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Evaluation of the Effects of Stressful Life on Human Skin Microbiota
Pierre-Yves Morvan* and Romuald Vallee
CODIF Technologie Naturelle, La Poultiere BP1, 35610 Roz-sur-Couesnon, France
*Corresponding author: Pierre-Yves Morvan, CODIF Technologie Naturelle, La Poultiere BP1, 35610 Roz-sur-Couesnon, France, E-mail: py.morvan@codif.com
Received date: November 28, 2017; Accepted date: December 26, 2017; Published date: January 3, 2018
Copyright: ©2017 Morvan PY, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted
use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Background: Due to its immune system, the skin constitutes the first barrier against environmental attack such
as chemical and physical agents or bacteria. The bacteria, viruses, archaea and fungi present on the superficial
layers of the skin correspond to the cutaneous microbiota. Its composition is crucial to the balance of the immune
system. It has already been shown that the composition of the microbiota affects the development of diseases such
as atopic dermatitis (since an increase in Staphylococcus aureus has been described), but also diabetes and
obesity. This microbiota imbalance (or dysbiosis) is mainly related to individual factors (age), diet, environmental
(climate) and behavioral factors (hygiene, consumption of antibiotics).
Aim: In our study, we are more interested in the effect of a stressful lifestyle on skin microbiota, and more
especially on skin bacteria.
Methods: We studied the skin microbiota from the faces of 70 healthy human subjects (aged 25 to 45 years).
Firstly, we worked with 2 groups of 20 volunteers selected according to their stress level, using a validated stress
score evaluation, known as the Perceived Stress Scale (PSS). Secondly, we tested the effect of a topical treatment
on the skin microflora of a group of 30 volunteers who displayed a high stress index (PSS>27).
Results: We identified a bacterial signature of stressed individuals in comparison to unstressed individuals in
term of richness and diversity. We also identified some species that are more prevalent in stressed individuals,
especially acidic and anaerobic bacteria, in relation to modified skin parameters (decreased skin pH, increased
redness and a higher level of blemishes). We then identified some benefits to the skin microbiota of stressed
individuals from a topical treatment, with an improvement in skin parameters (increased pH, reduced redness and
fewer blemishes).
Conclusion: This original study on healthy human skin microbiota will serve to direct future research addressing
the role of skin microbiota in healthy people, and metagenomic projects addressing the complex physiological
interactions between the skin and the microbes that populate this environment.
Keywords: Microbiota; Skin; Stress; Bacteria; Diversity; Imbalance
Introduction
What is the skin microbiota? e symbiosis between micro-
organisms and humans developed during evolution at two interfaces:
an internal interface which corresponds to our intestines and an
external interface which corresponds to our skin (human/environment
interface). e skin is the more supercial sheath of our organism. In
contact with the external environment, it protects our organism from
dehydration and solar radiation. It consists of several layers or strata.
We have on the surface of the skin, in intimate connection with the
stratum corneum
, an innate stratum of microorganisms referred to as
the microbiota or sometimes the
stratum microbium
[1]. e
microbiota is made up of all the micro-organisms living in an
environment and the microbiome consists of all the genetic material
originating from the micro-organisms that live in that environment
[2]. e microbiota constitutes an ecosystem of 1,000 billion bacteria,
with up to 1 million bacteria per square cm of human skin. We count
at least 19 dierent phylla with 4 major phylla (
Actinobacteria
,
Firmicutes
,
Proteobacteria
and
Bacteroidetes
), 3 main genera
(
Corynebacterium
,
Propionibacterium
,
Staphylococcus
) and more
than 500 dierent species. All of the micro-organisms hosted by the
skin constitute the skin microbiota.
What is the function of skin microbiota? It ensures the health and
homeostasis of the skin. Microbiota communities on the skin
contribute to host immune defence through a variety of mechanisms
[3]. Some of those mechanisms inhibit the growth of pathogens by
occupying space and producing bactericidal compounds, educating
adaptive immunity by tuning local cytokine production and
inuencing lymphocytes in the epidermis, and by enhancing innate
immunity by increasing production of anti-microbial peptides (which
decrease inammatory injury and strengthen the epidermal barrier).
