ArticlePDF Available

Abstract and Figures

AGING SIGNS CAN BE CLASSIFIED INTO FOUR MAIN CATEGORIES: wrinkles/texture, lack of firmness of cutaneous tissues (ptosis), vascular disorders, and pigmentation heterogeneities. During a lifetime, skin will change in appearance and structure not only because of chronological and intrinsic processes but also due to several external factors such as gravity, sun and ultraviolet exposure, and high levels of pollution; or lifestyle factors that have important and obvious effects on skin aging, such as diet, tobacco, illness, or stress. The effect of these external factors leads to progressive degradations of tegument that appear with different kinetics. The aim of this study was to clinically quantify the effect of sun exposure on facial aging in terms of the appearance of new specific signs or in terms of increasing the classical signs of aging. This study was carried out on 298 Caucasian women from 30 years to 78 years old. The participants were divided into two groups according to their sun exposure history: 157 women were characterized as sun-seeking, and the other 141 were classified as sun-phobic. This division was made possible by dermatologist grading of heliodermal status on the basis of several observations of classic criteria: wrinkles, sagging, pigmentation heterogeneities, vascular disorders, elastosis, and so on. This work was an opportunity to complete clinical photographic tools by adding in our portfolio new scales for signs observed in the two groups. Thus, 22 clinical parameters were investigated by a panel of twelve trained experts to characterize each woman's face regarding standardized photographic scales, and thus describe the aging process. By calculating statistical correlations between the four clinical clusters (wrinkles/texture, ptosis, vascular disorders, and pigmentation disorders), and real age and apparent age on the one hand and heliodermal status on the other hand, we identified a link between each clinical cluster and aging and the photoaging process. By comparing evaluations of clinical signs between the two groups for each 10-year cluster, we demonstrated that whatever the age, a prevalence of pigmentation disorders for the sun-seeking group (ie, pigmentation) is strongly linked to ultraviolet (UV) exposure. Meanwhile, clinical signs of ptosis are linked more to chronological aging and do not present differences between the two groups, nor, therefore, photoaging. Wrinkles and texture are affected by the two aging processes. Finally, clinical signs of vascular disorders present no evolution with age. Clinical signs of aging are essentially influenced by extrinsic factors, especially sun exposure. Indeed UV exposure seems to be responsible for 80% of visible facial aging signs.
Content may be subject to copyright.
© 2013 Flament et al, publisher and licensee Dove Medical Press Ltd. This is an Open Access article
which permits unrestricted noncommercial use, provided the original work is properly cited.
Clinical, Cosmetic and Investigational Dermatology 2013:6 221–232
Clinical, Cosmetic and Investigational Dermatology
Effect of the sun on visible clinical signs of aging
in Caucasian skin
Frederic Flament1
Roland Bazin2
Sabine Laquieze3
Virginie Rubert1
Elisa Simonpietri4
Bertrand Piot1
1Department of Applied Research and
Development, L’Oreal Research and
Innovation, Paris, France; 2RB Consult,
Bievres, France; 3Private Dermatology
Consultancy Practice, Montpellier,
France; 4BIOTHERM International,
Levallois-Perret, France
Correspondence: Frederic Flament
Department of Applied Research and
Development, L’Oreal Research and
Innovation, 188, Rue Paul Hochart,
94550 Chevilly-Larue, Paris, France
Email fament@rd.loreal.com
Objectives: Aging signs can be classified into four main categories: wrinkles/texture, lack of
firmness of cutaneous tissues (ptosis), vascular disorders, and pigmentation heterogeneities.
During a lifetime, skin will change in appearance and structure not only because of chronological
and intrinsic processes but also due to several external factors such as gravity, sun and ultraviolet
exposure, and high levels of pollution; or lifestyle factors that have important and obvious effects
on skin aging, such as diet, tobacco, illness, or stress. The effect of these external factors leads to
progressive degradations of tegument that appear with different kinetics. The aim of this study
was to clinically quantify the effect of sun exposure on facial aging in terms of the appearance
of new specific signs or in terms of increasing the classical signs of aging.
Materials and methods: This study was carried out on 298 Caucasian women from 30 years
to 78 years old. The participants were divided into two groups according to their sun exposure
history: 157 women were characterized as sun-seeking, and the other 141 were classified as
sun-phobic. This division was made possible by dermatologist grading of heliodermal status
on the basis of several observations of classic criteria: wrinkles, sagging, pigmentation hetero-
geneities, vascular disorders, elastosis, and so on. This work was an opportunity to complete
clinical photographic tools by adding in our portfolio new scales for signs observed in the two
groups. Thus, 22 clinical parameters were investigated by a panel of twelve trained experts to
characterize each woman’s face regarding standardized photographic scales, and thus describe
the aging process.
Results: By calculating statistical correlations between the four clinical clusters (wrinkles/
texture, ptosis, vascular disorders, and pigmentation disorders), and real age and apparent age
on the one hand and heliodermal status on the other hand, we identified a link between each
clinical cluster and aging and the photoaging process. By comparing evaluations of clinical
signs between the two groups for each 10-year cluster, we demonstrated that whatever the age,
a prevalence of pigmentation disorders for the sun-seeking group (ie, pigmentation) is strongly
linked to ultraviolet (UV) exposure. Meanwhile, clinical signs of ptosis are linked more to
chronological aging and do not present differences between the two groups, nor, therefore,
photoaging. Wrinkles and texture are affected by the two aging processes. Finally, clinical signs
of vascular disorders present no evolution with age.
Conclusion: Clinical signs of aging are essentially influenced by extrinsic factors, especially sun
exposure. Indeed UV exposure seems to be responsible for 80% of visible facial aging signs.
Keywords: photoaging, clinical evaluation, wrinkles, ptosis, pigmentation, UV
Introduction
Distinction of faces according to sex or age, is a skill we all present with very early
in our childhood. It is mainly by learning and comparing that we develop this ability.
Dovepress
submit your manuscript | www.dovepress.com
Dovepress 221
ORIGINAL RESEARCH
open access to scientific and medical research
Open Access Full Text Article
http://dx.doi.org/10.2147/CCID.S44686
Number of times this article has been viewed
This article was published in the following Dove Press journal:
Clinical, Cosmetic and Investigational Dermatology
25 September 2013
Clinical, Cosmetic and Investigational Dermatology 2013:6
For clinical and biophysical researchers to understand what
elements are taken into account in a given country or cul-
tural environment when one human being meets another and
assigns an age, is crucial.
