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Autophagy and VMP1 expression are early cellular events in experimental diabetes

Daniel Grasso1, Maria L Sacchetti, Lidia Bruno

  • 1Department of Physiology, School of Medicine, University of Buenos Aires, Buenos Aires, Argentina.

Pancreatology : Official Journal of the International Association of Pancreatology (IAP) ... [Et Al.]
|December 17, 2008
PubMed
Abstract

Insights

Experimental diabetes activates VMP1 protein expression and autophagy in pancreas beta cells. This study reveals VMP1

Area of Science:

  • Cell Biology
  • Endocrinology
  • Molecular Biology

Background:

  • The VMP1 protein is known to trigger autophagy in mammalian cells.
  • Experimental diabetes induced by streptozotocin (STZ) activates VMP1 expression and autophagy in pancreas beta cells.

Purpose of the Study:

  • To investigate the role of VMP1 in the cellular response to experimental diabetes in pancreas beta cells.
  • To confirm VMP1's role in STZ-induced autophagy.

Main Methods:

  • Streptozotocin (STZ) treatment in male Wistar rats and isolated rat pancreas islets.
  • Reverse transcription-polymerase chain reaction (RT-PCR) for VMP1 induction.
  • In situ hybridization for VMP1 mRNA localization.
  • Electron microscopy for autophagy morphology.
  • LC3 and VMP1 expression analysis and co-localization studies.

Main Results:

  • STZ treatment rapidly induced VMP1 expression in pancreas beta cells.
  • Autophagy morphology, confirmed by LC3 expression and LC3-VMP1 co-localization, was observed.
  • Apoptotic cell death and beta cell loss occurred, with VMP1 expression persisting in remaining cells.
  • VMP1-Beclin1 co-localization suggested involvement in autophagic process activation.

Conclusions:

  • Pancreas beta cells activate VMP1 expression and autophagy in response to experimental diabetes.
  • VMP1 plays a role in the early cellular events during experimental diabetes.

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