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Bakuchiol: A Retinol-Like Functional Compound Revealed by Gene Expression Profiling & Clinically Proven to have Anti-Aging Effects.

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The study was undertaken to compare the skin care related activities of retinol and bakuchiol, a potential alternative to retinoids. Retinol is a pivotal regulator of differentiation and growth of developing as well as adult skin. Retinoic acid is the major physiologically active metabolite of retinol regulating gene expression through retinoic acid receptor - dependant and independent pathways. Comparative gene expression profiling of both substances in the EpiDerm FT full thickness skin substitute model was undertaken. Type I, III and IV collagen and aquaporin 3 synthesis in normal human dermal fibroblasts and in were analysed by ELISA and/or histochemistry in EpiDerm FT full thickness skin model were determined. Bakuchiol is a meroterpene phenol abundant in seeds and leaves of the plant Psoralea corylifolia. We present evidence that bakuchiol, having no structural resemblance to retinoids, can function as a functional analogue of retinol. Volcano plots show the great similarity of retinol and bakuchiol gene expression. Retinol-like functionality was further confirmed for the upregulation of types I, and IV collagen in DNA microarray study and also show stimulation of type III collagen in the mature fibroblast model. Bakuchiol was also formulated into a finished skin care product and was tested in clinical case study by twice-a-day facial application. The results showed that, after twelve weeks treatment, significant improvement in lines and wrinkles, pigmentation, elasticity, firmness and overall reduction in photo-damage was observed, without usual retinol therapy-associated undesirable effects. Based on these data, we propose that bakuchiol can function as an anti-aging compound through retinol-like regulation of gene expression. This article is protected by copyright. All rights reserved.
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Bakuchiol: a retinol-like functional compound revealed by gene
expression profiling and clinically proven to have anti-aging effects
R. K. Chaudhuri* and K. Bojanowski
*Sytheon Ltd., Boonton, NJ 07005, USA and
Sunny Biodiscovery, Santa Paula, CA 93060, USA
Received 04 November 2013, Accepted 25 January 2014
Keywords: anti-ageing clinical, bakuchiol, DNA microarray, histology, retinol
Synopsis
OBJECTIVE: The study was undertaken to compare the skin care
related activities of retinol and bakuchiol, a potential alternative to
retinoids. Retinol is a pivotal regulator of differentiation and
growth of developing as well as adult skin. Retinoic acid is the
major physiologically active metabolite of retinol regulating gene
expression through retinoic acid receptor dependant and indepen-
dent pathways.
METHODS: Comparative gene expression profiling of both sub-
stances in the EpiDerm FT full thickness skin substitute model
was undertaken. Furthermore, type I, III and IV collagen, as well
as aquaporin 3 expression was analyzed by ELISA and/or histo-
chemistry in human dermal fibroblasts and/or Epiderm FT skin
substitutes.
RESULTS: Bakuchiol is a meroterpene phenol abundant in seeds
and leaves of the plant Psoralea corylifolia. We present evidence that
bakuchiol, having no structural resemblance to retinoids, can func-
tion as a functional analogue of retinol. Volcano plots showed
great overall similarity of retinol and bakuchiol effects on the gene
expression profile. This similarity was confirmed by the side-by-side
comparison of the modulation of individual genes, as well as on
the protein level by ELISA and histochemistry. Retinol-like func-
tionality was further confirmed for the upregulation of types I and
IV collagen in DNA microarray study and also show stimulation of
type III collagen in the mature fibroblast model. Bakuchiol was also
formulated into a finished skin care product and was tested in clini-
cal case study by twice-a-day facial application. The results showed
that, after 12 weeks treatment, significant improvement in lines
and wrinkles, pigmentation, elasticity, firmness and overall reduc-
tion in photo-damage was observed, without usual retinol therapy-
associated undesirable effects.
CONCLUSION: Based on these data, we propose that bakuchiol
can function as an anti-ageing compound through retinol-like
regulation of gene expression.
R
esum
e
OBJECTIF: L’
etude a
et
e men
ee pour comparer les activit
es li
ees
aux soins de la peau du r
etinol et du bakuchiol, une alternative
potentielle aux r
etino
ıdes. Le r
etinol est un r
egulateur essentiel de
la diff
erenciation et de la croissance de la peau en d
eveloppement
ainsi que la peau des adultes. L’acide r
etino
ıque est le principal
m
etabolite physiologiquement actif du r
etinol qui r
egule l’expres-
sion des g
enes par des voies d
ependantes et ind
ependantes du
r
ecepteur de l’acide r
etino
ıque.
M
ETHODES: Un profilage comparatif d’expression g
en
etique de ces
deux substances dans le mod
ele substitut de la peau EpiDerm FT a
et
e entrepris. La synth
ese des collag
enes de type I, III et IV et de
l’aquaporine 3 dans des fibroblastes dermiques humains normaux
ont
et
e analys
es par ELISA et/ou en histochimie dans le mod
ele de
peau EpiDermTM FT.
R
ESULTATS: Bakuchiol est un ph
enol meroterp
ene abondant dans
les graines et les feuilles de la Psoralea corylifolia. Nous pr
esentons
des preuves que bakuchiol, n’ayant aucune ressemblance structu-
relle avec les r
etino
ıdes, peut fonctionner comme un analogue fonc-
tionnel de r
etinol. Les diagrammes de type Volcano montrent la
grande similitude de l’effet du r
etinol et du bakuchiol sur l’expres-
sion des g
enes. Cette ressemblance a
et
e aussi d
emontr
ee par la
comparaison de la modulation de l’expression de g
enes particu-
laires, appartenant a de diff
erentes groupes fonctionnelles. La fonc-
tionnalit
er
etinol -like a
et
e confirm
ee par la r
egulation
a la hausse
du collag
ene de type I et IV et aquaporine 3 au niveau de proteines
par ELISA et histochimie. Le bakuchiol a
egalement
et
e formul
e
dans un produit de soin de la peau et a
et
e test
e dans une
etude
clinique avec deux applications par jour au visage. Les r
esultats
ont montr
e que, apr
es le traitement de douze semaines, une
am
elioration significative a
et
e observ
ee dans les rides et ridules, la
pigmentation, l’
elasticit
e, la fermet
eetlar
eduction globale des
dommages du photo-vieillissement, sans les effets ind
esirables habi-
tuels associ
es
alath
erapie au r
etinol.
CONCLUSION: Sur la base de ces donn
ees, nous proposons que le
bakuchiol peut fonctionner comme un compos
e anti- vieillissement
gr^
ace
alar
eglementation de l’expression des g
enes similaire au
r
etinol.
Introduction
Retinoids have been first defined as a family of naturally occurring
compounds comprised of vitamin A (retinol) and its derivatives,
such as vitamin A aldehyde (retinal) or vitamin A acid (retinoic
acid). Retinoic acid is considered to be the active form of vitamin A
and is involved in gene regulation, leading to effects ranging from
hyperplasia to differentiation and apoptosis of normal and cancer
cells [1, 2]. The conversion of retinol to retinal by the retinol dehy-
drogenases is considered to be the rate-limiting step for the biosyn-
thesis of retinoic acid [3]. In addition to retinol dehydrogenases,
P450s 1A1, 1A2, 1B1 and 3A4 have been shown to be involved
Correspondence: Ratan K. Chaudhuri, Sytheon Ltd., 315 Wootton
Street, Boonton, NJ 07005, USA. Tel.: +201 303 5594; fax: +1 973
909 9922; e-mail: ratan@sytheonltd.com
©2014 Society of Cosmetic Scientists and the Soci
et
e Franc
ßaise de Cosm
etologie 1
International Journal of Cosmetic Science, 2014, 1–10 doi: 10.1111/ics.12117
in the metabolism of retinoic acid [4]. Human dermal fibroblasts
treated with retinol metabolize it to retinoic acid, demonstrating
the bioactivity and bioavailability of retinol in the dermis [5].
Retinol is found in a variety of foods such as beef, calf, chicken
liver, eggs and fish. It is also present in vegetables such as carrots,
squash, sweet potatoes, pumpkin and cantaloupe. Subsequent
research has resulted in a much larger class of natural and syn-
thetic compounds that are termed retinoids due to their functional
although not always structural similarity to vitamin A [6].
