Topical Peptide Treatments with Effective
Silke Karin Schagen
Beldio Research GmbH; Kramerstrasse 15, 87700 Memmingen, Germany; email@example.com
Academic Editor: Marie Loden
Received: 26 December 2016; Accepted: 16 May 2017; Published: 22 May 2017
In the last two decades, many new peptides have been developed, and new knowledge on
how peptides improve the skin has been uncovered. The spectrum of peptides in the ﬁeld of cosmetics
is continuously growing. This review summarizes some of the effective data on cosmeceutical
peptides that work against intrinsic and extrinsic aging. Some peptides have been proven in their
efﬁcacy through clinical skin trials. Well-known and documented peptides like copper tripeptide
are still under research to obtain more details on their effectiveness, and for the development of
new treatments. Palmitoyl pentapeptide-4 and Carnosine are other well-researched cosmeceuticals.
Additionally, there are many more peptides that are used in cosmetics. However, study results for
some are sparse, or have not been published in scientiﬁc journals. This article summarizes topical
peptides with proven efﬁcacy in controlled in vivo studies.
Keywords: barrier function; anti-aging; skin care; peptides; clinical studies
Peptides and proteins are amino acid polymers. Peptides are short amino acid chains. The name
peptide is coming from pepton [peptos: digested (Greek)]. Naturally occurring human peptides
are known for cellular communication, such as protein regulation, cell proliferation, cell migration,
inﬂammation, angiogenesis, and melanogenesis [
], which results in a broad variety of physiological
processes including defense, immunity, stress, growth, homeostasis, and reproduction [
]. The ﬁrst
peptides were described by Emil Fischer and Hofmeister in the early 19th century. The ﬁrst peptide
synthesis was published in 1901 by Fischer and Fourneauin [
]. Fischer described the ﬁrst peptide
as a glycyl-glycine and in his lectures explained more peptide structure like dipeptides, tripeptides
and polypeptides [
]. Years followed, and scientists synthesized new peptides, identiﬁed more natural
peptides, and learned more about their functions. Beside the growing knowledge about natural and
synthetic peptides, different synthetic peptides were developed. Copper glycine-histidine-lysine
(Cu-GHK) was developed in 1973 by Loren Pickard. In the late 80s, the ﬁrst copper peptide was
incorporated into skin care products. Even then, peptide development proceeded slowly until the
beginning of 2000, when palmitoyl pentapeptide-4 was established. Since then, research and industry
has developed many short, stable, and synthetic peptides that have a role in extracellular matrix
synthesis, pigmentation, innate immunity and inﬂammation. These peptides are used for collagen
stimulation, wound healing, “Botox-like” wrinkle smoothing, as well as antioxidative, antimicrobial [
and whitening effects.
Topical cosmeceutical peptides can be classiﬁed as signal peptides, carrier peptides,
neurotransmitter inhibitor peptides, and enzyme inhibitor peptides.
Cosmeceutical peptides should have certain features in order to obtain good effects. Historically,
it has always been assumed that because of the skin barrier, the molecular weight of peptides should
be less than 500 Da, otherwise the peptide would not be able to pass the barrier. The moderate log
Cosmetics 2017,4, 16; doi:10.3390/cosmetics4020016 www.mdpi.com/journal/cosmetics
Cosmetics 2017,4, 16 2 of 14
of the partition coefﬁcient for octanol/water should be between 1 and 3, the melting point should be
below 200 ◦C, water solubility should be >1 mg/mL and there should be no or few polar centers .
Newer studies have shown that larger molecules can traverse the skin barrier, especially in the
case of dry and aged skin [
]. Synthetic peptides consist of amino acids chains which can be now be
modiﬁed in various ways for different functions like increased skin penetration, and increased special
receptor binding, stability, and solubility.
Some peptides are used in cosmetic products as shown in Table 1, but little
efﬁcacy data is
]. In addition, substance mixtures are on the market and tested in cosmetic formulations,
so that in many cases the actual effect of individual peptides on the skin remains unclear. Claims of
efﬁciency by cosmeceuticals are restricted to the improvement of the skin appearance. Improving
cosmeceutical function might lead to re-classiﬁcation from cosmetic to drug category, which is often
not desirable. This often limits possibilities for development.
Research on peptides should aim to identify the peptide
s mode of action, and deﬁne it for
cosmetic and/or pharmaceutical use. The prerequisites for an effective active substance must be
carefully examined before it is used. Study designs should be developed carefully, and maximal results
should be generated. With today’s methods, receptor activation, efﬁcacy, and mechanistic information
can be identiﬁed. Interesting and meaningful
studies can be developed. The development of
active peptides has opened a new ﬁeld in cosmeceutical and pharmaceutical skin care in the last decade.
This review summarizes clinical studies with peptides which conﬁrm their efﬁcacy on human skin.
Table 1. Topically used peptides.
Type of Peptide Name of Peptides
Carnosine, Copper tripeptide, Triﬂuoroacetyl-tripeptide-2,
Tripeptide-10 citrulline, Acetyl tetrapeptide-5, Acetyl tetrapeptide-9,
Acetyl tetrapeptide-11, Tetrapeptide PKEK, Tetrapeptide-21,
Hexapeptide, Hexapeptide-11, Palmitoyl pentapeptide-4, Palmitoyl
tripeptide-3/5, Palmitoyl tetrapeptide-7, Palmitoyl hexapeptide-12,
Palmitoyl oligopeptide, Palmitoyl tripeptide-1, Pentamide-6
Carrier peptides Copper tripeptide, Manganese tripeptide-1
Peptide mimetics or
Acetyl hexapeptide-3, Pentapeptide-18, Pentapeptide-3, Tripeptide-3
Enzyme inhibitor peptides Soybean peptide, Silk ﬁbroin peptide, Black rice oligopeptides
Structural protein digestion Keratin peptide
2. Peptides that Trigger the Signaling Cascade
A number of peptides are able to trigger a signaling cascade. They are released from the
extracellular matrix, and are also called matricins or collagen stimulators. With these peptides,
the proliferation of collagen, elastin, proteoglycan, glycosaminoglycan and ﬁbronectin is increased.
As a consequence, pigmentation of photo-damaged skin and ﬁne lines and wrinkles are reduced with
the regeneration of the skin matrix cells. Skin elasticity increases, and skin appears smoother and
ﬁrmer. Synthetic peptides modeled on repair signaling sequences like the following described in this
section, have been developed to rejuvenate skin.
2.1. Carnosine and N-Acetylcarnosine
Carnosine is a dipeptide (Sequence:
-Ala-His) and a well-documented aqueous antioxidant with
wound healing activity, and it is naturally present in high concentrations in muscle and brain tissues.