Obviously, many clues allow us to estimate the age of
an individual; size, posture, voice intonation, and clothes
are some of the parameters taken into account. However,
facial features are the most essential element because they
provide enough information to evaluate appearance and so
recognize who the person is in front of you. Facial features
reflect not only our sex or age, but also our identity. The
structure of bones and the movement of underlying muscles
create facial features. Finally, skin is the exterior envelope
that molds all these structures together, and thus translates
our experiences. The appearance of skin reveals many life
events: physiognomy and expressions are inherent to our
character or education; diet or illness affects facial volumes
in particular; the continuing effect of gravity pulls skin down;
our behavior regarding ultraviolet (UV) exposure degrades
skin quality; and finally, our lifestyle choices, such as smok-
ing, may be responsible for premature aging by generating
noxious free radicals. Facial aging is the result of several
concomitant processes.
The face is constantly exposed to sunlight and gravity and
presents a particularity contrary to other body sites. The face
is rich in muscles that allow us, among other things, verbal
and nonverbal communication through facial expressions,
both static and dynamic. In addition, it is the prevalent area
for visible vascular changes such as discreet erythema, vaso-
constriction (pallor), or flushing (redness and sweating). By
listing all these causes, it becomes clear that distinguishing
and discriminating their exact effects in facial aging could be
complex. Indeed, each cause will induce completely different
reactions and consequences.
The literature contains plenty of articles describing
clearly and accurately the effect of sunlight exposure on
skin structures and the different processes of recovery after
sun damage.1–7 From birth, the face is constantly exposed
to sunlight, and so year by year, the skin will accumulate
damage that gradually induces the appearance of visible
signs of aging by marking areas of the skin, or perpetuating
facial expressions. Continuous UV exposure will also lead
to other changes falling under the description of photo-
induced damages, such as loss of pigmentation and vascular
homogeneities, loss of skin elasticity, and degradation of
skin texture (elastosis, hyperkeratosis, and yellowing). The
effect of sun exposure has been well described, noticeably in
pathological dimension, and the necessity of photo-protection
has been clearly demonstrated in the past to avoid any
skin diseases like skin carcinoma. Observing and quantify-
ing healthy facial skin in its clinical aging fluctuations with
different UV exposure behavior remains less documented
and an important field for investigation.
The question that arises is: how can we understand, and
measure specifically, the clinical effect of sun exposure
(photoaging) in facial aging relative to that of chronological
aging? Several authors have estimated that this ratio could be
very important,8 up to 80% of sun impact for a large part,9,10
and some publications have discussed a ratio closer to 90%.11
Can we quantify this effect? What is its contribution to facial
aging? This study examines these questions. Arriving at an
answer is quite difficult because chronological aging and
photoaging are linked through time. In fact, the older we are,
the more our face has been exposed to the sun, whatever our
lifestyles and experiences. Thus, there is no control popula-
tion: everyone has spent time in the sun in their lifetime, so
no one can serve as an “unexposed” sample. With this study,
we attempt to quantify the clinical proportion of photoaging
and chronological aging in facial evolution.
Materials and methods
The study was conducted in Montpellier (43°N; 3°E). This
town is located in the South of France and presents a high
sun exposure level (ie, it has more than 110 days of sunshine
every year).
We enrolled 298 healthy Caucasian women, aged from
30 years to 78 years, and divided them into two groups: sun-
seeking (S-S, 157 women) and sun-phobic (S-P, 141 women).
The women presented different kinds of skin type (dry, oily,
and combination) and were well-balanced across phototypes
I to IV, according to Fitzpatrick classification.12 For the fol-
lowing assessments and results, we regrouped the volunteers
into 10-year age clusters.
Two groups were established after clinical examination
performed by an experienced dermatologist and after evalu-
ation of sun behavior history by questionnaire (Sun Behavior
Score history [SBSH]). A score between 0 and 3 is given for
each 10-year cluster for different items: residence location,
occupation, passive UV exposure, active UV exposure, and
photo-protection habits. The value from 0 (none) to 3 (very)
is given by considering the importance of UV exposure for
the considered item. SBSH is the sum of scores for all the
items and varied from 4 to 30 for volunteers in their twenties,
and from 14 to 105 for volunteers in their seventies. Linked
with age and phototype, SBSH is a key descriptor of the UV
exposure level of each panelist. Therefore, the description
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
222
Flament et al
Clinical, Cosmetic and Investigational Dermatology 2013:6
Table 1 Clinical signs used by dermatologists to establish
heliodermal status
Signs Severity Scale
Pigmentation Absence, clods, puddles, poikiloderma 0 to 3
Depigmentation Absence, drops, plates 0 to 3
Pachydermic appearance Absence, presence 0, 1
Elastosis None, mild, moderate, severe 0 to 3
Cutaneous atrophy None, mild, moderate, severe 0 to 3
Vascular disorders None, mild, moderate, severe 0 to 3
Fine lines None, mild, moderate, severe 0 to 3
Wrinkles None, mild, moderate, severe 0 to 3
Ptosis None, cheeks, eyelid, face 0 to 3
Table 2 Clinical aging signs of the face, described by atlases, and
correlations with age and heliodermal status
Type and signs Age Heliodermal status
Wrinkles*
Forehead wrinkles* 0.335 0.282
Crow’s foot wrinkles* 0.602 0.478
Glabellar wrinkles* 0.553 0.396
Underneath eye wrinkles* 0.546 0.395
Upper-lip wrinkles* 0.558 0.531
Corner of the mouth* 0.520 0.402
Ptosis
Eye bag 0.529 0.303
Lower face ptosis 0.764 0.498
Note: *Signs most affected by UV exposure.
Abbreviation: UV, ultraviolet.
to ensuring that evaluation will be scientifically correct.
We obtained these data by implementing a paired tests
approach, as discussed in the Skin Aging Atlas. Volume
3, Afro-American Type15 and other literature,16,17 which
consists of a classification by 15 volunteers on a screen in
standardized conditions of lighting, position, and calibra-
tion of each grade for a considered scale by comparing all
the possible pairs of two grades. With this step, we have
been able to establish which grades are significantly dif-
ferent than others, and thus had the opportunity to remove,
adjust, or change pictures, which ensured the absence of
discrimination.
By merging the two sets of clinical scales, we obtained
a complete mapping of facial aging covering four major
axes: wrinkles and relief texture (Table 3), lack of
firmness, pigmentary disorders (Table 4), and vascular
alterations (Table 5). The description of new relevant
signs, and examples of more severe pictures regarding
these new clinical scales for this classification, are pre-
sented in Table 3.
In addition to the dermatologist evaluation and to
characterize our panel of 298 women completely on all the
22 selected scales, we used a group of 12 experts trained
to make objective evaluations regarding each standardized
clinical scale (reproducibility and repeatability). Evalu-
ation was carried out on pictures resized and reframed
according to a standard operational procedure with edit-
ing software (Photoshop®, version 10; Adobe Systems
Incorporated, New York, NY, USA) to ensure that only the
scored facial area was displayed on the screen. Pictures are
presented to each expert in random order to eliminate any
possibility of bias. The evaluation took place in entirely
standardized conditions of lighting, position (expert is
seated 1 m from the screen), and calibration (a 24-inch,
1,920 × 1,200-pixel high-resolution screen calibrated with
of panel and labeling of S-S and S-P groups was performed
with the following thresholds: 25 for the cluster aged 30 to
39 years, 34 for the cluster aged 40 to 49 years, 43 for the
cluster aged 50 to 59 years, 51 for the cluster aged 60 to 69
years, and 60 for the cluster aged 70 to 78 years.
