Ageing and photoageing of the skin: observations at the cellular and molecular level

Use of a fractional 1570-nm diode laser scanner for nonablative face and neck rejuvenation

BACKGROUND

The use of non-ablative fractionated lasers for skin rejuvenation has been proven to be effective in improving skin texture, and has become popular due to minimal wounding, significantly shorter recovery times and decreased adverse effects.

OBJECTIVE

To retrospectively analyze improvement in skin texture in healthy women aged over 18 years with Fitzpatrick skin type II-IV.

METHODS

Participants received 3 facial and/or neck treatments with the 1570-nm fractional scanning diode laser at one-month intervals. Three months after the last treatment session two blinded evaluators assessed skin improvement using before and after photos. Pain and patient satisfaction were recorded.

RESULTS

Sixteen women with a mean age of 45.4 ± 4.1 years (range 35-50 years) and skin type II-IV were included in the analysis. All 16 participants received facial treatments and seven (43.8%) also received neck treatments. Three months follow-up evaluation showed that the majority of participants had at least a visible change in the treated areas. Mean pain score was low and decreased with each treatment session.

CONCLUSION

Skin treatment using fractional scanning 1570-nm diode laser improves skin laxity in women with skin types II-IV. Larger studies are warranted to further clarify the efficacy and safety of this modality.

Green preparation and evaluation of the anti-psoriatic activity of vesicular elastic nanocarriers of kojic acid from Aspergillus oryzae N12: Repurposing of a dermo-cosmetic lead

Psoriasis is a skin disorder characterized by impaired epidermal differentiation that is regularly treated by systemic drugs with undesirable side effects. Based on its anti-inflammatory, antiproliferative and anti-melanoma attributes, the fungal metabolite kojic acid represents an attractive candidate for anti-psoriatic research. The present work aims to investigate an efficient topical bio-friendly vesicular system loaded with kojic acid isolated from Aspergillus oryzae as an alternative way for the management of psoriasis to avoid systemic toxicity. Kojic acid-loaded spanlastics were prepared by ethanol injection technique, employing span 60 along with brij 35 and cremophor rh40 as edge activators, with the complete in vitro characterization of the developed nanoplatform. The selected formulation displayed a spherical morphology, an optimum particle size of 234.2 ± 1.65 nm, high entrapment efficiency (87.4% ± 0.84%) and significant sustained drug release compared with the drug solution. In vivo studies highlighted the superior relief of psoriasis symptoms and the ability to maintain healthy skin with the least changes in mRNA expression of inflammatory cytokines, achieved by the developed nanoplatform compared to kojic acid solution. Moreover, the in vivo histopathological studies confirmed the safety of the topically applied spanlastics. In addition, the molecular mechanism was approached through in vitro assessment of cathepsin S and PDE-4 inhibitory activities and in silico investigation of kojic acid docking in several anti-psoriatic drug targets. Our results suggest that a topically applied vesicular system loaded with kojic acid could lead to an expansion in the dermo-cosmetic use of kojic acid as a natural bio-friendly alternative for systemic anti-psoriatic drugs.

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.

Use of a fractional 1570-nm diode laser scanner for non-ablative face and neck rejuvenation

BACKGROUND

The use of non-ablative fractionated lasers for skin rejuvenation has been proven to be effective in improving skin texture, and has become popular due to minimal wounding, significantly shorter recovery times and decreased adverse effects.

OBJECTIVE

To retrospectively analyze improvement in skin texture in healthy women aged over 18 years with Fitzpatrick skin types II-IV.

METHODS

Participants received three facial and/or neck treatments with the 1570-nm fractional scanning diode laser at 1-month intervals. Three months after the last treatment session two blinded evaluators assessed skin improvement using before and after photos. Pain and patient satisfaction were recorded.

RESULTS

Sixteen women with a mean age of 45.4 ± 4.1 years (range 35-50 years) and skin type II-IV were included in the analysis. All 16 participants received facial treatments and seven (43.8%) also received neck treatments. Three months follow-up evaluation showed that the majority of participants had a visible change in the treated areas. Mean pain score was low and decreased with each treatment session.

CONCLUSION

Skin treatment using fractional scanning 1570-nm diode laser improves skin laxity in women with skin types II-IV. Larger studies are warranted to further clarify the efficacy and safety of this modality.

Fisetin Inhibits UVA-Induced Expression of MMP-1 and MMP-3 through the NOX/ROS/MAPK Pathway in Human Dermal Fibroblasts and Human Epidermal Keratinocytes

Fisetin is a flavonoid found in plants and has been reported to be effective in various human diseases. However, the effective mechanisms of ultraviolet-A (UVA)-mediated skin damage are not yet clear. In this study, we investigated the protective mechanisms of fisetin regarding UVA-induced human dermal fibroblasts (HDFs) and human epidermal keratinocytes (HEKs) damages. Fisetin showed a cytoprotective effect against UVA irradiation and suppressed matrix metalloproteinases (MMPs), MMP-1, and MMP-3 expression. In addition, fisetin was rescued, which decreased mRNA levels of pro-inflammatory cytokines, reactive oxygen species production, and the downregulation of MAPK/AP-1 related protein and NADPH oxidase (NOX) mRNA levels. Furthermore, UVA-induced MMP-1 and MMP-3 were effectively inhibited by siRNAs to NOX 1 to 5 in HDFs and HEKs. These results indicate that fisetin suppresses UVA-induced damage through the NOX/ROS/MAPK pathway in HDFs and HEKs.

Protective effects of red orange (Citrus sinensis [L.] Osbeck [Rutaceae]) extract against UVA-B radiation-induced photoaging in Skh:HR-2 mice

BACKGROUND/OBJECTIVES

The skin is the outermost organ of the human body and plays a protective role against external environmental damages, such as sunlight and pollution, which affect anti-oxidant defenses and skin inflammation, resulting in erythema or skin reddening, immunosuppression, and epidermal DNA damage.

MATERIALS/METHODS

The present study aimed to investigate the potential protective effects of red orange complex H extract (ROC) against ultraviolet (UV)-induced skin photoaging in Skh:HR-2 mice. ROC was orally administered at doses of 20, 40, and 80 mg/kg/day for 13 weeks, along with UV irradiation of the mice for 10 weeks.

