Treatment of striae distensae with microdermabrasion: a clinical and

Transcription

Treatment of striae distensae with microdermabrasion: a clinical and
Treatment of striae distensae with microdermabrasion:
a clinical and molecular study
Amany M. Abdel-LatiJ; M.D. * and Amal S. Elbendary, M.D. f
*Departments of Dermatology and Venereology, ?clinical Pathology,
Faculty of Medicine, Tanta University.
Background. Striae distensae are dermal scars associated with epidermal atrophy whose treatment options
are unsatisfactory. Although microdermabrasion has become a popular method for superficial skin
resurfacing, studies examining its usefulness in treatment of striae are laclung. Objective. To evaluate the
efficacy of rnicrodermabrasion in treatment of striae and to test its effect on mRNA expression of type I
procollagen. Methods. Each of 20 patients with striae underwent a series of 5 rnicrodermabrasion treatments
at weekly intervals to their striae on one half of the body with matched striae on the other half serving as
control. From each patient, skin biopsy specimens were obtained 2 weeks after the last microdermabrasion
treatment from both treated and untreated control striae. Samples were subjected to real time RT-PCR for
assay of type I procollagen -1 mRNA levels. Results. There was good to excellent (more than 50%)
improvement in the appearance of striae in 50% of cases 12 weeks after starting 5 rnicrodermabrasion
treatments compared to control. The remaining 50% showed mild to moderate (up to 50%) improvement.
More improvement was obtained in striae rubra than striae alba. Upregulated type I procollagen a1 mRNA
expression was found in the rnicrodermabrasion treated compared to non treated striae. Conclusion.
Microderrnabrasion can be a useful therapeutic option in treatment of striae with a possible stimulatory effect
on type I procollagen formation.
Key words. Striae distensae, microdermabrasion, type I procollagen rnRNA, real time RT-PCR.
Striae are visible linear scars which form
in areas of dermal damage produced by
stretching of the skin.(') The factors which
govern the development of striae are poorly
understood. It was suggested that striae
develop as a result of stress rupture of
conpective tissue framework.
They are
common during adolescence and they seem
to be associated with rapid increase in size
of a particular regi0n.e) Striae are very
common over the abdomen and breast in
and may develop on
pregnancy "1,
shoulders in young male weight lifters
when their muscle mass rapidly increases.(5)
They are a feature of Cushing' s disease,
and may be induced by local or systemic
steroid therapy.c2) The importance of
genetic factors in determining susceptibility
of connective tissue is emphasized by
absence of striae in pregnancy in Ehler
Danlos syndrome but they are present as
one of the minor diagnostic criteria for
Marfan's syndrome. The histology is that
of scar. In the early stages, inflammatory
changes may be conspicuous but later the
epidermis is thin and flattened. The dermal
collagen bundles are arranged in straight
lines parallel to the surface in the direction
of presumed stress with abundant clumped
elastic fibers.(@ The commonest sites are
the outer aspects of the thighs and the
lumbosacral region in boys and the thighs,
upper arms, buttocks and breasts in girls. In
the early stages, striae may appear pink to
red (striae rubra), which over time become
atrophic and attain a white colour (striae
alba).
Recently,
high-resolution
epiluminescence colorimetric assessment of
J Egypt worn Dermatol Soc. Vol. 5, No. I , 2008
Amany M. Abdel-Lcctif M.D.
and Amal S. Elbenda1?1, M. D.
striae distensae distinguished four distinct
types, namely striae alba, striae rubra,
striae caerulea and striae nigra.The direct
and/or indirect influences of melanocyte
mechanobiology
appear to
have
a
prominent effect on the various colours of
striae di~tensae.'~)
Multiple treatment modalities have been
tried with variable results. These included
tretinoin,c8)glycolic acid9c9)pulsed dye laser,
(lO.ll) C 0 2 laser,(12)intense pulsed light.(I3)the
excimer laser<14-16)
and non ablative 1,450-nm
diode laser.(17)
Aluminum
oxide
crystal
rnicrodermabrasion has become a popular
method of superficial skin resurfacing.
Microdermabrasion may improve many skin
problems including acne scars,(18) acne?(l9)
skin
texture
irregularities,
mottled
pigmentation(20) and fine wrinkles-c21) In
addition, Karimipour et al, (2005) (22)
reported that microdermabrasion induces
epidermal signal transduction pathways
associated with remodeling of the dermal
matrix. However, studies documenting the
efficacy of rnicrodermabrasion in treatment
of striae are lacking.
This study was performed to evaluate
clinically
the
efficacy
of
microdermabrasion in treatment of striae
and to investigate at the molecular level its
stimulatory effect on type I procollagen
formation.
