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Bakuchiol in the management of acne-affected Skin

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Bakuchiol in the management of acne-affected Skin

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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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Bakuchiol in the Management
of Acne-affected Skin
Ratan K. Chaudhuri, PhD
Sytheon Ltd., Boonton, NJ, USA
Francois Marchio
Sytheon SARL, Carros, France
KEY WORDS: acne, bakuchiol, antioxidant, anti-inflammatory,
antibacterial, matrix metalloprotease
ABSTR ACT: 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.
Acne vulgaris is a common, chronic
and recurring disease that involves
multiple etiological factors including
follicular hyperkeratinization, increased
sebum production, Propionibacterium
acnes proliferation and inammation.1
It aects about 80% of teenagers and
young adults and is most prevalent in
those aged 12 to 24 years, although it can
occur at all ages. As many as 17 million
people are thought to be aected in
the United States alone and the acne
therapeutics market is forecast to show
moderate growth in revenues through
2016; market data suggests the global
acne market was worth US $2.8 billion
in 2009 and is estimated to reach
revenues of $3.02 billion by 2016.2 is
moderate increase in revenue is attrib-
uted to an overcrowding of the market
with generics and increased consumer
acceptance of alternative therapies,
although the acne therapeutics market
is witnessing a shi toward combination
products using two or more eective
acne treatments.
One of the major causes of acne is
the increase in sex hormones, especially
androgens such as testosterone, which
occurs during puberty.3 Testerone is
converted in the skin to dihydrotestos-
terone (DHT) by α-reductase, which
stimulates the sebaceous glands to
enlarge and produce more sebum. e
more sebum produced, the worse the
acne will become. Further, a study by
Lee et al. suggests that DHT may also
be involved in the production of proin-
ammatory cytokines in acne.3
Abnormal follicular keratinization
is also involved in the development
of acne vulgaris. The presence of
unsaturated fatty acids in sebum alter
the calcium dynamics in epidermal
keratinocytes and induce abnormal fol-
licular keratinization,4 and if sebum and
keratin block the skin pores, they can
cause comedones—small, skin-colored
bumps or papules—to develop and hair
follicle walls to rupture. Further, bacte-
rial and comedonal debris cause acne
pimples or pustules, i.e., inammatory
lesions.
Acne typically appears on the oil-
producing areas of the body, namely the
face, chest and back, and can have short-
term, potentially lasting psychological
eects such as decreased self-esteem
and self-condence leading to social
withdrawal and even depression. While
the three levels of acne severity are
generally considered mild, moderate or
severe, even mild acne can be trouble-
some, especially to teenagers who
see each pimple as a major cosmetic
challenge.
Interestingly, using a genetic-based
strategy, Bek-omsen et al. recently
demonstrated that follicles from healthy
skin were exclusively colonized by
P. acnes, whereas the follicular micro-
biota of acne patients included, in
addition to P. acnes, Staphylococcus
epidermidis and minor proportions
of other species.5 However, previous
studies excluded Staphylococci as agents
that play a role in the pathogenesis of
acne due to their rapid development of
resistance to therapeutic antibiotics.6
e presence of S. epidermidis exclu-
sively in acne-aected follicles raises
the question of the potential role of this
species in acne.
Treating Acne
ere are four major targets presently
governing acne therapy, including cor-
recting the altered pattern of follicular
keratinization; decreasing sebaceous
gland activity; decreasing the follicular
bacterial population, especially P. acnes;
and producing an anti-inammatory
effect by inhibiting the production
of extracellular inflammatory prod-
ucts through the inhibition of these
Bakuchiol shows promise
as a new agent that can
complement and enhance
the effectiveness
of currently available
anti-acne formulations.
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microorganisms.7 ese mechanisms
are described in more detail in the
Discussion and Results section later in
this article.
Presently, oral or topical isotretinoin
(retinoic acid) is the only single agent
that is eective against all four major
pathophysiologic features. However,
when used at therapeutic doses, this
drug is responsible for several serious
side eects including teratogenicity8 due
to interference of the exogenous retinoic
acid with endogenous retinoic acid
signaling, which plays a role in the pat-
terning of developing embryos.9 Further,
the use of broad-spectrum antibiotics
such as er ythromycin, clindamycin,
etc., has led to widespread resistance.
erefore, retinoic acid should be used
only in the most severe cases and alter-
native treatment approaches should be
considered rst.
