Photodamaged Skin Research Articles

The Glycolysis-derived α-Dicarbonyl Metabolite Methylglyoxal is a UVA-photosensitizer Causing the Photooxidative Elimination of HaCaT Keratinocytes with Induction of Oxidative and Proteotoxic Stress Response Gene Expression†.

Cellular oxidative stress contributes to solar ultraviolet (UV) radiation-induced skin photoaging and photocarcinogenesis. Light-driven electron and energy transfer reactions involving non-DNA chromophores are a major source of reactive oxygen species (ROS) in skin, and the molecular identity of numerous endogenous chromophores acting as UV-photosensitizers has been explored. Methylglyoxal (MG), a glycolytic byproduct bearing a UV-active α-dicarbonyl-chromophore, is generated under metabolic conditions of increased glycolytic flux, associated with posttranslational protein adduction in human tissue. Here, we undertook a photophysical and photochemical characterization of MG substantiating its fluorescence properties (Stokes shift), phosphorescence lifetime, and quantum yield of singlet oxygen (1 O2 ) formation. Strikingly, upon UV-excitation (290 nm), a clear emission (around 490 nm) was observed (phosphorescence-lifetime: 224.2 milliseconds). At micromolar concentrations, MG acts as a UVA-photosensitizer targeting human HaCaT-keratinocytes inducing photooxidative stress and caspase-dependent cell death substantiated by zVADfmk-rescue and Alexa-488 caspase-3 flow cytometry. Transcriptomic analysis indicated that MG (photoexcited by noncytotoxic doses of UVA) elicits expression changes not observable upon isolated MG- or UVA-treatment, with upregulation of the proteotoxic (CRYAB, HSPA6) and oxidative (HMOX1) stress response. Given the metabolic origin of MG and its role in human pathology, future investigations should address the potential involvement of MG-photosensitizer activity in human skin photodamage.

Protective Effect of Composite Hydrogel Based on Hydroxypropyl Trimethylammonium Chloride Chitosan on Skin Photodamage

Long-term or excessive exposure to UV light can lead to sunburn, erythema, melanin deposition, inflammation, and even skin cancer. This study used composite hydrogels with N-2-hydroxypropyl trimethylammonium chloride chitosan (N-2-HACC) and hyaluronic acid (HA) as carriers. In addition, ellagic acid (EA) and proanthocyanidins (PC) as functionalized materials were prepared. The infrared results show that the N-2-HACC/HA/EA/PC hydrogel is formed by N-2-HACC connecting with HA by electrostatic interaction, and HA forms hydrogen bonds between EA and PC. The in vitro antioxidant results show that EA and PC have different clearance efficiency of DPPH and superoxide anion radicals at different pH values. Thus, they have complementary effects on antioxidant properties. The cumulative release results demonstrate that the hydrogels had an excellent slow-release rate at different pHs. The animal experiments reveal that N-2-HACC/HA/EA/PC could restore the consumption of antioxidant enzymes induced by UVB irradiation and inhibit matrix metalloproteinase 1. N-2-HACC/HA/EA/PC can inhibit UVB-induced histological damage, such as epidermal thickening, collagen fiber, and elastic fiber destruction. N-2-HACC/HA/EA/PC has a significant photoprotective effect by protecting the activities of superoxide dismutase, catalase, and glutathione peroxidase and inhibiting the activity of inflammatory factors. N-2-HACC/HA/EA/PC composite hydrogel system shows comprehensive performance. Its ability to scavenge free radicals may act as an antioxidant to protect mice from skin cancer.

Formulation and characterization of Anacyclus Pyrethrum Emulgels and its in vitro and in vivo evaluation as cosmeceutical product.

Plants containing high phenolic and flavonoids contents used widely as antioxidant agent by reducing skin photo damaging effects and play important role in skin rejuvenating. This study was performed to explore the cosmetic effects of Anacyclus Pyrethrum extract and to develop stable oil in water (O/W) emulsion base gel loaded with Anacyclus Pyrethrum 10% extract. To explore and quantify phenols and flavonoids present in Anacyclus Pyrethrum extract and determine its cosmetic effects on human skin. Emulgel formulation were developed by mixing o/w emulsion with carbopol gelling agent loaded with Anacyclus Pyrethrum (AP) extract and base gel without AP extract. In vitro study was done for the evaluation of color change, liquefaction, hardness, and pH change at different storage condition for the duration of 12 weeks. For in vivo study, emulgel applied on 13 healthy human volunteer's cheeks to evaluate its cosmetics effects and compared with placebo (base). Facial parameters including skin melanin, redness, sebum, moisture content, and skin elasticity were determined by using mexameter, sebumeter, corneometer, elastometer for the study duration of 12 weeks. Total phenolic content in Anacyclus Pyrethrum extract was 80.04 ± 0.0043 mg GAE/g, and flavonoids were 54.64 ± 0.0076 mg QE/g. Anacyclus Pyrethrum extract found significantly effective in reducing skin photo-damage effects (p ≤ 0.05) as compared base gel. Anacyclus Pyrethrum extract being rich source of flavonoid and phenolic content, acts as strong antioxidant to protect skin against photo-damaging effect and improve skin conditions.