After observation, the dermatologist assessed helioder-
mal status by taking into account the classical clinical signs
described in Table 1. Five grades of photo-damage were
determined in this process, ranging from 0 to 4 (0, none;
1, minor; 2, moderate; 3, important; and 4, major). To add
reliability and accuracy, clinical evaluation was performed
using two sets of standardized and validated photographic
scales. First, the dermatologist used the original Skin Aging
Atlas. Volume 1, Caucasian Type13 (Table 2), and second, new
clinical scales specific for populations that have been more
affected by UV exposure were built with the study pictures.
Indeed, we took advantage of this opportunity to undergo
exactly the same process of construction and validation our
previously described clinical toolboxes presented in the Skin
Aging Atlas. Volume 2, Asian Type14 with new standardized
photographic scales to observe and quantify various clinical
signs of aging and photoaging. The list of these new signs
is presented in Tables 3–5. Figures 1 and 2 show examples
of these new photographic scales for wrinkles/texture and
pigmentation issues, which allow evaluation according to
the definitions.
To make the creation of new standardized clinical
scales possible, we have taken 3 facial pictures of each
volunteer: both a front, full-face image and a 45° image
from each side. All these pictures were observed by a panel
of five experts who defined new signs and their facial posi-
tion and picked the most representative images for each
of the considered items to obtain a linear photographic
scale from grade 0 (no visible sign manifestation) to a
maximum grade found in the population. Validation of cri-
teria relevance and linearity of the scales is a prerequisite
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
223
Sun exposure and visible signs of aging
Clinical, Cosmetic and Investigational Dermatology 2013:6
Table 3 Wrinkles/texture signs and correlations with age and heliodermal status
Signs Heliodermal status Age Wrinkles and texture
Upper-lip texture*
In addition to more or less deep vertical lines,
the upper lip has a thick aspect, is padded,
and has a pronounced microrelief forming a grid
0.541 0.579
Cheek folds*
Deep folds completely anarchic and presenting
no specic directions link to muscular
movements of face
0.515 0.573
Lower lip wrinkles*
Wrinkles more or less deep from corner
of lower lip and extending downward from
the chin
0.495 0.531
Jawline folds*
Folds begin at the ear lobe created by a thick skin,
marked by dryness and elastosis, and extending
over the jaw and neck giving a crumpled paper
appearance
0.437 0.581
Wrinkles created by lower face ptosis*
A more or less deep fold is created at the zonal
level of separation of chin and cheek
0.495 0.523
Chin texture*
In addition to dimples, the area of the chin and cheek
areas adjacent have a thick skin appearance,
are padded, and have a pronounced microrelief
forming a grid
0.564 0.623
Notes: Correlations are with age and heliodermal status. *Signs most affected by UV exposure.
Abbreviation: UV, ultraviolet.
a colorimeter). We end the process by taking the average
score of all the panelists and obtaining clinical assessment
for each chosen sign for each volunteer. This approach has
allowed us to guarantee the objectivity and relevance of the
evaluation with complete randomization and no impact of
face or any environmental issues. To ensure robustness of
this process, several pictures were presented twice during
evaluations.
Finally, we added to our investigations a quiz phase
by asking 30 naïve Caucasian panelists (between 18 to 60
years of age without any specification on marital status or
profession) their opinion regarding the full-face picture of
the study volunteers. The purpose of this step is to record
the apparent age perceived by looking at a photograph.
The question asked was: “what age do you think this
woman is?”
Statistical analysis
Analysis of variance at one factor, followed by a Tukey
comparison test, was used to investigate the link between
age and heliodermal status, as well as between photo-
type and heliodermal status. The effects of age and UV
exposure were characterized by a sum of clinical criteria
divided into four clinical clusters (wrinkles, sagging,
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
224
Flament et al
Clinical, Cosmetic and Investigational Dermatology 2013:6
Table 4 Pigmentation disorders and correlations with age and heliodermal status
Signs Heliodermal status Age Pigmentary disorders
Eye contour color contrast*
Difference of color between the area surrounding
eyes and the adjacent area weathered by the sun
0.202 0.156
Pigmentation of the malar area*
Area with pigmentation disorders present on the
protruding part of the malar area at the edge of the eye
0.302 0.155
Pigmentation of the lateral area*
Area of pigmentation disorders covering the outer
lateral region of the maxilla
0.456 0.248
Lower face diffuse dyschromia*
Area of pigmentation disorders covering the lower area
of the face under a line dened by the corners of the
mouth.
0.354 0.190
Whole-face pigmentation*
Pigmentation disorders covering the entire face.
0.350 0.157
Lower face spot density*
Density of pigmentation spots in the lower part of the face
0.450 0.217
Note: *Signs most affected by UV exposure.
Abbreviation: UV, ultraviolet.
pigmentary disorders, and vascular alterations), defined
in Tables 2–5.
To determine the influence of UV effect on clinical signs
regarding evolution essentially resulting from age, Pearson
coefficients were computed between these four clinical clus-
ters and heliodermal status, as well as between the clinical
clusters and the real age of each volunteer. Finally, the cor-
relation with apparent age was also calculated to ensure the
most relevant clinical signs were taken into account in age
perception and to be able to conclude what the influence of
photoaging is on our appearance. To avoid any bias, all the
values coming from scales presenting different ranges were
normalized to five.
A t-test for independent sample was used to compare
groups in each 10-year cluster for S-S and S-P panels regard-
ing each clinical cluster. A similar statistical approach was
used to compare the difference between apparent age and
real age.
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
225
Sun exposure and visible signs of aging
Clinical, Cosmetic and Investigational Dermatology 2013:6
Grade 5
Grade 1 Grade 4
Grade 2 Grade 3
Grade 0
Figure 1 Clinical standardized photographic scale of pigmentation of malar area.
age could be approached at 0.904. We also noticed that
heliodermal status is more correlated to apparent age
than real age. Clinical signs of photoaging seem more
important both in our appearance and in its perception
by other people.
Correlations between the four clinical clusters and real
age or apparent age on one hand, and heliodermal status
on the other, are summed up in Table 6. The classifica-
tion is presented according to its correlation with apparent
age, from the highest to the lowest. This ranking shows us
that pigmentation-related clinical parameters are the most
linked to photoaging but are not the most important related
to age. In contrast, wrinkles are strongly bound to age and
heliodermal status. Sagging manifestations seem to be more
linked to chronological aging. Finally, vascular disorders
do not present a high correlation with chronological age or
heliodermal status.