RESULTS

ROC improved UV-induced skin barrier parameters, including erythema, melanin production, transepidermal water loss, elasticity, and wrinkle formation. Notably, ROC inhibited the mRNA expression of pro-inflammatory cytokines (interleukin 6 and tumor necrosis factor α) and melanogenesis. In addition, ROC recovered the UV-induced decrease in the hyaluronic acid and collagen levels by enhancing genes expression. Furthermore, ROC significantly downregulated the protein and mRNA expression of matrix metalloproteinases responsible for collagen degradation. These protective effects of ROC against photoaging are associated with the suppression of UV-induced phosphorylation of c-Jun NH2-terminal kinase and activator protein 1 activation.

CONCLUSIONS

Altogether, our findings suggest that the oral administration of ROC exerts potential protective activities against photoaging in UV-irradiated hairless mice.

Antiphotoaging Effect of AGEs Blocker™ in UVB-Irradiated Cells and Skh:HR-1 Hairless Mice

Chronic exposure to ultraviolet (UV) radiation is a major cause of photoaging. It involves extrinsic aging, wrinkle formation, and skin dehydration, and leads to excessive production of active oxygen that adversely affects the skin. Here, we investigated the antiphotoaging effect of AGEs Blocker^TM (AB), which comprises Korean mint aerial part and fig and goji berry fruits. Compared to its individual components, AB was more potent at increasing the expression of collagen and hyaluronic acid and decreasing MMP-1 expression in UVB-irradiated Hs68 fibroblasts and HaCaT keratinocytes. In Skh:HR-1 hairless mice exposed to 60 mJ/cm² UVB for 12 weeks, oral administration of 20 or 200 mg/kg/day AB restored skin moisture by improving UVB-induced erythema, skin moisture, and transepidermal water loss, and alleviated photoaging by improving UVB-induced elasticity and wrinkles. Moreover, AB upregulated the mRNA levels of hyaluronic acid synthase and collagen-related Col1a1, Col3a1, and Col4a1 genes, increasing hyaluronic acid and collagen expression, respectively. AB inhibited UVB-induced MAPK and AP-1 (c-fos) activation, resulting in significantly downregulated expression of MMP-1 and -9, which are responsible for collagen degradation. AB also stimulated the expression and activity of antioxidative enzymes and reduced lipid peroxidation. Thus, AB is a potential preventive and therapeutic agent for photoaging.

Helwah MK, Noureldin MH, Abbas H. Dual-effects of caffeinated hyalurosomes as a nano-cosmeceutical gel counteracting UV-induced skin ageing

Caffeine (CAF) is a challenging natural bioactive compound with proven antiaging efficacy. However, being hydrophilic hampers its permeation through the skin. Our aim is to develop a novel CAF-loaded nano-cosmeceutical tool counteracting skin photoaging via improving CAF skin permeation using a bioactive nanocarrier. Caffeinated hyalurosomes are novel biocompatible antiaging nanoplatforms designed by immobilization of phospholipid vesicles with a hyaluronan polymer. Physicochemical properties of the selected hyalurosomes formulation showed nano-sized vesicles (210.10 ± 1.87 nm), with high zeta potential (-31.30 ± 1.19 mv), and high encapsulation efficiency (84.60 ± 1.05%). In vitro release results showed outstanding sustained release profile from caffeinated hyalurosomes compared to the CAF-loaded in conventional gel over 24 h. The in-vivo study revealed a photoprotective effect of caffeinated hyalurosomes, reflected from the intact and wrinkling-free skin. Results of biochemical analyses of oxidative stress, pro-inflammatory mediators, and anti-wrinkling markers further confirmed the efficacy of the prepared hyalurosomes compared to the CAF conventional gel. Finally, histopathological examination demonstrated normal histological structures of epidermal layers with minimal inflammatory cell infiltrates in the caffeinated hyalurosomes group compared to the positive control group. Conclusively, caffeinated hyalurosomes successfully achieved enhanced CAF loading and penetration into the skin besides the hydration effect of hyaluronan. Consequently, the developed delivery system presents a promising skin protection nano-platforms via the double effects of both hyaluronan and CAF, hence it guards against skin photodamage.

Novel Siprulina platensis Bilosomes for Combating UVB Induced Skin Damage

The recent interest in bioactive compounds from natural sources has led to the evolution of the skin care industry. Efforts to develop biologically active ingredients from natural sources have resulted in the emergence of enhanced skin care products. Spirulina (SPR), a nutritionally enriched cyanobacteria-type microalga, is rich in nutrients and phytochemicals. SPR possesses antioxidant, immunomodulatory, and anti-inflammatory activities. Spirulina-loaded bilosomes (SPR-BS), a novel antiaging drug delivery system, were designed for the first time by incorporation in a lecithin−bile salt-integrated system for bypassing skin delivery obstacles. The optimized BS had good entrapment efficiency, small particle size, optimal zeta potential, and sustained drug release pattern. Blank and SPR-loaded BS formulations were safe, with a primary irritancy index of <2 based on the Draize test. In vivo tests were conducted, and photoprotective antiaging effects were evaluated visually and biochemically by analyzing antioxidant, anti-inflammatory, and anti-wrinkling markers following ultraviolet (UV) B irradiation. Results of biochemical marker analysis and histopathological examination confirmed the superior antiaging effect of SPR-BS compared with SPR. Thus, SPR-loaded BS is a promising nanoplatform for SPR delivery, can be used for treating UV-induced skin damage, and offers maximum therapeutic outcomes.

The CSIESA: A Novel Score for the Assessment of Intrinsic and Extrinsic Skin Aging Based on Reflectance Confocal Microscopy Imaging

Skin aging is an intricate physiological process governed by intrinsic and extrinsic factors. Increasing life expectancy has turned skin aging into a growing concern for the general population. Clinical examination of the skin does not fully describe the skin aging process. This study aims to evaluate the healthy skin of five different age groups in order to develop an easy-to-use confocal score for quantifying signs of skin aging and test the correlation between this new score and the already described clinical score, SCINEXA (score of intrinsic and extrinsic skin aging). Thirty-five subjects split into five age groups: <35; 36−45; 46−55; 56−65, and >65 years old were enrolled. Clinical signs were quantified using the SCINEXA score, and known confocal variables of skin aging were evaluated. Three different semi-quantitative scores were calculated: epidermal disarrangement score (EDS), epidermal hyperplasia score (EHS), and dermal score (DS). The EDS showed a stable trend up to the age of 65 and a dramatic increase in older subjects. EHS was characterized by an ascending trend from younger subjects to middle-aged ones. The DS was progressive with age, with a different proportion of distinct collagen types. The confocal CSIESA (confocal score for the assessment of intrinsic and extrinsic skin aging) score correlated well with the SCINEXA score. Reflectance confocal microscopy is a powerful, non-invasive technique for microscopically quantifying aging signs.

