Tranexamic Acid Diminishes Laser-Induced Melanogenesis

Oral Tranexamic Acid for Prevention and Treatment of Postinflammatory Hyperpigmentation

BACKGROUND

Postinflammatory hyperpigmentation (PIH) is a skin disorder characterized by hyperpigmentation resulting from heightened inflammation and/or damage to the basement membrane, melanocytes, and keratinocytes, leading to abnormal and excessive pigment deposition. Oral tranexamic acid (TXA), originally used as an antifibrinolytic for managing excessive bleeding, has garnered attention for its demonstrated safety and efficacy in treating melasma. There is a growing body of evidence regarding the use of TXA in the treatment of PIH.

OBJECTIVE

To review the mechanism of action of oral TXA in treating PIH and examine the use of oral TXA in preventing and/or treating PIH associated with laser-based and light-based treatments in individuals with skin color.

METHODS

Review of relevant articles from 2000 to present found in the Cochrane Library, PubMed, Embase, and Google Scholar, regarding the use of oral TXA in the treatment of PIH.

RESULTS

Studies reviewed investigated the efficacy of oral tranexamic acid (TXA) in treating postinflammatory hyperpigmentation (PIH) and use in preventing PIH when used in conjunction with other treatments. All studies demonstrated significant improvement in PIH without significant adverse effects and side effects.

CONCLUSION

Oral tranexamic acid is emerging as a safe and effective treatment in the prevention and treatment of postinflammatory hyperpigmentation.

Tranexamic Acid for the Treatment of Hyperpigmentation and Telangiectatic Disorders Other Than Melasma: An Update

Tranexamic acid (TXA), a synthetic lysine analog, is a commonly used antifibrinolytic and procoagulant agent. Based on its good hemostatic efficacy, it is mainly used clinically for bleeding in trauma, various types of surgical and dental procedures and prevention of bleeding in patients with hemophilia. In recent years, studies have shown that TXA has the effects of anti-melanogenesis, anti-inflammation, anti-angiogenesis and promotes the recovery of the skin barrier, so it has been tried to be used as a treatment for hyperpigmentation and telangiectatic diseases. Oral, topical, intradermal injections and microneedling are all commonly used modes of administration. TXA for melasma is the most studied and has achieved indications in some countries, whereas it is still an off-label drug for many other dyschromia. We review the clinical use of TXA in hyperpigmentation and telangiectatic disorders other than melasma, such as post-inflammatory hyperpigmentation, Riehl's melanosis, rosacea, and post-acne erythema, to provide more evidence for the use of TXA in these disorders, and to provide safer and more cost-effective alternatives for the treatment of these diseases.

Combined multilevel anti-aging strategies and practical applications of dermocosmetics in aesthetic procedures

Management of the signs of facial aging and other cosmetic skin problems have greatly evolved in the past years. People are also seeking to improve their well-being and global skin appearance, and when they consider using cosmetic procedures, they expect natural and long-lasting aesthetic results. Combined dermocosmetic approaches that address the signs of facial aging at all levels are increasingly being used by dermatologists to meet patient expectations while ensuring their safety. Minimally invasive and reversible procedures that can be performed in only one session are popular approaches for skin restructuring and volumizing as they are flexible, rapid and less burdensome for patients. These interventions can achieve even better outcomes when they are combined with cosmeceuticals as pre- or post-procedural adjuvants to prepare the skin, accelerate recovery and sustain results. The use of topical dermocosmetics is also recommended as part of the daily skin care routine to improve skin quality and help maintain skin barrier function. This review thus outlines the most commonly used combined multilevel anti-aging strategies, which start by addressing the deepest skin layers and then the more superficial signs of skin aging. Examples of multi-active cosmeceuticals and skin delivery enhancing systems are also presented, together with examples of the use of dermocosmetics as supportive care for aesthetic procedures, to provide insights into current applications of dermocosmetic products.

