ArticlePDF Available

A Placebo-Controlled Study Demonstrates the Long-Lasting Anti-Aging Benefits of a Cream Containing Retinol, DihydroxyMethylChromone (DMC) and Hyaluronic Acid

Authors:

Abstract

Retinol is an ingredient used in cosmetic products for reducing the appearance of the signs of aging and photo-damage. Currently, most of these products contain 0.1% of retinol. However, at this concentration, some irritation can occur. We have evaluated in vitro and in a clinical study the potential efficacy of a combination of actives to improve the facial skin aging signs while using low concentration of retinol. We demonstrated, in vitro, that a chromone derivative, 5,7-di-hydroxy-2-methyl chromone (DMC), is able to enhance the collagen synthesis in culture of normal human dermal fibroblasts. The enhancement of retinol anti-wrinkle efficacy by DMC was confirmed in a small scale clinical trial. Specifically, a product associating low concentration of retinol (0.04%) and DMC (0.1%) in combination with low mo-lecular weight hyaluronic acid fragments (50,000 Dalton of average molecular weight) has been applied topically for 8 weeks. Clinical results show significant improvement of various signs of facial skin aging such as wrinkles, pigmentary spots, tone unevenness, dullness and the overall photo-damage score. Improvements were still visible 4 weeks after the cessation of the test product application. This study demonstrates that significant lasting improvement of facial skin aging can be obtained with well tolerated low concentration of retinol when adequately formulated with other anti-aging ingredients.
Journal of Cosmetics, Dermatological Sciences and Applications, 2012, 2, 51-59
doi:10.4236/jcdsa.2012.22012
Published Online June 2012 (http://www.SciRP.org/journal/jcdsa)
51
A Placebo-Controlled Study Demonstrates the
Long-Lasting Anti-Aging Benefits of a Cream Containing
Retinol, DihydroxyMethylChromone (DMC) and
Hyaluronic Acid
Thierry Oddos
1
, Romain Roure
2
, James Leyden
3
, Valérie Bruère
2
, Christiane Bertin
2
1
Johnson & Johnson Santé Beauté France, Val-de-Reuil, France;
2
Johnson & Johnson Santé Beauté France, Issy-les-Moulineaux,
France;
3
KGL Inc., Broomall, USA.
Email: toddos@its.jnj.com, rroure@its.jnj.com
Received February 7
th
, 2012; revised March 11
th
, 2012; accepted March 21
st
, 2012
ABSTRACT
Retinol is an ingredient used in cosmetic products for reducing the appearance of the signs of aging and photo-damage.
Currently, most of these products contain 0.1% of retinol. However, at this concentration, some irritation can occur. We
have evaluated in vitro and in a clinical study the potential efficacy of a combination of actives to improve the facial
skin aging signs while using low concentration of retinol. We demonstrated, in vitro, that a chromone derivative, 5,7-
di-hydroxy-2-methyl chromone (DMC), is able to enhance the collagen synthesis in culture of normal human dermal
fibroblasts. The enhancement of retinol anti-wrinkle efficacy by DMC was confirmed in a small scale clinical trial.
Specifically, a product associating low concentration of retinol (0.04%) and DMC (0.1%) in combination with low mo-
lecular weight hyaluronic acid fragments (50,000 Dalton of average molecular weight) has been applied topically for 8
weeks. Clinical results show significant improvement of various signs of facial skin aging such as wrinkles, pigmentary
spots, tone unevenness, dullness and the overall photo-damage score. Improvements were still visible 4 weeks after the
cessation of the test product application. This study demonstrates that significant lasting improvement of facial skin
aging can be obtained with well tolerated low concentration of retinol when adequately formulated with other anti-aging
ingredients.
Keywords: Retinol; DihydroxyMethylChromone; Hyaluronic Acid; Anti-Age; Long-Lasting Effect
1. Introduction
Clinically, facial skin aging is characterized by multiple
features including fine lines, wrinkles, mottled hyper
pigmentation, brown spots, laxity and loss of firmness.
Repeated exposure to solar ultraviolet radiations induces
skin aging signs such as deep wrinkles, loss of firmness
and pigmentary changes [1-4]. These signs of chrono-
logical aging and photo-damage are associated with a
general slow-down of cell renewal in the epidermis and
loss of collagen synthesis in the dermis [5-9]. It was de-
monstrated that exposure of skin cells to sunlight radia-
tion is associated with subclinical inflammation that in-
duces release of degrading enzymes such as collagenase
(Matrix Metalloproteinase-1, MMP1) and gelatinase
(Matrix Metalloproteinase-9, MMP9) that degrades col-
lagen in the dermis [10-12], and with the synthesis and
accumulation of non functional elastin [13-15]. In the
epidermis, chronological and photo aging lead to an
atrophy of the epidermis with a loss of the micro relief as
well as an irregular distribution of melanin [16-18].
Prevention and reduction of the appearance of the
signs of aging on facial skin has been one of the main
challenges in the cosmetic industry. Several categories of
solutions, based on the use of active ingredients, have
been developed. Among them, retinoids, a family of
compounds derived from vitamin A, or molecules which
interact with retinoid receptors and produce similar bio-
logical effects, decrease the severity of skin aging [19-
22]. Retinoids counteract some of the physiological causes
leading to the appearance of skin aging signs. For exam-
ple, retinoids stimulate epidermal cells proliferation
through the release of Heparin Binding-Epidermal Growth
Factor (HB-EGF), and inducing epidermal thickening
[23-25]. They also enhance collagen synthesis and func-
tional elastin fibers accumulation in the dermis while
they prevent the over-expression of matrix metallopro-
teinase through the interference with the jun/fos AP1
inflammation pathway [11,26]. However, the cosmetic
use of retinoids is limited due to their potential to cause
Cop
yright © 2012 SciRes. JCDSA
A Placebo-Controlled Study Demonstrates the Long-Lasting Anti-Aging Benefits of a Cream Containing Retinol,
DihydroxyMethylChromone (DMC) and Hyaluronic Acid
52
skin irritation [27-29].
Hyaluronic Acid (HA) is a major component of the
extracellular matrix of the dermis. It is a high-molecular-
weight glycosaminoglycan composed of glucuronic acid
and N-acetylglucosamine disaccharide repeats. It is known
to bind water, and it has been used for decades as a
moisturizing ingredient in cosmetic products. Recently, it
has been shown that HA could enhance keratinocyte pro-
liferation through CD44 receptor stimulation. Moreover,
CD44 expression is reduced with exposure to UV light.
This reduced expression of CD44 can be reversed by
retinoids such retinol or retinaldehyde [30,31].
In this article, we describe the combination of retinol
with Di-hydroxy Methyl Chromone (DMC), an active
ingredient that, in our in vitro screening, showed additive
effect on retinol-induced gene expression in human kera-
tinocyte, and with low molecular weight HA, to deliver
benefit on multiple signs of skin aging without signifi-
cant signs of irritation. The beneficial effects of this com-
bination of ingredients were evidenced in a double-blind
placebo-controlled two-month clinical study. The results
of the study show a remaining effect during the first 4
weeks after the cessation of the treatment.
