Inhibition of DNA methylation enhances HLA-G expression in human mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are immunosuppressive multipotent cells under investigation for potential therapeutic applications in regenerative medicine and prevention of graft-versus-host disease. Human leukocyte antigen (HLA)-G contributes to the immunomodulatory properties of MSCs. HLA-G expression in MSCs is very low and diminishes during in vitro expansion. Epigenetic regulation activates HLA-G expression in some cancer cell lines but not in MSCs. In the present study, adipose- and bone marrow-derived MSCs were exposed to the DNA demethylating agent 5-aza-2-deoxycytidine (5-aza-dC) and histone deacetylase inhibitor valproic acid (VPA) and HLA-G mRNA levels assessed using semi-quantitative reverse-transcription PCR. Exposure to 5-aza-dC resulted in HLA-G1 and -G3 upregulation in both early and late passage MSCs. VPA treatment did not induce HLA-G expression in both bone marrow and adipose derived MSCs. Our results provide the first evidence that HLA-G3 could be expressed in MSCs and that methylation-mediated repression is partly responsible for the observed low levels of HLA-G expression in MSCs. Our findings provide insight that treatment of MSCs with specific epigenetic regulatory modulators may improve their immunoregulatory capability for therapeutic applications.

Mutated HLA-G3 localizes to the cell surface but does not inhibit cytotoxicity of natural killer cells.

HLA-G plays an important role in the induction of immune tolerance. Various attempts to produce good manufacturing practice levels of HLA-G as a therapeutic molecule have failed to date partly due to the complicated structure of full-length HLA-G1. Truncated HLA-G3 is simpler and easier to produce than HLA-G1 and contains the expected functional epitope in its only α1 monomorphic domain. In this study, we engineered the ER retrieval and retention signal on HLA-G3's cytoplasmic tail by replacing its RKKSSD motif with RAASSD. We observed that mutated HLA-G3 was highly expressed on the cell surface of transduced K562 cells but did not inhibit cytotoxicity of natural killer cells.

Potent low toxicity inhibition of human melanogenesis by novel indole-containing octapeptides.

BACKGROUND: Abnormal production and accumulation of melanin are characteristics of a number of skin disorders, including postinflammatory hyperpigmentation and melasma. Our objective was to develop and validate novel oligopeptides with potent inhibitory activity against mushroom and human tyrosinase with minimal toxicity toward melanocytes, keratinocytes, and fibroblasts. METHODS: A library of short sequence oligopeptides was docked against the crystal structure of mushroom tyrosinase to screen for favorable binding free energies and direct interaction with the catalytic pocket. The inhibitory activity of the octapeptides and hydroquinone (HQ) was assessed using mushroom and human tyrosinase and melanin content via human primary melanocytes. Effects on cell viability and proliferation were determined using the MTT assay and cytotoxicity via trypan blue exclusion. RESULTS: Octapeptides P16-18 outperformed HQ, the benchmark of hypopigmenting agents, in all tested categories. Prolonged incubation of human keratinocytes, fibroblasts, or melanocytes with 30-3000µM HQ led to 8- to 65-fold greater cell death than with octapeptides. After 6d of incubation with 30µM HQ, we observed 70±3% and 60±2% cell death in melanocytes and fibroblasts, respectively, versus minimal toxicity up to an octapeptide concentration of 3mM. CONCLUSION: Octapeptides P16-18 are potent competitive tyrosinase inhibitors with minimal toxicity toward the major cell types of human skin. GENERAL SIGNIFICANCE: The findings in our study suggest that all three novel octapeptides may serve as safe and efficacious replacements of HQ for the treatment of pigmentary disorders.

Minimally invasive bipolar fractional radiofrequency treatment upregulates anti-senescence pathways.

BACKGROUND: The sirtuin gene family has been implicated in various anti-senescence pathways. Its connection, if any, with the skin wound healing response has yet to be elucidated. OBJECTIVE: The goal of our study was to better understand the effects of FRF treatment on the sirtuin anti-senescence pathway in skin. METHODS: Human abdominal skin was treated with FRF, and then harvested at 0, 2, 14, and 28 days post-treatment to assess for temporal changes in gene expression levels. RESULTS: Decreased levels of SIRT1, 3, 5, and 7 were observed immediately post-FRF treatment. By Day 2, SIRT1, 6, and 7 expressions increased 50-100%. SIRT6 and 7 expression continued to increase through Day 28. Expression levels of apoptosis genes FoxO3 and p53 decreased, while Bax levels increased by Day 28. CONCLUSIONS: Our results raise the possibility that sirtuin activity may be used as an accurate corollary to clinical improvement in skin quality.