The epidermis is one of the major targets for the retinoic acid
signalling in adult organism. Classic retinoid activities are mainly
achieved through the transcriptional regulation of specific genes
via two classes of nuclear hormone receptors, the retinoic acid
receptors (RAR) and retinoid X receptors (RXR), each with three is-
otypes (a,b,c) and multiple isoforms [79]. All-trans retinoic acid
preferentially binds RARs and its 9-cis isomer, 9-cis retinoic acid,
binds both RARs and RXRs. The predominant retinoid receptors
found in skin are RARcand RXRa[10]. Retinoic acid receptors
exert their effects in epidermis through direct binding to epidermal
genes [11, 12] or interference with signalling of other transcription
factors [13].
Retinoic acid and its derivatives have been used as therapeutic
agents for numerous skin conditions from psoriasis to acne and
were also found to be clinically effective against wrinkles [14].
Retinol (Fig. 1A) application is believed to be a more efficient
method to deliver retinoic acid to the skin cells than direct treat-
ment with retinoic acid [15]. However, retinoid therapy using
even the newer analogues is still restricted by many undesirable
side effects, such as irritation, dryness, peeling, erythema and a
sensation of burning on the skin [16, 17]. These side effects often
result in non-compliance and discontinuation of therapy. There-
fore, there is a definite need to develop improved retinoid com-
pounds. Such compounds should have similar but not identical
gene expression pattern as compared with retinol, ideally, result-
ing in retinol-like beneficial effects, without having retinol-like
undesirable side effects. Here, we build on our preliminary findings
[18] and report that bakuchiol (Fig. 1B) a meroterpene phenol
from seeds of the plant Psoralea corylifolia [19, 20] exhibits such
retinol-like functionality.
Materials and methods
Test materials
Retinol (Fig. 1A), trade named Retinol 50 C (INCI name Retinol
and Polysorb 20), was purchased from BASF (Florham Park, NJ,
U.S.A). This product is a yellow oil containing 50% vitamin A in
polysorbate 20 and stabilizer system consisting of 3.5% BHT and
1% BHA. Bakuchiol (Phenol, 4-[1E,3S)-3-ethenyl-3,7-dimethyl-1,6-
octadinenyl; Fig. 1B)l is a phenolic compound with a monoterpene
side chain [19]. Bakuchiol belongs to a rare group of terpenoids in
which the aromatic ring system is derived from phenylpropane unit.
The material used in this study is obtained from edible seeds of Psora-
lea corylifolia, which is psoralene-depleted Bakuchiol (trade named Sy-
tenol
â
A; INCI name Bakuchiol) with a purity of about 95%.
DNA microarrays
EpiDerm FT tissues were obtained from Mattek (Ashland, MA,
U.S.A.; cat. no. EFT 212) and cultured according to the manu-
facturer’s instructions. The test materials Retinol (50%) and
Bakuchiol (100%) were dissolved in DMSO at 10 mg mL
1
(Reti-
nol) and 5 mg mL
1
(Bakuchiol), and further dilutions were made
in type I sterile water. Test materials were assayed at 10 lgmL
1
(Retinol) and 5 lgmL
1
(Bakuchiol) against 0.1% DMSO as a con-
trol. The incubation time with skin tissues was 2 days. After incu-
bation, skin tissues were harvested, frozen in liquid nitrogen and
subjected to total RNA extraction with Qiagen kit (Frederick, MD,
U.S.A). The quality of extracted RNA was validated twice by elec-
trophoresis (after extraction and before microarray analysis).
Samples were hybridized and data were analysed using human
OneArray platform from Phalanx Biotech (Palo Alto, CA, U.S.A.).
The Excel file yielding information on over 30 000 probes was then
further processed in house to retain only differences with low P
values (Pvalue cut off was 0.05) and high fold-change (the cut off
value for fold-change was 2.0).
Collagen ELISA
Retinol and bakuchiol were assayed at 10 lgmL
1
on normal
human fibroblasts grown in DMEM with 5% calf serum (Hyclone,
Salt Lake City, UT, U.S.A.). For type I and IV collagen quantifica-
tion, neonatal human dermal fibroblasts (low passage; American
Type Culture Collection, Manassas, VA, U.S.A. cat. no. PCS-201-
010, lot no. 58243223) were used. For type III collagen quantifi-
cation, human epidermal fibroblasts from a 68-year-old female
donor (p. 5, Zen-bio, cat. no. KR-F) was used. Cells were exposed
to test materials for 3 days (type I collagen quantification) or
7 days (type III and IV collagen quantification). Afterward, cell-
culture conditioned media were harvested and assayed for type I,
type III or type IV collagen by sandwich ELISA using affinity-purified
antibodies, followed by streptavidin-avidin-HRP conjugate and ABTS,
according to a standard ELISA protocol [21, 22]. The colorimetric
signal proportional to collagen content was quantified with the Bio-
Rad microplate spectrophotometer 3550-UV at 405 nm with back-
ground subtraction at 660 nm and analysed with Microplate
Manager v.2 software for Macintosh (BioRad, Hercules, CA, U.S.A.).
Histochemistry
Fort type IV collagen and aquaporin three visualization retinol
and bakuchiol were dissolved at 50 mg mL
1
in DMSO. Test sam-
ples were then further diluted in type I sterile water and tested at
final concentrations 10 lgmL
1
(Retinol) and 5 lgmL
1
(Bak-
uchiol) using EpiDermFT tissues from Mattek. Tissues were equili-
brated for 24 h and incubated with test materials or water
(negative control) for 96 h, afterward they were rinsed and fixed
in 10% buffered formalin. Paraffin sections of these tissues were
stained with a biotinylated antibody against type IV collagen (cat.
B
A
HO
OH
Figure 1 (A) Retino l. (B) Bakuchiol.
2©2014 Society of Cosmetic Scientists and the Soci
et
e Franc
ßaise de Cosm
etologie
International Journal of Cosmetic Science, 1–10
A retinol-like functional compound R. K. Chaudhuri and K. Bojanowski
no. 1340-08 Southern Bio, Birmingham, AL, U.S.A.) or AQP3
(cat. no. sc-9885, Santa Cruz Biotechnology, Santa Cruz, CA,
U.S.A.) and developed with the ABC peroxidase staining compo-
nents (Santa Cruz Biotechnology). Slides were mounted in Perm-
mount and observed on Nikon (Tokyo, Japan) Eclipse TS100
inverted microscope at 100 magnifications. Microphotographs
were taken with Canon Rebel digital camera mounted on the
Nikon TS100 microscope.
Clinical study
General
Seventeen healthy but photo-aged subjects were recruited to this
blind study (all females; age range 4065 years). All subjects read,
understood and signed an informed consent. All subjects had
abstained from the use of moisturizing products and used only sim-
ple soap, for at least 1 week prior to treatment conditions. All test
products were supplied in identical containers. Subjects were
instructed on the use of the cream twice daily morning and even-
ing applications to the entire face for 3 months. Clinical assess-
ments of the skin of the face were performed for all participants at
baseline and following 4, 8 and 12 weeks of product use. The fol-
lowing parameters were assessed at each visit by an expert grader:
Fine Lines/Wrinkles, Roughness and Dryness, Skin Tone, Skin Elas-
ticity and Firmness, Radiance, Brightening and Overall Eye Area
Appearance. Assessment for each parameter was performed at
baseline using the following five-point ordinal severity scale:
0=None; 1 =Minimal; 2 =Mild; 3 =Moderate; 4 =Severe.
Silicone analysis profilometry
At each visit, a single silicone replica was made of the target area
and a photographic record was kept of this target for subsequent
relocation. Comparative analysis of skin profilometry was con-
ducted, using surface roughness and wrinkle depth analysis. The
heights of the replicated wrinkles were measured using Miyomoto
Surftest profilometer. Ry (depth) and Ra (mean roughness) were
recorded at each time of measuring operation. The area scanned
from each sample was clearly mapped so as to determine the same
area in respective weeks 4, 8 and 12 samples.
Photo booth
At each time point, a series of high resolution digital photographs
was collected using a photo booth equipped with Canon G7 Digital
Camera 10 MP, 69zoom. Subject positioning was reproduced
upon return visit. A light booth was used so as to provide con-
trolled reproducible light conditions. The booth consists of an array
of 8 equally spaced fluorescent tubes in a semicircular configura-
tion. The software-driven system allows the position and expression
of the test subjects to be aligned to a high degree.