Sphingolipids as Functional Food Components: Benefits in Skin Improvement and Disease Prevention

Sphingolipids are ubiquitous components in eukaryotic organisms and have attracted attention as physiologically functional lipids. Sphingolipids with diverse structures are present in foodstuffs as these structures depend on the biological species they are derived from, such as mammals, plants, and fungi. The physiological functions of dietary sphingolipids, especially those that improve skin barrier function, have recently been noted. In addition, the roles of dietary sphingolipids in the prevention of diseases, including cancer and metabolic syndrome, have been studied. However, the mechanisms underlying the health-improving effects of dietary sphingolipids, especially their metabolic fates, have not been elucidated. Here, we review dietary sphingolipids, including their chemical structures and contents in foodstuff; digestion, intestinal absorption, and metabolism; and nutraceutical functions, based on the available evidence and hypotheses. Further research is warranted to clearly define how dietary sphingolipids can influence human health.

Protective roles of mesenchymal stem cells on skin photoaging: A narrative review

Skin is a natural barrier of human body and a visual indicator of aging process. Exposure to ultraviolet (UV) radiation in the sunlight may injure the skin tissues and cause local damage. Besides, it is reported that repetitive or long-term exposure to UV radiation may reduce the collagen production, change the normal skin structure and cause premature skin aging. This is termed "photoaging". The classical symptoms of photoaging include increased roughness, wrinkle formation, mottled pigmentation or even precancerous changes. Mesenchymal stem cells (MSCs) are a kind of cells with the ability of self-renewal and multidirectional differentiation into many types of cells, like adipocytes, osteoblasts and chondrocytes. Researchers have explored diverse pharmacological actions of MSCs because of their migratory activity, paracrine actions and immunoregulation effects. In recent years, the huge potential of MSCs in preventing skin from photoaging has gained wide attention. MSCs exert their beneficial effects on skin photoaging via antioxidant effect, anti-apoptotic/anti-inflammatory effect, reduction of matrix metalloproteinases (MMPs) and activation of dermal fibroblasts proliferation. MSCs and MSC related products have demonstrated huge potential in the treatment of skin photoaging. This narrative review concisely sums up the recent research developments on the roles of MSCs in protection against photoaging and highlights the enormous potential of MSCs in skin photoaging treatment.

An analysis of skin thickness in the Dezhou donkey population and identification of candidate genes by RNA-seq

The aim of the present study was to analyze the main factors that have a significant impact on skin thickness, and to further identify the genes and signaling pathways regulating skin growth by RNA-seq in Dezhou donkeys. Skin samples from different body regions of 15 slaughtered donkeys were obtained to study variations in skin thickness over the bodies. Skin thickness data for another 514 donkeys was obtained by minimally invasive skin sampling from the back, and measurements of the donkeys' body size traits and pedigree data were also collected. These data were used to analyze changes in skin thickness and estimate genetic parameters. In addition, transcriptomic analysis was conducted on the skin tissues of individuals from two groups with significant differences in skin thickness. Our results showed that skin thickness over the bodies ranged from 1.08 to 4.36 mm. The skin from the back was the thickest and had the highest correlation with that of other regions of the body. The skin thickness decreased from the back to the side of the ventral abdomen, and the skin thickness on the limbs increased from the proximal end to the distal end. The results also showed that the skin from the same body regions of jacks was thicker than that of jennies in the same age group. The skin thickness of jennies increased from birth to the age of 2 and then clearly decreased after 2 years of age. The estimated heritability of skin thickness was 0.15, and the genetic correlations between skin thickness and body size traits were negligible. Transcriptome analysis showed that the thick-skin group had 65 up-regulated genes and 38 down-regulated genes compared with the thin-skin group. The differentially expressed genes were highly enriched in epidermal development and cell adhesion molecule signaling pathways. We identified the candidate genes responsible for variations in skin thickness in the Dezhou donkey, including KRT10, KRT1, CLDN9, MHCII and MMP28. These results contribute to a better understanding of the growth and development of donkey skin, reveal the molecular mechanism responsible for donkey skin thickness and suggest directions for genetic selection in the Dezhou donkey population.

Systematic Review and Meta-Analysis on the Effects of Astaxanthin on Human Skin Ageing

Context: Astaxanthin (ASX), a xanthophyll carotenoid derived from microalgae Haematococcus pluvialis, mitigating skin photoaging and age-related skin diseases by its antioxidant and anti-inflammatory effects in animal studies. Objective: The aim was to systematically evaluate if ASX applications have anti-ageing effects in humans. Methods: A comprehensive search of PubMed, Scopus and Web of Science found a total of eleven studies. Nine randomised, controlled human studies assessed oral ASX effects and two open-label, prospective studies evaluated topical, oral-topical ASX effects on skin ageing. GetData Graph Digitizer was used to extract mean values and standard deviations of baseline and endpoint, and Cochrane Collaboration’s tool assessed RoB for all included studies. Review Manager 5.4 was used to conduct meta-analysis of RCTs; the results were reported as effect size ± 95% confidence interval. Results: Oral ASX supplementation significantly restored moisture content (SMD = 0.53; 95% CI = 0.05, 1.01; I² = 52%; p = 0.03) and improved elasticity (SMD = 0.77; 95% CI = 0.19, 1.35; I² = 75%; p = 0.009) but did not significantly decrease wrinkle depth (SMD = −0.26; 95% CI = −0.58, 0.06; I² = 0%; p = 0.11) compared to placebo. Open-label, prospective studies suggested slightly protective effects of topical and oral-topical ASX applications on skin ageing. Conclusions: Ingestion and/or topical usages of ASX may be effective in reducing skin ageing and have promising cosmetical potential, as it improves moisture content and elasticity and reduces wrinkles.

