The role of FtsH complexes in the response to abiotic stress in cyanobacteria

FtsH proteases (FtsHs) belong to intramembrane ATP-dependent metalloproteases which are widely distributed in eubacteria, mitochondria, and chloroplasts. The best studied role of FtsH in Escherichia coli includes quality control of membrane proteins, regulation of response to heat shock, superoxide stress and viral infection, and control of lipopolysaccharide biosynthesis. While heterotrophic bacteria mostly contain a single indispensable FtsH complex, the photosynthetic cyanobacteria usually contain three FtsH complexes: two heterocomplexes and one homocomplex. The essential cytoplasmic FtsH1/3 most probably fulfils a role similar to other bacterial FtsHs whereas the thylakoid FtsH2/3 heterocomplex and FtsH4 homocomplex appear to maintain the photosynthetic apparatus of cyanobacteria and optimize its functionality. Moreover, recent studies suggested involvement of all FtsH proteases in a complex response to nutrient stresses. In this review, we aim to comprehensively review the functions of the cyanobacterial FtsH complexes specifically under stress conditions with emphasis on nutrient deficiency and high irradiance. We also point to various unresolved issues concerning the FtsH functions, which deserve further attention.

A novel professional-use synergistic peel technology to reduce visible hyperpigmentation on face: Clinical evidence and mechanistic understanding by computational biology and optical biopsy

Topicals and chemical peels are the standard of care for management of facial hyperpigmentation. However, traditional therapies have come under recent scrutiny, such as topical hydroquinone (HQ) has some regulatory restrictions, and high concentration trichloroacetic acid (TCA) peel pose a risk in patients with skin of colour. The objective of our research was to identify, investigate and elucidate the mechanism of action of a novel TCA- and HQ-free professional-use chemical peel to manage common types of facial hyperpigmentation. Using computational modelling and in vitro assays on tyrosinase, we identified proprietary multi-acid synergistic technology (MAST). After a single application on human skin explants, MAST peel was found to be more effective than a commercial HQ peel in inhibiting melanin (histochemical imaging and gene expression). All participants completed the case study (N = 9) without any adverse events. After administration of the MAST peel by a dermatologist, the scoring and VISIA photography reported improvements in hyperpigmentation, texture and erythema, which could be linked to underlying pathophysiological changes in skin after peeling, visualized by non-invasive optical biopsy of face. Using reflectance confocal microscopy (VivaScope®) and multiphoton tomography (MPTflex™), we observed reduction in melanin, increase in metabolic activity of keratinocytes, and no signs of inflammatory cells after peeling. Subsequent swabbing of the cheek skin found no microbiota dysbiosis resulting from the chemical peel. The strong efficacy with minimum downtime and no adverse events could be linked to the synergistic action of the ingredients in the novel HQ- and TCA-free professional peel technology.

Polyphenolic Platform Ameliorated Sanshool for Skin Photoprotection

Natural evolution has nurtured a series of active molecules that play vital roles in physiological systems, but their further applications have been severely limited by rapid deactivation, short cycle time, and potential toxicity after isolation. For instance, the instability of structures and properties has greatly descended when sanshool is derived from Zanthoxylum xanthoxylum. Herein, natural polyphenols are employed to boost the key properties of sanshool by fabricating a series of nanoparticles (NPs). The intracellular evaluation and in vivo animal model are conducted to demonstrate the decreased photodamage score and skin-fold thickness of prepared NPs, which can be attributed to the better biocompatibility, improved free radical scavenging, down-regulated apoptosis ratios, and reduced DNA double-strand breaks compared to naked sanshool. This work proposes a novel strategy to boost the key properties of naturally occurring active molecules with the assistance of natural polyphenol-based platforms.

Compact simultaneous label-free autofluorescence multi-harmonic microscopy for user-friendly photodamage-monitored imaging

Significance

Label-free nonlinear optical microscopy has become a powerful tool for biomedical research. However, the possible photodamage risk hinders further clinical applications.

Aim

To reduce these adverse effects, we constructed a new platform of simultaneous label-free autofluorescence multi-harmonic (SLAM) microscopy, featuring four-channel multimodal imaging, inline photodamage monitoring, and pulse repetition-rate tuning.

Approach

Using a large-core birefringent photonic crystal fiber for spectral broadening and a prism compressor for pulse pre-chirping, this system allows users to independently adjust pulse width, repetition rate, and energy, which is useful for optimizing imaging conditions towards no/minimal photodamage.

Results

It demonstrates label-free multichannel imaging at one excitation pulse per image pixel and thus paves the way for improving the imaging speed by a faster optical scanner with a low risk of nonlinear photodamage. Moreover, the system grants users the flexibility to autonomously fine-tune repetition rate, pulse width, and average power, free from interference, ensuring the discovery of optimal imaging conditions with high SNR and minimal phototoxicity across various applications.

Conclusions

The combination of a stable laser source, independently tunable ultrashort pulse, photodamage monitoring features, and a compact design makes this new system a robust, powerful, and user-friendly imaging platform.

A Multi-center Trial Evaluating a Serum Comprised of Plant-based Adaptogens Targeting Skin Quality

Objective

The ability of the skin to maintain homeostasis declines with age. Adaptogens support the capacity of the skin to respond to stress. We sought to evaluate the efficacy of a novel serum comprised of plant-based adaptogens for improving photoaged skin following twice-daily application.

Methods

A multi-center, 12-week trial was conducted in participants aged 45 to 65 years, Fitzpatrick Skin Type (FST) I to VI, with mild-to-severe photoaging based on a 10-point grading scale (3 [Minimum] to 7 [Maximum]). Visible improvements were assessed in erythema, pore size, skin dullness, skin texture, and uneven pigmentation utilizing a six-point grading scale (0=None to 5=Severe). Global skin quality was measured utilizing our Global Skin Quality Index (GSQI). Sebum measurements were obtained in a subset of participants. Patient satisfaction and tolerability were recorded throughout the study.

Results

Fifty-three participants were enrolled and completed the study. Mean age was 56 years and 66 percent were White, 17 percent were Black, 8 percent were Hispanic, 6 percent were Asian/Pacific Islander, and 81 percent had moderate photodamage. At Week 12, significant mean percent improvements from baseline were demonstrated in erythema (50%), dullness (44%), texture (52%), pore size (23%), and uneven pigmentation (21%; all p<.0001). Significant GSQI improvements from baseline were observed at Week 12 (39%; p<0.0001). Significant mean reductions from baseline in skin surface sebum were demonstrated at Week 12 (-38%; p<0.0001). All adverse events (AEs) were mild and transient.

Conclusion

A novel serum comprised of plant-based adaptogens, demonstrated improvements from baseline in the appearance of erythema, dullness, texture, pore size, uneven pigmentation, and global skin quality over 12 weeks. Participants reported high levels of satisfaction, with mild, transient AEs reported.

Deep learning-based photodamage reduction on harmonic generation microscope at low-level optical power

The trade-off between high-quality images and cellular health in optical bioimaging is a crucial problem. We demonstrated a deep-learning-based power-enhancement (PE) model in a harmonic generation microscope (HGM), including second harmonic generation (SHG) and third harmonic generation (THG). Our model can predict high-power HGM images from low-power images, greatly reducing the risk of phototoxicity and photodamage. Furthermore, the PE model trained only on normal skin data can also be used to predict abnormal skin data, enabling the dermatopathologist to successfully identify and label cancer cells. The PE model shows potential for in-vivo and ex-vivo HGM imaging.

Damaging effects of UVA, blue light, and infrared radiation: in vitro assessment on a reconstructed full-thickness human skin

Introduction

Exposure to solar radiation can cause a range of skin damage, including sunburn, erythema, skin carcinogenesis, the release of reactive oxygen species (ROS), inflammation, DNA damage, and photoaging. Other wavelengths beyond UVB, such as UVA, blue light, and infrared radiation, can also contribute to the harmful effects of solar radiation. Reconstructed full-thickness human skin has the potential to serve as effective predictive in vitro tools for evaluating the effects of solar radiation on the skin. The aim of this work was to evaluate the damaging effects of UVA, blue light, and infrared radiation in a full-thickness skin model in terms of viability, inflammation, photoaging, tissue damage, photocarcinogenesis.

Methods

Full thickness skin models were purchased from Henkel (Phenion FT; Düsseldorf, Germany), and irradiated with increasing doses of UVA, blue light, or infrared radiation. Different endpoints were analyzed on the tissues: Hematoxylin-eosin staining, inflammation mediators, photoaging-related dermal markers and oxidative stress marker GPX1, evaluated by real-time quantitative PCR, as well as photocarcinogenesis markers by Western Blot.

Results and Discussion

The results showed differential responses in cytokine release for each light source. In terms of photoaging biomarkers, collagen, metalloproteinases 1 and 9, elastin, and decorin were modulated by UVA and blue light exposure, while not all these markers were affected by infrared radiation. Furthermore, exposure to UVA and blue light induced loss of fibroblasts and modulation of the photocarcinogenesis markers p53 and p21. In conclusion, the presented results suggest that the various wavelengths of solar light have distinct and differential damaging effects on the skin. Understanding the differential effects of UVA, blue light, and infrared radiation can serve as a valuable tool to investigate the efficacy of photoprotective agents in full thickness skin models.

