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Damage and Recovery of Skin Barrier Function After Glycolic Acid Chemical Peeling and Crystal Microdermabrasion
Abstract
Superficial chemical peeling and microdermabrasion have become increasingly popular methods for producing facial rejuvenation. However, there are few studies reporting the skin barrier function changes after these procedures.
To evaluate objectively the degree of damage visually and the time needed for the skin barrier function to recover after glycolic acid peeling and aluminum oxide crystal microdermabrasion using noninvasive bioengineering methods.
Superficial chemical peeling using 30%, 50%, and 70% glycolic acid and aluminum oxide crystal microdermabrasion were used on the volar forearm of 13 healthy women. The skin response was measured by a visual observation and using an evaporimeter, corneometer, and colorimeter before and after peeling at set time intervals.
Both glycolic acid peeling and aluminum oxide crystal microdermabrasion induced significant damage to the skin barrier function immediately after the procedure, and the degree of damage was less severe after the aluminum oxide crystal microdermabrasion compared with glycolic acid peeling. The damaged skin barrier function had recovered within 24 hours after both procedures. The degree of erythema induction was less severe after the aluminum oxide crystal microdermabrasion compared with the glycolic acid peeling procedure. The degree of erythema induced after the glycolic acid peeling procedure was not proportional to the peeling solution concentration used. The erythema subsided within 1 day after the aluminum oxide crystal microdermabrasion procedure and within 4 days after the glycolic acid peeling procedure.
These results suggest that the skin barrier function is damaged after the glycolic acid peeling and aluminum oxide crystal microdermabrasion procedure but recovers within 1 to 4 days. Therefore, repeating the superficial peeling procedure at 2-week intervals will allow sufficient time for the damaged skin to recover its barrier function.
... Stratum corneum removal can be done by tape stripping, but the procedure is time consuming and requires expert technique [15] Ablation utilizes energy generated by lasers or heating elements to remove the stratum corneum [51]. Abrasion uses sandpaper or pressurized particles, such as microdermabrasion, to remove the stratum corneum [7, 8, 12, 13, 15, 54]. The advantage to using abrasion is that it is quick and painless, and that microdermabrasion is already approved by the FDA for other applications. ...
... Although previous studies have been successful in completely removing the stratum corneum using microdermabrasion, the recovery of the barrier after complete removal has yet to be examined. A previous study was conducted to study barrier recovery in humans after microdermabrasion treatment using transepidermal water loss and it was shown that the barrier recovered one day after treatment [54]. It was not indicated if the stratum corneum was completely removed. ...
... Several studies have investigated the recovery of the stratum corneum after disruption with microdermabrasion, chemical treatment, and microneedles. The skin has been shown to heal within between 1 to 2 days following microdermabrasion treatment, with no occlusion, in humans as measured by transepidermal water loss measurements [54, 75]. The microdermabrasion pressure used for the experiment was higher than used for this study, but there was no indication of exposure time and the degree of stratum corneum removal. ...
The skin serves as a semi-permeable barrier that protects the body from pathogens and water loss. The stratum corneum, the upper 10-15 µm layer of skin, is the primary barrier layer. Due to its structure, only drugs that are lipophilic and with a low molecular weight (<500 Da) can penetrate intact skin. This study examines the use of microdermabrasion as a method of removing the stratum corneum to increase the skin's permeability to hydrophilic molecules, proteins, and vaccines. Microdermabrasion is a FDA-approved cosmetic skin resurfacing procedure that removes the stratum by bombarding it with abrasive particles under vacuum. The aims of this thesis are focused on optimizing the microdermabrasion conditions that will selectively remove stratum corneum, evaluating the transport of different sized molecules through abraded skin in vitro, examining drug efficacy in vivo by delivering insulin to diabetic rats, and examining the rate of skin healing after treatment. Microdermabrasion can be used as a non-invasive transdermal drug technique to safely remove stratum corneum to make the skin more permeable to waters soluble drugs and proteins.
... 19 Three minutes of a single application of 50% GA resulted in a 24-h persistent increase in transepidermal water loss. 20 Some studies have also been performed on the effect of GA application on topical steroid. A combination of GA and betamethasone produces better therapeutic effects than betamethasone alone, 21 and 3 min of occlusive application of 10% GA enhances the vasoconstriction effects of 0.05% clobetasole propionate. ...
... Song et al . 20 found that the application of 50% GA for 3 min on the volar site of forearm skin led to an increase in transepidermal water loss, a manifestation of decreasing skin barrier function. Decreasing skin barrier function increases the percutaneous absorption of topical drug and accelerates the onset of drug action. ...
... The results are once again similar to those of Song et al . 20 and Koppel et al . 8 The conclusion from our study is that the application of 50% GA for 4 min prior to the administration of EMLA is a simple and safe procedure. ...
EMLA has a slow onset due to its limited percutaneous absorption into an intact skin, while Glycolic acid (GA) has been known to have the capability of disrupting the skin barrier function. To the best of our knowledge, the effect of 50% GA on the percutaneous absorption of EMLA has not been studied previously.
The study used a two-step randomized double blind controlled trial involving 20 healthy subjects each. The first step compared the pain intensity upon applying GA and placebo for 4 minutes prior to EMLA occlusive application over time. Based on findings made in the first step, second step observation focused on the effect of occlusion on EMLA percutaneous absorption after GA application in minute 30 and 45. A second of 20 mA electrofulguration induced the pain, while modified Verbal Rating Scale (VRS) measured the pain intensity.
Significant VRS difference (P < 0.05) between GA and placebo group was found in minute 15, 20, 30 and 45. However, no significant VRS difference was found after minute 60 (P = 0.420). Adequate cutaneous analgesia was achieved in minute 30 in the treatment (GA) group and in minute 45 in the placebo. There was no significant VRS difference between the occlusive and non-occlusive group in minute 30 (P = 0.214) and minute 45 (P = 0.309).
Administering 50% GA prior to EMLA application enhances percutaneous absorption of EMLA, which accelerates the onset of adequate cutaneous analgesia, even without using an occlusive dressing.
... The recovery period after stratum corneum removal is dependent on the degree of disruption, but the recovery response leads to restoration of the barrier function within hours to days [33][34][35][36][37]. Furthermore, complete stratum corneum removal requires over 70 tape strips [38,39]. ...
... This observation possibly reflects the saturation uptake capacity of the stratum corneum for the formulation we used here. Alternatively, it may be possible that side effects of repeated tape stripping of the same site in 3-6 days interval cannot be excluded, despite a rapid recovery after stratum corneum removal within a few days [33][34][35][36][37]. Nevertheless, we provided additional information on clearance (Table 1). ...
Ascorbic acid (AA) is a water-soluble vitamin that is found at high concentrations in normal skin. The important and well-known benefits of using AA in skin health include the stimulation of collagen synthesis and the assistance of protection against photo-oxidative damages. To maintain stability and improve drug delivery to the active site, a variety of AA derivatives have been chemically synthesized. Among these compounds, we focus here on a lipophilic derivative, 3-O-cetyl ascorbic acid (3-CetylAA), which remains poorly characterized for cosmetic applications. Uptake analysis in three healthy human volunteers’ skin was conducted using a serial tape-stripping technique detecting 3-CetylAA (on average, 128 ± 27 pmol per µg) in the stratum corneum after a 5-h topical treatment when treated with 25 mM 3-CetylAA-containing cream for 13 days twice daily and continuously. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) imaging of vertical cryosections of pig skin revealed the presence of 3-CetylAA in the epidermal layer after topical treatment with 3-CetylAA-containing cream. In sun-exposed human skin, 3-CetylAA improved the texture after treatment with 25 mM 3-CetylAA-containing cream for 4 weeks or more when used twice daily or continuously. An in vitro transformation assay using BALB/c 3T3 A31-1-1 cells demonstrated that 10 µM 3-CetylAA, which is the same concentration exhibited in vitro biological activities in another lipophilic AA derivative, 2-O-octadecyl ascorbic acid, was non-carcinogenic and did not potentiate the UVC-induced transformation frequency when applied for 3 days after UVC irradiation. These results demonstrate that 3-CetylAA is a promising candidate as a lipophilic derivative of AA for cosmetic purposes.