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.

Protective Effects of Astaxanthin Supplementation against Ultraviolet-Induced Photoaging in Hairless Mice

Ultraviolet (UV) light induces skin photoaging, which is characterized by thickening, wrinkling, pigmentation, and dryness. Astaxanthin (AST), a ketocarotenoid isolated from Haematococcus pluvialis, has been extensively studied owing to its possible effects on skin health as well as UV protection. In addition, AST attenuates the increased generation of reactive oxygen species (ROS) and capillary regression of the skeletal muscle. In this study, we investigated whether AST could protect against UV-induced photoaging and reduce capillary regression in the skin of HR-1 hairless mice. UV light induces wrinkle formation, epidermal thickening, and capillary regression in the dermis of HR-1 hairless mice. The administration of AST reduced the UV-induced wrinkle formation and skin thickening, and increased collagen fibers in the skin. AST supplementation also inhibited the generation of ROS, decreased wrinkle formation, reduced epidermal thickening, and increased the density of capillaries in the skin. We also found an inverse correlation between wrinkle formation and the density of capillaries. An association between photoaging and capillary regression in the skin was also observed. These results suggest that AST can protect against photoaging caused by UV irradiation and the inhibitory effects of AST on photoaging may be associated with the reduction of capillary regression in the skin.

Xanthophyll: Health benefits and therapeutic insights

Xanthophylls constitute a major part of carotenoids in nature. They are an oxidized version of carotenoid. Xanthophyll has widely drawn scientists' attentions in terms of its functionality, bioavailability and diversity. An assortment of xanthophyll varieties includes lutein, zeaxanthin, β-cryptoxanthin, capsanthin, astaxanthin, and fucoxanthin. Chemically, lutein and zeaxanthin are dipolar carotenoids with hydroxyl groups at both ends of their molecules that bestow hydrophilic properties to them. Hydrophilic affinity in lutein and zeaxanthin makes better bioavailability in reaction with singlet oxygen in water phase, whereas non-polar carotenoids have shown to have less efficiency in scavenging free radicals. Xanthophylls have been studied for their effects in a wide variety of diseases including neurologic, ophthalmologic, oral, allergic and immune diseases. This review highlights pharmaco-pharmaceutical applications of xanthophylls as well asits drug interactions with beta-carotene. Different types of xanthophylls have been shown to have neuroprotective effects. Fucoxanthin demonstrated potent antiplasmodial activity. Lutein and zeaxanthin prevent the progression of age related macular degeneration. They have also demonstrated promising effects on uveitis, retinitis pigmentosa, scleritis, cataracts, glaucoma, retinal ischemia and choroideremia. Astaxanthin showed to have skin protecting effects against ultraviolet light injury. Astaxanthin have anti-allergic activity against the contact dermatitis especially to treat the patients having adverse reactions induced by steroids. Astaxanthin has been reported to exert beneficial effects in preventing oral lichen planus and early stage cancers. β-cryptoxanthin has been considered a good candidate for prevention of bone loss via osteoblastic bone formation and inhibiting osteoclastic bone resorption. There is also some concern that higher dose of xanthophylls may be linked to increased risk of skin cancer and gastric adenocarcinoma. However this increased risk was not statistically significant when adjusted for confounding factors. Further researches including clinical studies are needed to better evaluate the efficacy and safety of xanthophylls in prevention and treatment of different diseases.

Scarless wound healing: From development to senescence

An essential element of tissue homeostasis is the response to injuries, cutaneous wound healing being the most studied example. In the adults, wound healing aims at quickly restoring the barrier function of the skin, leading however to scar, a dysfunctional fibrotic tissue. On the other hand, in fetuses a scarless tissue regeneration takes place. During ageing, the wound healing capacity declines; however, in the absence of comorbidities a higher quality in tissue repair is observed. Senescent cells have been found to accumulate in chronic unhealed wounds, but more recent reports indicate that their transient presence may be beneficial for tissue repair. In this review data on skin wound healing and scarring are presented, covering the whole spectrum from early embryonic development to adulthood, and furthermore until ageing of the organism.

Hawthorn Polyphenol Extract Inhibits UVB-Induced Skin Photoaging by Regulating MMP Expression and Type I Procollagen Production in Mice

Ultraviolet (UV) B radiation can cause skin aging by increasing matrix metalloproteinase (MMP) production and collagen degradation, leading to the formation of wrinkles. This study investigated whether hawthorn polyphenol extract (HPE) protects against UVB-induced skin photoaging using HaCaT human keratinocytes, normal human dermal fibroblasts (HDFs), and mice. Analysis of the phenol composition of HPE by high-performance liquid chromatography-mass spectrometry showed that chlorogenic acid (13.5%), procyanidin B2 (19.2%), and epicatechin (18.8%) collectively accounted for 51.4% of total phenol content and represent the active ingredients of hawthorn fruit. A cell viability assay revealed that HPE treatment promoted cell proliferation in HaCaT cells and HDFs. On the other hand, MMP-1 and type I procollagen production was decreased and increased, respectively, in UVB-exposed cells treated with HPE as compared with those without treatment, as determined by enzyme-linked immunosorbent assay. Hematoxylin and eosin and Weigert staining of dermal tissue specimens from mice demonstrated that HPE also reversed UVB-induced epidermal thickening and dermal damage. The increase in production of reactive oxygen species and decrease in antioxidant enzyme activity as well as the increase in nuclear factor-κB activation and mitogen-activated protein kinase phosphorylation induced by UVB irradiation were reversed by HPE (100 or 300 mg/kg body weight), which also suppressed MMP expression and stimulated the production of type I procollagen in the dorsal skin of UVB-irradiated mice. These results suggest that HPE is a natural product that can prevent UVB radiation-induced skin photoaging.

