dr freedman study - topical polyphenolic antioxidants augment the efficacy of ipl

Topical antioxidant application augments the effects of intensepulsed light therapy

Bruce M Freedman, MD, FACS

Plastic Surgery Associates of Northern Virginia, McLean, VA

Summary Background There has been great interest in improving the efficacy of nonablative

technologies by combining them during facial skin rejuvenation. The purpose of this

study was to determine whether the addition of topical polyphenolic antioxidants to an

intense pulsed light (IPL) treatment regimen augmented the effects of facial IPL

treatments.

Methods Thirty female volunteers, ages 34–52, with skin phototypes 1–3 were ran-

domly assigned into three groups: group A (n = 10) received three full-face IPL treat-

ments spaced 3 weeks apart; group B (n = 10) underwent 6-weekly full-face treatments

of a pneumatically applied topical polyphenolic antioxidant solution; group C (n = 10)

received the combination of the three full-face IPL treatments and the six full-face

topical antioxidant applications. Skin biopsies, skin polyphenolic antioxidant levels, and

skin moisture content levels were obtained and clinical efficacy variables were noted

prior to and following the treatment period.

Results Compared to group A, group C demonstrated significantly greater epidermal and

papillary dermal thickness, decreased lipid peroxide concentration, increased skin

moisture content, and increased polyphenolic antioxidants levels (P < 0.05). There was

qualitative improvement in hydration, texture, and pore size. Compared to group B,

group C demonstrated significantly greater papillary dermal thickness (P < 0.05), and

qualitative improvement in reduction of fine lines, reduction of hyperpigmentation, and

skin dullness. group B and group C had equivalent polyphenolic antioxidant levels, lipid

peroxide concentration, and epidermal thickness.

Conclusion The addition of polyphenolic antioxidants to an IPL regimen improved the

clinical, biochemical, and histological changes seen following IPL treatment alone.

These data support the use of multimodal therapy to create synergy and to optimize

clinical outcomes in nonablative facial skin rejuvenation.

Keywords: intense pulsed light, topical antioxidants, facial rejuvenation

Introduction

In 1994, intense pulsed light (IPL) technology became

commercially available for use in treatment of vascular

anomalies of the skin. Over the following decade, IPL

technology has undergone a series of modifications and

innovations that have broadened its clinical use. IPL has

since become a widely accepted and reliable technique

for the treatment of photodamaged skin. IPL systems

utilize high intensity flashlamps that emit pulses of

polychromatic light in the 515–1200 nm wavelength

spectrum, utilizing the mechanism of selective photo-

thermolysis to target dermal chromophores. The

Correspondence: Bruce M Freedman, MD, 8180 Greensboro Drive #1015,

McLean, VA 22102, USA. E-mail: [email protected]

Presented at the ASLMS Annual Meeting, Washington, DC, April 1–5, 2009.

Accepted for publication July 26, 2009

Original Contribution

254 � 2009 Wiley Periodicals, Inc. • Journal of Cosmetic Dermatology, 8, 254–259

resulting thermal injury affects the dermal vasculature

and initiates a cascade of inflammatory events that

includes fibroblastic proliferation and an increase in

collagen production.1 This type of dermal remodeling is

well suited for nonablative facial rejuvenation. Numer-

ous studies have confirmed that a series of IPL

treatments can decrease facial rhytides, improve skin

texture, correct irregular pigmentation, and reduce

telangiectasis.2,3

The employment of different nonablative technologies

has recently been promoted to improve results and reduce

recovery time. Typically, topical compounds such as

photosensitizing agents or exfoliating acids have been

used in conjunction with microdermabrasion or IPL to

provide multimodal therapy.4,5 Recently, there has been

great interest in exploring the effects of topical antioxi-

dants on the skin. Botanically derived extracts from green

tea, rosemary, and horse chestnut seeds contain polyphe-

nolic compounds that posses significant antioxidant

properties. These polyphenols (i.e., the epicatechins) have

demonstrated an ability to prevent ultraviolet radiation-

induced lipid peroxidation, DNA damage, and carcino-

genesis.6–9 Clinically, topically applied polyphenolic

antioxidants have been shown to decrease inflammation,

prevent erythema, and reverse photoaging.10–12

The purpose of this study was to determine whether

the addition of topically applied polyphenolic antioxi-

dants could augment the effects of IPL therapy in facial

rejuvenation.