Figures 4–7 show the difference for each 10-year cluster
between the S-S and S-P groups created in terms of UV
exposure behavior. On the basis of these data (Figures 4
and 6) and previous correlations, we demonstrate our
conclusions: whatever the age, a prevalence of pigmentation
disorders occurs, with significant differences between the two
groups, and these signs are the most connected to photoag-
Table 5 Microvascular disorders and correlations with age and heliodermal status
Signs Heliodermal status Age Microvascular signs
Couperosis/rosacea
Microvascular alterations on the cheekbone area
0.257 0.086
Vascular disorders
All diffused redness and microvessels visible
on the face
0.140 0.031
Note: The signs presented here are not related to UV exposure.
Abbreviation: UV, ultraviolet.
Results
In Figure 3, we show the evolution of heliodermal status with
age. First, we can observe that the effect of UV exposure
increases with age. All age clusters are statistically different
from the younger volunteers except for the cluster of those
aged 40 years to 49 years, for which the difference is only
significant at 10%.
We have computed correlations between real age
and heliodermal status (0.499) and apparent age and
heliodermal status (0.606). At the same time, we
observed that the correlation between apparent and real
Table 6 Correlations between clinical aging signs and age and
heliodermal signs
Apparent
age
Real
age
Heliodermal
status
Wrinkles/texture 0.860* 0.740* 0.604*
Ptosis 0.803* 0.774* 0.552*
Pigmentation disorders 0.416* 0.317* 0.632*
Vascular disorders 0.054 0.000 0.181
Note: *Signicant at 0.5%.
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
226
Flament et al
Clinical, Cosmetic and Investigational Dermatology 2013:6
ing. Concerning wrinkles and skin texture quality, significant
differences between the two groups appear after age 50 years.
No statistical differences for the signs of sagging are observed
between the S-S and S-P groups (Figure 5). The amplitude
of variations for vascular signs (Figure 7) is not very high,
and an evolution with age has not been established; however,
there is a significant difference in the fifties, with a maximum
for this parameter.
0
0.5
1
1.5
2
2.5
3
3.5
P<0.065
P<0.08
NS
NS
[40] [101] [92] [20]
[45]
>70 yo
60–69 y
o
50–59 y
o
40–49 y
o
30–39 y
o
Age classes
Heliodermal status
(mean ± CI)
Figure 3 Heliodermal status grade (mean ± condence interval) in each age cluster. All bars are signicantly different from the other, with an exception being the comparison
marked on the graph. The number of people in each cluster is indicated between the brackets.
Abbreviations: yo, years, CI, condence interval; NS, non signicant.
Grade 0 Grade 5
Grade 1 Grade 4
Grade 2 Grade 3
Grade 6
Grade 7
Grade 8
Figure 2 Clinical standardized photographic scale of cheek folds.
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
227
Sun exposure and visible signs of aging
Clinical, Cosmetic and Investigational Dermatology 2013:6
0
0.5
1
1.5
2
2.5
3
30–39 40–49 50–59 60–69 >70
Age classes (years)
Mean score for
pigmentation disorders
S-P
S-S
*
*
* * *
Figure 6 Comparison of pigmentation disorders. Mean scores (± CI 95%) for each age cluster between S-S and S-P.
Note: *Statistically signicant difference.
Abbreviations: S-P, sun-phobic; S-S, sun-seeking; CI, condence interval.
0
0.5
1
1.5
2
2.5
3
3.5
4
30–39 40–49 50–59 60–69 >70
Age classes (years)
Mean score of ptosis
S-P
S-S
Figure 5 Comparison of ptosis and sagging. Mean scores (± CI 95%) for each age cluster between S-S and S-P.
Note: There is no statistically signicant difference between S-P and S-S groups.
Abbreviations: S-P, sun-phobic; S-S, sun-seeking; CI, condence interval.
Figure 4 Comparison of wrinkles and relief texture. Mean scores (± CI 95%) for each age cluster between S-S and S-P.
Note: *Statistically signicant difference.
Abbreviations: S-P, sun-phobic; S-S, sun-seeking; CI, condence interval.
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
228
Flament et al
Clinical, Cosmetic and Investigational Dermatology 2013:6
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
30–39 40–49 50–59 60–69 >70
Age classes (years)
Mean score of
microvascular disorders
S-P
S-S
*
Figure 7 Comparison of microvascular disorders. Mean scores (± CI 95%) for each age cluster between S-S and S-P.
Note: *Statistically signicant difference.
Abbreviations: S-P, sun-phobic; S-S, sun-seeking; CI, condence interval.
−8
−6
−4
−2
0
2
4
6
8
30–39 40–49 50–59 60–69 >70
Age classes (years)
Apparent age – real age (+/− SEM)
S-P
S-S
*
*
*
*
Figure 8 Difference between apparent and chronological age for the S-S and S-P groups.
Notes: *Statistically signicant difference between bars. A positive difference means that the person looks older than their age.
Abbreviations: S-P, sun-phobic; S-S, sun-seeking; SEM, standard error of the mean.
70
65
75
80
85
90
Looks older by 3 years Looks one's age Looks younger by 3 years
Sun damage percent [%]
Figure 9 Percentage of sun damage is predictive of how old a woman looks.
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
229
Sun exposure and visible signs of aging
Clinical, Cosmetic and Investigational Dermatology 2013:6
The study of the effect of UV exposure on our appearance
is summarized in Figure 8. For all the women in the S-S and
S-P groups, we analyzed on all age clusters the difference
between apparent age, as estimated by a panel of 30 people, and
real age. With the exception of the eldest cluster, we observed
significant differences between the two populations (ie, S-S
volunteers looked older than their real age). This difference
seems to decrease over time. We also observed for the elder
group (older than 70 years) that people look younger than their
real age with no significant difference in sun exposure.
Finally, to quantify the effect of sun exposure on facial
aging, we chose the following method: on the basis of the
quantification of each volunteer, by way of all the pho-
tographic scales presented earlier, a sum was done of all
signs most affected by UV exposure (the 18 parameters
marked with an asterisk in Tables 2–5), which was then
compared with the sum of all clinical signs established for
facial aging (22 parameters). We are able to determine a new
ratio, sun damage percentage (SDP), which represents the
percentage between specific photoaging signs and clinical
signs. By computing this SDP, we could assess the effect
of sun exposure on the face. On average, the parameter is
80.3% ± 4.82%.
Differences between the real and apparent ages could be
divided into three groups (Figure 9): the women who seem
visually older by more than 3 years compared with their real
age, those who look their age, and finally, women who seem
younger by more than 3 years compared with their real age. At
a threshold of 80% for the SDP, women have similar apparent
age to real age. If SDP increases (82%), then apparent age
becomes higher than real age, and this woman looks older.