The mos t co mmon al tern ate
approaches include exfoliating agents
such as salicylic and glycolic acid
but skin becomes more sensitive to
sun-induced damage when exfoliating
agents are used for long periods of
time. Another common agent found in
anti-acne products in the United States
is benzoyl peroxide. It was previously
listed as a Category III ingredient,
meaning its safety was uncertain, but in
2010 it was reclassied as a Category I
ingredient, meaning it is generally
recognized as safe and eective. e
recommendation now is that acne treat-
ments be combined to target as many
pathogenic factors as possible.10, 11
Bakuchiol and Acne
Meroterpene, especially bakuchiol
(see Figure 1), has been reported to
exhibit strong antibacterial eects.12, 13 In
relation, a comparative DNA microarray
study using bakuchiol and retinol, and
bakuchiol’s anti-aging potential were
recently reported by Chaudhuri.14, 15
Interestingly, the authors reported that
Tazarotene-inducible gene 1 (TIG1) is
signicantly up-regulated by both baku-
chiol and retinol, and the expression of
TIG1 is found to be down-regulated
in a variety of human cancers as well
as acne, rosacea and psoriasis. us, it
is quite conceivable to assume that the
up-regulation of TIG1 gene by bakuchiol
may provide a solution to problem skin.
This led the authors to further
examine that mate rial’s anti-acne
activity in the described study, where a
specic natural 95% pure meroterpene
obtained from the edible seeds of
Psoralea corylifoliaa, 4-[1E, 3S)-3-
ethenyl-3, 7-dimethyl-1, 6-octadienyl
(INCI: Bakuchiol) was evaluated to
determine if it could eectively treat
acne-affected skin.16, 17 In addition,
the authors sought to determine if
bakuchiol could be used in combina-
tion with salicylic acid. Assessments
were made by evaluating the material’s
effects on 5-α-reductase expression,
antibacterial and antifungal inhibition,
collagenase and elastase inhibition, and
inammation. Its clinical ecacy also
was evaluated.
Materials and Methods
5-α-reductase expression: HaCaT
human kerationocytes were used to
study the effects of bakuchiol and
retinoic acid on 5-α-reductase expres-
sion. Both materials were diluted in test
concentrations ranging from 5 to 50 µg/
mL in the culture media. At conuence,
cells were trypsinized and seeded in
microplates at a density of 50,000 cells
per well. Aer a 4-hr incubation, the
supernatants were discarded and new
culture medium was added contain-
ing the test and control products, i.e.,
without bakuchiol or retinoic acid.
Aer 48 hr of incubation at 37°C in an
atmosphere containing 5% CO2, the
supernatants were discarded and the
cells were washed using sterile PBS. e
expression of 5-α-reductase was then
measured via an immunouorescence
technique using a specic antibody and
evaluated spectrofluorometricallyb at
excitation wavelengths of 485 nm and
emission wavelengths of 530 nm.
Antibacterial and antifungal inhibi-
tion: To assess the antibacterial and
antifungal activity of bakuchiol and
salicylic acid, their inhibitory concen-
trations (IC50) against P. acnes rst were
dened as the points at which turbidity
was limited to < 0.02 atomic units (AU)
at 610 nm. e IC50 values (in µg/mL)
were established to be 0.6 µg/mL for
bakuchiol and 27 µg/mL for salicylic
acid.
Collagenase inhibitory activity:
e impact of bakuchiol on collagenase
activity was measured with an enzyme
kitc using quenched uorescent gelatin
and clostridium collagenase IV, a generic
metalloproteinase. e test materials
included aqueous solutions in the fol-
lowing concentrations: 1,000 µg/mL,
100 µg/mL, 10 µg/mL and 1 µg/mL and
were made from 10 mg/mL stock in
dimethyl sulfoxide (DMSO). Each was
incubated in the presence of collagenase
substrate-quenched uorescin-linked
gelatin and the proteolytic enzyme.
Phenanthroline, a potent metallo-
Figure 1. Structure of bakuchiol Figure 2. Down regulation of 5-a-reductase expression
a Sytenol A (INCI: Bakuchiol) is a product of
Sytheon Ltd. USA.
b e Cytouor 2350 Microurometer is
manufactured by Millipore.
c e Enzcheck kit is manufactured by Molecular
Probes.
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Vol. 126, No. 7/July 2011 www.CosmeticsandToiletries.com Cosmetics & Toiletries® magazine | 505
protease (MP) inhibitor, was used as
positive control at 100 µg/mL. The
kinetics of the release of the digested
uorescent gelatin were measured at
excitation/emission wavelengths of
485/530 nm with a microuorometerd.
Elastase inhibitory activity: Baku-
chiol and retinol (50%)e were dissolved
in DMSO at 10 mg/mL. e test mate-
rials were assayed at the following nal
concentrations: 25 ug/mL, 5 ug/mL
and 1 ug/mL by incubation with pure
human neutrophil elastasef and its
substrateg, in vitro. e positive control
was an elastase substrateh, and ultra-
pure water—i.e., both biologically pure
and free of trace metals and dissolved
organics, was the negative control.
The proteolytic activity of elastase
in the presence of the test materials
was measured by following the gen-
eration of a chromophoric reaction
product at 410 nm using microplate
readerj; the experiment was performed
in triplicate.