... Literature evidence is reflected by a number of clinical studies which report the clinical efficacy of superficial peels for improvement of post acne hyperpigmented scars in dark skin types [9,11,14,[16][17][18][19][20][21]. ...
... Enzymatic degradation at corneocyte surface facilitates detachment and peeling and subsequent regeneration evokes a thin stratum corneum and compact epidermis and dispersion of epidermal melanin. The dermal action in GA manifests due to its rapid penetration through horny layer by its small molecular size, By its dermal action GA improves quality of elastin and decreases density of collagen [11,16]. A regularized keratin layer and good hydration and its pigment reducing action makes GA a popular peel of choice in post acne phase due to its multi-modality action. ...
... 8. Help deal with areas of skin that have too much or too little pigment. 9. Increase scalp and hair health and strength resulting in faster hair growth, increased hair follicle health and activity, a fuller head of hair, and decreased damage from hair coloring, curlers, perms, blow dryers, etc. ...
... For example skin resurfacing procedures with the carbon dioxide (CO 2 ) laser, chemical peels, and dermabrasion have significant complication profiles including the loss of skin elasticity. 1,2,3,4,5,6,7,8,9,10,11,12,13 As do the use of various "fillers" such as the resorbable heterologous fillers (bovine collagen, acid hyaluronique), autologous fillers (lipofilling, dermis-fat graft), biodegradable fillers (New-Fill), and permanent fillers (silicone, Artecoll, Evolution, Aquamid, DermaLive, DermaDeep, Bioplastique, Paraffin). 14 Also cosmetic surgery, from Botox® injections to Liposucton, can result in significant complications and even death. ...
This performance is about the materialization of the performer's thoughts and feelings on the stage. In the performance, imagination becomes spatial. The stage is a place for the appearance of the invisible. Yasu Ohashi says: "The actors aim at our senses, our body, and our unconscious and not at our intellect. Their gestures try to envision the invisible world."
... According to Yokomizo et al. [31], glycolic acid can induce epidermolysis for a period ranging from three to seven minutes. Song et al. [32] evaluated the effects of superficial chemical peeling using 50% glycolic acid, applied to the forearm of a sample of volunteers for a duration of three minutes. The authors reported an increase in transepidermal water loss (TEWL) in the first hours following the procedure, and noted the presence of erythema up to 3 days later. ...
Plant-derived substances such as curcumin and trans-resveratrol, both of which have anti-inflammatory properties, may have a beneficial effect on human skin. The present study analyzed the effects of topical formulations containing curcumin or trans-resveratrol on the recovery and rejuvenation of skin after chemical peeling. The study was performed on rats, randomly divided into seven groups of six animals each. Superficial peeling was performed using a 50% glycolic acid gel, which was applied to the dorsal region of each animal. Rats were then treated with the experimental formulations for 15 days. On the sixteenth day, skin samples were taken and mounted on slides for histological analysis. Statistical analysis showed that the formulation containing trans-resveratrol led to increased dermal and epidermal thickness, while the formulation containing curcumin had no effects on epidermal thickness. The increased epidermal thickness may reflect greater skin vitality, although this was not directly evaluated. The increase in dermal thickness may be attributed to greater collagen production, which may increase skin firmness and elasticity, and lead to skin rejuvenation as well as wrinkle reduction. Formulations containing curcumin or trans-resveratrol may have potential for the topical treatment after peeling and of sensitive skin, in addition to being used for their antiaging properties.
... In contrary to the previous report, Song et al. [23] reported that glycolic acid application caused increased sensitivity to UVA and UVB light, thus cause erythema. ...
Acne vulgaris is a chronic inflammatory skin disease; it's one of the most common skin disorders and affects mainly adolescents and young adults. Keratolytic agents are widely used in treatment of acne from several years. In this study we aimed to evaluate and compare the cutaneous response of different keratolytic agents in management of acne vulgaris. Ninety patients were selected among those attending the outpatient dermatology clinic in ADDwadmi hospital during the period from October 2015 to February 2016. The selected patients had different forms of acne vulgaris, papulo-pustular, comedonal and post acne scar. Three types of keratolytic agents were used, glycolic acid 50%, salicylic acid 20% and jessner solution. In papulopustular lesions, the three agents were effective with non-significant difference between them; however, there was more excellent results with jessner solution (70 % of patients) then glycolic acid (50%) and lastly salicylic acid (40%). According to the clinical efficacy of used keratolytic agents in comedonal lesions , all lines were found to be effective and there was non-significant difference between the 3 studied groups, however there was more excellent results with salicylic acid (80%) then glycolic acid (60%) and lastly Jessner solution (50%). According to the clinical efficacy of all keratolytic agents in acne scar lesions, there was significant difference between the 3 studied groups. Both jessner and salicylic acid were non effective, however glycolic acid was moderately effective (30% showed excellent results and 40% showed good results). Minimal complications were noticed with all the agents used. More erythema was recorded with jessner solution. However there was significant difference between all keratolytic agents as regards the incidence of visible exfoliation where glycolic acid showed least visible exfoliation (only 40% of cases) followed by jessner solution (66.7%) and lastly salicylic acid (80%).
... The skin barrier function is damaged 138 after the glycolic acid peeling and aluminium oxide crystal microdermabrasion procedure, but recovers within 1-4 days. 139 Therefore, repeating the superficial peeling procedure at 2-week intervals will allow sufficient time for the damaged skin to recover its barrier function. ...
Within their first days of life, newborns’ skin undergoes various adaptation processes needed to accommodate the transition from the wet uterine environment to the dry atmosphere. The skin of newborns and infants is considered as a physiological fragile skin, a skin with lower resistance to aggressions. Fragile skin is divided into four categories up to its origin: physiological fragile skin (age, location), pathological fragile skin (acute and chronic), circumstantial fragile skin (due to environmental extrinsic factors or intrinsic factors such as stress) and iatrogenic fragile skin.
Extensive research of the past 10 years have proven evidence that at birth albeit showing a nearly perfect appearance, newborn skin is structurally and functionally immature compared to adult skin undergoing a physiological maturation process after birth at least throughout the first year of life. This article is an overview of all known data about fragility of epidermis in ‘fragile populations’: newborns, children and adolescents. It includes the recent pathological, pathophysiological and clinical data about fragility of epidermis in various dermatological diseases, such as atopic dermatitis, acne, rosacea, contact dermatitis, irritative dermatitis and focus on UV protection.
... The safety of this ablative approach should be first approved for extensive application. Song et al. [77] reported that the increased TEWL value by microdermabrasion (530 mm Hg) returned to the baseline within 1 day in the volar forearms of human subjects. Recently, Andrews et al. [78] measured the skin-barrier recovery of hairless Guinea pigs after SC removal by microdermabrasion with a settled vacuum pressure (40 kPa) for drug-permeation enhancement. ...
Physical ablation can be an effective drug-permeation-enhancement strategy for promoting drug delivery into or across the skin. The controlled ablation of the stratum corneum (SC), the predominant barrier for drug absorption, is achieved by ablative techniques incorporating the use of lasers, microneedles, microdermabrasion, and radiofrequency. It has been demonstrated that ablative approaches used for enhancing drug transport provide some advantages, including increased bioavailability, fast treatment time, and quick recovery of SC integrity. In recent years the concept of using ablative techniques to treat skin has attracted increasing attention. This review describes recent developments using skin-ablative approaches for drug-permeation enhancement. This review systematically introduces the concepts and enhancement mechanisms of various physical ablative methods, highlighting the potential of these techniques for greatly increasing drug absorption via the skin. In this review, we principally focus on the small-molecule drugs approved by the US FDA for clinical use. The macromolecules and nanoparticles as the model permeants are not the focus of this review since they have not until recently been extensively applicable in clinical situations. Finally, future developments and trends are anticipated.
