteins reveals an unexpected role of heat shock protein 70 (Hsp70) in promoting aggresome formation. This proaggregation function of Hsp70 relies on the interaction with the cochaperone ubiquitin ligase carboxyl terminal of Hsp70/Hsp90 interacting protein (CHIP). Disrupting Hsp70–CHIP interaction prevents the aggresome formation, whereas a dominant-negative CHIP mutant sensitizes the aggregation of misfolded protein. This accelerated aggresome formation also relies on the stress-induced cochaperone Bcl2-associated athanogene 3. Our results indicate that a hierarchy of cochaperone interaction controls different aspects of the intracellular protein triage decision, extending the function of Hsp70 from folding and degradation to aggregation.

scholarly journals ATF3 Promotes Arsenic-Induced Apoptosis and Oppositely Regulates DR5 and Bcl-xL Expression in Human Bronchial Epithelial Cells

2021 ◽  
Vol 22 (8) ◽  
pp. 4223
Author(s):  
Qiwen Shi ◽  
Bei Hu ◽  
Chen Yang ◽  
Lan Zhao ◽  
Jing Wu ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Arsenic Exposure ◽  
Environmental Pollutants ◽  
Death Receptor ◽  
Airway Epithelial ◽  
Health Issues ◽  
Apoptotic Protein ◽  
Activating Transcription Factor ◽  
Induced Apoptosis

Arsenic is one of the most common environmental pollutants eliciting serious public health issues; however, it is also a well-recognized chemotherapeutic agent for acute promyelocytic leukemia. The association between arsenic exposure and lung diseases has been established, but underlying molecular mechanisms are poorly defined. Here we investigated the toxicology of arsenic in airway epithelium. Arsenic rapidly induced the activating transcription factor ATF3 expression through the JNK and p38 pathways. The ATF3-deficient BEAS-2B cells were relatively resistant to apoptosis upon arsenic exposure, indicating a facilitatory role of ATF3 in arsenic-induced apoptosis. We further showed that ATF3 oppositely regulated the transcription of death receptor (DR5) and Bcl2-like 1 (Bcl-xL) by directly binding to the promoter DR5 and Bcl-xL. Altogether, our findings establish ATF3 as a pro-apoptotic protein in arsenic-induced airway epithelial apoptosis through transcriptionally regulating DR5 and Bcl-xL, highlighting the potential of ATF3 as an early and sensitive biomarker for arsenic-caused lung injury.

scholarly journals Amyloid-like oligomerization of AIMP2 contributes to α-synuclein interaction and Lewy-like inclusion

2020 ◽  
Vol 12 (569) ◽  
pp. eaax0091
Author(s):  
Sangwoo Ham ◽  
Seung Pil Yun ◽  
Hyojung Kim ◽  
Donghoon Kim ◽  
Bo Am Seo ◽  
...  
Keyword(s):  
Lewy Bodies ◽  
Insoluble Fraction ◽  
Dopamine Neurons ◽  
Multifunctional Protein ◽  
Associated Proteins ◽  
Direct Binding ◽  
6 Hydroxydopamine ◽  
Aminoacyl Transfer

Lewy bodies are pathological protein inclusions present in the brain of patients with Parkinson’s disease (PD). These inclusions consist mainly of α-synuclein with associated proteins, such as parkin and its substrate aminoacyl transfer RNA synthetase complex–interacting multifunctional protein-2 (AIMP2). Although AIMP2 has been suggested to be toxic to dopamine neurons, its roles in α-synuclein aggregation and PD pathogenesis are largely unknown. Here, we found that AIMP2 exhibits a self-aggregating property. The AIMP2 aggregate serves as a seed to increase α-synuclein aggregation via specific and direct binding to the α-synuclein monomer. The coexpression of AIMP2 and α-synuclein in cell cultures and in vivo resulted in the rapid formation of α-synuclein aggregates with a corresponding increase in toxicity. Moreover, accumulated AIMP2 in mouse brain was largely redistributed to insoluble fractions, correlating with the α-synuclein pathology. Last, we found that α-synuclein preformed fibril (PFF) seeding, adult Parkin deletion, or oxidative stress triggered a redistribution of both AIMP2 and α-synuclein into insoluble fraction in cells and in vivo. Supporting the pathogenic role of AIMP2, AIMP2 knockdown ameliorated the α-synuclein aggregation and dopaminergic cell death in response to PFF or 6-hydroxydopamine treatment. Together, our results suggest that AIMP2 plays a pathological role in the aggregation of α-synuclein in mice. Because AIMP2 insolubility and coaggregation with α-synuclein have been seen in the PD Lewy body, targeting pathologic AIMP2 aggregation might be useful as a therapeutic strategy for neurodegenerative α-synucleinopathies.

scholarly journals Cofilin 1 promotes the pathogenicity and transmission of pathological α-synuclein in mouse models of Parkinson’s disease

2022 ◽  
Vol 8 (1) ◽  
Author(s):  
Mingmin Yan ◽  
Min Xiong ◽  
Lijun Dai ◽  
Xingyu Zhang ◽  
Yunhong Zha ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Mouse Models ◽  
Molecular Mechanisms ◽  
Lewy Bodies ◽  
Actin Binding ◽  
Actin Binding Protein ◽  
Behavioral Impairments

