Uptake and DNA photodamage induced in plant cells in vivo by two cationic porphyrins

Mutagenesis. 1989 Mar;4(2):157-9. doi: 10.1093/mutage/4.2.157.

Abstract

The in vivo uptake of two cationic porphyrins: mesotetra (4-N-methylpyridyl) porphine (T4MPyP) and its zinc complex (ZnT4MPyP) was determined in Allium cepa meristematic cells. Both photosensitizers (10(-7) M for 4 h) penetrated into the nucleus producing a red fluorescence of chromatin under blue-violet (436 nm) exciting light. The ability of T4MPyP and ZnT4MPyP to induce DNA photodamage was measured by the sister chromatid exchange (SCE) test. 5-Bromo-2'-deoxyuridine-substituted chromosomes treated with both the porphyrins (10(-8)M for 4 h) showed increased frequencies of SCE when they were postirradiated with 436 nm light. A higher genotoxic effect was observed for ZnT4MPyP than the other compound.

MeSH terms

  • Allium / drug effects
  • Allium / genetics*
  • Cations / pharmacokinetics
  • DNA Damage*
  • Light*
  • Mesoporphyrins / pharmacokinetics
  • Mesoporphyrins / toxicity*
  • Metalloporphyrins / pharmacokinetics
  • Metalloporphyrins / toxicity*
  • Mutagenicity Tests
  • Mutagens*
  • Porphyrins / pharmacokinetics*
  • Porphyrins / toxicity*
  • Sister Chromatid Exchange / drug effects

Substances

  • Cations
  • Mesoporphyrins
  • Metalloporphyrins
  • Mutagens
  • Porphyrins
  • tetra(4-N-methylpyridyl)porphine
  • zinc tetra(4-N-methylpyridyl)porphine