Objective

Evaluate the effect of a glycerol/petrolatum-based emollient (G/P-emollient) cream on the lipid profiles of the stratum corneum (SC) and its potential impact on skin barrier function.

Study

Ex vivo and in vitro study using isolated human SC and a reconstructed human epidermis (RHE) model.

Lipid organization was analyzed using X-ray diffraction (SAXS and WAXS), and shotgun lipidomics analysis was performed to quantify ceramide (CER) classes and chain lengths.

Outcome Measures

• SC lipid organization analyzed by X-ray diffraction.
• Changes in inter-bilayer lipid distances and crystalline lattice type.
• Quantification of CER classes and their chain lengths using lipidomics.
• Changes in specific CER ratios (NP/NS and AP/AS) involved in inflammatory skin conditions.

Results

The cream exhibited a lipid organization similar to that of the SC (orthorhombic and hexagonal lattices).

It penetrated deep SC layers without altering its lamellar structure.

Increased long-chain CERs (>42 carbons) and decreased short-chain CERs (<42 carbons).

Increased acyl-CER classes (CER EOS, EOH, EOP, EOdS) and CER NP, which is reduced in dry skin.

Changes in NP/NS and AP/AS ratios, suggesting a beneficial effect on lipid imbalances observed in inflammatory conditions such as atopic dermatitis.

Conclusion

The G/P-emollient cream favorably modifies SC lipids, balances CER levels and ratios, and potentially improves skin barrier function, which may be beneficial in inflammatory skin conditions such as atopic dermatitis.