Conversely, a decrease of SDP (78%) means that the woman
looks younger.
Discussion
To the best of our knowledge, at this time there are no studies
that provide an objective quantification of the effect of sun
exposure on facial aging. This article attempts to provide
some elements for the quantification and understanding of the
effect of UV sun exposure on skin. Of course, as described
earlier, separating concomitant phenomena involved in
both chronological aging and photoaging is a very complex
process.
Sun exposure is essential in occidental culture and is
important not only for mood and emotional well-being but
also at a physiological level, especially for synthesis of
vitamin D. For the fair-skinned population, the effect of sun
is more severe because of the body’s natural defenses being
less efficient than in those with darker skins. In this study,
by using a simple criterion summarizing attitudes to the
sun, it was possible to define two groups of women whose
sun behavior stories were different. A comparison between
these two groups allowed us to clearly demonstrate the
effect of UV exposure in skin aging. Pigmentation signs are
most visible and most specific of these effects. This aspect
has already been described and explained very often in the
literature.5,8,18,19
In this study, we attempted to describe in the most simple
and complete way all pigmentary heterogeneities of the
face. This description is intended to define not only a way to
characterize precisely all the facial areas covered but also the
intensity and distribution of pigmentation disorders in each
of these areas. It is the clinical observation of all the pictures
that led us to the creation of standardized photographic scales.
Quantification by a panel of trained experts is a pathway for
great objectivity because each sign is evaluated independent
of all the other signs, because we could observe only one
sign on the screen. The fact that it was not possible to be
influenced by other areas and other signs, and that the result
is the average of the twelve experts, ensured the reliability
of the observations. The use of clinical scales as defined in
this article enables us to statistically characterize and detect
even small variations, for example, when they first appear
(Figures 4–7).
Clearly, clinical signs of pigmentation are strongly
determined by UV exposure. It is a more complicated matter
to conclude and separate chronological and sun-induced
effects on wrinkles and skin texture20–23 We observe that the
clinical signs describing wrinkles and skin texture are cor-
related in a very similar way in both age and heliodermal
status. According to Griffiths,18 photoaging is essentially
characterized by “coarse and fine wrinkles,” whereas signs
of chronological aging can be described as a skin with fine
wrinkles. For Griffiths, coarse wrinkles are pathognomonic
signs of extrinsic aging, although they are not only caused by
sun damage. Wrinkle characteristics of intrinsic aging also
could present themselves as “fine lines.” This confirms the
great difficulty in differentiating this parameter for chrono-
logical and sun-exposure effects. The photographic clinical
scales used during this study (Ta bles 2 and 3) could be
considered, with grade 1 as “coarse wrinkles,” and therefore
completely included in photoaging signs.18
Signs related to sagging of the tissues are not considered
in this study as being linked to the sun. Indeed, the correlation
of this clinical cluster is more important with chronological
age than heliodermal status. Conversely, we have demon-
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
230
Flament et al
Clinical, Cosmetic and Investigational Dermatology 2013:6
strated that there are no significant differences between S-S
and S-P groups, whatever the age. The remaining positive
correlation with heliodermal status could be explained by
the fact that these criteria are assessed by the dermatologist
indoors. This assertion is confirmed by literature,7,18 which
does not mention sagging as an extrinsic factor. The sagging
we evaluate with accurate photographic scales is more linked
to Earth’s gravity.
Vascular disorders are not correlated with either age
or photo-damage status. In Figure 7, we observe that this
phenomenon is opposite that of other clinical clusters.
However, literature often quotes telangiectasias7,18,21 as
important signs of sun damage. The interpretation could be
that an increase in vascular signs resulting from subclinical
inflammation gradually decreases during intrinsic aging7,22
and leads to a depletion of cutaneous blood vessels. At the
same time, there is a thickening of the epidermis and stratum
corneum, which makes the vascular network less visible.
This could explain biphasic kinetics slightly passing through
a maximum around age of 50 years, where the difference
between S-S and S-P groups becomes significant.
Finally, we show that photoaged women look older
than women who protect themselves from the sun. This
factor is higher when you are younger. Pigmentation
and wrinkles/texture, especially wrinkles around lips,
are signs that make a person look older earlier. It is an
important observation from this study that the signs of
photoaging influence age appreciation through the eyes of
other people. An increase or decrease of 2% of the SDP
can change the apparent age by plus or minus 3 years.
Thus, the term “premature skin” could correspond very
well to description of photoaged skin, which is actually
prematurely aged skin.
Conclusion
With all the elements described in this study, we could
calculate the importance of UV and sun exposure in the
visible aging of a Caucasian woman’s face. This effect is
about 80%.
The interactions between chronological and photo-
induced aging are complex, and the quantif ication of
only the effect of sun-exposure is difficult to obtain. Our
approach of using new descriptive skin-aging atlases is
a solution to specify the extrinsic influence. Twenty-two
clinical signs are used to describe and assess facial aging,
wrinkles and skin texture, sagging of tissues, pigmentation
manifestations, and vascular disorders. This study seems to
confirm that pigmentation heterogeneity is a pure photoaging
sign, whereas sagging of tissues is essentially a result of
chronological aging. Vascular disorders could be considered
as a precursor of future photoaging. Wrinkles and skin
texture are influenced by both extrinsic and intrinsic aging,
depending on the behavior of the individual with regard to the
sun. The study confirms the accountability of sun exposure
in premature aging of the face.
Disclosure
The authors report no conflicts of interest in this work.
References
1. Lavker RM, Gerberick GF, Veres D, Irwin CJ, Kaidbey KH. Cumulative
effects from repeated exposures to suberythemal doses of UVB and
UVA in human skin. J Am Acad Dermatol. 1995;32(1):53–62.
2. Lavker RM. Cutaneous aging: chronologic versus photoaging. In:
Gilchrest BA, editor. Photodammage. Cambridge, UK: Blackwell
Science; 1995:123–135.
3. El-Domyati M, Attia S, Saleh F, et al. Intrinsic aging vs photoaging:
a comparative histopathological, immunohistochemical, and ultrastruc-
tural study of skin. Exp Dermatol. 2002;11(5):398–405.
4. Giacomoni PU, Nadaud JF, Straface E, Donelli G, Heenen M,
Malorni W. Morphological alterations and cell blebbing in
UV-irradiated human epidermis. Arch Dermatol Res. 1998;290(3):
163–166.
5. Baumann L. Skin ageing and its treatment. J Pathol. 2007;211(2):
241–251.
6. Yaar M, Gilchrest BA. Photoageing: mechanism, prevention and
therapy. Br J Dermatol. 2007;157(5):874–887.
7. Gilchrest BA. Skin aging and photoaging: an overview. J Am Acad
Dermatol. 1989;21(3 Pt 2):610–613.
8. Uitto J. Understanding premature skin aging. N Engl J Med. 1997;
337(20):1463–1465.