... In chemical peeling, acids such as glycol acid (hydroxyacetic acid) have been applied for removal of old cuticle, reforming to normal peel by natural healing [1]. However, in abrasion of cuticle by acid, excess calcium ion is generated by dissolving protein in cell wall of peel, as a result, removing dead cell. ...
... Afortunadamente, los procedimientos de quimioexfoliación cada vez son más refinados, con mayor perfil de seguridad y con evidencias más fundamentadas, por lo que el usuario consigue su objetivo de satisfacción y mayor comodidad. 16,17 En la bibliografía consultada se insiste en lesiones tipo pénfigo eritematoso inducidas por daño térmico, luz solar, concentración-profundidad del quimioexfoliante utilizado o modalidad de luz artificial usada (terapia fotodinámica). ...
RESUMEN Se comunica el caso de dos pacientes con dermatosis localizadas en la piel cabelluda y el dorso nasal, respectivamente. En ambas historias médicas existía el antecedente intervencionista de quimioexfoliación aplicada semanas antes. Las erosiones y placas costrosas hicieron considerar el diagnóstico inicial de heliodermatosis y dermatitis seborreica, respectivamente. Por histopatología e inmunofluo-rescencia directa se corroboró pénfigo eritematoso. Sugerimos que esta enfermedad se considere formal contraindicación o antecedente de evolución agravada luego de un procedimiento quimioexfoliativo. Palabras clave: pénfigo eritematoso, quimioexfoliación, procedmientos intervencionistas. ABSTRACT We report the case of two patients with dermatoses localized in scalp and nose, respectively. In both cases, the patients had history of interventional procedures such as chemical peeling weeks before. Erosions and recalcitrant plaques with flakes and crusts in treated places made us consider the initial diagnosis of each patient: heliodermatosis and seborrheic dermatosis, respectively. Through histopathology and direct immunofluorescence we corroborated the pemphigus erythematosus. We suggest considering this entity as a formal contraindication or history of aggravated evolution after a chemical peeling.
... The MCI is currently evaluating proposals to start 500 new medical colleges over the next 5 years. 6 It should strictly enforce the idea of setting up new medical colleges predominantly in rural areas. ...
... Stratum corneum removal can be done by tape stripping, but the procedure is time consuming and requires expert technique (Fujimoto et al., 2005) Ablation utilizes energy generated by lasers or heating elements to remove the stratum corneum (Banga, 2009). Abrasion uses sandpaper or pressurized particles, such as microdermabrasion, to remove the stratum corneum (Fang et al., 2004;Fujimoto et al., 2005;Gill et al., 2009;Lee et al., 2003;Lee et al., 2006;Song et al., 2004). The advantage to using abrasion is that it is quick and painless, and that microdermabrasion is already approved by the FDA for other applications. ...
Microdermabrasion has been shown to increase skin permeability for transdermal drug delivery by damaging or removing skin's outer layer, stratum corneum. However, relationships between microdermabrasion parameters and effects on the stratum corneum barrier have not been developed. In this study, we determined the effect of microdermabrasion crystal flow rate, time, and suction pressure applied in both static and dynamic modes on the extent of stratum corneum removal from excised porcine skin. In addition to controlling the depth of tissue removal by microdermabrasion parameters, we also controlled the area of tissue removal by applying a metal mask patterned with 125- or 250-μm holes to selectively expose small spots of tissue to microdermabrasion. We found that the extent of stratum corneum removal depended strongly on the crystal flow rate and exposure time and only weakly on pressure or static/dynamic mode operation. Masking the skin was effective to localize stratum corneum removal to exposed sites. Overall, this study demonstrates that optimized microdermabrasion in combination with a mask can be used to selectively remove stratum corneum with three-dimensional control, which is important to translating this technique into a novel method of transdermal drug delivery.
... 89,90,92 Glycolic acid (GA), found in sugarcane, is a naturally occurring alpha-hydroxy acid (AHA) that induces epidermolysis, disperses basal layer melanin, and increases dermal collagen synthesis. 90,93 GA concentrations range from 20 to 70%, and neutralization with water or sodium bicarbonate is required to terminate the peel. Burns et al 94 conducted a 22-week clinical study of 16 African-American patients with Fitzpatrick skin types IV to VI and facial PIH. ...
Postinflammatory hyperpigmentation is a common sequelae of inflammatory dermatoses that tends to affect darker skinned patients with greater frequency and severity. Epidemiological studies show that dyschromias, including postinflammatory hyperpigmentation, are among the most common reasons darker racial/ethnic groups seek the care of a dermatologist. The treatment of postinflammatory hyperpigmentation should be started early to help hasten its resolution and begins with management of the initial inflammatory condition. First-line therapy typically consists of topical depigmenting agents in addition to photoprotection including a sunscreen. Topical tyrosinase inhibitors, such as hydroquinone, azelaic acid, kojic acid, arbutin, and certain licorice extracts, can effectively lighten areas of hypermelanosis. Other depigmenting agents include retinoids, mequinol, ascorbic acid, niacinamide, N-acetyl glucosamine, and soy with a number of emerging therapies on the horizon. Topical therapy is typically effective for epidermal postinflammatory hyperpigmentation; however, certain procedures, such as chemical peeling and laser therapy, may help treat recalcitrant hyperpigmentation. It is also important to use caution with all of the above treatments to prevent irritation and worsening of postinflammatory hyperpigmentation.
... Following microdermabrasion, Coimbra et al. [8] reported vascular ectasia, dense mononuclear inflammatory cells infiltrate, an increase in the epidermal thickness and organized collagen in the treated skin relative to the control group. These findings suggest that the repetitive intraepidermal and dermal injuries associated with microdermabrasion may stimulate fibroblast proliferation and collagen production, leading to new collagen deposition in the dermis [9]. ...
Post-inflammatory hyperpigmentation (PIH) is a reactive hypermelanosis, profoundly common in the Asian skin. The post-acne sequelae may have profound effects on the patients’ mental status, sometimes even more than the acne itself, as they are long lasting and sometimes treatment refractory. PIH occurs secondary to release of inflammatory mediators such as prostaglandins and interleukins in acne which stimulate melanogenesis. There are a multitude of therapeutic modalities available for the treatment of PIH associated with acne. Treating acne and PIH simultaneously would be a logical approach. Epidermal PIH usually responds to topical skin lightening agents which are the first line in these cases. Patients refractory to topical and oral treatment modalities usually have dermal PIH and may be offered interventional therapies. These therapies can be utilized simultaneously along with conventional therapies to hasten up the results, as combination treatment works synergistically by multipronged action at different pathways of etiopathogenesis. The patients with dermal PIH refractory to standard treatment may require other adjunctive therapies such as chemical peels, PRP, and lasers. This review provides an insight into rational and holistic approach to the management of the underlying acne, early customized treatment along with correction of underlying nutritional deficiencies, and lifestyle modifications in effective treatment of PIH.
Introduction:
The number of dermatological or cosmetic procedures carried out has continuously increased over the last decades. Almost all may cause transient local skin reactions such as erythema, blistering, crusts, scaling, hypo- or hyper-pigmentation, or haemorrhagic lesions. One issue of dermatological procedures is the down time, during which patients need to hide their skin, due to these local reactions.
Aim:
to provide dermatologists with easy-to-follow recommendations for the right timing of use of corrective make-up for patients who have undergone or who plan to undergo dermatological procedures, according to the invasiveness of the dermatological procedure chosen.