How to study skin microbiota? DNA High roughput Sequencing
has opened a new eld of investigation during the past decade. Using
this technology, we are able to reveal the global picture of the bacteria
living on human skin and the specic skin microbiota ngerprint of
every human being. e global picture highlights the variety of
bacterial phyla and a specic picture highlights the diversity of
bacterial genera present. Each microbiota is unique. Researchers from
the Harvard T.H. Chan School of Public Health and colleagues
demonstrated that human microbiota has the potential to uniquely
identify individuals, much like a ngerprint [4]. In general, the
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ISSN: 2471-9315 Applied Microbiology: Open Access
Morvan and Vallee, Appli Microbiol Open Access
2018, 4:1
DOI: 10.4172/2471-9315.1000140
Research Article Open Access
Appli Microbiol Open Access, an open access journal
ISSN:2471-9315
Volume 4 • Issue 1 • 1000140
diversity of the cutaneous microbiota is considered to be an advantage
because a diversied ecosystem is more resilient than a poorly
diversied population [5].
Is the skin microbiota stable? Skin microbiota is determined from
birth and varies depending on age, environment, nutrition and body
area. Every day, under exposure to UV, pollution or even stress, the
equilibrium of the microbiota is threatened and can be disrupted,
leading to an imbalance called dysbiosis, which can cause skin
disorders or even pathological conditions [5]. Up to now, there has
been no data available as to the eects of a stressful lifestyle on the skin
microbiota and no information about the relationship between skin
microbiota and skin quality.
In a rst study, we evaluated the impact of continuous stress on the
cutaneous ora of healthy volunteers characterized as being in a state
of continuous stress, in comparison with a control group (not
characterized by a state of continuous stress). en, we studied the skin
condition and cutaneous ora of stressed women before and aer
application of a cream containing a combination of marine ingredients
(CMI). is CMI is a combination of dierent components designed to
provide a variety of nutrients to ensure the biodiversity and
homeostasis of the skin microbiota. It contains sugars and polyols,
sources of organic carbon which is the most important constituent of
bacteria. erefore they provide a source of energy for the cutaneous
ora. e preparation also contains peptides of sizes between 200 and
3,000 Daltons which correspond to a source of organic nitrogen that
provides amino acids for bacterial growth and protein synthesis. It also
contains a marine exopolysaccharide (EPS) known for its involvement
in intercellular communication and its protective properties against
environmental stress. In nature, this biolm maintains stable
environmental conditions by protecting marine bacteria against
desiccation. Finally the preparation contains minerals and trace
elements involved in many metabolic pathways. is diversity of
minerals supports the development of as many dierent species as
possible, with conventional or more specic nutritional needs. In this
paper, we will describe the main characteristics of the skin microbiota
(species and number) of the stressed group compared to the unstressed
group. We will subsequently present the eects of a CMI topical skin
treatment applied for 8 days on the skin microbiota and skin
parameters of a stressed group.
Materials and Methods
Products
Two formulations were tested per subject in the second study (one
product per cheek), one formulation containing the CMI at 1%, and
the other consisting of the same formulation without CMI (placebo
control). CMI is a combination of 4 marine ingredients containing 1. a
solution of an exopolysaccharide obtained by fermentation from a
marine planktonic microorganism; 2. an extract of the brown alga
Laminaria digitata
obtained by lixiviation, ltration and reverse
osmosis; 3. an enzymatic extract of the green microalga
Chlorella
vulgaris
; and 4. a marine spring water naturally rich in iron,
manganese, zinc and lithium. All the components of CMI are
produced by Codif Technologie Naturelle (France). e ratio between
each ingredient was previously determined by
in vitro
testing on
bacterial growth (not described in this article). e composition of the
2 formulas is shown in Table 1. Briey, phase A was heated at 80°C,
phase B was heated at 80°C under an emulsier at 600 rpm, then phase
C was added in B under an emulsier at 1,500 rpm for 15 min. Finally,
phase D was added to phases B and C under 2,500 rpm for 15 min.