9. Langton AK, Sherratt MJ, Griffiths CE, Watson RE. A new wrinkle
on old skin: the role of elastic fibres in skin ageing. Int J Cosmet Sci.
2010;21:1–2.
10. Farage MA, Miller KW, Elsner P, Maibach HI. Intrinsic and extrinsic
factors in skin ageing: a review. Int J Cosmet Sci. 2008;30(2):87–95.
11. Südel KM, Venzke K, Mielke H, et al. Novel aspects of intrinsic
and extrinsic aging of human skin: beneficial effects of soy extract.
Photochem Photobiol. 2005;81(3):581–587.
12. Fitzpatrick TB. The validity and particularity of sun-reactive skin types
I through VI. Arch Dermatol. 1988;124(6):869–871.
13. Bazin R, Doublet E. Skin Aging Atlas. Volume 1. Caucasian Type.
Paris: Editions Med’Com; 2007.
14. Bazin R, Flament F. Skin Aging Atlas. Volume 2. Asian Type.
Paris: Editions Med’Com; 2010.
15. Ba zi n R, Fl am ent F, Gi ro n F. Skin Aging Atlas. Volume 3.
Afro-American Type. Paris: Editions Med’Com, 2012.
16. David HA. The Method of Paired Comparisons. 2nd ed. London: Charles
Griffin and Company, 1988.
17. Gacula MC, Singh J. Statistical Methods in Food and Consumer
Research. Orlando, FL: Academic Press; 1984:410–424.
18. Griffi ths CE. The clini cal ident if ica tio n and quantifi cation of
photodamage. Br J Dermatol. 1992;127(41):37–42.
19. Glogau RG. Aesthetic and anatomic analysis of the aging skin. Semin
Cutan Med Surg. 1996;15(3):134–138.
20. Kligman AM, Zheng P, Lavker RM. The anatomy and pathogenesis of
wrinkles. Br J Dermatol. 1985;113(1):37–42.
21. Fitzpatrick RE, Goldman MP, Satur NM, Tope WD. Pulsed carbon
dioxide laser resurfacing of photo-aged facial skin. Arch Dermatol.
1996;132(4):395–402.
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
231
Sun exposure and visible signs of aging
Clinical, Cosmetic and Investigational Dermatology
Publish your work in this journal
Submit your manuscript here: http://www.dovepress.com/clinical-cosmetic-and-investigational-dermatology-journal
Clinical, Cosmetic and Investigational Dermatology is an interna-
tional, peer-reviewed, open access, online journal that focuses on
the latest clinical and experimental research in all aspects of skin
disease and cosmetic interventions. All areas of dermatology will
be covered; contributions will be welcomed from all clinicians and
basic science researchers globally. This journal is indexed on CAS.
The manuscript management system is completely online and includes
a very quick and fair peer-review system, which is all easy to use.
Visit http://www.dovepress.com/testimonials.php to read real quotes
from published authors.
Clinical, Cosmetic and Investigational Dermatology 2013:6
23. Giacomoni PU, Rein G. Skin aging: A generalization of the micro-
inflammatory hypothesis. In Farage MA, Miller KW, Maibach HI,
editors. Textbook of Aging Skin. Berlin: Springer Verlag; 2010:
789–796.
22. Alexiades-Armenakas M. Rhytides, laxity, and photoaging treated
with a combination of radiofrequency, diode laser, and pulsed light
and assessed with a comprehensive grading scale. J Drugs Dermatol.
2006;5(8):731–738.
submit your manuscript | www.dovepress.com
Dovepress
Dovepress
Dovepress
232
Flament et al
... Furthermore, cheek skin was found to be stiffer than mammary skin for the oldest age group, with a median G′ value of 2.4 kPa compared to 1.6 kPa respectively. This could be due to the impact of photoexposition 14 and/ or to the different anatomical locations, as we know that skin mechanical properties depend strongly on body location 15,16 . ...
... Both signals were collected by the same objective used for the excitation and separate by a dichroic filter (Semrock FF409-Di03-25x36). The 2PEF signal was collected between 409 and 680 nm (Semrock FF02-409/LP-25) and the SHG signal was collected at 380 nm ± 7 nm (Semrock FF01-380/ [14][15][16][17][18][19][20][21][22][23][24][25]. Images parallel to the skin plane were acquired after optical clarification of the samples. ...
Article
Full-text available
Age-related changes in skin mechanics have a major impact on the aesthetic perception of skin. The link between skin microstructure and mechanics is crucial for therapeutic and cosmetic applications as it bridges the micro- and the macro-scale. While our perception is governed by visual and tactile changes at the macroscopic scale, it is the microscopic scale (molecular assemblies, cells) that is targeted by topical treatments including active compounds and energies. We report here a large dataset on freshly excised human skin, and in particular facial skin highly relevant for cosmetics and aesthetic procedures. Detailed layer-by-layer mechanical analysis revealed significant age-dependent decrease in stiffness and elastic recoil of full-thickness skin from two different anatomical areas. In mammary skin, we found that the onset of mechanical degradation was earlier in the superficial papillary layer than in the deeper, reticular dermis. These mechanical data are linked with microstructural alterations observed in the collagen and elastic networks using staining and advanced imaging approaches. Our data suggest that with ageing, the earliest microstructural and mechanical changes occur in the top-most layers of dermis/skin and then propagate deeper, providing an opportunity for preventive topical treatments acting at the level of papillary dermis.
... For example, adaptive traits in caves such as slower growth, lower metabolic rate and lower investment in reproduction, have been associated with increased lifespan (Flatt and Schmidt, 2009). Further, many environmental features of caves such as limited food resources (Aspiras et al., 2015), lower extrinsic mortality (lack of predators; Plath and Schlupp, 2008), hypoxia (Boggs and Gross, 2021;van der Weele and Jeffery, 2022) and lack of UV irradiation (Körner et al., 2006), are consistent with known ecological predictors of longevity (Speakman and Selman, 2011;Flament et al., 2013;Omotoso et al., 2021). These nonexclusive hypotheses can be tested using model systems that have closely related species or populations in caves and on the surface, have a reliable method for estimating their age, and can survive in the laboratory to be used for experimental perturbations. ...
Article
Full-text available
An extraordinary longevity has been observed in some cave species, and this raised the hypothesis that a longer lifespan may be considered one of the characteristic traits of these animals. However, only a few cave species have been studied thus far, and a firm conclusion remains to be drawn. Here we review the available knowledge on the longevity of subterranean species, point out the limitations of previous studies, and provide suggestions for future studies to answer important questions regarding the longevity in cave animals, its adaptive value and the related promoting factors. We also argue that studying the longevity in cave animals will contribute to the field of aging, especially to understanding the evolution of this phenomenon.