Methodology:
A group of experts in dermatological procedures met in 2019 and at the beginning of 2020 to discuss the different procedures, their local reactions and down time, and the opportunities to use specific corrective make-up in order to hide these transient reactions.
Results:
As a result of the discussions, the experts proposed a tabulated algorithm of use based on a classification of the different dermatological procedures according to their invasiveness and recommended timing of the first post-procedure corrective make-up application.
Conclusion:
Corrective make-up may be considered as a complement to certain dermatological procedures in order to minimise down time. However, its use is conditioned by the correct understanding of skin barrier alteration and recovery time. The proposed algorithm of use of corrective makeup after procedures may help the practioner to indicate his patient the right moment for applying corrective makeup in order to avoid local tolerance issues and post-procedure complications.
The penetration of optical clearing agents (OCAs) is restricted by the natural barrier function of the stratum corneum (SC) of the skin, which can be breached by physical and chemical methods to enhance the transcutaneous delivery of OCAs. To breach the barrier function of SC, we carried out the in vivo experimental study to enhance the optical clearing effect of PEG-400 by laser irradiation in conjunction with a chemical penetration enhancer thiazone. We compared the reflectance spectra of skin without laser irradiation or thiazone. Mono-treatment of thiazone could not significantly enhance the optical clearing efficacy of the skin. After 60 min, the reflectance spectrum decreased by only approximately 10%. With the combined treatment, the reflectance spectrum decreased by approximately 30% after 10 min. Subsequently, the effect of laser dose on the enhancement of optical clearing efficacy was studied. The optimal irradiation dose was determined. The reflectance of skins irradiated by a laser dose at 0.7 J/cm2 decreased by approximately 10% and were 20% lower than those at 0.5 and 0.9 J/cm2. The laser at 0.5 J/cm2 could not damage the SC completely, whereas the laser at 0.9 J/cm2 influenced the epidermis and dermis; thus, the reflectance of skin samples irradiated by 0.9 J/cm2 did not decrease.
An understanding of the factors that influence the percutaneous absorption of drugs, diagnostic agents and cosmetics is essential if the topical delivery route is to reach its full potential. Considerable progress has been made in the use of optimised formulations and advanced delivery systems, such as nanoparticulate carriers, to penetrate the skin barrier. However, in this chapter we will examine the more fundamental question of how a penetrant interacts with the skin barrier, and how the properties of the molecule and the skin can affect this. We firstly discuss the inherent physicochemical properties of a molecule and how these can be used to predict skin permeation rates and targeting to particular routes and sites. In addition to penetrant properties, skin properties determined by the degree of hydration, age, gender or body site also influence rates of percutaneous absorption. Other ways in which the skin barrier performance may be affected include prior skin treatments with cosmetics, depilatories, peeling agents or insect repellents, as well as burns and intrinsic defects. Finally, we discuss some ways in which the barrier function of the skin may be enhanced, in order to protect against unwanted penetration of irritants and toxic materials.
Background:
Microdermabrasion and chemical peeling are popular, inexpensive, and safe methods for treatment of some skin disorders and to rejuvenate skin.
Objectives:
To study the alterations of the dermal connective tissue following salicylic acid peeling and microdermabrasion.
Methods:
Twenty patients were participated in our study. All participants underwent facial salicylic acid 30% peel or microdermabrasion (10 cases in each group) weekly for 6 weeks. Punch biopsies were obtained from the clinically normal skin of the right postauricular region 1 week before treatment (control group). Other punch skin biopsies were obtained 1 week after the end of the treatments from the left postauricular area. This region was treated in a similar way to the adjacent lesional skin (treated group). We used routine histological techniques (H&E stain), special stains (Masson trichrome and orcein stains), and image analyzer to study the alterations of the dermal connective tissues.
Results:
Our study demonstrates variations in the morphological changes between the control and the treated groups, and between chemical peels and microdermabrasion. Both salicylic acid 30% and microdermabrasion were associated with thickened epidermal layer, shallow dermal papillae, dense collagen, and elastic fibers. There was a significant increase among those treated sites vs control regarding epidermal thickness and collagen thickness. Also, there was a highly statistically significant increase among those treated with salicylic acid vs microdermabrasion regarding the epidermal, collagen, and elastin thickness.
Conclusions:
Both methods stimulate the repair process. The mechanisms underlying these variations are open for further investigations.
Microdermabrasion is a popular technique for superficial resurfacing of the skin [1]. It involves the propulsion of abrasive microcrystals on to the treatment area in short strokes using a special handpiece. The handset simultaneously vacuums away the used abrasive particles and skin debris. The speed of the particles (and the vacuum suction) can be adjusted by the operator to control the volume of particles bombarding the skin. Other factors influencing the intensity of the treatment are the speed of movement of the handpiece and the number of times it is passed over the skin. An increased depth of microdermabrasion is achieved when the handpiece is moved slowly and repeatedly over a specific site [2]. Overall, the technique is considered to be minimally invasive with few complications [2]. Particle-free microdermabrasion units have become extremely popular. Such units utilize a disposable or reusable diamond wand to induce abrasion. Numerous microdermabrasion units are available globally.
Objective:
In vivo changes in skin barrier function after chemical peeling with alpha hydroxyacids (AHAs) have been previously reported. However, the additional effects of physical treatment with chemical agents on skin barrier function have not been adequately studied. This study measured the degree of acute skin damage and the time required for skin barrier repair using noninvasive bioengineering methods in vivo with human skin to investigate the additional effect of a 4% AHA chemical jet accelerated at supersonic velocities.
Methods:
Thirteen female subjects (average age: 29.54 ± 4.86 years) participated in this study. The faces of the subjects were divided in half according to the block randomization design and were then assigned to receive AHA peeling alone or AHA peeling combined with pneumatic pressure on each side of the face. Transepidermal water loss (TEWL), skin color, and skin blood flow were evaluated at baseline and at 30 min, 2, 5 and 7 days after treatment RESULTS: The TEWL and skin blood flow were significantly increased after 30 minutes in chemodermabrasion compared with chemical peeling alone (p<0.05). The TEWL and skin blood flow recovered to baseline after 2 days, and TEWL was significantly decreased at 7 days compared with chemical peeling alone (p<0.05).
Conclusions:
Chemodermabrasion can temporarily impair skin barriers, but it is estimated that it can enhance the skin barrier function after 7 days compared to the use of a chemical agent alone. In addition, chemodermabrasion has a more effective impact in the dermis and relatively preserves the skin barrier. This article is protected by copyright. All rights reserved.
Objective
Alpha-hydroxy acids (AHA) have been recognized as commonly used therapy for acne. Our studies examined whether an additional effect of physical treatment using chemical peeling combined with negative pressure and compared with AHA treatment only occurs in acne prone subjects.Methods
The chemical peeling agent used 4% of an AHA solution (mixture of 1000 mL of carbonated water, 20 mL of glycolic acid, and 20 mL of lactic acid). All subjects’ faces were randomly divided into test and control groups. The test group was treated with chemical peeling combined with a physical effect, and the control group applied chemical peeling alone.For the 23 healthy females (average age: 30.17±5.06 yr), we measured sebum output level by light transmission, pore area and number by optical image analyzer, and comedone counting before treatment, and at 1, 2, and 4 weeks after a single treatment.ResultsCompared to the before treatment, whiteheads and blackheads were significantly decreased at 1, 2, and 4 weeks in the test group (p<0.05), but for the control group, whiteheads and blackheads showed a tendency to decrease at 1, 2, and 4 weeks. Also at 1 week, whiteheads and blackheads of the test group significantly decreased compared to the control group (p<0.05).Pore area and number significantly decreased at 1 week (p<0.05), and the sebum output level was significantly decreased at 4 weeks (p<0.05) only in the test group, which did not show any significant group difference for individual parameters.Conclusion4% AHA solution combined with a physical effect had rapidly improving effects on whiteheads and blackheads synergistically. Combined physical therapy may have more impact of pore size and seborrhea.This article is protected by copyright. All rights reserved.