Phase A was emulsied in BCD under 2,500 rpm for 5 min. Phase E
was added under 2,500 rpm for 10 min. Phase F was added under
2,500 rpm for 10 min. e cream was cooled with gentle stirring at
35°C and phase G (CMI) was added in the “formula with CMI”, and
not in “placebo formula”. Agitation was maintained for 15 min before
the obtained creams were conditioned in tubes. e products were
applied on a randomized half-face, by the volunteers, twice a day
(morning and evening) for 1 week. e subjects had to use a sucient
quantity of cream during each application, as for their day cream.
Formula with CMI Placebo Formula
A Cetearyl isononanoate Cetearyl isononanoate
A Phenoxyethanol Phenoxyethanol
B Aqua Aqua
B Propylene glycol Propylene glycol
B Chlorphenesin Chlorphenesin
C Acrylates/C10-30 alkyl acrylate crosspolymer Acrylates/C10-30 alkyl acrylate crosspolymer
D Sodium polyacrylate Sodium polyacrylate
E Polyacrylate-13, polyisobutene, polysorbate 20, sorbitan isostearate, aqua Polyacrylate-13, polyisobutene, polysorbate 20, sorbitan isostearate,
aqua
F Aqua, sodium hydroxyde Aqua, sodium hydroxyde
G Aqua, maris aqua, glycerin, laminaria digitata extract, phneoxyethanol, chlorella
vulgaris extract, saccharide isomerate, ethylhexylglycerin
‒–‒
Table 1: INCI listings of the 2 formulations investigated.
Citation: Morvan PY, Vallee R (2018) Evaluation of the Effects of Stressful Life on Human Skin Microbiota. Appli Microbiol Open Access 4: 140.
doi:10.4172/2471-9315.1000140
Page 2 of 8
Appli Microbiol Open Access, an open access journal
ISSN:2471-9315
Volume 4 • Issue 1 • 1000140
Panel
In the rst study, two groups of volunteers between the ages of 28
and 44 were assessed: a rst group of 22 stressed volunteers and a
second group of 22 unstressed volunteers. A group of 30 stressed
volunteers aged between 20 and 40 years were included in the second
study. All the volunteers were healthy females with phototype II to IV
and hormonally active. e inclusion criteria specic to the group of
"stressed women" were women with a stressful lifestyle (young
children, very busy and/or responsible work), believed to have
damaged skin and with a Perceived Stress Scale (PSS-14) score>27. e
inclusion criteria specic to the group of "unstressed women" were
women not experiencing a stressful lifestyle (not working, no or few
children or with older children), believed not to have damaged skin
and with a PSS-14 score<21. All groups were recruited using a stress
questionnaire. e Perceived Stress Scale (PSS) is a scientically
validated scale developed by Sheldon Cohen [6]. It is the most widely
used instrument for measuring perception of stress. It is a measure of
the degree to which situations in one’s life are appraised as stressful.
Fourteen questions were asked of the volunteers who responded using
a scale of 1 to 5: 0=never, 1=almost never, 2=sometimes, 3=fairly oen
and 4=very oen.
First study design
Each subject made 2 visits: a pre-inclusion visit (V0), and an
inclusion and experimental session (V1). A 48 h wash-out period was
observed between the inclusion visit (V0) and the experimental visit
(V1). During the rst visit (V0), the study coordinator collected
demographic and anthropometric data, including age, height and body
weight, information about lifestyle, eating habits, level of physical
activity and professional activity and asked the subject to ll-in the PSS
questionnaire (PSS score=32.6 ± 4.4 for the stressed group and PSS
score=14.5 ± 5.4 for the unstressed group, statistically dierent with
p<0.001). During the second visit (V1), volunteers lled in
questionnaires to evaluate the quality of their skin using a Visual
Analogue Scale (VAS). Skin pH was measured and the skin ora was
sampled as described below.