Materials and methods

Thirty female volunteers, with Fitzpatrick skin types I-III,

aged 38–52, were randomized into three groups. All

participants consented to partake in a prospective study

to evaluate the effects of IPL and antioxidant application

on facial skin in accordance to the guidelines of the

1975 Declaration of Helsinki.

Group A (n = 10) received three full-face IPL treat-

ments spaced 3 weeks apart delivered by a Sciton Profile

System using the Broad Based Light module (Sciton

Corporation, Palo Alto, CA, USA) set at the following

parameters: 16 J ⁄ cm2, 10 ms, 560 nm filter. This cor-

responded to a calculated fluence rate of 2500 W ⁄ cm2.

Group B (n = 10) underwent six full-face treatments at

7- to 10-day intervals with the HydraFacial Wave

System (Edge Systems Corporation, Signal Hill, CA,

USA). Each treatment consisted of one pass over the

entire face with the spiral tip hand piece of the crystal

free microdermabrasion unit set at 180 mm Hg. A

polyphenolic based antioxidant serum containing poly-

phenolic flavonoids and polyphenolic diterpenes (e.g.,

epigallocatechin, ursolic acid) was pneumatically ap-

plied to the face at 180 mm Hg. The solution contained

no humectants or hydrating agents. Group C (n = 10)

received the combination of the three full-face IPL

treatments at 3-week intervals and the six full-face

topical antioxidant applications at 7- to 10-day inter-

vals. During those weeks when both treatments were

administered, the antioxidant application was performed

immediately prior to the IPL treatment. Skin care

products such as antioxidants, triretinoin, and glycolic

acid agents were avoided 6 weeks prior to and during

the treatment period.

In all groups, digital photographs, 2 mm full-thickness

preauricular skin biopsies, skin moisture content, and

skin polyphenolic antioxidant levels were obtained prior

to treatment (control) and 1 week following the last

treatment session. Side effects such as persistent ery-

thema and blistering following treatment were also

recorded.

Skin antioxidant levels

Skin polyphenolic antioxidant levels were obtained from

the left cheek using a noninvasive optical device

(Biophotonic Scanner, Pharmanex, Provo, UT, USA).

This technology employed laser energy at 473 nm and

10 mW power to stimulate molecules containing car-

bon-carbon double bonds generating an optical finger-

print. The emitted backscattered light was captured by a

sensitive light detector, which was then processed and

calculated using a Raman scattering spectroscopic

technique that has been validated in humans in vivo.13

Using a spectral Raman peak at 1520 cm)1, a linear

relationship has been established between antioxidant

concentration and Raman intensity, indicating that

absolute Raman intensity counts are a biomarker for

skin antioxidant levels.14,15

Lipid peroxidation

The skin biopsies for lipid peroxide analysis were frozen

until assayed. Lipid peroxidation was assessed by deter-

mining the concentration of cutaneous lipid peroxides as

described by Sorg et al.16 Briefly, skin samples were

homogenized in methanol containing butylated hydro-

xytoluene. The homogenates were sonicated and cen-

trifuged and the supernatant separated into two 500 mL

aliquots. One aliquot was incubated with 50 mL of

10 mM triphenylphosphine in methanol while 50 mL

methanol was added to the other aliquot. A 500-mL

mixture containing 25 mM sulfuric acid, 200 mM

ammonium ferrous sulfate, 100 mM xylenol orange,

� 2009 Wiley Periodicals, Inc. • Journal of Cosmetic Dermatology, 8, 254–259 255

Topical antioxidants augment IPL therapy • B M Freedman

and 4 mM butylated hydroxytoluene in 90% methanol

was then added to both aliquots; optical density was

read at 585 nm 1 h later. The specific lipid peroxide

signal was obtained by subtracting the nonspecific signal

(triphenylphosphine) from the global signal. Lipid per-

oxide concentration was determined using cumene

peroxide as a standard.

