Evaluation of EGCG Loading Capacity in DMPC Membranes

Abstract

Catechins are molecules with potential use in different pathologies such as diabetes and cancer, but their pharmaceutical applications are often hindered by their instability in the bloodstream. This issue can be circumvented using liposomes as their nanocarriers for in vivo delivery. In this work, we studied the molecular details of (-)-epigallocatechin-3-gallate (EGCG) interacting with 1,2-dimyristoyl-snglycero-3-phosphocholine (DMPC) monolayer/bilayer systems to understand the catechin loading ability and liposome stability, using experimental and computational techniques. The molecular dynamics simulations show the EGCG molecules deep inside the lipid bilayer, positioned below the lipid ester groups, generating a concentration-dependent lipid condensation. This effect was also inferred from the surface pressure isotherms of DMPC monolayers. In the polarizationmodulated infrared reflection absorption spectra assays, the predominant effect at higher concentrations of EGCG (e.g., 20 mol %) was an increase in lipid tail disorder. The steady-state fluorescence data confirmed this disordered state, indicating that the catechin-induced liposome aggregation outweighs the condensation effects. Therefore, by adding more than 10 mol % EGCG to the liposomes, a destabilization of the vesicles occurs with the ensuing release of entrapped catechins. The loading capacity for DMPC seems to be limited by its disordered lipid arrangements, typical of a fluid phase. To further increase the clinical usefulness of liposomes, lipid bilayers with more stable and organized assemblies should be employed to avoid aggregation at large concentrations of catechin.

Polycaprolactone/Gelatin Nanofiber Membranes Containing EGCG-Loaded Liposomes and Their Potential Use for Skin Regeneration

“…The GTA vapor process may also cross-link the DPPC liposomes amino groups, improving their adsorption onto the PCL/gelatin nanofibers as well as the EGCG release profile from the fibers. The DPPC liposomes 45 exhibited characteristic peaks at 2920, 2850, 1730, 1220 and 1080 cm −1 assigned to asymmetric and symmetric CH 2 hydrocarbon stretching, C O stretching, asymmetric and symmetric PO stretching, respectively, having the major bands in the fingerprinting region of PCL. Moreover, typical EGCG peaks 24 were located around 3360 cm −1 (phenyl OH stretching), 1695 cm −1 (CO gallic acid stretching), 1519 cm −1 (CC stretching), and 1016 cm −1 (CH stretching of aromatic rings).…”

Effect of high sodium ion level on the interaction of AmB with a cholesterol-rich phospholipid monolayer

“…However, the composition of the bilayer is difficult to control precisely, and information about the thermodynamic characteristics of the membrane system cannot be obtained. A Langmuir monolayer model can accurately control components of membrane, environment, temperature, and other conditions, and it is very suitable for exploring the lipid–drug interaction ( Pires et al, 2019 ; Pires et al, 2020 ; Jurak et al, 2021 ; Jochelavicius et al, 2022 ). The surface pressure and the molecular packing of the lipid membrane can be modified in the monolayer model ( Pivetta et al, 2023 ).…”

Epigallocatechin-3-gallate: A phytochemical as a promising drug candidate for the treatment of Parkinson’s disease

“…Accumulating evidence has suggested a number of sources and mechanisms for oxidative stress in PD, which include nicotinamide adenine dinucleotide phosphate oxidase (NOX) activation, mitochondrial dysfunction, the catabolism of dopamine by auto-oxidation, iron (Fe 2+ ) accumulation ( Wang et al, 2021 ). Oxidative stress causes injury to macromolecular components (i.e., DNA, proteins, and lipids) ( Pires et al, 2019a ; 2019b ; 2019c ; 2019d , 2020 ), resulting in cellular dysfunction and, eventually, dopaminergic neuron death ( Wang et al, 2021 ). Given the important role of oxidative stress in PD, antioxidant supplements could be a reasonable therapeutic approach to halting PD progression ( Chang and Chen, 2020 ), as it could mitigate oxidative stress-dependent neuronal injury ( Buendia et al, 2016 ).…”