Kangfuxin liquid reduces the ultraviolet B-induced photodamage of HaCaT cells by regulating autophagy

Kangfuxin liquid (KFX), an extract of the American cockroach, has been clinically proven to be effective in various skin damage disorders, but there are no reports on its use in photodamage. We explored the effect of KFX on ultraviolet B (UVB)-induced photodamage and whether its mechanism was related to autophagy. We found that KFX treatment reduced UVB-induced reactive oxygen species production and improved the vitality of cells inhibited by UVB irradiation. The expression of LC3 (A/B), which was inhibited after UVB irradiation, could be rescued by KFX treatment. Furthermore, KFX may upregulate the level of cellular autophagy by regulating the AMPK-mTOR signaling pathway. When the autophagy inhibitor wortmannin was used to inhibit autophagy, the protective effect of KFX on cells was diminished or even disappeared. Our study suggests that KFX may resist UVB-mediated oxidative stress damage of HaCaT through the induction of autophagy.

Antioxidant Skincare Treatment for Hyperpigmented and Photodamaged Skin: Multi-Center, Open-Label, Cross-Seasonal Case Study

Objective

The objective of this study is three-fold. Firstly, to evaluate an enhanced vitamin C serum (eVCS) and its' combination with a retinol-bakuchiol serum (RBS) on pigmentation in vitro. Secondly, to evaluate the effect of the eVCS on skin function ex vivo. Lastly, to evaluate eVCS and RSB in the treatment of facial hyperpigmentation and overall photodamage across a range of opposing environments.

Methods

MelanoDerm™ tissues were topically treated with the eVCS, and a eVCS and RSB blend for 14 days, and then a melanin assay was performed. Surgical waste facial skin explants were incubated with the eVCS or control for five days and then fixed and stained for skin physiology and structure. A 12-week, IRB approved, study on female subjects (n=29, aged 35 to 65) with moderate global facial hyperpigmentation and overall photodamage was completed. Clinical assessment, tolerability measurements, and subject-assessments were performed baseline at Weeks 6, 8, and 12. Investigator Global Aesthetic Improvement Score was completed at Week 12.

Results

The eVCS-treated facial skin explants achieved a significant 145 percent collagen increase compared to control. The eVCS-RSB combination proved synergistic in reducing melanin compared to the eVCS alone. The eVCS-RSB combination demonstrated significant clinical improvement at all timepoints and was well tolerated. Subject responses were favorable and GAIS score of 3.0 was achieved at Week 12, indicating an improvement.

Limitations

Limitations include lack of placebo or vehicle control.

Conclusion

The product pairing, eVCS and RSB, offers patients an efficacious and well-tolerated treatment to target pigmentation and photodamage.

Clinical Trial

This study, Pro00050557, was approved by Advarra IRB (Columbia, Maryland) and submitted to ClinicalTrials.gov #: NCT05423873.

Clinical evaluation of a new fractional ablative 2910 nm erbium laser on photodamaged skin: A pilot study

OBJECTIVE

To examine the efficacy and safety of a new fractional, ablative erbium:glass fiber (Er:glass) laser (2910 nm) at improving clinical signs of photodamaged skin.

MATERIALS AND METHODS

Thirty-seven healthy participants aged 38-75 years with photodamaged skin were enrolled into two treatment groups. Group A (n = 14) received up to four laser treatments with mild settings, and focal facial subunits were treated with deeper settings. Group B (n = 23) received a single treatment using deeper settings. Following treatment, pain scores and severity and duration of skin responses (erythema, edema, and pinpoint bleeding) were assessed. Primary outcome was the improvement in participant and investigator Global Aesthetic Improvement Scale (GAIS) at 3-month follow-up. Secondary outcomes were participant satisfaction with treatment and whether they would repeat treatment.

RESULTS

Thirty-five participants completed the study (n = 1 lost to follow up in each group). Both groups had similar mean participant and investigator GAIS scores of 3/5 corresponding to "Improvement." All but two patients (both from Group A) reported improvement, satisfaction with treatment, and would repeat treatment. Posttreatment skin responses were mild-to-moderate, lasting up to 5 days. There was no scarring or dyspigmentation.

CONCLUSION

The 2910 nm Er:glass laser provided improvement in photoaging with high patient satisfaction.

Combining Diamond-Tip Dermabrasion Treatments and Topical Skincare in Participants with Dry, Hyperpigmented, Photodamaged or Acne-Prone/Oily Facial Skin: A Clinical Usage Study

Purpose

An in-office diamond tip microdermabrasion device (DG) was designed to simultaneously exfoliate, extract, and infuse topical cosmetic serums into the skin to improve its appearance. Combining in-office procedures with take-home skincare may enhance treatment outcomes. This study aimed to assess the efficacy of a novel combination of DG treatments with a take-home cosmetic skincare regimen (DGR) to address facial dryness, hyperpigmentation, photodamage, or acne-prone/oily skin.

Patients and Methods

In this 12-week, open-label, single-center study, participants were assigned to 1 of 4 groups according to skin presentation: dry, hyperpigmented, photodamaged, or acne-prone/oily. All participants received 6 bi-weekly DG treatments with tailored DGR topical products. During the DG treatment, the dry, hyperpigmented, photodamaged, and acne-prone/oily groups received hydrating, brightening, antioxidant, and pore-clarifying serums, respectively. Study endpoints included investigator grading, standardized photography, and participant questionnaires.

Results

Sixteen participants aged 22 to 70 years with Fitzpatrick Skin Types I-V completed the study. Immediately after the first DG treatment, significant improvements in dryness, radiance, texture, photodamage, and fine lines were achieved (P<0.01). At 72 hours, significant improvements were maintained in all these parameters except fine lines (P<0.05). The DG and DGR combination provided significant long-term improvements at week 12 compared to baseline for dryness, radiance, texture, hyperpigmentation, photodamage, skin tone unevenness, and periocular/perioral fine lines (P<0.05).

Conclusion

The combination of DG and DGR showed significant immediate and long-term improvements in skin appearance. These results show that the DG and DGR combination is a well-tolerated and effective intervention to enhance different aspects of facial skin quality.

Development of Modified Farquhar-von Caemmerer-Berry Model Describing Photodamage of Photosynthetic Electron Transport in C3 Plants under Different Temperatures

Photodamage of photosynthetic electron transport is a key mechanism of disruption of photosynthesis in plants under action of stressors. This means that investigation of photodamage is an important task for basic and applied investigations. However, its complex mechanisms restrict using experimental methods of investigation for this process; the development of mathematical models of photodamage and model-based analysis can be used for overcoming these restrictions. In the current work, we developed the modified Farquhar-von Caemmerer-Berry model which describes photodamage of photosynthetic electron transport in C3 plants. This model was parameterized on the basis of experimental results (using an example of pea plants). Analysis of the model showed that combined inactivation of linear electron flow and Rubisco could induce both increasing and decreasing photodamage at different magnitudes of inactivation of these processes. Simulation of photodamage under different temperatures and light intensities showed that simulated temperature dependences could be multi-phase; particularly, paradoxical increases in the thermal tolerance of photosynthetic electron transport could be observed under high temperatures (37-42 °C). Finally, it was shown that changes in temperature optimums of linear electron flow and Rubisco could modify temperature dependences of the final activity of photosynthetic electron transport under photodamage induction; however, these changes mainly stimulated its photodamage. Thus, our work provides a new theoretical tool for investigation of photodamage of photosynthetic processes in C3 plants and shows that this photodamage can be intricately dependent on parameters of changes in activities of linear electron flow and Rubisco including changes induced by temperature.

Obacunone Photoprotective Effects against Solar-Simulated Radiation-Induced Molecular Modifications in Primary Keratinocytes and Full-Thickness Human Skin

Solar radiation can cause damage to the skin, leading to various adverse effects such as sunburn, reactive oxygen species production, inflammation, DNA damage, and photoaging. To study the potential of photoprotective agents, full-thickness skin models are increasingly being used as in vitro tools. One promising approach to photoprotection involves targeting the redox-sensitive transcription factor Nrf2, which is responsible for regulating various cellular defense mechanisms, including the antioxidant response, inflammatory signaling, and DNA repair. Obacunone, a natural triterpenoid, has been identified as a potent Nrf2 agonist. The present study aims to evaluate the relevance of full-thickness (FT) skin models in photoprotection studies and to explore the potential photoprotective effects of obacunone on those models and in human keratinocytes. Phenion^® full-thickness skin models and keratinocytes were incubated with increasing concentrations of obacunone and irradiated with solar-simulated radiation (SSR). Various photodamage markers were evaluated, including histological integrity, oxidative stress, apoptosis, inflammation, photoaging-related dermal markers, and photocarcinogenesis markers. Increasing doses of SSR were found to modulate various biomarkers related to sun damage in the FT skin models. However, obacunone attenuated cytotoxicity, inflammation, oxidative stress, sunburn reaction, photoaging, and photocarcinogenesis in both keratinocytes and full thickness skin models exposed to SSR. These results suggest that obacunone may have potential as a photoprotective agent for preventing the harmful effects of solar radiation on the skin.

