Protect Skin Cells Research Articles

Sea cucumber-derived extract can protect skin cells from oxidative DNA damage and mitochondrial degradation, and promote wound healing

Our skin serves as the primary barrier against external environmental insults, the latter of which can cause oxidative stress within cells, while various bioactive peptides sourced from natural resources hold promise in protecting cells against such oxidative stress. In this study, we investigate the efficacy of a low molecular weight extract from the sea cucumber Apostichopus japonicus, denoted as Sample-P, in facilitating cell migration and wound healing under oxidative stress conditions in skin cells. The naturally derived compound is a highly complex mix of peptides exhibiting antioxidative properties, as highlighted through liquid chromatography-mass spectrometry peptide screening and an in vitro antioxidant assay. Our results demonstrate that Sample-P is capable of promoting cell migration while preventing severe stress responses such as visible through mTOR expression. To further identify the molecular pathways underpinning the overall protective mechanism of Sample-P, we have utilised a proteomics approach. Our data reveal that Sample-P regulates protein expression associated with ribosomal pathways, glycolysis/gluconeogenesis and protein processing in the endoplasmic reticulum (ER), which help in preserving DNA integrity and safeguarding cellular organelles, such as mitochondria and the ER, under oxidative stress conditions in skin cells. In summary, in the presence of H2O2, Sample-P exhibits antioxidative properties at both molecular and cellular levels, rendering it a promising candidate for topical skin treatment to wound healing and to address age-related skin conditions.

Shikonin protects skin cells against oxidative stress and cellular dysfunction induced by fine particulate matter.

Shikonin, an herbal naphthoquinone, demonstrates a broad spectrum of pharmacological properties. Owing to increasingly adverse environmental conditions, human skin is vulnerable to harmful influences from dust particles. This study explored the antioxidant capabilities of shikonin and its ability to protect human keratinocytes from oxidative stress induced by fine particulate matter (PM2.5). We found that shikonin at a concentration of 3 µM was nontoxic to human keratinocytes and effectively scavenged reactive oxygen species (ROS) while increasing the production of reduced glutathione (GSH). Furthermore, shikonin enhanced GSH level by upregulating glutamate-cysteine ligase catalytic subunit and glutathione synthetase mediated by nuclear factor-erythroid 2-related factor. Shikonin reduced ROS levels induced by PM2.5, leading to recovering PM2.5-impaired cellular biomolecules and cell viability. Shikonin restored the GSH level in PM2.5-exposed keratinocytes via enhancing the expression of GSH-synthesizing enzymes. Notably, buthionine sulphoximine, an inhibitor of GSH synthesis, diminished effect of shikonin against PM2.5-induced cell damage, confirming the role of GSH in shikonin-induced cytoprotection. Collectively, these findings indicated that shikonin could provide substantial cytoprotection against the adverse effects of PM2.5 through direct ROS scavenging and modulation of cellular antioxidant system.

ARE/Nrf2 Transcription System Involved in Carotenoid, Polyphenol, and Estradiol Protection from Rotenone-Induced Mitochondrial Oxidative Stress in Dermal Fibroblasts.

Skin aging is associated with the increased production of mitochondrial reactive oxygen species (mtROS) due to mitochondrial dysfunction, and various phytonutrients and estrogens have been shown to improve skin health. Thus, the aim of the current study was to examine damage to dermal fibroblasts by chemically induced mitochondrial dysfunction and to study the mechanism of the protective effects of carotenoids, polyphenols, and estradiol. Rotenone, a Complex I inhibitor, caused mitochondrial dysfunction in human dermal fibroblasts, substantially reducing respiration and ATP levels, followed by increased mitochondrial and cytosolic ROS, which resulted in apoptotic cell death, an increased number of senescent cells, increased matrix metalloproteinase-1 (MMP1) secretion, and decreased collagen secretion. Pre-treatment with carotenoid-rich tomato extracts, rosemary extract, and estradiol reversed these effects. These protective effects can be partially explained by a cooperative activation of antioxidant response element (ARE/Nrf2) transcriptional activity by the protective compounds and rotenone, which led to the upregulation of antioxidant proteins such as NQO1. To determine if ARE/Nrf2 activity is crucial for cell protection, we inhibited it using the Nrf2 inhibitors ML385 and ochratoxin A. This inhibition markedly reduced the protective effects of the test compounds by diminishing their effect to reduce cytosolic ROS. Our study results indicate that phytonutrients and estradiol protect skin cells from damage caused by mtROS, and thus may delay skin cell senescence and improve skin health.