Second study design
is was a randomized, double-blind, placebo-controlled, cross-
over, mono centric pilot study. Each subject made 3 visits: a pre-
inclusion visit (V0), an inclusion and randomization visit and
experimental session (V1), and then an experimental session and end-
of-study visit (V2). A 48 h wash-out period was observed between visit
V0 and visit V1. During the screening visit (V0), the study coordinator
collected demographic and anthropometric data, including age, height
and body weight, information about lifestyle, eating habits, level of
physical activity and professional activity and asked the subject to ll-
in the PSS questionnaire (PSS score=33.8 ± 4.4, n=30). He also gave
each subject specic instructions to be followed. During the rst
experimental session (V1) and the last visit (V2), volunteers lled in
questionnaires to evaluate the skin quality and a skin evaluation was
performed by the clinician using a Visual Analogue Scale. e pH and
redness was measured and cutaneous ora samples were taken from
both cheeks, as described below.
Cutaneous sampling and study of the cutaneous ora
Before sampling, the subject was placed in a room for 5 to 10 min
under controlled conditions of humidity and temperature (humidity
40% to 60%, temperature 20°C to 22°C). e cutaneous ora were
sampled from the cheeks (4 cm2 per sample) using a calibrated method
of collection and a non-invasive method of “swabbing”. Bacterial DNA
from the biological samples was then extracted using a protocol with
double lysis (mechanical by bead-beating and chemical). e resulting
DNA solutions were then quantied by uorimetry. Metagenomic
analysis was conducted on a fragment of a sequence amplied by PCR
(V3-V4 fragment coding for the 16S ribosomal RNA) using a MiSeq
sequencing analysis system from Illumina. Finally, taxonomic
classication of resulting sequences was generated using a dedicated
bioinformatics pipeline based on the MOTHUR soware [7].
Skin pH and redness measurements
Skin pH measurement was performed on cheeks by a qualied
technician using a pH-Meter® PH905 probe. Skin redness was
evaluated by a qualied technician using a Colorimeter® CL400 probe.
All measurements were made under controlled conditions of humidity
and temperature (humidity 40% to 60%, temperature 20°C to 22°C).
Volunteer questionnaire
A questionnaire was lled in to assess the condition of the skin,
using a Visual Analogue Scale (VAS) from 0 to 100. Four parameters
were evaluated by the volunteers: redness of the skin (from “not at all
red” to “very red”), uniformity of the complexion (from “not at all
uniform” to “very uniform complexion”), health of the skin (from "not
at all healthy" to "very healthy"), beauty of the skin (from "my skin is
not at all beautiful" to "my skin is very beautiful").
Clinician questionnaire
A questionnaire was completed to assess the condition of the skin,
using a Visual Analogue Scale (VAS) from 0 to 100. Two parameters
were evaluated by the clinician: redness of the skin (from “not at all
red” to “very red”) and cutaneous blemishes (from “no blemishes” to
“many blemishes”).
Statistical analysis
For all statistical tests, the 0.05 level of signicance was used to
justify a claim of a statistically signicant eect. Statistical analyses
were performed using SAS® soware version 9.3 or higher (SAS
Institute Inc., Cary, NC, USA). Clinical endpoints (pH, redness and
uniformity of complexion), were analyzed using an analysis of variance
(ANOVA) model for repeated measurements (SAS® PROC MIXED,
statistical model n°1).
Results
Eects of a stressful lifestyle on skin microbiota (Study 1)
Phyla analysis provides the most global overview we can have of our
skin microbiota. And it appears very clearly that continuous
psychological stress imbalances skin microbiota. Figure 1 shows that
the total number of
Actinobacteria
and
Firmicutes
increases in the
stressed group compared with unstressed group, and the total number
of
Bacteroidetes
and
Proteobacteria
decreases in the stressed group
versus the unstressed group. e relative abundance of the skin
bacteria is also higher in the stressed group than the unstressed group
for
Actinobacteria
(49.41%
vs.