Background:
Many comparative studies of chemical peeling and dermabrasion have been reported. However, rare basic scientific data about the immediate effects after combined treatment with chemical peeling and dermabrasion have been confirmed.
Objectives:
The aim of this study is to evaluate the effect of the application of physical abrasion in combination with chemical peels.
Materials and methods:
Three pigs were treated with physical abrasion using a water jet device in combination with an α-hydroxy acid solution, and the skin samples of the control received chemical peeling solution alone. The levels of growth factors and neuropeptides were measured with a multiplex immunoassay.
Result:
Skin treated with physical dermabrasion combined with chemical peeling showed prominent detachment and swelling of the stratum corneum (SC), and fluid collection in the hair follicles. The mean cell count of CD34 positive fibroblasts and mast cells, levels of epidermal growth factor, fibroblast growth factor-2, vascular endothelial growth factor, and neurotensin, were significantly increased in the tissue treated with physical abrasion combined with a chemical peeling agent, compared to the skin in the control.
Conclusion:
We concluded that physical dermabrasion combined with chemical peeling can be more effective than chemical peeling alone, for the approach through transfollicular routes.
Postinflammatory hyperpigmentation (PIH) is a reactive hypermelanosis and sequela of a variety of inflammatory skin conditions. PIH can have a negative impact on a patient's quality of life, particularly for darker-skinned patients. Studies show that dyschromias, including PIH, are one of the most common presenting complaints of darker-skinned racial ethnic groups when visiting a dermatologist. This is likely due to an increased production or deposition of melanin into the epidermis or dermis by labile melanocytes. A variety of endogenous or exogenous inflammatory conditions can culminate in PIH and typically most epidermal lesions will appear tan, brown, or dark brown while dermal hypermelanosis has a blue-gray discoloration.Depigmenting agents target different steps in the production of melanin, most commonly inhibiting tyrosinase. These agents include hydroquinone, azelaic acid, kojic acid, arbutin, and certain licorice (glycyrrhiza) extracts. Other agents include retinoids, mequinol, ascorbic acid (vitamin C), niacinamide, N-acetyl glucosamine, and soy, and these products depigment by different mechanisms. Certain procedures can also be effective in the treatment of PIH including chemical peeling and laser therapy. It is important to note that these same therapeutic modalities may also play a role in causing PIH. Lastly, those lesions that are not amenable to medical or surgical therapy may experience some improvement with cosmetic camouflage.
Here we examined the effect of human normal breast (NB) and breast cancer (BC) tissues in vitro after treatment with glycerol in conjunction with ultrasound (surgeonperformed, SP) by OCT for functional imaging to monitor. 60% glycerol (G) and SP was simultaneously applied for 5 min. Depth- and time-resolved profiles for OCT signal enhancement were presented. The results show that OCT imaging depth of breast tissues after treatment with 60% G in combined with SP more obviously improved than that after application of glycerol alone. The permeability coefficient of 60% glycerol in 60% G/NB, 60% G/BC, 60% G/SP/NB, and 60% G/SP/BC were (0.91±0.02)×10-5 cm/s, (3.22±0.09)×10-5 cm/s, (1.63±0.04)×10-5 cm/s, and (7.98±0.19)×10-5 cm/s, respectively. The permeability coefficient of glycerol in 60% G/SP/NB was 1.84-fold than that in 60% G/NB, but there was 2.54-fold on permeability coefficient comparing 60% G/SP/BC with that in 60% G/BC. The results from this study indicated that the permeability coefficient of glycerol not only in normal breast tissues, but also in breast cancer tissues after treatment with ultrasound is larger than that in tissues without ultrasound. (© 2010 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA)
Background:
Microdermabrasion is a widely performed skin rejuvenation procedure. It can partly ablate and homogenize the stratum corneum (SC) layers.
Objective:
The effect of microdermabrasion treatment on the skin permeation of hydrophilic and lipophilic drugs was examined in this study.
Methods:
5-Fluorouracil (5-FU) and clobetasol 17-propionate were used as the hydrophilic and lipophilic permeants, respectively. In vitro skin delivery using porcine skin and in vivo topical application employing nude mouse as the animal model were both used to examine the effect of microdermabrasion. The vacuum pressures used in this study (15-25 cmHg) were much lower than those used for therapeutic purposes.
Results:
The 5-FU permeation across microdermabrasion-treated skin was 8- to 24-fold higher than that across intact skin and depended on differences in treatment pressure and duration. An intensity of 15 cmHg for 10 seconds showed the greatest enhancement of 5-FU delivery via the skin. In contrast to the results for 5-FU, microdermabrasion reduced the skin permeation and deposition of topically applied clobetasol. The partitioning effect of clobetasol from the vehicle to the SC may have predominated this result. Microdermabrasion also enhanced the skin delivery of the hydrophilic 5-aminolevulinic acid (ALA). Confocal laser scanning microscopy (CLSM) of microdermabrasion-treated skin revealed intense red fluorescence of ALA-transformed protoporphyrin (PpIX) within the epidermis and upper dermis.
Conclusions:
Microdermabrasion can improve the skin permeation of hydrophilic molecules.
Microdermabrasion is widely used as a non-invasive cosmetic technique that has recently been adapted to selectively remove stratum corneum to increase skin permeability for transdermal drug delivery. This study measured the kinetics of skin barrier recovery after stratum corneum removal using microdermabrasion in hairless guinea pigs. The skin was abraded at two sites on each animal, one of which was allowed to recover under occlusion while the other remained non-occluded. Histological measurements showed that skin barrier properties to sulforhodamine B largely recovered within 12 h, and the stratum corneum appeared largely reformed within 24 h for both occluded and non-occluded skin. Skin electrical resistance measurements showed significant recovery of the skin barrier within 24 h. We conclude that transdermal drug delivery may occur for up to 12 h after microdermabrasion in guinea pigs; however, humans will probably have a longer recovery time due to expected slower skin healing rates.
Microdermabrasion (MDA) is one of the top five nonsurgical cosmetic procedures performed. It is a well-established technology with widespread applications in the cosmetic industry.
To investigate the effects of MDA on skin and delivery of cosmeceuticals.
The alternation of skin structure post-MDA was examined by histological sectioning and transepidermal water loss measurements. The effect of MDA treatment on skin permeation profiles of hydrophilic and lipophilic molecules was investigated by laser scanning confocal microscopy and in vitro permeation studies.
Confocal images indicated different absorption profiles and permeation depths for hydrophilic and lipophilic molecules. Microdermabrasion enhanced the transdermal delivery of nicotinamide, the model hydrophilic compound employed. On the other hand, permeation of retinol, the model lipophilic compound, did not improve after treatment with MDA. When treated with 20 passes, the skin recovered from MDA induced changes in 4 days.
Permeation of cosmeceuticals into skin was found to be affected by their lipophilicity. Application of skin care products post-MDA therapy may be promising to improve their dermal uptake.
Dark-skinned patients manifest the signs of skin aging differently than their fair-skinned counterparts in that the former exhibit more intrinsic facial aging, whereas the later shows more photodamage. Nevertheless, common cosmetic procedures can be used in skin of color to treat the signs of aging.
To provide updated clinical information on the use of cosmetic procedures for skin aging in darker phototypes for the safe treatment of this population.
A Medline literature search was performed for publications on the safety and efficacy of botulinum toxin, dermal fillers, chemical peels, laser and light-based devices, and microdermabrasion for the treatment of skin aging specifically in ethnic populations.
Similarly to light-skinned patients, botulinum toxin and dermal fillers provide fast, effective results in skin of color, with fewer complications than with traditional surgery and no downtime. More-invasive procedures, such as chemical peeling, laser resurfacing, and microdermabrasion, can also be effective, but it is important to exercise caution and remain within certain parameters given the greater risk of dyschromias in this population.