Dermal anti-oxidant, anti-inflammatory and anti-aging effects of Compritol ATO-based Resveratrol colloidal carriers prepared using mixed surfactants

In this study, Compritol ATO-based Resveratrol colloidal carriers (CCCs) were prepared and subjected to characterization and evaluation. In most formulae, the use of a binary-mixture of surfactants improved the physicochemical properties. CCC6 (containing P407/P188 as bi-surfactants) attained the highest drug loading, release efficiency during 24 h and occlusive effect for 48 h; in addition, it showed a uniform particle size distribution within the desired range. In-vivo studies were done based on the analysis of anti-oxidant markers [catalase (CAT), reduced glutathione (GSH) and superoxide dismutase (SOD)], anti-inflammatory markers [interleukin 6 (IL-6), interleukin 8 (IL-8) and rat Nuclear factor-kappa B (NF-κB)] and anti-wrinkling markers [matrix metalloproteinase (MMP-1) and Granulocyte-macrophage colony-stimulating factor (GM-CSF)], after UVB-irradiation. Results were significantly different when comparing the positive control and the negative control groups (p < 0.05). Rats pre-treated with CCC6 showed a great amelioration, and the level of the biochemical markers was significantly different compared to those of the positive control group and those pre-treated with the drug suspension (p < 0.05). Also, the high skin protective effect of CCC6 was proved by visual and histopathological examination of the rats' skin. Therefore, the current study proves the beneficial effects of the designed dermal Resveratrol-loaded colloidal system.

The Ginsenoside Derivative 20(S)-Protopanaxadiol Inhibits Solar Ultraviolet Light-Induced Matrix Metalloproteinase-1 Expression

Ginsenosides are major pharmacologically active compounds present in ginseng (Panax ginseng). Among the ginsenosides, 20-O-β-D-glucopyranosyl-20(S)-protopanaxadiol (GPPD) and ginsenoside Rb1 (Rb1) have previously been reported to exhibit anti-wrinkle effects. In this study, 20(S)-protopanaxadiol (20(S)-PPD), an aglycone derivative of the Rb1 metabolite was investigated for its anti-wrinkle benefit and compared to GPPD and Rb1. The anti-wrinkle effect of 20(S)-PPD during solar UV light was investigated using a human skin equivalent model and human keratinocytes. 20(S)-PPD attenuated solar UV-induced matrix metalloproteinase (MMP)-1 expression to a greater extent than GPPD and Rb1. 20(S)-PPD treatment modulated MMP-1 mRNA expression and the transcriptional activity of activator protein (AP)-1, a major transcription factor of MMP-1. Two upstream signaling pathways for AP-1, the MEK1/2-ERK1/2-p90^RSK and MEK3/6-p38 pathways, were also suppressed. Taken together, these findings highlight the potential of 20(S)-PPD for further development as a preventative agent for sunlight-induced skin wrinkle. J. Cell. Biochem. 118: 3756-3764, 2017. © 2017 Wiley Periodicals, Inc.

Diosmin/essential oil combination for dermal photo-protection using a lipoid colloidal carrier

Solar irradiation induces skin inflammatory processes causing deleterious effects like premature ageing. In this study, the designed lipoid colloidal carrier (LCC) was loaded with Diosmin in combination with different essential oils, to be used as a topical photo-protective preparation. To investigate the ability of the essential oils to potentiate Diosmin effects, the Diosmin/essential oil-loaded LCCs (LCC2, LCC3 and LCC4) were compared to the Diosmin-loaded LCC (LCC1). The incorporated essential oils were those of Rosmarinus officinalis, Zingiber officinale or Vitis vinifera in LCC2, LCC3 and LCC4, respectively. All the LCCs had particle size (PS) values ranging from 121.1 to 144.3nm with uniform distribution and, zeta potential (Z) values around 30mV. Also, they all had high drug encapsulation efficiencies. LCC1 had the lowest anti-oxidant and in-vitro sun-blocking effect (p<0.05). In-vivo photo-protective studies showed that all the formulated LCCs had a skin protective effect when compared to the positive control (p<0.05); however LCC1 had the lowest anti-erythemal and anti-wrinkling effect. Histological studies proved the efficacy of the designed LCCs as skin anti-photoageing, with LCC1 showing the lowest anti-inflammatory and anti-wrinkling effect, while LCC2 had the highest anti-wrinkling effect. These results indicated that the suggested Diosmin/essential oil combinations improved the anti-oxidant, sun-blocking and anti-photoageing effects of Diosmin. After one year of storage, the LCCs showed satisfactory physical stability. This study presents the designed LCCs as safe and effective nano-structured dermal care products containing 'all-natural' components.

Preventive effect of dietary astaxanthin on UVA-induced skin photoaging in hairless mice

Astaxanthin, a carotenoid found mainly in seafood, has potential clinical applications due to its antioxidant activity. In this study, we evaluated the effect of dietary astaxanthin derived from Haematococcus pluvialis on skin photoaging in UVA-irradiated hairless mice by assessing various parameters of photoaging. After chronic ultraviolet A (UVA) exposure, a significant increase in transepidermal water loss (TEWL) and wrinkle formation in the dorsal skin caused by UVA was observed, and dietary astaxanthin significantly suppressed these photoaging features. We found that the mRNA expression of lympho-epithelial Kazal-type-related inhibitor, steroid sulfatase, and aquaporin 3 in the epidermis was significantly increased by UVA irradiation for 70 days, and dietary astaxanthin significantly suppressed these increases in mRNA expression to be comparable to control levels. In the dermis, the mRNA expression of matrix metalloprotease 13 was increased by UVA irradiation and significantly suppressed by dietary astaxanthin. In addition, HPLC-PDA analysis confirmed that dietary astaxanthin reached not only the dermis but also the epidermis. Our results indicate that dietary astaxanthin accumulates in the skin and appears to prevent the effects of UVA irradiation on filaggrin metabolism and desquamation in the epidermis and the extracellular matrix in the dermis.

Hesperidin Attenuates Ultraviolet B-Induced Apoptosis by Mitigating Oxidative Stress in Human Keratinocytes

Human skin cells undergo pathophysiological processes via generation of reactive oxygen species (ROS) upon excessive exposure to ultraviolet B (UVB) radiation. This study investigated the ability of hesperidin (C₂₈H₃₄O₁₅) to prevent apoptosis due to oxidative stress generated through UVB-induced ROS. Hesperidin significantly scavenged ROS generated by UVB radiation, attenuated the oxidation of cellular macromolecules, established mitochondrial membrane polarization, and prevented the release of cytochrome c into the cytosol. Hesperidin downregulated expression of caspase-9, caspase-3, and Bcl-2-associated X protein, and upregulated expression of B-cell lymphoma 2. Hesperidin absorbed wavelengths of light within the UVB range. In summary, hesperidin shielded human keratinocytes from UVB radiation-induced damage and apoptosis via its antioxidant and UVB absorption properties.