Method of assessment & product application
Baseline
The expert grader performed assessment of the panelist’s face and
eye area for all the parameters as described before. Photographs
were conducted using a photo booth with a three-point head
restraint with photographs taken with frontal view, 45 degrees to
the right and 45 degrees to the left at each time point (Day 0,
Weeks 4, 8 and 12). A replica ring was used to delineate the wrin-
kle site in the crow’s feet area. Silflo was applied on the site,
allowed to dry for approximately 5 min, and the replica was
removed gently from the site.
Product application
Test Materials were distributed to the subjects. Subjects were asked to
gently massage a small amount of the test material to the crow’s feet
and eye area and then smooth over the whole face. They were asked
to apply twice a day for 12 weeks. A study diary was given to the
panelists to list the time of application, the dates and any subjective
comments that they might have in regard to the test product.
Weeks 4, 8 and 12
Panellists returned to the study site after week 4, 8 and 12 of prod-
uct use. At each study visit, panellists were clinically evaluated in
the same manner as at the baseline visit.
Statistical analysis
For each of the parameters, percent improvement from baseline
was calculated to express the efficacy of the product at each time
point (4, 8 and 12 weeks). Using the t-test, the statistical signifi-
cance of the net change from baseline (pre-application) to each
subsequent time point was assessed. Statistical significance was
defined at the P=0.05 or less level (corresponding to a 95% or
greater confidence level).
Formulated product
Formulation details are given in Table V.
Results and discussion
Bakuchiol is a meroterpene phenol abundant in seeds and leaves of
the plant Psoralea corylifolia [19, 20] and has also been isolated
from other plants, such as, P. grandulosa [23, 24], P. drupaceae
[25], Ulmus davidiana [26], Otholobium pubescens [27] and Piper lon-
gum [28]. It is widely used in Indian as well as Chinese medicine to
treat a variety of diseases. Bakuchiol has been reported to possess
anti-inflammatory [24, 2931], antioxidant [3234], anti-tumor
[35, 36], anti-bacterial [37], cytotoxic [38], heptaprotective [39]
and caspase-3 depended apoptosis [40] effects. The cytotoxicity of
bakuchiol is mainly due to its DNA polymerase 1-inhibiting activity
[41]. Recently, anti-acne activity of bakuchiol has been reported
[42]. Here, we demonstrate the anti-ageing and retinol-like func-
tionalities of bakuchiol using DNA microarray, ELISA, histochemis-
try and clinical case studies.
As human skin naturally ages, it becomes thin, lax and finely
wrinkled. Of these changes, fine lines & wrinkles and uneven pig-
mentation are most easily appreciated clinically with severity corre-
lating strongly with age. We have demonstrated through a pilot
clinical study that topical 0.5% bakuchiol treatment improves clini-
cal appearance (% improvement vs. baseline) of naturally aged/
photo-aged human skin.
DNA microarrays
As retinol affects the expression of a vast array of genes, compara-
tive gene expression profiling with retinol is a suitable method to
identify retinol-like compounds [43]. Here, we applied this method
©2014 Society of Cosmetic Scientists and the Soci
et
e Franc
ßaise de Cosm
etologie 3
International Journal of Cosmetic Science, 1–10
A retinol-like functional compound R. K. Chaudhuri and K. Bojanowski
to reveal retinol-like properties of bakuchiol. These proprieties were
first evidenced on the whole genome scale by comparing the shapes
of volcano plots of retinol- and bakuchiol-treated skin substitutes
(Fig. 2A,B). Volcano plot is a scatter graph used to identify mean-
ingful changes in large datasets, such as data from DNA micro-
array analysis, by plotting significance versus. fold-change on the
y- and x-axes, respectively. Data points with low P-values (highly
significant) appear towards the top of the plot, and with Pvalue of
0.05 being set as the threshold for statistical significance, all points
situated above the value of 1.3 on the y axis are statistically signifi-
cant. The finding that the overall shapes of retinol and bakuchiol
volcano plots are similar was the first indication of the functional
analogy between the two compounds. This was further confirmed
by the analysis of retinoid-binding and metabolizing genes; the
expression was often but not always similarly modulated
(Table I). Interestingly, both RARB and RARG are up-regulated, as
expected, by retinol but not by bakuchiol, indicating a possible
advantage of the latter in terms of side effects. Also retinol had no
effects on CRBP II and CRBP IV, whereas bakuchiol showed signifi-
cantly higher up-regulation. Furthermore, retinol causes down reg-
ulation of CRABP1 gene whereas bakuchiol causes up-regulation,
and whereas bakuchiol showed a dramatic up-regulation (82-fold
vs. placebo) of LRAT retinol showed 12.3-fold (still a very signifi-
cant) increase. These results indicate that besides being a retinol
functional analogue, bakuchiol may enhance the availability of
endogenous retinol.
Retinol and bakuchiol also showed similar modulation of genes
implicated in ECM and DEJ (Tables II and III, respectively). ECM is
the material that forms the bulk of the dermis, excluding water and
cells. Proteins and complex sugars form most of the dermal ECM, and
they are arranged in an orderly network fibres and ground sub-
stances organized by physical entanglements, opposing ionic
charges, chemical covalent bonding and cross-linking into a
biomechanically active polymer. This scaffolding structure with
regional tensile strength provided by collagens, elasticity by elastins,
Table I Description, fold-change in the DNA microarray experiment and role of modulated retinoid binding and metabolizing genes (R: retinol; B: bakuchiol)
Gene Full name Function & comments
CRBP I;
CRBP II;
CRBP IV
Cellular retinol binding
protein I, II & IV
CRBP I:R =2.6; B =4.2
CRBP II: R =NS; B =4.1
CRBP IV: R =NS; B =3.1
CRBP I mediates the cellular uptake of retinol, solubilizes and detoxifies it for further transport within the
cytoplasm and presents it to the appropriate enzymes to biosynthesize retinoic acid
N6AMT2 N-6 adenine-specific
DNA methyltransferase 2
R=NS; B =2.1
Retinoic acid resistance might be overcome by the use of epigenetic modifying agents such as DNA methyl
transferase inhibitors. Down-regulation provided by bakuchiol may reduce retinoic acid-induced toxicity
TIG1 Tazarotene-inducible gene 1 R =13.2; B =12.9
Retinoid acid (RA) receptor-responsive gene. The expression of this gene is found to be down-regulated in a
variety of human cancers as well as in acne, rosacea and psoriasis. Up-regulation by bakuchiol may provide a
solution to problem skin. Anti-acne clinical study results of bakuchiol has recently been reported [40]
DHRS9 Dehydrogenase/reductase
SDR family member
9 precursor
R=5.5; B =11.6
DHRS9 is involved in converting retinol to retinal and then to retinoic acid, the rate-limiting step for the
biosynthesis of retinoic acid
RETSAT All-trans- 13,14-dihydroretinol
saturase
R=2.9; B =2.8
RETSAT expression is involved in adipocyte differentiation
LRAT Lecithin-retinol acyltransferase R =12.3; B =82.2
Retinol esterification with long-chain fatty acid by LRAT is the key step in both absorption & storage of retinol.
CYP1A1;
CYP1A2
Cytochrome P450 CYP1A1: R =4.0; B =4.9
CYP1A2: R =3.6; B =6.7
In addition to retinol dehydrogenase, P450s 1A1 and 1A2 genes are the major human P450s
RARB; RARG Retinoic acid receptor beta -1;
Retinoic acid receptor
gamma -1
RARB: R =5.6; B =NS
RARG: R =1.8; B =NS
The actions of retinoids are generally mediated by the retinoic acid receptors (RARs alpha, beta, and gamma) and
the retinoid X receptors (RXRs alpha, beta, and gamma). Both RARB and RARG are up-regulated, as expected
by retinol but not with bakuchiol
0
2
4
6
–3 –2 –1 0 1 2 3
–Log (P value)
Log2 (fold change)
Retinol
0
2
4
6
–3 –2 –1 0 1 2 3
–Log (P value)
Log2 (fold change)
Bakuchiol
A
B
Figure 2 (A) Volcan ic plot of DNA microarray data Retinol. (B) Volcanic
plot of DNA microarray data Bakuchiol.