42.09%) and
Firmicutes
(28.99%
vs.
26.05%); it is lower for
Proteobacteria
(15.57%
vs.
24.09%) and
Citation: Morvan PY, Vallee R (2018) Evaluation of the Effects of Stressful Life on Human Skin Microbiota. Appli Microbiol Open Access 4: 140.
doi:10.4172/2471-9315.1000140
Page 3 of 8
Appli Microbiol Open Access, an open access journal
ISSN:2471-9315
Volume 4 • Issue 1 • 1000140
Bacteroidetes
(4.55%
vs.
5.40%). e other phyla decrease which
means a drop in diversity. erefore a stressful lifestyle seems to
directly impact the homeostasis of the skin microbiota.
Figure 1: Representation of the number of phylum readings
between stressed and unstressed skin.
Study of the most dierentiating genera shows that at least 30
genera approximately are signicantly impacted by stress. Figure 2
shows that the total numbers of
Corynebacterium
,
Propionibacterium
and
Staphylococcus
are increased, and unclassied genera are
decreased. e relative abundance is also higher in the stressed group
than the unstressed group for
Corynebacterium
(8.46%
vs.
6.05%), for
Propionibacterium
(36.22%
vs.
31.72%) and for
Staphylococcus
(14.09%
vs.
9.19%). e relative abundance for unclassied genera is
lower in the stressed group than the unstressed group (3.16%
vs.
8.21%). Due to these dierences, we can conclude that the microbiota
imprint of stressed volunteers is dierent to unstressed volunteers.
Figure 2: Representation of the number of genus readings between
stressed and unstressed skin.
Moreover, based on the most dierentiating genera, it appears that
stressed skins are characterized by 2 main changes: an increase of 7
bacteria able to survive in strict anaerobic conditions (without O2) and
an increase of 2 acidophilic bacteria (Figure 3). For example,
Finegoldia
, an anaerobic genus potentially pathogenic for the skin,
increased by 607% with stress (603 for stressed group
vs.
85 for
unstressed group). e 3 anaerobic bacteria
Peptoniphilus
,
Dialister
(which can lead to infections) and
Gardnerella
(which becomes
pathogenic when associated with anaerobic ora) increased by 470%,
361% and 256%, respectively. ey can aect the health of the skin by
causing development of symptoms linked to the activation of skin
defence systems, thus inducing inammation. e 2 genera producing
lactic acid,
Lactobacillus
and
Lactococcus
, increased with stress by
590% and 67%, respectively. is increase indicates acidication of the
surface of the skin. By contrast, a decrease in
Deinococcus
(
ermi
)
was observed in the stressed group versus the unstressed group (15
vs.
552). is species is known to be resistant to UV and gamma rays, and
can therefore decrease this resistance leading to inammation related
symptoms.
Figure 3: Representation of the variation in the number of genus
readings between the skin of stressed volunteers and that of
unstressed volunteers.
Stress tends to decrease skin pH compared to unstressed skin: 4.76
vs.
5.01, i.e. -5%, p=0.11 (Figure 4). e decrease in cutaneous pH in
the stressed group may be related to the presence of acidophilic
bacterial ora and a decrease in microbiota diversity. It has been
postulated that the greater diversity of microbiota in women versus
men may be related to a less acidic pH [8].
Figure 4: Eect of lifestyle on skin pH.
Citation: Morvan PY, Vallee R (2018) Evaluation of the Effects of Stressful Life on Human Skin Microbiota. Appli Microbiol Open Access 4: 140.
doi:10.4172/2471-9315.1000140
Page 4 of 8
Appli Microbiol Open Access, an open access journal
ISSN:2471-9315
Volume 4 • Issue 1 • 1000140
According to the volunteers, the appearance of skin redness is
signicantly greater in the stressed group compared to the unstressed
group: 53.7
vs.