Prospective multicenter clinical trial of a minimally invasive temperature-controlled bipolar fractional radiofrequency system for rhytid and laxity treatment.

BACKGROUND: A minimally invasive fractional bipolar radiofrequency (FRF) was developed. OBJECTIVE: To evaluate safety and efficacy of FRF in reducing face and neck rhytides and laxity. MATERIALS AND METHODS: This prospective, open-label, multicenter clinical trial enrolled 100 subjects with mild to severe facial and neck rhytides and laxity at seven centers in a per-protocol analysis. One single-pass FRF treatment was administered through five 32 g-needle electrode pairs at a preselected real-time fixed temperature of 62 to 78°C, energy duration for 3 to 5 seconds, and impedance restrictions of 200 to 3,000 Ohms, ensuring intradermal delivery. Five blinded dermatologists and plastic surgeons graded randomized standardized baseline and follow-up photographs of 53 and 42 subjects at 3- and 6-month follow-up intervals, respectively, using the Fitzpatrick wrinkle and Alexiades-Armenakas laxity scales. Subject assessments and adverse events were recorded in 100 subjects. RESULTS: Blinded evaluations revealed correct pre- and post-treatment identification in 100% of scored cases, mean improvement of 25.6% on the Fitzpatrick Wrinkle Scale and 24.1% on the Alexiades-Armenakas laxity scale at 6 months, and 100% response rate for rhytides and 95% for laxity. Subgroup analysis revealed maximal rhytid reduction in the mean target temperature of 66.7, energy duration of 4.2 seconds, and volume of denatured collagen of mm(3) denatured collagen group. Adverse events included transient erythema, edema, and ecchymoses, resolving within 1 to 5 days, and two incidents of temporary pinpoint depressions. More than 90% of subjects were satisfied or very satisfied. CONCLUSION: Real-time temperature-controlled FRF is a highly reproducible, safe, effective nonsurgical treatment of face and neck rhytides and laxity and provides important insights into neocollagenesis, neoelastogenesis, and clinical outcomes.

Sign and pseudo-sign of Leser-Trélat: case reports and a review of the literature.

BACKGROUND: Leser-Trélat is distinguished by a rare paraneoplastic sign that is characterized by the sudden eruption of multiple seborrheic keratoses (SKs), associated with underlying internal malignancies. Similar non-malignancy-associated SK eruptions are referred to as the "pseudo-sign of Leser-Trélat" (PLT). OBJECTIVE: Two cases of rapid SK eruptions, one the sign of Leser-Trélat (SLT) and one PLT, are presented, and the literature on SLT and PLT is reviewed. METHODS: A literature review of SLT/PLT was performed by searching the PubMed database for all related English published cases. RESULTS: We identified 109 cases of SLT and 12 cases of PLT, with a mean patient age of 61.8 years. SK eruptions were observed before (68.3%), after (22.1%), and at the time of (9.6%) malignancy diagnosis. The malignancy most frequently associated with SLT was gastric adenocarcinoma. The most common anatomical location of SK eruptions was the trunk (18.9%). Frequently reported associated signs and symptoms included pruritus (52%) and acanthosis nigricans (38.7%). The most common treatment included surgery (35.8%), chemotherapy (26.9%), and radiation therapy (26.9%). Treatment resulted in clinical improvement (45%), no change (30%), exacerbation (15%), or initial improvement followed by exacerbation of SKs. Patient outcomes included disease stability/ improvement (48.4%), recurrence (9.7%), exacerbation/metastasis/new malignancy (4.8%), and death (37.1%). LIMITATIONS: This was a retrospective study and excluded non-English published cases. CONCLUSION: This review updates the existing SLT literature and emphasizes the presence of PLT. Clinicians should be aware that SK eruptions may be early manifestations of an internal malignancy or other pathology. To our knowledge, this is the first review examining both SLT and PLT.

Bioactive oligopeptides in dermatology: Part II.