Histological assessment

The skin biopsies for histology were fixed in a 10%

buffered formaldehyde solution, embedded in paraffin,

and cut in 4-lm sections. Sections were stained with

standard hematoxylin and eosin for light microscopy.

The slides were reviewed in a blinded fashion to evaluate

epidermal and papillary dermal thickness as well as

epidermal and dermal cellular and extracellular ele-

ments. The slides were examined with an Olympus

Microscope and precision measurements were performed

using an Olympus (Olympus Corporation, Tokyo, Japan)

Micrometer at 40· magnification.

Skin moisture content

Water content detection was obtained utilizing interdig-

ital capacitance polyimide film sensor technology.17 Skin

moisture content was measured by calculating skin

capacitivity using a noninvasive skin probe (MoistSense

Skin Sensor, Moritex Corporation, Tokyo, Japan). This

methodology was based on determining the dielectric

constant or relative permittivity of the skin; all mea-

surements were taken under fixed environmental con-

ditions of 23 �C and 50% relative humidity.

Clinical assessment

A panel of three independent medical clinicians examined

each of the patients before and after the study period.

Efficacy variables were scored on a 0–9 scale (0 = none,

9 = severe) for the following skin attributes: (1) fine lines;

(2) pore size; (3) hyperpigmentation; (4) dullness; and (5)

skin texture.18 Differences in clinical outcome for each

skin attribute were tabulated as changes from mean score

baseline (control) in each patient.

Statistical analysis

The Pearson’s chi-square test was used to compare

treatment groups A, B, and C with respect to age,

gender, and skin types. These parameters were found to

be similar indicating that the patients had been effec-

tively randomized such that the subject variables did not

influence outcome. Therefore a two-sided paired t-test

was used to identify statistical differences in epidermal

and papillary dermal thickness, skin moisture content,

lipid peroxide concentration, skin polyphenolic antioxi-

dant levels, and side effects between groups. A P-value of

less than or equal to 0.05 was used to declare statistical

significance. The Wilcoxon signed ranks test was used to

evaluate the change from baseline (control) in the

clinical efficacy variables. Statistical significance was set

a priori at P < 0.05.

Results

After the treatment protocol, the epidermal thickness in

group B increased to 75 ± 9 lm, and in group C

increased to 80 ± 8 lm. These values were statistically

greater than the control epidermal thickness of

50 ± 5 lm (P < 0.05). However, the epidermal thick-

ness in group A did not increase statistically after

treatment. In addition, the epidermal thickness in group

C was equivalent to that found in group B. After the

treatment protocol, the papillary dermal thickness in

group A increased to 370 ± 20 lm, in group B

increased to 360 ± 30 lm, and in group C increased

to 475 ± 40 lm. These values were statistically greater

than the control papillary dermal thickness of

285 ± 20 lm (P < 0.05). Also, the papillary dermal

thickness in group C was statistically greater than that

in both groups A and B (P < 0.05).

The Raman intensity count, a reflection of skin

polyphenolic antioxidant levels, averaged 16 000 ±

2000 in the control tissue. In group A (IPL alone), the

Raman intensity count decreased significantly to

12 000 ± 2000, while in group B (antioxidant alone)

it increased significantly to 24 000 ± 3000 (P < 0.05).

In group C (IPL plus antioxidant), the Raman intensity

count averaged 20 000 ± 2000, a value statistically

greater than in both the control and group A

(P < 0.05). However, this value was statistically less

than that in group C. Lipid peroxide concentration in

group A increased significantly to 260 ± 30 nmol ⁄ gfrom a control value of 60 ± 10 nmol ⁄ g (P < 0.05).

Lipid peroxide concentration in groups B and C did not

increase relative to control and was significantly less

than that found in group A. In group A skin moisture

content was significantly reduced to 35 ± 6 IU from the

control level of 45 ± 5, whereas in group B skin

moisture increased significantly 71 ± 5 (P < 0.05).

However, in group C the skin moisture content was

59 ± 9, a level greater than in control and group A,

but less than in group B. These data are depicted in

Table 1.