32.7, i.e. +64%, p<0.05 (Figure 5). Moreover, skin
complexion in the stressed group tends to be less uniform than in the
unstressed group: 55.0
vs.
65.2, i.e. -16%, p=0.15 (Figure 6).
Figure 5: Eect of lifestyle on skin redness (self-evaluation).
Figure 6: Eect of lifestyle on uniformity of skin complexion (self-
evaluation).
Eect of treatment with CMI on skin microbiota (Study 2)
Within just 1 week, treatment with a cream containing CMI
decreased
Actinobacteria
and
Firmicutes
that had previously been
increased by stress and enhanced
Proteobacteria
and
Bacteroidetes
that
had been diminished by stress (Figure 7).
Aer 1 week of twice-daily application of the cream containing CMI
at 1%, the eect of stress on genera also begins to be reversed.
Treatment with the cream containing CMI decreased the 3 main
genera increased by stress, i.e.
Corynebacterium
,
Propionibacterium
and
Staphylococcus
(Figure 8). In addition, it increased unclassied
genera, which reects an increase in microbial diversity.
Figure 7: Representation of the number of phylum readings
between stressed skin and stressed skin treated with a cream
containing CMI at 1%.
Figure 8: Representation of the number of genus readings between
stressed skin and stressed skin treated with a cream containing CMI
at 1%.
Treatment with the cream containing CMI tends to reverse the
eect of stress for most genera: 15 genera were reduced among the 20
genera increased by the stress, i.e. 65% of them were diminished
(Figure 9). e few genera for which the eect of stress is not reversed
are not pathogenic, such as
Rhodobacter
, an aquatic and
photosynthetic bacterium;
Photobacteria
, a marine bacteria;
Selenomonas
and
Enhydrobacter
which have no known pathogenic
potential.
e main genera that we described as being increased by stress are
markedly reduced by treatment with the cream containing 1% CMI
(Table 2). Some genera were also decreased by the placebo cream (such
as
Finegoldia
and
Peptoniphilus
), but some genera were not aected by
the placebo (such as
Dialister
) or were even increased by the placebo
(such as
Gardnerella
and
Lactococcus
).
Citation: Morvan PY, Vallee R (2018) Evaluation of the Effects of Stressful Life on Human Skin Microbiota. Appli Microbiol Open Access 4: 140.
doi:10.4172/2471-9315.1000140
Page 5 of 8
Appli Microbiol Open Access, an open access journal
ISSN:2471-9315
Volume 4 • Issue 1 • 1000140
Genus Well known for… Effect of the cream containing CMI at
1%
Effect of the placebo cream
Genus increased by stress & potentially linked to inflammation
Finegoldia Potentially pathogenic for the skin -30% -36%
Peptoniphilus Can lead to infections -51% -47%
Dialister -23% 0%
Gardnerella Becomes pathogenic when associated
with anaerobic flora
-40% +133%
Genus increased by stress & potentially linked to acidification of skin pH
Lactobacillus Produces lactic acid -12% -4%
Lactococcus Metabolizes sugars in lactic acid -16% +45%
Genus decreased by stress & potentially linked to inflammation
Deinococcus Resistance to UV and gamma rays. +400% +100%
Table 2: Eect of treatment with cream containing CMI at 1% or placebo cream on some genera modied by stress.
In these last 2 cases, CMI is actually active on these stress-related
genera. In addition, treatment with the cream containing CMI re-
enhances stress-reduced genera (such as
Deinococcus
), and this eect
is greater than with the placebo cream.
Figure 9: Representation of the variation in the number of readings
of genus increased by stress between stressed skin and stressed skin
treated with a cream containing CMI.
