Molecular imaging of cell death in vivo by a novel small molecule probe

Apoptosis. 2006 Dec;11(12):2089-101. doi: 10.1007/s10495-006-0282-7.

Abstract

Apoptosis has a role in many medical disorders, therefore assessment of apoptosis in vivo can be highly useful for diagnosis, follow-up and evaluation of treatment efficacy. ApoSense is a novel technology, comprising low molecular-weight probes, specifically designed for imaging of cell death in vivo. In the current study we present targeting and imaging of cell death both in vitro and in vivo, utilizing NST-732, a member of the ApoSense family, comprising a fluorophore and a fluorine atom, for both fluorescent and future positron emission tomography (PET) studies using an (18)F label, respectively. In vitro, NST-732 manifested selective and rapid accumulation within various cell types undergoing apoptosis. Its uptake was blocked by caspase inhibition, and occurred from the early stages of the apoptotic process, in parallel to binding of Annexin-V, caspase activation and alterations in mitochondrial membrane potential. In vivo, NST-732 manifested selective uptake into cells undergoing cell-death in several clinically-relevant models in rodents: (i) Cell-death induced in lymphoma by irradiation; (ii) Renal ischemia/reperfusion; (iii) Cerebral stroke. Uptake of NST-732 was well-correlated with histopathological assessment of cell-death. NST-732 therefore represents a novel class of small-molecule detectors of apoptosis, with potential useful applications in imaging of the cell death process both in vitro and in vivo.

MeSH terms

  • Animals
  • Brain / cytology
  • Brain / drug effects
  • Brain / pathology
  • Caspase Inhibitors
  • Cell Death / drug effects
  • Cell Membrane / drug effects
  • Cell Membrane / metabolism
  • Enzyme Activation / drug effects
  • Enzyme Inhibitors / pharmacology
  • Flow Cytometry
  • Humans
  • Infarction, Middle Cerebral Artery / chemically induced
  • Infarction, Middle Cerebral Artery / pathology
  • Jurkat Cells
  • Kidney Tubules / drug effects
  • Kidney Tubules / pathology
  • Membrane Potential, Mitochondrial / drug effects
  • Mice
  • Models, Animal
  • Molecular Probe Techniques*
  • Molecular Probes / analysis
  • Molecular Probes / chemistry
  • Molecular Probes / metabolism*
  • Molecular Probes / toxicity
  • Neoplasms / chemically induced
  • Neoplasms / therapy
  • Neurons / cytology
  • Neurons / drug effects
  • Neurons / pathology
  • Rats
  • Rats, Sprague-Dawley
  • Reperfusion Injury / chemically induced
  • Reperfusion Injury / pathology
  • Time Factors
  • Toxicity Tests

Substances

  • Caspase Inhibitors
  • Enzyme Inhibitors
  • Molecular Probes