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Molecular Docking Characterizes Substrate-Binding Sites and Efflux Modulation Mechanisms within P-Glycoprotein

P-Glycoprotein (Pgp) is one of the best characterized ABC transporters, often involved in the multidrug-resistance phenotype overexpressed by several cancer cell lines. Experimental studies contributed to important knowledge concerning substrate polyspecificity, efflux mechanism, and drug-binding sites. This information is, however, Read more ›

Assessing the Stabilization of P-Glycoprotein’s Nucleotide- Binding Domains by the Linker, Using Molecular Dynamics

This paper focuses on the importance of the intermediate linker sequence for the stabilization of the cytoplasmic portion of murine P-glycoprotein, an ABC transporter involved in Multidrug Resistance (MDR) in cancer. Three putative protein-protein interaction areas were predicted to exist, Read more ›

Enhancing Macrocyclic Diterpenes as Multidrug-Resistance Reversers: Structure–Activity Studies on Jolkinol D Derivatives

The phytochemical study of Euphorbia piscatoria yielded jolkinol D (1) in a large amount, whose derivatization gave rise to 12 ester derivatives (2–13) and hydrolysis to compound 14. The in vitro modulation of P-gp of compounds 1–14 was evaluated through Read more ›

Insights on P-Glycoprotein’s Efflux Mechanism Obtained by Molecular Dynamics Simulations

P-Glycoprotein (P-gp) is often involved in multidrug resistance (MDR) to the pharmacological action of a wide number of anticancer agents. In this article, a series of molecular dynamics simulations of murine’s P-gp were developed, elucidating the importance of the lipid Read more ›

Colon Adenocarcinoma Multidrug Resistance Reverted by Euphorbia Diterpenes: Structure-Activity Relationships and Pharmacophore Modeling

Multidrug resistance (MDR) is a limiting step on the success of cancer chemotherapy. The drug efflux mediated by P-gp (P- glycoprotein) is one of the best studied mechanisms of MDR. This paper focuses on the inhibitory P-gp efflux activity, pharmacophore Read more ›

Toward a Better Pharmacophore Description of P-Glycoprotein Modulators, Based on Macrocyclic Diterpenes from Euphorbia Species

Multidrug resistance related to the increased expression of P-glycoprotein (P-gp) by cancer cells is the major contributor for the failure of chemotherapeutic treatments. Starting from pharmacophores and data already published and in macrocyclic diterpenes isolated from Euphorbia species, a comprehensive Read more ›

Properties and behaviour of tetracyclic allopsoralen derivatives inside a DPPC lipid bilayer model

Allopsoralens are angular psoralen derivatives presenting advantages over the parent compound because of monofunctional DNA-photobinding and consequent lower toxicity. Allopsoralen molecules with three different substituents and different protonation states were studied using the molecular dynamics technique. The location of these Read more ›

Properties and Permeability of Hypericin and Brominated Hypericin in Lipid Membranes

The promising photosensitizing properties of hypericin, a substituted phenanthroperylene quinone naturally found in Saint John’s wort, has led to the proposal that it can be utilized in photodynamic therapy. Structurally modified derivatives are at the present time being investigated to Read more ›

Erratum to ‘Modelling the behavior of 5-aminolevulinic acid and its alkyl esters in a lipid bilayer’ [Chem. Phys. Lett. 463 (2008) 178]

Due to an error in an analysis program, Fig. 4A in our Letter [1] was incorrectly plotted. The corrected graph is given herein. Edvin Erdtman ab, Daniel J.V.A. dos Santos c, Lennart Löfgren d, Leif A. Eriksson a* a Department Read more ›

Modelling the behavior of 5-aminolevulinic acid and its alkyl esters in a lipid bilayer

5-Aminolevulinic acid (5ALA) and ester derivates thereof are used as prodrugs in photodynamic therapy (PDT). The behavior of 5ALA and three esters of 5ALA in a DPPC lipid bilayer is investigated. In particular, the methyl ester displays a very different Read more ›

Theoretical Study of Sequence Selectivity and Preferred Binding Mode of Psoralen with DNA

Psoralen interaction with two models of DNA was investigated using molecular mechanics and molecular dynamics methods. Calculated energies of minor groove binding and intercalation were compared in order to define a preferred binding mode for the ligand.We found that both Read more ›