Alternations of 14-3-3 θ and β protein levels in brain during experimental sepsis

J Neurosci Res. 2011 Sep;89(9):1409-18. doi: 10.1002/jnr.22673. Epub 2011 May 26.

Abstract

The 14-3-3 family members play a crucial role in the determination of cell fate, exerting their antiapoptotic activity through directly interfering with the critical function of the mitochondrial core proapoptotic machinery. Dimerization of 14-3-3 is vital for the interaction with many of its client proteins and is regulated by phosphorylation. In a previous study, we observed time-dependent neuronal apoptosis during sepsis. Therefore, in the present study, we sought to evaluate the expression of 14-3-3 θ and β isoforms in septic brain and their association with apoptosis. Sepsis was induced by a CLP model in Wistar rats that were sacrificed at predefined time points. Flow cytometric analysis showed a sepsis-induced, time-dependent alteration of 14-3-3 θ and β isoforms in both Neun(+) and GFAP(+) cells. 14-3-3 θ was linearly correlated with apoptosis, and stratified analysis for alive and apoptotic neuronal cells demonstrated a gradual down-regulation of θ isoform in alive neurons and astrocytes. The phospho-P38 (pP38) MAP kinase levels were altered in a time-dependent manner during sepsis, presenting a peak at 6 hr post-CLP. A significant correlation between the two isoforms of 14-3-3 was observed in septic rats, with the θ isoform predominant at all time points. The hippocampus, Purkinje cells, and glia-like cells showed intense immunohistochemical reactivity for 14-3-3 θ isoform, whereas the choroid plexus showed constantly increased β isoform expression. Our results showed that sepsis alters the expression of both 14-3-3 θ and β isoforms in a time-, cell-, and topography-dependent manner.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 14-3-3 Proteins / metabolism*
  • Animals
  • Apoptosis / physiology*
  • Brain / metabolism*
  • Brain / pathology
  • Cecum / surgery
  • Disease Models, Animal
  • Male
  • Neurons / metabolism*
  • Neurons / pathology
  • Protein Isoforms
  • Rats
  • Rats, Wistar
  • Sepsis / metabolism*
  • Time Factors
  • Tissue Distribution

Substances

  • 14-3-3 Proteins
  • Protein Isoforms