2. Materials and Methods
2.1. Proof of Principle
2.1.1. In Vitro Studies
2.1.1.1. Keratinocyte Culture
Keratinocytes (Lonza, Verviers Belgium) were seeded at
10,000 cells per well in six wells plate and cultivated in
KBM2 medium (Lonza, Verviers, Belgium) supplemented
with Bovine Pituitary extract, human Epidermal Growth
Factor, insulin, hydrocortisone, transferrin and epineph-
rine (Lonza) and antibiotics. Test ingredients were intro-
duced in the medium and keratinocyte cultures were in-
cubated during 48 hours at 37˚C in a water saturated at-
mosphere containing 5% CO
2
. Then cells were detached
from plastic by trypsination. After several rinsing in
phosphate buffer saline (pH 7.2), cells were counted and
then pelleted in microtube. RNA were extracted using a
RNeasy Plus mini kit (Qiagen, Courtaboeuf, France) and
the concentration of total RNA was determined by mea-
suring the optical density at 260 nm. The purity of the
RNAs was assessed by measuring A260/A230 and A260/
A280 ratios.
2.1.1.2. Analysis of Gene Expression by Real Time
Quantitative Polymerase Chain Reaction (QPCR)
1 µg of total RNA was reverse transcribed to generate
first-strand cDNA using ImProm-II Reverse Transcrip-
tion system (Promega, Charbonnnières, France) with ran-
dom hexamers as suggested by the manufacturer instruct-
tions. As controls, parallel reactions were run in the ab-
sence of reverse transcriptase or in the absence of input
RNA to assess any genomic DNA contamination. Real-
time QPCR amplification was carried out using the Bril-
liant SYBR Green QPCR Mix (Stratagene, Amsterdam,
Netherlands) in Mx3000p detection system (Stratagene).
Each sample was analyzed in duplicate along with stan-
dard and no-template controls. PCR parameters were
95˚C for 10 minutes, 40 cycles at 95˚C for 15 sec, 60˚C
for 1 minute and 72˚C for 30 sec. RNA concentrations
were determined by determining Cycle Threshold (CT)
for each sample and subsequently using the 2-ΔΔCT
method. RNA levels were further corrected with the 18S
gene cDNA signal for variations in amounts of input
RNA. Statistical analysis was done with the Student t-test
(p 0.05).
2.1.1.3. Fibroblasts Culture and Collagen Synthesis
Assay
50,000 fibroblasts isolated from human abdominal skin
biopsies were seeded in 24 wells multiplate in DMEM
(Invitrogen, Cergy Pontoise, France) with 10% fetal calf
serum (FCS) (ATGC, Marne la Vallée France) with anti-
biotics and incubated at 37˚C in a humidified atmosphere.
72 hours later supernatants were replaced with DMEM
containing 2% FCS, 50 µg/ml β-aminopropionitrile, 50
µg/ml ascorbic acid, 3 - 4 µg/ml α-ketoglutarate (Sigma-
Aldrich, Saint Quentin Fallavier, France) and the test
product. Half of the wells (n = 4) received also 5 µCi of
tritiated proline (Amersham-GE Healthcare, Orsay, France)
for synthesis rate incorporation. The other half (n = 4)
was treated identically with the exception of radioactive
proline. These cells were counted to assess the number of
cells per well. 72 hours later, supernatants were recovered
and precipitated with 20% trichloro-acetic acid (TCA)
(Sigma-Aldrich). Pellet were rinsed twice with 5% TCA
and dissolved in sodium hydroxide 0.05 N. Protein solu-
tions were treated with purified collagenase Type III
(Sigma-Aldrich (Unit/ml) and reaction was stopped by
precipitating the proteins with TCA 15% and tannic acid
0.75%. Then the radioactivity contained in the super-
natant corresponding to the collagen fraction was counted
on a β-scintillation counter (Perkin Elmer, Courtaboeuf,
France). Results were expressed as dpm in collagenic
fraction per 1000 cells and percentage of stimulation was
calculated as followed:

% of stimulation synthesis rate in sample synthesis rate in control synthesis rate in control 100

.
Copyright © 2012 SciRes. JCDSA
A Placebo-Controlled Study Demonstrates the Long-Lasting Anti-Aging Benefits of a Cream Containing Retinol,
DihydroxyMethylChromone (DMC) and Hyaluronic Acid
53
Statistical analysis was done with the Student t-test (p
0.05).
2.1.2. In Vivo Proof of Principle
A double blind, randomized clinical study was performed
to demonstrate the additive efficacy of DMC when com-
bined with 2 different percentages of retinol. The study
was conducted from March to June of 2006.
The subjects applied the products once a day, in the
morning, for 12 weeks. Products were applied
ad libitum,
randomly, to a split face. The three test products were
randomly distributed between subjects according to a
split face mode.
2.1.2.1. Subjects
34 subjects aged from 42 to 59 years old, with skin pho-
totypes I-IV according to Fitzpatrick’s classification,
were involved in this study. The volunteers were in good
health without any skin condition. Each volunteer signed
an informed consent form before participating to the
study. Two subjects withdrew from the study due to cu-
taneous reactions to the products.
2.1.2.2. Products
The products contained a combination of active ingre-
dients: retinol, hyaluronic acid and DihydroxyMethyl-
Chromone (DMC). The three test products contained
either 0.04% retinol or 0.1% retinol or 0.04% retinol and
0.1% DMC.
2.1.2.3. Measurements
A clinical assessment of the wrinkles was performed at
baseline (T0) and after 12 weeks (T12) of products use,
using a 12 cm-visual analog scale by an expert grader.
The results are given as percentage of improvement from
baseline. For the comparison between products, the sta-
tistical analysis was performed on the differences be-
tween T12 and T0. A paired Student’s
t-test was done to
compare the individual scores at each follow-up session
relative to their respective baselines for each treatment.
2.2. Clinical Study
A double blind, randomized, placebo-controlled study
was performed to assess the efficacy of a formula con-
taining a combination of three active ingredients: retinol
0.04%, DMC 0.1% and HA 0.1%, with a special focus on
the immediate and lasting effect on signs of facial pho-
todamage. The study was conducted from March to July
of 2007.
Randomization was performed by the sponsor and
neither the investigator nor the volunteers knew which
product was used. The investigator followed the general
guidelines recommended in Good Clinical Practices (GCP)
and Good Laboratory Practices (GLP).
There were 2 parallel groups, each panelist applying
one product (active or placebo) on face and neck, ac-
cording to the randomization. One month before the be-
ginning of the study, all volunteers had to stop using any
anti-aging products and applied, in the evening, a basic
moisturizing cream that they continued to apply for the
total duration of the study. During the 8-week application
period, the panelists applied the product (active or pla-
cebo); once a day, in the morning. Both products were
applied ad libitum. After the eight weeks of product ap-
plication, all the volunteers kept using the moisturizing
cream for 4 weeks (regression period). A sample daily
diary form was provided to each subject. They indicated
the time of product application during the entire study.
Subjects were evaluated 4 weeks after discontinuation of
treatment to determine if changes persisted. Prolonged
exposure to the sun had to be avoided during the entire
study including the preconditioning phase. If prolonged
sun exposure was unavoidable, subjects were required to
use a SPF 50+ sunscreen provided by the sponsor.