PATIENTS AND METHODS
Twenty patients with striae distensae
collected from the Out-Patient clinic of
Dermatology and Venereology department
of Tanta University hospital were included
in this study. Informed consent was obtained
from each patient. They included 14 (70%)
females and 6 (30%) males. Their ages
ranged from 18 to 35 years (mean; 26 year).
Twelve patients had striae rubra and 8
patients had striae alba. The duration of the
disease ranged from 3 months to 2 years
(mean; 9 months). The treated striae were
present on the thighs [6 (30%) cases],
abdomen [5 (25%) cases], upper arms [5
J Egypt worn Dermatol Soc. Vol. 5, No. 1, 2008
(25%) cases] and back [4 (20%) cases]. Five
(25%) patients have Fitzpatrick's skin type
11, eight (40%) have type 111, and seven
(35%) have Fitzpatrick's skin type IV. Each
patient
underwent
a
series
of
5
microdermabrasion treatments at weekly
intervals to his or her striae on one half of
the body with matched striae on the other
half serving as control.
The basic aluminum oxide/sodium
chloride-based rnicrodermabrasion system
is a closed loop consisting of the following:
vacuum suction distributed through a hand
piece that sucks the skin into the hand
piece, a compression system that propels
crystals (corundum) at a programmable
pressure when the skin is sucked into the
hand piece, a reservoir for unused
corundum, and a waste receptacle which
contains used corundum and skin debris
that have been aspirated back through the
vacuum.
Multiple
passes
with
the
microdermabrasion hand piece on the striae
were performed until a strong erythema was
visible. Photographs were taken before
microdermabrasion treatment, 2 and 8
weeks after the last treatment. All
photographs were taken with the same
Nikon coolpix-4500 digital camera (4.0
mega pixels), under similar background,
light intensity and positioning.. Three
blinded observers were asked to grade the
degree of clinical improvement based on
photographic assessment for the change in
width, colour mismatch and skin atrophy
comparing treated striae with untreated
matched control 8 weeks after the last
treatment (12 weeks following the onset of
microdermabrasion treatment). The degree
of improvement was graded by 4 point
grading scale as follows; mild (< 25%),
moderate (25-50%), good (>50%-75%) and
excellent (>75%) improvement. Patient
satisfaction was graded by 3 point grading
scale; A (not satisfied), B (somewhat
satisfied) and C (highly satisfied).
From each patient, 3 mm punch biopsy
specimens were obtained 2 weeks after the
last (6 weeks following the first)
microdermabrasion treatment, one from
treated striae and the other from matched
Trecrtment of striae distensae with microdermclbrusion:
a clitzical and moleculur study
untreated control striae. Skin s p e @ - m s were frozen at -70 oC until assay of type I
procollgen a1 mRNA levels using real time
reverse transcriptional polymerase chain
reaction (RT-PCR).
Real time RT-PCR for assay of type I
procollagen mRNA:
Total RNA extraction was performed
after
sample
homogenization
using
extraction kit QIAGEN (QIA amp RNA
mini kit Inc USA) according to the
manufacturer's instructions. 2 mg of total
RNA were reverse-transcripted using
standard reagents (Gibco, USA). The
cDNA corresponding to 20 ng of RNA
served as a template in a reaction
containing 4 mmol/L MgC12, 0.5 mmol/L
of each primer and DNA Master SYBR
(Roche
Molecular
Green
mixture
Biochemicals, USA), under the following
conditions; denaturation at 95 oC for 10
min, followed by 45 cycles, each cycle
consisting of 95 oC for 15 seconds, 60 oC
for 5 seconds and 72 oC for 10 seconds.
Fluorescence emission readings were
monitored at 72 oC at the end of each
cycle and analyzed using Light Cycler Soft
ware (Roche Molecular Biochemicals
USA). Relative amounts of type I
procollagen a1 transcript levels were
normalized to glyceraldehyde-3 phosphate
dehydrogenase (GAPDH) levels. Melting
curves were generated after each run to
confirm
amplification
of
specific
transcripts.
The sequence of primers used for real
time RT-PCR assay was: GA1, 5'CCAGCCGAGCCACATCGCTC- 3', GA2,
5'- ATGAGCCCCAGCCTTCTCCAT- 3'
(for
GAPDH)
and
5'-GTCTTCCTGGCCCCTCTGGTG-3',
5'-TCGCCCTGTTCGCCTGTCTCA-3' (for
type I procollagen a 1).cu)
Statistical analysis:
Data were analyzed with statistical
package for social science (SPSS) version
11, statistical soft ware (USA). Chi square
test and student (t) -test were utilized.
Significance was established at P value
<0.05.
