Usefulness of Skin Explants for Histologic Analysis after Fractional Photothermolysis

Mitochondrial activity is the key to the protective effect of β-Lapachone, a NAD+ booster, in healthy cells against cisplatin cytotoxicity

BACKGROUND

Cisplatin (CDDP) is a first-line chemotherapeutic drug for treating various cancers. However, CDDP also damages normal cells and causes many side effects. Recently, CDDP has been demonstrated to kill cancer cells by targeting mitochondria. Protecting mitochondria might be a potential therapeutic strategy for CDDP-induced side effects. β-Lapachone (β-lap), a recognized NAD⁺ booster, has been reported to regulate mitochondrial activity. However, it remains unclear whether maintaining mitochondrial activity is the key factor in the protective effects of β-lap in CDDP-treated normal cells.

PURPOSE

In this study, the protective effects of β-lap on mitochondria against CDDP cytotoxicity in normal cells were evaluated.

STUDY DESIGN

In vitro cell models were used in this study, including 3T3 fibroblasts, human dermal fibroblasts, MCF-7 breast cancer cells, and MDA-MB-231 breast cancer cells.

METHODS

Cells were treated with CDDP and β-lap, and cell survival, NAD⁺, mitochondrial activity, autophagy, and ATP production were measured. Various inhibitors and siRNAs were used to confirm the key signal underlying the protective effects of β-lap.

RESULTS

The results demonstrated that β-lap significantly decreased CDDP cytotoxicity in normal fibroblasts. With various inhibitors and siRNAs, β-lap reduced CDDP-induced damage to normal fibroblasts by maintaining mitochondrial activity and increasing autophagy through the NQO1/NAD⁺/SIRT1 axis. Most importantly, the protective effects of β-lap in fibroblasts did not affect the therapeutic effects of CDDP in cancer cells. This study indicated that mitochondrial activity, energy production, and NQO1 levels might be crucial responses separating normal cells from cancer cells under exposure to CDDP and β-lap.

CONCLUSION

β-lap could be a good synergistic drug for reducing the side effects of CDDP without affecting the anticancer drug effect.

Comparison of 1565-nm Nonablative Fractional Laser and 10600-nm Ablative Fractional Laser in the Treatment of Mild to Moderate Atrophic Acne Scars

BACKGROUND

The 10,600-nm ablative fractional laser (AFL) is widely used for treating facial atrophic acne scars but with evident side effects. By contrast, the common Er:Glass non-AFL (NAFL) is safer but lacks of comparable outcomes. A novel 1,565 nm Er:Glass NAFL improves thermal energy delivery and could yield better outcomes.

OBJECTIVE

We aimed to compare the effectiveness and safety between the 1,565-nm NAFL and 10,600-nm AFL in treating mild-to-moderate facial atrophic acne scars.

METHODS

Nineteen patients with mild-to-moderate bilateral facial atrophic acne scars were enrolled in a randomized split-face trial, which involved 3-session procedures for each laser. The effectiveness and safety were evaluated by doctors and patients who were blinded to the treatment assignment.

RESULTS

Both lasers improved the acne scar profiles comparably. A marked reduction in erythema, crusting durations, and degree of pain were noted on the sides treated with the 1,565-nm NAFL, relative to those treated with the 10,600-nm AFL.

CONCLUSION

Both 1,565 nm-NAFL and 10,600-nm AFL can improve mild-to-moderate acne scars. Patients should never expect complete resolution. The 1,565-nm NAFL has less side effects.

Treatment of atrophic acne scars: Topical or intralesional plasma gel?

BACKGROUND

Atrophic post-acne scarring is considered to be a therapeutic challenge.

OBJECTIVES

The aim was to compare the safety and efficacy of (A) FCL combined with intradermal injection of plasma gel, (B) FCL combined with topical application of plasma gel, and (C) FCL monotherapy in the treatment of atrophic post-acne scars.

METHODS

Thirty patients with facial atrophic post-acne scars were enrolled in this study and randomly assigned into one of three groups. All of them underwent four treatment sessions at 4-weeks intervals. They were assessed objectively by the quantitative global scarring grading system (GSGS). This system was applied at baseline, and after 1- and 6-month follow-up (FU). Subjective assessments were performed through the global esthetic improvement scale (GAIS) and level of patient satisfaction. The DLQI questionnaire was employed at the baseline and 6-month FU.

RESULTS

According to the quantitative GSGS scores, the reductions in group A (68.4%) and group B (63%) scores were comparable, and both were significantly higher than that in group C (41.2%) in all steps of evaluation. At 6-month FU, both groups A and B showed further significant improvement, while group C did not. Based on the GAIS and patients' satisfaction, there were no significant differences between all groups. The reductions in DLQI scores in groups A and B were comparable; however, both were significantly higher than group C (P < .001).