Antioxidants for Skin Health.

Antioxidants play a pivotal role in maintaining skin health and integrity, combating the deleterious effects of oxidative stress induced by environmental aggressors such as UV ra-diation, pollution, and lifestyle factors. This paper reviews the contributions of key antioxidants, including Vitamin C, Vitamin E, Vitamin A, green tea extract, Coenzyme Q10, Resveratrol, Selenium, and Polyphenols, in skin health care. Vitamin C, known for its collagen synthesis promotion and photoprotection properties, alongside Vitamin E, a lipid-soluble antioxidant, syn-ergistically works to neutralize free radicals and repair damaged skin cells. Vitamin A, in the form of retinol, plays a critical role in skin cell regeneration and the maintenance of skin integ-rity. Green tea extract, rich in Polyphenols, offers anti-inflammatory and anticarcinogenic prop-erties, making it a potent ingredient for skin protection. Coenzyme Q10, a naturally occurring antioxidant in the body, aids in energy production for cell repair and regeneration, while Resveratrol, found in grapes and berries, provides anti-ageing benefits by enhancing skin's re-sistance to oxidative stress. Selenium, an essential mineral, contributes to the protection of skin cells from oxidative damage. The incorporation of these antioxidants in skincare products and dietary sources is discussed, highlighting the importance of a holistic approach in skincare re-gimes. The paper emphasizes the synergy between topical applications and dietary intake of antioxidants, advocating for a comprehensive strategy for promoting skin health and preventing age-related skin alterations. Method: For the review article, a variety of search engines and databases were used to identify relevant articles. Furthermore, for biomedical literature focusing on antioxidants and their ef-fects on skin health, PubMed was used. Moreover, to access a wide range of scholarly articles, including those related to dermatology and skincare, Google Scholar was used. Scopus provides comprehensive coverage of peer-reviewed literature across various scientific disciplines. Web of Science identifies high-impact articles and research on antioxidants in skincare. In addition, for accessing full-text articles on antioxidants and their applications in dermatology, Science Direct was used. The inclusion criteria for the review paper were as follows: only studies pub-lished in peer-reviewed journals were included to ensure the credibility and reliability of the information. Articles published in English were considered, to avoid language-related biases and ensure comprehension. Studies published within the last 10 years were included to provide the most current insights into antioxidant research in skincare. Articles must specifically focus on the role of antioxidants (Vitamin C, Vitamin E, Vitamin A, green tea extract, Coenzyme Q10, Resveratrol, Selenium, Polyphenols) in skin health care. Both experimental studies (in vivo and in vitro) and clinical trials were included to provide a comprehensive overview of the antioxidant effects. Full-text articles were included to allow for thorough data extraction and analysis. The exclusion criteria for the review paper were as follows: Publications that were not peer-re-viewed, such as editorials, opinion pieces, and non-scholarly articles, were excluded. Articles published in languages other than English were excluded due to potential translation challenges and to maintain consistency. Studies that did not focus on the specified antioxidants or their impact on skin health were excluded. Duplicate publications were excluded to avoid redundancy in the review. Articles with insufficient or incomplete data were excluded to ensure the quality and reliability of the review findings.