2.2.1. Subjects
87 (eighty seven) healthy women volunteers were re-
cruited from a pool of women who meet the inclusion
criteria. To be included in the study, the subjects had to
be between 35 to 60 years of age (min = 37 y.o. and max
= 60 y.o.) and had to present signs of photodamage
(score superior or equal to 4 at baseline on a 10-point
scale). All volunteers signed an informed consent. Two
subjects withdrew for personal reasons unrelated to the
study. The population was split into two groups, 44 (forty
four) volunteers applied the product and 43 (forty three)
the placebo, during the 8-week treatment period.
2.2.2. Products
The active product contained a combination of active
ingredients: retinol, hyaluronic acid and DihydroxyMe-
thylChromone (DMC). The placebo, a basic moisturizer,
was an oil in water emulsion without the active ingre-
dients.
2.2.3. Measurements
The measurements employed were clinical grading of
aging signs and digital photography. These measurements
were performed at baseline (T0), then after four weeks
(T4) and eight weeks (T8) of daily application as well as
after the regression period (T12) to assess the residual
effect.
More specifically, at each time point, the expert der-
matologist examined the panelists and graded their face
for a series of attributes: forehead wrinkles, crow’s feet
wrinkles, crow’s feet fine lines, under eye wrinkles,
cheek wrinkles, brown spots, lack of skin texture, lack of
Copyright © 2012 SciRes. JCDSA
A Placebo-Controlled Study Demonstrates the Long-Lasting Anti-Aging Benefits of a Cream Containing Retinol,
DihydroxyMethylChromone (DMC) and Hyaluronic Acid
54
skin radiance, lack of evenness of skin tone, lack of skin
softness, lack of skin smoothness and overall photoda-
mage. The investigator used a 10 points structured scale
with the following severity ranking: 0 = none; 1 to 3 =
mild; 4 to 6 = moderate and 7 to 9 = severe.
Also, digital photographies of frontal/side shot of the
face were taken using standardized equipment and pro-
cedures provided by the Sponsor. The panelists were
asked to present a neutral face expression with eyes open
when imaging under visible light and eyes closed for
other types of light.
2.2.4. Statistical Analysis
The data set was analyzed by comparing the changes that
occurred within each treatment group, from Baseline to
each consequent timepoint. Normality of sample distri-
bution was verified using the one-sample Kolmogorov-
Smirnov test. According to this test, a paired Student’s
t-test (normal distribution) or a Wilcoxon signed rank
test was done to compare the individual scores at each
follow-up session relative to their respective Baseline for
each treatment.
In addition, groups were compared based on the net
change from Baseline. Normality of distribution (one-
sample Kolmogorov-Smirnov test) and variance equality
(F-test) were verified. According to these previous tests,
comparisons were done using the adequate test (either
Independent Student’s
t-test with equal or unequal va-
riance for normal distribution or Wilcoxon rank sum
test).
Throughout the analysis, unless otherwise specified, a
two tailed p 0.05 was taken as the level of significance.
The values reported in the results are expressed as arith-
metic mean ± standard error of the mean (SEM). All sta-
tistical tests were performed using the software Matlab
®
.
3. Results
3.1. Preliminary Assessment of the Anti Aging
Efficacy of Retinol and DMC Combination
3.1.1. In Vitro
The effects of DMC were assessed using different end
points. Treatment of human dermal fibroblasts in culture
by DMC induced a significantly higher level of collagen
synthesis compared to non treated control, as measured
by the incorporation of tritiated proline in the extra cel-
lular collagenic fraction (
Table 1(a)). The stimulation
obtained with DMC 0.1 µg/ml and 1 µg/ml (46 ± 2.2
dpm/10
3
cells and 46.2 ± 5.8 dpm/10
3
cells respectively)
were similar to the one obtained with tumor growth fac-
tor
β-1 (TGF β1) (46.5 ± 0.5 dpm/10
3
cells ) and signifi-
cantly higher than the non treated control (34.7 ± 4.1
dpm/10
3
cells ).
When tested in association with retinol in skin ex-
plants model, DMC slightly increased the steady state
level of retinol-induced HB-EGF and CRABP2 mRNA,
two markers of retinol activity in epidermis of human
skin explants, although this effect was not statistically
significant (
Table 1(b)).
3.1.2. In Vivo Proof of Principle
After 12 weeks of products application, the crow’s feet
wrinkles were significantly improved versus baseline with
retinol 0.04% (p = 0.015), retinol 0.1% (p = 6 × 10
–5
),
retinol 0.04% + DMC 0.1% (p = 0.00012). The addition
of DMC to retinol 0.04% resulted in a significantly better
efficacy compared to retinol 0.04% and similar to the ef-
ficacy of the product containing retinol 0.1% (
Table 2).
3.2. Clinical Study Results
3.2.1. During the Application Period
Wrinkles and fine lines were significantly improved with
the active product versus baseline, the score differences
varying from 0.23 to 1.03 (on a 10-point scale), after 4
and 8 weeks with p-values from 1.86 × 10
–3
to 6.74 ×
10
–10
, while no significant improvement of wrinkles was
observed with the placebo. Moreover, the effect of the
Table 1. (a) Effect of DMC on collagen synthesis in human
dermal fibroblasts culture. Collagen synthesis was mea-
sured by the incorporation of tritiated proline in the ex-
tracellular collagenic fraction. Results are expressed as dpm
in collagenic fraction per 1000 cells; (b) Effect of the asso-
ciation retinol and DMC on the expression of retinoic ac-
tivity marker in keratinocytes cultures. The expression of
HB-EGF and CRABPII genes were measured after 48 hours
of treatment by real time quantitative PCR.
(a)
Test product Collagen synthesis.
Control
34.7 4.1
TGFβ 1 ng/ml
49.5 0.3
*
DMC 0.1 µg/ml
46 2.2
*
DMC 1 µg/ml
46.2 5.8
*
*
Significant difference in t-test p < 0.05.
(b)
Test product
Expression of CRABP2
mRNA (% versus control)
Expression of HB-EGF
mRNA % versus control
Control
100 5 100 10
Retinol 0.04%
325 16 188 3
+DMC 0.1%
440 40 268 35
Retinol 0.1%
561 86 436 29
+DMC 0.1%
747 144 791 116
All results showed significant difference in t-test p < 0.05 vs. control.
Copyright © 2012 SciRes. JCDSA
A Placebo-Controlled Study Demonstrates the Long-Lasting Anti-Aging Benefits of a Cream Containing Retinol,
DihydroxyMethylChromone (DMC) and Hyaluronic Acid
55
Table 2. In vivo proof of principle: Clinical grading of the
crow’s feet wrinkles using a 12 cm visual analog scale.
Test product
Retinol
0.1%
Retinol
0.04%
Retinol 0.04% +
DMC 0.1%
Baseline 3.1 (0.5) 2.7 (0.4) 3.9 (0.5)
Week 12 1.9 (0.3) 2.1 (0.3) 2.2 (0.3)
*
Difference 1.2 0.6 1.7
These results are expressed as arithmetic means and standard deviation.
Values in bold indicate significant improvement compared to baseline (p <
0.05).