4©2014 Society of Cosmetic Scientists and the Soci
et
e Franc
ßaise de Cosm
etologie
International Journal of Cosmetic Science, 1–10
A retinol-like functional compound R. K. Chaudhuri and K. Bojanowski
adhesiveness by structural glycoproteins, compressibility by proteo-
glycans hyaluronans and communicability by transmembrane
receptors, such as integrins, which exchange information between
the cytoskeleton-bound cellular elements and between cells and the
dermal extracellular matrix, provides a unique homeostatic tenseg-
rity function to the skin [44, 45]. DEJ, in turn, provides cohesion
between dermis and epidermis. With age, both, ECM and DEJ
gradually deteriorate resulting in skin thinning and morphological
Table II Description, fold-change in the DNA microarray experiment and roles of modulated genes coding for ECM components [(R: retinol; B: bakuchiol]
Gene Full name Function & comments
COL1A2;
COL4A6;
COL9A2;
COL9A3;
Collagen 1A2;
Collagen 4A6;
Collagen 9A2;
Collagen 9A3
COL1A2: R =3.3; B =1.9
COL4A6: R =6.4; B =11.2
COL9A2: R =5.6; B =6.7
COL9A3: R =4.1; B =5.8
Collagens provide scaffolding structure with regional tensile strength and elasticity; Degradation leads to fine lines and
wrinkles. Comparable fold-change observed with four collagen genes with the exception of COL3A1. This may be due
to the use of neonatal tissue in the skin substitutes. ELISA study with mature fibroblasts showed stimulation of type III
collagen.
EMILIN3
EMILIN1
Elastin microfibril
interface-located protein 3;
Elastin microfifibril
interface-located protein 1
EMILIN3:R =2.2 (NS); B =9.1
EMILIN1: R =3.4; B =2.4
The EMILINs are a family of glycoproteins of the extracellular matrix; Widely distributed in several tissues associated
with elastin and localized at the interface between amorphous elastin and microfibrils
PI3 Peptidase inhibitor
3/Elastase-specific inhibitor
R=2.5; B =2.7
Bakuchiol and retinol are expected to maintain the desired level of elastin required for maintaining the connective
tissue structure due to their up-regulation of elastase-specific inhibitor gene PI3
FLRT2;
FLRT3
Fibronectin-like
domain-containing
leucine-rich transmembrane
protein 2
FLRT2: R =NS; B =13.9
FLRT3: R =2.8 (NS); B =6.1
Fibronectins maintain the shape of cells and matrix stability
HAS3 Hyaluronan synthase 3 R =10.8; B =19.2
Hyaluronans are important for the maintenance of a highly hydrated extracellular matrix in tissues and is also involved
in cell adhesion and supports cell migration. It is synthesized by hyaluronan synthases, such as HAS-3
AQP3 Aquaporin 3 R =3.5; B =4.3
Aquaporin 3 is the water/glycerol transporting channel protein expressed in the epidermis which helps maintain the
right level of skin hydration, elasticity and barrier recovery. Both retinol and bakuchiol up-regulated AQP3
Table III Description, fold-change in the DNA microarray experiment and roles of modulated DEJ genes (R: retinol; B: bakuchiol)
Gene Full name Fold-change, function & comments
COL4A6
COL17A1
Collage alpha-6 (IV)
Collagen alpha-1(XVII)
COL4A6: R =6.4; B =11.2
COL17A1: R =3.6; B =8.7
Lamina densa mostly consists of type IV collagen, perlecan and nidogen. Through a complex inter- and intramolecular
interactions type IV collagen forms supra molecular networks that influence cell adhesion, migration, and
differentiation. Type XVII collagen is the protein component of anchoring fibrils that fortifies the attachment of the
epidermis to the dermis.
PLEC1 or
HD1
Plectin I
(Hemidesmosomal
protein 1)
R=2.7; B =6.8
Plectin, a 500-KDa protein and a constituent of the intracellular component of hemidesmosomes, attaches intermediate
filaments to both hemidesmosomes and plasma membranes of basal keratocytes
ITGB4;
ITGB6;
ITGB8;
ITGA6
Integrin beta-4;
Integrin beta-6;
Integrin beta-8;
Integrin alpha-6
ITGB4: R =3.5; B =8.0; ITGB6: R =7.5; B =7.7
ITGB8: R =0; B =3.9; ITGA6: R =0; B =3.6
Integrins are transmembrane glycoproteins and a major component of hemidesmosomes. They mediate the transfer of
information between the extracellular matrix and the interior of the cell, thereby aiding in modulating the organization of
the cytoskeleton, proliferation and differentiation. Main functions: (a) attachment of the cell to the ECM and (b) signal
transduction from ECM to the cell
LAMA3;
LAMC2
Laminin subunit alpha-3
precursor; Laminin
subunit gamma-2
precursor
LAMA3: R =4.7; B =11.0;
LAMC2: R =2.7; B =7.8
Laminins are the major non-collagenous proteins in lamina densa and are integral part of the structural scaffolding in
almost every tissue; Involved in cell differentiation, migration, adhesion as well as phenotype and survival.
CDH1 E-Cadherin R =9.4; B =21.6
One of the most important and ubiquitous types of adhesive interactions required for the maintenance of solid tissues
is that mediated by E-cadherin. E-cadherin has important functions in pluripotency and maintenance of the
differentiated state of cells
©2014 Society of Cosmetic Scientists and the Soci
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International Journal of Cosmetic Science, 1–10
A retinol-like functional compound R. K. Chaudhuri and K. Bojanowski
flattening [46]. Retinol is a well known inhibitor of those processes,
and the finding that bakuchiol has retinol-like functionality at the
ECM and DEJ levels makes it an interesting novel candidate for
anti-ageing applications.
Validation of DNA microarray results by ELISA and histochemistry
Collagens secreted by dermal fibroblasts are major components of
the skin extracellular matrix (type I and type III collagens) and
basement membrane (type IV collagen). In aged and photodamaged
skin, the new collagen pool is decreased due to the inferior amount
and quality of dermal fibroblasts. Therefore, we chose to measure
select collagens by ELISA and histochemistry methods to validate
the data obtained by DNA microarrays. The results, summarized in
the Table IV, confirm the upregulation of types I and IV collagen
in DNA microarray study and also show stimulation of type III
collagen in this mature fibroblast model.
To determine whether the stimulation of type IV collagens in cell
culture translates into a more robust collagen expression in 3D
skin substitute tissue, EpiDermFT tissues were incubated with bak-
uchiol or retinol at 10 lgmL
1
, and histological sections were
stained with anti-type IV collagen antibodies (Fig. 3). The stain
revealed a stronger type IV collagen signal at the dermalepidermal
junction, as compared with the water control, further corroborat-
ing the DNA microarray and ELISA results. This collagen stimula-
tory effect observed in cell culture seems to be due to the selective
metabolic activation of collagen synthesis in fibroblasts, because at
10 lg/mL
1
, bakuchiol or retinol did not enhance cell proliferation
(results not shown).
Water homeostasis of the epidermis is essential for the normal
function of the skin and stratum corneum (SC) hydration. It is a
determinant of skin appearance, mechanical properties, barrier
function and metabolism. In addition, it is indispensable in main-
taining proper water balance of the body. Dehydration of SC is a
typical feature of skin ageing, especially in photo-aged skin and of
Table IV Comparative collagen stimulatory effects of bakuchiol and retinol
as determined by ELISA in human dermal fibroblasts. The stimulatory effect
is expressed as the % of water control (100%)
Test material (10 lgmL
1
) Collagen I Collagen III Collagen IV
Bakuchiol 147 150 119
Retinol 119 148 100
ABC
Figure 3 Effect of Retinol (B) and Bakuchiol (C) on type IV collagen expression compared with non-treat ed control (A) in human EpidermFT (full thickness)
tissue substitutes. Arrows indicate dermo-epidermal juncture (basement membrane), where collagen IV is localized. Note darker band in (B) and (C) as com-
pared to (A) at this level, indicating greater type IV collagen expression.
AC
B
Figure 4 Effect of Retinol (B) and Bakuchiol (C) on aquaporin-3 expression, compared with non-treated control (A) in human EpidermFT (full thickness) tissue
substitutes. Arrows indicate aquaporin-3 staining in the basal layer, where this protein is principally localized.
6©2014 Society of Cosmetic Scientists and the Soci
et
e Franc
ßaise de Cosm
etologie
International Journal of Cosmetic Science, 1–10
A retinol-like functional compound R. K. Chaudhuri and K. Bojanowski
several diseases, for example, eczema, atopic dermatitis, psoriasis
and hereditary ichthyosis (retinol 3.5 fold and bakuchiol 4.3 fold,
Table II) [4750]. To determine whether the increase of the !!!
expression of water channel AQP3 gene observed in DNA micro-
arrays translates into orthotropic increase at the protein level.