Anti-inflammatory activity:
Cyclooxygenase (COX) inhibition by
bakuchiol and salicylic acid was mea-
sured at 37°C by monitoring oxygen
consumption using an oxygen electrode
control unitk. e COX-1 and COX-2
IC50 for bakuchiol were found to be
14.7 µg/mL and 514 µg/mL, respectively.
Clinical study: Four formulations
were clinically evaluated for their
ability to treat acne-aected skin. e
formulations included: 1% bakuchiol,
2% salicylic acid, 1% bakuchiol (and)
2% salicylic acid, and a placebo—i.e.,
with no active. Each formulation was
tested on 15 volunteers with a total of
60 volunteers (including four drop-outs)
having mild (< 10 comedones), moder-
ate (10 to 25 comedones) or severe (> 25
comedones) acne. Prior to admittance
to the study, each subject was examined
by a dermatologist and their facial skin
condition, including actual counts of
non-inammatory and inammatory
lesions, was recorded separately for the
right and le sides of the face. In the
case of female subjects, the date of onset
of last menstruation was also recorded.
Each product was applied twice daily
in an amount sucient to provide a
light coating on the face and the percent
reduction in acne was determined using
the Global Acne Grading System.18
is system takes into account both
non-inammatory and inammatory
lesions. Non-inflammatory lesions
included open comedones (blackheads)
and closed comedones (white heads
and un-inamed nodules, sometimes
called cysts); and inammatory lesions
included papules (small red bumps),
pustules (white or yellow squeezable
spots) and inamed nodules (large red
bumps).
Table 1. Comparative P. acnes inhibitory activity of bakuchiol and
salicylic acid*
Product Composition Amount (µg/mL) Zone of inhibition (mm)
Bakuchiol 0.6 (IC50)** 37
Bakuchiol 0.3 35
Salicylic acid 29.6 (IC50)** 12
Salicylic acid 14.8 No inhibition
Salicylic acid 58 12
Bakuchiol + Salicylic acid 0.3 + 14.8 27
Bakuchiol + Salicylic acid 0.6 + 29.6 46
Bakuchiol + Salicylic acid 0.6 + 59.2 60
Bakuchiol + Salicylic acid 0.6 + 148 62
* Zone of inhibition in mm at 48 hr, incubation at 37°C
** The inhibitory concentration (IC50) of bakuchiol and salicylic acid were defined as the inhibitory
concentration of a product limiting the turbidity to < 0.02 AU at 610nm.
d e Cytouor 2350 microuorometer is
manufactured by Millipore.
e Retinol 50 C (INCI: Retinol (and) Polysorbate
20) is a product of BASF.
f Neutrophil elastase (cat. # 324681, lot# B74630),
is manufactured by Calbiochem.
g Elastase Substrate VIII, Suc-Ala-Ala-Ala-pNA is
manufactured by Calbiochem.
h Elastase substrate (cat. # 324745) is
manufactured by Calbiochem.
j e BioRad microplate reader is manufactured
by BioRad.
k e Oxytherm electrode unit is manufactured by
Hansatech.
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Discussion and Results
As previously described, the enzyme
5-α-reductase converts testosterone
to DHT, which binds to androgen
receptors on the sebaceous glands
and causes excessive oil production.
Excess oil obstructs the skin pores,
allowing bacterial growth that causes
inflammation, infection and visible
acne. erefore, ideally, a product that
either down-regulates the formation
of 5-α-reductase synthesis or is an
inhibitor of 5-reductase activity
could be an effective solution. The
described studied shows that bakuchiol
is eective in down-regulating the for-
mation of 5-α-reductase. At 10 µg/mL,
both b akuchiol and retinoic acid
showed approximately 40% reductions
in 5-α-reductase expression, compared
with the placebo (see Figure 2 on
Page 504).
Br oad antibacterial/ant ifu ngal
activities are also desired for anti-acne
treatments since aected skin has shown
much higher levels of Staphylococcus
and Candida.19, 20 e described study
demonstrates that bakuchiol exhibits
excellent P. acnes inhibitory activity,
and it is very eective in inhibiting
other microorganisms such as Staphy-
lococcus and Candida. e minimum
inhibitory concentrations (MIC, in µg/
mL) of bakuchiol were 1 µg/mL for
Staphylococcus aureus, 2 µg/mL for
S. epidermidis and 1.5 µg/mL for Can-
dida albicans. Further, while salicylic
acid is a poor inhibitor of P. acnes, at
certain concentrations, bakuchiol in
combination with salicylic acid was
found to be synergistic in inhibiting
P. acnes (see Table 1). In comparison,
a recent clinical study showed that
retinoids such as retinoic acid and
retinol did not exhibit any antibacterial
activity, whereas retinaldehyde was an
eective inhibitor of Staphylococcus and
Candida.21
Literature also has reported that
matrix metalloprotease (MMP) levels
in acne-aected skin are much higher
than in normal skin22, 23 and they play
a predominant role in inammatory
matrix remodeling and hyperprolifera-
tive skin disorders. In addition, MMPs
cause destruction of extracellular matrix
proteins like collagen, fibronectin,
laminin and elastin. Diminishing the
presence of matrix-degrading enzymes
in the acne lesion reduces imperfect
repair of the skin and thus decreases
scarring in acne-aected skin.