Efficacy of topical vitamin C in melasma and photoaging: A systematic review

BACKGROUND

Vitamin C is a micronutrient present in high concentrations in normal skin and a highly prescribed cosmeceutical, well known for protecting against ultraviolet-induced pigmentation and regulating collagen production. However, there is a lack of studies evaluating the efficacy of topical vitamin C in photoaging and melasma, with this systematic review being the first to assess the existing evidence.

AIM

This systematic review aims to assess whether topical vitamin C could be effective in reversing photoaging signs and treating melasma.

METHODS

Prospective, randomized controlled trials assessing protocols with topically applied vitamin C in patients with melasma or photodamage were searched in Medline, CENTRAL, and Scopus databases until the 12th of May 2022. Risk of bias was conducted in accordance with Cochrane Collaboration's tool for assessing the risk of bias in randomized trials, using RevMan 5.0.

RESULTS

Seven publications were included, with 139 volunteers in total. Studies that evaluated the topography of skin indicated that the treated skin appeared smoother and less wrinkled, which was supported by biopsies data. On objective assessments of pigmentation, there was a significant lightening of the skin treated. Hydration improved equally in the vitamin C and placebo-treated sites.

CONCLUSIONS

This study revealed that vitamin C is effective in treating uneven, wrinkled skin and has depigmenting properties, but long-term use may be needed to achieve noticeable changes. Q-switched Nd:YAG laser-associated protocols appear beneficial in enhancing vitamin C effects. Topical vitamin C may be a suitable alternative for melasma and photoaging, but more studies are needed to confirm these results and assess the ideal vitamin C concentration.

MURIN: Multimodal Retinal Imaging and Navigated-laser-delivery for dynamic and longitudinal tracking of photodamage in murine models

Laser-induced photodamage is a robust method for investigating retinal pathologies in small animals. However, aiming of the photocoagulation laser is often limited by manual alignment and lacks real-time feedback on lesion location and severity. Here, we demonstrate a multimodality OCT and SLO ophthalmic imaging system with an image-guided scanning laser lesioning module optimized for the murine retina. The proposed system enables targeting of focal and extended area lesions under OCT guidance to benefit visualization of photodamage response and the precision and repeatability of laser lesion models of retinal injury.

Investigating the efficacy of a fractionated 1927 nm laser for diffuse dyspigmentation and actinic changes

OBJECTIVES

Facial actinic irregularities are frequent targets for noninvasive, energy-based treatment. These irregularities are multifactorial and driven by both intrinsic factors such as aging, genetics, and hormone exposure, and extrinsic factors, such as UV exposure. Clinically, this photodamage manifests as dyschromic skin disorders like melasma and actinic features such as solar lentigines. Fractionated 1927 nm (f1927 nm) nonablative lasers are suitable for targeting epidermal lesions and have been shown to be effective in resurfacing photoaged skin as well as addressing pigmented lesions without exacerbation. The purpose of this study was to quantify the magnitude and duration of actinic pigment and photodamage response in patients of Fitzpatrick Skin Phototypes (SPT) I-IV who underwent two treatments with a fractionated, nonablative 1927 nm thulium laser (MOXI™, Sciton).

METHODS

The authors conducted an IRB-approved, single-center, prospective, nonrandomized study to evaluate the efficacy of f1927 nm nonablative lasers in the treatment of diffuse dyspigmentation and actinic irregularities. Patients underwent two treatments with f1927 nm nonablative laser at a 1-month interval. F1927 nm treatment and energy parameters included a pulse energy of 15 mJ, density of 15% with 15% coverage, and six total passes. The primary endpoint for this study was pigment response after treatment, measured using the VISIA Skin Imaging and Analysis System (Canfield Scientific). Pigmentary lesions measured and analyzed included spots, UV spots, and brown spots. The Physician's Global Assessment Scale was used by plastic surgeons to provide a subjective clinical assessment of melasma response. Nonparametric testing was used to assess and compare VISIA results across the study period as well as clinician evaluations. A p value ≤ 0.05 was considered statistically significant.

RESULTS

Twenty-seven patients underwent two treatments with nonablative, f1927 nm laser in May and June 2022. Ninety-six percent of patients (n = 26) completed 1-month follow-up and 89% of patients (n = 24) completed 3-month follow-up. The study cohort was 100% female, with a mean ± SD age of 47.0 ± 11.5 (range: 29-74), and a mean Fitzpatrick SPT of 2.8 (range: I-IV). No serious adverse events were observed during study treatment or follow-up. Overall, analysis showed statistically significant improvements in dyspigmentation at 1 month and an increase in pigment toward baseline at 3 months. At 1 month, there was a statistically significant decrease in spots (p = 0.002), UV spots (p < 0.001), and brown spots (p < 0.001) compared to baseline. At 3 months, Brown spots remained significantly improved compared to baseline (p = 0.05). Analysis showed 9.9% improvement in pigment on the left (p < 0.0001) and 7.5% improvement in pigment on the right (p < 0.0001) face. Right dyspigmentation remained significantly improved at 3-month follow-up (p = 0.02). Subjectively, clinician evaluators' mean Physician's Global Assessment Scale score was 3.4 (p < 0.0001) at 1-month follow-up and 3.7 (p < 0.0001) at 3-month follow-up, which correspond to an approximately 50% improvement hyperpigmentation when at both time points.

CONCLUSION

These results demonstrate that fractionated, nonablative 1927 nm laser treatment is an effective modality for improving clinical and subclinical photodamage. The magnitude and duration of pigment improvement are potentially influenced by the propensity for photodamage during the summer months, which may suggest the need for multiple f1927 nm treatments over time to maintain results.

Maslinic acid attenuates UVB-induced oxidative damage in HFF-1 cells

BACKGROUND

Oxidative damage is one of the major mechanisms of ultraviolet B (UVB)-induced damage to the skin. Maslinic acid (MA) is a natural compound of pentacyclic triterpene acids. It has been proved to have anti-inflammatory and antioxidant properties.

OBJECTIVE

This study aimed to explore the effects of MA on oxidative damage in human foreskin fibroblast cells (HFF-1) and the potential molecular mechanisms.

METHODS

A specific dose of UVB radiation was used to induce oxidative damage in HFF-1. Based on this, we performed measurements of cell proliferation, reactive oxygen species (ROS) levels, antioxidant enzyme activity, inflammation-related mediators, and NF-κB nuclear localization with or without the addition of MA.

RESULTS

MA significantly promoted cell proliferation viability at 10 and 20 μM. The addition of MA 24 h before UVB irradiation was more effective at enhancing cell proliferation and also produced lower ROS levels compared to co-cultured fibroblasts and MA for 24 h after irradiation. However, there was no statistically significant difference between groups at concentrations of 10 and 20 μM. The pretreatment group with MA had elevated superoxide dismutase and catalase activities, decreased IL-6 generation, and lowered mRNA levels of IL-6, TNF-α and MMP3 in comparison with the UVB-irradiated group without additional MA. Meanwhile, the nuclear translocation of NF-κB and the degradation of IκB were inhibited by MA pretreatment.

CONCLUSION

Taken together, these findings suggest that MA may alleviate UVB-induced oxidative damage in HFF-1 by inhibiting the nuclear translocation of NF-κB.

Inflammatory stimulus worsens the effects of UV-A exposure on J774 cells

UV-A radiation affects skin homeostasis by promoting oxidative distress. Endogenous photosensitizers in the dermis and epidermis of human skin absorb UV-A radiation forming excited states (singlet and triplet) and reactive oxygen species (ROS) producing oxidized compounds that trigger biological responses. The activation of NF-kB induces the expression of pro-inflammatory cytokines and can intensify the generation of ROS. However, there is no studies evaluating the cross talks between inflammatory stimulus and UV-A exposure on the levels of redox misbalance and inflammation. In here, we evaluated the effects of UV-A exposure on J774 macrophage cells previously challenged with LPS in terms of oxidative distress, release of pro-inflammatory cytokines, and activation of regulated cell death pathways. Our results showed that LPS potentiates the dose-dependent UV-A-induced oxidative distress and cytokine release, in addition to amplifying the regulated (autophagy and apoptosis) and non-regulated (necrosis) mechanisms of cell death, indicating that a previous inflammatory stimulus potentiates UV-A-induced cell damage. We discuss these results in terms of the current-available skin care strategies.