EpiDermFT skin substitutes were incubated with retinol, bakuchiol
and compared with the negative (water) control using immunohis-
tochemistry. It was found that both retinol and bakuchiol increased
AQP3 expression (Fig. 4) as visualized by more intense brown col-
oration in retinol and bakuchiol treated tissues located, as
expected, at stratum spinosum and corneum level. Recently, Belle-
mere et al. [51] have shown the effects of all-trans retinoic acid
(ATRA) on AQP3 expression and function both in vitro and ex
vivo. ATRA treatment increased a rapid accumulation of AQP3
transcripts in cultured normal human epidermal keratinocytes.
Also in our model of EpiDermFT skin substitute, both retinol and
bakuchiol increased AQP3 expression.
Clinical study
Taken together, these results prompted us to test bakuchiol clinically.
The formulated product containing 0.5% bakuchiol (no moisturizer
or any other active ingredients or sunscreen included in this formu-
lated product; Table V) was applied twice daily to the whole face.
Sixteen subjects of seventeen enrolled completed the study. One sub-
ject discontinued due to protocol violation. Each of the parameters
was graded on a semi-quantitative scale from 0 to 4 (0, none; 1,
minimal; 2, mild; 3, moderate; and 4, severe). With regard to subjec-
tive evaluation by experts and panelists, the obtained results for the
entire subjects are summarized in Tables VI and VII, respectively.
Evaluations were performed at baseline and then at 4, 8 and
12 weeks and the results compared versus. the baseline.
Retinol is used widely in cosmetic products for reducing the
appearance of the signs of ageing and photo-damage [52]. Retinol
is a precursor of retinoic acid. Once it penetrates skin, it is sequen-
tially oxidized to retinoic acid, causing retinoic acid-like effects, but
is notably less irritating. Currently, most of these products contain
0.1% or lower of retinol. However, even at this low concentration,
some irritation can occur [53]. It seems that bakuchiol has accept-
able skin tolerability.
Analysing the data (Table VI vs. Table VII), it is evident that %
improvement score for roughness & dryness and radiance given by
expert is significantly higher versus. the panelists’ self-evaluation. It
is interesting to note that % improvement score given by the sub-
jects, on the other hand, for fine lines and wrinkles and eye area
appearance is significantly higher than the score given by the
expert. Most of the parameters were improved significantly more
after 8 weeks compared to 4 weeks of application of bakuchiol,
showing a certain degree of cumulative beneficial effect over time.
Results obtained from silicone replica analysis using profilometry
are summarized in Table VIII. Comparison of results of day 0 (base
line) vs. 4, 8 and 12 weeks treated skin provided 7%, 13% and
20% reduction in wrinkle depth (Ry), respectively. All three
results are statistically significant (P0.01). Comparison of results
of day 0 (baseline) versus. 4, 8 and 12 weeks treated skin yielded
Table V Formulation details of bakuchiol
Ingredient Trade name/supplier % w/w
Phase A
Glyceryl stearate
and PEG-100
Arlacel 165/Uniqema 1.50
Arachidyl alcohol,
Behenyl alcohol,
Arachidyl glucoside
Montanov 202/Seppic 4.00
Dimethyl isosorbide Arlasolve DMI/Uniqema 3.00
Isohexadecane Permethyl 101A/Presperse 8.00
Dimethicone Dow Corning 200, 100 cst/Dow Corning 2.00
Bakuchiol Sytenol A/Sytheon 0.50
Phase B
Water 69.75
Propylene Glycol Propylene glycol/Lyondell 2.00
Pentylene Glycol Hydrolite-5/Symrise 3.00
Xanthan Gum Vanzan NF/Vanderbilt 0.25
Phase C
Dicaprylylether Cetiol OE/Cognis 4.00
Hydroxyethylacrylate
(and) sodium
acryloyldimethyl
taurate copolymer
Sepinove EMT 10/Seppic 1.00
Phenoxyethanol
(and) Caprylyl glycol
Optiphen or Microcare PHG 1.00
Total 100.00
Table VI Subjective evaluation by expert % improvement vs. baseline
Parameters 4 Weeks 8 Weeks 12 Weeks
Roughness & dryness 65 81 90
Fine lines/wrinkles 5 16 29
Skin tone 14 29 39
Skin elasticity/firmness 13 20 39
Radiance 24 40 52
Skin brightening 13 35 46
Eye area appearance 8 24 46
Table VII Subjective evaluation by panelists % improvement vs. baseline
Parameters 4 Weeks 8 Weeks 12 Weeks
Roughness & dryness 35 40 48
Fine lines/wrinkles 19 25 23
Skin tone 12 19 29
Skin elasticity/firmness 14 23 25
Radiance 11 17 30
Skin brightening 10 14 29
Eye area appearance 22 24 35
Table VIII Silicone replica analysis using profilometry: % reduction vs.
baseline
Parameters 4 Weeks 8 Weeks 12 Weeks
Wrinkle depth 7% 13% 20%
Skin roughness 2% 10% 21%
©2014 Society of Cosmetic Scientists and the Soci
et
e Franc
ßaise de Cosm
etologie 7
International Journal of Cosmetic Science, 1–10
A retinol-like functional compound R. K. Chaudhuri and K. Bojanowski
2%, 10% and 21% reduction in skin roughness (Ra), respec-
tively. The results at 8 and 12 weeks are statistically significant
(P0.004).
The photos (Fig. 5; before and after treatment) shown here are
representative of the results that have been obtained with bakuchi-
ol treatment for 12 weeks.
Clinical grading and comparative analysis of skin profilometric
measurements were performed at baseline and after 4, 8 and
12 weeks of application. After 8 weeks of daily application, a
significant reduction in the wrinkle depth and roughness was
observed with the product vs. baseline. These changes were even
greater after 12 weeks of product application. For example, wrinkle
depth reduction (Fig. 5C) is significantly more after 8 weeks com-
pared to 4 weeks of application of bakuchiol (subject no. M572)
showing a certain degree of cumulative beneficial effect over time.
The significant improvement in fine lines and wrinkles, elasticity,
firmness and overall reduction in signs of photodamage including
even toning effects observed after 12 weeks of treatment provided
the ultimate validation of the in vitro results and were in line with
the retinoid-type functionality of bakuchiol.
Conclusion
Given the fact that retinol and bakuchiol do not have close struc-
tural similarities, yet they exhibit a similar gene expression profile,
especially on certain key anti-ageing genes and proteins,which is
remarkable. Bakuchiol has several substantial advantages over reti-
nol, including excellent photochemical and hydrolytic stability a
good safety profile and ease to formulate due to miscibility with a
wide variety of emollients and solubilizers [18]. Bakuchiol can be
used during the day due its photostability. Interestingly, bakuchiol
is an excellent stabilizer of retinol under photo-oxidative as well as
singlet oxygen environments (not discussed here). This property
may help reduce oxidative stress caused by retinol when combined
with bakuchiol and used at concentrations higher than the physio-
logical limit [54].
This open clinical pilot study needs further confirmation of bak-
uchiol bioactivity in vivo, from vehicle- or benchmark-controlled
studies. The similarity of gene expression and protein synthesis
stimulation observed in the comparison of bakuchiol with retinol
is, however, remarkable and suggests that similar bioactivity in vivo
is probable. Taken together, this study demonstrates the potential
of bakuchiol, a true retinol-like functional compound, to become a
key ingredient for dermatological and skin care products.
Acknowledgements
The authors would like to thank Sytheon Ltd for funding this
research and to Stephanie Ma for her dedicated assistance in this
project.
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ßaise de Cosm
etologie
International Journal of Cosmetic Science, 1–10
A retinol-like functional compound R. K. Chaudhuri and K. Bojanowski
... Zur Prüfung der Anti-Aging-Effekte von Bakuchiol wurden verschiedene In-vitro-Studien durchgeführt [87]. Dabei stand die Frage im Mittelpunkt, ob Bakuchiol als photochemisch stabile und galenisch relativ leicht in Topika zu verarbeitende Substanz eine mögliche Alternative zu den Retinoiden -und hier speziell zu Retinol -ist. ...
