PO177 Applicability of stratum corneum tape stripping for the
assessment of the efficacy of cosmetics
Bazela K.1, Debowska R.1, Czajka A.2, Czubaj A.2, Eris I. 1
1Dr.
Irena Eris Centre for Science and Research, Dr. Irena Eris Cosmetic Laboratories, ul. Puławska 107A, Warsaw, Poland, 2Laboratory of Electron Microscopy, Faculty
of Biology, Warsaw University, Poland
Introduction
The outermost skin layer, the stratum corneum
(SC), can be removed sequentially by repeated
application of appropriate adhesive tapes. SC tape
stripping is a relatively non invasive frequently used
method to investigate the structure, properties and
function of SC in vivo.
In this study we used SC tape stripping method to
examine the efficacy of cosmetic products. We
studied the effect of cosmetic treatment on
stratum corneum oxidized proteins and
hydrophobic lipids.
Materials & Methods
The study was conducted on 10 female volunteers
aged between 30 and 55 years. SC was collected
from the cheeks of volunteers by adhesive tape
stripping before and after 14 days of once-daily
applications of the tested cosmetic product. The
study group was divided in two: one (5 subjects)
applied a day face cream rich in antioxidants .To
assess the level of oxidized proteins the adhesive
disc samples taken from the volunteers were
labeled using a solution of fluorescein-5thiosemicarbazide (FTZ), a specific label for
carbonyl groups [1]. The second group (5 subjects)
applied a night face cream rich in emollients . To
assess the level of hydrophobic lipids, corneocytes
were extracted from adhesive discs and the lipids of
the cornified cell envelope were stained with Nile
red [2]. The fluorescence of each sample was
observed using a confocal microscope (Nikon
Eclipse A1).
1. Fujita H., Hirao T., Takahashi M. A simple and non-invasive visualization for
assessment of carbonylated protein in the stratum corneum. Skin Res Technol
2007; 13: 84-90.
2. Hirao T., Denda M., Takahashi M. Identification of immature cornified
envelopes in the barrier-impaired epidermis by characterization of their
hydrophobicity and antigenicities of the components. Exp Dermatol 2001;
10:35-44.
A
B
Figure 1. SC carbonylated proteins visualization
before (A) and after (B) cosmetic treatment
Results
The stratum corneum is continuously exposed to external
oxidative stress that results e.g. in the carbonyl
modification of proteins. In our study we revealed lower
stratum corneum carbonylated protein levels after the
application of the tested formula. These results suggest
that the tested product had antioxidative potential and
may contribute to skin defense against reactive oxygen
species.
A – high fluorescence intensity indicates a high level of
oxidized proteins, B – lower fluorescence
intensity indicates a decrease in the oxidized proteins
level
A
B
Figure 2. SC hydrophobic lipids visualization before
(A) and after (B) cosmetic treatment
A – low fluorescence intensity indicates a low level of
hydrophobic lipids, B – higher fluorescence
intensity indicates an increase in the lipids level
Results
We also examined hydrophobic lipids of stratum corneum
samples and we showed that the level of hydrophobic
lipids was higher after 14 days of using the cream rich in
emollients . However, lipids extraction from adhesive
discs and its visualization by Nile red staining is more
difficult and so to quantify the lipids level we
recommend the measurement of the flurescence of
images.
Our results show that the cosmetic treatment may
contribute to preserving the organization of the stratum
corneum lipids responsible for maintaining barrier
function of the skin.
Conclusion
Stratum corneum tape stripping is a simple and cost effective method to study the in vivo efficacy of
different cosmetic treatment. We demonstrated that the effect of cosmetics on skin antioxidant defense
system and barrier function qualities can be easily examined by SC tape stripping and confocal microscopy. In
vivo study of the effect of cosmetics on structural and functional changes of the skin allows for objective
assessment of cosmetic treatment.