Enhancement of Human Epidermal Cell Defense against UVB Damage by Fermentation of Passiflora edulis Sims Peel with Saccharomyces cerevisiae

The processing of Passiflora edulis Sims results in large amounts of wasted peel resources and environmental pollution. In order to improve the utilisation of natural plant resources and economic benefits, this study uses Saccharomyces cerevisiae to ferment Passiflora edulis Sims peel to obtain Passiflora edulis Sims peel fermentation broth (PF). The content of active substances in unfermented Passiflora edulis Sims peel water extract (PW) and PF is then determined, as well as their in vitro antioxidant capacity. The protective effects of PF and PW on UVB-induced skin inflammation and skin barrier damage in human immortalised epidermal keratinocytes (HaCaT) cells (including cell viability, ROS, HO-1, NQO1, IL-1β, IL-8, TNF-α, KLK-7, FLG, AQP3 and Caspase 14 levels) are investigated. Studies have shown that PF enhances the content of active substances more effectively compared to PW, showing a superior ability to scavenge free radical scavenging and antioxidants. PW and PF can effectively scavenge excess intracellular ROS, reduce the cellular secretion of pro-inflammatory factors, regulate the content of skin barrier-related proteins and possibly respond to UVB-induced cell damage by inhibiting the activation of the PI3K/AKT/mTOR signalling pathway. Studies have shown that both PW and PF are safe and non-irritating, with PF exploiting the efficacy of Passiflora edulis Sims peel more significantly, providing a superior process for the utilisation of Passiflora edulis Sims waste. At the same time, PF can be developed and used as a functional protective agent against ultraviolet damage to the skin, thereby increasing the value of the use of Passiflora edulis Sims waste.

The effect of tomato and lycopene on clinical characteristics and molecular markers of UV-induced skin deterioration: A systematic review and meta-analysis of intervention trials

Lycopene as a natural antioxidant that have been studied for ultraviolet radiation (UVR) photo protection and is one of the most effective carotenoids to scavenge reactive oxygen species (ROS). This review aims to summarize the protective effect of tomato and lycopene on skin photo damage and skin photoaging in healthy subjects by reviewing the existing population intervention experiments. A total of five electronic databases including PubMed, Scopus, EBSCO, Web of Science and Cochrane Library were searched from inceptions to January 2021 without any restriction. Out of 19336 publications identified, 21 fulfilled the inclusion criteria and were meta-analysis. Overall, interventions supplementing tomato and lycopene were associated with significant reductions in Δa*, MMP-1, ICAM-1 and skin pigmentation; while tomato and lycopene supplementation were associated with significant increase in MED, skin thickness and skin density. Based on the results of this systematic review and meta-analysis, supplementation with tomato and lycopene could reduce skin erythema formation and improve the appearance and pigmentation of the skin, thereby preventing light-induced skin photodamage and skin photoaging. Lycopene-rich products could be used as endogenous sun protection and may be a potential nutraceutical for sun protection.

Repeated exposure to fractional CO2 laser delays squamous cell carcinoma formation and prevents clinical and subclinical photodamage visualized by line-field confocal optical coherence tomography and histology

OBJECTIVES

Ablative fractional laser (AFL) is a well-established modality for treating ultraviolet radiation (UVR)-induced skin photodamage. We aimed to investigate the potential of AFL to delay squamous cell carcinoma (SCC) formation and prevent photodamage in a preclinical UVR-induced SCC model.

MATERIALS AND METHODS

Hairless C3.Cg-Hrhr /TifBomTac mice (n = 50) were exposed to UVR three times weekly throughout the study. UV-exposed mice were randomized to two groups that received dorsal CO2 AFL (10 mJ/mb, 10% density) or no treatment. AFL was performed every other week for a total of 16 weeks (nine treatments in total). The primary outcome was time to tumor occurrence. In a subset of mice on Day 150, prevention of clinical photodamage was assessed by examination of skin tightness and dyspigmentation. Concomitantly, assessment of subclinical photoprevention based on normalization of keratinocyte dysplasia, dermo-fiber morphology (collagen and elastin fibers), and skin thickness, was performed using line-field confocal optical coherence tomography (LC-OCT) and histology.

RESULTS

Repeated AFL treatments delayed SCC tumor development compared to UVR control mice by 12, 19, and 30 days for first, second, and third tumors, respectively (p ≤ 0.0017). Compared to UVR controls, AFL prevented photodamage both clinically and subclinically, based on LC-OCT and histology. In the epidermal layer, AFL imparted photopreventative effects including reduced dyspigmentation and keratinocyte dysplasia (1 vs. 2.5, p = 0.0079) and partial normalization of the epidermal thickness (p < 0.0001). In the dermis, AFL led to twofold greater skin tightness (p = 0.0079), improved dermo-fiber structure, and dermal thickness (p = 0.0011).

CONCLUSION

In conclusion, repeated AFL treatments of UVR-exposed skin significantly delayed SCC tumor formation and prevented clinical and imaging-assessed subclinical signs of photodamage, indicating a potential for AFL in prevention strategies for SCC and photodamage in high-risk populations.

Improvements in skin quality parameters in postmenopausal participants after use of topical growth factor serum

BACKGROUND

Photodamage can induce skin aging processes that can be particularly concerning for postmenopausal women. Growth factors from hypoxic human fibroblast-conditioned media have demonstrated improvements in skin quality parameters.

AIMS

The aim of the study was to assess efficacy and tolerability of topical combination-treatment hypoxic growth factor serum (TNS A+) in postmenopausal women with moderate to severe facial photodamage.

PATIENTS/METHODS

In this 12-week, open-label, single-center study, participants used TNS A+ serum twice daily. Postmenopausal women (40-65 years of age) with Fitzpatrick skin types I-VI and modified Griffiths scale scores 4-9 were eligible. Clinical and participant-reported assessments were evaluated at Weeks 6 and 12. Statistical significance was defined as p ≤ 0.05.

RESULTS

There were 17 enrolled participants. TNS A+ treatment demonstrated significant improvements from baseline in fine lines and wrinkles in periocular, forehead, and cheek areas at Week 12 and the perioral area at Weeks 6 and 12. Significant improvements from baseline in coarse lines and wrinkles were observed for the perioral area at Week 12 and periocular and cheek areas at Weeks 6 and 12. Improvements in overall photodamage, skin tone evenness, and tactile roughness were significantly greater at Weeks 6 and 12 versus baseline. Most participants reported TNS A+ made their skin look and feel smooth, soft, and rejuvenated; improved skin radiance; made lines and wrinkles less apparent; and improved skin texture. No treatment-related adverse events were reported.

CONCLUSIONS

The TNS A+ regimen was well tolerated and provided significant improvements in skin quality in postmenopausal women with moderate to severe facial photodamage.

Singlet oxygen production by photosystem II is caused by misses of the oxygen evolving complex

Singlet oxygen (¹ O₂ ) is a harmful species that functions also as a signaling molecule. In chloroplasts, ¹ O₂ is produced via charge recombination reactions in photosystem II, but which recombination pathway(s) produce triplet Chl and ¹ O₂ remains open. Furthermore, the role of ¹ O₂ in photoinhibition is not clear. We compared temperature dependences of ¹ O₂ production, photoinhibition, and recombination pathways. ¹ O₂ production by pumpkin thylakoids increased from -2 to +35°C, ruling out recombination of the primary charge pair as a main contributor. S₂ Q_A ^- or S₂ Q_B ^- recombination pathways, in turn, had too steep temperature dependences. Instead, the temperature dependence of ¹ O₂ production matched that of misses (failures of the oxygen (O₂ ) evolving complex to advance an S-state). Photoinhibition in vitro and in vivo (also in Synechocystis), and in the presence or absence of O₂ , had the same temperature dependence, but ultraviolet (UV)-radiation-caused photoinhibition showed a weaker temperature response. We suggest that the miss-associated recombination of P₆₈₀ ⁺ Q_A ^- is the main producer of ¹ O₂ . Our results indicate three parallel photoinhibition mechanisms. The manganese mechanism dominates in UV radiation but also functions in white light. Mechanisms that depend on light absorption by Chls, having ¹ O₂ or long-lived P₆₈₀ ⁺ as damaging agents, dominate in red light.

A Scoping Review on the Effects of Carotenoids and Flavonoids on Skin Damage Due to Ultraviolet Radiation

Skin exposure to ultraviolet (UV) rays in the sun causes premature ageing and may predispose to skin cancers. UV radiation generates excessive free radical species, resulting in oxidative stress, which is responsible for cellular and DNA damage. There is growing evidence that phytonutrients such as flavonoids and carotenoids may impede oxidative stress and prevent photodamage. We conducted a systematic review of the literature to explore the effects of certain phytonutrients in preventing skin photodamage. We searched the electronic Medline (Ovid) and Pubmed databases for relevant studies published between 2002 and 2022. The main inclusion criteria were articles written in English, and studies reporting the effects of phytonutrient-containing plants of interest on the skin or skin cells exposed to UV radiation. We focused on tea, blueberries, lemon, carrot, tomato, and grapes, which are rich in flavonoids and/or carotenoids. Out of 434 articles retrieved, 40 were identified as potentially relevant. Based on our inclusion criteria, nine articles were included in the review. The review comprises three combined in vitro and animal studies, four human studies, one in vitro research, and one mixed in vitro and human study. All the studies reported positive effects of flavonoids and carotenoid-containing plant extract on UV-induced skin damage. This evidence-based review highlights the potential use of flavonoids and carotenoids found in plants in preventing the deleterious effects of UV radiation on the skin. These compounds may have a role in clinical and aesthetic applications for the prevention and treatment of sunburn and photoaging, and may potentially be used against UV-related skin cancers.