... Dabei stand die Frage im Mittelpunkt, ob Bakuchiol als photochemisch stabile und galenisch relativ leicht in Topika zu verarbeitende Substanz eine mögliche Alternative zu den Retinoiden -und hier speziell zu Retinol -ist. Neben vergleichenden Genexpressionsanalysen in einem Vollhautmodell wurden im direkten Vergleich die Expression von Typ I-, Typ-III-und Typ-IV-Kollagen sowie von Aquaporin-3 mittels ELISA und/oder histochemischer Untersuchung in menschlichen dermalen Fibroblasten und in Hautersatzmodellen analysiert [87]. ...
... Diese Ähnlichkeit wurde sowohl durch den Seite-an-Seite-Vergleich in der Modulation einzelner Gene als auch auf der Proteinebene bestätigt. Des Weiteren wurden für Bakuchiol mit Retinol vergleichbare Effekte bei der Hochregulation von Kollagen Typ I und Typ IV mittels DNA-Microarray sowie bei der Stimulation von Kollagen Typ III im reifen Fibroblasten-Modell gefunden [87]. ...
Article
Falten reduzieren, die Haut straff halten und einen frischen Teint herbeizaubern — diese Versprechungen machen Cosmeceuticals. Sie enthalten meist effektivere Inhaltsstoffe als herkömmliche Kosmetika.
... Retinoids are a group of chemical compounds that inhibit cell division during excessive proliferation and activate it when the process is too slow. They play an active role in protein production, cellular metabolism and cell division [28,34,37]. Retinoids also affect the thickness and color of the skin, regulate the function of the sebaceous glands, and limit sebum production, as well as being responsible for hair and nail growth, and also influencing the distribution of melanin in the skin [27,30,35]. ...
... Chaudhuri and Bojanowski showed that bakuchiol can prevent wrinkles; improve pigmentation, elasticity and firmness; and reduce overall photodamage. The authors stress that this compound can be used as a retinol-like anti-ageing functional compound [37]. ...
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Human skin is continually changing. The condition of the skin largely depends on the individual’s overall state of health. A balanced diet plays an important role in the proper functioning of the human body, including the skin. The present study draws attention to bioactive substances, i.e., vitamins, minerals, fatty acids, polyphenols, and carotenoids, with a particular focus on their effects on the condition of the skin. The aim of the study was to review the literature on the effects of bioactive substances on skin parameters such as elasticity, firmness, wrinkles, senile dryness, hydration and color, and to define their role in the process of skin ageing.
... Even though the molecular structure is dissimilar, in vitro experiments suggest that it induces a pattern of gene expression in a skin cell line that has many similarities with retinol and has thus been proposed as a functional analogue of retinol. 51 Bakuchiol also exhibits antioxidant and anti-bacterial activity. 52 A small, singleblinded clinical study accompanying the in vitro investigation reported that topical bakuchiol at a concentration of 0.5% applied twice daily resulted in improvements in skin aging parameters at 4, 8 and 12 weeks. ...
... There was no control arm and the study was performed by Syntheon Ltd, a company specializing in bakuchiol-based cosmeceuticals. 51 Independent clinical trial data is needed before any conclusions may be drawn about the suitability of bakuchiol in skin rejuvenation. ...
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Background Aesthetic practice relies on a harmonious relationship between medicine and commerce. Bridging the gap are a large number of skincare products that make therapeutic claims while avoiding the regulatory framework of pharmaceuticals. In this grey area we find ourselves poorly disposed to counsel our patients wisely as the industry is expanding faster than empirical evidence of efficacy and safety can be acquired. To serve our patients and engage with industry we must understand the theoretical principles and evaluate the clinical evidence in practice. Objectives The purpose of this paper is to classify cosmeceuticals by method of action, explain how they work in principle with reference to skin aging and evaluate the clinical evidence for them. Methods A literature and cosmetic clinic website search was conducted to establish a list of the most commonly advertised cosmeceuticals and a peer-reviewed literature search was then conducted to establish the clinical evidence for them. Results A huge number of cosmeceuticals are marketed for skin rejuvenation but almost invariably they fall into one of four categories. These include the induction of tissue repair mechanisms, inflammatory modulation, scavenging of reactive oxygen species or a combination of the three. With the exception of retinol derivatives and hydroxyl acids the clinical evidence is limited, despite promising preclinical evidence for several cosmeceuticals. Conclusions Cosmeceuticals reside within a highly competitive ecosystem and are often brought to market based on preclinical, not clinical evidence. Success and failure will largely be governed by the establishment of clinical evidence in retrospect.
... Bakuchiol (BK), a plant-based retinol-like alternative to retinol, has been shown to regulate the expression of genes and proteins involved in the skinaging process, and it significantly improves lines and wrinkles, pigmentation, elasticity, firmness and overall reduction in photo-damage without the undesirable effects usually associated with retinol therapy. 19,20 Vanilla tahitensis extract (VTE) also possesses numerous medicinal properties such as antioxidant power and they are rich in polyphenols that are well known to improve the signs of skin aging. 21 Therefore, the aim of the current study was to evaluate the anti-aging effects of a new combination of two active ingredients, BK and VTE, in in vitro and ex vivo studies and in a clinical study in women with naturally aged skin. ...
... Bakuchiol (BK; Sytenol ® , Sytheon Ltd) was purchased from Rahn France and was obtained from Psoralea coryfolia with a purity of about 95%. 19 BK was used in cell culture at 0.5 µg/mL from a 10 mg/mL stock solution in dimethylsulfoxide. Vanilla tahitensis extract (VTE; Vanirea ® ) was obtained from Solabia Ltd France. ...
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Background: Skin aging is characterized by slacking and loss of density, especially under ultraviolet (UV) radiation exposure. Objective: To investigate the beneficial effects of a combination containing bakuchiol (BK) and vanilla tahitensis extract (VTE) to prevent skin photoaging in vitro and to improve clinical outcomes for naturally aged skin. Materials and methods: Human dermal fibroblasts were treated with active compounds, exposed to an acute dose of UVA and analyzed by confocal microscopy: actin network for morphology, interleukin-8 (IL-8) for inflammation and p16 for senescence. Human skin was used to evaluate chronic UVA-induced glycosaminoglycan (GAG) loss and to assess the benefit of topical application of a BK+VTE serum (Alcian blue staining). An open-label clinical trial was conducted in women applying the serum twice daily for 56 days (n=43). Skin remodeling was assessed by FaceScan®. Firmness was evaluated through Dynaskin® and clinical scoring. Skin radiance was also rated on standardized full-face photographs. Results: UVA induced a significant increase in IL-8 and p16 expression and marked morphological changes in fibroblasts. Treatment with BK or VTE alone prevented both actin network alteration and IL-8 upregulation. Interestingly, BK+VTE demonstrated synergistic protection against IL-8 and p16 overexpression. Serum application prevented GAG loss at the dermo-epidermal junction and increased dermal GAG in UVA-exposed skin explants. In the clinical trial, face ptosis was reduced by 11% on average for 26 responsive subjects and up to 23%. Depth of skin deformation was also reduced by 24% on average for 30 responsive subjects and up to 30%. This firming effect was confirmed by clinical scoring. Radiance was significantly improved by 29% on average for 33 responsive subjects. The serum demonstrated good tolerance/safety. Conclusion: BK+VTE combination demonstrated anti-aging efficacy and might provide a substantial benefit in the daily care of naturally aged skin in women, through their synergistic effect on inflammaging and senescence.
... An increase in the development of cosmetic products has followed the rising demand for naturally derived and effective skin ingredients. 7 Two examples include bakuchiol derived from the plant Psoralea corylifolia with its retinol-like properties 2,8 and kojic acid derived from the fungus Rhizomucor miehei with its anti-tyrosinase properties. 9 Both of these cosmeceutical ingredients also function as antioxidants and are increasingly being used in cosmetic products on the market. ...
... 9 Both of these cosmeceutical ingredients also function as antioxidants and are increasingly being used in cosmetic products on the market. 2,9 An emerging concern with cosmeceuticals is their potential influence on the skin microbiome as seen with antibacterial soaps. [10][11][12] In some cases, such as triclosan, there may be an influence on the infant microbiome. ...
