Resveratrol induces chain interdigitation in DPPC cell membrane model systems

Area of Science:

• Biophysics
• Membrane Biophysics
• Lipid Bilayer Dynamics

Background:

• Resveratrol, a natural polyphenol, exhibits diverse therapeutic properties.
• Lipid membranes are key targets for resveratrol's biological actions.
• Understanding resveratrol-membrane interactions is crucial for its therapeutic applications.

Purpose of the Study:

• To investigate the interaction of resveratrol with dipalmitoylphosphatidylcholine (DPPC) lipid bilayers.
• To elucidate the effects of resveratrol on membrane structure, fluidity, and phase transitions.
• To determine the preferred binding site and structural role of resveratrol within the lipid bilayer.

Main Methods:

• Electron Spin Resonance (ESR) spectroscopy of chain-labeled lipids.
• Calorimetry and X-ray diffraction for structural analysis.
• Molecular docking simulations to predict binding interactions.

Main Results:

• Resveratrol restricts lipid tail mobility in the gel phase and alters membrane fluidity.
• It reduces and eliminates the pre-transition temperature, downshifts the main transition temperature, and decreases cooperativity.
• Resveratrol induces a hexagonal packing of untilted lipid chains and promotes an interdigitated Lβi gel phase at high concentrations.

Conclusions:

• Resveratrol significantly modulates DPPC bilayer properties, affecting lipid dynamics and phase behavior.
• The polar headgroup region is identified as the favored anchoring site for resveratrol.
• Resveratrol acts as a spacer, inducing structural changes and promoting the formation of a novel interdigitated gel phase.