Comparative Studies on the Photoreactivity, Efficacy, and Safety of Depigmenting Agents

Depigmenting products are increasingly used to counteract skin hyperpigmentation and related psychosocial issues. This study aimed to compare different depigmenting agents-4-butylresorcinol; bakuchiol; tranexamic acid; ascorbyl glucoside; α-arbutin; and ascorbic acid-for photoreactivity; tyrosinase inhibition; and safety. Photoreactivity was assessed using the Reactive Oxygen Species assay. In vitro tyrosinase inhibition was compared, and cell viability was assessed in B-16V melanocytes to evaluate safety. Results showed 4-butylresorcinol, ascorbyl glucoside, and α-arbutin are non-photoreactive, while for ascorbic acid and bakuchiol it was not possible to reach conclusive results due to the lack of specificity of the ROS assay. 4-Butylresorcinol, acting as a competitive inhibitor, displayed potent tyrosinase inhibition, followed by ascorbic acid and bakuchiol. Both 4-butylresorcinol and bakuchiol reduced cell viability in a concentration-dependent manner. The insights obtained in this work support the development of depigmenting products by providing useful scientific guidance on the photostability, tyrosinase inhibitory efficacy, and skin safety of depigmenting agents.

Is Tranexamic Acid Use Effective in Preventing Postinflammatory Hyperpigmentation after Laser Treatment? A Systematic Review and Meta-Analysis

Postinflammatory hyperpigmentation (PIH) is one of the most prevalent complications of laser treatment. However, comprehensive evidence is lacking to confirm the effect of tranexamic acid (TXA) for the prevention of postlaser PIH. We classified laser combined with TXA as the experimental group and laser alone as the control group from the selected studies in order to determine the efficacy of the extra use of TXA. We conducted a comprehensive literature review of randomized controlled trials (RCTs) that matched TXA coupled with laser vs. laser alone. The melanin index (MI) scores were employed as the clinically improved outcomes. Seven RCTs and a total of 222 individuals were evaluated in this meta-analysis. The findings revealed no statistically significant difference between the TXA and control groups in terms of decrease in mean MI scores at the end of the research ( $P=0.45$ ). The subgroup analysis showed that at month 1, extra use of TXA after laser treatment resulting in a statistically significant decrease in MI as opposed to laser alone ( $P=0.04$ ). However, at months 2 ( $P=0.73$ ), 3 ( $P=0.85$ ), and 6 ( $P=0.64$ ), the decrease in MI scores was not statistically significant. In addition, there was no statistically significant difference between topical, oral, and intradermal TXA on the reduction of MI scores after treatment ( $P=0.61$ ). Furthermore, nausea and menorrhagia occurred in the oral TXA group. The current meta-analysis found limited temporary efficacy of TXA in preventing postlaser PIH after 1 month.

Review of Laser Treatments for Post-Inflammatory Hyperpigmentation in Skin of Color

Post-inflammatory hyperpigmentation is an extremely common disorder of pigmentation in skin of color. It most frequently and severely affects phototypes that are rich in melanin and often has a chronic and unpredictable course. It presents significant treatment challenges and often requires a multi-factorial approach. We review the literature available for the optimal use of laser-based devices in the treatment of post-inflammatory hyperpigmentation, particularly for Fitzpatrick skin phototypes III-VI. For the treatment of post-inflammatory hyperpigmentation in skin of color, lasers remain second line to topical agents based on the variable response, cost, and risk of complications with laser use. For post-inflammatory hyperpigmentation resistant to topicals, laser devices, particularly neodymium:yttrium-aluminum-garnet and fractional photothermolysis systems, can provide adjunctive treatment in skin of color patients when appropriate parameters are used. Future studies would benefit from an objective and consistent assessment to assist with a systematic analysis.