Peptides are central to the regulation and modulation of the chemical reactions and biological responses that occur in nature. Many physiological processes are affected by the interactions of these peptides, including cell proliferation and migration, inflammation, melanogenesis, angiogenesis and innate immunity. Thus, biologically active peptides offer a great potential medically and therapeutically. Moreover, the ability to generate synthetic peptides with attention to specifically modulating their pharmacokinetics and properties for increased potency, delivery and stability has spurred much interest in this rapidly growing field of research. In this review, we focus on the therapeutic uses of bioactive peptides as antimicrobials and effectors of neurotransmitter release. We also highlight the advantages and challenges associated with this new technology and discuss methods for improving oligopeptide transdermal delivery.

Bioactive oligopeptides in dermatology: Part I.

Short sequence amino acids or oligopeptides represent a relatively new and promising area of dermatology. Oligopeptides are defined as peptide sequences ranging from 2 to 20 amino acids. This class of proteins includes potent biologically active compounds, which can modulate various cellular and molecular processes. The medical potential of short sequence peptides was initially characterized many decades ago with the identification of biological mediators such as angiotensin, vasopressin, oxytocin and bradykinin. However, the role of oligopeptides in affecting biological activity within the skin has only recently been explored. Currently, the dermatologic use of protein peptide fragments is a rapidly growing field of research. Recent studies suggest that treatment with various biologically active peptides can result in favourable clinical outcomes such as for the treatment of hyperpigmentation disorders with tyrosinase inhibitors and the use of collagen synthesis modulators to diminish skin laxity. In this review, we explore the roles of biologically active short sequence peptides as potential therapeutics through the modulation of collagen, elastin and melanin synthesis.

Advances in the treatment of melasma: a review of the recent literature.

BACKGROUND: Melasma is an acquired pigmentary disorder classically manifesting as symmetric hyperpigmented macules and patches on the face. It most commonly affects women of reproductive age with darker skin tones but may also affect adolescents, older women, and men. Although its pathogenesis remains unclear, known risk factors include ultraviolet radiation, hormonal variations of pregnancy, thyroid disease, oral contraceptives, and antiseizure medications. Hydroquinone-containing topical agents are the current standard for melasma treatment, but concern about side effects and long-term safety has spurred efforts to develop alternative treatment options. OBJECTIVES: To review recent advances in melasma treatment. MATERIALS AND METHODS: MEDLINE was searched from 2006 to the present for randomized controlled trials (RCTs) of melasma treatments. RESULTS: Nineteen published RCTs were found covering interventions such as topical therapies, chemical peels, and electromagnetic devices. The outcomes of the studies were summarized into tabular form for easy reference and comparison. CONCLUSIONS: Although melasma is difficult to treat, novel therapeutic modalities have emerged. Further RCT need to be performed to better assess the safety and efficacy of these novel treatment modalities, especially for the long-term maintenance of melasma.

Treatment of mild to moderate facial melasma with the Lumixyl topical brightening system.

BACKGROUND: Melasma is a cutaneous disorder associated with an overproduction of melanin by the tyrosinase enzyme. A proprietary oligopeptide (Lumixyl™) was previously shown to competitively inhibit mushroom and human tyrosinase in vitro without the associated cytotoxicity of hydroquinone and to diminish the appearance of facial melasma. OBJECTIVE: The aim of this case study was to determine if the Lumixyl Topical Brightening System (0.01% oligopeptide cream, an antioxidant cleanser, 20% glycolic acid lotion and physical sunscreen) accelerates clearance of mild-to-moderate melasma. RESULTS: All patients showed improvement in their facial melasma with 1 of 4 patients showing complete clearance after just 6 weeks. CONCLUSIONS: Results suggest that this regimen may be a useful new tool to treat mild to moderate melasma.

Microdermabrasion: molecular mechanisms unraveled, part 2.

Microdermabrasion (MDA) remains a common in-office procedure for many dermatologic practices. The procedure offers minimal downtime with a low incidence of side effects, making it a relatively desirable option for skin rejuvenation. Investigators have identified many of the molecular mechanisms behind this technology in an attempt to optimize clinical results. In particular, activation of the wound healing response plays a key role in the remodeling of post-MDA treated skin, although this response varies based on the type of MDA employed. In addition, advances in MDA technology offer new and promising ways to enhance transcutaneous penetration of active ingredients to improve clinical outcomes. Our review addresses innovative applications of MDA in the last 10 years of research.