Carnosine is a scavenging reactive oxygen species as well as an
unsaturated aldehyde formed
from peroxidation of cell membrane fatty acids during oxidative stress. The low molecular weight
water soluble unmodiﬁed dipeptide
-Ala-His has very little afﬁnity for skin and does not penetrate
beyond the ﬁrst layer of the stratum corneum. The lipophilic peptide palmitoyl
Cosmetics 2017,4, 16 3 of 14
diffuses into the stratum corneum, epidermal, and dermal skin layers. No systemic activity has been
In two double-blind, randomized, controlled, split-face studies of four weeks each, changes in
periorbital wrinkles in women (aged 30–70) were observed (Study 1, 42 volunteers; Study 2,
35 volunteers). Tested products containing niacinamide, the peptides pal-KT and pal-KTTKS,
and carnosine, ameliorated periorbital skin, enhancing smoothness and diminishing larger wrinkle
A double-blind irradiation study comparing a complex consisting of different active
ingredients (SPF 50, photolyase, endonuclease, 8-oxoguanine glycosylase, carnosine, arazine,
and ergothionine) in available products with DNA repair, antioxidant and growth factor ingredients,
found the formulation to be effective in reducing pyrimidine dimers, protein carbonylation,
-deoxyguanosine in human skin biopsies. The formulation also appeared
to enhance the genomic and proteomic integrity of skin cells after continual UV exposure. Hence,
this formulation could be regarded as potentially lowering the risk of UV-induced cutaneous aging,
and non-melanoma skin cancer .
During a six-month study, 20 healthy volunteers (Photo type II or III) were treated with
carnosine and N-acetylcarnosine formulations. Carnosine and N-acetylcarnosine alone in a water
solution obtained 3.6% and 7.3% reduction of erythema compared to the control. Both peptides
showed antioxidant capacity, with a higher signiﬁcance in conjunction with vehicles improving
the substances’ skin penetration capabilities. N-acetylcarnosine was mentioned as an interesting
hydrophilic antioxidant for dermatological purposes .
Triﬂuoroacetyl-tripeptide-2 (Sequence: TFA-Val-Try-Val-OH) was evaluated in two
face studies. One study examined its anti-wrinkle and anti-sagging effects along the jawline of
10 volunteers (56 days) via fringe projection proﬁlometry; and the other study targeted skin ﬁrmness,
elasticity, and viscoelasticity via cytometry on 13 healthy volunteers (28 days). According to the studies,
triﬂuoroacetyl-tripeptide-2 has progressive effects on wrinkles, ﬁrmness, elasticity and sagging .
2.3. Tripeptide-10 Citrulline
Tripeptide-10 citrulline (Sequence: Lys-
-Asp-Ile-Citrulline), a decorin-like tetrapeptide,
is used to speciﬁcally target collagen ﬁber organization. Puig et al. published results of an
assessor blinded, placebo-controlled, parallel group study with 43 healthy volunteers (aged 40–58).
Tripeptide-10 citrulline showed uniformity in ﬁbril diameter, and increased skin suppleness from
better collagen ﬁber cohesion .
2.4. Palmitoyl Tripeptide-1
Palmitoyl tripeptide-1, also called pal-GHK and palmitoyl oligopeptide (Sequence:
Pal-Gly-His-Lys), is a messenger peptide for collagen renewal. Comparable to retinoic acid with
regards to its activity, it does not trigger irritation. Collagen and glycosaminoglycan synthesis are
stimulated, the epidermis is reinforced, and wrinkles are diminished. This peptide is suggested to
act on TGF
to stimulate ﬁbrillogenesis. It is used in cosmetic anti-wrinkle skincare and make-up
products. In a study with 15 women, a cream containing palmitoyl tripeptide-1 was applied twice
daily for four weeks, leading to statistically signiﬁcant reductions in wrinkle length, depth and skin
roughness. Another study applied both vehicle and palmitoyl tripeptide-1 to the skin of 23 healthy
female volunteers for four weeks [
], documenting a small but statistically signiﬁcant increase in skin
thickness (~4%, compared to the vehicle alone) .
A combination of pal-GHK tripeptide and pal-GQPR tetrapeptide is marketed as an anti-wrinkle
compound with the trade name Matrixyl
3000. A blind, randomized clinical study with 28 volunteers
twice daily applying cream including the active compound to half their face and one of their forearms
Cosmetics 2017,4, 16 4 of 14
and a placebo cream to the other half of the face and other forearm conﬁrmed anti-wrinkle efﬁcacy,
reduction of wrinkle depth, volume and density, skin roughness and complexity, as well as a decrease
of the area occupied by deep wrinkles, and an increase in skin tone .
2.5. Palmitoyl Tripeptide-3/5
Palmitoyl tripeptide-3/5 mimics the effects of an extracellular matrix protein, thrombospondin-1
(TSP-1), a naturally occurring molecule that increases TGF
activity. In animal models and human
dermal ﬁbroblasts cell culture tests, TSP-1 acts locally to improve wound healing, and is believed to be
active in the post-natal development of skin structures [
]. The short sequence Lys-Arg-Phe-Lys of
the TSP-1 protein is responsible for TGF
in turn, causes a persistent increase in
the amounts of Type I and Type III collagen that dermal ﬁbroblasts produce. Palmitoyl tripeptide-3/5
(Sequence: Pal-Lys-Val-Lys bistriﬂuoracetae salt) (SYN
-COLL) stimulates collagen production in
in vitro and in vivo studies through the growth factor TGFβ.
Animal studies indicate that palmitoyl tripeptide-3/5 may increase collagen synthesis.
studies show that palmitoyl tripeptide-3/5 can prevent collagen breakdown by interfering with
MMP1 and MMP3 collagen degradation. Palmitoyl tripeptide-3/5 seems to boost collagen synthesis,
but decreases collagen breakdown. Additional data show that palmitoyl tripeptide-3/5 is roughly
3.5 times more effective at reducing the appearance of wrinkles than the placebo [
a palmitoyl tripeptide-3/5 (10 to 25 ppm) cream formulation demonstrated a dose-dependent wrinkle
reduction, measured by PRIMOS surface topography .
In an efﬁcacy study performed on 60 Chinese volunteers (84 days, applied twice daily),
palmitoyl tripeptide-3/5 conﬁrmed its anti-wrinkle efﬁcacy and reduced skin roughness better than
control groups, placebo and pal-KTTKS-containing creams .
2.6. Palmitoyl Tripeptide-38
Epithelial regeneration in skin is achieved by the constant turnover and differentiation of
keratinocytes. Epidermal and dermal stem cell compartments are fundamental for the continuous
renewal of the skin. Adult stem cells are the unique source for skin tissue renewal. Plants also have
stem cells and plant-derived stem cell extracts are now used in topical products for their potential
anti-aging and anti-wrinkle effects.
A dermocosmetic product containing apple stem cell extract, urea, creatine and palmitoyl
tripeptide-38 (Sequence: Pal-Lys-Met(O2)-Lys-OH) was applied on the face twice daily for 28 days,
and assessed by clinical and instrumental evaluation in 32 women with sensitive skin bearing crow’s
feet wrinkles. The treatment results showed a signiﬁcant increase in dermal density and elasticity,
as well as anti-wrinkle effects. The anti-aging serum seems to improve aging skin signs with the ﬁrst
visible results achieved after one week treatment .
