Skin Pretreatment With Conventional Non-Fractional Ablative Lasers Promote the Transdermal Delivery of Tranexamic Acid

Stem cell-derived exosomes in the treatment of melasma and its percutaneous penetration

BACKGROUND AND OBJECTIVES

Melasma is a refractory skin disease due to its complex pathogenesis and difficult treatment. Studies have found that human umbilical cord mesenchymal stem cell-derived exosomes (hUCMSC-Exos) could serve as a novel cell-free therapeutic strategy in regenerative and esthetic medicine. It could potentially treat melasma, but the skin barrier is a challenge. In this study, we aim to explore the safety and efficacy of hUCMSC-Exos in the treatment of melasma and the means to promote its percutaneous penetration.

MATERIALS AND METHODS

In the animal study about the effect of penetration, percutaneous penetration of PKH67-labeled hUCMSC-Exos was studied under microneedles, 1565 nm nonablative fractional laser (NAFL), and a plasma named Peninsula Blue Aurora Shumin Master (PBASM) treatments, observed by confocal laser scanning microscopy. In the clinical application study, 60 patients with melasma treated in our department were divided into four groups. NAFL combined with normal saline treatment was used for Group A. Microneedles, NAFL, and PBASM combined with hUCMSC-Exos treatments were used for Groups B, C, and D, respectively. Each patient received four treatments at 1-month intervals. Assessments were done using the degree of pain posttreatment, melasma area and severity score, improvement rate, physician global assessment score, satisfaction, and complications.

RESULTS

In the animal study about the effect of penetration, hUCMSC-Exos can penetrate the deep dermis under microneedles, NAFL, and PBASM treatments. In the clinical application study, compared with Group A, Groups B, C, and D showed significantly improved therapeutic effect and patient satisfaction (p < 0.05), and there was no significant difference among Groups B, C, and D.(p > 0.05). Patients in Group B reported higher pain levels than those in the other three groups (p < 0.05); the treatment experience of patients in Group D was better.

CONCLUSION

hUCMSC-Exos can improve the symptoms of melasma safely and effectively. Compared with microneedles, NAFL and PBASM can also achieve a good effect toward promoting penetration. These findings are worthy of exploration and clinical application.

Laser-Assisted Drug Delivery of Tranexamic Acid by Picosecond Laser in Postinflammatory Hyperpigmentation: A Split-Area Double Blind Randomized Prospective Study

Background: Tranexamic acid has been reported to benefit the treatment of postinflammatory hyperpigmentation (PIH). Laser-assisted drug delivery (LADD) could facilitate the efficacy of topically applied drugs into the dermis. This split-area randomized prospective study aims to assess whether early utilization of the LADD procedure with tranexamic acid delivery followed by picosecond lasers can attenuate the PIH better than the utilization of picosecond lasers alone. Patients and methods: Ten post-traumatic cases of PIH in 10 patients (8 female and 2 male) with an average age of 34.2 ± 11.2 years were included in this clinical trial. Using block randomization to determine the treatment side, one side of each area of the PIH was separated from the midline into two halves belonging to the control and tranexamic acid groups. The half area of the tranexamic acid group was further topically applied with 10% tranexamic acid solution. This procedure was repeated every 6 weeks, four times in total. Results: The self-assessment of the hyperpigmentation and overall satisfaction of the treatment outcome were not significantly different between the treatment and control sides. Conclusions: This split-area study revealed that, compared with picosecond alone, there was no significant difference adopting tranexamic acid in LADD after nonablative fractional picosecond laser for PIH.