Employing hyaluronic acid-based mesotherapy for facial rejuvenation.

Mesotherapy is a method of treatment in which biocompatible substances are injected in small aliquots into different levels of skin. This technique can be used for facial rejuvenation. To comprehensively evaluate efficacy of different hyaluronic acid (HA) materials for skin rejuvenation, and discuss longevity of these products, potential adverse effects, and different injection techniques. We searched Pubmed, Scopus, Web of science, Google Scholar, Embase, Cochrane Library, and Science direct until April of 2022. Thirty-four articles were selected including 23 articles about non-cross-linked HA and 11 articles about cross-linked HA. Eleven and five different non-cross-linked HA and cross-linked HA materials were utilized, respectively. Treatment sessions for non-cross-linked HA were between 1 and 6 at weekly-to-bimonthly interval, and for cross-linked HA were 1-3 at 4-36 weeks apart. In most of the studies, serial micropuncture technique with 23-32 gauge needles was used for injection. Other injection techniques were Nappage (picotage), depot and micro-linear. Mesotherapy with HA-based fillers is a favorable method for restoring youthful appearance, rejuvenation, and revitalization of skin. Proper selection and precise placement of HA in desired level of dermis is an essential key to optimize improvement and minimize side effects including skin irregularities and Tyndall effect. Adjuvant therapy with additional rejuvenation procedures to enhance esthetic results is required especially in elderly individuals with severe photodamaged skin. Moreover, preservation of esthetic results requires maintenance therapy every few months.

Multifaceted amelioration of cutaneous photoageing by (0.3%) retinol.

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. 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. 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. 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). 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.

34481 A dual regimen skincare treatment for hyperpigmented and photodamaged facial skin

Background: Broad-spectrum mineral sunscreens have assisted in correction of pigmentary disorders. A vitamin C moisturizer (VCM) containing 30% tetrahexyldecyl (THD) ascorbate clinically demonstrated improvement in patients with mild to moderate wrinkles and hyperpigmentation in a standalone study. A dual regimen treatment containing a 100% mineral TMS and a VCM, may offer further benefits in patients concerned with their hyperpigmented and photodamaged facial skin. Study design: MatTek EpiDerm tissues topically treated with 100% mineral TMS, exposed to UVB (300 mJ/cm2) 24 hours posttreatment, and incubated for an additional 24 hours, were analyzed by ELISA for CPD formation, 8-OHdG content, and H2A.X phosphorylation (n = 3). In a multicenter, open-label study, 36 female subjects (35-60 years) with moderate to severe facial hyperpigmentation and moderate global face photodamage were recruited to assess the efficacy and tolerability of a skincare regimen containing VCM and 100% mineral TMS over 12 weeks. Clinical grading using a modified Griffith 10-point scale for hyperpigmentation, overall photodamage, and skin tone evenness were performed at baseline, weeks 4, 8, and 12. Results: The 100% mineral TMS repaired UVB induced DNA damage, including CPD formation by 85% (P < .05). When paired together, the VCM and 100% mineral TMS improved hyperpigmentation and photodamaged facial skin in patients across three clinical sites compared with baseline (P < .05). Conclusion: In vitro results coupled with in vivo results strongly suggest that the dual regimen containing 100% mineral TMS paired with the VCM was strongly effective and tolerable in improving hyperpigmented and photodamaged skin.