Tranexamic acid may promote melanocores clustering in keratinocytes through upregulation of Rab5b

Tranexamic acid (TXA) is a promising therapeutic agent in melasma that can act on multiple pathophysiologic mechanisms of melasma. However, it is unclear whether TXA affects melanin in keratinocytes. To explore the effect of TXA on melanocores in keratinocytes. The melanocore-incorporated keratinocytes were constructed by co-incubating normal human epidermal keratinocytes (NHEK) with melanocores. After being treated with TXA, autophagy- and melanin-related protein expressions were detected. Then, transcriptome sequencing was used to compare the genetic changes in melanocore-incorporated keratinocytes before and after TXA treatment and further verified the differentially expressed genes. At the same time, the distribution of melanocores in human keratinocytes was observed by transmission electron microscopy. We found that TXA does not promote melanin degradation in primary keratinocytes by inducing autophagy. Protein transport and intracellular protein transport-related genes were enriched after TXA treatment, and Rab5b was significantly upregulated. Transmission electron microscopy showed that the percentage of melanocores distributed in clusters increased after treatment with TXA, which was reduced after Rab5b silencing. In addition, results suggested that melanocores could colocalize with Rab5b and lysosome-associated membrane protein1 (LAMP1). Our study found that Rab5b may be involved in the melanocore distribution in keratinocytes. TXA may promote the clustering distribution of endocytic melanocores through upregulation of Rab5b, representing a potential mechanism of TXA treatment against melasma.

Mechanism of Action of Topical Tranexamic Acid in the Treatment of Melasma and Sun-Induced Skin Hyperpigmentation

Tranexamic acid (TXA) has anti-plasmin activity and has been shown when administered orally to be effective against melasma, for which it is considered first-line pharmacotherapy. Several studies have shown that topically applied TXA is also effective against melasma and skin hyperpigmentation caused by sunburn and inflammation. The TXA concentration in the epidermis and dermis/vasculature has been estimated from its distribution in the skin after closed application, and topically applied TXA has thus been shown to act on neutrophils and mast cells in the dermis and on the vascular system. It is unlikely that topically applied TXA acts on dermal neutrophils or mast cells or on the vascular system to form thrombi. As discussed in the present review, studies on the effects of topical TXA on the hyperpigmentation process indicate that the resulting skin-lightening mechanism involves the suppression of cytokine/chemical mediator production, which stimulates melanin production via the keratinocyte-derived urokinase-type plasminogen activator and plasminogen derived from dermal vascular in the basal layer of the epidermis, thereby suppressing the production of excessive melanin to prevent hyperpigmentation.

Shining Light on Autophagy in Skin Pigmentation and Pigmentary Disorders

Autophagy is a vital process for cell survival and it preserves homeostasis by recycling or disassembling unnecessary or dysfunctional cellular constituents. Autophagy ameliorates skin integrity, regulating epidermal differentiation and constitutive pigmentation. It induces melanogenesis and contributes to skin color through melanosome turnover. Autophagy activity is involved in skin phenotypic plasticity and cell function maintenance and, if altered, it concurs to the onset and/or progression of hypopigmentary and hyperpigmentary disorders. Overexpression of autophagy exerts a protective role against the intrinsic metabolic stress occurring in vitiligo skin, while its dysfunction has been linked to the tuberous sclerosis complex hypopigmentation. Again, autophagy impairment reduces melanosome degradation by concurring to pigment accumulation characterizing senile lentigo and melasma. Here we provide an updated review that describes recent findings on the crucial role of autophagy in skin pigmentation, thus revealing the complex interplay among melanocyte biology, skin environment and autophagy. Hence, targeting this process may also represent a promising strategy for treating pigmentary disorders.

Tranexamic acid: Beyond antifibrinolysis

Tranexamic acid (TXA) is a popular antifibrinolytic drug widely used in hemorrhagic trauma patients and cardiovascular, orthopedic, and gynecological surgical patients. TXA binds plasminogen and prevents its maturation to the fibrinolytic enzyme plasmin. A number of studies have demonstrated the broad life-saving effects of TXA in trauma, superior to those of other antifibrinolytic agents. Besides preventing fibrinolysis and blood loss, TXA has been reported to suppress posttraumatic inflammation and edema. Although the efficiency of TXA transcends simple inhibition of fibrinolysis, little is known about its mechanisms of action besides the suppression of plasmin maturation. Understanding the broader effects of TXA at the cell, organ, and organism levels are required to elucidate its potential mechanisms of action transcending antifibrinolytic activity. In this article, we provide a brief review of the current clinical use of TXA and then focus on the effects of TXA beyond antifibrinolytics such as its anti-inflammatory activity, protection of the endothelial and epithelial monolayers, stimulation of mitochondrial respiration, and suppression of melanogenesis.