*
Difference between retinol 0.04% + DMC 0.1% and retinol 0.04% is
significant (p < 0.05).
active product on wrinkles and fine lines was signifi-
cantly higher relative to that of the placebo, as soon as 4
weeks, with p-values from p = 8.53 × 10
–3
to p = 6.6 ×
10
–15
. Parameters related to skin tone and texture were
also significantly improved versus both baseline and pla-
cebo.
Specifically, the assessment of brown spots showed
score differences relative to T0 of 1.10 and 1.34 at T4
and T8, respectively. Radiance was improved by 1.87
and 2.05 after T4 and T8, while evenness skin tone in-
creased from T0 by 1.3 and 1.55 at T4 and T8, respec-
tively. All results were highly significant with p values
varying from 1.12 × 10
–8
to 6.66 × 10
–9
(Figure 1).
Finally, grading of the overall photo-damage showed
also a significant improvement with change in score val-
ues versus baseline of 0.86 after 4 weeks and 0.97 after 8
weeks (p < 10
–6
). These improvements were significantly
higher than those obtained with the placebo (
Table 3).
3.2.2. At the End of the Regression Period
Clinical grading was also performed 4 weeks after the
end of the treatment with the active product. Results
showed that 4 weeks after stopping the product applica-
tion, improvement versus T0 was significantly main-
tained for crow’s feet fine lines (1.12), crow’s feet wrin-
kles (0.64), forehead wrinkles (0.66), under eye wrinkles
(0.46) and cheek wrinkles (0.51) for panelists that used
the active product, with p-values between 5 × 10
–13
and
2.9 × 10
–5
. Only crow’s feet fine lines improvement was
significantly maintained with the placebo (p = 3.91 ×
10
–2
).
The differences between the efficacy of the active and
placebo at the end of the regression period were still sig-
nificant (p < 10
–5
) for parameters such as crow’s feet fine
lines, crow’s feet wrinkles, forehead wrinkles, under eye
wrinkles and cheek wrinkles (
Figure 2).
The differences of the active product efficacy between
T0 and T12 on the other signs of skin aging, such as
brown spots (1.38), overall photodamage (1.11), radiance
(2.38), and evenness skin tone (1.74) were still signifi-
cantly improved, with p-values inferior to 10
–7
. When the
Figure 1. Pictures of eye area (crow’s feet area) at baseline
(top) and after 8 weeks (bottom).
placebo was used, the overall photodamage, radiance and
evenness skin tone were also significantly improved. How-
ever, significant differences between active and placebo
efficacy were still noticed on brown spots (p = 3.06 ×
10
–12
), overall photodamage (p = 1.39 × 10
–10
), skin ra-
diance (p = 4.34 × 10
–13
) and evenness skin tone (p =
2.49 × 10
–7
) (Table 3).
4. Discussion
Retinoids are a family of compounds structurally related
to retinol (vitamin A). They play an important role on
epithelium proliferation and differentiation as well as
exerting effects on the dermal matrix. Different studies
have demonstrated the efficacy of topical tretinoin to
improve photodamage. However, its use as topical treat-
ment is complicated due to its irritation potential. On the
other hand, retinol shows potential to reduce the signs of
facial aging but with a much better tolerance profile. Re-
cently Kafi
et al. [32] demonstrated that topical applica-
Copyright © 2012 SciRes. JCDSA
A Placebo-Controlled Study Demonstrates the Long-Lasting Anti-Aging Benefits of a Cream Containing Retinol,
DihydroxyMethylChromone (DMC) and Hyaluronic Acid
Copyright © 2012 SciRes. JCDSA
56
Table 3. In vivo clinical grading by the investigator of the
other signs of ageing on 10-points scales (from 0 = none to 9
= severe).
chr
onological aging. In the past, we have demonstrated
that lower concentration of retinol (0.1%) also delivers
beneficial result on skin photoaging signs [33,34]. Even
more, in the study described in this paper, we have de-
monstrated that the clinical efficacy of retinol could be
achieved with a concentration of retinol as low as 0.04%
by using it in combination with a chromone derivative
and low molecular weight fragments of hyaluronic acid.
The complementary effect between retinol and the DMC
was confirmed in a small scale clinical study in which
the association of retinol and DMC delivered a better
clinical efficacy on wrinkles than retinol alone. It has to
be noted that DMC tested alone at the same concentra-
tion (0.1%) in the same formula did not deliver any im-
provement on wrinkles (data not shown).
Ex vivo, topi-
cal application of retinol on skin has induced both
keratinocyte proliferation and accumulation of extracel-
lular matrix components such as pro-collagen and glu-
coaminoglycan [32]. We have previously showed that
improvement of fine lines by retinol was correlated to its
capacity to increase cell proliferation in the epidermis. It
was not the case with the deep wrinkle suggesting that
the wrinkle improvement by retinol might come from an
effect on the extracellular matrix. Therefore, it can be
assumed that the effect of DMC on retinol induced im-
Time (weeks)
Brown
spots
Overall
photo damage
Skin
radiance
Evenness
skin tone
T0
Active (n = 44) 3.5 (0.2) 5.1 (0.1) 4.7 (0.1) 4.3 (0.1)
Placebo (n = 43) 3.1 (0.2) 4.9 (0.1) 4.5 (0.1) 4.3 (0.1)
T4
Active (n = 43)
2.4 (0.2)
*
4.2 (0.1)
*
2.8 (0.1)
*
3.0 (0.1)
*
Placebo (n = 42) 3.1 (0.2) 4.8 (0.1)
3.8 (0.1) 3.8 (0.1)
T8
Active (n = 43)
2.2 (0.2)
*
4.1 (0.1)
*
2.7 (0.1)
*
2.7 (0.1)
*
Placebo (n = 42) 3.1 (0.2) 4.7 (0.1)
3.7 (0.1) 3.7 (0.1)
T12 (regression)
Active (n = 43)
2.1 (0.2)
*
4.0 (0.1)
*
2.3 (0.1)
*
2.5 (0.1)
*
Placebo (n = 42) 3.1 (0.2)
4.6 (0.1) 3.5 (0.1) 3.5 (0.1)
These results are expressed as arithmetic means and Standard Error Mean
(SEM). Values in bold indicate significant improvement compared to T0
(baseline); p < 0.05.
*
Difference between active and placebo is significant (p
< 0.05).
tion of a high concentration of retinol (0.4%) on the up-
per inner arm of old volunteers reduces the signs of
(a)
(b)
A Placebo-Controlled Study Demonstrates the Long-Lasting Anti-Aging Benefits of a Cream Containing Retinol,
DihydroxyMethylChromone (DMC) and Hyaluronic Acid
57
(c)
(d)
(e)
These results are expressed as arithmetic means. A star (
*
) indicates a significant difference com-
pared to both T0 (baseline) and placebo; p < 0.05.
Figure 2. In vivo clinical grading by the investigator of the wrinkles and fine lines on 10-points scales (from 0 = none to 9 =
severe). (a) Evolution of the score for forehead wrinkles; (b) Evolution of the score for crow’s feet wrinkles; (c) Evolution of
the score for crow’s feet fine lines; (d) Evolution of the score for under eye wrinkles; (e) Evolution of the score for cheek
wrinkles.
provement of wrinkle could be mediated by its capacity
to trigger pro-collagen synthesis in dermal fibroblast and
thus compensate the lower effect of low concentration of
retinol in our product. In the clinical study, we demon-
strated the potential combining retinol and DMC, in as-
sociation with low molecular weight hyaluronic acid, to
deliver in 8 weeks significant improvement on different
aging signs such as wrinkles, brown spots, radiance and
overall photoaging in 8 weeks of application.