35406 Characterization of photodamaged skin using 3D line-field optical coherence tomography and histopathologic correlation

Noninvasive imaging techniques morphologically characterize photoaging and generate qualitative analysis in photodamaged skin. Optical coherence tomography (OCT) allows a deep laser penetration in the surface, reaching a good quality image of dermis visualization. A new 3-dimensional technology, 3D line field confocal OCT (LC-OCT) has been introduced, allowing a vertical and horizontal reconstruction of the complete skin with cellular resolution. The objective of this study was to observe in an in vivo 3-dimensional mode (3D LC-OCT) the morphologic and cytologic changes of photodamaged skin, to better understand the changes of the different skin layers induced by chronic sun exposure and responsible for chronic sun damage. 9 phototype II-III subjects were included. Dermoscopy and LC-OCT were performed on 2 zones: the sun-damaged area on the dorsal forearm and the non-sun-damaged area on the ventral side of the same forearm. Skin biopsies were obtained from both areas. All metrics were compared as paired data. LC OCT analysis showed increased epidermal thickness (mean: 5.39 μm, P = .0078) and higher number of keratinocytes (mean = 0.997; P = .002) in exposed vs nonexposed areas. The volume of the different keratinocyte layers seemed to be larger in the exposed area. Histology comparisons also showed an increased epidermal thickness on exposed areas. Significant differences were observed for the number of keratinocyte layers that was higher in photodamaged skin. This study provides for the first time a 3D quantitative analysis of photodamaged skin. There was a good correlation with histopathologic evaluation.

34428 Clinical and biophysical assessment of the effects of daily use of a nature-based, broad-spectrum mineral sunscreen containing bakuchiol in photoaged skin

Background: Skin exposure to ultraviolet radiation causes disruption of fibroblast-extracellular matrix interactions causing loss of/damage to collagen, decreased fibroblast cell density and morphology and degeneration of the elastic fiber network. These result in clinical degenerative changes such as wrinkles, sallow complexion and loss of hydration and elasticity. We developed a photostable, broad-spectrum SPF 30 product with inorganic sunscreen actives and a natural retinol alternative, bakuchiol. Objective: To investigate the effects of a nature-based mineral broad-spectrum sunscreen to improve clinical outcomes of photodamaged skin. Methods: A single-center, open-label study was performed on 49 female subjects aged 35 to 60 years with mild to moderate signs of photodamage. Evaluations of the nature-based sunscreen product were made at baseline and at week 6 after twice daily minimum topical application on the face. The dermatologist investigator and subjects assessed efficacy and tolerability using a 5-point ordinal scale (0 = none, 4 = severe). Noninvasive measurements of skin hydration, barrier function and elasticity were conducted. Results: Investigator clinical evaluations showed significant improvements in skin laxity, fine lines, smoothness, pigmentation, and texture. Subject-rated change from baseline demonstrated similar efficacy as the investigator. Skin hydration significantly improved by 21%. A significant 32% decrease in the retraction time (ms) was measured after 6 weeks of product use, indicating improved skin elasticity. There was no disruption to skin barrier function. No tolerability related issues were observed during study duration. Conclusion: Daily photoprotection using a nature-based broad-spectrum mineral sunscreen containing bakuchiol visibly improved the signs of photodamage and the skin’s biophysical properties.

DHPW1 attenuation of UVB-induced skin photodamage in human immortalized keratinocytes.

Ultraviolet radiation (UVB) can result in photodamage to the skin and can seriously threaten health, particularly in the elderly. Oxidative stress and the inflammatory response have been shown to play a significant role in the process. In a previous study, we isolated, purified and identified a polysaccharide from the extract of Dendrobium huoshanense (DHPW1). In this study we evaluated the effect of DHPW1 on ameliorating the UVB photodamage of human immortalized keratinocytes (HaCaT). Cell proliferation and cell scratch assays were used to evaluate the viability of the HaCaT treated with DHPW1, and a fluorescent probe and Western blot analysis were used to examine the production of reactive oxygen species (ROS) and the expression of proinflammatory factors IL-1β, IL-6, and NF-κB(p65). The results show that, compared with the control group (UVB irradiation only), DHPW1 significantly improved the viability of UVB-irradiated HaCaT and enhanced the migration rate of the cell scratch after 24h. The scratch-healing rate reached 90% after 36h. DHPW1 also significantly inhibited UVB-induced oxidative stress and expression of proinflammatory factors . Compared with the control group, the production of ROS decreased by 49.11%, and the relative protein expression of IL-6 and NF-κB(p65) decreased by up to 13.30% and 31.02%, respectively. It is concluded that DHPW1 can significantly improve viability and wound closure rate of UVB-irradiated HaCaT. In addition, it can reduce the expression of IL-1 and IL-6 by inhibiting the transcription of NF-κB(p65), thereby reducing inflammation and oxidative stress in UVB-irradiated HaCaT.