The Arabidopsis NLP7-HB52/54-VAR2 pathway modulates energy utilization in diverse light and nitrogen conditions

In plants, nitrate is the dominant nitrogen (N) source and a critical nutrient signal regulating various physiological and developmental processes.^1,2,3,4 Nitrate-responsive gene regulatory networks are widely believed to control growth, development, and life cycle in addition to N acquisition and utilization,^1,2,3,4 and NIN-LIKE PROTEIN (NLP) transcriptional activators have been identified as the master regulators governing the networks.^5,6,7 However, it remains to be elucidated how nitrate signaling regulates respective physiological and developmental processes. Here, we have identified a new nitrate-activated transcriptional cascade involved in chloroplast development and the maintenance of chloroplast function in Arabidopsis. This cascade consisting of NLP7 and two homeodomain-leucine zipper (HD-Zip) class I transcription factors, HOMEOBOX PROTEIN52 (HB52) and HB54,^8,9 was responsible for nitrate- and light-dependent expression of VAR2 encoding the FtsH2 subunit of the chloroplast FtsH protease involved in the quality control of photodamaged thylakoid membrane proteins.^10,11 Consistently, the nitrate-activated NLP7-HB52/54-VAR2 pathway underpinned photosynthetic light energy utilization, especially in high light environments. Furthermore, genetically enhancing the NLP7-HB52/54-VAR2 pathway resulted in improved light energy utilization under high light and low N conditions, a superior agronomic trait. These findings shed light on a new role of nitrate signaling and a novel mechanism for integrating information on N nutrient and light environments, providing a hint for enhancing the light energy utilization of plants in low N environments.

Limonene protects human skin keratinocytes against UVB-induced photodamage and photoaging by activating the Nrf2-dependent antioxidant defense system

Long term exposure to solar ultraviolet B (UVB) radiation is one of the primary factors of premature skin aging and is referred to as photoaging. Also, mammalian skin exposed to UVB triggers an increase in production of α-melanocyte-stimulating hormone (α-MSH), which is critically involved in the pathogenesis of hyperpigmentary skin diseases. This study investigated the protective effect of limonene on UVB-induced photodamage and photoaging in immortalized human skin keratinocytes (HaCaT) in vitro. Initially, we determined cell viability and levels of reactive oxygen species (ROS) in UVB-irradiated HaCaT cells. Pretreatment with limonene increased cell viability followed by inhibition of intracellular ROS generation in UVB-irradiated HaCaT cells. Interestingly, the antioxidative activity of limonene was directly correlated with an increase in expression of endogenous antioxidants, including heme oxygenase 1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO-1), and γ-glutamylcysteine synthetase (γ-GCLC), which was associated with enhanced nuclear translocation and activation of NF-E2-related factor-2 (Nrf2). Indeed, Nrf2 knockdown reduced limonene's protective effects. Additionally, we observed that limonene treatment inhibited UVB-induced α-MSH secretion followed by inhibition of proopiomelanocortin (POMC) via suppression of p53 transcriptional activation. Moreover, limonene prevented UVB-mediated depletion of tight junction regulatory proteins, including occludin and zonula occludens-1. On the other hand, limonene treatment significantly decreased matrix metalloproteinase-2 levels in UVB-irradiated HaCaT cells. Based on these results, limonene may have a dermato-protective effect in skin cells by activating the Nrf2-dependent cellular antioxidant defense system.

Multifaceted amelioration of cutaneous photoageing by (0.3%) retinol

BACKGROUND

Although retinol skin care products improve the appearance of photoaged skin, there is a need for an effective retinol concentration that provides skin benefits without irritation.

OBJECTIVE

To compare the efficacy of topical 0.1%, 0.3% and 1% retinol in remodelling the cutaneous architecture in an in vivo experimental patch test study, and to determine tolerance of the most effective formulations when used in a daily in-use escalation study.

METHODS

For the patch test study, retinol products were applied under occlusion, to the extensor forearm of photoaged volunteers (n = 5; age range 66-84 years), and 3 mm skin biopsies obtained after 12 days. Effects of different retinol concentrations, and a vehicle control, on key epidermal and dermal biomarkers of cellular proliferation and dermal remodelling were compared to untreated baseline. Separately, participants (n = 218) recorded their tolerance to 0.3% or 1% retinol over a six-week, approved regimen, which gradually increased the facial applications to once nightly.

RESULTS

Retinol treatment induced a stepwise increase in epidermal thickness and induced the expression of stratum corneum proteins, filaggrin and KPRP. 0.3% retinol and 1% retinol were comparably effective at inducing keratinocyte proliferation in the epidermis, whilst reducing e-cadherin expression. Fibrillin-rich microfibril deposition was increased following treatment with 0.3% and 1% retinol (p < 0.01); other dermal components remained unaltered (e.g., fibronectin, collagen fibrils, elastin), and no evidence of local inflammation was detected. The in-use study found that 0.3% retinol was better tolerated than 1% retinol, with fewer and milder adverse events reported (χ² (1) = 23.97; p < 0.001).

CONCLUSIONS

This study suggests that 1% and 0.3% retinol concentrations were similarly effective at remodelling photodamaged skin in an in vivo model of long-term use. Use of 0.3% retinol in the escalation study was associated with fewer adverse reactions when applied daily. Hence, 0.3% retinol may be better tolerated than 1% retinol, thereby allowing longer-term topical application.

Hesperetin attenuates UVA-induced photodamage in human dermal fibroblast cells

BACKGROUND

Ultraviolet A (UVA) radiation causes skin damage. Recently, natural compounds have become an interest to protect skin from UV-induced photodamages.

METHODS

In this study, we investigated the protective effects of hesperetin, a citrus flavonoid, on UVA-induced oxidative stress, inflammation, apoptosis, and photoaging.

RESULTS

Our results showed that hesperetin increased the cell viability, suppressed the intracellular ROS levels, and decreased the expression of MMPs including MMP-1 and MMP-3, pro-inflammatory cytokines including IL-6 and COX-2 in UVA-irradiated HDFs. Besides, hesperetin exerted an anti-apoptotic effect by increasing expression of anti-apoptotic protein Bcl-2 and decreasing expression of pro-apoptotic protein Bax. Moreover, these anti-photodamage effects were mediated by inhibition of ERK, p38/AP-1, and NF-κb/p65 phosphorylation.

CONCLUSION

Therefore, hesperetin may be useful in the prevention of UVA-induced skin damage.

Two Laminaria japonica Fermentation Broths Alleviate Oxidative Stress and Inflammatory Response Caused by UVB Damage: Photoprotective and Reparative Effects

UVB radiation can induce oxidative stress and inflammatory response in human epidermal cells. We establish a UVB-induced damage model of human immortalized epidermal keratinocytes (HaCaT) to explore the protective and reparative effects of Laminaria japonica on UVB-damaged epidermal inflammation after fermentation by white Ganoderma lucidum (Curtis) P. Karst and Saccharomyces cerevisiae. Compared with unfermented Laminaria japonica, fermented Laminaria japonica possesses stronger in vitro free radical scavenging ability. Laminaria japonica white Ganoderma lucidum fermentation broth (LJ-G) and Laminaria japonica rice wine yeast fermentation broth (LJ-Y) can more effectively remove excess reactive oxygen species (ROS) in cells and increase the content of the intracellular antioxidant enzymes heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO-1). In addition, fermented Laminaria japonica effectively reduces the content of pro-inflammatory factors ILs, TNF-α and MMP-9 secreted by cells. The molecular research results show that fermented Laminaria japonica activates the Nrf2 signaling pathway, increases the synthesis of antioxidant enzymes, inhibits the gene expression levels of pro-inflammatory factors, and alleviates cellular oxidative stress and inflammatory response caused by UVB radiation. Based on the above results, we conclude that fermented Laminaria japonica has stronger antioxidant and anti-inflammatory activity than unfermented Laminaria japonica, possesses good safety, and can be developed and used as a functional inflammation reliever. Fermented Laminaria japonica polysaccharide has a more slender morphological structure and more rockulose, with better moisturizing and rheological properties.

Photoprotective Effects of Cannabidiol against Ultraviolet-B-Induced DNA Damage and Autophagy in Human Keratinocyte Cells and Mouse Skin Tissue

Cannabidiol (CBD) has emerged as a phytocannabinoid with various beneficial effects for the skin, including anti-photoaging effects, but its mechanisms of action are not fully elucidated. The study assessed CBD’s photoprotective effects against acute ultraviolet B (UVB)-induced damage in HaCaT human keratinocyte cells and murine skin tissue. CBD (8 μM) alleviated UVB-induced cytotoxicity, apoptosis, and G2/M cell cycle arrest in HaCaT cells. The contents of γH2AX and cyclobutane pyrimidine dimers were decreased after CBD treatment. CBD reduced the production of reactive oxygen species and modulated the expression of antioxidant-related proteins such as nuclear factor erythroid 2-related factor 2 in UVB-stimulated HaCaT cells. Furthermore, CBD mitigated the UVB-induced cytotoxicity by activating autophagy. In addition, a cream containing 5% CBD showed effectiveness against UVB-induced photodamage in a murine model. The CBD cream improved the skin’s condition by lowering the photodamage scores, reducing abnormal skin proliferation, and decreasing expression of the inflammation-related protein cyclooxygenase-2 in UVB-irradiated skin tissue. These findings indicate that CBD might be beneficial in alleviating UVB-induced skin damage in humans. The photoprotective effects of CBD might be attributed to its modulatory effects on redox homeostasis and autophagy.