Antiaging effects of the mixture of Panax ginseng and Crataegus pinnatifida in human dermal fibroblasts and healthy human skin

BACKGROUND

Human skin undergoes distinct changes throughout the aging process, based on both intrinsic and extrinsic factors. In a process called photoaging, UVB irradiation leads to upregulation of matrix metalloproteinase-1, which then causes collagen degradation and premature aging. Mixtures of medicinal plants have traditionally been used as drugs in oriental medicine. Based on the previously reported antioxidant properties of Panax ginseng Meyer and Crataegus pinnatifida, we hypothesized that the mixture of P. ginseng Meyer and C. pinnatifida (GC) would have protective effects against skin aging.

METHODS

Anti-aging activity was examined both in human dermal fibroblasts under UVB irradiation by using Western blot analysis and in healthy human skin by examining noninvasive measurements.

RESULTS

In vitro studies showed that GC improved procollagen type I expression and diminished matrix metalloproteinase-1 secretion. Based on noninvasive measurements, skin roughness values, including total roughness (R1), maximum roughness (R2), smoothness depth and average roughness (R3), and global photodamage scores were improved by GC application. Moreover, GC ameliorated the high values of smoothness depth (R4), which means that GC reduced loss of skin moisture.

CONCLUSION

These results suggest that GC can prevent aging by inhibiting wrinkle formation and increasing moisture in the human skin.

Cell-based assay system for high-throughput screening of anti-photo-aging agents in fibroblast transfectants

The matricellular protein CCN1 is significantly elevated in acutely ultraviolet-irradiated human skin and negatively regulates collagen homeostasis by suppressing collagen synthesis and increasing collagen degradation. In this study, we established a stable cell line, termed CCN1-GFs, by transfection of the pAcGFP1-1-CCN1 promoter plasmid and examined its usefulness as a cell-based assay system for screening anti-aging ingredients. The promoter of the reporter plasmid pAcGFP1-1-CCN1 promoter was transfected into NIH3T3 cells using the Lipofectamine reagent. G418-resistant cells were selected and further cloned. To confirm whether AcGFP1-1-CCN1 promoter plasmid recombined in the NIH3T3 cells, the level of AcGFP1-1-CCN1 was measured by PCR analysis. To determine if NIH3T3 cells expressed the gene encoding green fluorescence protein in a CCN1 promoter-dependent manner, the reporter enzyme activities were assayed using a fluorimeter and flow cytometer. To determine if CCN1 inhibitor, which was selected through this system, exerted a direct effect on the downstream signal, mRNA expression of collagen1 and MMP1A was checked by using real-time PCR. UVB irradiation of CCN1-GFs resulted in increased CCN1 promoter activity. Treatment with retinoic acid, a CCN1 inhibitor, inhibited UV-induced CCN1 promoter activity. Subsequent use of this assay system to screen anti-aging ingredients revealed that CCN1-GFs treated with sclareol showed decreased levels of UVB-induced CCN1 expression. Sclareol attenuated UVB-induced photo-aging by an increase in collagen synthesis and decrease in MMP-1 activity.

Poly(I:C) induces expressions of MMP-1, -2, and -3 through various signaling pathways including IRF3 in human skin fibroblasts

BACKGROUND

Ultraviolet (UV) irradiation can result in premature skin aging (photoaging) which is characterized by decreased expression of collagen and increased expression of matrix metalloproteinases (MMPs). Double-stranded RNAs (dsRNAs) can be generated at various conditions including virally infected cells or UV-damaged skin cells. Recent studies have shown that a synthetic dsRNA, polyinosinic-polycytidylic acid (poly(I:C)), can reduce procollagen expression in human skin fibroblasts. However, little is known about the effect of poly(I:C) on the expression of MMPs in skin fibroblasts and its underlying mechanisms.

OBJECTIVE

We examined the effect of poly(I:C) on MMP-1, -2, and -3 expressions in human skin fibroblasts. Then, we further explored the underlying signaling pathways involved in the processes.

METHODS

Human skin fibroblasts were treated with poly(I:C) for the indicated times in the presence or the absence of various chemical inhibitors or small interfering RNAs (siRNAs) at the indicated concentrations. Protein and mRNA levels of various target molecules were examined by Western blotting and quantitative real-time PCR, respectively.

RESULTS

Poly(I:C) induced MMP-1, -2, and -3 expressions, which were dependent on TLR3. Poly(I:C) also induced activations of the mitogen-activated protein kinases (MAPKs), the nuclear factor-kappaB (NF-κB) and the interferon regulatory factor 3 (IRF3) pathways. By using specific inhibitors, we found that poly(I:C)-induced expressions of MMP-1, -2, and -3 were differentially regulated by these signaling pathways. In particular, we found that the inhibition of IRF3 signaling pathways attenuated poly(I:C)-induced expressions of all the three MMPs.

CONCLUSION

Our data show that the expressions of MMP-1, -2, and -3 are induced by poly(I:C) through various signaling pathways in human skin fibroblasts and suggest that TLR3 and/or IRF3 may be good targets for regulating the expressions of MMP-1, -2, and -3 induced by dsRNAs.

Increase of stratifin triggered by ultraviolet irradiation is possibly related to premature aging of human skin

Although ultraviolet (UV) rays cause premature aging of human skin, which is called photoaging, its detailed mechanisms are not known. Stratifin (SFN), a member of the 14-3-3 protein family, is secreted by keratinocytes on human skin, and has an effect on gene expression in other cells. In this study, the association of SFN with the mechanism of photoaging was investigated. The effect of UVB irradiation on SFN expression in epidermal keratinocytes was examined by in vitro and in vivo studies. In addition, the effects of SFN on epidermal keratinocytes and dermal fibroblasts were examined. SFN mRNA expression and protein levels increased significantly in UVB-irradiated keratinocytes. SFN significantly decreased filaggrin and serine palmitoyltransferase mRNA expression in epidermal keratinocytes and hyaluronan synthase 2 mRNA expression in dermal fibroblasts. In addition, it was reconfirmed that SFN induces the downregulation of collagen content through changes of COL-1, MMP-1 and MMP-2 mRNA expressions. Furthermore, the expression level of SFN mRNA was significantly higher in sun-exposed compared with that in sun-shielded skin. These results suggest that SFN affects the water-holding capacity, barrier function and dermal matrix components in photoaging skin. An increase of SFN triggered by UVB irradiation may be one of the causes of alterations observed in photoaging skin.