A case study investigating the short-term efficacy and tolerability of a daily serum composed from a unique sunflower sprout extract.

Fatigued skin, defined as dehydrated skin with lack of visual facial firmness and dull appearance, can be attributed to intrinsic and extrinsic factors of aging. An anti-aging daily serum (AADS) containing a unique sunflower sprout extract (SSE) was formulated to target fatigued and photodamaged skin. Utilizing both preclinical and clinical testing models, the efficacy of the AADS was investigated to improve fatigued and photodamaged skin. Preclinical studies included in vitro analysis of adenosine triphosphate (ATP) production in fatigued dermal fibroblasts, inhibition of ultraviolet radiation A (UVA) induced advanced glycation end products (AGEs) in keratinocytes, and ex vivo gene expression after incubation with the SSE. An institutional review board (IRB)-approved short-term, 7-day, clinical case study was conducted on 28 female subjects, Fitzpatrick skin type I-IV, aged 30-60 years with moderate overall photodamage and skin fatigue. This was a double-blinded, randomized, controlled, single-center case study testing the AADS alone and in combination with an anti-aging facial moisturizer (AAFM). The SSE boosted intracellular ATP production in fatigued fibroblasts and reduced the formation of AGEs in keratinocytes. The SSE increased expression of genes related to epidermal keratinization and downregulated genes related to inflammation. Statistically significant improvement was found after 7 days of twice-daily use of the AADS alone and in combination with the AAFM. Products were well tolerated and perceived by subjects. Preclinical results combined with the clinical results strongly suggest that the AADS containing the SSE was tolerable and effective in targeting fatigued and photodamaged skin.

Cutaneous immune-related adverse events and photodamaged skin in patients with metastatic melanoma: could nicotinamide be useful?

Cutaneous immune-related adverse events (irAEs) occur in more than one-third of patients treated with immune checkpoint inhibitors; they are often the first clinical manifestation, although they may occur months after initiation of therapy. We noticed that our patients usually have these cutaneous AEs on photodamaged skin. In fact, out of 19 patients being treated for metastatic melanoma, 8 (42%), all of whom had significant cutaneous actinic damage, developed cutaneous irAEs earlier and in a more serious form than those without such damage. Thus, we gave a high oral dose of nicotinamide (500 mg twice daily) to the patients with metastatic melanoma who had photodamaged skin, and continued this for the entire duration of the immunotherapy. The appearance of the first signs of cutaneous irAEs was 180 days after starting therapy in nicotinamide-treated patients, compared with 65 days for patients not treated with nicotinamide.

Photosensitivity and cholestatic hepatitis: the dermatologist contribution for the diagnosis of erythropoietic protoporphyria

We report a case of erythropoietic protoporphyria (EPP) in a young male adult, who was admitted to the hospital due to abdominal pain and jaundice. Complementary exams showed elevation of liver and canalicular enzymes and choledocholithiasis. The patient also had pronounced photodamaged skin and a history of significant photosensitivity since childhood. The dermatology team, based on the clinical and histological findings, gave the diagnosis of EPP and treatment with cholestyramine was instituted.

Rejuvenation of photoaged aged mouse skin using high-intensity focused ultrasound

High-intensity focused ultrasound (HIFU) therapy has emerged as an option for skin rejuvenation. However, the application against photo-damaged skin remains obscure. This study evaluates the effect of HIFU against photoaged skin using a mouse model. A total of 60 mice were used and divided into 3 groups; group 1: natural aging control group (n=20), group 2: UVB irradiation group (n=20), and group 3: UVB irradiation followed by HIFU treatment (n=20). The evaluation was made grossly by analyzing wrinkles and histologically by performing H&E, Toluidine Blue, Masson's Trichrome, and immunohistochemistry for TGF-β and MMP3. Imaging software was used to quantify the findings. Gross findings showed HIFU treated group 3 with similar findings with the control group supporting the rejuvenation effect for photo-aged skin. Histology findings with H&E show a significant reduction in skin thickness after HIFU treatment (60.115 units (group 2) vs. 40.853 units (group 3), p<0.05). Toluidine Blue and Masson's Trichrome showed improved collagen array and significantly increased distribution for group 3 over group 2 (272,879.88 units (group 2) vs. 533,805.78 units (group 3), p<0.05). Immunohistochemistry for TGF-β showed a significantly higher value for group 3 (2.45450 units) over group 2 (0.58880 units) and MMP3 with a significantly lower value for group 3 (99,180 units) over group 2 (559,830 units) (p<0.05). The treatment of HIFU supports the rejuvenation effect for photoaged skin. Findings show that HIFU provides benefits of collagen formation and rearrangement by enhancing TGF-β and inhibiting MMP3 activity. This study is the first animal study to show the direct effect of HIFU on photo-aged skin further supporting the use of HIFU in aging skin aiming to reverse the morphological effects of aging.

