Tags

Type your tag names separated by a space and hit enter

Stratum corneum lipid matrix: Location of acyl ceramide and cholesterol in the unit cell of the long periodicity phase.
Biochim Biophys Acta. 2016 08; 1858(8):1926-34.BB

Abstract

The extracellular lipid matrix in the skin's outermost layer, the stratum corneum, is crucial for the skin barrier. The matrix is composed of ceramides (CERs), cholesterol (CHOL) and free fatty acids (FFAs) and involves two lamellar phases: the short periodicity phase (SPP) and the long periodicity phase (LPP). To understand the skin barrier thoroughly, information about the molecular arrangement in the unit cell of these lamellar phases is paramount. Previously we examined the molecular arrangement in the unit cell of the SPP. Furthermore X-ray and neutron diffraction revealed a trilayer arrangement of lipids within the unit cell of the LPP [D. Groen et al., Biophysical Journal, 97, 2242-2249, 2009]. In the present study, we used neutron diffraction to obtain more details about the location of lipid (sub)classes in the unit cell of the LPP. The diffraction pattern revealed at least 8 diffraction orders of the LPP with a repeating unit of 129.6±0.5Å. To determine the location of lipid sub(classes) in the unit cell, samples were examined with either only protiated lipids or selectively deuterated lipids. The diffraction data obtained by means of D2O/H2O contrast variation together with a gradual replacement of one particular CER, the acyl CER, by its partly deuterated counterpart, were used to construct the scattering length density profiles. The acyl chain of the acyl CER subclass is located at a position of ~21.4±0.2Å from the unit cell centre of the LPP. The position and orientation of CHOL in the LPP unit cell were determined using tail and head-group deuterated forms of the sterol. CHOL is located with its head-group positioned ~26±0.2Å from the unit cell centre. This allows the formation of a hydrogen bond with the ester group of the acyl CER located in close proximity. Based on the positions of the deuterated moieties of the acyl CER, CHOL and the previously determined location of two other lipid subclasses [E.H. Mojumdar et al., Biophysical Journal, 108, 2670-2679, 2015], a molecular model is proposed for the unit cell of the LPP. In this model CHOL is located in the two outer layers of the LPP, while CER EOS is linking the two outer layers with the central lipid layers. Finally the two other lipid subclasses are predominantly located in the central layer of the LPP.

Authors+Show Affiliations

Leiden Academic Centre for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, Leiden, The Netherlands.Leiden Academic Centre for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, Leiden, The Netherlands.Leiden Academic Centre for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, Leiden, The Netherlands.Pharmaceutical Science Division, King's College London, London, United Kingdom.Pharmaceutical Science Division, King's College London, London, United Kingdom.Institute Laue-Langevin, Grenoble, France.Leiden Academic Centre for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, Leiden, The Netherlands. Electronic address: bouwstra@chem.leidenuniv.nl.

Pub Type(s)

Journal Article

Language

eng

PubMed ID

27169629

Citation

Mojumdar, E H., et al. "Stratum Corneum Lipid Matrix: Location of Acyl Ceramide and Cholesterol in the Unit Cell of the Long Periodicity Phase." Biochimica Et Biophysica Acta, vol. 1858, no. 8, 2016, pp. 1926-34.
Mojumdar EH, Gooris GS, Groen D, et al. Stratum corneum lipid matrix: Location of acyl ceramide and cholesterol in the unit cell of the long periodicity phase. Biochim Biophys Acta. 2016;1858(8):1926-34.
Mojumdar, E. H., Gooris, G. S., Groen, D., Barlow, D. J., Lawrence, M. J., Demé, B., & Bouwstra, J. A. (2016). Stratum corneum lipid matrix: Location of acyl ceramide and cholesterol in the unit cell of the long periodicity phase. Biochimica Et Biophysica Acta, 1858(8), 1926-34. https://doi.org/10.1016/j.bbamem.2016.05.006
Mojumdar EH, et al. Stratum Corneum Lipid Matrix: Location of Acyl Ceramide and Cholesterol in the Unit Cell of the Long Periodicity Phase. Biochim Biophys Acta. 2016;1858(8):1926-34. PubMed PMID: 27169629.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Stratum corneum lipid matrix: Location of acyl ceramide and cholesterol in the unit cell of the long periodicity phase. AU - Mojumdar,E H, AU - Gooris,G S, AU - Groen,D, AU - Barlow,D J, AU - Lawrence,M J, AU - Demé,B, AU - Bouwstra,J A, Y1 - 2016/05/08/ PY - 2016/04/06/received PY - 2016/05/05/accepted PY - 2016/5/13/entrez PY - 2016/5/14/pubmed PY - 2017/10/27/medline KW - Ceramides KW - Lipid mixtures KW - Long periodicity phase KW - Neutron diffraction KW - Stratum corneum SP - 1926 EP - 34 JF - Biochimica et biophysica acta JO - Biochim Biophys Acta VL - 1858 IS - 8 N2 - The extracellular lipid matrix in the skin's outermost layer, the stratum corneum, is crucial for the skin barrier. The matrix is composed of ceramides (CERs), cholesterol (CHOL) and free fatty acids (FFAs) and involves two lamellar phases: the short periodicity phase (SPP) and the long periodicity phase (LPP). To understand the skin barrier thoroughly, information about the molecular arrangement in the unit cell of these lamellar phases is paramount. Previously we examined the molecular arrangement in the unit cell of the SPP. Furthermore X-ray and neutron diffraction revealed a trilayer arrangement of lipids within the unit cell of the LPP [D. Groen et al., Biophysical Journal, 97, 2242-2249, 2009]. In the present study, we used neutron diffraction to obtain more details about the location of lipid (sub)classes in the unit cell of the LPP. The diffraction pattern revealed at least 8 diffraction orders of the LPP with a repeating unit of 129.6±0.5Å. To determine the location of lipid sub(classes) in the unit cell, samples were examined with either only protiated lipids or selectively deuterated lipids. The diffraction data obtained by means of D2O/H2O contrast variation together with a gradual replacement of one particular CER, the acyl CER, by its partly deuterated counterpart, were used to construct the scattering length density profiles. The acyl chain of the acyl CER subclass is located at a position of ~21.4±0.2Å from the unit cell centre of the LPP. The position and orientation of CHOL in the LPP unit cell were determined using tail and head-group deuterated forms of the sterol. CHOL is located with its head-group positioned ~26±0.2Å from the unit cell centre. This allows the formation of a hydrogen bond with the ester group of the acyl CER located in close proximity. Based on the positions of the deuterated moieties of the acyl CER, CHOL and the previously determined location of two other lipid subclasses [E.H. Mojumdar et al., Biophysical Journal, 108, 2670-2679, 2015], a molecular model is proposed for the unit cell of the LPP. In this model CHOL is located in the two outer layers of the LPP, while CER EOS is linking the two outer layers with the central lipid layers. Finally the two other lipid subclasses are predominantly located in the central layer of the LPP. SN - 0006-3002 UR - https://www.unboundmedicine.com/medline/citation/27169629/Stratum_corneum_lipid_matrix:_Location_of_acyl_ceramide_and_cholesterol_in_the_unit_cell_of_the_long_periodicity_phase_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0005-2736(16)30149-3 DB - PRIME DP - Unbound Medicine ER -