Effect of a Basic Skin Care Product on the Structural Strength of the Skin

The main aim of this study is to investigate in a suction blister model, whether the use of a basic skin care formulation increases the mechanical integrity/adhesion of the dermo-epidermal junction.

The process of aging involves numerous structural and functional changes also affecting the skin. The skin fulfills a variety of protective and regulatory functions. Compared to other organs, the skin is constantly exposed to harmful environmental influences. Besides intrinsic factors these external factors may accelerate skin aging. Due to its ageing-related loss of functional capacity the skin becomes susceptible to develop adverse skin conditions and dermatological diseases (e.g. skin dryness, fungal infections). Especially old aged, care depended, and severely ill individuals are at high risk for developing severe skin injuries and wounds (e.g. decubitus, skin tears) with high social and economic impact. Empirical evidence indicates that the reduced adhesion of the dermal-epidermal junction is a major pathophysiological predictor for these types of injuries.

The suction blister model is an artificial and controlled technique for dermal-epidermal separation along the dermo-epidermal junction (DEJ). Empirical evidence suggests that the time of the dermal-epidermal separation (blistering time) is a measure of the dermo-epidermal adhesion. It has been proposed that the blistering time might be a clinically relevant parameter reflecting the mechanical integrity/stability of the dermo-epidermal junction.

Clinical practice guidelines recommend the use of topical skin care products to reduce the risk for pressure ulcer and skin tear development. However, the underlying working mechanisms of most basic skin care products are poorly understood. It is known that topically applied skin care products exhibit physical and chemical effects on and in the uppermost skin layers (e.g. the stratum corneum). Despite a few well known active ingredients (e.g. retinoids, vitamin C) exhibiting effects in the dermis, a particular skin protective effect of the vast majority of daily basic skin care applications on these deeper skin layers is unknown. The primary objective of this study is to test, whether the use of a basic skin care formulation increases the mechanical integrity/adhesion of the dermo-epidermal junction.

Eligibility Criteria:
Inclusion Criteria:

* Healthy volunteers and/or with stable chronic condition (e.g. controlled hypertension)
* Female,
* 65 to 85 years,
* Caucasian,
* Phototype I to III according to the Fitzpatrick classification,
* Body Mass Index between 20 and 28 kg/m2,
* Non-smoker of at least one year,
* Absence of skin diseases or scars in the skin area of interest,
* Absence of tattoos in the skin area of interest,
* Able to give written informed consent,
* Willing and able to fulfill the study requirements

Exclusion Criteria:

* Known or suspected defect of healing,
* Diabetes mellitus
* Any acute or chronic pathology that may interfere with the trial conduct, from investigator point of view,
* Acute or chronic wounds in the skin area of interest,
* Any skin affection which may interfere with the trial assessment, like urticaria,, psoriasis or scar on investigational areas,
* Medical history of skin cancer,
* History or establishment of diabetes or pre-diabetes,
* Any hyper-sensibility to one of the compounds of the investigational product,
* Any regular treatment which may affect the blood coagulation and hemostasis (anticoagulant medications, NSAID, etc.) before the suction blister induction (Visit 3 and Visit 5), one NSAID to treat headache within four days is allowed
* Any physical treatment (like laser or surgery) on the arms within the last 6 months,
* Use of topical or systemic treatment on the investigational areas within the past 4 weeks (topical hyaluronan, anti-inflammatory drugs, corticoids, retinoids, vitamin C, etc.) that would interfere with assessment and/or investigational treatments,
* Allergy to band-aid or to metals (such as nickel),
* UV sessions or strong sun exposure of the arms during the study period,
* Subject who cannot be contacted easily in case of necessity,
* Current participation in any other clinical study