In relation, the described study
determined that the collagenase inhibi-
tory concentration 50% (IC50) for
bakuchiol was ~0.1% w/w, whereas
bakuchiol had a clear inhibitory activ-
ity at all concentrations tested against
elastase. In contrast, the described study
showed that retinol had no statistically
signicant elastase-inhibitory eect at
all concentrations tested; the elastase
inhibitory activity (IC50 value) for
bakuchiol was found to be between
1 µg/mL and 5 µg/mL, but a trend
toward reverse dose-response was
observed. EI III completely blocked
elastase activity, demonstrating the
technical success of the experiment.
Inammation is another severe prob-
lem in acne-aected skin. Unfortunately,
few options are available to directly treat
the inflammation that accompanies
acne. However, the described studies
show that bakuchiol has a moderate
inhibitory activity against COX-2 (IC50
514 µg/mL) and a strong inhibitory activ-
ity against COX-1 (IC50 14.7 µg/mL).
In addition, a large amount of nitric
oxide (NO) production following the
induction of inducible NO synthase
(iNOS) gene has been implicated in the
pathogenesis of inammatory diseases.
Literature has shown bakuchiol to be
eective in inhibiting the expression of
inducible nitric oxide synthase genes
via the inactivation of nuclear transcrip-
tion factor-κB in mouse leukaemic
monocyte macrophage cell lines (RAW
264.7) macrophages.24 Interestingly,
retinol was not found to be an iNOS
inhibitor whereas retinoic acid was.25
Further, bakuchiol is a weak inhibitor of
phospholipase A2 but dose-dependently
inhibits the formation of leukotriene B4
and thromboxane B2.26
It should be noted that the oxidative
breakdown of squalene and other skin
lipids may not merely be a consequence
of the acne process; it was suggested
by Lorincz in 1965 that lipid peroxides
might be directly acnegenic to the
skin.27, 28 In a small, controlled pilot
study (n = 15), Lorincz also found
clinical success using topical alpha-
tocopherol (0.05%) to treat acne aer
one month of evaluation by an inde-
pendent examiner.27 Further support to
the lipid peroxidation hypothesis came
from Tappel, who reported in 1975 that
lipid peroxidation is evident in acne and
that localized free radical damage and
peroxides might be involved in initiat-
ing damaging inammatory reactions.29
Other investigators also reported that
components of sebum, particularly
squalene, show enhanced comedogenic-
ity when oxidized.30 Squalene was shown
to be highly sensitive to oxidation and
researchers reported that both squalene
and its oxidized metabolites are found at
Table 2. Antioxidant profile of bakuchiol
Peroxyl1 Hydroxyl2 Superoxide3 Peroxynitrile1 Singlet oxygen4 Lipid peroxidation5
Bakuchiol 15,165 74 10.18 130 265 0.5
Tocopherol
natural 813 None None 1 220 30
Note: This work was carried out by Brunswick Laboratories, Norton, MA USA.
1 µmole Trolox equivalent/g; Oxygen Radical Absorption Capacity (ORAClipo)
2 µmole caffeic acid equivalent/g
3 Kilo unit SOD equivalent/g
4 Singlet oxygen was generated by using H2O2 + molybdate anion; data is expressed in IC50 in µg/mL.
5 Squalene was used for lipid peroxidation inhibitory activity; data is expressed in IC50 in µg/mL.
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much higher levels in acne vs. healthy
controls.28, 31
Another recent clinical study con-
firmed the role of reactive oxygen
species in the inammation of acne
by determining the activity of anti-
oxidant defense enzymes in leukocytes.32
Included in the study were 52 patients
with papulopustular type acne vulgaris
and 36 healthy controls, and the sever-
ity of the disease was examined by the
Global Acne Grading System. e activi-
ties of superoxide dismutase (SOD),
glutathione peroxidase and catalase
enzymes as well as the level of thiobar-
butric acid reactive substances (TBARS)
were determined in leukocytes. The
activities of SOD and glutathione per-
oxidase were found to be signicantly
decreased in the acne group. Catalase
and TBARS levels were higher in
patients than the control group, and
only a poor correlation was detected
between glutathione peroxidase activity
and severity of the disease. Authors
suggested that antioxidants be included
in the acne treatment regimen.