To determine the effectiveness of a multi-ingredient anti-aging moisturizer, an open label
clinical trial was conducted with 37 female subjects of ages 35–60. The effective ingredients of
the moisturizer for the facial skin included Astragalus membranaceus root extract, a peptide blend
including palmitoyl tripeptide-38, standardized rosemary leaf extract (ursolic acid), tetrahexyldecyl
ascorbate, and ubiquinone. Results were favorable in both product efﬁcacy measurements and aesthetic
self-assessment questionnaires, with subjects judging the product as being mild and well-tolerated [
2.7. Palmitoyl Pentapeptide-4
Palmitoyl pentapeptide-4, (Matrixyl
) (Sequence: Pal-Lys-Thr-Thr-Lys-Ser-OH or pal-KTTKS-OH)
is a small, highly speciﬁc biologically active peptide which has been reported to stimulate the
production of elastin, ﬁbronectin, glucosaminoglycan and collagens (speciﬁcally Types I, III and
IV), support of the extracellular matrix, and wound healing. KTTKS structure is related to the
precursor of collagen Type I (or procollagen Type I). The stimulatory effect of KTTKS on collagen
Types I and III, and ﬁbronectin, seems to relate mainly to the biosynthetic pathway, rather than the
Cosmetics 2017,4, 16 5 of 14
export or degradation pathways. KTTKS has a molecular weight of 563.64 Da, the longer pal-KTTKS is
In a placebo-controlled double blind study, pal-KTTKS (0.005%) formulation was applied to the
right periocular area twice daily for 28 days [
]. As demonstrated by optical proﬁlometry, this resulted
in a quantitative decrease in fold depth, fold thickness, and skin rigidity, by 18%,
37%, and 21%
respectively. These results were conﬁrmed in two other placebo-controlled double blind studies in
women (42 and 35 subjects) with moderate to distinct periorbital wrinkles .
A double-blind, placebo-controlled, split face, left-right randomized trial involving 93 subjects
was carried out to assess the clinical efﬁcacy of pal-KTTKS, with ﬁne line or wrinkle improvement
as the parameter of interest [
]. In another four month-long double-blind study, 49 women were
directed to apply either pal-KTTKS or vehicle twice daily to their faces. The results showed that
pal-KTTKS exhibited signiﬁcant improvement in skin roughness, wrinkle volume, and wrinkle depth,
compared with the vehicle. Data associated pal-KTTKS with an increase in elastin ﬁber density and
thickness, as well as improved collagen IV regulation at the dermal-epidermal junction .
2.8. Palmitoyl Tetrapeptid-7
Palmitoyl tetrapeptide-7 (Rigin
) (Sequence: Pal-Gly-Gln-Pro-Arg or pal-GQPR) is a fragment of
immunoglobulin G. Palmitoyl tetrapeptide-7 decreases IL-6 secretion in a basal setting, and serves
as an anti-inﬂammatory after exposure to UVB-irradiation.
reﬂectance confocal microscopy
studies indicated that a blend of palmitoyl oligopeptide and palmitoyl tetrapeptide-7 enhanced
the extracellular matrix structure compared to placebo [
]. Sixty healthy photoaged volunteers
(aged 45–80) were tested over 12 months with a formulation containing palmitoyl tetrapeptide-7 and
another active ingredient. A reduction of facial wrinkles was documented by this long-term use.
Better skin appearance was related to the deposition of ﬁbrillin-rich microﬁbrils in the papillary dermis
of treated skin .
2.9. Palmitoyl Hexapeptide-12
Palmitoyl hexapeptide-12 (Sequence: Pal-Val-Gly-Val-Ala-Pro-Gly), which is the peptide in
Biopeptide-EL, creates a response in the dermis of the skin that stimulates collagen and elastin
ﬁbroblasts, developing ﬁbronectin and glycosaminoglycans. It is believed to work by reducing the
production of interleukin-6 (IL-6) by key skin cells, keratinocytes and ﬁbroblasts. IL-6 is a molecule
that promotes inﬂammation, which, in turn, leads to faster degradation of the skin matrix, and thus
contributes to the development of wrinkles, and loss of skin ﬁrmness and elasticity. By reducing the
levels of IL-6 and possibly other inﬂammation mediators, palmitoyl is thought to slow down the
degradation of the skin matrix, and may also stimulate its replenishment.
A one month double-blind study was conducted on 10 female volunteers, aged 32–56,
who performed twice daily applications of a light emulsion containing 4%, or a placebo.
Palmitoyl hexapeptide treatment improved elasticity, tone, skin fatigue and ﬁrmness .
2.10. Acetyl Tetrapeptide-9/11
Acetyl tetrapeptide-9 (Dermican
) (Sequence: N-Acetyl-Gln-Asp-Val-His) is reported to
stimulate collagen Type I and lumican synthesis, whereas acetyl tetrapeptide-11 (Sequence:
) stimulates keratinocyte cell growth and syndecan-1 synthesis.
Clinical studies documented that treatment with acetyl tetrapeptide-9 (17 female volunteers) or acetyl
tetrapeptide-11 (19 female volunteers) led to thicker and ﬁrmer skin. Both peptides were more effective
compared to placebos .
Tetrapeptide-21, also named GEKG (Sequence: Gly-Glu-Lys-Gly), was derived from ECM proteins.
Its amino acid sequence is glycine-glutamic acid-lysine-glycine. This peptide demonstrated in
Cosmetics 2017,4, 16 6 of 14
studies, an increase of collagen (Type I) production on the protein level and mRNA level,
hyaluronic acid synthase 1 production, and a strong increase in ﬁbronectin (GEKG Conc. 0.001%).
Increase in collagen (COL1A1), procollagen, hyaluronic acid and ﬁbronectin, as well as skin elasticity,
were measured in a double-blind, randomized, placebo-controlled study (10 women/eight weeks).
A placebo-controlled study with 30 subjects was carried out to analyze the effect of GEKG on facial
wrinkles. GEKG signiﬁcantly decreased skin roughness.
In a comparison study with GEKG vs. pal-KTTKS with 60 subjects, elasticity increased after two
daily treatments over eight weeks by 41.3% for GEKG, while pal-KTTKS showed an improvement of
2.12. Tetrapeptide PKEK
Tetrapeptide PKEK (Sequence: Pro-Lys-Glu-Lys) can exert skin whitening effects. For PKEK
development, Lys-Glu-Lys (KEK) was modiﬁed with proline to stabilize the peptide structure.
Study results showed that PKEK reduces interleukin-6, interleukin-8, and tumor necrosis factor-
as well as cyclooxygenase gene expression in UV light-stressed keratinocytes .
The treatment of human keratinocytes with PKEK signiﬁcantly reduced UVB-stimulated mRNA
expression of interleukin (IL)-6, IL-8 and TNF-
and, most importantly, proopiomelanocorticotropin
(POMC). In a randomized, double-blind, vehicle-controlled study with PKEK treatment once daily,
punch biopsies of 10 healthy volunteers were taken after four weeks. PKEK treatment signiﬁcantly
inhibited UVB-induced upregulation of genes encoding for IL-1
, IL-6, IL-8, TNF-
as well as POMC
and tyrosinase in skin areas pretreated with PKEK.
A second study was performed as a half-face
efﬁcacy test with 39 Caucasian women.