Anti-Melanogenesis and Photoprotective Effects of Ecklonia maxima Extract Containing Dieckol and Eckmaxol

Seaweeds are potential ingredients in the cosmeceutical industry. Our previous study demonstrates that the phlorotannin-enriched extract of Ecklonia maxima (EME-EA) containing dieckol and eckmaxol possesses strong anti-inflammatory activity and suggests the cosmeceutical potential of EME-EA. In order to evaluate the cosmeceutical potential of EME-EA, the anti-melanogenesis and photoprotective effects of EME-EA were investigated in this study. EME-EA remarkably inhibited mushroom tyrosinase and melanogenesis in alpha-melanocyte-stimulating hormone-stimulated B16F10 cells. In addition, EME-EA significantly suppressed UVB-induced HaCaT cell death that was consistent with inhibition of apoptosis and reduction in scavenging intracellular reactive oxygen species. Furthermore, EME-EA significantly inhibited collagen degradation and matrix metalloproteinases expression in UVB-irradiated HDF cells in a concentration-dependent manner. These results indicate that EME-EA possesses strong anti-melanogenesis and photoprotective activities and suggest EME-EA is an ideal ingredient in the pharmaceutical and cosmeceutical industries.

Assessing changes in facial skin quality using noninvasive in vivo clinical skin imaging techniques after use of a topical retinoid product in subjects with moderate-to-severe photodamage

BACKGROUND

Studies utilizing reflectance confocal microscopy (RCM) and dynamic optical coherence tomography (D-OCT) to assess cosmetic skin changes are limited.

METHODS

A 12-week, open-label study was conducted using RCM and D-OCT to evaluate the effects of a topical cosmetic retinol (RET05) on subjects with facial photodamage. Study endpoints included investigator grading, standardized (VISIA-CR) and 3D photography (Antera 3D), independent RCM (VivaScope1500) and D-OCT (VivoSight) image analysis, validated FACE-Q scales, and subject questionnaires.

RESULTS

Twenty-three subjects, 45- to 68-year old, with Fitzpatrick skin types II-IV completed the study. After 12 weeks of repeated application, RET05 demonstrated significant corresponding cosmetic improvements for overall photodamage, skin tone unevenness, tactile roughness, fine lines/wrinkles (forehead, periocular, and perioral), and coarse lines/wrinkles (forehead, periocular, and cheeks), and Allergan Skin Roughness Scale. FACE-Q assessments also demonstrated significant improvements from baseline at week 12. RCM analysis showed decreases in all epidermis, less compact stratum corneum (SC), more non-compact SC, decreases in coarse/huddled dermal fibers, and increases in fibrillar dermal fibers, as compared to baseline. D-OCT analysis showed significant decreases in epidermal thickness (ET), reduction of moderate/many collagen fragments and collagen bundles, and significant increases in the stroma attenuation coefficient and collagen density. Moreover, the dermal-epidermal junction was more pronounced, and vascular abundance at 300 and 500 μm depth increased. Independent evaluation of RCM and D-OCT images showed similar decreases in ET and improvements in dermal fibers.

CONCLUSION

This study was the first to utilize RCM and D-OCT to evaluate the cosmetic effects of a topical retinoid and further substantiate improvements in skin quality.

Hydrogen sulfide protects retina from blue light-induced photodamage and degeneration via inhibiting ROS-mediated ER stress-CHOP apoptosis signal

Background: Hydrogen sulfide (H₂S) is a small reducing gas molecule with various biological functions such as anti-oxidative, anti-apoptotic and anti-inflammatory activities. In this study, we investigated the therapeutic effects of exogenous H₂S in the experimental models of retinal photodamage in vivo and in vitro.

Methods: Rats with open eyelids were pretreated with H₂S (80~120 μmol/kg) for 10 days and then continuously exposed to blue light (435~445nm, 11.2W/m2) for 8 h to establish in vivo experimental model. ARPE-19 cells were pretreated with H₂S and then exposed to blue light to establish in vitro experimental model.

Results: In vivo experiments, H₂S significantly ameliorated blue light-induced retinal oxidative stress, apoptosis and degeneration. Moreover, H₂S inhibited the activation of blue light-induced endoplasmic reticulum (ER) stress CHOP apoptotic signaling. In vitro experiments, H₂S improved blue light-induced oxidative stress and oxidative damage. H₂S inhibited ROS-mediated activation of ER stress CHOP apoptotic signaling. H₂S alleviated blue light-induced apoptosis and increases cell viability. The ER stress inhibitor 4-PBA alleviated blue light-induced apoptosis and increases cell viability.

Conclusion: Taken together, these results indicate that H₂S can inhibit ROS-mediated ER stress-CHOP apoptosis signal, thereby alleviating blue light-triggered retinal apoptosis and degeneration.

HSP27 Protects Skin From Ultraviolet B -Induced Photodamage by Regulating Autophagy and Reactive Oxygen Species Production

Ultraviolet (UV) irradiation has been well documented to be linked with almost all skin problems we know, and both dermis and epidermis may be affected to varying degrees by UV irradiation. Every time when exposed to sunlight without protection, our skin will step closer to photoaging, leading to irreversible consequences ultimately. Heat shock protein 27 (HSP27) is a vital protein involved in cell growth, autophagy, apoptosis, drug resistance, tumor genesis and metastasis. Evidence suggests that the organism is subjected to various internal and external environmental stresses (heat, oxidative stress, organic toxicants, etc.), and HSP27 with high expression has protective function. However, the expression of HSP27 in coping with UV irradiation have not been examined thoroughly. In this study, photodamage models were developed through different doses of UVB irradiation in human epidermal keratinocytes (HEKs) (30 mJ/cm²), human dermal fibroblasts (HDFs) (150 mJ/cm²) and mouse skin (2,700 mJ/cm²). HSP27 knockdown decreased cell viability and increased the incidence of UVB-induced reactive oxygen species (ROS) production. We got consistent results in vivo and vitro. Compared with that in the UVB group, the expression of LC3B was significantly lower, while the expression of p62 was significantly higher in the UVB + si-HSP27 group. It was also revealed that HSP27 knockdown reduced the expressions of some antioxidants, such as superoxide dismutase (SOD) and catalase (CAT), which accelerated UVB-induced ROS release. Moreover, histological results showed that epidermis was thickened and collagen fibers were disorganized in the UVB + si-HSP27 group. These findings have demonstrated that HSP27 might play a photoprotective role in the UVB-induced skin damage process by maintaining the normal autophagy and antioxidant level. It is implied that HSP27 could be a potential therapeutic target of photodamage. However, determination of the definitive mechanism requires further exploration.

The effect of all-trans retinoic acid on the mitochondrial function and survival of cardiomyoblasts exposed to local photodamage

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Prospective study of intense pulsed light versus pulsed dye laser with or without blue light in the activation of PDT for the treatment of actinic keratosis and photodamage

BACKGROUND

Exposure to ultraviolet (UV) light from the sun is known to have a deleterious effect on the skin. Repeated insults to the dermal matrix from UV radiation result in the clinical signs of photodamage, including changes in skin elasticity, color, and texture. UV radiation also leads to the accumulation of DNA mutations and promotes tumor development, resulting in the formation of cutaneous precancerous and cancerous lesions. Continuous-wave incoherent blue light, intense pulsed light (IPL), and pulsed dye laser (PDL) are safe and efficacious light sources commonly used for aminolevulinic acid photodynamic therapy (PDT). The aim of this study was to prospectively evaluate the efficacy of PDT for the treatment of photodamage and actinic keratoses using four different combinations of light sources: PDL, PDL + blue light, IPL, and IPL + blue light.

STUDY

A total of 220 patients with either photodamage or actinic keratosis (AK) were recruited from the Miami Dermatology Laser Institute (Miami, FL) and were assigned prospectively to undergo one PDT treatment with one of the four light options: PDL, PDL + blue light, IPL or IPL + blue light. Of the 220 patients enrolled in treatment groups, 214 patients completed the study. Of the 214 patients, 88 received treatment for AK, and 126 received treatment for photodamage. All patients gave their consent to participate in the study and to allow their photographs to be utilized for the purpose of scientific presentations.

RESULTS

Treatment with IPL resulted in a 70.8% reduction of actinic keratoses at a 1-month follow-up. Treatment with IPL and blue light 84.4% reduction of actinic keratoses at 1 month follow up. Treatment with PDL 70.5% reduction of actinic keratoses at 1 month follow up. Treatment with PDL and blue light 69.3% reduction of actinic keratoses at 1 month follow up. Treatment with IPL resulted in an improvement score of 2.9. Treatment with IPL and blue light resulted in an improvement score of 3.0. Treatment PDL resulted in an improvement score of 1.5. Treatment with PDL and blue light resulted in an improvement score of 1.8.