Microdermabrasion: molecular mechanisms unraveled, part 1.

Microdermabrasion (MDA) remains a common in-office procedure for many dermatologic practices.The procedure offers minimal downtime with a low incidence of side effects, making it a relatively desirable option for skin rejuvenation. Investigators have identified many of the molecular mechanisms behind this technology in an attempt to optimize clinical results. In particular, activation of the wound healing response plays a key role in the remodeling of post-MDA treated skin, although this response varies based on the type of MDA employed.While many studies discuss the clinical applications of MDA and their relation to histologic changes found after treatment, few address the basic science behind the technology.Our review covers progress made in the last 10 years of research, with an emphasis on the molecular mechanisms.

The erbium micropeel: a prospective, randomized trial of the effects of two fluence settings on facial photoaging.

BACKGROUND: Recent studies have suggested that a series of low-energy, single-pass ablative laser resurfacing micropeels can reduce photoaging with decreased downtime. This randomized, prospective single-blinded trial sought to determine the ideal settings of sequential erbium:yttrium-aluminum-garnet (Er:YAG) laser treatments that maximize efficacy and patient satisfaction. METHODS: Forty-six subjects with mild-to-moderate facial dyschromia and rhytides were evenly randomized to two Er:YAG treatment arms. Patients in the lower fluence (LF) (2.5 J/cm2) and higher fluence (HF) (3.8 J/cm2) groups each received three one-pass, full-face treatments one month apart. Patient and investigator assessments of rhytides, dyschromia and global appearance were performed at baseline and at four, eight and 20 weeks using a nominal scale from 1­4. Adverse events and patient satisfaction were also evaluated. RESULTS: Patient scores showed rhytid improvement only with HF treatments. Investigator scores at three months post-treatment showed dyschromia was significantly improved in both study arms, with a 24 and 36 percent reduction for the LF and HF groups, respectively. Global appearance scores improved by 25 and 32 percent, respectively. A trend towards greater post-procedure erythema and time-to-erythema resolution was observed in the HF group. Mild peeling was the most common adverse event. Individuals who underwent LF treatments were more likely to pursue future treatments. CONCLUSION: Both settings resulted in moderate but significant improvement in dyschromia, although only HF treatment improved rhytides. The decreased downtime of LF treatments made this the preferred choice of patients.

Enhanced skin retention and permeation of a novel peptide via structural modification, chemical enhancement, and microneedles.

Hyperpigmentation is a common skin condition with serious psychosocial consequences. Decapeptide-12, a novel peptide, has been found to be safer than hydroquinone in reducing melanin content, with efficacy up to more than 50% upon 16 weeks of twice-daily treatment. However, the peptide suffers from limited transcutaneous penetration due to its hydrophilicity and high molecular weight. Therefore, decapeptide-12 was modified by adding a palmitate chain in an attempt to overcome this limitation. Molecular docking results showed that the two peptides exhibited similar biological activity towards tyrosinase. We also tested the effect of chemical penetration enhancers and microneedles to deliver the two peptides into and through skin, using an in vitro human skin permeation method. It was shown that the palm-peptide achieved the best skin retention owing to the increased lipophilicity. In addition, skin permeation of the palm-peptides was enhanced by the chemical skin penetration enhancers, namely, oleic acid and menthol. Skin permeation of the native peptide was enhanced by the microneedle patch but not the chemical skin penetration enhancers. Cutaneous absorption of the palm-peptides was estimated to have achieved its therapeutic concentration within skin. The combinatory approach of using molecular modification, chemical penetration enhancement, and microneedle patch proves to be useful to enhanceskin permeation of the peptides.

Differential expression of stem cell markers in human follicular bulge and interfollicular epidermal compartments.

Although skin contains a number of stem cell repositories, their characterization has been hindered by a lack of specific markers and an unclear in vivo localization. In this study, we whole mounted single human scalp hair follicles and examined their profiles using in situ immunohistochemistry and multicolor immunofluorescence in search of markers to distinguish between stem cells residing in the interfollicular epidermis (IFE) and bulge. Our study revealed that expression of several biomarkers localized uniquely to the basal IFE (CD34 and CD117), bulge region (CD200), or both (CK15, CD49f, and CD29). In addition, we found that both basal IFE and bulge stem cells did not express CD71 or CD24 suggesting their potential utility as negative selection markers. Dermal papilla but not basal IFE or bulge stem cells expressed CD90, making it a potential positive selection marker for dermal hair follicle stem cells. The markers tested in this study may enable pursuit of cell sorting and purification strategies aimed at determining each stem cell population's unique molecular signature.