Changes in the clinical efficacy variables are depicted

in Figure 1. At the end of the study periods groups A, B,

and C showed a significant improvement from baseline

in fine lines (P < 05). However, group C demonstrated

statistically greater improvement than groups A and B

(P < 0.05). Pore size in all groups was reduced relative

to control, but equivalent between groups. Following

treatment, groups A, B and C showed a significant

improvement from baseline in hyperpigmentation

(P < 0.05). The improvement in groups A and C was

statistically greater when compared to the improvement

observed in group B (P < 0.05). Clinically, at the end of

the study period, all groups showed a significant

improvement from baseline in skin texture (P < 0.05).

However, group C demonstrated statistically greater

improvement than groups A and B (P < 0.05). Side

effects, particularly persistent erythema and blistering,

differed between the groups. The side effects in group A

were statistically greater than those noted in groups B

and C (Table 2). The minor blistering noted in group A

resolved without scarring.

Discussion

Minimally invasive technologies, such as IPL, have

become increasingly popular in the treatment of

photoaged skin. This trend has resulted from the overall

safety, reduced recovery time, and versatility of these

modalities. These factors have a broad appeal to clini-

cians and patients, indicating that the number of

nonablative procedures will continue to grow. In spite

of the utility of IPL in facial rejuvenation, there are some

questions concerning the predictability of results. Pub-

lished reports indicate a varied response to IPL treat-

ment. Bitter1 observed a 10–90% improvement in

rhytides, while Goldberg and Samady19 reported signif-

icant clinical improvement in only 9 out of 30 patients

after a series of IPL treatments. It has been suggested

that in some patients the repetitive photo-insult may

induce microscopic changes analogous to the dermal

scarring observed with ultraviolet associated photodam-

age.3 In these patients an exuberant inflammatory

response to high intensity visible light exposure could

lessen the overall benefits seen with IPL therapy. In an

effort to deliver optimal clinical improvement with a

reliable safety profile, recent research has focused on

combining multiple modalities to accomplish these goals.

This study sought to determine whether the addition

of topical polyphenolic antioxidants could enhance the

clinical efficacy of IPL therapy. Recently, there has been

an increased focus on antioxidants and their role in skin

health. Several antioxidants, including the botanically

extracted polyphenolic compounds, have demonstrated

anti-aging properties when applied topically. These

compounds have been shown to scavenge superoxide

anions and other radicals, prevent lipid oxidation,

reduce antigenotoxicity, and elevate the antioxidative

capacity in the skin.20,21 Collagen synthesis in the

papillary dermis and decreased elastosis have also been

attributed to topical antioxidant application.22 Fujimura

et al. demonstrated that the polyphenols in horse chest-

nut seed extract induced contraction forces in fibroblasts

resulting in decreased periorbital rhytides.23 Other

studies have suggested that polyphenolic antioxidants

can increase fibroblast density and collagen deposition

during the wound healing process.9–11,24 The effects

have been purported to translate clinically into increased

Table 1 Results comparing data between groups before treatment (control); after IPL (group A); after antioxidant application (group B);

and following IPL plus topical application of polyphenolic antioxidant solution (group C)

Control Group A Group B Group C

Epidermal thickness (microns) 50 ± 5 55 ± 7 75 ± 9*,� 80 ± 8*,�

Papillary dermal thickness (microns) 285 ± 20 370 ± 20* 360 ± 30* 475 ± 40*,�,�

Skin polyphenolic antioxidant level (Raman intensity units) 16 000 ± 2000 12 000 ± 2000* 24 000 ± 3000*,� 20 000 ± 2000*,�

Lipid peroxide concentration (nmol ⁄ g) 60 ± 5 260 ± 30* 65 ± 10� 80 ± 20�

Skin moisture content (International units) 45 ± 5 35 ± 6* 71 ± 5*,� 59 ± 9*,�,�

*P < 0.05 vs. Control; �P < 0.05 vs. Group A; �P < 0.05 vs. Group B.