Combined use of versatile peroxidase and aryl alcohol oxidase of Pleurotus eryngii to decolorize melanin on the skin

Melanin plays an important role in protecting skin cells from harmful UV radiation, but its uneven pigmentation in the skin sometimes demands cosmetic resolution. As a safe and effective way of evening the skin tone, enzymatic decolorization of melanin at the stratum corneum has been proposed. In this regard, the use of lignin peroxidase, in the presence of hydrogen peroxide and veratryl alcohol, an electron mediator, has been explored. Here, we first show that versatile peroxidase (VP) and aryl alcohol oxidase (AAO) purified from the Pleurotus eryngii liquid culture can be used to decolorize melanin without exogenous hydrogen peroxide. This resembles the oxidative degradation pathway of lignin in nature; AAO generates hydrogen peroxide from veratryl alcohol, and VP utilizes generated hydrogen peroxide while using veratryl alcohol as a mediator. We further explored the use of POX_Pe, the crude peroxidase preparation of the Pleurotus eryngii liquid culture, for melanin decolorization because of its better stability. Using POX_Pe and veratryl alcohol, over 60 % of melanin decolorization was obtained in 1 h in the absence of exogenous hydrogen peroxide addition. Furthermore, POX_Pe could decolorize melanin in a 3D human pigmented epidermis model, demonstrating its possible applications in cosmetics.

The protection role of human growth hormone on skin cells following ultraviolet B exposure

BackgroundUltraviolet-B (UVB) radiation is the leading environmental cause of skin damage and photoaging. The epidermis and dermis layers of the skin mainly absorb UVB. UVB stimulates apoptosis, cell cycle arrest, generation of reactive oxygen species, and degradation of collagen and elastin fibers. ObjectiveThis study investigated the potential of human growth hormone (hGH) in protecting the skin fibroblasts and keratinocytes (HFFF-2 and HaCaT cell lines) from UVB-induced damage. MethodsThe MTT assay was performed to evaluate UVB-induced mitochondrial damage via assessing the mitochondrial dehydrogenase activity, and flow cytometry was carried out to investigate the effects of UVB and hGH on the cell cycle and apoptosis of UVB-irradiated cells. In addition, the fold change mRNA expression levels of Type I collagen and elastin in HFFF-2 cells were evaluated using the qRT-PCR method following UVB exposure. ResultsWe observed that treatment of cells with hGH before UVB exposure inhibited UVB-induced loss of mitochondrial dehydrogenase activity, apoptosis, and sub-G1 population formation in both cell lines. We also found that hGH-treated HFFF-2 cells showed up-regulated mRNA expression of Type I collagen, elastin, and IGF-1 in response to UVB irradiation. ConclusionThese findings suggest hGH as a potential anti-UVB compound that can protect skin cells from UVB-induced damage. Our findings merit further investigation and can be used to better understand the role of hGH in skin photoaging.

Stem-Cell-Regenerative and Protective Effects of Squid (Symplectoteuthis oualaniensis) Skin Collagen Peptides against H2O2-Induced Fibroblast Injury.

Recently, there has been a growing interest in collagen peptides derived from marine sources for their notable ability to protect skin cells against apoptosis induced by oxidants. Therefore, the current study aimed to investigate the fundamental properties of collagen peptides, including their physicochemical, thermal, structural, stem-cell-regenerative, and skin-cell-protective effects, in comparison to commercial collagen peptides. The acid-soluble (ASC) and pepsin-soluble (PSC) collagens exhibited three distinct bands on SDS-PAGE, namely α (α1 and α2), β, and γ chains, confirming a type I pattern. The thermal profiles obtained from TG and DSC analyses confirmed the denaturation of PSC and ASC at temperatures ranging from 51.94 to 56.4 °C and from 52.07 to 56.53 °C, respectively. The purified collagen peptides were analyzed using SDS-PAGE and MALDI-TOF mass spectrometry, revealing a mass range of 900-15,000 Da. Furthermore, the de novo peptide sequence analysis confirmed the presence of the Gly-X-Y repeating sequence in collagen peptides. Collagen peptide treatments significantly enhanced HFF-1 cell proliferation and migration compared to the control group. ELISA results confirmed the potential interactions between collagen peptides and HFF-1 cells through α2β1, α10β1, and α11β1 integrin receptors. Notably, collagen peptide treatment effectively restored the proliferation of HFF-1 cells damaged by H2O2. Consequently, the advantageous characteristics of squid skin collagen peptides highlight their promising role in regenerative medicine.