RESULTS
Twelve weeks following the start of 5
microdermabrasion treatments at weekly
intervals, 4 (20%) patients showed mild
(<25%) improvement, 6 (30%) got moderate
(25-50%) improvement, 6 (30%) got good (
250%-75%) improvement and 4 (20%) got
excellent (>75%) improvement (table 1). More
improvement was noted in striae rubra than
striae alba (table 2, fig.1). In striae rubra, 1
(8.4%) patient got mild improvement, 3 (25%)
got moderate improvement, 4 (33.3%) got
good improvement, and 4 (33.3%) got
excellent improvement (fig. 2). In contrast,
patients with striae alba got mild improvement
in 3 (37.5%) cases, moderate improvement in 3
(37.5%) cases and good improvement in 2
(25%) cases and no excellent improvement
was obtained. The difference was statistically
significant (table 2). No significant differences
in the degree of improvement were observed in
different (11-IV) skin types (table 3). Side
effects were minimal and limited to post
inflammatory hyper pigmentation in 4 (20%)
cases and transient erythema in 5 (25%)
patients. Patient satisfaction scores revealed
that 8 (40%) patients were highly (C) satisfied
and 8 (40%) were somewhat (B) satisfied
while 4 (20%) were not (A) satisfied.
There was a highly significant increase in
relative amounts of type-I procollagen a 1
mRNA in treated (0.55kO. 12) compared to non
treated control (0.18k0.04) striae 6 weeks
following the start of 5 microdermabrasion
treatments.
El Mild IModerate @ Good EI Excellent
g
1
40
35
30
25
::
10
t
5
0
Striae rubra
striae alba
Degree of improvement
Fig. 1. More improvement was found in striae rubra
compared to striae alba 12 weeks following the start of
5 microderrnabrasion treatments.
J Egypt worn Dermutol Soc. Vol. 5, No. 1, 2008
Amany M. Abdel-Latif M.D.
and Amal S. Elbendary, M.D.
Table 1. Improvement of striae distensae 12 weeks
after starting 5 microdermabrasion treatments.
Degree of
improvement
Number
Percentage
Mild (~25%)
4
20%
Moderate(25%-50%)
6
30%
Good (>50%-75%)
C
30%
Excellent ( >75%)
4
20%
IStriae
rubra
(N=12)
No %
improvement
1
Mild (~25%)
Moderate(25%-50%) 3
IStriae
alba
(N=8)
No %
Mean f SD
Significant*: P. value < 0.05
Chisquare
X2
P. value
8.4 3 37.5
25
3 37.5
Good (>50%-75%) 4 33.3 2
25
4 33.3 0
0
Excellent(>75%)
I
- 1 mRNA relative
amounts
Range
Table 2. Improvement of striae rubra compared to
striae alba 12 weeks following the start of 5
microdermabrasion treatments.
Degree of
Table 4. Relative amounts of type-I procollagen -1
mRNA in skin lesions of treated compared to non
treated control striae 6 weeks following the start of
5 microdermabrasion treatments.
5.07
0.041*
Significant*: P. value c 0.05
Fig. 2(A). Striae rubra on the right upper arm before
treatment
Table 3. Improvement of striae distensae 12 weeks
following the start of 5 microdermabrasion
treatments by Fitzpatrick's skin type.
I
Chisquare
Fitzpatrick's skin type
X2
1.26
P. value
0.974
Non significant: P. value >0.05
J Egypt wom Dermatol Soc. Vol. 5, No. I , 2008
Fig. 2(B). Striae rubra showing typical erythema
immediately following microdermabrasion treatment.
Treatment of striae distewith microdemuzbrasion:
a clinical and.qolecular study
,
I
L
I
A
Fig. Z(C). Treated striae 6 weeks after brdting
rnicrodermabrasion.
DISCUSSION
controlled study, 0.025% tretinoin cream
was ineffective in the treatment of striae
rubra and alba. (8) However, topical 0.1%
tretinoin was found to improve the clinical
appearance of early erythematous striae. ("J5)
In addition, striae alba were improved with
topical therapy with 20% glycolic acid
combined with either 0.05% tretinoin or
10% L- ascorbic acid, 2% Zinc sulfate and
0.5% tyr~sine.(~) Various lasers have
recently been reported as effective treatment
modalities for striae distensae, but
pigmentary alterations are a major concern
to the darker skin type. Jimenez et al,
reported that the 585- nm pulsed dye laser
might help to improve striae rubra but had
no effect on striae alba. (I1) Moreover, post
inflammatory hyperpigmentation was a
significant side effect in dark (IV-VI) skin
types. (l1~l2)In a recent study, the thermage
(a radiofrequency device for the lifting of the
face and neck) combined with pulsed dye
laser appeared to be an effective treatment
for striae distansae. (26) On the other hand,
Tay et al, (2006) found that the non ablative
1,450-nm diode laser was not useful in the
treatment of striae in patients with skin
types IV-VI. (I7) However, Intense- pulsed
light has been shown to improve striae alba
but PIH occurred in 40% of patients.(13) In
addition, the 308-nm excimer laser has been
shown to temporarily repigment striae by
increasing the number of melanocytes but
without improving the atrophy. 14-16
Microdermabrasion, a popular method of
superficial skin resurfacing with beneficial
effect in scarring(18) and photodamage (27)
would also be expected to improve striae
being dermal scars associated
with
epidermal atrophy. In this study, 50% of
patients with striae got good to excellent
(more than 50%) improvement while the
remaining 50% got mild to moderate (up to
50%) improvement compared to untreated
controls12
weeks
after
starting
5
microdermabrasion treatments at weekly
intervals. Striae rubra showed more
significant improvement than striae alba.