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Objective Acetyl zingerone (AZ), a derivative of the phytochemical zingerone from Zingiber officinale (ginger), is a novel compound that is purported to have anti‐aging properties. The objective of this clinical study was to assess the role of acetyl zingerone in its ability to improve the appearance of facial skin wrinkles, redness, pigmentation, and photoaging was assessed. Methods Thirty‐one healthy participants (age 44 ± 7 years) were randomized in blinded fashion to apply either 1% AZ or placebo, consisting of the vehicle base cream, to the full face twice daily for 8 weeks with a total of 3 visits. Signs of photoaging, including wrinkles, dyspigmentation, and redness were assessed with facial image analysis photography and software. Results There was a significant decrease in average wrinkle severity (p=0.019; Mean=‐25.7% change), total wrinkle volume (p=0.003; Mean=‐30.1 % change), pigment intensity (p=0.021; Mean=‐25.6% change), and redness intensity (p=0.035; Mean=‐20.7% change) in the AZ group by 8 weeks compared to the placebo. No significant itching, burning, or stinging was noted by study participants. There was also no significant difference between both groups in the clinical assessment of scaling, erythema, hypopigmentation, or hyperpigmentation. Conclusions and Relevance Topical AZ improves photodamage and decreases the appearance of wrinkles, dyspigmentation, and redness intensity when compared to placebo (vehicle) formulation. Acetyl zingerone is well tolerated with daily use.
... Melatonin (5acetyl-5-methoxytryptamine) is a pineal hormone that acts as both an indirect antioxidant, by inducing antioxidative gene expression, and a free radical scavenger [13,14]. Bakuchiol (4-[(1E,3S)-3-ethenyl-3,7-dimethyl-1,6-octadien-1yl]phenol) is a naturally occurring phenolic compound with retinol-like properties [15]. Bakuchiol induces collagen expression in cultured fibroblasts and activates the expression of genes involved in antioxidant defense [15,16]. ...
... Bakuchiol (4-[(1E,3S)-3-ethenyl-3,7-dimethyl-1,6-octadien-1yl]phenol) is a naturally occurring phenolic compound with retinol-like properties [15]. Bakuchiol induces collagen expression in cultured fibroblasts and activates the expression of genes involved in antioxidant defense [15,16]. Bakuchiol is also thought to act as a direct free radical scavenger [17]. ...
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Introduction: Photoaging is a complex process that is chiefly the result of oxidative stress caused by ultraviolet (UV)-generated reactive oxygen species. To counter this process, we developed a 3-in-1 night facial serum (3-in-1 NFS) containing a combination of direct and indirect antioxidants and polyphenols that is designed to attenuate UV-generated free radicals and stimulate dermal protein synthesis. In clinical trials 3-in-1 NFS improved the appearance of photoaged skin. In this study we sought to identify some of the main histologic changes responsible for this. Methods: We performed an immunolabeling analysis of some of the salient epidermal and dermal proteins in 3-in-1 NFS-treated primary epidermal keratinocytes (HEKs) and dermal fibroblasts (HDFs) in vitro, and in UV-exposed skin explants ex vivo. Numbers of apoptotic sunburn cells following exposure of 3-in-1 NFS-treated skin explants to UV radiation were also determined. Results: We demonstrate that 3-in-1 NFS increases levels of filaggrin and aquaporin 3 in HEKs, and levels of collagen I and collagen III in HDFs in vitro. Levels of precursor procollagen type I and tropoelastin were increased in ex vivo skin explants. Numbers of apoptotic sunburn cells were significantly reduced in UV-exposed skin explants. These effects were only observed with the combination of ingredients in 3-in-1 NFS, suggesting that they have a synergistic effect on photoaged skin biology. Conclusion: Our results show that some of the histological hallmarks of photoaging are improved with the use of 3-in-1 NFS.
... The metabolites and crude extracts derived from herbs and plants are important in the search for new antifungal agents. 13 Bakuchiol has been widely used for skincare regimens, as anti-wrinkle and anti-aging agent 13 and has previously been linked with antimicrobial properties. 14 It has been reported that garlic extract (Allium sativum) can inhibit growth of both Gram-positive and Gram-negative bacteria. ...
... The metabolites and crude extracts derived from herbs and plants are important in the search for new antifungal agents. 13 Bakuchiol has been widely used for skincare regimens, as anti-wrinkle and anti-aging agent 13 and has previously been linked with antimicrobial properties. 14 It has been reported that garlic extract (Allium sativum) can inhibit growth of both Gram-positive and Gram-negative bacteria. ...
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Objective: Chlorhexidine mouthrinses are considered a gold standard as an adjunct treatment of oral infections. However, owing to its toxicity, discoloration of tooth surface and the emerging prevalence of drug-resistant species, attention is being given to exploring natural alternatives to the drug. Methods: The experiment was carried out in Azra Naheed Center for Research and Development (ANCRD), Superior University, Lahore, Pakistan from September 2018 till May 2019. Biofilms and planktonic cells of C. albicans alone and in combination with streptococci were subjected to chlorhexidine, allium sativum and bakuchiol individually and to allium-bakuchiol combination. Kirby-Bauer test, antifungal susceptibility testing, CFU count and drug synergy assessment was done on planktonic cells. Dynamic biofilms were formed to mimic conditions similar to oral cavity and CFU was determined. Results: MIC of all three agents was higher against mixed species when compared to single species planktonic cells and biofilm. Allium sativum and bakuchiol demonstrated synergistic effects. The decrease in CFU count and minimum biofilm reduction to salivary pellicle caused by allium sativum-bakuchiol was comparable to that of chlorhexidine. Conclusion: Thus, allium sativum-bakuchiol combination demonstrated antimicrobial effects similar to chlorhexidine against planktonic cells and dynamic biofilm. It could serve as a possible natural, economical alternative to chlorhexidine mouthrinses usually recommended in dental clinics. However, in vivo studies are required to determine the correct dosage of these agents.
... Bakuchiol is a functional analog of retinol and has shown many physiological properties; its first commercial use in topical applications was introduced to the market under the trade name Sytenol® A by Sytheon Ltd. (Boonton, NJ, USA) in 2007 [53]. The important physiological and biological properties of bakuchiol include its applications as (1) preventative and restorative antiaging; (2) anti-acne; and (3) skin lightening/even toning products; many products are available in the market [54][55][56]. ...
Article
A sensitive and reliable high–performance thin–layer chromatography method has been developed for the simultaneous estimation of bavachin, bakuchiol, and psoralen in Psoralea corylifolia seeds. The methanolic extract of the seeds was applied on a silica gel G 60 F254 plate. The plate was developed using toluene–ether, 1:1, saturated with 10% acetic acid (v/v) as the mobile phase and detection and quantification were performed by densitometric scanning at 254 nm. The correlation coefficients were found to be 0.999, 0.999, and 0.999 for bavachin, bakuchiol, and psoralen, respectively, in the developed method. The accuracy of the method was confirmed by conducting recovery studies at different levels using the standard addition method. The average recovery of bavachin, bakuchiol, and psoralen was found to be close to 98% confirming the accurateness of the method. The proposed method offers a new, sensitive, specific, and precise gauge for quantification of bavachin, bakuchiol, and psoralen representing all the categories of bioactive constituents in P. corylifolia.
... It was initially identified in Otholobium pubescens, a kind of Peruvian medicinal plant used for the treatment of diabetes (Krenisky et al., 1999). Recently, Bak has been demonstrated to have numerous pharmacological properties, including the antioxidative and anti-inflammatory, antidiabetic, antiaging, and anticancer properties Seo et al., 2013;Chaudhuri and Bojanowski, 2014;Lim et al., 2019;Xin et al., 2019). For example, Bak maintains the activities of mitochondrial respiratory enzyme and protects the functions of mitochondrial against oxidative stress injury (Haraguchi et al., 2000). ...
