Redox control of G(1)/S cell cycle regulators during nitric oxide-mediated cell cycle arrest

J Cell Physiol. 2007 Sep;212(3):827-39. doi: 10.1002/jcp.21079.

Abstract

Redox regulation of cell cycle progression during nitric oxide (NO) mediated cytostasis is not well-understood. In this study, we investigated the role of the intracellular antioxidant glutathione (GSH) in regulating specific signaling events that are associated with NO-mediated cell cycle arrest. Manipulation of intracellular GSH content through pharmacological inhibition of glutamate-cysteine ligase (GCL) indicated that GSH depletion potentiated nitrosative stress, DNA damage, phosphorylation of the tumor suppressor p53 (Ser-18) and upregulation of p21(cip1/waf1) upon NO stimulation. However, we found that neither overexpression of a dominant negative p53 nor pharmacological inhibition of p53 with cyclic pifithrin-alpha (cPFT-alpha) was sufficient to reverse NO-mediated cell cycle arrest or hypophosphorylation of retinoblastoma protein (Rb). We found that the decrease in cyclin D1 levels induced by NO was GSH-sensitive implying that the redox regulation of NO-mediated cytostasis was a multifaceted process and that both p53/p21(cip1/waf1) and p53 independent cyclin D1 pathways were involved. Together, our results demonstrate that GSH serves as an important component of cellular protective mechanisms against NO-derived nitrosative stress to regulate DNA damage checkpoint.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Benzothiazoles / pharmacology
  • Buthionine Sulfoximine / pharmacology
  • Cell Cycle Proteins / antagonists & inhibitors
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism*
  • Cell Proliferation / drug effects*
  • Cyclin D
  • Cyclin-Dependent Kinase Inhibitor p21 / metabolism
  • Cyclins / metabolism
  • DNA Damage
  • Dose-Response Relationship, Drug
  • Enzyme Inhibitors / pharmacology
  • Fibroblasts / drug effects*
  • Fibroblasts / enzymology
  • Fibroblasts / metabolism
  • G1 Phase / drug effects
  • Glutamate-Cysteine Ligase / antagonists & inhibitors
  • Glutamate-Cysteine Ligase / metabolism
  • Glutathione / metabolism*
  • Mice
  • NIH 3T3 Cells
  • Nitric Oxide / metabolism*
  • Nitric Oxide Donors / pharmacology*
  • Oxidation-Reduction
  • Phosphorylation
  • Retinoblastoma Protein / metabolism
  • S Phase / drug effects
  • Toluene / analogs & derivatives
  • Toluene / pharmacology
  • Transfection
  • Triazenes / pharmacology*
  • Tumor Suppressor Protein p53 / antagonists & inhibitors
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • 1-hydroxy-2-oxo-3,3-bis(2-aminoethyl)-1-triazene
  • Benzothiazoles
  • Cdkn1a protein, mouse
  • Cell Cycle Proteins
  • Cyclin D
  • Cyclin-Dependent Kinase Inhibitor p21
  • Cyclins
  • Enzyme Inhibitors
  • Nitric Oxide Donors
  • Retinoblastoma Protein
  • Triazenes
  • Tumor Suppressor Protein p53
  • Nitric Oxide
  • Toluene
  • Buthionine Sulfoximine
  • pifithrin
  • Glutamate-Cysteine Ligase
  • Glutathione