There was no significant difference' in the
degree of improvement in different (11-IV )
skin types. Complications were minimal and
limited
to
post
inflammatory
hyperpigmentation that occurred in 20 %
and transient erythema in 25% which was
well accepted by the patients. Eighty percent
of ' the studied patients were satisfied with
treatment. Mahuzier in his text book on
microdermabrasion(28)stated that
10-20
sessions of microdermabrasion at an interval
J Egypt wom Dermatol Soc. Vol. 5, No. 1,2008
Amany M. Abdel-Lltij-M.D.
and Amul S. Elbendui-y, M.D.
of not less than one month , each session
resulting in bleeding points, provide
satisfactory improvement in striae distensae.
Moreover, histological examination of the
striae after microdermabrasion treatment
showed epidermal thickening and more
collagen and elastic fibers in the dermis.28
In the current study, there was upregulated
type I procollagen a 1 mRNA expression in
treated striae being measured at 6 weeks
after starting microdermabrasion treatment.
This might indicate a stimulatory effect of
microdermabrasion on collagen formation
with
subsequent
dermal
remodeling
accounting for the therapeutic benefit. It has
been suggested based on histologic studies
that the beneficial effects noted with
microdermabrasion
for
scars
and
photodamage result from new collagen and
elastin production in the dermis.(29).
Karimipour et al,"" in their study on the
molecular alterations in normal skin
following rnicrodermabrasion, found that
mean increases in the study population of
type 1 procollgen mRNA and protein failed
to reach statistical significance after a single
microdermabrasion
treatment
(measurements were made on days 1,
2,3,4,7,10,14, and 16, post treatment).
However, 2 of 11 subjects studied did
demonstrate increased type I procollagen
gene expression (2.9-, 3.1-fold) 14 days
after a single microdermabrasion treatment.
Type I11 procollagen and tropoelstin mRNA
and protein levels did not appear to change
in that study.(22) We can speculate that
repeating microdermabrasion treatment can
make the stimulatory effect on type I
procollagen gene expression manifest
contributing to the increased mean type I
procollagen a1 mRNA levels observed in
our study. Emerging evidence indicates that
internal or externally applied mechanical
tension on the skin can substantially alter the
activity of key pathways that regulate
connective tissue homeostasis.(30)In a recent
study,(31) the abrasive component together
with
the
negative
pressure
of
microdermabrasion were necessary for
stimulating expression of key genes
involved in dermal remodeling. There was
J Egypt worn Dermatol Soc. Vol. 5, No. 1, 2008
significant increases in gene expression of
the c-Jun component of activator protein- 1,
interleukin 1 p, tumor necrosis factor - a,
matrix
metalloproteinases
(
MMP- 1,
MMP-3, MMP-9 ) in normal skin treated
micr~dermabrasion.(~l)
with
Microdermabrasion treatment appeared to
set in motion a cascade of molecular events
capable of causing dermal remodeling and
repair.(22) Studies
on
the
use o f
rnicrodermabrasion in treatment of striae are
lacking. There remains a major disparity
between
the
popularity
of
microdermabrasion in the public sector and
cohesive and comprehensive scientific data
documenting the efficacy of the procedure.
(32)
In conclusion, rnicrodermabrasion is
effective, well tolerated, and safe for
treating striae distensae having more
beneficial effect on striae rubra than striae
alba with ability to upregulate
type I
procollagen mRNA expression involved in
dermal matrix remodeling. Reappraisal of
this potentially useful procedure points
toward a need for well-designed clinical
trials and studies with a long follow-up
based on objective assessment parameters. A
larger study may be needed to demonstrate
any additional benefit including the
influence of microdermabrasion on different
aspects of dermal remodeling and repair.
Further studies are also needed to determine
the optimum number of treatment sessions
and the suitable intervals between treatments
beside the possibility of enhancing its effect
by combining microdermabrasion with other
treatments as topical tretinoin or glycolic
acid in treating striae.
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J Egypt wom Derrnatol Soc. Vol. 5, No. I , 2008