Facial pigment spots were signiﬁcantly faded after six weeks when PKEK was combined with the
skin whitener sodium ascorbyl phosphate. PKEK or sodium ascorbyl phosphate alone led to less
pronounced fading of the pigment spots than a combination of the two. An
efﬁcacy study conﬁrmed the above result after application for eight weeks to the back of the hands of
In the fourth study, 27 Japanese women were separated in two groups which treated faces twice
daily with either sodium ascorbyl phosphate only, or with a PKEK + sodium ascorbyl phosphate
formulation, for eight weeks. Application of PKEK + sodium ascorbyl phosphate signiﬁcantly reduced
skin pigmentation by 26%, and sodium ascorbyl phosphate by 18%, according to the SCINEXA score.
It was conﬁrmed that PKEK has the capacity to reduce UVB-induced skin pigmentation in all study
models, and it may be suitable as a skin tone-modulating agent in cosmetic products .
Hexapeptide-11 (Pentamide-6, Sequence: Phe-Val-Ala-Pro-Phe-Pro) was originally isolated from
Saccharomyces yeast fermentation, but was later synthesized because of purity issues. Hexapeptide-11
has the ability to inﬂuence the onset of senescence in intrinsically and extrinsically aged ﬁbroblasts,
and extrinsically aged dermal papillae cells
]. Gorouhi and Maibach reviewed a
placebo-controlled study with 25 healthy volunteers, treating their skin twice daily for four weeks.
Initial skin elasticity and deformation response were improved .
Hexapeptide-14 (palmitoyl hexapeptide-14) has been reported to stimulate cell migration, collagen
synthesis, and ﬁbroblast proliferation and scaffolding [
]. A 12-week study with 29 volunteers showed
results of reduced ﬁne lines and wrinkles by palmitoyl hexapeptide-14. Results were compared with
tretinoin and no irritations were noted .
Cosmetics 2017,4, 16 7 of 14
3. Carrier Peptides
Carrier peptides deliver or stabilize trace elements like copper and manganese, necessary for
wound healing and enzymatic progress. These peptides are involved in copper or manganese transport
into skin cells. Additionally, they are obtained by binding copper with a tripeptide .
3.1. Copper Tripeptide
Copper tripeptide (Cu-GHK, lamin
) complex (Sequence: Copper Gly-L-His-L-Lys) is one of
the most well-examined peptides. It plays a role in the extracellular matrix, and is released in
wounds or inﬂammation to support healing. It acts as signal and carrier peptide, promotes regular
collagen, elastin, proteoglycan, and glycosaminoglycan synthesis, and provides anti-inﬂammatory and
antioxidant responses. In cosmetic applications, Cu-GHK is used in anti-aging, anti-wrinkle, after-sun,
skin renewal, skin moisturizer, hair growth stimulating products .
Cu-GHK stimulates cellular regulatory molecules and regenerates, and heals skin and other
tissues. Stem cells treated with GHK regenerated and expressed more stem cell markers. GHK and
Gly-Gly-His (GGH) reduce TNF-
induced cytokines IL-6 [
], thus ensuring better wound healing.
Pickart et al. described that GHK signiﬁcantly increased the expression of DNA repair genes,
while 47 genes
are stimulated and ﬁve genes are suppressed [
]. GHK is involved with different
mechanisms of action and can apparently promote regeneration, healing, and repair. It furthermore
achieves good effects against the aging processes.
Cu-GHK can stimulate hair growth. The copper tripeptide complex ensures follicular enlargement
and helps covering the follicle with a downy hair; the effect is comparable with that of Minoxidil [
The results of a hair transplant showed signiﬁcant improvement [
] following application with
a copper tripeptide product. Topical Cu-GHK products stimulate collagen synthesis on the scalp,
strengthen existing hair, and encourage hair growth .
Several studies conﬁrming Cu-GHK efﬁcacy in various areas have been performed. These include:
increasing keratinocyte proliferation, improving appearance, ﬁrmness, elasticity, skin thickness,
wrinkles, spotty hyperpigmentation and light damage, skin collagen, strengthening proteins of skin
protection barrier, and improvement of skin appearance.
Experiments have shown that
Cu-GHK increases and stimulates the synthesis of collagen,
glycosaminoglycans and other extracellular matrix molecules. Several placebo-controlled clinical
trials have conﬁrmed the observed effects [
]. A topically applied cream with Cu-GHK was shown
to stimulate dermal skin procollagen synthesis. Synthesis induced by the copper tripeptide was
signiﬁcantly superior to vitamin C, tretinoin, or melatonin in comparison.
Similarly, a study of 20 women compared the skin’s production of collagen after applying creams
containing Cu-GHK, vitamin C, or retinoic acid to thighs daily for one month. New collagen production
was determined by skin biopsy samples using immunohistological techniques. After one month,
Cu-GHK increased collagen in 70% of those treated, versus 50% treated with vitamin C, and 40%
treated with retinoic acid .
Leyden et al. conﬁrmed in two different studies (12 weeks of application by 71 or 41 women) the
clinically beneﬁcial effects of Cu-GHK formulations on both aged and sun damaged skin. The Cu-GHK
face cream and an eye cream reduced the visible signs of skin aging and caused an increase in skin
density and thickness. The researchers observed improved skin elasticity and skin humidity, signiﬁcant
smoothing of the skin by stimulating the synthesis of collagen, a signiﬁcant improvement of the skin
contrast, and diminished wrinkles .
In another study Cu-GHK cream was applied twice a day for 12 weeks on 67 women. The Cu-GHK
cream improved the appearance of photo-damaged, aged skin. By histological analyses of biopsies,
it was re-conﬁrmed that the use of topically applied Cu-GHK products intensiﬁed skin thickness in
the range of the epidermis and dermis, and that keratinocyte proliferation of the skin was greatly
Cosmetics 2017,4, 16 8 of 14
3.2. Manganese Tripeptide-1
Besides the well-researched copper tripeptide, there is also one clinical study focusing on
manganese tripeptide-1 (Sequence: GHK-Mn
). This study evaluated the effects of a manganese
peptide complex in the treatment of various signs of cutaneous facial photo-damage. During a 12-week
period, subjects were instructed to apply a facial serum formulation containing the manganese peptide
complex twice a day. This resulted in their skin’s photo-damage ranking shifting from moderate to
mild. The most signiﬁcantly improved parameters were associated with hyperpigmentation, while no
signiﬁcant cutaneous inﬂammation was reported .
4. Neurotransmitter Inhibitor Peptides
Muscle contraction is another strategy to reduce common ageing signs like ﬁne lines and wrinkles.
Muscles are contracted by neurotransmitter release from neurons. The neurotransmitter begins a
cascade with protein-protein interactions that culminate in the fusion of neurotransmitter loaded
vesicles with the neuron membrane. A local modiﬁcation in the membrane potential triggers the entry
of calcium ions into the neuron via the terminal. When these ions enter the pre-synaptic terminal,
vesicles containing acetylcholine join other parts of the neuron to release acetylcholine. This process
is mediated by a SNAP receptor protein, which include the vesicle-associated membrane protein,
the membrane-associated protein syntaxin, and synaptosomal-associated protein 25. These proteins
directly manage vesicle docking and fusion though the formation of the SNARE complex. The SNARE
complex captures vesicles and fuses them with the membrane. Once the fusion of these vesicles
occurs, acetylcholine is released into the synapse between muscle and nerve. Acetylcholine binds to
acetylcholine receptors located on the surface of the muscle cells, and this leads to muscle contraction.