A new peptide originated from amphibian skin alleviates the ultravioletB-induced skinphotodamage.

Although amphibian-derived bioactive peptides have attracted increasing attention for their potential use in the treatment of photodamage, research is still in its infancy. In this study, we obtained a new antioxidant peptide, named OA-GI13 (GIWAPWPPRAGLC), from the skin of the odorous frog Odorrana andersonii and determined its effects on ultraviolet B (UVB)-induced skin photodamage as well as its possible molecular mechanisms. Results showed that OA-GI13 directly scavenged free radicals, maintained the viability of hydrogen peroxide-challenged keratinocytes, promoted the release of superoxide dismutase, catalase, and glutathione, and reduced the level of lactate dehydrogenase. Furthermore, topical application of OA-GI13 in mice alleviated dorsal skin erythema and edema and protected the skin against UVB irradiation by increasing antioxidant levels and decreasing peroxide, malondialdehyde, and 8-hydroxydeoxyguanosine levels. OA-GI13 also alleviated oxidative stress injury in vivo and in vitro, possibly by inhibiting p38 protein phosphorylation. Our study confirmed the anti-photodamage effects of this novel amphibian-derived peptide, thus providing a new molecule for the development of drugs and topical agents for the treatment of skin photodamage.

Efficacy and tolerability of a hyaluronic acid-based serum and a peptide-rich cream for the face and neck in subjects with photodamaged skin.

Barrier properties of the stratum corneum inhibit delivery of topical ingredients containing large molecules to desired targets in the skin. This study evaluated the efficacy and tolerability of a skincare regimen comprised of a hyaluronic acid-based serum (InF-HA) and a peptide-rich cream (InF-PEP) containing large molecular ingredients designed to improve the appearance and overall quality of skin. This 12-week study evaluated changes from baseline in skin tone, skin texture, and lines/wrinkles (6-point grading scale) of twice-daily application of a two-part skincare regimen to the face and neck in female subjects with mild to moderate photodamage. Subject satisfaction was assessed, and Adverse Events (AEs) were captured throughout. Seventeen subjects with a mean age of 52years completed the study. Improvements from baseline in the appearance of facial skin texture (79%), lines/wrinkles (50%), and skin tone (44%) occurred at week 12. Improvements in neck appearance from baseline were demonstrated in skin texture (68%), skin tone (48%), and lines/wrinkles (36%). No AEs occurred related to the use of study products. All subjects reported an overall improvement in the appearance of their skin and that their skin looked and felt smoother; 88% reported their skin looked more radiant, and 82% reported their skin looked firmer. Application of a skincare regimen comprised of an HA-based serum and a peptide-rich cream led to substantial improvements in skin texture, skin tone, and lines/wrinkles on the face and neck over 12weeks. Both products were well-tolerated with a high level of subject satisfaction.

Ultraviolet radiation-induced degradation of dermal extracellular matrix and protection by green tea catechins: a randomized controlled trial.

BackgroundLoss and remodelling of the dermal extracellular matrix (ECM) are key features of photodamaged human skin. Green tea catechins (GTCs) have been explored for their anti‐inflammatory and chemopreventive properties, but data on the impact of GTCs on ultraviolet radiation (UVR)‐induced changes to the dermal ECM are lacking.AimTo investigate the effect of an inflammatory dose of solar‐simulated UVR on human dermal ECM and potential for protection by GTCs in a double‐blind randomized controlled trial.MethodsIn total, 50 healthy white (Fitzpatrick skin type I–II) adults aged 18–65 years were randomized to a combination of GTCs 540 mg plus vitamin C 50 mg or to placebo twice daily for 12 weeks. The impact of solar‐simulated UVR at 3 × minimal erythema dose on the dermal collagen and elastic fibre networks was assessed by histology and immunohistochemistry in all participants at baseline. The impact of GTC supplementation on UVR‐induced effects was compared between the groups post‐supplementation.ResultsThe area of papillary dermis covered by collagen and elastic fibres was significantly lower (P < 0.001) in UVR‐exposed skin than in unexposed skin. Significantly lower levels of fibrillin‐rich microfibrils (P = 0.02), fibulin‐2 (P < 0.001) and fibulin‐5 (P < 0.001) were seen in UVR‐exposed than unexposed skin, while procollagen‐1 deposition was significantly higher in UVR‐exposed skin (P = 0.01). Following GTC supplementation, the UVR‐induced change in fibulin‐5 was abrogated in the active group but not the placebo group, with no difference between the two groups for other components.ConclusionsAcute UVR induced significant changes in the human dermal collagen and elastic fibre networks, whereas oral GTCs conferred specific UVR protection to fibulin‐5. Future studies could explore the impact of GTCs on the effects of repeated suberythemal UVR exposure of human skin.