Treatment with the cream containing 1% CMI signicantly
increases cutaneous pH decreased by stress (+13%, p<0.001) (Figure
10). Its eect is slightly greater than that of the placebo cream (+11%,
p<0.001).
Figure 10: Eect of the cream containing CMI on the pH of stressed
skin, in comparison with stressed skin before treatment (D0) and
stressed skin treated with placebo cream.
Treatment with the cream containing CMI tends to decrease redness
previously accentuated by stress while the placebo tended to increase it
(Figure 11). e dierence between the product and the placebo is
within signicant limits (p<0.1). erefore treatment with CMI
reduces redness versus the placebo.
Citation: Morvan PY, Vallee R (2018) Evaluation of the Effects of Stressful Life on Human Skin Microbiota. Appli Microbiol Open Access 4: 140.
doi:10.4172/2471-9315.1000140
Page 6 of 8
Appli Microbiol Open Access, an open access journal
ISSN:2471-9315
Volume 4 • Issue 1 • 1000140
Figure 11: Eect of the cream containing CMI on redness of
stressed skin, compared with stressed skin before treatment (D0)
and stressed skin treated with placebo cream (measured by
chromameter).
e clinical scoring performed by the beautician conrms that
treatment with the cream containing CMI at 1% signicantly reduces
redness (-34%, p<0.001) accentuated by stress (Figure 12). Its eect is
superior to that of the placebo cream (-23%, p<0.01).
Figure 12: Eect of the cream containing CMI on redness of
stressed skin, compared with stressed skin before treatment (D0)
and stressed skin treated with placebo cream (scoring).
Moreover, treatment with the cream containing 1% CMI tends to
reduce skin blemishes (-12%, p=0.16) while the placebo has no eect
(Figure 13). erefore treatment with CMI decreases visible redness
and skin blemishes within 1 week.
According to the volunteers, treatment with the cream containing
CMI at 1% signicantly improves the uniformity of the skin
complexion (+24%, p<0.01) while the placebo cream has no eect
(Figure 14). It also tends to improve the health of the skin (+13%,
p<0.1), and the beauty of the skin (+14%, p=0.1), while the placebo has
no eect on these 2 parameters (data not shown).
Figure 13: Eect of the cream containing CMI on stressed skin
blemishes, compared with stressed skin before treatment (D0) and
stressed skin treated with placebo cream (scoring).
Figure 14: Eect of the cream containing CMI on uniformity of
complexion of stressed skin, compared with stressed skin before
treatment (D0) and stressed skin treated with placebo cream (self-
evaluation).
Conclusion
Interpersonal variation was important and conrmed a high degree
of complexity in human skin microbiota. A busy lifestyle unbalances
the skin’s microbiota, reducing its diversity and increasing acidophilic
and anaerobic bacteria. is imbalance of the microbiota is associated
with imbalances of the skin such as a lower skin pH, increased redness
and more blemishes. Our combination of marine ingredients (CMI)
rebalances skin microora in 7 days. It provides a healthy and balanced
diet for skin microbiota, and rebalances skin microbiota disturbed by a
busy lifestyle. It reduces anaerobic and acidophilic bacteria potentially
involved in skin inammation, rebalances skin pH and improves the
Citation: Morvan PY, Vallee R (2018) Evaluation of the Effects of Stressful Life on Human Skin Microbiota. Appli Microbiol Open Access 4: 140.
doi:10.4172/2471-9315.1000140
Page 7 of 8
Appli Microbiol Open Access, an open access journal
ISSN:2471-9315
Volume 4 • Issue 1 • 1000140
uniform appearance of the complexion. Finally, CMI treats skin
disorders by reducing redness and blemishes. e treated volunteers
observed a global improvement in the health and the beauty of their
skin.
By reversing dysbiosis, CMI creates a new equilibrium previously
disturbed by stress.
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doi:10.4172/2471-9315.1000140
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Appli Microbiol Open Access, an open access journal
ISSN:2471-9315
Volume 4 • Issue 1 • 1000140