Tricuspid valve endocarditis following over-the-counter intravenous injection of skin-whitening products

Intravenous drug use, central catheters and intracardiac devices are known predispositions to right-sided infective endocarditis (IE). We report a case of tricuspid IE caused by Acinetobacter seifertii and Enterobacter bugandensis as a result of intravenous use of skin-whitening products bought online. Clinical implications and pharmaceutical regulations are briefly discussed.

Microneedling-assisted topical tranexamic acid solution versus 4% hydroquinone for treating melasma: A split-face randomized study

BACKGROUND

Melasma, also known as chloasma or mask of pregnancy, is a common, acquired, hyperpigmentary disorder usually affecting females. Tranexamic acid (TA), a derivative of amino acid lysine, has shown promising results over the past few years when used along with other therapies and when used as a stand-alone therapy.

AIM OF THE WORK

In this study, we aimed to evaluate and compare the effectiveness of topically applied tranexamic acid after microneedling versus topically applied hydroquinone (HQ) 4% alone in patients with melasma.

PATIENTS AND METHODS

Fifty selected patients were divided randomly according to the random number allocation method into two groups (25 patients each) of A (topical 4% hydroquinone, nightly application) and B (microneedling + topical 4% TA, every other week).

RESULTS

After eight weeks of treatment, the mean modified MASI score of the HQ treated side changed from 6.604 ± 4.02 to 3.032 ± 1.19 with a mean decrease percentage of 54.8% ± 19.4%. This reduction in modified MASI score was found to be statistically significant, (p < 0.001). MASI score of group B (TA +microneedling) changed from 6.348 ± 3.84 to 3.712 ± 1.19 with mean decrease percentage of 57.4% ± 23.4% which was also statistically significant, (p < 0.001).

CONCLUSION

We demonstrated safety and efficacy of both used modalities and with minimal side effects. Topical HQ application achieved minimal non-significant higher satisfactory results among raters and subjects.

New oral and topical approaches for the treatment of melasma

Melasma is a common, therapeutically challenging, and universally relapsing disorder of hyperpigmentation that is most often observed in women and individuals with Fitzpatrick Skin Types III through VI. The pathogenesis of melasma is complex and protean. Contributing factors that are often implicated in the etiopathogenesis of this condition include a genetic predisposition, intense ultraviolet radiation exposure, and hormonal influences. Therapeutic interventions for melasma include a multimodality approach incorporating photoprotection agents, topical and oral skin lighteners, and resurfacing procedures. Given our expanding knowledge of the pathogenesis of melasma, new and effective treatments are expanding our therapeutic armamentarium. This article reviews new and emerging oral and topical treatments for melasma.

Evaluation of Therapeutic Efficacy and Safety of Tranexamic Acid Local Infiltration in Combination with Topical 4% Hydroquinone Cream Compared to Topical 4% Hydroquinone Cream Alone in Patients with Melasma: A Split-Face Study

Introduction

Melasma is an acquired pigmentary disorder characterized by hyperpigmented macules and/or patches affecting sun-exposed skin. Tranexamic acid (TA) can reduce melanin content of epidermis. Thus, we conducted this study to evaluate the efficacy and safety of tranexamic acid local infiltration in combination with topical 4% hydroquinone cream compared to topical 4% hydroquinone cream alone in patients with melasma.

Material and Methods

This study was a prospective assessor- and analyst-blind, randomized split-face clinical trial which was performed on patients with bilateral malar epidermal melasma. A total of 55 patients were enrolled, and each side of their face was randomly allocated to either TA+HQ or HQ alone treatment. The MASI score was applied as an objective measurement to compare two treatment groups. The patient's satisfaction of melasma treatment was evaluated using a four-scale grading, as well.