... In 2019, a Nepal study with Caucasian or Mongolian tribes demonstrated that increasing age and sun exposure were the main determinants of skin aging [3]. Sun exposure on the visible areas of the skin affects the progression of skin aging by up to 80% [4]. A study demonstrated that men had significantly higher skin aging grades than women in all age groups [5]. ...
Article
Full-text available
The world population is aging and no country is immune to the consequences. We are not aware of any country-specific skin aging risk factors data for the Mongolian people. Thus, we aimed to study the risk factors associated with skin aging in the Mongolian population. A population-based cross-sectional study of 2720 study participants 18 years of age and older was performed evaluating the severity of skin aging based on cutaneous microtopography. Questionnaire data and skin physiological measurements were obtained. The odds ratios for skin aging grades associated with risk factors were estimated using ordinal logistic regression. Study participant’s mean age was 45 years, ranging from 18 to 87. After adjustment for known risk factors, skin aging was associated with demographic risk factors such as increasing age (aOR = 1.19, 95% CI 1.18–1.20), living in an urban area (aOR = 1.31, 95% CI 1.12–1.55) and lifestyle factors including being a smoker (aOR = 1.32, 95% CI 1.09–1.61), having a higher body mass index (aOR = 1.04, 95% CI 1.02–1.06) and higher levels of sun exposure time (aOR = 1.03, 95% CI 1.00–1.06) were significantly associated with higher skin aging grades. Having dry (aOR = 1.94, 95% CI 1.45–2.59) and combination skin (aOR = 1.62, 95% CI 1.22–2.16) types were also independent risk factors associated with skin aging. Having very low skin surface moisture at the T-zone (aOR = 2.10, 95% CI 1.42–3.11) was significantly related to skin aging. Older age, urban living and toxic working conditions were independent demographic risk factors related to skin aging. Smoking, higher BMI, greater levels of sun exposure were significant lifestyle risk factors. Having a skin type other than normal was a physiologic risk factor for skin aging.
... The pathophysiological changes in extrinsically aged skin are attributed to environmental factors such as ultraviolet (UV) radiation; and lifestyle factors such as diet, health status and smoking (Krutmann et al., 2017). Chronic sun exposure is thought to be a prominent contributor to the extrinsically aged skin phenotype, and in Caucasian individuals, UV radiation contributes to approximately 80% of facial ageing (Flament et al., 2013). ...
Article
Full-text available
Human skin ageing is a complex and heterogeneous process, which is influenced by genetically determined intrinsic factors and accelerated by cumulative exposure to extrinsic stressors. In the current world ageing demographic, there is a requirement for a bioengineered ageing skin model, to further the understanding of the intricate molecular mechanisms of skin ageing, and provide a distinct and biologically relevant platform for testing actives and formulations. There have been many recent advances in the development of skin models that recapitulate aspects of the ageing phenotype in vitro. This review encompasses the features of skin ageing, the molecular mechanisms that drive the ageing phenotype, and tissue engineering strategies that have been utilised to bioengineer ageing skin in vitro.
Article
Crassocephalum rabens (Asteraceae) is a common herb used in Taiwanese folk medicine to treat inflammation-related syndromes. Pharmacological studies have revealed that galactolipids exhibit anti-oxidative, anti-inflammatory, and anti-hyaluronidase activities and improve skin wrinkles, moisture, and elasticity in healthy subjects. However, the anti-aging effects of C. rabens and its primary active compound, 1,2-di-O-linolenoyl-3-O-β-galactopyranosyl-sn-glycerol (dLGG), remain elusive. Here, we investigated whether C. rabens can improve skin conditions in healthy individuals using a double-blind approach. Forty enrolled volunteers were randomly and equally assigned to the control or treatment group and were required to take either a placebo or a C. rabens extract capsule daily for one month. Skin parameters were measured before and after the study. The results showed significant differences in skin elasticity, wrinkles, collagen content, brightness, and hydration between the baseline and week 4 in the treatment group. Particularly, compared with those in the placebo group, skin wrinkles (p < 0.05), brightness (p < 0.001), collagen content (p < 0.01), and UV spots (p < 0.05) were notably improved after treatment with the C. rabens extract. Our study successfully demonstrated the application of C. rabens in preventing skin aging. Further investigations will be conducted to study the underlying anti-aging mechanism of dLGG.
Article
Photoaging, caused by exposure to sunlight and especially UVA, has been identified as one of the culprits for age-related skin deterioration. Here, we initially demonstrated that urolithin A (UroA), a metabolite derived from intestine microflora, possessed sufficient photoprotective capacity and attenuated UVA-induced senescent phenotypes in human fibroblasts, such as growth inhibition, senescence-associated β-galactosidase activity, breakdown of extracellular matrix, synthesis of senescence-associated secretory phenotypes and cell cycle arrest. Furthermore, UroA lessened the accumulation of intracellular reactive oxygen species, which promoted the phosphorylation and afterwards nuclear translocation of NRF2, subsequently driving the activation of downstream antioxidative enzymes. In parallel, we proved that UroA restored mitochondrial function by induction of mitophagy, which was regulated by the SIRT3-FOXO3-PINK1-PARKIN network. Taken together, our results showed that UroA protected dermal fibroblast from UVA damage through NRF2/ARE activation and mitophagy process, thus supporting UroA as a potential therapeutic agent for photoaging.
Article
Skin ageing is a complex process. Both intrinsic and extrinsic factors have a role in determining the speed, progression and phenotypic outcomes of the process. Typical clinical signs of ageing, such as wrinkles, thinning and sagging of the skin, are usually first noticed in the mid‐20s to early 30s. However, real‐world studies report that younger Asian women between the ages of 18 and 24 years are perceiving emerging signs of ageing, including dull skin, uneven skin tone, dryness, transient wrinkles, and a lack of skin firmness. These observations have led to a hypothesis that a phase of preageing may exist, where clinical signs of ageing are not yet present, but an individual starts to notice subtle changes in their skin's appearance. This paper discusses the concept of preageing in Asian populations and provides recommendations for recognising and managing the preageing process in clinical practice.