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Subarachnoid hemorrhage (SAH) is a fatal cerebrovascular condition with complex pathophysiology that reduces brain perfusion and causes cerebral functional impairments. An increasing number of studies indicate that early brain injury (EBI), which occurs within the first 72 h of SAH, plays a crucial role in the poor prognosis of SAH. Bakuchiol (Bak) has been demonstrated to have multiorgan protective effects owing to its antioxidative and anti-inflammatory properties. The present study was designed to investigate the effects of Bak on EBI after SAH and its underlying mechanisms. In this study, 428 adult male C57BL/6J mice weighing 20 to 25 g were observed to investigate the effects of Bak administration in an SAH animal model. The neurological function and brain edema were assessed. Content of MDA/3-NT/8-OHdG/superoxide anion and the activity of SOD and GSH-Px were tested. The function of the blood-brain barrier (BBB) and the protein levels of claudin-5, occludin, zonula occludens-1, and matrix metalloproteinase-9 were observed. TUNEL staining and Fluoro-Jade C staining were conducted to evaluate the death of neurons. Ultrastructural changes of the neurons were observed under the transmission electron microscope. Finally, the roles of Trx, TXNIP, and AMPK in the protective effect of Bak were investigated. The data showed that Bak administration 1) increased the survival rate and alleviated neurological functional deficits; 2) alleviated BBB disruption and brain edema; 3) attenuated oxidative stress by reducing reactive oxygen species, MDA, 3-NT, 8-OHdG, gp91phox, and 4-HNE; increased the activities of SOD and GSH-Px; and alleviated the damage to the ultrastructure of mitochondria; 4) inhibited cellular apoptosis by regulating the protein levels of Bcl-2, Bax, and cleaved caspase-3; and 5) upregulated the protein levels of Trx1 as well as the phosphorylation of AMPK and downregulated the protein levels of TXNIP. Moreover, the protective effects of Bak were partially reversed by PX-12 and compound C. To summarize, Bak attenuates EBI after SAH by alleviating BBB disruption, oxidative stress, and apoptosis via regulating Trx1/TXNIP expression and the phosphorylation of AMPK. Its powerful protective effects might make Bak a promising novel drug for the treatment of EBI after SAH.
Article
Background: Changes induced by intrinsic and extrinsic photoaging result in signs of skin aging including altered pigmentation and wrinkles. A 3-in-1 night facial serum (NFS) was developed to treat skin aging by antioxidative and retinoid-like mechanisms. Objective: To determine the clinical and histological effects of the 3-in-1 NFS on signs of skin aging, clinically and histologically. Methods & materials: Twenty-four subjects applied serum nightly for 12 weeks, and 12 subjects continued an extension study to 24 weeks. Clinical assessment of skin quality was performed by dermatologists. Skin biopsy was performed at 12 weeks to assess histological changes. Results: There was a global aesthetic improvement over the duration of the study: +1.21 points at 12 weeks; +1.25 at 24 weeks. Skin texture, pigmentation, erythema, skin tone, complexion, lines, and wrinkles all significantly improved (P < .05). There was also a significant reduction in photodamage, hyperpigmentation, and wrinkle scores, most notably horizontal forehead expression lines, and marionette lines (P < .05 for all). Dermal and epidermal thickness increased without reaching statistical significance. Conclusion: The 3-in-1 NFS had clinically and statistically significant effects on signs of skin aging after 12 weeks, which became more pronounced after 24 weeks.
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Vitamin A is involved in the biosynthesis of the visual pigment rhodopsin (1), in embryogenesis (2), as well as in cell growth and differentiation (3). It exists in interconvertible forms as retinol, its esters (the main storage form in the body) and retinaldehyde, whereas the latter is irreversibly converted to retinoic acid, the biologically active form of vitamin A that binds to nuclear receptors and modulate gene expression (Fig. 1) (4,5). Retinoic acid exists as three cis/trans isomers: all-trans-, 9-cis- and 13-cis- retinoic acid; all-trans-retinoic acid (retinoic acid, tretinoin) binds to the nuclear receptors such as retinoic acid receptor (RAR)-α, β, and γ with a high affinity, 9-cis-retinoic acid (alitretinoin) binds to RAR-α, β, γ and retinoid X receptor (RXR)-α, β, γ with a high affinity, whereas 13-cis-retinoic (isotretinoin) does not bind to nuclear retinoid receptors with significant affinity (6,7).
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KEY WORDS: acne, bakuchiol, antioxidant, anti-inflammatory, antibacterial, matrix metalloprotease ABSTRACT: Bakuchiol, a meroterpene of plant origin, is shown here to act against four major pathophysiologic features that cause acne, suggesting its use to complement and/or enhance the effectiveness of current anti-acne agents. In addition, the material is non-irritating, presents no photo-or hydrolytic-stability issues and is easy to use.
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OBJECTIVE: To study the nephrotoxicity induced by bakuchiol alone and bakuchiol combined with psoralen and to explore its mechanism. METHODS: The cytotoxicities of bakuchiol and bakuchiol combined with psoralen were investigated using human renal tubular epithelial cell lines (HK-2) , in presence or absence of hepatic S9 mixture. The HK-2 cells were exposed culture medium alone (blank control), 0.5% DMSO (vehicle control), aristolochic acid I (AA I; positive control) , psoralen 5 μ-L-1 group, bakuchiol 5, 10, 20, 30 and 40 μ-L-1 groups, and bakuchiol + psoralen (20+5) , (30+5) and (40+5) μmol·L-1 groups, respectively. The cell viabilities were examined by MTT assay; cell membrane injuries were examined by detecting lactate dehydrogenase ( LDH ) release rate ; and the morphological changes in HK-2 cells were observed with contrast microscope. The rate of cell apoptosis was detected by Annexin V/PI staining, and cell cycle was detected by PI staining with flow cytometry. RESULTS: No cytotoxicity was found in psoralen 5 μmol·L-1 group. The HK-2 cell viabilities were significantly reduced after 4, 24, 48 and 72 h of exposure to either bakuchiol 20, 30 and 40 μmol·L-1 groups or bakuchiol + psoralen (20+5), (30+5) and (40+5) μmol·L-1 groups in a time- and concentration-dependent manner. The IC50 values of bakuchiol were (26.4±4.8), (21.8±0.6) and (24.1±0.8)μmol·L -1 for 24, 48 and 72 h exposure, respectively. The cytotoxicity of bakuchiol was significantly decreased in presence of hepatic S9 mixture. The LDH release rate of HK-2 cell increased significantly after 24 h of exposure to bakuchiol 20, 30 and 40 μmol·L-1 or bakuchiol + psoralen groups. With the concentration and time increasing, the HK-2 cells became more and more contracted and rounded. In bakuchiol 40 μmol·L-1 or bakuchiol + psoralen (20+5), (30+5) and (40+5) μmol·L-1 groups, HK-2 cells showed apoptotic characters. In bakuchiol or bakuchiol + psoralen groups, apoptotic cells significantly increased and cells in G 2 phase markedly decreased. CONCLUSION: Bakuchiol has a significant cytotoxicity in HK-2 cells, and combined with psoralen can not decrease its toxicity. The cytotoxicity of bakuchiol is significantly reduced in the presence of hepatic S9 mixture. The possible mechanisms of the renal cytorotoxicity of bakuchiol are as follows: Circle digit 1 direct damage to the cell membrane; Circle digit 2 inducing cell apoptosis; Circle digit 3 inhibiting intracellular DNA synthesis and block cell mitosis and proliferation.
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Retinol is an ingredient used in cosmetic products for reducing the appearance of the signs of aging and photo-damage. Currently, most of these products contain 0.1% of retinol. However, at this concentration, some irritation can occur. We have evaluated in vitro and in a clinical study the potential efficacy of a combination of actives to improve the facial skin aging signs while using low concentration of retinol. We demonstrated, in vitro, that a chromone derivative, 5,7-di-hydroxy-2-methyl chromone (DMC), is able to enhance the collagen synthesis in culture of normal human dermal fibroblasts. The enhancement of retinol anti-wrinkle efficacy by DMC was confirmed in a small scale clinical trial. Specifically, a product associating low concentration of retinol (0.04%) and DMC (0.1%) in combination with low mo-lecular weight hyaluronic acid fragments (50,000 Dalton of average molecular weight) has been applied topically for 8 weeks. Clinical results show significant improvement of various signs of facial skin aging such as wrinkles, pigmentary spots, tone unevenness, dullness and the overall photo-damage score. Improvements were still visible 4 weeks after the cessation of the test product application. This study demonstrates that significant lasting improvement of facial skin aging can be obtained with well tolerated low concentration of retinol when adequately formulated with other anti-aging ingredients.
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Article
Bakuchiol, a terpene phenol from Psoralea corylifolia Linn has only one asymmetric centre. By suitable correlation with (+)-linalool on the one hand and, with (+)-3-methyl-3-methoxy-carbonyl-n-valeria acid on the other, it has been shown to possess (S)-chirality.
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Isolation and structure elucidation of a novel monoterpene phenol, bakuchiol, from the seeds of Psoralea corylifolia Linn, is described.