Effects of cholesterol on bilayers with various degrees of unsaturation of their phospholipid tails under mechanical stress

Lyu, Dongyu; Zhang, Lei; Zhang, Yong

doi:10.1039/d0ra00624f

Cited by 6 publications

(5 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Only 1–2% of the total amount of CHOL resides in the gap in a DPPC vesicle, while 4–6% is in the gap in a DOPC vesicle. These results are in agreement with the previous work showing CHOL’s preference for the gap of bilayers with unsaturated phospholipid tails. ,, …”

Section: Resultssupporting

confidence: 94%

See 1 more Smart Citation

Cholesterol Distribution in Small Unilamellar Vesicles

Wei

Zhang

2022

J. Phys. Chem. B

Self Cite

View full text Add to dashboard Cite

The plasma membrane has heterogeneity, where the constituents are not only asymmetrically distributed between the inner leaflet and the outer leaflet but also laterally organized within each leaflet. There is still an ongoing controversy over the cholesterol distribution between the two leaflets, and it is also significant to explore the lateral flow and localization of cholesterol. The unilamellar vesicle is extensively employed as a simplified model of the plasma membrane in research studies. In this work, we study the spontaneous spatial distribution of cholesterol in the small unilamellar vesicles with a single type of phospholipid as the bilayer backbone through coarse-grained molecular dynamics simulations. The results show that in a spherical vesicle under ambient pressure, cholesterol is more abundant in the inner leaflet than in the outer leaflet. As the vesicle is deformed under pressurization, the net lateral flow of cholesterol in the two leaflets is in the exactly opposite directions, finally leading to a distribution strongly associated with the monolayer curvature. One of the possible explanations for our results is from the point of view of curvature elastic energy. Another possibility is from the point of view of stress: according to the correlation between the cholesterol distribution and the tail angles of lipids, it is suggested that the possible governing mechanism for the distribution of cholesterol in a membrane is to alleviate the mismatch of stress between the two leaflets. Additionally, we obtain the effect of cholesterol infiltration on the bending modulus and the spontaneous curvature of the vesicles.

show abstract

Section: Resultssupporting

confidence: 94%

“…These results are in agreement with the previous work showing CHOL's preference for the gap of bilayers with unsaturated phospholipid tails. 20,41,42 3.2. Distribution of CHOL in the Deformed Vesicles.…”

Section: Distribution Of Chol In the Spherical Vesiclesmentioning

confidence: 99%

Cholesterol Distribution in Small Unilamellar Vesicles

Wei

Zhang

2022

J. Phys. Chem. B

Self Cite

View full text Add to dashboard Cite

show abstract

“…As a spacer, it pushes phospholipid molecules apart and hence increases the average area of headgroups. 28 As opposed to this, it may exert a condensing effect on the packing of phospholipids in liquidcrystalline state. As produced rigid structures reduce the average area of headgroups due to their inability to isomerize into cis and trans configurations.…”

Section: Resultsmentioning

confidence: 99%

“…It has been argued that the insertion of CHL in the bilayers can induce two different effects while changing the average area for headgroups. As a spacer, it pushes phospholipid molecules apart and hence increases the average area of headgroups . As opposed to this, it may exert a condensing effect on the packing of phospholipids in liquid-crystalline state.…”

Section: Resultsmentioning

confidence: 99%

Sugar-based Cryoprotectants Stabilize Liposomal Vesicles by Exhibiting a Cholesterol-like Effect

Sikandar,

Kumar,

Rathod

et al. 2024

Mol. Pharmaceutics

View full text Add to dashboard Cite

Liposomal vesicles tend to fuse and aggregate during lyophilization. To avoid these events, cryoprotectants are added to the dispersion before lyophilization. Herein, we have compared the effect of three commonly used cryoprotectants (mannitol, MTL; trehalose, THL; and β-cyclodextrin, β-CD) upon structural characteristics of liposomes. The formulation was prepared using ethanol injection method, and cryoprotectants were tested at three dose levels (2, 6, and 10 mM). We have elucidated their effect on soy lecithin (SL) liposomes formulated with and without cholesterol (CHL). Characterizations were performed using scattering, thermal, and spectroscopic techniques. CHL molecules interacted hydrophobically with the SL bilayer. In spite of triggering a noticeable increase in the hydrodynamic diameter (about 30 nm), CHL promoted the stabilization of vesicles. Hydrogen bonding interactions were verified by the shift in −OH stretching over 3300−3500 cm −1 . This manifested in an increased phase transition temperature (T m ) of SL liposomes. T m increased further upon incorporation of cryoprotectants, particularly with β-CD. Enthalpic changes were indicative of an affinity interaction between phospholipids and cryoprotectants, regardless of the presence of CHL. β-CD showed concentration-dependent changes in the energetics of this interaction. The affinity of cryoprotectant-liposome interaction has been ranked as β-CD ≫ THL > MNT.

show abstract

“…This is in line with cholesterol's stronger affinity to saturated hydrocarbon chains compared to polyunsaturated lipids. Indeed, other studies on DAPC-cholesterol membranes show that while only 5 mol% of fully saturated DMPC (14:0-14:0) is required to pull cholesterol back up into its upright position, it takes 50 mol% of POPC (16: 0-18:1) to achieve the same effect [79,80].…”

Section: Amphiphilic Additivesmentioning

confidence: 99%

The effects of molecular and nanoscopic additives on phospholipid membranes

Kumarage,

Morris,

Ashkar

2023

Front. Phys.

View full text Add to dashboard Cite

Lipid bilayers—the main matrix of cell membranes—are a paradigm of soft molecular assemblies whose properties have been evolutionarily optimized to satisfy the functional requirements of cells. For instance, lipid bilayers must be rigid enough to serve as the protective barrier between cells and their environment, yet fluid enough to enable the diffusion of proteins and molecular clusters necessary for biological functions. Inspired by their biological multifunctionality, lipid membranes have also been used as a central design element in many practical applications including artificial cells, drug nanocarriers, and biosensors. Whether biological or synthetic, lipid membranes often involve molecular or nanoscopic additives that modulate the membrane properties through various mechanisms. Hence, how lipid membranes respond to additives has justifiably drawn much attention in recent years. This review summarizes findings and observations on different classes of additives and their effects on structural, thermodynamic, elastic, and dynamical membrane properties that are central to biological function or synthetic membrane performance. The review primarily focuses on phospholipids as a major component of cell membranes and a widely used lipid type in synthetic membrane designs.

show abstract

Effects of cholesterol on bilayers with various degrees of unsaturation of their phospholipid tails under mechanical stress

Abstract: The concentration-effect of cholesterol on the mechanical strength of biomembranes weakens as the degree of unsaturation of the phospholipid tails increases.

Cited by 6 publications

References 51 publications

Cholesterol Distribution in Small Unilamellar Vesicles

Cholesterol Distribution in Small Unilamellar Vesicles

Sugar-based Cryoprotectants Stabilize Liposomal Vesicles by Exhibiting a Cholesterol-like Effect

The effects of molecular and nanoscopic additives on phospholipid membranes

Contact Info

Product

Resources

About