e described study also showed that
bakuchiol has broad-spectrum anti-
oxidant activity and eectively quenches
superoxide-, hydroxy-, peroxy-, per-
oxynitrile radicals and singlet oxygen
non-radicals in addition to inhibiting
lipid peroxidation (see Table 2 on
Page 506). Further, the literature has
shown bakuchiol to eectively reduce
lipid peroxidation,33 protect mitochon-
dria from NADPH-dependant and
ascorbate-induced lipid peroxidation,34
and protect mitochondrial respira-
tory enzyme activities against both
NADPH-dependant and dihydroxyfu-
marate-induced peroxidation injury.35
Squa lene is part ic ularly prone to
photooxidation during sun exposure,36
and bakuchiol is expected to protect
Table 3. Percent reduction in acne after product treatment
Group # Type of lotions No. of volunteers % reduction in acne
after 2 weeks after 4 weeks after 6 weeks
1 1% bakuchiol 13* 30 42 57
2 2% salicylic acid 14** 21 34 48
3 1% bakuchiol (and)
2% salicylic acid 14* 26 48 67
4 Control 15 5 5 11
*Two drop-out due to protocol violation ** One drop-out due to protocol violation
Figure 3. Treatment with 1% bakuchiol lotion a) at baseline, and b) after six weeks
of treatment
Figure 4. Treatment with 1% bakuchiol lotion a) at baseline, and b) after six weeks
of treatment
a)
a)
b)
b)
squalene and other skin lipids from
oxidation due its excellent lipid peroxi-
dation inhibitory activity (see Table 2).
Finally, the pilot clinical study
demonstrated that bakuchiol eectively
reduces acne and is more effective
when combined with salicylic acid.
e percent reduction in acne using
the Global Acne Grading System14
is summarized in Tab l e 3. Based on
the results, formulations containing
1% bakuchiol (and) 2% salicylic acid
showed a nearly 70% reduction in acne
lesions and inammation, as judged by
the acne grading system. e next best
results were with 1% bakuchiol, which
reduced acne by a score of about 57%,
whereas 2% salicylic acid only reduced
acne by about 48%. As expected, the
control group provided practically
no improvement in the reduction of
acne. None of the subjects observed
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or reported any adverse reaction using
these formulated products. ese results
clearly show that bakuchiol is an eec-
tive ingredient (see Figures 3 and 4 on
Page 508), especially when combined
with an exfoliating agent like salicylic
acid, for the treatment of acne.
Formulating With Bakuchiol
Bakuchiol is miscible with a wide
variety of emollients including capric/
caprylic triglycerides, C12–15 alkyl benzo-
ates, and mineral oils; vegetable oils;
and silicones such as dimethicones and
cyclomethicones. To use bakuchiol, it
must be dissolved in the appropriate
hydrophobic emollient(s), then added
to the formulation after making the
emulsion. Solutions of bakuchiol may
be added to formulations at a processing
temperature of about 50°C or below.
Alternately, it can be added directly
to the oil phase. For preparation of
anhydrous serums or transparent gels,
silicone derivatives such as dimethicone,
cyclomethicone, or dimethiconol (and)
dimethicone crosspolymer may be used.
Contact with iron or copper com-
pounds must be avoided as bakuchiol is
a phenolic compound, which by nature,
tends to become colored in the presence
of metal ions, although the addition of
a small amount of disodium EDTA,
0.05%, resolves this problem. The
recommended use level of bakuchiol
is from 0.5% to 1% w/w of nished
formulation and an acidic pH (< 6.5) is
necessary. Finally, bakuchiol was found
to be compatible with both salicylic acid
and benzoyl peroxide as evidenced from
stable formulations containing these
two anti-acne ingredients.
Conclusion
Phenol, 4-[1E, 3S)-3-ethenyl-3,
7-dimethyl-1, 6-octadienyl (bakuchiol),
a meroterpene of plant origin, shows
promise as a new agent that can comple-
ment and enhance the eectiveness of
currently available anti-acne formula-
tions. Bakuchiol is likely the only agent
aer retinoic acid shown to be eective
against multiple pathophysiologic
features of acne.
Further, bakuchiol has an excellent
safety prole and was shown to be non-
irritating and non-sensitizing based on
human repeat insult patch testing (data
not shown), has no photo- or hydrolytic
stability issues, and thus can be used
throughout the day. Topical formula-
tions that include bakuchiol are likely
to lead to further improvements in the
way the industry treats skin infected by
acne and beyond.