Hyaluronic acid is described usually as a long polymer
of several hundred thousand of kilodaltons (kd) that
plays a role as a natural skin moisturizer in the epidermis
Copyright © 2012 SciRes. JCDSA
A Placebo-Controlled Study Demonstrates the Long-Lasting Anti-Aging Benefits of a Cream Containing Retinol,
DihydroxyMethylChromone (DMC) and Hyaluronic Acid
58
through its capacity to bind and structure water. Several
publications demonstrate that fragments of HA could
also play a role in the epidermal physiology, by binding
to specific receptors such as CD44, expressed on kerati-
nocyte, and that topical use of HA fragments of around
50 - 400 kd could reverse epidermal atrophy in mice [35].
Also, it has been demonstrated recently that low mole-
cular weight HA fragments of 50 kd could be delivered
in reconstructed epidermis, and induced expression of
different genes implicated in the terminal differentiation
of keratinocytes, such as claudin and occludin genes [36].
Thus, low molecular weight fragments of HA, contained
in our product, could also complement the effect of reti-
nol on the keratinocytes, and complement its action to
deliver improvement of skin aging signs, such as fine
lines and radiance. The placebo significantly delivered
benefits on skin tone and radiance, and, by consequence,
on overall photodamage. This effect is the consequence
of a moisturizing effect. Most of the parameters were
more improved after 8 weeks compared to 4 weeks of
application showing a certain degree of cumulative bene-
ficial effect over time, with active product. More impor-
tantly, the improvement of the parameters brought by
product was still significant 4 weeks after the cessation
of the treatment. This result demonstrates that pursuing
the application of a classical moisturizer, after the treat-
ment period, is sufficient for maintaining the same level
of active-induced benefits, even after a significant period
of time, such as one month.
5. Acknowledgements
This study was totally funded by Johnson & Johnson
Santé Beauté France, Issy-les-Moulineaux, France.
REFERENCES
[1] S. Akiba, R. Shinkura, K. Miyamoto, G. Hillebrand, N.
Yamaguchi and M. Ichihashi, “Influence of Chronic UV
Exposure and Lifestyle on Facial Skin Photo-Aging—
Results from a Pilot Study,Journal of Epidemiology,
Vol. 9, No. 6, 1999, pp. 136-142.
doi:10.2188/jea.9.6sup_136
[2] G. Hillebrand, “Quantitative Evaluation of Skin Condi-
tion in an Epidemiological Survey of Females Living in
Northern Versus Southern Japan,” Journal of Derma-
tological Science, Vol. 27, No. 1, 2001, pp. 42-52.
doi:10.1016/S0923-1811(01)00118-9
[3] S. Nouveau-Richard, Z. Yang, S. Mac-Mary, L. Li, P.
Bastien, I. Tardy, et al., “Skin Ageing: A Comparison
between Chinese and European Populations,” Journal of
Dermatological Science, Vol. 40, No. 3, 2005, pp. 187-
193. doi:10.1016/j.jdermsci.2005.06.006
[4] L. Petit, L. Fogouang, I. Uhoda, S. Smitz, C. Piérard-
Franchimont and G. Piérard, “Regional Variability in
Mottled Subclinical Melanoderma in the Elderly,” Ex-
perimental Gerontology, Vol. 38, No. 3, 2003, pp. 327-
331. doi:10.1016/S0531-5565(02)00200-0
[5] G. Fisher, S. Datta, Z. Wang, X. Li, T. Quan, J. Chung, et
al., “c-Jun—Dependent Inhibition of Cutaneous Procol-
lagen Transcription Following Ultraviolet Irradiation Is
Reversed by All-trans Retinoic Acid,” Journal of Clinical
Investigation, Vol. 106, No. 5, 2000, pp. 663-670.
doi:10.1172/JCI9362
[6] B. Gilchrest and M. Yaar, “Ageing and Photoageing of
the Skin: Observations at the Cellular and Molecular
Level,” The British Journal of Dermatology, Vol. 127,
No. 41, 1992, pp. 25-30.
doi:10.1111/j.1365-2133.1992.tb16984.x
[7] W. Leung and I. Harvey, “Is Skin Ageing in the Elderly
Caused by Sun Exposure or Smoking?” British Journal of
Dermatology, Vol. 147, No. 6, 2002, pp. 1187-1191.
doi:10.1046/j.1365-2133.2002.04991.x
[8] T. Quan, T. He, S. Kang, J. Voorhees and G. Fisher, “So-
lar Ultraviolet Irradiation Reduces Collagen in Photoaged
Human Skin by Blocking Transforming Growth Factor-β
Type II Receptor/Smad Signaling,” American Journal of
Pathology, Vol. 165, No. 3, 2004, pp. 741-751.
doi:10.1016/S0002-9440(10)63337-8
[9] H. Talwar, C. Griffiths, G. Fisher, T. Hamilton and J.
Voorhees, “Reduced Type I and Type III Procollagens in
Photodamaged Adult Human Skin,” Journal of Investiga-
tive Dermatology, Vol. 105, 1995, pp. 285-290.
doi:10.1111/1523-1747.ep12318471
[10] M. Brennan, H. Bhatti, K. Nerusu, N. Bhagavathula, S.
Kang, G. Fisher, et al., “Matrix Metalloproteinase-1 Is the
Major Collagenolytic Enzyme Responsible for Collagen
Damage in UV-Irradiated Human Skin,” Photochemistry
and Photobiology, Vol. 78, No. 1, 2003, pp. 43-48.
doi:10.1562/0031-8655(2003)0780043MMITMC2.0.CO2
[11] G. Fisher, S. Datta, H. Talwar, Z. Wang, J. Varani, S.
Kang, et al., “Molecular Basis of Sun-Induced Premature
Skin Ageing and Retinoid Antagonism,” Nature, Vol. 379,
1996, pp. 335-339. doi:10.1038/379335a0
[12] V. Koivukangas, M. Kallioinen, H. Autio-Harmainen and
A. Oikarinen, “UV Irradiation Induces the Expression of
Gelatinases in Human Skin in Vivo,” Acta Dermato-
Venereologica, Vol. 74, 1994, pp. 279-282.
[13] W. Montagna, S. Kirchner and K. Carlisle, “Histology of
Sun-Damaged Human Skin,” Journal of the American
Academy of Dermatology, Vol. 21, No. 5, 1989, pp. 907-
918. doi:10.1016/S0190-9622(89)70276-0
[14] J. Seo, S. Lee, C. Youn, H. Choi, G. Rhie, K. Cho, et al.,
“Ultraviolet Radiation Increases Tropoelastin mRNA Ex-
pression in the Epidermis of Human Skin in Vivo,” Jour-
nal of Investigative Dermatology, Vol. 116, 2001, pp.
915-919. doi:10.1046/j.1523-1747.2001.01358.x
[15] R. Warren, V. Gartstein, A. Kligman, W. Montagna, R.