Correction to ‘Landscape dynamic network biomarker analysis reveals the tipping point of transcriptome reprogramming to prevent skin photodamage’

Correction to ‘Landscape dynamic network biomarker analysis reveals the tipping point of transcriptome reprogramming to prevent skin photodamage’

In Vivo Identification of Skin Photodamage Induced by Fractional CO2 and Picosecond Nd:YAG Lasers with Optical Coherence Tomography

Fractional laser treatment is commonly used for dermatological applications, enabling effective induction of collagen regeneration and significantly reducing recovery time. However, it is challenging to observe laser-induced photodamage beneath the tissue surface in vivo, making the non-invasive evaluation of treatment outcomes difficult. For in vivo real-time study of the photodamage induced by fractional pulsed CO2 and Nd:YAG lasers commonly utilized for clinical therapy, a portable spectral-domain optical coherence tomography (SD-OCT) system was implemented for clinical studies. The photodamage caused by two lasers, including photothermal and photoacoustic effects, was investigated using OCT, together with the correlation between photodamage and exposure energy. Additionally, to investigate the change in the optical properties of tissue due to photodamage, the attenuation coefficients and damaged areas of normal skin and laser-treated skin were estimated for comparison. Finally, the recovery of the exposed skin with both lasers was also compared using OCT. The results show that OCT can be a potential solution for in vivo investigation of laser-induced tissue damage and quantitative evaluation.

Effect of Apple (Malus domestica) Stem Cells on UVB-Induced Damage Skin with Anti-Inflammatory Properties: An In Vivo Study

Objective. Apple (Malusdomesticus) stem cells have beneficial effects in preventing photodamages caused by UVB responsible for inflammation in different stages of various skin disorders. This study aimed to investigate Apple stem cells’ anti-inflammatory and repairing effects on UVB-induced rat dorsal skin damage via microscopic and macroscopic analyses. Materials and Methods. Therapeutic effects of the apple stem cells (ASCs) extract were evaluated after UVB irradiation with macroscopic and microscopic studies, including pathological analysis, inflammatory cytokines measuring, and biometric studies containing investigation of thickness, density, erythema, melanin, sebum, and moisture content of epidermis and dermis layers in rat models. After biometric studies, skin samples were taken for histopathologic and biochemical analyses. Results. ASC extract could attenuate infiltration of inflammatory cells caused by UVB and ameliorate collagen regulation of the photodamaged skin. In addition, improved skin biometrics was considerable, such as reducing thickened epidermal and dermal layers compared to other rat groups. Furthermore, moisture content enhancement of the skin showed clinical advantages in treating damages and inflammation. Furthermore, TNF-α expression was downregulated after ASC application. ASC extract could treat UVB damages and indicate anti-inflammatory effects in animal models. Conclusion. The ASCs can be an appropriate candidate for treating inflammation and damages induced by UVB in clinical studies.

Solar keratosis

Solar keratosis is a common skin condition characterised by scaly skin lesions, usually found on sun-exposed areas of the body. It is also known as actinic keratosis, senile keratosis and solar keratosis; the name originates from Latin and means ‘skin thickening due to sun'. It was first described by Dubreuilh in 1826, and for many years was known as ‘keratoma senilis’. In 1958 it was finally named actinic keratosis, by Pinkus. Solar keratotsis represents dysplastic proliferations of keratinocytes, secondary to chronic sun exposure, especially ultra-violet radiation. Solar keratosis is the most common pre-malignant skin condition; however, it is increasingly thought to represent a spectrum of disease in between photo-damaged skin and squamous cell carcinoma (SCC). A small proportion of solar keratosis progresses to become SCC, and the chances of progression increase with the increase in the number of lesions. Incidence of solar keratosis in the UK is increasing due to an ageing population, leading to increased burden on the healthcare system.