CONCLUSION

Although all four treatment groups led to some improvement in signs of photoaging, IPL + blue light again demonstrated increased efficacy when compared to IPL, PDL, and PDL + blue light treatment groups. Results from our study were limited by an unequal distribution between treatment groups and a lack of follow-up beyond a 1-month period and warrant further research.

The effect of a dual-wavelength 532 nm and 1064 nm picosecond-domain laser with a fractionated holographic optic on photoaging and patient age perception: A pilot study

INTRODUCTION

This study evaluated the efficacy of a dual-wavelength 532 nm/1064 nm Nd:YAG picosecond-domain laser with a holographic lens array in treating facial photoaging.

METHODS

Thirteen subjects were enrolled with 10 completing the study. Receiving three-month treatments, subjects underwent full-face spot treatment of facial lentigines with the 532-nm non-fractionated handpiece, followed by two sequential facial passes of the 1064-nm and the 532-nm fractionated handpieces. Improvement was measured by treating physician evaluation of pigmentation and rhytids as well as blinded reviewer evaluation of pre- and post-treatment image sets taken 12 weeks after the final treatment. Participants completed treatment surveys to assess satisfaction.

RESULTS

Physician grading on a 5-point scale revealed an average improvement of 1.6 in pigmentation (p = 0.0042) and 0.9 in rhytids (p = 0.0196). Blinded physicians appropriately selected baseline images in 44 of 50 (88%) image sets (10 subjects; five reviewers). On an 11-point scale for overall facial photoaging (0 = no change, 1 = 10% improvement, 2 = 20% improvement, etc.) treating physicians scored mean improvement as 3.3 ± 1.83 (95% CI 1.99 to 4.61; range 1-6), while blinded reviewers scored mean improvement as 2.32 ± 2.62 (range % -4 to 8, 95% CI 1.57 to 3.07). The greatest majority (80%) of participants reported satisfaction with the treatment. Adverse events were mild; however, one patient developed hyperpigmentation, consistent with melasma that was successfully treated with topical agents.

CONCLUSION

This is the first study to show that picosecond-domain 532 nm/1064 nm laser treatments with combination non-fractionated and fractionated handpieces are well-tolerated, safe, and effective for the treatment of photodamage.

Research progress on skin photoaging and oxidative stress

Skin photoaging, which is a kind of exogenous aging, refers to skin elasticity degradation, skin roughening, and wrinkle formation processes because of cascading reactions of a series of kinases after growth factor receptors and cytokine receptors are activated on a cell surface under the UV effect. An extensively recognized skin photoaging mechanism is free radical-oxidative stress concept, proposed by Sohal who represents the authority of the US aging studies. Over the past decade, many new developments in the oxidative stress mechanism have been achieved in terms of the occurrence, development, prevention, and treatment of photodamage.

Light potentials of photosynthetic energy storage in the field: what limits the ability to use or dissipate rapidly increased light energy?

The responses of plant photosynthesis to rapid fluctuations in environmental conditions are critical for efficient conversion of light energy. These responses are not well-seen laboratory conditions and are difficult to probe in field environments. We demonstrate an open science approach to this problem that combines multifaceted measurements of photosynthesis and environmental conditions, and an unsupervised statistical clustering approach. In a selected set of data on mint (Mentha sp.), we show that 'light potentials' for linear electron flow and non-photochemical quenching (NPQ) upon rapid light increases are strongly suppressed in leaves previously exposed to low ambient photosynthetically active radiation (PAR) or low leaf temperatures, factors that can act both independently and cooperatively. Further analyses allowed us to test specific mechanisms. With decreasing leaf temperature or PAR, limitations to photosynthesis during high light fluctuations shifted from rapidly induced NPQ to photosynthetic control of electron flow at the cytochrome b6f complex. At low temperatures, high light induced lumen acidification, but did not induce NPQ, leading to accumulation of reduced electron transfer intermediates, probably inducing photodamage, revealing a potential target for improving the efficiency and robustness of photosynthesis. We discuss the implications of the approach for open science efforts to understand and improve crop productivity.

Cytoprotective Effects of Water Soluble Dihydropyrimidinthione Derivative Against UV-B Induced Human Corneal Epithelial Cell Photodamage

Excessive UV-B exposure is well known to be a risk factor for corneal phototoxicity including direct DNA damage and disturbances in the antioxidant balance. Here, we showed a successful synthesis of a water-soluble and biocompatible small molecule DHPM 1 with dihydropyrimidinthione skeleton, which could effectively protect human corneal epithelial (HCE-2) cells from UV-B damage. In separate experiments, DHPM 1 absorbed UV-B rays and exhibited scavenging activity against intracellular ROS induced by UV-B radiation, thereby reducing the levels of DNA fragmentation. Additionally, UV-B exposure increased the expression of cleaved caspase-3, as well as the ratio of Bax/Bcl-2 at protein levels, while pretreatment with DHPM 1 significantly reversed these changes. To the best of our knowledge, this is the first report of a study based on dihydropyrimidinthione derivatives to develop a promising eye drops, which may well find extensive applications in UV-B caused corneal damage.

Akt activation-dependent protective effect of wild ginseng adventitious root protein against UVA-induced NIH-3T3 cell damage

Prolonged skin exposure to ultraviolet radiation can lead to development of several acute and chronic diseases, with UVA exposure considered a primary cause of dermal photodamage. We prepared a wild ginseng adventitious root extract (ARE) that could alleviate UVA irradiation-induced NIH-3T3 cell viability decline. After employing a series of purification methods to isolate main active components of ARE, adventitious root protein mixture (ARP) was identified then tested for protective effects against UVA irradiation-induced NIH-3T3 cell damage. The results showed that ARP treatment significantly reduced UVA-induced cell viability decline and confirmed that the active constituent of ARP was the protein, since proteolytic hydrolysis and heat treatment each eliminated ARP protective activity. Moreover, ARP treatment markedly inhibited UVA-induced apoptosis, cell cycle arrest and DNA fragmentation, while also significantly reversing UVA effects (elevated Bax levels, reduced Bcl-2 expression) by reducing Bax levels and increasing Bcl-2 expression. Mechanistically, ARP promoted Akt phosphorylation regardless of UVA exposure, thus confirming ARP resistance to inactivation by UVA light. Notably, in the presence of Akt inhibitor SC0227, ARP could no longer counteract UVA-induced cell viability decline and DNA fragmentation. Additionally, our results demonstrated that ARP treatment protected UVA-irradiated NIH-3T3 cells by preventing UVA-induced reduction of collagen-I expression. Taken together, these results suggest that ARP treatment of NIH-3T3 cells effectively mitigated UVA-induced cell viability decline by activating intracellular Akt to reduce UVA-induced DNA damage, leading to reduced rates of apoptosis and cell cycle arrest after UVA exposure and restoring collagen expression to normal levels.

Clinical and histologic evaluation of a fractional radiofrequency treatment of wrinkles and skin texture with novel 1-mm long ultra-thin electrode pins

Background

Fractional radiofrequency (RF) microneedling technologies have shown effectiveness in treating skin laxity and wrinkles. We report the first experience using a novel device with 1‐mm long ultrathin electrodes that utilizes a smooth RF‐assisted ablation mode.

Objective

To evaluate the safety and effectiveness of treatment with a fractional RF device using 1.0‐mm long × 0.15‐mm diameter ultrathin electrode tips for improvement of facial skin texture and wrinkles.

Methods and Materials

This was a prospective, open‐label, intraindividual‐controlled trial. Nine participants (mean age: 47.6, Fitzpatrick skin type II–IV, Fitzpatrick Elastosis Wrinkle Scale [FEWS] score: 3–6) underwent six treatment sessions with a fractional RF technology utilizing an array of 6 × 6 1‐mm long ultrathin electrodes. Treatment effectiveness was assessed by FEWS and the Global Aesthetic Improvement Scale (GAIS). Safety and tolerance were evaluated.

Results

Three months after the sixth treatment session, blinded, investigator‐assessed FEWS decreased from baseline 4.33 ± 0.67–3.33 ± 0.67 (p < 0.005); 88.9% of participants showed overall skin improvement using the physician‐assessed GAIS, and all of the participants reported improvement in skin texture and wrinkles. Treatment was well tolerated, with no adverse events and no downtime. Histological analysis in a porcine model showed a fractional pattern of epidermal ablation and dermal coagulation with intervening zones of normal healthy tissue. These changes were followed by progressive epithelialization over a period of 13 days.

Conclusion

The fractional RF technology with the novel 1.0 long × 0.15 mm ultrathin electrodes tips was effective in improving skin texture and wrinkles without impacting the participants' daily activities.

Retrospective study on the safety and tolerability of clinical treatments with a novel Thermomechanical Ablation device on 150 patients

INTRODUCTION

There are currently not many publications on the safety of thermomechanical ablation (TMA) devices, and those that are published only have small numbers of subjects. This treatment is gaining popularity in Europe and Asia, and thus there is a need to look at the safety of this treatment.