Elastometry and clinical results after bipolar radiofrequency treatment of skin.

BACKGROUND: The healing process of a novel radiofrequency bipolar system was recently shown to produce a profound increase in collagen and elastin content. OBJECTIVE: To determine the relationship between subjective clinical improvement scores and changes in objective measures of mechanical skin properties. METHODS AND MATERIALS: Elastometry measurements were made at baseline and 3 months after treatment. All patients received a treatment zone on the lower face. Patient assessments of results and physician ratings of wrinkle and skin laxity were collected at baseline and 3 and 6 months after treatment. Elastometry and clinical results were then compared. RESULTS: Three months after treatment, elastometry measurements showed statistically significant improvement (5-12% decrease in Young's Modulus and 10-16% decrease in retraction time). The average improvement correlated to a 2.6-year improvement in skin property. Physician scores at 3 months showed a statistically significant improvement of 1.42 grades on the Fitzpatrick scale for wrinkles and 0.66 grades on the Alexiades scale for skin laxity, increasing to 1.57 and 0.70 improvement, respectively, at 6 months. Eighty-nine percent and 91% of patients were satisfied or very satisfied with the procedure at 3- and 6-month follow-up, respectively. CONCLUSION: Elastometry data showed an average decrease in Young's Modulus and retraction time, both of which suggest that radiofrequency bipolar treatment resulted in more youthful skin. Better mechanical characteristics were consistent with improvements in wrinkles, laxity, and skin quality and appearance.

A predictive model of minimally invasive bipolar fractional radiofrequency skin treatment.

BACKGROUND: A novel bipolar fractional radiofrequency (FRF) system with temperature feedback was recently developed for facial laxity and rhytid treatment. The study objective was to develop a model based on published in vivo human skin data that could be extrapolated to aid physicians in making future dosimetry choices under clinically relevant conditions. METHODS: A standard electrode pair designed for use with the FRF system was modeled using finite element analysis (FEA). The model incorporated temperature feedback from sensors within the electrodes, selectable target dermal temperatures, and an epidermal cooling plate. The model was validated using data obtained during clinical treatments. Thermal injury as a function of target temperatures and electrical conductivity was simulated and then validated using in vivo histology results. RESULTS: Lesion size predicted by the model matched histology samples. Lesion width and height were 1.65 and 1.24 mm compared to 1.75 and 1.21 mm for the model versus in vivo, respectively. The thermal profile remained confined between the proximal and distal ends of the electrodes. Ninety-six percent of power was deposited in the dermis. Dose-response curves showed a nonlinear volume increase to 1.7 and 4.7 mm(3) at target temperatures of 65 and 75 degrees C, respectively, and a low sensitivity to electrical conductivity variation. CONCLUSION: FEA of the Bipolar FRF system revealed that isotherms were mainly within the dermis. Lesion volume was found to be less sensitive to changes in electrical conductivity than to target temperature and duration. Simulation results matched well the in vivo lesion dimensions. To our knowledge, this is the first model of bipolar FRF treatment capable of accurately predicting the thermal response of human skin in vivo. The findings of this study allow for the development of accurate dose-response curves to aid physicians in parameter selection and achieving efficacy and safety profiles.

Bipolar fractional radiofrequency treatment induces neoelastogenesis and neocollagenesis.