AbstractThe pathological hallmark of Parkinson’s disease (PD) is the presence of Lewy bodies (LBs) with aggregated α-synuclein being the major component. The abnormal α-synuclein aggregates transfer between cells, recruit endogenous α-synuclein into toxic LBs, and finally trigger neuronal injury. However, the molecular mechanisms mediating the aggregation and transmission of pathological α-synuclein remain unknown. Previously we found that cofilin 1, a member of the actin-binding protein, promotes the aggregation and pathogenicity of α-synuclein in vitro. Here we further investigated the effect of cofilin 1 in mouse models of PD. We found that the mixed fibrils composed of cofilin 1 and α-synuclein are more pathogenic to mice and more prone to propagation than pure α-synuclein fibrils. Overexpression of cofilin 1 enhances the seeding and spreading of α-synuclein aggregates, and induces PD-like behavioral impairments in mice. Together, these results illustrate the important role of cofilin 1 in the pathogenicity and transmission of α-synuclein during the onset and progression of PD.

How do histone modifications contribute to transgenerational epigenetic inheritance in C. elegans?

2020 ◽  
Vol 48 (3) ◽  
pp. 1019-1034 ◽  
Author(s):  
Rachel M. Woodhouse ◽  
Alyson Ashe
Keyword(s):  
Histone Modifications ◽  
Molecular Mechanisms ◽  
Epigenetic Inheritance ◽  
Nematode Caenorhabditis Elegans ◽  
Histone Methyltransferases ◽  
Transgenerational Epigenetic Inheritance ◽  
C Elegans ◽  
Recent Developments ◽  
Gene Regulatory

Gene regulatory information can be inherited between generations in a phenomenon termed transgenerational epigenetic inheritance (TEI). While examples of TEI in many animals accumulate, the nematode Caenorhabditis elegans has proven particularly useful in investigating the underlying molecular mechanisms of this phenomenon. In C. elegans and other animals, the modification of histone proteins has emerged as a potential carrier and effector of transgenerational epigenetic information. In this review, we explore the contribution of histone modifications to TEI in C. elegans. We describe the role of repressive histone marks, histone methyltransferases, and associated chromatin factors in heritable gene silencing, and discuss recent developments and unanswered questions in how these factors integrate with other known TEI mechanisms. We also review the transgenerational effects of the manipulation of histone modifications on germline health and longevity.

Mesophyll conductance: the leaf corridors for photosynthesis

2020 ◽  
Vol 48 (2) ◽  
pp. 429-439 ◽  
Author(s):  
Jorge Gago ◽  
Danilo M. Daloso ◽  
Marc Carriquí ◽  
Miquel Nadal ◽  
Melanie Morales ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Main Role ◽  
Mesophyll Conductance ◽  
Future Studies ◽  
Cell Structures ◽  
Leaf Tissues ◽  
Change Framework ◽  
Chloroplast Stroma

Besides stomata, the photosynthetic CO2 pathway also involves the transport of CO2 from the sub-stomatal air spaces inside to the carboxylation sites in the chloroplast stroma, where Rubisco is located. This pathway is far to be a simple and direct way, formed by series of consecutive barriers that the CO2 should cross to be finally assimilated in photosynthesis, known as the mesophyll conductance (gm). Therefore, the gm reflects the pathway through different air, water and biophysical barriers within the leaf tissues and cell structures. Currently, it is known that gm can impose the same level of limitation (or even higher depending of the conditions) to photosynthesis than the wider known stomata or biochemistry. In this mini-review, we are focused on each of the gm determinants to summarize the current knowledge on the mechanisms driving gm from anatomical to metabolic and biochemical perspectives. Special attention deserve the latest studies demonstrating the importance of the molecular mechanisms driving anatomical traits as cell wall and the chloroplast surface exposed to the mesophyll airspaces (Sc/S) that significantly constrain gm. However, even considering these recent discoveries, still is poorly understood the mechanisms about signaling pathways linking the environment a/biotic stressors with gm responses. Thus, considering the main role of gm as a major driver of the CO2 availability at the carboxylation sites, future studies into these aspects will help us to understand photosynthesis responses in a global change framework.

The role of the anti-apoptotic protein Bcl-xL for the maintenance of human hematopoiesis

2016 ◽  
Vol 228 (03) ◽  
Author(s):  
S Afreen ◽  
S Bohler ◽  
M Kunze ◽  
JM Weiss ◽  
M Erlacher
Keyword(s):  
Apoptotic Protein

Dementia with Lewy bodies

2018 ◽  
pp. 11-21
Author(s):  
O. S. Levin ◽  
E. E. Vasenina ◽  
A. Sh. Chimagomedova ◽  
N. G. Dudchenko
Keyword(s):  
Parkinson’S Disease ◽  
Dementia With Lewy Bodies ◽  
Cholinesterase Inhibitors ◽  
Lewy Bodies ◽  
Diagnosis And Treatment ◽  
Modern Concept ◽  
Historical Aspect ◽  
Neurodegenerative Process ◽  
Icd 10

Te lecture presents modern concept of the symptoms, diagnosis and treatment of dementia with Lewy bodies (DLB), which accounts for about 10% of cases of dementia. Te nosological status of DLB and the problem of ratio of DLB and Parkinson’s disease which, apparently, represent two phenotypic variants of one neurodegenerative process («diseases with Lewy bodies») are considered in historical aspect. Approaches to the diagnosis and coding of DLB in accordance with ICD-10 are proposed. Te role of cholinesterase inhibitors, antipsychotics, levodopa, rasagiline and other drugs in the treatment of patients with DLB is аnalyzed.

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