Allendorf and G. Ridder, “Age, Sunlight, and Facial Skin:
A Histologic and Quantitative Study,” Journal of the
American Academy of Dermatology, Vol. 25, No. 5, 1991,
pp. 751-760. doi:10.1016/S0190-9622(08)80964-4
[16] L. Baumann, “Skin Ageing and Its Treatment,” Journal of
Pathology, Vol. 211, No. 2, 2007, pp. 241-251.
Copyright © 2012 SciRes. JCDSA
A Placebo-Controlled Study Demonstrates the Long-Lasting Anti-Aging Benefits of a Cream Containing Retinol,
DihydroxyMethylChromone (DMC) and Hyaluronic Acid
Copyright © 2012 SciRes. JCDSA
59
doi:10.1002/path.2098
[17] J. Leyden, “Clinical Features of Ageing Skin,” British
Journal of Dermatology, Vol. 122, No. 35, 1990, pp. 1-3.
doi:10.1111/j.1365-2133.1990.tb16118.x
[18] J. Vitto, “Connective Tissue Biochemistry of the Aging
Dermis: Age-Related Alterations in Collagen and Elas-
tic,” Dermatologic Clinics, Vol. 4, No. 3, 1986, pp. 433-
446.
[19] S. Cho, L. Lowe, T. Hamilton, G. Fisher, J. Voorhees and
S. Kang, “Long-Term Treatment of Photoaged Human
Skin with Topical Retinoic Acid Improves Epidermal
Cell Atypia and Thickens the Collagen Band in Papillary
Dermis,” Journal of the American Academy of Derma-
tology, Vol. 53, No. 5, 2005, pp. 769-774.
doi:10.1016/j.jaad.2005.06.052
[20] C. Griffiths, A. Russman, G. Majmudar, R. Singer, T.
Hamilton and J. Voorhees, “Restoration of Collagen For-
mation in Photodamaged Human Skin by Tretinoin
(Retinoic Acid),” New England Journal of Medicine, Vol.
329, 1993, p. 530. doi:10.1056/NEJM199308193290803
[21] G. Grove, M. Grove, J. Leyden, L. Lufrano, B. Schwab,
B. Perry, et al., “Skin Replica Analysis of Photodamaged
Skin after Therapy with Tretinoin Emollient Cream,”
Journal of the American Academy of Dermatology, Vol.
25, No. 2, 1991, pp. 231-237.
doi:10.1016/0190-9622(91)70187-7
[22] H. Kim, N. Kim, S. Jung, J. Mun, J. Kim, B. Kim, et al.,
“Improvement in Skin Wrinkles from the Use of Photo-
stable Retinyl Retinoate: A Randomized Controlled Trial,”
The British Journal of Dermatology, Vol. 162, No. 3,
2009, pp. 497-502.
[23] B. Chapellier, M. Mark, N. Messaddeq, C. Calleja, X.
Warot, J. Brocard, et al., “Physiological and Retinoid-
Induced Proliferations of Epidermis Basal Keratinocytes
Are Differently Controlled,” The EMBO Journal, Vol. 21,
2002, pp. 3402-3413. doi:10.1093/emboj/cdf331
[24] S. Kang, E. Duell, G. Fisher, S. Datta, Z. Wang, A.
Reddy, et al., “Application of Retinol to Human Skin in
Vivo Induces Epidermal Hyperplasia and Cellular Reti-
noid Binding Proteins Characteristic of Retinoic Acid but
without Measurable Retinoic Acid Levels or Irritation,”
Journal of Investigative Dermatology, Vol. 105, 1995, pp.
549-556. doi:10.1111/1523-1747.ep12323445
[25] L. Rittié, J. Varani, S. Kang, J. Voorhees and G. Fisher,
“Retinoid-Induced Epidermal Hyperplasia Is Mediated by
Epidermal Growth Factor Receptor Activation via Spe-
cific Induction of Its Ligands Heparin-Binding EGF and
Amphiregulin in Human Skin in Vivo,” Journal of Inves-
tigative Dermatology, Vol. 126, 2006, pp. 732-739.
doi:10.1038/sj.jid.5700202
[26] J. Varani, R. Warner, M. Gharaee-Kermani, S. Phan, S.
Kang, J. Chung, et al., “Vitamin A Antagonizes De-
creased Cell Growth and Elevated Collagen-Degrading
Matrix Metalloproteinases and Stimulates Collagen Ac-
cumulation in Naturally Aged Human Skin,” Journal of
Investigative Dermatology, Vol. 114, 2000, pp. 480-486.
doi:10.1046/j.1523-1747.2000.00902.x
[27] I. Effendy, S. Weltfriend, S. Patil and H. Maibach, “Dif-
ferential Irritant Skin Responses to Topical Retinoic Acid
and Sodium Lauryl Sulphate: Alone and in Crossover
Design,” British Journal of Dermatology, Vol. 134, No. 3,
1996, pp. 424-430. doi:10.1046/j.1365-2133.1996.26761.x
[28] V. Goffin, F. Henry, C. Piérard-Franchimont and G.
Piérard, “Topical Retinol and the Stratum Corneum Re-
sponse to an Environmental Threat,” Skin Pharmacology,
Vol. 10, No. 2, 1997, pp. 85-89. doi:10.1159/000211473
[29] B. Kim, Y. Lee and K. Kang, “The Mechanism of Reti-
nol-Induced Irritation and Its Application to Anti-Irritant
Development,” Toxicology Letters, Vol. 146, No. 1, 2003,
pp. 65-73. doi:10.1016/j.toxlet.2003.09.001
[30] E. Calikoglu, O. Sorg, C. Tran, D. Grand, P. Carraux, J.
Saurat, et al., “UVA and UVB Decrease the Expression
of CD44 and Hyaluronate in Mouse Epidermis, Which Is
Counteracted by Topical Retinoids,” Photochemistry and
Photobiology, Vol. 82, No. 5, 2006, pp. 1342-1347.
doi:10.1562/2006-02-10-RA-801
[31] G. Kaya, D. Grand, R. Hotz, E. Augsburger, P. Carraux,
L. Didierjean, et al., “Upregulation of CD44 and Hyalu-
ronate Synthases by Topical Retinoids in Mouse Skin,”
Journal of Investigative Dermatology, Vol. 124, 2005, pp.
284-287. doi:10.1111/j.0022-202X.2004.23579.x
[32] R. Kafi, H. Kwak, W. Schumacher, S. Cho, V. Hanft, T.
Hamilton, et al., “Improvement of Naturally Aged Skin
With Vitamin A (Retinol),” Archives of Dermatology,
Vol. 143, 2007, p. 606. doi:10.1001/archderm.143.5.606
[33] G. Bellemere, G. N. Stamatas, V. Bruere, C. Bertin, N.
Issachar and T. Oddos, “Antiaging Action of Retinol:
from Molecular to Clinical,” Skin Pharmacology and
Physiology, Vol. 22, No. 4, 2009, pp. 200-209.
doi:10.1159/000231525
[34] S. Tucker-Samaras, T. Zedayko, C. Cole, D. Miller, W.