Topical synthetic peptides which imitate the amino acid sequence of the synaptic protein SNAP-25
were shown to be speciﬁc inhibitors of the neurosecretion. For this reason, these peptides are also
called neurotransmitter inhibitor peptides. These cosmeceutical peptides penetrate skin and relax
muscles, causing the reduction and softening of wrinkles and ﬁne lines.
) has the sequence Acetyl-Glu-Glu-Met-Gln-Arg-Arg-NH
and is reported to inhibit the release of neurotransmitters, which is followed by anti-wrinkle,
moisturizing effects. It seems to improve the ﬁrmness and tone of the skin. Acetylhexapeptide-3 is a
copy of the synaptosomal-associated protein 25, which competes for a position in the SNARE complex,
and destabilizes its formation without breaking any of its constituent parts. Additionally, it inhibits
catecholamine secretion [
]. An increase in peptide concentration and the permeation of peptides,
and a decrease in iontophoretic permeability coefﬁcients, are affected by a number of parameters that
can be optimized for effective transdermal peptide delivery .
Blanes-Mira described a placebo-controlled study in which acetylhexapeptide-3 (10%) vs. placebo
creams were applied twice daily (10 women, 30 days). Acetylhexapeptide-3-treated skin areas showed a
30% improvement in wrinkles in the eye area [
]. The anti-wrinkle efﬁcacy in the acetylhexapeptide-3
group was measured as 48.9%, compared with 0% in the placebo group. All parameters of roughness
were decreased in the same study. The fold depth in the acetylhexapeptide-3 group (48.9%) was
signiﬁcantly reduced (60 subjects) .
) (Sequence: Gly-Pro-Arg-Pro-Ala) is derived from snake venom. It is an
antagonist of the acetylcholine receptor, and blocks nerves at the post-synaptic membrane, leading to
muscle relaxation. Clinical studies demonstrated a reduction of wrinkles by 49%, and lesser skin
roughness (47%) after a treatment of 28 days .
Cosmetics 2017,4, 16 9 of 14
) (Sequence: Tyr-D-Ala-Gly-Phe-Leu) mimics the natural mechanism
of enkephalins, and inhibits neuronal activity and catecholamine release. Its action can be described as
having botox-like effects; and it demonstrates a proven efﬁcacy for reducing ﬁne lines and wrinkles,
moisturizing the skin, and improving ﬁrmness and skin tone.
A cream with pentapeptide-18 (0.05%) was compared in a study (43 women) with
acetylhexapeptide-3 (0.05%) and the combination of both peptides. Wrinkle reductions were
measured for pentapeptide-18, acetylhexapeptide-3, and a combination, at 11.64%, 16.26%, and 24.62%,
respectively. The pentapeptide-18 study mentioned a synergistic effect or an increase of efﬁciency,
by its association with acetylhexapeptide-3 [6,47]. The cellular pathway of both peptides is different.
Three concentrations (0.5%, 1%, and 2%) of Leuphasyl formulations were applied on 20 volunteers
for two months, at the level of mimic muscles in the eyebrows zone and in the periorbital zone [
To further evaluate anti-wrinkle effects, an
study with 22 females with an average age of 51,
was designed. Volunteers were injected botulinum toxin in the periorbital region combined with a
topical treatment twice daily for six months. In comparison with the control, acetyl hexapeptide-8
and pentapeptide-18 induced a 20% and 11% decrease on glutamate release, respectively, while their
combination caused a 40% reduction. In addition to the measured effects of each individual compound,
this indicates a synergistic activity. The topical treatment demonstrated a potentiated effect for
botulinum toxin treatment, and extended the anti-wrinkle beneﬁt on the skin .
-Ala-Pro-Dab-NHBn-2-Acetate), also named dipeptide diamino-
butyroyl benzylamide diacetate or SYN
-AKE, mimics the effect of waglerin-1, a peptide that is
found in the venom of the viper Tropidolaemus wagleri. Tripeptide-3 acts at the postsynaptic membrane,
and is a reversible antagonist of the acetylcholine receptor.
Tripeptide-3 has been tested in different preparations for topical application in animal models in
concentrations ranging from 1% to 4%. The results have been claimed as smoothing the appearance of
mimic wrinkles and expression lines, shortly after applying the preparation [
]. Research results show
that tripeptide-3 can reduce the appearance of wrinkles after 28 days by up to 52% when a 4% topical
solution is used . The results from a three-month study (37 female volunteers) demonstrated that
tripeptide-3 formulation treatment provided both immediate and long-term improvements in the
appearance of ﬁne and coarse wrinkles .
5. Enzyme Inhibitor Peptides
Enzyme inhibitor peptides directly or indirectly inhibit enzymes. Soy oligopeptides, silk ﬁbroin
peptide and rice peptides act on the skin cells. The above-mentioned peptides inhibit enzymes like
tTAT-superoxide dismutase, stimulate hyaluronan synthase 2, or in the case of soy oligopeptides,
This category of peptides shows promising results, however only very few or no in vivo studies
have been conducted. Hence, their relevance is still unclear.
5.1. Soybean Peptides
Soy oligopeptides are obtained from soybean proteins, consisting of 3–6 amino acids, mainly in the
size range of 300–700 kDa. Various biological activities of soybean oligopeptides have been identiﬁed,
such as antioxidant, blood pressure lowering, and blood lipid lowering effects. Topically applied soy
oligopeptides data showed signiﬁcantly increased Bcl-2 protein expression and decreased cyclobutane
pyrimidine dimers-positive cells, sunburn cells, apoptotic cells, p53 protein expression, and Bax protein
expressions in the epidermis of UVB-irradiated foreskin. Topically used soy oligopeptides seem to
protect human skin (nine healthy male volunteers) against UVB-induced photo damage .
Cosmetics 2017,4, 16 10 of 14
A pseudo-randomized study (10 women,
) with soybean peptide showed a
signiﬁcant increase in glycosaminoglycan and collagen synthesis. This study showed the anti-aging
potential of a soy peptide .
5.2. Silk Fibroin Peptide
Silk ﬁbroin peptide is derived from the silkworm Bombyx mori. Scientiﬁc results show inhibitory
inﬂammation and enhance the anti-inﬂammatory activity of tTAT-superoxide dismutase, which was
previously reported to effectively penetrate various cells and tissues, and exert anti-oxidative activity
in a mouse model of inﬂammation . No human in vivo efﬁcacy data are currently available.
