Direct evaluation of intracellular accumulation of free and polymer-bound anthracyclines

T Bogush1, G Smirnova, I Shubina

  • 1Department of Pharmacology and Toxicology, Russian Academy of Medical Sciences, Moscow.

Insights

Nanoparticle drug carriers reduce anthracycline accumulation and DNA binding by 30-40%. Two novel methods accurately quantify drug-DNA interactions for carrier-bound anthracyclines.

Area of Science:

  • Pharmacology
  • Nanotechnology
  • Molecular Biology

Background:

  • Anthracyclines are crucial chemotherapy agents.
  • Nanoparticulate carriers aim to improve drug delivery and efficacy.
  • Understanding drug-DNA interaction is key to optimizing nanocarrier design.

Purpose of the Study:

  • To develop and validate methods for quantifying anthracycline-DNA interactions.
  • To assess the impact of nanoparticulate carriers on intracellular drug accumulation and DNA binding.
  • To compare the behavior of carrier-bound anthracyclines with their free forms.

Main Methods:

  • Quantification of anthracycline-DNA interaction via fluorescence quenching.
  • Measurement of Hoechst 33258 fluorescence displacement assay.
  • Comparison of doxorubicin-nanospheres (dox-NS) and daunorubicin-polyglutamic acid with free drugs.

Main Results:

  • Intracellular accumulation and DNA binding of dox-NS and daunorubicin-polyglutamic acid were reduced by 30-40% compared to free drugs.
  • Pre-incubation with compounds did not alter results for doxorubicin or NS-dox.
  • Both developed methods provided consistent and comparable results.

Conclusions:

  • Nanoparticulate carriers significantly reduce intracellular accumulation and DNA binding of anthracyclines.
  • The fluorescence quenching and displacement assays are reliable for evaluating carrier-bound anthracycline-DNA interactions.
  • These findings aid in the development of improved nanocarrier-based drug delivery systems.