Studies on the hydrogen belts of membranes: III. Glycerol permeability of dihydrosphingomyelin‐cholesterol membranes

Abstract

The permeability of an N-oleoyldihydrosphingomyelin bilayer against glycerol was similar to that of a bilayer of phosphatidylcholine with identical effective hydrophobic chain length. Cholesterol at 1:1 molar ratio reduced the permeability, and also reduced the energy of activation of glycerol penetration, an effect not found for diesterphosphatidylcholine with cholesterol. The higher level of the ground state of the entropy of activation for permeability can be interpreted in terms of a hydrogen belt model which postulates lipid-lipid hydrogen bonding in membranes and explains the effect found as a disturbance of the hydrogen belt structure. Dihydrosphingomyelin can be considered to function as an "extender" in the hydrogen belt network.

Plasma Sphingomyelins are Associated with Cognitive Progression in Alzheimer's Disease

“…DHSM influences lipid-lipid hydrogen bonding and increases the order in lipid bilayers by increasing the lateral packing density and stability of membrane microdomains [36]. These biophysical effects can modify the location and function of membrane located receptors and signaling proteins with implications for subsequent signaling events (see [6] for a further discussion of sphingolipids and cellular signaling).…”

The Influence of Hydrogen Bonding on Sphingomyelin/Colipid Interactions in Bilayer Membranes

“…The role of hydrogen bonding in the stability and properties of membranes was suggested in the 1970s (5)(6)(7). Early 1 H and 31 P NMR spectroscopy studies, comparing SM and phosphatidylcholine (PC) bilayers, suggested that differences observed in proton line widths, spin lattice relaxation times, and chemical shifts were due to both inter-and intramolecular hydrogen bonding in the SM bilayers (8).…”