5.3. Rice Peptides
After a specially processing rice bran protein, low molecular weight peptides (<3000 Da) were
obtained. Black rice oligopeptides were measured at approximately 1300 Da. These oligopeptides were
noted for inhibiting MMP (matrix metalloproteinase) activity and stimulated hyaluronan synthase
2 gene expression in human keratinocytes in a dose-dependent manner [
]. Three new identiﬁed
rice bran protein peptides had a C-terminal tyrosine residue, and exhibited signiﬁcant inhibitory
effects against tyrosinase-mediated monophenolase reactions. Additionally, one peptide called CT-2
(Leu-Gln-Pro-Ser-His-Tyr) potently inhibited melanogenesis in mouse melanoma cells without causing
cytotoxicity, which might be of interest for melanin-related skin conditions.
Rice bran protein is a potent source of tyrosinase inhibitory peptides [
]. Formulations containing
niosomes entrapped with rice bran bioactive compounds show clinical anti-aging properties [
However, there is currently no in vivo data for puriﬁed black rice oligopeptides available.
6. Peptides Derived from Structural Protein Digestion
Topical formulations containing keratin-based peptides are described to have hemostatic,
moisturizing, repair-promoting and potentially radio-protective properties. A placebo-controlled
study (nine healthy females with dry skin types III to V) tested keratin-based peptide
(molecular weight <1000 Da) (3%) vs. deionized water (3%) in a topical hand cream application
which was compared to untreated areas. Biophysical results of keratin-based peptide treatment
indicated skin improvement in water-holding capacity, hydration and elasticity. Results also indicated
that the keratin-based peptide cream treatment can prevent some of the damaging effects associated
with surfactant exposure [
]. Additional study results (six and 16 healthy females) with keratin
based peptide (3%) tested two different formulations (aqueous solution/internal wool lipid liposome
suspension). It was shown that topically applied keratin based peptide formulations again improved
the integrity and water-holding capacity of the skin barrier. Combining the keratin-based peptide with
internal wool lipids led to additional beneﬁcial effects [
]. The participant numbers were very low
and future studies should be carried out with more volunteers. No detailed information on the mode
of action of these peptides was available.
Twenty years ago, no scientist ever thought that the development or topical treatment of synthetic
or natural related peptides for cosmetic purposes would be so effective. Researchers identiﬁed peptide
sequences which allowed the peptides to be targeted to cosmetically important skin layers. Since 2000,
the use of peptides in cosmeceutical products has increased dramatically, and this highlights the
need to acquire in-depth knowledge of the different molecules as well as the physiological principles
underlying their use. The commercial potential for these molecules is high, especially for those peptide
sequences with cosmetic activity (e.g., anti-ageing, antioxidant, whitening). Nowadays, peptides can
Cosmetics 2017,4, 16 11 of 14
be developed or modiﬁed in numerous ways for solubility, better penetration, increased receptor
Selected peptides have excellent nontoxicity and stability records. Many of the studies shown in
this review, and a variety of additional observations, clearly show the wide range of possible topical
cosmetic applications of biologically active peptides, for improving the skin and its properties.
The overview also shows that there is still a lot of work required, and a lot of additional research
to perform. While many synthetic peptides with conﬁrmed efﬁcacy in skin treatment have been
researched to a satisfying extent, some of the mentioned clinical study results were obtained by
using formulations containing peptides and other active ingredients (for example: niacinamide and
vitamin C, E), or in the presence of a basic moisturizer. These clinical
trials did not differentiate
the role of the mentioned peptide speciﬁcally with other actives in the formulation. Hence, the observed
results cannot be claimed clearly to be the effect of the used peptide for enhanced skin beneﬁts and
improved skin appearance.
Additionally, there are many more peptides that are used in cosmetics. Their clinical studies
proving their efﬁcacy are not frequently published in scientiﬁc journals. Some clinical studies were
carried out with very few participant numbers, or through only a single study. These research results
seem to be very promising, but for efﬁcacy reasons, these peptides should be tested with a larger
number of participants.
While the long-known and well-researched peptides like Cu-GHK are still undergoing research to
obtain more details on their effectiveness and additional mechanisms of action, there are many other
interesting peptides whose effects should be more closely investigated.
The reported beneﬁcial clinical effects and the mode of action of a lot of peptides are not
Another aspect that hinders new innovations and peptide developments, is the non-existence of
newly developed and lesser researched peptides on the Chinese INCI (International Nomenclature of
Cosmetic Ingredients) list, presenting a signiﬁcant barrier for entering the Chinese market.
There are still some open questions, such as how it may be possible to surmount the barrier to
allow permeation of such compounds, and thereby enhance the concentrations delivered to the target
site in the dermis. New questions will lead to new study designs, and hopefully new answers and
solutions, and new cosmeceutical peptides.
Conﬂicts of Interest: The authors declare no conﬂict of interest.
Fields, K.; Falla, T.J.; Rodan, K.; Bush, L. Bioactive peptides: Signaling the future. J. Cosmet. Dermatol.
8–13. [CrossRef] [PubMed]
Pai, V.V.; Bhandari, P.; Shukla, P. Topical peptides as cosmeceuticals. Indian J. Dermatol. Venereol. Leprol.
83, 9–18. [CrossRef] [PubMed]
Fischer, E.; Fourneau, E. Ueber einige derivate des Glykocolls. Eur. J. Inorg. Chem.
4. Wieland, T.; Bodanszky, M. The World of Peptides; Springer: Berlin/Heidelberg, Germany, 1991.
Rahnamaeian, M.; Vilcinskas, A. Short antimicrobial peptides as cosmetic ingredients to deter dermatological
pathogens. Appl. Microbiol. Biotechnol. 2015,99, 8847–8855. [CrossRef] [PubMed]
Gorouhi, F.; Maibach, H. Role of topical peptides in preventing or treating aged skin. Int. J. Cosmet. Sci.
31, 327–345. [CrossRef] [PubMed]
Mitragotri, S. Modeling skin permeability to hydrophilic and hydrophobic solutes based on four permeation
pathways. J. Control. Release 2003,86, 69–92. [CrossRef]
Partidos, C.D.; Beignon, A.S.; Brown, F.; Kramer, E.; Briand, J.P.; Muller, S. Applying peptide antigens
onto bare skin: Induction of humoral and cellular immune responses and potential for vaccination.
J. Control. Release 2002,85, 27–34. [CrossRef]
Cosmetics 2017,4, 16 12 of 14
Lintner, K.; Peschard, O. Biologically active peptides: From a laboratory bench curiosity to a functional skin
care product. Int. J. Cosmet. Sci. 2000,22, 207–218. [CrossRef] [PubMed]
Kaczvinsky, J.R.; Grifﬁths, C.E.; Schnicker, M.S.; Li, J. Efﬁcacy of anti-aging products for periorbital wrinkles
as measured by 3-D imaging. J. Cosmet. Dermatol. 2009,8, 228–233. [CrossRef] [PubMed]
Emanuele, E.; Spencer, J.M.; Braun, M. An experimental double-blind irradiation study of a novel topical
product (TPF 50) compared to other topical products with DNA repair enzymes, antioxidants, and growth
factors with sunscreens: Implications for preventing skin aging and cancer. J. Drugs Dermatol.