Results

The mean of MASI score in week 16 decreased in both groups significantly (p < 0.01). The therapeutic outcomes were significantly better in TA+HQ group than HQ group (p=0.001). Patients satisfaction with treatment was significantly higher in the TA + HQ group. The difference between the two groups regarding side effect occurrence was not statistically significant.

Conclusion

Addition of tranexamic acid injections to conventional hydroquinone therapy can increase the efficacy of topical treatment. This trial is registered with IRCT2015110324865N1.

Trabectedin is a promising antitumor agent potentially inducing melanocytic differentiation for clear cell sarcoma

Clear cell sarcoma is an aggressive soft tissue sarcoma and highly resistant to conventional chemotherapy and radiation therapy. This devastating disease is defined by EWSR1-ATF1 fusion gene resulting from chromosomal translocation t(12;22)(q13;q12) and characterized by melanocytic differentiation. A marine-derived antineoplastic agent, trabectedin, inhibits the growth of myxoid liposarcoma and Ewing sarcoma by causing adipogenic differentiation and neural differentiation, respectively. In this study, we examined the antitumor effects and mechanism of action of trabectedin on human clear cell sarcoma cell lines. We showed that trabectedin decreased the cell proliferation of five clear cell sarcoma cell lines in a dose-dependent manner in vitro and reduced tumor growth of two mouse xenograft models. Flow cytometry and immunoblot analyses in vitro and immunohistochemical analysis in vivo revealed that trabectedin-induced G2/M cell cycle arrest and apoptosis. Furthermore, trabectedin increased the expression of melanocytic differentiation markers along with downregulation of ERK activity in vitro and the rate of melanin-positive cells in vivo. These results suggest that trabectedin has potent antitumor activity against clear cell sarcoma cells by inducing cell cycle arrest, apoptosis, and, in part, by promoting melanocytic differentiation through inactivation of ERK signaling. Our present study indicates that trabectedin is a promising differentiation-inducing agent for clear cell sarcoma.

Tranexamic acid inhibits melanogenesis by activating the autophagy system in cultured melanoma cells

BACKGROUND

As interest in skin beauty increases, the development of new skin whitening agents has attracted substantial attention; however, the action mechanism of the agents developed so far remains largely unknown. Tranexamic acid (TXA) is commonly being used to reduce melanin synthesis in patients with melasma and also used as a raw material for functional whitening cosmetics, although its action mechanism is poorly understood. Autophagy has been well known to be essential for tissue homeostasis, adaptation to starvation, and removal of dysfunctional organelles or pathogens. Recent studies have shown that autophagy regulators might have prominent roles in the initial formation stage of the melanosome, a lysosome-related organelle synthesizing melanin pigments. However, there is still no direct evidence showing a relationship between the activation of the autophagy system and the melanogenesis.

OBJECTIVE

To investigate whether TXA can inhibit melanogenesis through the activation of autophagy in a melanoma cell line.

METHODS

B16-F1 melanoma cells were treated with TXA and the levels of autophagy- and melanogenesis-related proteins were determined by Western blottings. The direct effect of TXA-mediated autophagy activation on melanin production was further evaluated by transfecting the cells with 60 pmols of small interfering RNAs (siRNAs)-targeting the mechanistic target of rapamycin (mTOR) and the autophagy-related protein 5 (Atg5).

RESULTS

The results of Western blottings showed that TXA enhanced the production of autophagy-related proteins such as mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase (ERK)1/2, Beclin-1, Atg12, and light chain 3 (LC3) I-II, whereas it decreased the synthesis of the mTOR complex. Confocal microscopy clearly showed that TXA treatment resulted in the formation of autophagosomes in B16-F1 cells, as revealed by immunostaining with an anti-LC3 antibody. The production of melanogenesis-associated proteins, including microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase-related protein 1 and 2 (TRP1/2), were clearly downregulated by the treatments with TXA. These results suggest that TXA can mediate a decrease in melanin synthesis by alleviating the production of tyrosinase and TRP1/2, along with lowered MITF protein levels. Furthermore, after treatment with TXA, siRNAs- targeting to mTOR and Atg5 increased melanin synthesis by 20% and 40%, respectively, compared to that in non-transfected cells, in a dose-dependent manner. These results further confirmed that TXA can inhibit melanogenesis by activating the autophagy system.

