Involvement of early growth response-2 (Egr-2) in lipopolysaccharide-induced neuroinflammation

J Mol Histol. 2013 Jun;44(3):249-57. doi: 10.1007/s10735-013-9482-y. Epub 2013 Jan 11.

Abstract

Early growth response-2 (Egr-2) protein is a transcription factor, which belongs to Egr family which involve in modulating the peripheral immune response, by means of the induction of differentiation of lymphocyte precursors, activation of T and B cells. Egr-2 plays essential roles in peripheral nerve myelination, adipogenesis, tissue repair and fibrosis, immune tolerance; however, its regulation and role in central nervous system (CNS) remain poorly understood. In contrast to Egr-1, which has been extensively investigated, the regulation and function of Egr-2 remains less well characterized. To elaborate whether Egr-2 was involved in CNS injury, we performed a neuroinflammatory model by lipopolysaccharide (LPS) lateral ventral injection in adult rats. Egr-2 expression was strongly induced in active glia cells (astrocytes and microglias) in inflamed brain cortex. In vitro studies indicated that the upregulation of Egr-2 may be involved in the subsequent glia cellular activation following LPS exposure; and knock down of Egr-2 in primary mixed glial cultures (MGC) by siRNA showed that Egr-2 promoted the synthesis of TNF-α. Collectively, these results suggested Egr-2 may be important in host defense in CNS immune response, which might provide a potential target to the treatment of neuroinflammation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes / metabolism
  • Cell Proliferation
  • Cells, Cultured
  • Central Nervous System Diseases / genetics*
  • Central Nervous System Diseases / metabolism*
  • Cerebral Cortex / metabolism
  • Early Growth Response Protein 2 / genetics*
  • Early Growth Response Protein 2 / metabolism*
  • Inflammation / chemically induced
  • Inflammation / genetics*
  • Inflammation / metabolism*
  • Inflammation Mediators / metabolism
  • Lipopolysaccharides / pharmacology
  • Male
  • Microglia / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Tumor Necrosis Factor-alpha / metabolism
  • Up-Regulation

Substances

  • Early Growth Response Protein 2
  • Inflammation Mediators
  • Lipopolysaccharides
  • Tumor Necrosis Factor-alpha