Article
Objective: To evaluate the capacity of the automatic detection system to accurately grade, from smartphones' selfie pictures, the severity of fifteen facial signs in South African women and their changes related to age and sun-exposure habits. Methods: A two-steps approach was conducted based on self-taken selfie images. At first, to assess on 306 South African women (20-69 years) enrolled in Pretoria area (25.74°S, 28.22°E), age changes on fifteen facial signs measured by an artificial intelligence (AI)-based automatic grading system previously validated by experts/dermatologists. Second, as these South African panelists were recruited according to their usual behavior toward sun-exposure, that is, nonsun-phobic (NSP, N = 151) and sun-phobic (SP, N = 155) and through their regular and early use of a photo-protective product, to characterize the facial photo-damages. Results: (1) The automatic scores showed significant changes with age, by decade, of sagging and wrinkles/texture (p < 0.05) after 20 and 30 years, respectively. Pigmentation cluster scores presented no significant changes with age whereas cheek skin pores enlarged at a low extent with two plateaus at thirties and fifties. (2) After 60 years, a significantly increased severity of wrinkles/texture and sagging was observed in NSP versus SP women (p < 0.05). A trend of an increased pigmentation of the eye contour (p = 0.06) was observed after 50 years. Conclusion: This work illustrates specific impacts of aging and sun-exposures on facial signs of South African women, when compared to previous experiments conducted in Europe or East Asia. Results significantly confirm the importance of sun-avoidance coupled with photo-protective measures to avoid long-term skin damages. In inclusive epidemiological studies that aim at investigating large human panels in very different contexts, the AI-based system offers a fast, affordable and confidential approach in the detection and quantification of facial signs and their dependency with ages, environments, and lifestyles.
Chapter
This chapter provides an overview of the most important skin exposome factors impacting skin aging and discusses the role of exposome factors in specific skin conditions such as atopic dermatitis, and acne. It includes some suggestions on how to limit impact of the exposome on skin. Skin aging combines two processes: intrinsic aging, the normal genetic processes that occur with time, and extrinsic aging, or accelerated aging, from exposure to skin exposome factors. The chapter focuses on exposome factors directly implicated in skin aging: exposure to solar radiation, air pollution, and tobacco smoking. The skin is directly affected by climate change, such as fluctuating humidity and temperature, and changes in the amount and type of irradiation. Climate change is expected to increase the impact of solar rays resulting in accelerated photoaging and increased incidences of certain skin cancers. A daily cosmetic skin care routine can help correct and prevent the negative effects of exposome exposure.
Book
Clinical evaluations of cosmetic or dermatological treatments are required to conclude about their efficacy in anti-aging field. For this purpose we developed skin aging atlas which allowed us to evaluate aging signs in an objective, reproducible and discerning way. These tools aim to provide the possibility of objective assessment by clinician thanks to linear photographic grading scale but also to be versatile enough to be used on populations of various ethnic and geographical origins. We present in this book not only the process of generating the different clinical scales but although the way to use them for in vivo evaluation by dermatologist. Attention is focused on specific validation studies we performed to finalize the accuracy of skin aging atlas. Finally the different uses of the data issued from atlas studies are discussed. The main signs described in the skin aging atlas book volume 2 are devoted to wrinkles characterization, to the definition of lack of firmness for tissues and to clinical semiology of pigmentation disorders.
Article
The micro-inflammatory hypothesis of skin aging can be represented as a cyclic phenomenon as follows. A cell is damaged by endogenous or exogenous factors. The damaged cell releases proinflammatory signals (prostaglandins, leukotrienes, etc.). Inflammatory signals bind to resident mast cells and induce the release of histamine and TNF-α that diffuse to blood vessels lined by endothelial cells. Stimulated by histamine and TNF-α, endothelial cells synthesize and mobilize ICAM-1. ICAM-1 synthesis can also be stimulated by anoxia, glycated proteins, neuropeptides, hormonal imbalance, or other signals not originating from damaged cells, which all are factors of skin aging. Circulating immune cells bind to ICAM-1, roll over, release hydrogen peroxide, and perform diapedesis. In the presence of chemotactic signals from damaged cell, immune cells fray a path across the dermis by releasing singlet oxygen and matrix metalloproteinases. In the absence of chemotactic signals, immune cells damage the connective tissue surrounding the blood vessels. When the damaged cell is reached, immune cells release an oxidative burst to destroy the damaged cell, engulf the debris, and proceed to the lymphatic system. In these steps, innocent bystander cells can be damaged, thus triggering another round of release of proinflammatory signals, and the cycle is repeated.
Article
Cutaneous ageing is the result of two distinct, biological processes which may occur concurrently: (i) the passage of time, termed intrinsic ageing and (ii) environmental influences, termed extrinsic ageing. Intrinsic ageing of the skin is a slow process which causes changes in tissue structure and impairs function in the absence of additional biological, chemical and physical factors. The clinical features of intrinsically aged skin are not usually evident until old age when, although smooth and unblemished, the skin surface appears pale and is characterized by fine wrinkles with occasional exaggerated expression lines. Functionally, intrinsically aged skin is dry and less elastic than more youthful skin. In contrast, extrinsically aged skin is exemplified by deep, coarse wrinkles, mottled hyperpigmentation and a marked loss of elasticity and recoil. The two major environmental influences which induce extrinsic ageing are: (i) chronic exposure to solar ultraviolet (UV) irradiation (termed photoageing) and (ii) smoking. This review discusses the changes associated with the ageing process in the skin, with particular emphasis on the role played by the elastic fibre network in maintaining dermal function. The review concludes with a discussion of a short-term assay for independent assessment of the efficacy of anti-ageing cosmetic products using the elastic fibre component fibrillin-1 as a biomarker of extracellular matrix repair. © 2010 Society of Cosmetic Scientists and the Société Française de Cosmétologie.
Article
The distinction between intrinsic and extrinsic ageing can be made on both histological and clinical grounds. Clinical criteria associated with the diagnosis of extrinsic ageing are coarse wrinkles, actinic lentigines, elastotic conditions, purpura, telangiectasia and cutaneous neoplasms. These parameters are always superimposed on changes associated with intrinsic ageing: namely, fine wrinkles and benign growths. There is heightened interest in extrinsic ageing as a result of studies demonstrating the efficacy of topical tretinoin in improving this condition. As a consequence, systems for grading extrinsic ageing have been developed, including a photographic standard scale which removes some of the subjectivity inherent to current methodology.
Article
As the population ages, common skin disorders of the elderly demand greater attention. Moreover, the many clinical, histologic, and physiologic changes that characterize old skin are increasingly implicated in its vulnerability to environmental injury and certain diseases. Thus it behooves dermatologists to study the basic biologic process of aging in the skin and the separable process of photoaging, which itself is a major clinical problem. To date studies at the cellular level have demonstrated major functional losses, particularly in proliferative capacity between infancy and adulthood, with definite further loss between early and late adulthood and as a result of chronic sun exposure. Continued careful, quantitative assessment of aging and photoaging in human skin both in vivo and in vitro will be critical to a better understanding of these processes and particularly to their successful therapeutic modification.
Article
The anatomy of linear wrinkles ("crow's feet' and temporal frown lines), fine criss-cross wrinkles of the face and wrinkling of the general body surface of elderly persons, was studied by light and scanning electron microscopy. No histological features distinguished the various wrinkles from surrounding skin. It was concluded that the wrinkle is a configuration change, like the grooves worn into an old glove, without specific structural alterations at the histological level. As regards pathogenesis, the common setting was found to be deterioration of the elastic tissue network. The skin becomes looser, excessive, and loses the ability to snap back to its original state after being deformed.