CONCLUSION

Collectively, the results demonstrate that TXA can reduce melanin synthesis in melanoma B16-F1 cells by activating the ERK signaling pathway and the autophagy system.

Tranexamic Acid in the Treatment of Melasma: A Review of the Literature

Melasma is a common acquired pigmentary disorder marked by irregular hyperpigmented macules or patches and most commonly occurs in women of darker skin color. It is a chronic often-relapsing condition that causes negative psychosocial effects in those affected. Current treatments such as hydroquinone, kojic acid, and retinoids, among others, demonstrate variable efficacy and side-effect profiles. We conducted a comprehensive literature review examining the use of tranexamic acid (TA), a well-known anti-fibrinolytic agent, in the treatment of melasma. TA delivered orally, topically, and through physical methods works via the inhibition of ultraviolet (UV)-induced plasmin activity in keratinocytes. Predefined search terms were entered into PubMed. Articles were then independently screened by two authors to include only those written in the English language and relating to human subjects with at least mild melasma. The search identified 28 articles, 15 of which met the criteria for full review. The review revealed that TA treatment for melasma is equally effective or more effective than other standard therapies and may induce fewer side effects. Our comprehensive review suggests that TA may be a promising treatment option for melasma because of its demonstrated effectiveness alone and in combination with other modalities as well as its limited side-effect profile.

Efficacy of functional microarray of microneedles combined with topical tranexamic acid for melasma: A randomized, self-controlled, split-face study

To evaluate the efficacy of a functional microarray of microneedles (MNs) plus topical tranexamic acid (TA) for melasma in middle-aged women in China.Thirty female subjects with melasma were enrolled in this study. The left or right side of the face was chosen randomly to be pretreated with a functional microarray of MNs, followed by topical 0.5% TA solution once per week for 12 weeks. The other half-face was the control, treated with a sham device plus topical 0.5% TA solution. At baseline and at weeks 4, 8, and 12 of treatment, clinical (photographic) evaluations and parameters determined by Visia were recorded. At baseline and week 12, patient satisfaction scores and the biophysical parameters measured by Mexameter were also recorded. Side effects were evaluated at baseline and at the end of the 12 weeks.In total, 28 women (93.3%) completed the study. The brown spots' scores measured by Visia were significantly lower on the combined therapy side than on the control side at 12 weeks after starting treatment; there was no significant difference between sides at 4 or 8 weeks. After 12 weeks, melanin index (MI) decreased significantly in both 2 groups, and the MI was significantly less on the combined side at week 12. Transepidermal water loss, roughness, skin hydration, skin elasticity, and erythema index showed no significant differences between 2 sides at baseline, 4, 8, and 12 weeks after treatment. Physicians' evaluations of photographs showed better results at week 12 with combined therapy: >25% improvement was observed in the MNs plus TA side in 25 patients, and in the TA side in only 10 patients. Subjective satisfaction scores on both sides increased significantly. The participants were more satisfied with the results of the combined therapy side than the control side. No obvious adverse reactions were observed throughout the study.Combined therapy with a functional microarray of MNs and topical TA solution is a promising treatment for melasma.