Protective Effects of the Postbiotic Levilactobacillus brevis BK3 against H2O2-Induced Oxidative Damage in Skin Cells.

Postbiotics have various functional effects, such as antioxidant, anti-inflammatory, and anti-obesity. Levilactobacillus brevis BK3, the subject of this study, was derived from lactic acid bacteria isolated from Kimchi, a traditional Korean fermented food. The antioxidant activity of BK3 was confirmed through the measurements of 2,2-diphenyl-1-picryl-hydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and total antioxidant capacity (TAC). The wrinkle improvement effect was validated by assessing elastase inhibitory activity and collagenase inhibitory activity. The intracellular activity was confirmed using human keratinocytes (HaCaT) and human fibroblasts (HFF-1). BK3 protects skin cells from oxidative stress induced by H2O2 and reduces intracellular reactive oxygen species (ROS) production. In addition, the expressions of the antioxidant genes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were upregulated. Meanwhile, matrix metalloproteinase-1 (MMP-1) and collagen type I alpha 1 (COL1A1), involved in collagen degradation and synthesis, were significantly regulated. These results suggest the possibility of utilizing BK3 as a functional ingredient with antioxidant and wrinkle-improving effects.

Protective Effects of Pear Extract on Skin from In Vitro and In Vivo UVA-Induced Damage.

The ancient Chinese medical book "Compendium of Materia Medica" records that pears can relieve symptoms of respiratory-related diseases. Previous research has shown that pear Pyrus Pyrifolia (Burm.f.) Nakai has antioxidant and anti-inflammatory properties. However, the anti-inflammatory, antioxidant, and anti-photoaging protective effects of Pyrus pyrifolia (Burm.f.) Nakai seed components have not been studied. Ultraviolet light (UV) causes skin inflammation, damages the skin barrier, and is an important cause of skin photoaging. Therefore, UV light with a wavelength of 365 nm was used to irradiate HaCaT and mice. Western blot, real-time quantitative polymerase chain reaction, and fluorescence imaging system were used to explore its anti-UVA mechanism. Dialysis membrane and nuclear magnetic resonance were used for the chemical constituent analysis of pear seed water extract (PSWE). We found that PSWE can significantly reduce UVA-induced skin cell death and mitogen-activated protein kinase phosphorylation and can inhibit the mRNA expression of UVA-induced cytokines (including IL-1β, IL-6, and TNF-α). In addition, PSWE can also reduce the generation of oxidative stress within skin cells. In vivo experimental studies found that PSWE pretreatment effectively reduced transepidermal water loss, inflammation, redness, and dryness in hairless mice. The molecular weight of the active part of pear water extract is approximately 384. Based on the above results, we first found that pear seeds can effectively inhibit oxidative stress and damage caused by UVA. It is a natural extract with antioxidant properties and anti-aging activity that protects skin cells and strengthens the skin barrier.

Anti-Ferroptotic Effect of Cannabidiol in Human Skin Keratinocytes Characterized by Data-Independent Acquisition-Based Proteomics.

Skin cells are susceptible to oxidative stress and various types of cell death, including an iron-dependent form known as ferroptosis. Cannabidiol (CBD) can protect skin cells against oxidative stress, but whether this is attributed to the inhibition of ferroptosis is unknown. Herein, we evaluated the anti-ferroptotic effect of CBD in human keratinocytes using biochemical assays (radical scavenging and iron chelating) and cell-based models (for lipid peroxidation and intracellular iron). CBD's anti-ferroptotic effect was further characterized by proteomic analysis. This study identifies anti-ferroptosis as a mechanism of CBD's skin protective effects.

Plant-Derived Extracts Plus Vitamin E and/or Aloe Vera Protect Against Intrinsic/Extrinsic Stressor in Human Skin: In Vitro and Clinical Evidence.

