Lack of fibulin-3 alters regenerative tissue responses in the primary olfactory pathway

Matrix Biol. 2009 Sep;28(7):406-15. doi: 10.1016/j.matbio.2009.06.001. Epub 2009 Jun 9.

Abstract

The adult olfactory epithelium has maintained the ability to reconstitute its olfactory sensory neurons (OSNs) from a basal progenitor cell compartment. This allows for life-long turnover and replacement of receptor components as well as repair of the primary olfactory pathway in response to injury and environmental insults. The present study investigated whether fibulin-3, a glycoprotein in the extracellular matrix and binding partner of tissue inhibitor of metalloproteinases-3 (TIMP-3), plays a role in ongoing plasticity and regenerative events in the adult primary olfactory pathway. In wild-type control mice, fibulin-3 protein was detected on IB4(+)CD31(+) blood vessels, nerve fascicles and the basement membrane underneath the olfactory epithelium. After target ablation (olfactory bulbectomy), fibulin-3 was also abundantly present in the central nervous system (CNS) scar tissue that occupied the bulbar cavity. Using two different lesion models, i.e. intranasal Triton X-100 lesion and olfactory bulbectomy, we show that fibulin-3 deficient (Efemp1(-/-)) mice have impaired recovery of the olfactory epithelium after injury. Ten days post-injury, Efemp1(-/-) mice showed altered basal stem/progenitor cell proliferation and increased overall numbers of mature (olfactory marker protein (OMP) -positive) versus immature OSNs. However, compromised regenerative capacity of the primary olfactory pathway in Efemp1(-/-) mice was evidenced by reduced numbers of mature OSNs at the later time point of 42 days post-injury. In addition to these neural differences there were consistent changes in blood vessel structure in the olfactory lamina propria of Efemp1(-/-) mice. Overall, these data suggest a role for fibulin-3 in tissue maintenance and regeneration in the adult olfactory pathway.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Extracellular Matrix Proteins / genetics
  • Extracellular Matrix Proteins / metabolism*
  • Female
  • Humans
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Knockout
  • Nerve Regeneration / physiology*
  • Olfactory Bulb / cytology
  • Olfactory Bulb / pathology
  • Olfactory Bulb / physiology
  • Olfactory Mucosa / cytology
  • Olfactory Mucosa / pathology
  • Olfactory Mucosa / physiology
  • Olfactory Pathways / anatomy & histology
  • Olfactory Pathways / pathology
  • Olfactory Pathways / physiology*
  • Stem Cells / cytology
  • Stem Cells / physiology

Substances

  • Efemp1 protein, mouse
  • Extracellular Matrix Proteins