Metallothionein-I overexpression decreases brain pathology in transgenic mice with astrocyte-targeted expression of interleukin-6

J Neuropathol Exp Neurol. 2003 Mar;62(3):315-28. doi: 10.1093/jnen/62.3.315.

Abstract

Transgenic expression of interleukin-6 (IL-6) in the CNS under the control of the glial fibrillary acidic protein (GFAP) gene promoter (GFAP-IL6 mice) causes significant damage and alters the expression of many genes, including a dramatic upregulation of metallothionein-I (MT-I). The findings in this report support the idea that the upregulation of MT-I observed in GFAP-IL6 mice is an important mechanism for coping with brain damage. Thus, GFAP-IL6 mice that were crossed with TgMTI transgenic mice (GFAP-IL6xTgMTI) and overexpressed MT-I in the brain showed a decreased upregulation of cytokines such as IL-6 and a diminished recruitment and activation of macrophages and T cells throughout the CNS but mainly in the cerebellum. The GFAP-IL6 mice showed clear evidence of increased oxidative stress, which was significantly decreased by MT-I overexpression. Interestingly, MT-I overexpression increased angiogenesis in GFAP-IL6 mice but not in control littermates. Overall, the results strongly suggest that MT-I+II proteins are valuable factors that protect against cytokine-induced CNS injury.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Astrocytes / metabolism*
  • Brain / metabolism*
  • Brain / pathology*
  • Female
  • Gene Expression Regulation / physiology*
  • Glial Fibrillary Acidic Protein / biosynthesis
  • Glial Fibrillary Acidic Protein / genetics
  • Interleukin-6 / biosynthesis*
  • Interleukin-6 / genetics
  • Male
  • Metallothionein / biosynthesis*
  • Metallothionein / genetics
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Up-Regulation / genetics

Substances

  • Glial Fibrillary Acidic Protein
  • Interleukin-6
  • Metallothionein