Respective roles of inflammation and axonal breakdown in the regulation of peripheral nerve hemopexin: an analysis in rats and in C57BL/Wlds mice

J Neuroimmunol. 2000 Jul 10;107(1):29-41. doi: 10.1016/s0165-5728(00)00246-0.


We have previously demonstrated that one of the peripheral nerve responses to injury is the overexpression of hemopexin (HPX). Here, we demonstrate that Wallerian degeneration is required for this response, since HPX does not increase in C57BL/Wlds mice, which display a severely impaired Wallerian degeneration. We also show that HPX synthesis is dramatically increased in macrophages during their activation or after IL-6 stimulation. However, IL-6-driven HPX overexpression occurs in vivo and in vitro in the absence of substantial macrophage invasion. We conclude that, after nerve injury, HPX overexpression occurs first in Schwann cells as a result of axotomy and is subsequently regulated by inflammation. Furthermore, our results and those already described suggest that IL-6, synthesized by the various cell types producing HPX, control nerve HPX expression via paracrine and autocrine mechanisms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Axons / physiology*
  • Axons / ultrastructure
  • Cells, Cultured
  • Hemopexin / metabolism*
  • Lipopolysaccharides / pharmacology
  • Lysophosphatidylcholines / pharmacology
  • Macrophages / metabolism
  • Mice
  • Mice, Inbred C57BL / genetics
  • Mice, Mutant Strains
  • Neuritis / metabolism
  • Neuritis / pathology
  • Neuritis / physiopathology*
  • Optic Nerve Injuries / metabolism
  • Peripheral Nerves / metabolism*
  • Peripheral Nervous System Diseases / metabolism
  • Peripheral Nervous System Diseases / pathology
  • Peripheral Nervous System Diseases / physiopathology*
  • Rats
  • Rats, Sprague-Dawley
  • Sciatic Nerve / injuries
  • Sciatic Nerve / metabolism
  • Tissue Distribution
  • Wallerian Degeneration / pathology
  • Wallerian Degeneration / physiopathology


  • Lipopolysaccharides
  • Lysophosphatidylcholines
  • Hemopexin