With the proper knowledge of how to treat aging skin of color, these patients can experience the benefits of cosmetic procedures while minimizing the risks.
Acne vulgaris is one of the most common conditions for which all patients, including those with skin of color (Fitzpatrick skin types IV-VI), seek dermatological care. The multifactorial pathogenesis of acne appears to be the same in ethnic patients as in Caucasians. However, there is controversy over whether certain skin biology characteristics, such as sebum production, differ in ethnic patients. Clinically, acne lesions can appear the same as those seen in Caucasians; however, histologically, all types of acne lesions in African Americans can be associated with intense inflammation including comedones, which can also have some degree of inflammation. It is the sequelae of the disease that are the distinguishing characteristics of acne in skin of color, namely postinflammatory hyperpigmentation and keloidal or hypertrophic scarring. Although the medical and surgical treatment options are the same, it is these features that should be kept in mind when designing a treatment regimen for acne in skin of color.
In this paper, we propose a new physical method in combination with mixed solution of thiazone and polyethylene glycol 400 (thiazone PEG 400 solution) penetration into tissue to assess the skin optical clearing. Four treatments were performed: (1) control group (C); (2) polyethylene glycol 400 (PEG400); (3) 0.25% thiazone (0.25%T); (4) 0.25% thiazone and 5-min ultrasound (0.25%T/SP). The diffuse reflectance spectra and imaging depth of human skin in vivo at different times were measured by spectroscopy and optical coherence tomography (OCT). The optical clearing efficacy of skin was qualitatively and quantitatively analyzed. The results showed that the diffuse reflectance at 540 nm of samples at 10 min after being treated by 0.25%T/SP decreased by approximately 15.51%, whereas, 0.46%, 4.73% and 5.75% were received in C, PEG400 and 0.25%T, respectively. And at 60 min, the decrease in diffuse reflectance of samples in 0.25%T/SP is about 2.22-fold, 1.20-fold compared with that of the samples in PEG 400 and 0.25%T, at 540 nm, respectively. Simultaneously, 0.25%T/SP results in 41.33% increase in OCT 1/e light penetration depth after 60 min. There was a significant difference in the optical clearing effect on skin between ultrasound-mixed solution of thiazone in combination with PEG 400 and the mixed solution (P < 0.05).
Microdermabrasion is a popular method for facial rejuvenation and is performed worldwide. Despite its extensive usage, there are few publications on skin barrier change after microdermabrasion and none concerning diamond microdermabrasion. Our object was to see changes in transepidermal water loss (TEWL), hydration and erythema of the face following diamond microdermabrasion. Twenty-eight patients were included in this spilt face study. TEWL, stratum corneum hydration and the degree of erythema were measured from the right and left sides of the face (forehead and cheek) at baseline. One side of the face was treated with diamond microdermabrasion and the other side was left untreated. Measurements were taken right after the procedure and repeated at set time intervals. Diamond microdermabrasion was associated with a statistically significant increase in TEWL immediately after the procedure and at 24 h. However, on day 2, levels of TEWL were back to baseline. An increase in hydration and erythema was observed right after microdermabrasion, but both returned to baseline on day 1. The results show that skin barrier function of the forehead and cheek recovers within 2 days of diamond microdermabrasion. Diamond microdermabrasion performed on a weekly basis, as presently done, is expected to allow sufficient time for the damaged skin to recover its barrier function in most parts of the face.
Microdermabrasion has become a popular method for superficial resurfacing of the epidermis. Despite the popularity of this technique, few studies have examined changes in the levels of lipids (especially ceramide) in the stratum corneum following microdermabrasion.
To assess and analyze changes in the ceramide level in the stratum corneum during the course of serial aluminum oxide microdermabrasion.
Eleven healthy volunteers were enrolled in this study. Each participant underwent microdermabrasion once a week for 5 weeks. Following each procedure, the ceramide level in the resulting epidermal scales was measured.
A statistically significant increase in the ceramide level in the stratum corneum was observed following the first and second microdermabrasion sessions. After the third and fourth sessions, the ceramide level returned to baseline.
The results suggest that microdermabrasion alters the epidermal ceramide level. These findings provide the first evidence of alterations in the lipid barrier following microdermabrasion.
Microdermabrasion (MDA) is a recently introduced noninvasive, nonsurgical, office-based esthetic procedure for revitalizing and rejuvenating the skin. It is a closed-loop vacuum-assisted abrasive procedure, which uses the physical action of inert crystals to exfoliate the skin.
The aim was to evaluate the procedure of MDA in postacne scarring, melasma, and facial rejuvenation, and review the relevant literature.
Ten patients each of postacne scarring, melasma, and facial rejuvenation were treated by a series of weekly MDA sittings alone or in conjunction with a topical retinoid. The results were assessed by patient questionnaire and an objective assessment by two independent observers. The literature was reviewed to find indications and efficacy of MDA.
All the patients of postacne scarring, melasma, and facial rejuvenation reported a mild but definite improvement, which increased when MDA was performed in conjunction with a topical retinoid. Most of the literature based on subjective and patient-dependent assessment parameters points toward a marginal improvement in the skin appearance following repeated procedures.
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.
The prevalence of allergic contact dermatitis in patients who have previously undergone skin peeling has been rarely studied.
We compared the frequency of positive patch test (PT) reactions in a patient group with a history of peeling, to that of a control group with no history of peeling.
The Korean standard series and cosmetic series were performed on a total of 262 patients. 62 patients had previously undergone peeling and 200 patients did not.
The frequency of positive PT reactions on Korean standard series was significantly higher in the peeling group compared with that of the control group (P < 0.05, chi-square test). However, the most commonly identified allergens were mostly cosmetic-unrelated allergens. The frequency of positive PT reactions on cosmetic series in the peeling group was higher than that of the control group, but lacked statistical significance. The frequency (%) of positive PT reactions on cosmetic series in the high-frequency peel group was higher than that of the low-frequency group, but lacked statistical significance.
It appears peeling may not generally affect the development of contact sensitization. Further work is required focusing on the large-scale prospective studies by performing a PT before and after peeling.
Microdermabrasion (MDA) is a safe, simple, and beneficial technique for superficial skin resurfacing. Despite its popular usage, few studies have assessed the efficacy of different MDA protocols applied at the present time. Objectives To assess the effects of MDA generally, as well as to compare the effects of two vs. three passes of MDA in each session for a total number of six therapeutic sessions on skin biophysical characteristics.
In this randomized, investigator-blind, split-face study, 10 patients underwent a series of six MDA treatments with an interval of 2 weeks. One side of the face was treated with two passes of MDA and the other side was treated with three passes, randomly. Stratum corneum hydration, sebum secretion, and skin pH measurements were obtained before and after the procedure on all sessions and also 1 and 4 weeks after the last treatment.
After six sessions of MDA, a decrease in sebum content compared to baseline was shown at the end of treatment sessions, but no statistical difference was observed between two vs. three passes groups (-30.0 [interquartile range, IQR = 50.0] vs. -27.5 [IQR = 125.3], respectively, P = 0.58). Comparison of two treatment groups showed significant higher values of sebum content in the first follow-up after treatment with three passes of MDA. (64.0 [IQR = 52.0] for three passes vs. 45.0 [IQR = 46.0] for two passes, P = 0.04) A significant increase was observed in pH values at the end of treatment series, first and second follow-up after treatment with two passes of MDA.
MDA may have remarkable effects on skin barrier function changes resulting in skin clinical improvements (Cochrane Skin Group identifier: CSG No. 37).
