Protein aggregation and ER stress

Navit Ogen-Shtern1, Tamuz Ben David1, Gerardo Z Lederkremer1

  • 1Department of Cell Research and Immunology, George Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel.

Brain Research
|April 3, 2016
PubMed

Insights

Protein aggregation in neurodegenerative diseases triggers endoplasmic reticulum (ER) stress. Intermediate oligomeric protein forms, not final aggregates, are toxic and cause ER stress, suggesting new therapeutic targets.

Area of Science:

  • Neuroscience
  • Molecular Biology
  • Cellular Biology

Background:

  • Protein misfolding and aggregation are hallmarks of neurodegenerative diseases like Alzheimer's and Parkinson's.
  • Endoplasmic reticulum (ER) stress is increasingly recognized as a key factor in the cytotoxicity of these disorders.
  • Current therapies for neurodegenerative diseases are limited, highlighting the need for novel therapeutic strategies.

Purpose of the Study:

  • To review recent findings on the mechanisms linking protein aggregation to ER stress in neurodegenerative diseases.
  • To discuss the significance of ER stress in disease pathogenesis.
  • To explore potential therapeutic approaches targeting ER stress.

Main Methods:

  • Literature review of recent research on protein aggregation and ER stress.
  • Analysis of studies investigating toxic species in neurodegenerative diseases.
  • Examination of therapeutic strategies targeting ER stress pathways.

Main Results:

  • Protein aggregation, involving proteins like amyloid-β, tau, α-synuclein, and huntingtin, follows a common pathway of oligomerization and fibril formation.
  • Intermediate oligomeric forms of aggregated proteins are identified as the primary toxic species and inducers of ER stress.
  • Final amyloid aggregates are less implicated in ER stress and cytotoxicity compared to oligomeric intermediates.

Conclusions:

  • Protein aggregation-induced ER stress is a critical mechanism in neurodegenerative disease pathology.
  • Targeting intermediate oligomeric species and mitigating ER stress presents a promising therapeutic avenue.
  • Further research into these mechanisms could lead to effective treatments for debilitating neurodegenerative conditions.

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