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CT1107_Chaudhuri.fcx.indd 510 6/9/11 9:47:04 AM
... 18 Interestingly, the 4-hydroxystyryl functionality present in bakuchiol is also present in resveratrol (Figure 1.2). 19 Bakuchiol possesses antioxidant, [20][21][22][23] anti-inflammatory 24,10,25,26, anti-bacterial, 27 anti-tumor, 28,29 cytotoxic, 30 heptaprotective, 31 and caspase-3 dependent apoptosis 32 properties. The cytotoxicity of bakuchiol is mainly due to its DNA polymerase 1 inhibiting activity. ...
... In validation of the foregoing effect, Chaudhuri and Marchio have recently shown that bakuchiol has broad-spectrum antioxidant activity (in vitro) and effectively quenches superoxide-, hydroxy-, peroxy-, peroxynitrile radicals, and singlet oxygen non-radical in addition to inhibiting lipid peroxidation. 23 As presented in Table 1.2, its antioxidant profile, especially with respect to lipid peroxidation inhibitory activity, is far superior to natural tocopherol, a common topical antioxidant. Bakuchiol was found to be 60-fold more effective in inhibiting squalene than natural tocopherol (IC 50 for bakuchiol 0.5 µg/mL vs. natural tocopherol 30 µg/mL). ...
... 44 Bakuchiol has moderate inhibitory activities against both 5-lipooxygenase (IC 50 23.5 µM) 24 and cyclooxygenase-1 and -2 (IC 50 14.7 and 514 µg/mL). 23 Studies have revealed that bakuchiol is a weak inhibitor of secretory and intracellular phospholipase A2 (PLA2) but dose-dependently reduced the formation of leukotirene B4 (LTB4) and thrombaxane B2 (TXB2) by human neutrophils and platelet microsomes, respectively. 24 Additionally, bakuchiol inhibited degranulation in human neutrophils, whereas superoxide generation was not affected. ...
... Recently, bakuchiol and ameroterpene phenol of plant origin, promising a new agent as a complement, enhance the effectiveness of the currently marketed available anti-acne formulations. In addition, it also possesses an excellent safety profile and proves to be nonirritant, non-sensitized and, therefore, can be used throughout the day [25,26]. Psoralen and bakuchiol ameliorated bone resorption via inhibition of AKT and AP-1 pathways activation in vitro [26]. ...
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Psoralea corylifolia L. (P. corylifolia) has been used as an oriental phytomedicine to treat coldness of hands and feet in bone marrow injury. Hydroxyapatite is usually used for tooth regeneration. In this study, the role of P. corylifolia and bakuchiol, a compound originated from P. corylifolia as differentiation-inducing substances for tooth regeneration, was determined by monitoring odontogenic differentiation in human dental pulp stem cells (hDPSCs). We confirmed that P. corylifolia extracts and bakuchiol increased the odontogenic differentiation of hDPSCs. In addition, the expression of the odontogenic differentiation marker genes alkaline phosphatase (APL), Runt-related transcription factor 2 (RUNX-2), osteocalcin (OC), and dentin matrix acidic phosphoprotein-1 (DMP-1) was proved by real-time polymerase chain reaction, and protein expression of dentin matrix acidic phosphoprotein-1 (DMP-1) and dentin sialophosphoprotein (DSPP) was proved by western blotting. Further, by confirming the increase in small mothers against decapentaplegia (SMAD) 1/5/8 phosphorylation, the SMAD signaling pathway was found to increase the differentiation of odontoblasts. This study confirmed that P. corylifolia L. extracts and bakuchiol alone promote odontogenic differentiation in hDPSCs. These results suggest that bakuchiol from P. corylifolia is responsible for odontogenic differentiation, and they encourage future in vivo studies on dentin regeneration.
... One notable example is bakuchiol, a meroterpene which occurs in Psoralea corylifolia. Bakuchiol exhibits antioxidant and anti-inflammatory activities as well as possesses retinol-like antiaging properties but without the associated adverse effects [7,8]. ...
Preprint
Full-text available
A face serum composed of a combination of biologically active compounds was evaluated for safety and efficacy in vitro, in a repeat insult patch test and in a human clinical efficacy trial. The serum inhibited tyrosinase activity modestly, decreased collagenase activity and exhibited notable free radical scavenging activity in vitro. It is gentle to the skin, as the serum did not irritate the skin or produce symptoms of allergic contact dermatitis in the 55 healthy adults that participated in the repeat insult patch test. In the efficacy trial, daily application of the face serum for 30 days significantly increased skin hydration, with all 35 volunteers experiencing improvement. Substantial improvements in skin elasticity, roughness (fine lines and wrinkles), and brightness also occurred during the trial. Dermatological examination also revealed a trend for reduced comedone count with use of the serum. Self-assessment responses revealed that all volunteers experienced improvements in multiple skin quality parameters and that participant perceptions are consistent with the results of the instrumental analyses. These findings indicated that the measured improvements in skin quality are not only statistically significant but are also clinically relevant as they were great enough for users of the face serum to feel and recognize.