BACKGROUND: We recently introduced Renesis, a novel minimally invasive radiofrequency (RF) device, for the treatment of human skin. The wound healing response post-fractional RF (FRF) treatment was examined in human subjects. STUDY DESIGN: The FRF system delivered RF energy directly within the dermis via 5 micro-needle electrode pairs. Tissue temperature was held at 72 degrees C for 4 seconds using an intelligent feedback system. The wound healing response was evaluated histologically and by RT-PCR up to 10 weeks post-RF treatment. Neoelastogenesis and the role of heat shock proteins (HSPs) were assessed by immunohistochemistry. RESULTS: FRF treatment generated a RF thermal zone (RFTZ) pattern in the reticular dermis that consisted of zones of denatured collagen separated by zones of spared dermis. RFTZs were observed through day 28 post-treatment but were replaced by new dermal tissue by 10 weeks. HSP72 expression rapidly diminished after day 2 while HSP47 expression increased progressively through 10 weeks. Reticular dermal volume, cellularity, hyaluronic acid, and elastin content increased. RT-PCR studies revealed an immediate increase in IL-1beta, TNF-alpha, and MMP-13 while MMP-1, HSP72, HSP47, and TGF-beta levels increased by 2 days. We also observed a marked induction of tropoelastin, fibrillin, as well as procollagens 1 and 3 by 28 days post-treatment. CONCLUSION: Our study revealed a vigorous wound healing response is initiated post-treatment, with progressive increase in inflammatory cell infiltration from day 2 through 10 weeks. An active dermal remodeling process driven by the collagen chaperone HSP47 led to complete replacement of RFTZs with new collagen by 10 weeks post-treatment. Furthermore, using both immunohistochemical and PCR studies, we successfully demonstrated for the first time evidence of profound neoelastogenesis following RF treatment of human skin. The combination of neoelastogenesis and neocollagenesis induced by treatment with the FRF system may provide a reliable treatment option for skin laxity and/or rhytids.

Pilot clinical study of a novel minimally invasive bipolar microneedle radiofrequency device.

BACKGROUND AND OBJECTIVES: Noninvasive bipolar and monopolar radiofrequency (RF) deep dermal heating devices have previously been described. A novel minimally invasive RF device employing a bipolar microneedle electrode system is introduced and its resultant thermal effects on human skin in vivo were characterized for the first time. STUDY DESIGN/MATERIALS AND METHODS: An investigational 35 W RF device was configured to operate in bipolar mode delivering energy directly within the dermis using 5 microneedle electrode pairs with real-time feedback of tissue temperature for treatment control. Superficial cooling was achieved using a Peltier device. A range of pulse durations between 1 and 25 seconds, and lesion temperatures between 60 and 80 degrees C were tested in vivo on 15 human subjects. Thermal effects were assessed histologically using either hematoxylin & eosin (H&E) or nitroblue-tetrazoliumchloride (NBTC) staining. Treatment effects and adverse events were also monitored clinically. RESULTS: The investigational bipolar RF device delivered controlled heating within dermal tissue. Histological staining with H&E revealed the presence of zones of denatured collagen within the reticular dermis. Lesions were generated at preselected temperatures between 60 and 80 degrees C. Fractional lesions separated by zones of sparing as well as contiguous lesion patterns were demonstrated. Histological staining with H&E and NBTC revealed sparing of adnexal structures and adipose tissue. No major adverse events were observed. CONCLUSIONS: A novel fractional RF device utilizing a minimally invasive bipolar microneedle delivery system for the treatment of human tissue was developed. Treatment of 15 human subjects illustrated the controlled creation of dermally located thermal coagulation zones, herein known as radiofrequency thermal zones. We discovered that varying the pulse length allowed for fractional sparing of dermal tissue. To our knowledge, this is the first report to describe use of a direct real-time temperature and impedance feedback system to control energy delivery during deep dermal heating.

A split-face, double-blind, randomized and placebo-controlled pilot evaluation of a novel oligopeptide for the treatment of recalcitrant melasma.

Melasma is a cutaneous disorder associated with an overproduction of melanin by the tyrosinase enzyme. A proprietary oligopeptide (Lumixyl) was previously shown to competitively inhibit mushroom and human tyrosinase without the associated toxicity of hydroquinone. The aim of this split-face, randomized, double-blind and placebo-controlled pilot study was to determine the effect of twice-daily topical application of this oligopeptide (0.01% w/w) on moderate, recalcitrant melasma over a 16-week course. Five female participants with Fitzpatrick phototype IV and moderate recalcitrant melasma enrolled and completed the study. Improvement in melasma and overall facial aesthetics as well as assessment of volunteer satisfaction was measured using 10- and five-point grading scales, respectively. Treatment was well tolerated with no visible signs of irritation or allergy. All five participants demonstrated statistically significant improvement in the appearance of melasma and overall facial aesthetics with high patient satisfaction. Results suggest that the oligopeptide may be useful in the treatment of melasma and warrants further evaluation.