Corticoids modulate liposome membrane fluidity and permeability depending on membrane composition and experimental
Samar Kaddah1, Nathalie Khreich2, Fouad Kaddah3
1Bioactive Molecules Research Laboratory, Faculty of Sciences, Lebanese University, Lebanon; Laboratoire d'Automatique et de Génie des Procédés (LAGEP), Université Claude Bernard, Lyon 1, France.
Biochimie
|June 24, 2018
Summary
This study reveals that glucocorticoid concentration, cholesterol content, and experimental design critically influence how these drugs affect liposome membrane fluidity and permeability. Understanding these factors is key for accurate drug effect analysis.
Area of Science:
- Pharmacology
- Materials Science
- Biophysics
Background:
- Literature data on drug effects on lipid membranes is inconsistent.
- Glucocorticoids (GRs) are widely used drugs with potential membrane interactions.
- Liposome composition and experimental design may influence observed drug effects.
Purpose of the Study:
- To investigate the impact of liposome composition and experimental protocol on glucocorticoid- (GRs) modulating membrane fluidity and permeability.
- To clarify inconsistencies in literature regarding GRs' effects on lipid membranes.
- To identify critical parameters influencing GR-membrane interactions.
Main Methods:
- Prepared GR-loaded liposomes using dipalmitoylphosphatidylcholine (DPPC) and cholesterol (CHOL) via REV technique.
- Characterized liposomes for size, homogeneity, encapsulation efficiency, and loading rates.
- Assessed membrane fluidity using spin probes (DSA) and permeability via sulforhodamine B (SRB) leakage assays.
- Analyzed SRB release kinetics using the Higuchi model.
Main Results:
- All liposome formulations showed monodispersed size (~0.4 μm) with high DPPC and CHOL incorporation (>95%).
- High GR loading rates were achieved (>81%), except for fludrocortisone acetate and prednisolone.
- Glucocorticoid concentration, cholesterol content, and incubation time significantly impacted membrane fluidity and permeability.
Conclusions:
- Liposome composition, specifically cholesterol content, and experimental parameters like incubation time are critical for analyzing GR effects on membrane properties.
- The study highlights the importance of standardized protocols for reproducible results in drug-membrane interaction studies.
- Findings provide a foundation for understanding and predicting glucocorticoid behavior within lipid bilayers.
More Related Videos
Related Concept Videos
01:23Membrane Fluidity
174.7K
Cell membranes are composed of phospholipids, proteins, and carbohydrates loosely attached to one another through chemical interactions. Molecules are generally able to move about in the plane of the membrane, giving the membrane its flexible nature called fluidity. Two other features of the membrane contribute to membrane fluidity: the chemical structure of the phospholipids and the presence of cholesterol in the membrane.
174.7K
01:26Membrane Fluidity
15.9K
Membrane fluidity is explained by the fluid mosaic model of the cell membrane, which describes the plasma membrane structure as a mosaic of components—including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character.
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is...
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is...
15.9K
01:21The Resting Membrane Potential
143.0K
Overview
143.0K
01:16Experimental Designs
18.1K
An experimental design is a systematic process that allows researchers to evaluate the relationship between dependent and independent variables. There are three widely used types of experimental design - pre-experimental design, true experimental design, and quasi-experimental design. In pre-experimental design, the researcher compares the data before and after some interventions or treatments. The true-experimental design has more than one purposefully created group, a commonly measured...
18.1K
01:16Introduction to Membrane Proteins
81.4K
The cell membrane, or plasma membrane, is an ever-changing landscape. It is described as a fluid mosaic where various macromolecules are embedded in the phospholipid bilayer. Among the macromolecules are proteins. The protein content varies across cell types. For example, mitochondrial inner membranes contain ~76% protein content, while myelin contains ~18% protein content. Individual cells contain many types of membrane proteins—red blood cells contain over 50—and different cell...
81.4K
01:54What are Membranes?
191.7K
A key characteristic of life is the ability to separate the external environment from the internal space. To do this, cells have evolved semi-permeable membranes that regulate the passage of biological molecules. Additionally, the cell membrane defines a cell’s shape and interactions with the external environment. Eukaryotic cell membranes also serve to compartmentalize the internal space into organelles, including the endomembrane structures of the nucleus, endoplasmic reticulum and...
191.7K