... In a pilot study with 54 volunteers in four groups (A: control, B: 2% salicylic acid, C: 1% Bakuchiol and D: 2% salicylic acid and 1% Bakuchiol) it was shown that Bakuchiol alone clears 42% of the acne in 4 weeks, whereas salicylic acid clears 34% and the combination of the two clears 48% of the acne. In the untreated control group, the clearing of acne was 5% after 4 weeks [43]. Bakuchiol has also been tested for 12 weeks on 50 healthy volunteers aged 40-55 as an anti-photoaging agent when formulated at 0.5% in topical creams. ...
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Full-text available
The interaction of ultraviolet radiation with biological matter results in direct damage such as pyrimidine dimers in DNA. It also results in indirect damage provoked by the production of reactive oxygen species (ROS) catalyzed by photosensitizers. Photosensitizers can be endogenous (e.g., tryptophan) or exogenous (e.g., TiO2 and other photostable UVA sunscreens). Direct damage triggers an inflammatory response and the oxidative and proteolytic bursts that characterize its onset. The inflammatory reaction multiplies the effects of one single photon. Indirect damage, such as the peroxidative cascade in membrane lipids, can extend to thousands of molecular modifications per absorbed photon. Sunscreens should therefore be formulated in the presence of appropriate antioxidants. Superoxide and singlet oxygen are the main ROS that need to be tackled: this review describes some of the molecular, biochemical, cellular, and clinical consequences of exposure to UV radiation as well as some results associated with scavengers and quenchers of superoxide and singlet oxygen, as well as with inhibitors of singlet oxygen production.
... Bakuchiol has shown diverse therapeutic properties including antibacterial and anticancer activities [19][20][21]. It is also reported to exhibit effectiveness towards pathophysiologic features of acne [22], suggesting its potential use in cosmetic formulation. Therefore, the present study aimed at investigating the antifungal properties of bakuchiol on oral-associated Candida species. ...
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Bakuchiol is an active component of Psoralea glandulosa and Psoralea corylifolia, used in traditional Chinese medicine. The study aimed at investigating the antifungal activity of bakuchiol on planktonic and biofilm forms of orally associated Candida species. The antifungal susceptibility testing was determined by the broth micro dilution technique. Growth kinetics and cell surface hydrophobicity (CSH) of Candida were measured to assess the inhibitory effect of bakuchiol on Candida planktonic cells. Biofilm biomass and cellular metabolic activity were quantitatively estimated by the crystal violet (CV) and the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) assays. All Candida strains have been shown to be susceptible to bakuchiol with the MIC ranges from 12.5 to 100 μg/mL. Significant decrease in specific growth rates and viable counts demonstrates the inhibitory effect of bakuchiol on Candida planktonic cells. A brief exposure to bakuchiol also reduced CSH of Candida ( P < 0.05 ), indicating altered surface properties of yeast cells towards hydrophobic interfaces. Biofilm biomass and cell metabolic activity were mostly decreased, except for C. glabrata ( P = 0.29 ). The antifungal properties of bakuchiol on Candida species in this in vitro study may give insights into the application in therapeutic strategy against Candida infections.
... 이 성분은 항암, 항산화 및 간 보호 활성 작용을 가질 뿐만 아니라 구강내 병원균에 대한 항균효과 때문에 충치 예방과 치료를 위해 식품 첨가물 및 가글제로의 개발 가능성이 큰 것으로 보고되 어 왔다[15][16][17]. 또한, 바쿠치올은 여러 가지 질병 예방 및 치료에 사용하기 위한 생물학적 활성을 가지는 천연물로서 화장품 분야에서도 여드름 및 아토피 치료제의 가능성이 검토 되어 최근 여드름 치료에 탁월한 효과를 얻은 바 있다[18]. 반면에 바쿠치올은 여러 가지 우수한 효능을 나타내지만 빛 과 열에 의한 안정성이 떨어지는 등의 문제점이 있는 것으 로 알려져 있다.따라서 본 연구에서는 상기의 문제점을 보완하고 여러 가 지 효능으로 주목받고 있는 바쿠치올을 함유하는 보골지 추 출물의 피부 적용 가능성을 알아보기 위하여 보골지 추출물 을 liposome, niosome 및 transfersome과 같은 생체 이용률 촉진 시스템 (BAES)에 적용하여 이들의 안정성을 평가하고 피부 투과에 미치는 영향을 평가하였다.Niosome은 고형 지질을 95~105℃에서 용해한 후, 수상 을 넣어 충분히 팽윤하고 마이크로플루다이저 (70~75℃, 1000 bar)를 1회 통과시켜 1차 분산액을 제조하였다. ...
