Huntingtin aggregation impairs autophagy leading to Argonaute-2 accumulation and global microRNA dysregulation
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ABSTRACT:
ORGANISM(S): Mus musculus Homo sapiens
PROVIDER: GSE78928 | GEO | 2018/08/07
REPOSITORIES: GEO
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2021-12-20 | PXD029689 | Pride
Project description:In this study the generic impact of protein aggregation (aggregation of proteins not associated with neurodegenerative disease) on gene expression in cultured cells was investigated by DNA microarray technology. The survey of gene expression showed that the Hsp40, Hsp70 and Hsp105 genes, all of which have documented aggregation suppression activity, were up-regulated. Unexpectedly, the survey also showed increased expression of the MEK5 gene with concomitant silencing of the MEK3 gene. The expression pattern of MEK5 at the mRNA and protein levels aligns with the kinetics of aggregate formation and dissolution. Cell viability was unaffected by protein aggregates. These findings are of particular importance for chronic neurodegenerative diseases where the intraneuronal accumulation of aggregate-prone proteins are a major characteristic of the diseases. The identification of changes in MEK5 gene expression have been observed in Alzheimer-related diseases which provides new diagnostic and therapeutic avenues in these diseases. The molecular neuropathological findings would not have occurred without the generic microarray analyses.
2005-07-20 | E-MEXP-389 | biostudies-arrayexpress
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Project description:INTRODUCTION: The pathogenicity at differing points along the aggregation pathway of many fibril-forming proteins associated with neurodegenerative diseases is unclear. Understanding the effect of different aggregation states of these proteins on cellular processes is essential to enhance understanding of diseases and provide future options for diagnosis and therapeutic intervention.</br>OBJECTIVES:To establish a robust method to probe the metabolic changes of neuronal cells and use it to monitor cellular response to challenge with three amyloidogenic proteins associated with neurodegenerative diseases in different aggregation states.</br>METHOD: Neuroblastoma SH-SY5Y cells were employed to design a robust routine system to perform a statistically rigorous NMR metabolomics study into cellular effects of sub-toxic levels of alpha-synuclein, amyloid-beta 40 and amyloid-beta 42 in monomeric, oligomeric and fibrillar conformations.</br>RESULTS: This investigation developed a rigorous model to monitor intracellular metabolic profiles of neuronal cells through combination of existing methods. This model revealed eight key metabolites that are altered when neuroblastoma cells are challenged with proteins in different aggregation states. Metabolic pathways associated with lipid metabolism, neurotransmission and adaptation to oxidative stress and inflammation are the predominant contributors to the cellular variance and intracellular metabolite levels. The observed metabolite changes for monomer and oligomer challenge may represent cellular effort to counteract the pathogenicity of the challenge, whereas fibrillar challenge is indicative of system shutdown. This implies that although markers of stress are more prevalent under oligomeric challenge the fibrillar response suggests a more toxic environment.</br>CONCLUSION: This approach is applicable to any cell type that can be cultured in a laboratory (primary or cell line) as a method of investigating how protein challenge affects signalling pathways, providing additional understanding as to the role of protein aggregation in neurodegenerative disease initiation and progression.
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