Wallo and J. Leyden, “A Stabilized 0.1% Retinol Facial
Moisturizer Improves the Appearance of Photodamaged
Skin in an Eight-Week, Double-Blind, Vehicle-Con-
trolled Study,” Journal of Drugs in Dermatology, Vol. 8,
2009, p. 932.
[35] G. Kaya, C. Tran, O. Sorg, R. Hotz, D. Grand, P. Carraux,
et al., “Hyaluronate Fragments Reverse Skin Atrophy by
a CD44-Dependent Mechanism,” PLoS Medicine, Vol. 3,
2006, p. 493. doi:10.1371/journal.pmed.0030493
[36] M. Farwick, G. Gauglitz, T. Pavicic, T. Köhler, M. Weg-
mann, K. Schwach-Abdellaoui, et al., “Fifty-kDa Hyalu-
ronic Acid Upregulates Some Epidermal Genes without
Changing TNF-α Expression in Reconstituted Epider-
mis,” Skin Pharmacology and Physiology, Vol. 24, No. 4,
2011, pp. 210-221. doi:10.1159/000324296
... Although less effective, retinol has the benefit of low irritation potential when used daily. 31 Retinol is inherently an unstable molecule, making it difficult to retain activity in product formulations. Other less biologically active but more chemically stable forms of vitamin A, such as retinyl-palmitate, are commonly used skincare ingredients, often at low concentrations for the sake of marketing claims. ...
Article
Full-text available
Background Although cosmetic procedures have a significant impact on certain aspects of aging, such as deep, wrinkling, sagging, and volume loss, they fail to address the overall quality of the skin. Methods Daily skincare routines potentially can have a significant long-term impact on the overall quality of a person’s complexion. Results By expanding our product knowledge, we can help our patients individualize their at-home skincare routine using effective products and ingredients designed to address their specific skin concern and support the professional care we deliver. Conclusions Here, we discuss the types of products and ingredients suitable for the most common dermatologic concerns, from wrinkling to skin sensitivity, acne to sun damage.
... Currently, most of these products contain 0.1% or lower of retinol. However, even at this low concentration, some irritation can occur [53]. It seems that bakuchiol has acceptable skin tolerability. ...
Article
Full-text available
The study was undertaken to compare the skin care related activities of retinol and bakuchiol, a potential alternative to retinoids. Retinol is a pivotal regulator of differentiation and growth of developing as well as adult skin. Retinoic acid is the major physiologically active metabolite of retinol regulating gene expression through retinoic acid receptor - dependant and independent pathways. Comparative gene expression profiling of both substances in the EpiDerm FT full thickness skin substitute model was undertaken. Type I, III and IV collagen and aquaporin 3 synthesis in normal human dermal fibroblasts and in were analysed by ELISA and/or histochemistry in EpiDerm FT full thickness skin model were determined. Bakuchiol is a meroterpene phenol abundant in seeds and leaves of the plant Psoralea corylifolia. We present evidence that bakuchiol, having no structural resemblance to retinoids, can function as a functional analogue of retinol. Volcano plots show the great similarity of retinol and bakuchiol gene expression. Retinol-like functionality was further confirmed for the upregulation of types I, and IV collagen in DNA microarray study and also show stimulation of type III collagen in the mature fibroblast model. Bakuchiol was also formulated into a finished skin care product and was tested in clinical case study by twice-a-day facial application. The results showed that, after twelve weeks treatment, significant improvement in lines and wrinkles, pigmentation, elasticity, firmness and overall reduction in photo-damage was observed, without usual retinol therapy-associated undesirable effects. Based on these data, we propose that bakuchiol can function as an anti-aging compound through retinol-like regulation of gene expression. This article is protected by copyright. All rights reserved.
Article
Full-text available
Due to its strong water binding potential, hyaluronic acid (HA) is a well-known active ingredient for cosmetic applications. However, based on its varying molecular size, skin penetration of HA may be limited. Recent studies have demonstrated that low-molecular-weight HA (LMW HA) may show a certain proinflammatory activity. We thus aimed to characterize an LMW-sized HA molecule that combines strong anti-aging abilities with efficient skin penetration but lacks potential proinflammatory effects. Total RNA and total protein were isolated from reconstituted human epidermis following incubation with HAs of various molecular weights (20, 50, 130, 300, 800 and 1,500 kDa). Tumor necrosis factor-α expression was determined using quantitative PCR. Genomic and proteomic expression of various junctional proteins was determined using Affymetrix and common Western blotting techniques. LMWHA of approximately 50 kDa did not significantly alter tumor necrosis factor-α expression compared to 20-kDa HA, but revealed significantly higher skin penetration rates than larger sized HA associated with increased expression of genes and proteins known to be involved in tight junction formation and keratinocyte cohesion. LMW HA of approximately 50 kDa shows better penetration abilities than larger-sized HA. In addition, LMW HA influences the expression of various genes including those contributing to keratinocyte differentiation and formation of intercellular tight junction complexes without showing proinflammatory activity. These observations contribute to current knowledge on the effects of LMW HA on keratinocyte biology and cutaneous physiology.
Article
Damage to human skin due to ultraviolet light from the sun (photoaging) and damage occurring as a consequence of the passage of time (chronologic or natural aging) are considered to be distinct entities. Photoaging is caused in part by damage to skin connective tissue by increased elaboration of collagen-degrading matrix metalloproteinases, and by reduced collagen synthesis. As matrix metalloproteinase levels are known to rise in fibroblasts as a function of age, and as oxidant stress is believed to underlie changes associated with both photoaging and natural aging, we determined whether natural skin aging, like photoaging, gives rise to increased matrix metalloproteinases and reduced collagen synthesis. In addition, we determined whether topical vitamin A (retinol) could stimulate new collagen deposition in sun-protected aged skin, as it does in photoaged skin. Sun-protected skin samples were obtained from 72 individuals in four age groups: 18-29 y, 30-59 y, 60-79 y, and 80+ y. Histologic and cellular markers of connective tissue abnormalities were significantly elevated in the 60-79 y and 80+ y groups, compared with the two younger age groups. Increased matrix metalloproteinase levels and decreased collagen synthesis/expression were associated with this connective tissue damage. In a separate group of 53 individuals (80+ y of age), topical application of 1% vitamin A for 7 d increased fibroblast growth and collagen synthesis, and concomitantly reduced the levels of matrix-degrading matrix metalloproteinases. Our findings indicate that naturally aged, sun-protected skin and photoaged skin share important molecular features including connective tissue damage, elevated matrix metalloproteinase levels, and reduced collagen production. In addition, vitamin A treatment reduces matrix metalloproteinase expression and stimulates collagen synthesis in naturally aged, sun-protected skin, as it does in photoaged skin.
