Eucalyptus increases ceramide levels in keratinocytes and improves stratum corneum function

Area of Science:

• Dermatology and Skin Biology
• Plant Science
• Biochemistry

Background:

• Stratum corneum function is crucial for skin barrier integrity.
• Ceramides are key lipids within the stratum corneum, essential for its functions.
• Identifying natural compounds that enhance ceramide levels is a therapeutic goal.

Purpose of the Study:

• To identify a plant extract that improves stratum corneum functions.
• To investigate the mechanism by which the extract enhances skin barrier properties.
• To determine if Eucalyptus extract can increase ceramide levels and improve skin hydration and barrier function.

Main Methods:

• In vitro studies using human keratinocytes.
• In vivo studies involving topical application on human subjects with induced dry skin.
• Analysis of ceramide levels, biosynthesis pathways, and gene expression.
• Identification of active components within the Eucalyptus extract.

Main Results:

• Eucalyptus extract significantly increased ceramide levels in keratinocytes and human stratum corneum.
• The extract dose-dependently enhanced ceramide biosynthesis, including glucosylceramide and sphingomyelin.
• Topical application improved stratum corneum water-holding capacity and barrier function.
• Macrocarpal A, a component of the extract, stimulated ceramide synthesis and related enzyme gene expression.

Conclusions:

• Eucalyptus extract effectively improves stratum corneum water-holding and barrier functions.
• Increased ceramide content in the stratum corneum is a likely mechanism for the observed therapeutic effects.
• Macrocarpal A may be the key component responsible for stimulating ceramide synthesis.