Lactoferrin inhibits melanogenesis by down-regulating MITF in melanoma cells and normal melanocytes

The aim of this study was to evaluate the effect of bovine lactoferrin (bLf) on melanin-producing cells and to elucidate its mechanism of action. We tested the anti-melanogenic effect of bLf on a 3-dimensional cultured pigmentation skin model and confirmed a 20% reduction in pigmentation, suggesting that bLf was transdermally absorbed and it suppressed melanin production. Treatment of human melanoma cells with bLf resulted in a significant, dose-dependent suppression of melanin production. Apo-bLf and holo-bLf suppressed melanogenesis to the same degree as bLf. The key feature behind this anti-melanogenic effect of bLf was the down-regulation of the microphthalmia-associated transcription factor (MITF), leading to the suppression of tyrosinase activity. Treatment with bLf resulted in both decreased expression of MITF mRNA and enhanced degradation of MITF protein. However, the primary effector was enhanced phosphorylation of extracellular signal-regulated kinase (ERK), leading to the phosphorylation and degradation of MITF. Our finding that bLf suppresses melanin production in melanocytes indicates that bLf is a possible candidate for application as a skin-whitening agent.

Tranexamic Acid and Supportive Measures to Treat Wasting Marmoset Syndrome

Wasting marmoset syndrome (WMS) has high incidence and mortality rates and is one of the most important problems in captive common marmoset (Callithrix jacchus) colonies. Despite several reports on WMS, little information is available regarding its reliable treatment. We previously reported that marmosets with WMS had high serum levels of matrix metalloproteinase 9 (MMP9). MMP9 is thought to be a key enzyme in the pathogenesis of inflammatory bowel disease, the main disease state of WMS, and is activated by plasmin, a fibrinolytic factor. In a previous study, treating mice with an antibody to inhibit plasmin prevented the progression of inflammatory bowel disease. Here we examined the efficacy of tranexamic acid, a commonly used plasmin inhibitor, for the treatment of WMS, with supportive measures including amino acid and iron formulations. Six colony marmosets with WMS received tranexamic acid therapy with supportive measures for 8 wk. The body weight, Hct, and serum albumin levels of these 6 marmosets were increased and serum MMP9 levels decreased after this regimen. Therefore, tranexamic acid therapy may be a new and useful treatment for WMS.

Skin permeation and retention of topical bead formulation containing tranexamic acid

The objective of this study is to develop a topical bead formulation of tranexamic acid (TA) which can be used concomitantly with laser treatment. The bead formulation of TA (TAB) was successfully prepared by fluidized bed drying method. Physicochemical properties of the TAB were evaluated in terms of chemical stability of TA and differential scanning calorimetry. TA in the bead was stable up to six months at 25°C and existed as amorphous state. In vitro skin permeation and in vivo skin retention of TA in the beads were significantly higher compared to a commercial product. When the bead was dissolved into distilled water and applied concomitantly with laser treatment, the amount of TA retained in the skin in the in vivo study was inversely proportional to the energy levels of laser treatment, indicating absorption into subcutaneous tissue and drainage to systemic circulation. Therefore, when laser treatment is used concomitantly with TAB, energy level should be very carefully monitored to avoid possible adverse events associated with systemic side effects of TA.

Postinflammatory hyperpigmentation associated with treatment of solar lentigines using a Q-Switched 532-nm Nd: YAG laser: a multicenter survey

PURPOSE

To characterize the risk factors of Korean patients for postinflammatory hyperpigmentation (PIH) during treatment of solar lentigines using a Q-switched 532-nm Nd: YAG (QS 532 NY) laser.

MATERIALS AND METHODS

The present retrospective multicenter study was conducted at the dermatology clinics of five tertiary hospitals in Korea. Between October 2007 and January 2013, 516 patients were enrolled and reviewed for clinical features and factors associated with PIH.

RESULTS

The overall incidence of PIH was 20.3%. We demonstrated that patients with erythematous lentigines presented with PIH more frequently compared with those without erythematous lentigines. Among several coexisting conditions, facial diffuse dyschromia was significantly associated with PIH. Furthermore, PIH occurred more frequently in patients with invisible pores and velvety skin. However, age, sex, Fitzpatrick skin's phototype and season of treatment showed little association with PIH.

CONCLUSIONS

When a QS 532 NY laser is used to treat individuals with erythematous lentigines, invisible pores and velvety skin, and facial diffuse dyschromia, clinicians should be cautious and consider preventive measures.