Article
Retinoids are widely used in the treatment of photoaging to stimulate dermal repair. However, retinoids also induce epidermal hyperplasia, which can lead to excessive scaling. Scaling is the major deterrent to topical retinoid therapy. Keratinocyte growth is strongly stimulated via ligand activation of EGFR. We examined regulation of EGFR ligands by retinoids and the role of EGFR in retinoid-induced hyperplasia in human skin in vivo. Topical treatment of human skin with all-trans retinoic acid (tRA) induces EGFR ligands heparin-binding (HB)-EGF and amphiregulin (AR), and reduces betacellulin mRNA levels. Laser capture microdissection-coupled real-time reverse transcription-PCR reveals that tRA increases HB-EGF mRNA throughout the epidermis, whereas AR induction is limited to basal keratinocytes. Topical tRA activates extracellular signal-regulated kinase 1/2 (Erk1/2) downstream EGFR effectors in human skin in vivo. tRA increases the soluble forms of AR and HB-EGF proteins, and induces epidermal hyperplasia, in human skin organ culture. Neutralization of HB-EGF or AR with specific antibodies strongly reduces tRA-induced epidermal hyperplasia. Finally, inhibition of EGFR activation by genistein reduces epidermal hyperplasia caused by topical retinoid treatment. These data demonstrate the central role of EGFR activation in retinoid-induced epidermal hyperplasia, and suggest that EGFR inhibitors can mitigate retinoid-induced scaling.
Article
Retinol is a cosmetic ingredient that is structurally similar to all-trans-retinoic acid, which has been shown to be effective in the treatment of photodamage. Since skin keratinocytes are reported to metabolize retinol to retinoic acid, investigators have hypothesized that retinol may also be helpful in improving skin photodamage. In this eight-week, double-blind, split-face, randomized clinical study, a stabilized 0.1% retinol-containing moisturizer was tested (36 subjects) against the vehicle (28 subjects) in women with moderate facial photodamage. Each product was applied once daily to the designated half side of the face. Subjects were evaluated at baseline and after four and eight weeks of treatment using a 0-9 scale for photoaging parameters. The results showed that, after eight weeks, the retinol moisturizer was significantly more efficacious than the vehicle in improving lines and wrinkles, pigmentation, elasticity, firmness and overall photodamage. Many of these differences were significant at week 4, with a progressive improvement to week 8. This study demonstrates that a formulation containing stabilized retinol is safe and effective to ameliorate the appearance of photoaged skin.
Article
Photoaged skin can be treated with retinoids, which are natural and synthetic vitamin A derivatives. However, these are photounstable and can cause skin irritation, which is a major limitation in their use in general cosmetics. Retinyl retinoate, which is an ester of all-trans retinoic acid (RA) and all-trans retinol, has reduced toxicity due to blocking of the carboxyl end group of RA and higher skin regeneration activity than retinol. To assess the efficacy of a photostable retinyl retinoate in treating women over 30 years old with periorbital wrinkles. We conducted two clinical studies with a total of 46 Korean women with periorbital wrinkles, who were not pregnant, nursing or undergoing any concurrent therapy. In the first clinical study, the efficacy of retinyl retinoate was compared with placebo. Twenty-four patients completed a 12-week trial of 0.06% retinyl retinoate applied twice daily to one side of the face and a placebo applied to the other side. In the second clinical study, the efficacy of retinyl retinoate was compared with retinol. Twenty-two patients completed an 8-week trial of 0.06% retinyl retinoate applied twice daily to one side of the face and 0.075% retinol applied to the other side. Efficacy was based on a global photodamage score, photographs, and image analysis using replicas and visiometer analysis (Skin-Visiometer SV 600; Courage & Khazaka, Cologne, Germany) every 4 weeks. The standard wrinkle and roughness parameters used in assessing skin by visiometer were calculated and statistically analysed. The retinyl retinoate-treated wrinkles improved compared with wrinkles treated with placebo or retinol, as assessed by both the investigators and the subjects. Also, skin replica analysis indicated significant improvements in retinyl retinoate-treated skin in both studies, especially in average roughness. Retinyl retinoate applied twice daily was significantly more effective than a placebo or retinol in treating periorbital wrinkles. Importantly, no severe side-effects were observed.
Article
The antiaging efficacy of retinol (ROL) has been explored mainly clinically in photoprotected skin sites and for high doses of ROL (0.4-1.6%). The objective of the study was to demonstrate the antiaging action of a low and tolerable dose of ROL (0.1%) ex vivo by measuring the expression of cellular retinoic-acid-binding protein II (CRABP2) and heparin-binding epidermal growth factor (HBEGF) by a histological evaluation of the epidermis and in vivo by assessing major aging signs and performing three-dimensional profilometry and digital imaging during a 9-month double-blind placebo-controlled study involving 48 volunteers. Finally, epidermal cell proliferation was evaluated using tryptophan fluorescence spectroscopy. Our results demonstrate that 0.1% ROL induced CRABP2 and HBEGF gene expression and increased keratinocyte proliferation and epidermal thickness. In human volunteers, topical application of a ROL-containing product improved all major aging signs assessed in our study (wrinkles under the eyes, fine lines and tone evenness). Moreover, tryptophan fluorescence increased in the active-agent-treated group and not in the placebo-treated group, indicating that cell proliferation was accelerated in vivo. These data demonstrate that a product containing a low dose (0.1%) of ROL promotes keratinocyte proliferation ex vivo and in vivo, induces epidermal thickening ex vivo and alleviates skin aging signs, without any significant adverse reaction.
Article
It is now well established that ageing occurs at the level of individual cells in the skin and other organ systems. Changes in cell behaviour, protein production and gene expression in response to standardized stimuli are readily observed in cultured cells derived from young vs old donors and from photoaged vs sun-protected body sites. Whether these changes are best viewed as a cause or a consequence of ageing cannot be determined at present. Nevertheless, available data now provide cellular and molecular correlates for the well-known differences in clinical responsiveness between newborn, adult and photoaged skin. From this basis, it will hopefully be possible to develop a more comprehensive understanding of cutaneous ageing processes.
Article
Quantitative methods were developed to assess the interrelation between age and sunlight on the facial skin of healthy women living in the same sunny area. The women were grouped into the following categories: young versus old and low versus high solar exposure. The features evaluated were perceived age, amount of facial wrinkling, skin color, and skin elasticity. A punch biopsy specimen of cheek skin was obtained and prepared histologically for evaluation of solar elastosis. The histologic examination was complemented by quantification of collagen and elastin by computer-assessed image analysis. Perceived age was estimated by untrained women viewing high quality photographs. As expected, those with greater sun exposure looked older and had more wrinkles, more severe elastosis, increased elastin, and decreased collagen.
Article
Computerized image analysis of silicone replicas, a reproducible, objective technique for measuring skin topography, was used in addition to clinical measures in two multicenter, double-blind, randomized, controlled studies of tretinoin emollient cream, a new formulation for treating photodamaged skin. Previously, the skin replica technique had been successfully used in a pilot study of tretinoin 0.05% cream by one investigator. In the present studies, subjects treated for 24 weeks with tretinoin emollient 0.05% cream consistently showed more improvement in skin topography than did vehicle-treated patients. A 0.01% concentration of tretinoin emollient cream also improved skin topography to a greater extent than the vehicle, while the lowest concentration tested (0.001%) showed little difference from vehicle. These results, reflecting a smoothening of the skin surface in tretinoin emollient cream-treated subjects, were consistent with clinical data showing greater improvement in fine wrinkling and roughness after tretinoin emollient cream therapy than after vehicle therapy. Findings from these multicenter studies confirm the value of the skin replica technique and help establish the efficacy of tretinoin emollient 0.05% cream for photodamaged skin.