Figure 1 Mean decreases from baseline score in the efficacy

variables. , Group A; , Group B; , Group C.



collagen production, ultraviolet radiation protection,

and reduction of fine lines.

The mechanism and timing of antioxidant delivery

was designed to achieve optimal results. Lee et al.

demonstrated that the flux and skin deposition of topical

antioxidants increased by approximately 20 times in

microdermabrasion-treated skin.25 Therefore, the anti-

oxidants in this study were delivered to the skin via a

crystal-free microdermabrasion technique. Other re-

search has shown that applying polyphenolic antioxi-

dants to microdermabraded skin resulted in measurably

increased levels of polyphenolic antioxidants in the

dermis.24 The polyphenolic antioxidants in this study

were applied immediately prior to each IPL treatment

and also between IPL treatments to preserve and

maintain the antioxidative capacity of the skin. A

pretreatment approach was employed based on findings

that polyphenolic antioxidants applied prior to ultravi-

olet and visible light exposure decreased measurable

DNA damage in human fibroblasts and keratinocytes.7

In addition, it has been show that antioxidants applied

topically after irradiation may not decrease oxidative

stress.22

This study demonstrated that the topical application of

polyphenolic antioxidants during IPL therapy enhanced

the known effects of IPL treatment. The benefits

conveyed by the polyphenolic antioxidants in this study

appear to be both reparative and preventative. Polyphe-

nolic antioxidants application enhanced the cellular

mechanisms activated in the skin during IPL therapy.

Papillary dermal thickness and skin moisture content,

ostensibly an indicator of skin barrier function, were

measurably increased when polyphenolic antioxidants

were applied to the skin during the course of IPL

therapy. Clinically, fine lines, texture, pore size, and

overall skin appearance were improved to a greater

extent in skin treated with the polyphenolic antioxi-

dants. These findings most likely accounted for the

histological improvement in the skin architecture as well

as the improvement in skin efficacy variables seen

following polyphenolic antioxidant addition to an IPL

regimen.

Other mechanisms by which the polyphenolic antiox-

idants appeared to exert their impact was through their

anti-inflammatory and anti-oxidative properties. This

was manifest in this study through a reduction in the

adverse effects associated with IPL therapy. Mahmoud

et al.20 reported that visible light could induce DNA

damage through the generation of reactive oxygen

species. Likewise, Sorg et al.16 demonstrated that the

moderate dose of visible light delivered during IPL

therapy increased lipid peroxide concentration in vivo.16

In this study, the pneumatic topical application of

polyphenolic antioxidants during IPL therapy mitigated

the lipid peroxide concentrations observed during a

course of IPL therapy (Figure 2). Furthermore, the

addition of polyphenolic antioxidants to an IPL regimen

decreased the incidence of erythema and blistering

(Table 2). These findings corroborate current views that

topically applied antioxidants exert anti-inflammatory

effects.

In conclusion, the addition of polyphenolic antioxi-

dants to an IPL regimen improved the clinical, biochem-

ical, and histological changes seen following IPL

treatment alone. As such, polyphenolic antioxidants

may confer a protective effect on facial skin exposed to

high-intensity visible light radiation and reduce delete-

rious effects of IPL therapy.

These data support the use of multimodal therapy to

create synergy and to optimize clinical outcomes in

nonablative facial skin rejuvenation.

Acknowledgments

The author would like to acknowledge Dr. James Henry,

Department of Pathology, Reston Hospital Center for his

assistance with the histological analysis and Jacqueline

D Higgins for her assistance with manuscript prepara-

tion and technical support.

Table 2 Side effect profile

Group A Group B Group C

Persistent erythema 3 0 1

Blistering 2 0 0

Total side effects 16% (5 ⁄ 30)* 0% 3% (1 ⁄ 30)

Each subject in groups A and C received three IPL treatments for

a total of 30 IPL exposures.

*P < 0.05.

Figure 2 Lipid peroxide concentration before treatment (control),

after IPL (group A); after antioxidant application (group B); and

following IPL plus topical application of polyphenolic antioxidant

solution (group C).



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dr freedman study - topical polyphenolic antioxidants augment the efficacy of ipl

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