Related Experiment Video
Updated: Feb 26, 2026
Preparation and Characterization of Lipophilic Doxorubicin Pro-drug Micelles
Published on: August 2, 2016
Influence of doxorubicin on model cell membrane properties: insights from in vitro and in silico studies
Ana Catarina Alves1, Aniket Magarkar2,3, Miguel Horta1
1UCIBIO, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
Abstract:
Despite doxorubicin being commonly used in chemotherapy there still remain significant holes in our knowledge regarding its delivery efficacy and an observed resistance mechanism that is postulated to involve the cell membrane. One possible mechanism is the efflux by protein P-gp, which is found predominantly in cholesterol enriched domains. Thereby, a hypothesis for the vulnerability of doxorubicin to efflux through P-gp is its enhanced affinity for the ordered cholesterol rich regions of the plasma membrane. Thus, we have studied doxorubicin's interaction with model membranes in a cholesterol rich, ordered environment and in liquid-disordered cholesterol poor environment. We have combined three separate experimental protocols: UV-Vis spectrophotometry, fluorescence quenching and steady-state anisotropy and computational molecular dynamics modeling. Our results show that the presence of cholesterol induces a change in membrane structure and doesn't impair doxorubicin's membrane partitioning, but reduces drug's influence on membrane fluidity without directly interacting with it. It is thus possible that the resistance mechanism that lowers the efficacy of doxorubicin, results from an increased density in membrane regions where the efflux proteins are present. This work represents a successful approach, combining experimental and computational studies of membrane based systems to unveil the behavior of drugs and candidate drug molecules.
Insights
Doxorubicin
Area of Science:
- Biochemistry
- Molecular Biology
- Pharmacology
Background:
- Doxorubicin is a widely used chemotherapy drug.
- Its efficacy is limited by drug resistance, potentially involving the cell membrane and P-glycoprotein (P-gp) efflux pumps.
- P-gp is localized in cholesterol-rich membrane domains.
Purpose of the Study:
- To investigate the interaction of doxorubicin with model cell membranes, specifically focusing on cholesterol's role.
- To understand how membrane composition influences doxorubicin's behavior and potential efflux.
- To explore the link between membrane structure and doxorubicin resistance.
Main Methods:
- Combined experimental techniques: UV-Vis spectrophotometry, fluorescence quenching, and steady-state anisotropy.
- Computational modeling using molecular dynamics simulations.
- Studied doxorubicin in both cholesterol-rich (ordered) and cholesterol-poor (disordered) model membranes.
Main Results:
- Cholesterol alters membrane structure but does not hinder doxorubicin partitioning.
- Doxorubicin's influence on membrane fluidity is reduced in the presence of cholesterol.
- No direct interaction between doxorubicin and cholesterol was observed.
Conclusions:
- Doxorubicin resistance may stem from increased drug concentration in membrane regions with efflux proteins like P-gp.
- Cholesterol-rich membranes may facilitate doxorubicin efflux by concentrating the drug near P-gp.
- Integrated experimental and computational approaches are valuable for studying drug-membrane interactions.