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Psolarea corylifolia extract that contains bakuchiol is known to have anti-microbial, anti-inflammatory and anti-scarring effects. In this study, a vesicles such as liposome, niosome, and transfersome were produced to encapsulate P. corylifolia extract and measured their stability and physiochemical property. The skin permeation and partitioning of P. corylifolia extract in the vesicles were elucidated in nude mouse skin by using Franz diffusion cells after topical application for 24 h. After storage at 25, 40, 70^{\circ}C, and light, the stability of bakuchiol incorporated into the vesicles was maintained for 30 days. The optimal concentration of P. corylifolia extract entrapped into the vesicles was found to be 5~10%. From the physicochemical studies, after storage at 4, 25, and 40^{\circ}C, the viscosity and particle size of the vesicles remained in 30~80 cP and the nanosize range for 6 months, respectively. From the permeation experiments, niosome showed a higher amount of bakuchiol permeated through the mouse skin compared to liposome and transfersome after 24 h. From these results, niosome and transfersome could be a good bioavailability enhancement system (BAES) for P. corylifolia extract to improve the skin permeation and stability.
... It has broad spectrum antioxidant activity, effectively quenches superoxide, hydroxy, peroxy, peroxynitrile radicals, and singlet oxygen non radicals in addition to inhibiting lipid peroxidation. A pilot clinical study showed that 1% bakuchiol reduced acne by a score of about 57%, whereas 2% salicylic acid only reduced acne by about 48%, but when used in combination it reduced acne lesions and inflammation upto 70% [112]. It has been reported that the fruits and root of A. dahurica containing imperatorin, phellopterin, xantoroxin, byakangelcol, oxypeucedanin, neobyakangelcol, and coumarin markedly suppressed neutrophil chemotaxis. ...
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Full-text available
Acne is a common but serious skin disease, which affects approximately 80% adolescents and young adults in 11-30 age group. 42.5% of men and 50.9% of women continue to suffer from this disease into their twenties. Bacterial resistance is now at the alarming stage due to the irrational use of antibiotics. Hence, search for new lead molecule/bioactive and rational delivery of the existing drug (for better therapeutic effect) to the site of action is the need of the hour. Plants and plant-derived products have been an integral part of health care system since time immemorial. Therefore, plants that are currently used for the treatment of acne and those with a high potential are summarized in the present review. Most active plant extracts, namely, P. granatum, M. alba, A. anomala, and M. aquifolium exhibit minimum inhibitory concentration (MIC) in the range of 4-50 µg/mL against P. acnes, while aromatic oils of C. obovoides, C. natsudaidai, C. japonica, and C. nardus possess MICs 0.005-0.6 μL/mL and phytomolecules such as rhodomyrtone, pulsaquinone, hydropulsaquinone, honokiol, magnolol, xanthohumol lupulones, chebulagic acid and rhinacanthin-C show MIC in the range of 0.5-12.5 μg/mL. Novel drug delivery strategies of important plant leads in the treatment of acne have also been discussed.
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Background: Patients with sensitive skin find topical retinoid use for anti-aging purposes challenging due to irritation. Bakuchiol, a meroterpene from the Psoralea corylifolia seed, has retinol functionality through retinol-like regulation of gene expression. Objective: This research examined the tolerability, efficacy, and barrier effects of a nature-based bakuchiol-containing cleanser and moisturizer in subjects with sensitive skin. Methods: 60 female subjects Fitzpatrick skin types I–V age 40–65 years with sensitive mild to moderate photodamaged skin were enrolled in this 12 week study. A sensitive skin panel was constructed: 1/3 eczema/atopic dermatitis, 1/3 rosacea, 1/3 cosmetic intolerance syndrome. Subjects used a nature-based cleanser and moisturizer twice daily and underwent transepidermal water loss (TEWL), corneometry, tolerability assessments, and efficacy assessments at baseline, 5–10 minutes post-application, and week 4. Results: The skin care products were well tolerated and efficacious (P<0.001) in terms of investigator assessed improvement in visual smoothness, tactile smoothness, clarity, radiance, overall appearance, and global anti-aging. Cheek corneometry measurements demonstrated a statistically significant 16% increase in skin moisture content (P<0.001). Conclusion: A bakuchiol nature-based anti-aging moisturizer is well tolerated and effective in individuals with sensitive skin.J Drugs Dermatol. 2020;19(12): doi:10.36849/JDD.2020.5522.
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An in vitro study of the oxidation of squalene, and a description of factors acting on this transformation are presented. Thin layer chromatography was used to quantify the products generated by different oxidation processes. The results clearly show that squalene is a highly effective oxygen-scavenging agent. Its oxidation may first induce comedogenesis and, as a secondary event, cause a large reduction in oxygen tension in the human pilo-sebaceous duct. Porphyrins were confirmed to be highly efficient catalytic factors in the squalene oxidation process. The relationships between comedogenesis, bacterial colonization, and the role of sebum in the pathogenesis of acne are discussed in the light of these findings.
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