Synopsis
Glycolic acid (GA) and other alpha‐hydroxyacids (AHAs) are common ingredients of products designed to accelerate exfoliation of the skin. It is known that acidic pHs are essential in order to increase the efficacy of AHA‐based products. The formulator is, therefore, obliged to achieve a difficult balance between performance (skin exfoliation) and risks (skin irritation). In order to overcome this problem, many common organic acids, and combinations of them, have been proposed, with marginal improvements. The need for a new chemistry, in order to achieve better results, was evident, particularly from the point of view of safety. We decided, therefore, to investigate the efficacy of perfluoropolyether (PFPE) phosphate, a new acidic material, already proposed for lowering the pH without increasing skin irritation. Two gels containing PFPE phosphate at different pH values (3 and 7), an acidic gel containing GA at pH 3, and a neutral gel, without an active compound, were applied on 20 healthy volunteers and evaluated with regard to effects on the skin:
Exfoliation after a topical pre‐treatment with these gels
Transepidermal water loss (TEWL) and elasticity
The main conclusion of the investigation was that PFPE phosphate has effects, particularly skin exfoliation rate, quite independent of the pH, and comparable to the gel containing GA at pH 3, apparently without the typical drawbacks of AHAs.
The effects of topical glycolic acid and all-trans retinoic acid on stratum corneum barrier function and hydration of human skin were investigated in 6 healthy volunteers utilizing non-invasive techniques. In addition, changes in stratum corneum turnover time induced by the substances were examined using the dansyl chloride fluorescence test. Twelve percent glycolic acid in water and 0.1% retinoic acid in ethanol, respectively, were applied for 60 min once daily, over a period of 2 weeks (5 consecutive days weekly) on dansyl chloride-labelled skin and on untreated skin. During a 10-day application period, both glycolic acid and retinoic acid similarly induced a significant increase in TEWL. However, after discontinuing treatment, TEWL in retinoic acid-exposed skin remained increased. Glycolic acid significantly reduced stratum corneum hydration from day 11 to day 18 (p < 0.05), while retinoic acid induced skin dryness after 9 days of treatment, which persisted until day 18 (p < 0.005). Whereas glycolic acid rapidly induced an intense erythema implying a direct non-specific inflammatory response, the retinoic acid-exposed skin gradually developed erythema. Retinoic acid caused scaling to a greater extent than did glycolic acid, even after treatment cessation. Both glycolic acid and retinoic acid significantly decreased stratum corneum turnover time and stratum corneum turnover time50 (the time in days from labelling until approximately 50% of fluorescence disappeared), compared with the vehicle controls. However, glycolic acid shortened stratum corneum turnover time (12.8 +/- 0.9 days) as well as stratum corneum turnover time50 (7.3 +/- 0.7 d) significantly more than did retinoic acid (15.8 +/- 0.7 d and 9 +/- 0.8 d, respectively). While ethanol (vehicle of retinoic acid) slightly but significantly decreased stratum corneum turnover time (p < 0.05), water (vehicle of glycolic acid) did not. This study showed that both glycolic acid and retinoic acid induced certain functional changes in stratum corneum, mirroring their irritation potential. However, changes at retinoic acid-exposed sites appeared longer-lasting, implying a distinct mode of action. An increase in stratum corneum turnover induced by the substances may be, in part, linked with their irritation properties.
Alpha-hydroxy acids (AHA) such as glycolic acid have recently been used extensively in cosmetic and dermatological formulas. In low concentration (2-5%) glycolic acid is believed to facilitate progressive weakening of cohesion of the intercellular material of the stratum corneum (SC), resulting in uniform exfoliation of its outermost layers (the stratum disjunctum). Since thinning of the SC as well as changes of intercellular lipids could theoretically compromise the barrier functions of the skin, we investigated the mode of AHA action on the SC to determine whether enhanced desquamation compromises the barrier structures of the SC and changes transepidermal water loss (TEWL) values. Electron microscopy of the epidermis biopsied from the volar forearm of human volunteers after 3 weeks of treatment with a 4% glycolic acid formulation twice daily was employed to evaluate 1) epidermal morphology and thickness of the SC, (2) the lamellar body and SC lipid bilayer organization, and (3) desquamative events based on degradation of desmosomes. TEWL values and SC hydration were recorded prior to and at the end of the study. Electron microscopy revealed no ultrastructural changes in the nucleated layers of the epidermis. The lamellar body (LB) secretory system in the stratum granulosum (SG), and intercellular lipid lamellae in the SC in both vehicle- and glycolic acid-treated samples were comparable to normal human SC. Within the SC, enhanced desmosomal breakdown, promoting loss of cohesion and desquamation, was restricted to the stratum disjunctum while desmosomes of the stratum compactum were unaffected. Treated areas displayed histologically, a more compact appearing SC. TEWL values remained unchanged in glycolic acid- and vehicle-treated skin. Our findings indicate that the barrier structures of the SC are not disrupted by glycolic acid formulations at the concentration used. One of the mechanism of action of AHA on the SC seemed to be a "targeted" desmosomal (corneosomal) action without compromising the barrier structures of the skin.
Backgroound: alpha-Hydroxy acids (AHAs) have been reported to improve aging skin. The mechanisms of action of AHAs on epidermal and dermal compartments need clarification. Objective: Our purpose was to determine the effects of AHAs on photoaged human skin by clinical and microanalytic means. Methods: Patients applied a lotion containing 25% glycolic, lactic, or citric acid to one forearm and a placebo lotion to the opposite forearm for an average of 6 months. Thickness of forearm skin was measured throughout the study. Biopsy specimens from both forearms were processed for analysis at the end of the study. Results: Treatment with AHAs caused an approximate 25% increase in skin thickness. The epidermis was thicker and papillary dermal changes included increased thickness, increased acid mucopolysaccharides, improved quality of elastic fibers, and increased density of collagen. No inflammation was evident. Conclusion: Treatment with AHAs produced significant reversal of epidermal and dermal markers of photoaging.
SummaryA method for the determination of skin thickness has been developed using a simple inexpensive high frequency transducer coupled to a commonly used diagnostic scanner. The technique has proved to be quick, easy and reproducible and has the potential to become a readily available investigative tool.
Alpha hydroxyacids (AHAs) are used to enhance stratum corneum desquamation and improve skin appearance. The purpose of this study was to evaluate whether some AHAs improve skin barrier function and prevent skin irritation. Eleven healthy subjects (aged 28 ± 6 years. mean ± SD) entered the study. Six test sites of 8×5 cm (four different AHAs, vehicle only (VE) and untreated control (UNT)) were selected and randomly rotated on the volar arm and forearm. The four different AHAs at 8% concentration in base cream were glycolic acid (GA), lactic acid, tartaric acid (TA) and gluconolactone (GLU). The products were applied twice a day for 4 weeks (2 mg/cm2). At week 4, a 5% sodium lauryl sulphate (SLS) challenge patch test was performed under occlusion for 6 h (HillTop chamber. 18 mm wide) on each site. Barrier function and skin irritation were evaluated by means of evaporimetry (Servomed EP-1) and chromametry (a* value, Minolta CR200) weekly, and at 0.24 and 48 h after SLS patch removal. No significant differences in transepidermal water loss (TEWL) and erythema were observed between the four AHAs at week 4. After SLS challenge. GLU and TA-treated sites resulted in significantly lower TEWL compared with VE, UNT (P<0.01) and GA (P<0.05) both at 24 and 48 h. Similarly, a* values were significantly reduced after irritation in GLU-and TA-treated sites. This study shows that AHAs can modulate stratum corneum barrier function and prevent skin irritation: the effect is not equal for all AHAs. being more marked for the molecules characterized by antioxidant properties.