OBJECTIVE

The purpose of this retrospective study was to evaluate the safety of the clinical use of the novel TMA system (Tixel, Novoxel, Israel) for facial rejuvenation and treatment of acne scars.

METHODS

We did a retrospective review of our first 150 patients who were treated with the TMA device.

RESULTS

One hundred and fifty consecutive patients aged 20 years to 82 years with Fitzpatrick skin types I to V treated with the TMA device were included in this study. The total number of treatment sessions was 327 (average 2.18 treatment per patient). The total number of pulses delivered to these patients was 1 48 856 (average 455 pulses per session). The indications for the treatment were photodamaged skin (n=145) and acne scarring (n=5). All patients were able to use makeup immediately after the treatment at lower settings, thus needing no real recovery time. Patients treated at higher settings were able to use makeup after 2 days. There were four reported complications: post-inflammatory hyperpigmentation (n=2), impetigo (n=1), and dermatitis (n=1).

CONCLUSIONS

Using the TMA device in the treatment of photodamage and acne scarring is safe in skin types I to V and has a low incidence of temporary side effects with no permanent side effects.

Evaluation of subclinical chronic sun damage in the skin via the detection of long-lasting ultraweak photon emission

BACKGROUND

It is well known that solar radiation accelerates skin photoaging. To evaluate subclinical photodamage in the skin especially from the early phase of ultraviolet (UV)-induced damage, we have focused on ultraweak photon emission (UPE), also called biophotons. Our previous study reported that the amount of long-lasting UPE induced by UV, predominantly from lipid peroxidation, is a valuable indicator to assess cutaneous photodamage even at a suberythemal dose, although it was only applied to evaluate acute UV damage. The aim of this study was to further investigate whether long-lasting UPE could also be a useful marker to assess subclinical chronic sun damage in the course of skin photoaging.

MATERIALS AND METHODS

Forty-three Japanese females in their 20s were recruited and were divided into two groups according to their history of sun exposure based on a questionnaire (high- and low-sun-exposure groups). Several skin properties on the cheek and outer forearm were measured in addition to UV-induced UPE.

RESULTS

Among the skin properties measured, water content, average skin roughness, and the lateral packing of lipids in the stratum corneum were significantly deteriorated in the high-sun-exposure group as were changes in some skin photoaging scores such as pigmented spots and wrinkles. In addition, those skin properties were correlated with the UPE signals, suggesting the possible impact of oxidative stress on chronic skin damage.

CONCLUSION

Subtle oxidative stress detected by long-lasting UPE may contribute to subclinical cutaneous damage at the beginning phase of chronic sun exposure, which potentially enhances skin photoaging over a lifetime.

Repurposing of glycine transport inhibitors for the treatment of erythropoietic protoporphyria

Erythropoietic protoporphyria (EPP) is a rare disease in which patients experience severe light sensitivity. It is caused by a deficiency of ferrochelatase (FECH), the last enzyme in heme biosynthesis (HBS). The lack of FECH causes accumulation of its photoreactive substrate protoporphyrin IX (PPIX) in patients' erythrocytes. Here, we explored an approach for the treatment of EPP by decreasing PPIX synthesis using small-molecule inhibitors directed to factors in the HBS pathway. We generated a FECH-knockout clone from K562 erythroleukemia cells, which accumulates PPIX and undergoes oxidative stress upon light exposure. We used these matched cell lines to screen a set of publicly available inhibitors of factors in the HBS pathway. Inhibitors of the glycine transporters GlyT1 and GlyT2 lowered levels of PPIX and markers of oxidative stress selectively in K562^11B4 cells, and in primary erythroid cultures from an EPP patient. Our findings open the door to investigation of glycine transport inhibitors for HBS disorders.

Chlorophagy does not require PLANT U-BOX4-mediated ubiquitination

Chloroplasts and mitochondria serve as intracellular energy production sites that are powered by the electron transport chain in their membranes. These organelles constantly accumulate damage, as their energetic reactions generate reactive oxygen species. To prevent the accumulation of damaged organelles and perturbation of cellular homeostasis, eukaryotic cells must remove damaged mitochondria and chloroplasts. Autophagy is the main route by which organelles are degraded. A type of mitochondrion-targeted autophagy known as mitophagy removes damaged mitochondria in mammalian cells; dysfunctional mitochondria that lose their membrane potential are marked by protein ubiquitination, becoming targets of selective mitophagy. Studies of the quality control system for chloroplasts in plants revealed the involvement of both autophagy and ubiquitination in the degradation of damaged chloroplasts. We recently assessed the relationship between chloroplast-associated ubiquitination mediated by PLANT U-BOX4 (PUB4) and chloroplast-targeted autophagy (chlorophagy) in the turnover of oxidatively damaged chloroplasts. Multiple assays using an Arabidopsis thaliana mutant revealed that PUB4-associated ubiquitination is dispensable for the induction of chlorophagy. Here, we describe the parallel functions of PUB4 and chlorophagy in chloroplast turnover and plant growth.

New approaches to skin photodamage histology-Differentiating 'good' versus 'bad' Elastin

Background

Photodamage creates changes within the skin layers known as solar elastosis. This presents as fragmentation of collagen and elastin fibers, decreases in the extracellular matrix (ECM) ground substance, as well as hyaluronic acid decrease in the thinning epidermis. Traditional immunohistochemistry (IHC) staining has failed to differentiate degenerated elastin from new elastin fibers generated with various topical strategies.

Aims

A combination of stains that can offer a regenerative narrative distinguishing newly formed collagen and elastin from that of degenerated protein, thus distinguishing “good” vs “bad” elastin.

Methods

A series of stains were explored based on their ability to identify early regenerative changes within epidermal, dermal, and ECM areas to examine consistency of outcomes and reliability.

Results

A combination of Movat, fibrillin, elafin, and versican for elastogenesis and reversal of solar elastosis. CD44 for HA status (mainly epidermal) and Herovici stain for identifying early collagenesis in the ECM provides a comprehensive range of stains for identifying new elastin and collagen

Conclusion

This suggested stain combination appears to offer an ideal collection of stains for identifying regenerative events within the skin layers.

Outcomes and adverse effects of ablative vs nonablative lasers for skin resurfacing: A systematic review of 1093 patients

It is generally believed that ablative laser therapies result in prolonged healing and greater adverse events when compared with nonablative lasers for skin resurfacing. To evaluate the efficacy of ablative laser use for skin resurfacing and adverse events as a consequence of treatment in comparison to other modalities, a PRISMA-compliant systematic review (Systematic Review Registration Number: 204016) of twelve electronic databases was conducted for the terms "ablative laser" and "skin resurfacing" from March 2002 until July 2020. Studies included meta-analyses, randomized control trials, cohort studies, and case reports to facilitate evaluation of the data. All articles were evaluated for bias. The search strategy produced 34 studies. Of 1093 patients included in the studies of interest, adverse events were reported in a total of 106 patients (9.7%). Higher rates of adverse events were described in nonablative therapies (12.2% ± 2.19%, 31 events) when compared with ablative therapy (8.28% ± 2.46%, 81 events). 147 patients (13.4%) reported no side effects, 68 (6.22%) reported expected, transient self-resolving events, and five (0.046%) presented with hypertrophic scarring. Excluding transient events, ablative lasers had fewer complications overall when compared with nonablative lasers (2.56% ± 2.19% vs 7.48% ± 3.29%). This systematic review suggests ablative laser use for skin resurfacing is a safe and effective modality to treat a range of pathologies from photodamage and acne scars to hidradenitis suppurativa and posttraumatic scarring from basal cell carcinoma excision. Further studies are needed, but these results suggest that ablative lasers are a superior, safe, and effective modality to treat damaged skin.

On a Beam of Light: Photoprotective Activities of the Marine Carotenoids Astaxanthin and Fucoxanthin in Suppression of Inflammation and Cancer

Every day, we come into contact with ultraviolet radiation (UVR). If under medical supervision, small amounts of UVR could be beneficial, the detrimental and hazardous effects of UVR exposure dictate an unbalance towards the risks on the risk-benefit ratio. Acute and chronic effects of ultraviolet-A and ultraviolet-B involve mainly the skin, the immune system, and the eyes. Photodamage is an umbrella term that includes general phototoxicity, photoaging, and cancer caused by UVR. All these phenomena are mediated by direct or indirect oxidative stress and inflammation and are strictly connected one to the other. Astaxanthin (ASX) and fucoxanthin (FX) are peculiar marine carotenoids characterized by outstanding antioxidant properties. In particular, ASX showed exceptional efficacy in counteracting all categories of photodamages, in vitro and in vivo, thanks to both antioxidant potential and activation of alternative pathways. Less evidence has been produced about FX, but it still represents an interesting promise to prevent the detrimental effect of UVR. Altogether, these results highlight the importance of digging into the marine ecosystem to look for new compounds that could be beneficial for human health and confirm that the marine environment is as much as full of active compounds as the terrestrial one, it just needs to be more explored.