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Strategies for Tracking Anastasis, A Cell Survival Phenomenon that Reverses Apoptosis
12:55

Strategies for Tracking Anastasis, A Cell Survival Phenomenon that Reverses Apoptosis

Published on: February 16, 2015

Early apoptotic vascular signaling is determined by Sirt1 through nuclear shuttling, forkhead trafficking, bad, and

Jinling Hou1, Zhao Zhong Chong, Yan Chen Shang

  • 1Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201, USA.

Current Neurovascular Research
|April 8, 2010
PubMed

Insights

Endothelial cell SIRT1 prevents apoptosis in diabetes mellitus (DM) by regulating nuclear transport and downstream signaling pathways. SIRT1 activation protects against vascular complications in DM.

Area of Science:

  • Endothelial cell biology
  • Molecular mechanisms of apoptosis
  • Diabetes mellitus complications

Background:

  • Diabetes mellitus (DM) complications significantly impact the endothelium, affecting multiple organ systems.
  • Innovative treatments targeting cell survival pathways are needed for endothelial dysfunction in DM.
  • Endothelial cell (EC) SIRT1 plays a crucial role in cellular longevity and preventing apoptosis.

Purpose of the Study:

  • To investigate the role of endothelial cell SIRT1 in preventing apoptosis during elevated D-glucose exposure.
  • To elucidate the molecular mechanisms by which SIRT1 exerts cytoprotective effects in diabetic conditions.
  • To identify SIRT1-mediated pathways as potential therapeutic targets for diabetic vascular complications.

Main Methods:

  • Utilized a clinically relevant model of DM with elevated D-glucose.
  • Modulated SIRT1 activity and performed gene knockdown studies for SIRT1 and FoxO3a.
  • Assessed phosphatidylserine externalization, DNA degradation, and subcellular localization of SIRT1.
  • Investigated the involvement of Akt1, FoxO3a phosphorylation and trafficking, mitochondrial membrane permeability, and caspase activation.

Main Results:

  • Endothelial cell SIRT1 is vital for preventing early apoptotic membrane changes and DNA degradation in DM.
  • Elevated D-glucose sequesters SIRT1 in the cytoplasm; its activation leads to nuclear translocation and cytoprotection.
  • SIRT1 activation averts apoptosis by upregulating Akt1, inhibiting FoxO3a nuclear translocation and pro-apoptotic signaling.
  • SIRT1 activation modulates mitochondrial integrity, prevents cytochrome c release, Bad activation, and caspase cascade progression.

Conclusions:

  • Vascular SIRT1 is a critical regulator of endothelial cell apoptosis in diabetes mellitus.
  • SIRT1 controls apoptotic signaling through Akt1 activation, FoxO3a modification, and mitochondrial pathways.
  • Targeting vascular SIRT1 offers a promising therapeutic strategy for mitigating diabetic vascular complications.

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