Autocrine Regulation of UVA-Induced IL-6 Production via Release of ATP and Activation of P2Y Receptors

Extracellular nucleotides, such as ATP, are released from cells in response to various stimuli and act as intercellular signaling molecules through activation of P2 receptors. Exposure to the ultraviolet radiation A (UVA) component of sunlight causes molecular and cellular damage, and in this study, we investigated the involvement of extracellular nucleotides and P2 receptors in the UVA-induced cellular response. Human keratinocyte-derived HaCaT cells were irradiated with a single dose of UVA (2.5 J/cm²), and ATP release and interleukin (IL)-6 production were measured. ATP was released from cells in response to UVA irradiation, and the release was blocked by pretreatment with inhibitors of gap junction hemichannels or P2X7 receptor antagonist. IL-6 production was increased after UVA irradiation, and this increase was inhibited by ecto-nucleotidase or by antagonists of P2Y11 or P2Y13 receptor. These results suggest that UVA-induced IL-6 production is mediated by release of ATP through hemichannels and P2X7 receptor, followed by activation of P2Y11 and P2Y13 receptors. Interestingly, P2Y11 and P2Y13 were associated with the same pattern of IL-6 production, though they trigger different intracellular signaling cascades: Ca²⁺-dependent and PI3K-dependent, respectively. Thus, IL-6 production in response to UVA-induced ATP release involves at least two distinct pathways, mediated by activation of P2Y11 and P2Y13 receptors.

Intraperitoneally administered biliverdin protects against UVB-induced skin photo-damage in hairless mice

Oxidative stress is shown to be responsible for ultraviolet B (UVB) irradiation-induced skin cancer and premature aging. Biliverdin (BVD), a product of heme oxygenase-1, has strong anti-oxidant and anti-inflammatory properties. In the present study, we investigated the effects of BVD on UVB-induced skin photo-damage in hairless mice. Mice were divided into three groups: control group, UVB group (only UVB irradiation) and BVD+UVB group (mice were intraperitoneally injected with BVD before each UVB irradiation). Intraperitoneal BVD injection resulted in a significant photoprotective effect by reducing morphological and histopathological changes to the skin. BVD also exhibited a significant antioxidant effect by increasing the superoxide dismutase (SOD) level and decreasing the thiobarbituric acid reactive substances (TBARS) level compared with the control group. In addition, BVD activated biliverdin reductase (BVR) expression and inhibited the UVB-induced increase of p38 mitogen-activated protein kinase phosphorylation (p-p38MAPK), MMP (matrix metalloproteinase)-1 and MMP-3 expression (p<0.05). It also significantly decreased the interleukin (IL)-6 level compared with the UVB group (p<0.05). In conclusion, these data suggest that the intraperitoneally administered BVD can prevent UVB irradiation-induced skin photo-damage in hairless mice and that this is likely mediated by its antioxidant and anti-inflammatory mechanisms and cell signal regulatory action.

Adipose-derived stem cells cooperate with fractional carbon dioxide laser in antagonizing photoaging: a potential role of Wnt and β-catenin signaling

BACKGROUND

It is well established that adipose-derived stem cells (ADSCs) produce and secrete cytokines/growth factors that antagonize UV-induced photoaging of skin. However, the exact molecular basis underlying the anti-photoaging effects exerted by ADSCs is not well understood, and whether ADSCs cooperate with fractional carbon dioxide (CO2) laser to facilitate photoaging skin healing process has not been explored. Here, we investigated the impacts of ADSCs on photoaging in a photoaging animal model, its associated mechanisms, and its functional cooperation with fractional CO2 laser in treatment of photoaging skin.

RESULTS

We showed that ADSCs improved dermal thickness and activated the proliferation of dermal fibroblast. We further demonstrated that the combined treatment of ADSCs and fractional CO2 laser, the latter which is often used to resurface skin and treat wrinkles, had more beneficial effects on the photoaging skin compared with each individual treatment. In our prepared HDF photoaging model, flow cytometry showed that, after adipose derived stem cells conditioned medium (ADSC-CM) co-cultured HDF photoaging model, the cell proliferation rate is higher than UVB irradiation induced HDF modeling (p < 0.05). Additionally, the expressions of β-catenin and Wnt3a, which were up-regulated after the transplantation of ADSCs alone or in combination with fractional CO2 laser treatment. And the expression of wnt3a and β-catenin has the positive correlation with photoaging related protein TGF-β2 and COLI. We also verified these protein expressions in tissue level. In addition, after injected SFRP2 into ADSC-CM co-cultured HDF photoaging model, wnt3a inhibitor, compared with un-intervened group, wnt3a, β-catenin protein level significantly decreased.

CONCLUSION

Both ADSCs and fractional CO2 laser improved photoaging skin at least partially via targeting dermal fibroblast activity which was increased in photoaging skin. The combinatorial use of ADSCs and fractional CO2 laser synergistically improved the healing process of photoaging skin. Thus, we provide a strong rationale for a combined use of ADSCs and fractional CO2 laser in treatment of photoaging skin in clinic in the future. Moreover, we provided evidence that the Wnt/β-catenin signaling pathway may contribute to the activation of dermal fibroblast by the transplantation of ADSCs in both vitro and vivo experiment.

