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Neutron Spin Echo Spectroscopy as a Unique Probe for Lipid Membrane Dynamics and Membrane-Protein Interactions
Published on: May 27, 2021
NSAIDs interactions with membranes: a biophysical approach.
Cláudia Nunes1, Gerald Brezesinski, Catarina Pereira-Leite
1REQUIMTE, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua Aníbal Cunha, Porto, Portugal.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 28, 2011
Summary
Non-steroidal anti-inflammatory drugs (NSAIDs) interact with cellular membranes, with interactions varying significantly based on pH. This pH-dependent interaction influences drug effects on membrane-associated enzymes and gastrointestinal side effects.
Area of Science:
- Biophysics
- Pharmacology
- Materials Science
Background:
- Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for pain and inflammation.
- Understanding NSAID interactions with cell membranes is crucial for elucidating their therapeutic effects and side effects.
- Cellular membrane properties and drug ionization states are influenced by pH, particularly in inflamed tissues.
Purpose of the Study:
- To investigate the interaction of four NSAIDs (nimesulide, indomethacin, meloxicam, piroxicam) with model cell membranes.
- To evaluate the influence of different pH conditions (physiological and inflammatory) on these drug-membrane interactions.
- To correlate drug-membrane interactions with potential effects on membrane-associated enzymes and gastrointestinal side effects.
Main Methods:
- Utilized liposomes, monolayers, and supported lipid bilayers composed of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC).
- Employed biophysical techniques including fluorescence anisotropy, surface pressure-area isotherms, Infrared Reflection-Absorption Spectroscopy (IRRAS), and Atomic Force Microscopy (AFM).
- Assessed membrane microviscosity, DPPC phase transitions, NSAID adsorption/penetration, monolayer structure, and bilayer surface topography.
Main Results:
- NSAIDs demonstrated significant interactions with lipid membranes under both physiological (pH 7.4) and inflammatory (pH 5.0) conditions.
- Membrane microviscosity and DPPC phase transitions were affected by NSAID presence.
- Drug-membrane interactions were found to be strongly dependent on the medium's pH, influencing both membrane structure and NSAID ionization state.
Conclusions:
- The pH of the environment is a critical factor in NSAID-membrane interactions.
- Understanding these pH-dependent interactions is key to predicting NSAID efficacy and gastrointestinal side effects.
- The study provides detailed insights into drug-membrane interactions, aiding in the comprehension of NSAID mechanisms of action and adverse effects.
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