Alterations in cell-adhesive and migratory properties of proximal tubule and collecting duct cells from bcl-2 -/- mice

Am J Physiol Renal Physiol. 2004 Dec;287(6):F1154-63. doi: 10.1152/ajprenal.00129.2004. Epub 2004 Aug 3.

Abstract

Bcl-2 protects cells from apoptosis initiated by a variety of stimuli including loss of cell adhesion. Bcl-2 -/- mice develop renal hypoplastic/cystic dysplasia with renal cyst formation coinciding with renal maturation in normal mice. To gain a better understanding of the role cell-adhesive mechanisms play during renal maturation, we generated proximal tubule and collecting duct cell lines from postnatal day 10 (P10) and P20 bcl-2 +/+ and bcl-2 -/- mice. Very little is known about the role cell-adhesive and migratory mechanisms play during renal maturation. We observed that modulation of cell-adhesive properties, which normally occur in a nephron segment-specific manner during renal maturation, and cell migration were altered in cells from bcl-2 -/- mice. Enhanced migration of bcl-2 -/- proximal tubule cells in a scratch wound assay was completely inhibited by incubation with PP1 (Src inhibitor) and moderately affected by incubation with SB-203580 (p38 inhibitor). These cells expressed increased levels of fibronectin and had numerous central focal adhesions. P20 bcl-2 -/- proximal tubule cells adhered to fibronectin but adhered poorly to collagen, vitronectin, or laminin. Collecting duct cells, similar to proximal tubule cells from bcl-2 -/- mice, demonstrated enhanced migration in a scratch wound assay that was inhibited by incubation with PP1. Migration of these cells was moderately affected by incubation with PD-98059 (MEK inhibitor) or LY-294002 (PI3 kinase inhibitor), whereas incubation with SB-203580 had no effect. P10 bcl-2 -/- collecting duct cells also expressed increased levels of fibronectin but decreased levels of thrombospondin-1 and demonstrated precocious binding to fibronectin and vitronectin compared with bcl-2 +/+ cells. The ability of P20 bcl-2 +/+ collecting duct cells to adhere to fibronectin and vitronectin corresponded with a decline in thrombospondin-1 expression. Therefore, alterations in cell-adhesive and migratory characteristics may be an early indicator of aberrant renal epithelial cell differentiation.

Publication types

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

MeSH terms

  • Animals
  • Cell Adhesion / physiology*
  • Cell Communication
  • Cell Differentiation
  • Cell Movement / physiology*
  • Cells, Cultured
  • Extracellular Matrix / physiology
  • Extracellular Matrix Proteins / metabolism
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Fibronectins / metabolism
  • Integrin alpha5 / analysis
  • Kidney Tubules, Collecting / cytology*
  • Kidney Tubules, Collecting / physiology
  • Kidney Tubules, Proximal / cytology*
  • Kidney Tubules, Proximal / physiology
  • Mice
  • Mice, Knockout
  • Phosphatidylinositol 3-Kinases / metabolism
  • Proto-Oncogene Proteins c-bcl-2 / deficiency*
  • Proto-Oncogene Proteins c-bcl-2 / physiology*
  • Signal Transduction
  • Thrombospondin 1 / metabolism
  • p38 Mitogen-Activated Protein Kinases / metabolism
  • src-Family Kinases / metabolism

Substances

  • Extracellular Matrix Proteins
  • Fibronectins
  • Integrin alpha5
  • Proto-Oncogene Proteins c-bcl-2
  • Thrombospondin 1
  • Phosphatidylinositol 3-Kinases
  • src-Family Kinases
  • Extracellular Signal-Regulated MAP Kinases
  • p38 Mitogen-Activated Protein Kinases