Elevated cysteine-rich protein 61 (CCN1) promotes skin aging via upregulation of IL-1β in chronically sun-exposed human skin

Chronic exposure of human skin to solar ultraviolet (UV) irradiation causes premature skin aging, which is characterized by reduced type I collagen production and increased fragmentation of the dermal collagenous extracellular matrix. This imbalance of collagen homeostasis is mediated, in part, by elevated expression of the matricellular protein cysteine-rich protein 61 (CCN1), in dermal fibroblasts, the primary collagen producing cell type in human skin. Here, we report that the actions of CCN1 are mediated by induction of interleukin 1β (IL-1β). CCN1 and IL-1β are strikingly induced by acute UV irradiation, and constitutively elevated in sun-exposed prematurely aged human skin. Elevated CCN1 rapidly induces IL-1β, inhibits type I collagen production, and upregulates matrix metalloproteinase-1, which degrades collagen fibrils. Blockade of IL-1β actions by IL-1 receptor antagonist largely prevents the deleterious effects of CCN1 on collagen homeostasis. Furthermore, knockdown of CCN1 significantly reduces induction of IL-1β by UV irradiation, and thereby partially prevents collagen loss. These data demonstrate that elevated CCN1promotes inflammaging and collagen loss via induction of IL-1β and thereby contributes to the pathophysiology of premature aging in chronically sun-exposed human skin.

Quantification and visualization of cellular NAD(P)H in young and aged female facial skin with in vivo two-photon tomography

BACKGROUND

In vivo two-photon tomography is a novel noninvasive three-dimensional optical skin imaging technology with subcellular resolution which enables the sensitive detection of endogenous fluorophores. One of these fluorophores, NAD(P)H (a coenzyme which plays an important role in the release of free energy during glycolysis, and influences filaggrin and lipid synthesis), can be selectively detected in keratinocytes (granular cells) with two-photon tomography.

OBJECTIVES

To quantify NAD(P)H levels in subsurface human facial skin in vivo as a measure to determine if there are changes with age.

METHODS

A total of 80 healthy Asian females were enrolled in this study, aged 21-68 years. Measurements were performed on facial skin using in vivo two-photon tomography (DermaInspect/MPTflex™, JenLab GmbH, Jena, Germany). The laser beam scans a skin field of interest in pulses, focused at a depth to reach the granular layer. The near-infrared laser pulses excite the endogenous fluorophores NAD(P)H. Image processing was performed to obtain high-resolution autofluorescence images (optical biopsies) and to quantify the fluorescent grey scale to determine NAD(P)H levels. Additional skin surface measures taken were hydration (corneometer), elasticity (cutometer) and wrinkles (image capture and analysis).

RESULTS

Statistically significant changes in all measured parameters as a function of age were observed. Most importantly, the mean fluorescent grey scale values for NAD(P)H in the youngest group studied (women in their 20s) was 38.8 (SD ± 12.39), while that of the oldest group studied (women in their 60s) was 32.7 (SD ± 12.47). These NAD(P)H levels are statistically significantly different (P = 0.0078).

CONCLUSIONS

The level of NAD(P)H in the epidermis is significantly greater in younger vs. older skin in vivo. This likely reflects decreased production and/or increased degradation of NAD(P)H in older skin, possibly as a result of chronological ageing and environmental damage (e.g. photodamage). NAD(P)H levels in epidermal skin may be a useful biomarker of skin ageing in vivo. It is also likely that maintaining NAD(P)H production is a useful approach to maintaining good skin condition and caring for ageing skin.

The effect of cilostazol on the expression of matrix metalloproteinase-1 and type I procollagen in ultraviolet-irradiated human dermal fibroblasts

AIM

Cilostazol is a selective inhibitor of type III phosphodiesterase that inhibits platelet aggregation. Cilostazol is a useful vasodilator, antithrombotic, and cardiotonic agent. Ultraviolet B (UVB) irradiation increases the production of matrix metalloproteinase-1 (MMP-1) during skin photoaging. The UVB-induced increase of MMP-1 results in connective tissue damage, and the skin becomes wrinkled and aged. Here, we investigated the capacity of cilostazol to inhibit MMP-1 expression in UVB-irradiated human dermal fibroblasts.

MAIN METHODS

Cultured human dermal fibroblasts were irradiated with UVB, followed by the addition of cilostazol to the culture medium.

KEY FINDINGS

Post-treatment with cilostazol attenuated UVB-induced production of MMP-1 and prevented the reduction of type I procollagen. Cilostazol inhibited UVB irradiation-induced phosphorylation of the mitogen-activated protein kinase (MAPK) signaling molecules Jun-N-terminal kinase (JNK) and p38 kinase, as well as activator protein-1 (AP-1) in dermal fibroblasts.

SIGNIFICANCE

Overall, these results demonstrate that cilostazol regulates UVB-induced MMP-1 expression and type I procollagen synthesis by inhibiting MAPK signaling and AP-1 activity. Therefore, we suggest that cilostazol may be useful for the prevention and treatment of skin photodamage caused by UVB-irradiation.

Marine-derived nutrient improves epidermal and dermal structure and prolongs the life span of reconstructed human skin equivalents

INTRODUCTION

Imedeen™ is a cosmeceutical that provides nutrients to the skin. One of its active ingredients is the Marine Complex™ (MC).

AIM

The aim of this study was to evaluate whether MC affects skin morphogenesis differently in female and male human skin equivalents (HSEs).

METHODS

Human skin equivalents were established with cells obtained from female or male donors between 30 and 45 years of age and cultured for seven or 11 weeks in the presence or absence of MC. Using immunohistochemistry, we examined early differentiation by keratin 10 expression, (hyper)proliferation by keratin 17 and Ki67, and basement membrane composition by laminin 332 and collagen type VII. In addition, the expression of collagen type I and the secretion of pro-collagen I were measured.

RESULTS

Marine Complex strongly increased the number of Ki67-positive epidermal cells in female HSEs. In the dermis, MC significantly stimulated the amount of secreted pro-collagen I and increased the deposition of laminin 332 and collagen type VII. Furthermore, MC prolonged the viable phase of HSEs by slowing down its natural degradation. After 11 weeks of culturing, the MC-treated HSEs showed higher numbers of viable epidermal cell layers and a thicker dermal extracellular matrix compared with controls. In contrast, these effects were less pronounced in male HSEs.

CONCLUSION

The MC nutrient positively stimulated overall HSE tissue formation and prolonged the longevity of both female and male HSEs. The ability of MC to stimulate the deposition of basement membrane and dermal components can be used to combat 2 human skin aging in vivo.