The dry looking skin seen in many patients with atopic dermatitis reflects a defect in the epidermal barrier, the stratum corneum, as demonstrated by an increased transepidermal water loss (TEWL) and a decreased ability of the stratum corneum to bind water. The absolute amount of water within the stratum corneum is of importance both for barrier properties and for the clinical appearance of the skin. This water content was measured with a new instrument, the Corneometer CM 420, which takes advantage of the high dielectric constant of water. Forty patients with atopic dermatitis were studied--20 with dry skin and 20 with clinically normal skin on non-eczematous areas. The stratum corneum in dry skin was found to have a lower content of water than that in the clinically normal skin (p less than 0.01). Clinically normal skin in patients with atopic dermatitis did not differ significantly from normal control skin. An experiment was performed in vitro in an attempt to correlate the values obtained with the Corneometer to the absolute amount of water within the corneum.
The influence of eccrine sweating on transepidermal water loss (TEWL) was investigated. TEWL was simultaneously measured on both forearms, with and without topical inactivation of the eccrine sweat glands by 0.3 ml of 0.5% aqueous scopolamine hydrobromide (HBr), applied under 1 h occlusive patches. The degree of sweat inhibition, after exercise, was measured at 2, 3 and 4 h after patch removal. In 42 out of 44 subjects, complete sweat inhibition (on exercise) was achieved only at 4 h after removal. After a 15-min rest in a room at 20 degrees C, the pre-exercise TEWL values (at 4 h) on the treated and untreated sites were not different (P greater than 0.05), in 38 out of 44 subjects. By this rest period, sweating due to slight physical, thermal or even emotional stimuli may be prevented in most subjects. In the other 6 subjects, the pre-exercise TEWL values (at 4 h) on the untreated site were 1-1.8 g/m2h higher than (P less than 0.001) on the treated site, due to emotional sweating. Thus, accurate baseline TEWL measurements may only be made after anticholinergic suppression of the sweat glands. In this way, accurate TEWL measurements may be made even outside favourable laboratory conditions, at industrial sites etc., where circumstances are far from ideal. The effect of this agent applied to a skin site previously irritated artificially by a 24-h occlusive sodium lauryl sulphate (SLS, 0.3 ml, 0.5% aq.) patch, was also investigated in 17 subjects. In all subjects, 4 h after removal, sweating (on exercise) was completely inhibited on the scopolamine-treated site, pre-irritated with SLS.(ABSTRACT TRUNCATED AT 250 WORDS)
A 'Minolta Tri-Stimulus Colorimeter II' was evaluated for obtaining objective measurements of early changes in erythema and tanning. The meter showed a subtle, continuous transition between the primary erythematous response and the delayed tanning of skin which was below the visual threshold for detection. Thereafter, the a* (redness) value of the meter showed a significant linear correlation with the dermatologist's perception of erythema while the b* (yellow) value showed a significant correlation with the perception of tanning. This capability of the tri-stimulus colorimeter to simultaneously evaluate the hue and saturation of skin color affords an improved opportunity to quantitate the transition from erythema to tanning without subjective bias.
A method for the determination of skin thickness has been developed using a simple inexpensive high frequency transducer coupled to a commonly used diagnostic scanner. The technique has proved to be quick, easy and reproducible and has the potential to become a readily available investigative tool.
alpha-Hydroxy acids (AHAs) have been reported to improve aging skin. The mechanisms of action of AHAs on epidermal and dermal compartments need clarification.
Our purpose was to determine the effects of AHAs on photoaged human skin by clinical and microanalytic means.
Patients applied a lotion containing 25% glycolic, lactic, or citric acid to one forearm and a placebo lotion to the opposite forearm for an average of 6 months. Thickness of forearm skin was measured throughout the study. Biopsy specimens from both forearms were processed for analysis at the end of the study.
Treatment with AHAs caused an approximate 25% increase in skin thickness. The epidermis was thicker and papillary dermal changes included increased thickness, increased acid mucopolysaccharides, improved quality of elastic fibers, and increased density of collagen. No inflammation was evident.
Treatment with AHAs produced significant reversal of epidermal and dermal markers of photoaging.
Alpha hydroxyacids (AHAs) are used to enhance stratum corneum desquamation and improve skin appearance. The purpose of this study was to evaluate whether some AHAs improve skin barrier function and prevent skin irritation. Eleven healthy subjects (aged 28 +/- 6 years, mean +/- SD) entered the study. Six test sites of 8 x 5 cm (four different AHAs, vehicle only (VE) and untreated control (UNT) were selected and randomly rotated on the volar arm and forearm. The four different AHAs at 8% concentration in base cream were glycolic acid (GA), lactic acid, tartaric acid (TA) and gluconolactone (GLU). The products were applied twice a day for 4 weeks (2 mg/cm2). At week 4, a 5% sodium lauryl sulphate (SLS) challenge patch test was performed under occlusion for 6 h (HillTop chamber, 18 mm wide) on each site. Barrier function and skin irritation were evaluated by means of evaporimetry (Servomed EP-1) and chromametry (a* value, Minolta CR200) weekly, and at 0, 24 and 48 h after SLS patch removal. No significant differences in transepidermal water loss (TEWL) and erythema were observed between the four AHAs at week 4. After SLS challenge, GLU- and TA-treated sites resulted in significantly lower TEWL compared with VE, UNT (P < 0.01) and GA (P < 0.05) both at 24 and 48 h. Similarly, a* values were significantly reduced after irritation in GLU- and TA-treated sites. This study shows that AHAs can modulate stratum corneum barrier function and prevent skin irritation; the effect is not equal for all AHAs, being more marked for the molecules characterized by antioxidant properties.
Aluminum oxide crystal microdermabrasion has recently become popular for facial rejuvenation. Although it is a widely used technique with perceptible benefits, the clinical efficacy on photodamaged skin has yet to be established.
To measure and quantify the effect of microdermabrasion on photodamaged skin.
Ten subjects underwent one treatment a week for five to six treatments. Skin surface roughness, topography, elasticity, stiffness, compliance, temperature, sebum content, and histology were analyzed.
Subjectively, seven patients noticed a mild improvement. Physician analysis of clinical photography indicated mild improvement in the majority of patients. Objectively, immediately following treatment skin temperature increased, sebum content decreased, and a temporary increase in skin roughness and mild flattening of some wrinkles occurred. Dynamic skin analysis demonstrated a perceptible decrease in skin stiffness and an increase in skin compliance. Histology showed slight orthokeratosis and flattening of rete ridges and a perivascular mononuclear cell infiltrate, edema, and vascular ectasia in the upper reticular dermis 1 week after completion of the series of treatments.
Immediately following the procedure, changes occurring in skin characteristics can be measured that are consistent with mild abrasion and increased blood flow. Objective biomechanical analysis demonstrated a statistically significant decrease in skin stiffness and an increase in skin compliance consistent with persistent edema. Subjectively, patients and physicians report a mild improvement in the majority of subjects. Histology showed dramatic vascular changes in the reticular dermis below the level of direct abrasion. The effect of negative pressure may result in these vascular changes.
This report reviews how to set up a laser Doppler perfusion imaging system intended for visualization of skin blood perfusion, capture images and evaluate the results obtained. A brief summary of related papers published in the literature within the areas of skin irritant and allergy patch testing, microdialysis and skin tumour circulation is presented, as well as early applications within other fields such as diabetology, wound healing and microvascular research.
Guidelines for visualization of cutaneous blood flow by laser Doppler perfusion imaging
- A Fullerton
- M Stucker
- Wihelm
- Kp
Fullerton A, Stucker M, Wihelm KP, et al. Guidelines for visualization of cutaneous blood flow by laser Doppler perfusion imaging. Contact Dermatitis 2002;46:129–40.
The effect of alpha hydroxy acids (glycolic and lactic acid) on hairless mouse skin
- Kim Sj
- Park
- Jh
- K Park
Kim SJ, Park JH, Park K, et al. The effect of alpha hydroxy acids (glycolic and lactic acid) on hairless mouse skin. Ann Dermatol 1997;9:253–7.