Nino, M.; Iovine, B.; Santoianni, P. Carnosine and N-Acetylcarnosine Induce Inhibition of UVB Erythema in
Human Skin. J. Cosmet. Dermatol. Sci. Appl. 2011,1, 177–179. [CrossRef]
Loing, E. Unipex Innovations, Québec, Canada; Thiery Suere and Elisabeth Lamarque, Unipex Innovations,
Ramonville St. Agne, France, Triﬂuoroacetyl-Tripeptide-2 to Target Senescence for Anti-aging Beneﬁts.
Available online: http://www.cosmeticsandtoiletries.com/formulating/category/skincare/premium-
Triﬂuoroacetyl-Tripept (accessed on 22 April 2017).
Puig, A.; Antón, J.M.; Mangues, M. A new decorin-like tetrapeptide for optimal organization of collagen
ﬁbres. Int. J. Cosmet. Sci. 2008,30, 97–104. [CrossRef] [PubMed]
Safety Assessment of Palmitoyl Oligopeptides as Used in Cosmetics. Available online: http://www.cir-
safety.org/sites/default/ﬁles/palmit072012slr.pdf (accessed on 22 April 2017).
Fournial, A.; Mondon, P. New Cosmetic or Dermopharmaceutical Topical Use of a Mixture of a Ghk
Tripeptide and Gqpr Tetrapeptide. Available online: www.google.com/patents/WO2012164488A2?cl=en
(accessed on 22 April 2017).
Murphy-Ullrich, J.E.; Poczatek, M. Activation of latent TGF-beta by thrombospondin-1: Mechanisms and
physiology. Cytokine Growth Factor Rev. 2000,11, 59–69. [CrossRef]
Imfeld, D.; Jackson, E.; Heidl, M.; Campiche, R. Activation of tgf a gateway to skin rejuvenation small
synthetic-peptide mimics natural protein activity in skin to unlock tgf potential. H&PC Today-Househ. Pers.
Care Today 2015,10, 6–11.
Sanz, M.T.; Campos, C.; Milani, M.; Foyaca, M.; Lamy, A.; Kurdian, K.; Trullas, C. Biorevitalizing effect of a
novel facial serum containing apple stem cell extract, pro-collagen lipopeptide, creatine, and urea on skin
aging signs. J. Cosmet. Dermatol. 2016,15, 24–30. [CrossRef] [PubMed]
Herndon, J.H., Jr.; Jiang, L.; Kononov, T.; Fox, T. An Open Label Clinical Trial of a Multi-Ingredient Anti-Aging
Moisturizer Designed to Improve the Appearance of Facial Skin. J. Drugs Dermatol.
Lintner, K. Cosmetic or Dermopharmaceutical Use of Peptides for Healing, Hydrating and Improving
Skin Appearances during Natural or Induced Ageing (Heliodermia, Pollution). US Pattent 6,620,419, 16
Robinson, L.R.; Fitzgerald, N.C.; Doughty, D.G.; Dawes, N.C.; Berge, C.A.; Bissett, D.L. Topical palmitoyl
pentapeptide provides improvement in photoaged human facial skin. Int. J. Cosmet. Sci.
23. Guttman, C. Studies demonstrate value of procollagen fragment Pal-KTTKS. Dermatol. Times 2002,23, 68.
Mondon, P.; Hillion, M.; Peschard, O.; Andre, N.; Marchand, T.; Doridot, E.; Feuilloley, M.G.; Pionneau, C.;
Chardonnet, S. Evaluation of dermal extracellular matrix and epidermal-dermal junction modiﬁcations
using matrix-assisted laser desorption/ionization mass spectrometric imaging,
microscopy, echography, and histology: Effect of age and pepti. J. Cosmet. Dermatol.
Watson, R.E.; Ogden, S.; Cotterell, L.F.; Bowden, J.J.; Bastrilles, J.Y.; Long, S.P.; Grifﬁths, C.E. Effects of a
cosmetic ‘anti-ageing’ product improves photoaged skin. Br. J. Dermatol.
,161, 419–426. [CrossRef]
. Available online: http://www.webareal.com.ua/fotky27371/BIOPEPTIDE_EL_.pdf
(accessed on 22 April 2017).
Rodrigues, A.L.; Benoit, I.; Clarius, T.; Pauly, G. Counter acting Ageing Phenomena by New Pure
Tetrapeptides with Targeted Efﬁcacy. Cosmet. Sci. Technol. 2009,27, 63–71.
Cosmetics 2017,4, 16 13 of 14
Farwick, M.; Grether-Beck, S.; Marini, A.; Maczkiewitz, U.; Lange, J.; Köhler, T.; Lersch, P.; Falla, T.; Felsner, I.;
Brenden, H.; et al. Bioactive tetrapeptide GEKG boosts extracellular matrix formation:
molecular and clinical proof. Exp. Dermatol. 2011,20, 602–604. [CrossRef] [PubMed]
Farwick, M.; Maczkiewitz, U.; Lersch, P.; Summers, B.; Rawlings, A.V. Facial skin-lightening beneﬁts of the
tetrapeptide Pro-Lys-Glu-Lys on subjects with skin types V-VI living in South Africa. J. Cosmet. Dermatol.
2011,10, 217–223. [CrossRef] [PubMed]
Marini, A.; Farwick, M.; Grether-Beck, S.; Brenden, H.; Felsner, I.; Jaenicke, T.; Weber, M.; Schild, J.;
Maczkiewitz, U.; Köhler, T.; et al. Modulation of skin pigmentation by the tetrapeptide PKEK:
and in vivo evidence for skin whitening effects. Exp. Dermatol. 2012,21, 140–146. [CrossRef] [PubMed]
Gruber, J.V.; Ludwig, P.; Holtz, R. Modulation of cellular senescence in ﬁbroblasts and dermal papillae cells
in vitro. J. Cosmet. Sci. 2013,64, 79–87. [PubMed]
32. Linder, J. The science behind peptides. Plast. Surg. Nurs. 2012,32, 71–72. [CrossRef] [PubMed]
33. Pickart, L.; Schagen, S. New data of the Cosmeceutical and tripeptide GHK. SOFW J. 2015,9, 141.
Campbell, J.D.; McDonough, J.E.; Zeskind, J.E.; Hackett, T.L.; Pechkovsky, D.V.; Brandsma, C.A.; Suzuki, M.;
Gosselink, J.V.; Liu, G.; Alekseyev, Y.O.; et al. A gene expression signature of emphysema-related lung
destruction and its reversal by the tripeptide GHK. Genome Med. 2012,4, 67. [PubMed]
Kerscher, M.; Buntrock, A. Update in der dermatologischen Kosmetik (Update on cosmeceuticals). JDDG
2011,9, 314–328. [PubMed]
Leyden, J.J.; Stevens, T.; Finkey, M.B.; Barkovic, S. Skin care beneﬁts of copper peptide containing facial
cream. In Proceedings of the American Academy of Dermatology 60th Annual Meeting, New Orleans, LA,
USA, 22–27 February 2002; p. 29.
