Compendium of the most significant studies with reference to properties, intake, effects.

Yokose U, Ishikawa J, Morokuma Y, Naoe A, Inoue Y, Yasuda Y, Tsujimura H, Fujimura T, Murase T, Hatamochi A. The ceramide [NP]/[NS] ratio in the stratum corneum is a potential marker for skin properties and epidermal differentiation. BMC Dermatol. 2020 Aug 31;20(1):6. doi: 10.1186/s12895-020-00102-1.

Abstract. The objective of this study was to identify a new marker to evaluate skin properties and epidermal differentiation in SC not only in barrier-disrupted skin but also in healthy skin.

Danby SG, Brown K, Higgs-Bayliss T, Chittock J, Albenali L, Cork MJ. The Effect of an Emollient Containing Urea, Ceramide NP, and Lactate on Skin Barrier Structure and Function in Older People with Dry Skin. Skin Pharmacol Physiol. 2016;29(3):135-47. doi: 10.1159/000445955.

Abstract. This study aimed to compare the effect of a commercially available emollient containing 5% urea, ceramide NP and lactate (test emollient) to an alternative emollient without these additives (control emollient) on the properties of the skin barrier in older people. 

Sahle FF, Lange S, Dobner B, Wohlrab J, Neubert RH. Development and validation of LC/ESI-MS method for the detection and quantification of exogenous ceramide NP in stratum corneum and other layers of the skin. J Pharm Biomed Anal. 2012 Feb 23;60:7-13. doi: 10.1016/j.jpba.2011.10.032.

Abstract. Ceramides (CERs) are integral parts of the intercellular lipid lamellae of the stratum corneum (SC), which provide the barrier function of the skin.

Ishida K, Takahashi A, Bito K, Draelos Z, Imokawa G. Treatment with Synthetic Pseudoceramide Improves Atopic Skin, Switching the Ceramide Profile to a Healthy Skin Phenotype. J Invest Dermatol. 2020 Sep;140(9):1762-1770.e8. doi: 10.1016/j.jid.2020.01.014.

Abstract. Little is known about the pathophysiological linkages between altered ceramide profiles in the stratum corneum (SC) of patients with atopic dermatitis and their impaired skin barrier and water-holding functions. We studied those characteristics following topical treatment with a designed synthetic pseudoceramide (pCer) and analyzed that pathophysiological linkage by microanalyzing ceramides using normal phase liquid chromatography-electrospray ionization mass spectrometry.

Schmitt T, Lange S, Sonnenberger S, Dobner B, Demé B, Langner A, Neubert RHH. The long periodicity phase (LPP) controversy part I: The influence of a natural-like ratio of the CER[EOS] analogue [EOS]-br in a CER[NP]/[AP] based stratum corneum modelling system: A neutron diffraction study. Biochim Biophys Acta Biomembr. 2019 Jan;1861(1):306-315. doi: 10.1016/j.bbamem.2018.06.008.

Abstract. This study used neutron diffraction to investigate a ceramide-[NP] C24/[AP] C24 /[EOS]-br C30/cholesterol/lignoceric acid (0.6: 0.3: 0.1: 0.7: 1) based stratum corneum modelling system.

Schmitt T, Lange S, Dobner B, Sonnenberger S, Hauß T, Neubert RHH. Investigation of a CER[NP]- and [AP]-Based Stratum Corneum Modeling Membrane System: Using Specifically Deuterated CER Together with a Neutron Diffraction Approach. Langmuir. 2018 Jan 30;34(4):1742-1749. doi: 10.1021/acs.langmuir.7b01848.

Abstract. Neutron diffraction was used as a tool to investigate the lamellar as well as molecular nanostructure of ceramide-[NP]/ceramide-[AP]/cholesterol/lignoceric acid model systems with a nativelike 2:1 ratio and a 1:2 ratio to study the influence of the ceramide-[AP].