CONCLUSIONS

The combination of plasma gel and FCL resurfacing was noticeably outstanding in their efficacy and impact on the patients' quality of life.

Tracing skin aging process: a mini- review of in vitro approaches

Skin is a rather complex, yet useful organ of our body. Besides, skin aging is a complicated process that gains a growing interest as mediates many molecular processes in our body. Thus, an efficient skin model is important to understand skin aging function as well as to develop an effective innovative product for skin aging treatment. In this mini review, we present in vitro methods for assessments of skin aging in an attempt to pinpoint basic molecular mechanisms behind this process achieving both a better understanding of aging function and an effective  evaluation of potential products or ingredients that counteract aging. Specifically, this study presents in vitro assays such as 2D or 3D skin models, to evaluate skin aging-related processes such as skin moisturization, photoaging, wound healing, menopause, and skin microbiome as novel efforts in the designing of efficacy assessments in the development of skincare products.

Human skin explant model for the investigation of topical therapeutics

The development of in vitro and ex vivo models to mimic human illness is important not only for scientific understanding and investigating therapeutic approaches but also to mitigate animal testing and bridge the inter-species translational gap. While in vitro models can facilitate high-throughput and cost-efficient evaluation of novel therapeutics, more complex ex vivo systems can better predict both desirable and adverse in vivo effects. Here we describe an ex vivo cultured human skin explant model in which we have characterized pathological tissue integrity, barrier function and metabolic stability over time. Our findings suggest that human skin can be successfully cultured for pharmacodynamic use up to and beyond 9 days without any adverse physiological consequence.

Improvements in Skin Quality Biological Markers in Skin Explants Using Hyaluronic Acid Filler VYC-12L

Hyaluronic acid (HA), both crosslinked and uncrosslinked, is used clinically to treat fine lines and provides additional improvements in skin quality attributes. The purpose of this study was to assess potential early differences in the expression of biological markers of skin quality in living human skin explants injected with uncrosslinked and crosslinked HA gels.

Methods

Living human skin explants injected with VYC-12L or noncrosslinked HA with mannitol (HYD) and noninjected controls were assessed via microscopy, histology, and immunohistochemistry on days 3 and/or 8 for biological markers of elasticity (collagen density, elastin, fibrillin-1) and hydration [aquaporin-3, acidic glycosaminoglycans (GAGs), HA]. Hydration was also assessed via a corneometer probe on days 0, 1, 2, and 8.

Results

On day 3 versus controls, VYC-12L moderately increased collagen density in the upper reticular dermis and clearly increased fibrillin-1 expression, with slight increases persisting on day 8. Increases with HYD were smaller and did not persist on day 8. Both VYC-12L and HYD increased aquaporin-3 expression and GAG content on days 3 and 8, but VYC-12L produced greater GAG increases in the reticular dermis. Day 8 instrument-assessed hydration increased by 49% and 22% for VYC-12L and HYD, respectively. Elastin expression in oxytalan and elaunin fibers was unchanged. Upper-dermal HA reductions suggested HA injection-induced hyaluronidase expression.

Conclusion

VYC-12L produced greater, more lasting improvements in biological markers of skin quality than HYD.

Ex vivo culture of keratinocytes on papillary and reticular dermal layers remodels skin explants differently: towards improved wound care

In this study, we characterised the effect that seeding keratinocytes on the papillary and reticular dermis had on the extracellular matrix and tissue integrity ex vivo. Human skin explants from consented patients (n = 6) undergoing routine surgery were cultured at a liquid-air interface, dermal-side up, and autologous keratinocytes seeded on the exposed papillary or reticular layer. After 7-21 days, histological and immunohistochemical evaluation of the morphology and extracellular matrix was performed. While the dermis remained robust in all explants cultures, keratinocytes seeded on the papillary layer showed less tissue infiltration and remodelling and formed clusters across the tissue. In contrast, keratinocytes seeded on the reticular layer infiltrated the tissue homogenously with an intact single-cell-layer surface coverage and structural changes characterised by increased deposition of ground substance, glycosaminoglycans, and collagen VII in 14 days. In addition, while the papillary section showed more new laminin deposition by 14 days than the reticular section, the latter expressed more connexin 43. These differences in re-epithelialisation and extracellular matrix characteristics suggest that wound depth and graft thickness may play a key role in wound healing and indicate that ECM characteristics should be factored in when designing biomaterials for wound applications and in the selection of recipient sites when using cells for grafting.