Pickart, L.; Vasquez-Soltero, J.M.; Margolina, A. GHK Peptide as a Natural Modulator of Multiple Cellular
Pathways in Skin Regeneration. BioMed Res. Int. 2015,2015. [CrossRef] [PubMed]
Jose, S.; Hughbanks, M.L.; .Binder, B.Y.; Ingavle, G.C.; Leach, J.K. Enhanced trophic factor secretion
by mesenchymal stem/stromal cells with Glycine-Histidine-Lysine (GHK)-modiﬁed alginate hydrogels.
Acta Biomater. 2014,10, 1955–1964. [CrossRef] [PubMed]
Abdulghani, A.; Sherr, A.; Shirin, S.; Solodkina, G.; Tapia, E.; Wolf, B.; Gottlieb, A. Effects of topical
creams containing vitamin C, a copper-binding peptide cream and melatonin compared with tretinoin
on the ultrastructure of normal skin—A pilot clinical, histologic, and ultrastructural study. Dis. Manag.
Clin. Outcomes 1998,1, 136–141. [CrossRef]
Finkley, M.; Appa, Y.; Bhandarkar, S. Copper Peptide and Skin Cosmeceuticals and Active Cosmetics: Drugs vs.
Cosmetics; Elsner, P., Maibach, H., Eds.; Marcel Dekker: New York, NY, USA, 2005; pp. 549–563.
Hussain, M.; Goldberg, D.J. Topical manganese peptide in the treatment of photodamaged skin. J. Cosmet.
Laser Ther. 2007,9, 232–236. [CrossRef] [PubMed]
Ruiz, M.A.; Clares, B.; Morales, M.E.; Cazalla, S.; Gallardo, V. Preparation and stability of cosmetic
formulations with an anti-aging peptide. J. Cosmet. Sci. 2007,58, 157–171. [CrossRef] [PubMed]
Krishnan, G.; Roberts, M.S.; Grice, J.; Anissimov, Y.G.; Moghimi, H.R.; Benson, H.A. Iontophoretic skin
permeation of peptides: An investigation into the inﬂuence of molecular properties, iontophoretic conditions
and formulation parameters. Drug Deliv. Transl. Res. 2014,4, 222–232. [CrossRef] [PubMed]
Blanes-Mira, C.; Clemente, J.; Jodas, G.; Gil, A.; Fernández-Ballester, G.; Ponsati, B.; Gutierrez, L.;
Pérez-Payá, E.; Ferrer-Montiel, A. A synthetic hexapeptide (Argireline) with antiwrinkle activity. Int. J.
Cosmet. Sci. 2002,24, 303–310. [CrossRef] [PubMed]
Wang, Y.; Wang, M.; Xiao, S.; Pan, P.; Li, P.; Huo, J. The anti-wrinkle efﬁcacy of argireline, a synthetic
hexapeptide, in Chinese subjects: A randomized, placebo-controlled study. Am. J. Clin. Dermatol.
147–153. [CrossRef] [PubMed]
Zhmak, M.N.; Utkin, Y.N.; Andreeva, T.V.; Kudryavtsev, D.S.; Kryudova, E.V.; Tsetlin, V.I.; Shelukhina, I.V.E.
Peptide Inhibitors of Nicotinic Acetylcholine Receptor. US Patent US 20,150,361,137 A1, 17 December 2015.
Leuphasyl a New Pentapeptide for Expression Wrinkles. Available online: http://docplayer.net/15401907-
peptide-for-cosmetic-applications.html (accessed on 19 December 2016).
Dragomirescu, A.O.; Andoni, M.; Ionescu, D.; Andrei, F. The Efﬁciency and Safety of Leuphasyl—A
Botox-Like Peptide. Cosmetics 2014,1, 75–81. [CrossRef]
Cosmetics 2017,4, 16 14 of 14
Rull, M.; Davi, C.; Cañadas, E.; Almiñana, N.; Delgado, R. Peptide Approach to Enhance Anti-wrinkle
Efﬁcacy Between Injections. Available online: http://www.cosmeticsandtoiletries.com/formulating/
273052431.html (accessed on 15 May 2017).
Chhipa, N.M.R.; Chaudhari, B. Toxin as a Medicine. Available online: https://www.researchgate.net/proﬁle/
(accessed on 22 April 2017).
Trookman, N.S.; Rizer, R.L.; Ford, R.; Ho, E.; Gotz, V. Immediate and Long-term Clinical Beneﬁts of a Topical
Treatment for Facial Lines and Wrinkles. J. Clin. Aesthet. Dermatol. 2009,2, 38–43. [PubMed]
Zhou, B.R.; Ma, L.W.; Liu, J.; Zhang, J.A.; Xu, Y.; Wu, D.; Permatasari, F.; Luo, D. Protective Effects of Soy
Oligopeptides in Ultraviolet B-Induced Acute Photodamage of Human Skin. Oxid. Med. Cell. Longev.
2016. [CrossRef] [PubMed]
Andre-Frei, V.; Perrier, E.; Augustin, C.; Damour, O.; Bordat, P.; Schumann, K.; Förster, T.; Waldmann-Laue, M.
A comparison of biological activities of a new soya biopeptide studied in an
skin equivalent model
and human volunteers. Int. J. Cosmet. Sci. 1999,21, 299–311. [CrossRef] [PubMed]
Kim, D.W.; Hwang, H.S.; Kim, D.S.; Sheen, S.H.; Heo, D.H.; Hwang, G.; Kang, S.H.; Kweon, H.; Jo, Y.Y.;
Kang, S.W.; et al. Effect of silk ﬁbroin peptide derived from silkworm Bombyx mori on the anti-inﬂammatory
effect of Tat-SOD in a mice edema model. BMB Rep. 2011,44, 787–792. [CrossRef] [PubMed]
Sim, G.S.; Lee, D.H.; Kim, J.H.; An, S.K.; Choe, T.B.; Kwon, T.J.; Pyo, H.B.; Lee, B.C. Black rice (Oryza sativa L.
var. japonica) hydrolyzed peptides induce expression of hyaluronan synthase 2 gene in HaCaT keratinocytes.
J. Microbiol. Biotechnol. 2007,17, 271–279. [PubMed]
Ochiai, A.; Tanaka, S.; Tanaka, T.; Taniguchi, M. Rice bran protein as a potent source of Antimelanogenic
peptides with tyrosinase inhibitory activity. J. Nat. Prod. 2016,79, 2545–2551. [CrossRef] [PubMed]
Manosroi, A.; Chutoprapat, R.; Abe, M.; Manosroi, W.; Manosroi, J. Anti-aging efﬁcacy of topical formulations
containing niosomes entrapped with rice bran bioactive compounds. Pharm. Biol.
Barba, C.; Méndez, S.; Roddick-Lanzilotta, A.; Kelly, R.; Parra, J.L.; Coderch, L. Wool peptide derivatives for
hand care. J. Cosmet. Sci. 2007,58, 99–107. [CrossRef] [PubMed]
Barba, C.; Méndez, S.; Roddick-Lanzilotta, A.; Kelly, R.; Parra, J.L.; Coderch, L. Cosmetic effectiveness of
topically applied hydrolysed keratin peptides and lipids derived from wool. Skin Res Technol.
243–248. [CrossRef] [PubMed]
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