Humans are exposed to physical, biological, chemical, and psychological stressor throughout their life span. In recent years many medicinal plants have been shown to induce stress adapting and protective functions. Plant-derived extracts and vitamin E exhibit stress protection or resistance by normalizing cellular homeostasis and enhancing resistance to toxic stimuli to overcome cellular damage. Here we report the evaluation of a topical preparation (product test materials; PTM) containing an ingredient blend of Rhodiola Rosea, Eleutherococcus Senticosus (Siberian Ginseng), Rhaponticum Carthamoides, Inonotus Obliqus, and Slegainella Lepidophylla as the base formula and tested the addition of Lespedeza Capitata (leaf/stem) extract plus vitamin E and/or Aloe Vera to determine the induced protective functions in human skin when challenged with intrinsic and extrinsic stressors. The base topical preparation plus Lespedeza Capitata extract plus vitamin E or the base topical preparation plus vitamin E and Aloe Vera were assayed in vitro on (a) intrinsically stressed excised abdominoplasty skin, (b) full thickness (FT) skin equivalent models post-treated with a combination of ultra-violet (UV) B light (250 mJ/cm2) and diesel particular matter (DPM) (75 µg/mL) skin, for their effect on antioxidant, inflammation, and stress biomarker geners. Additionally, the bioadaptive activity of the PTMs was confirmed in providing resilience and protection against UV-induced erythema. For example, in a clinical study, daily topical application of the PTMs on the buttocks of 20 woman (18-78 years old), average age of 51.1 years, median body mass index (BMI) of 26.5 for 8 weeks followed by 2 minimal erythema dose (MED) of UVB exposure was accessed 24 hours after irradiation. Statistical analysis was performed by t-test and ANOVA, repectively. Pretreatment with the topical PTMs on intrsinically stressed skin significantly reduced the expression of the stress gene biomarkers, p53, pro-inflammatory cytokines Interleukin-1β (IL-1β) and Tumor Necrosis Factor-α (TNFα) and the pro-apoptotic BCL2 associated X, apoptosis regulator (BAX) values compared to controls. Topical application of the PTMs on Full Thickness (FT) human skin treated with UVB light and DPM significantly enhanced the stress response by activating heat shock transcription factor 4 (HSF4) and heat shock protein family B (small) member 1 (HSPB1) gene levels belonging to the heat shock protein (HSP) family by significantly increasing the expression of heme oxygenase 1 (HMOX1). At the same time, significantly reducing IL-1β levels were observed plus protection of skin cells from toxicity ocurred by significantly increasing the expression of B-cell lymphoma 2 (BCL2) (anti-apoptotic gene). In the clinical study, daily topical applications of the PTMs for 8 weeks followed by 2MED of UVB irradiation with clinical assessment 24 hours later revealed a significantly reduced intensity of erythema when compared to the buttock region treated with UVB alone. The PTMs containing adaptogen ingredients may confer stress resistance and induce stress protective responses against intrinsic as well as extrinsic stressors as demonstrated by the obtained in vitro and clinical evidence.

Protective role of melatonin in ultraviolet radiation- induced oxidative stress in human skin photoaging

The ultraviolet radiation of the sun that reaches the earth is made up of ultraviolet A (95%) and ultraviolet B (5%). Exposure to ultraviolet radiation (UVR) is the main factor in photoaging. Chronic exposure to sunlight acts as an environmental stressor, leading to oxidative damage or stress. Oxidative damage stimulates the accumulation of free radicals, such as reactive oxygen species (ROS) or reactive nitrogen species (RNS) that are responsible for premature skin aging. Photoaged skin is characterized externally by irregular pigmentation, wrinkles, and reduced skin elasticity, and internally by the breakdown of dermal collagen and elastin. Free radicals can be scavenged and the skin can be protected from further oxidative damage by antioxidants. Melatonin is a hormone produced mainly by the pineal gland, as well as many other organs, including the skin. One of the functions of melatonin is exerted by the antioxidative melatoninergic system to prevent ultraviolet (UV)-induced skin photoaging. The aim of this review was to study the protective effect of melatonin on skin photoaging resulting from UVR exposure. The references were tracked using various databases, such as Google Scholar and PubMed with regard to publications in English for the last 5 years (2019-2023). Melatonin inhibits UVR-induced aging in multiple ways, such as protecting skin cells, binding free radicals, accelerating the activity of antioxidant enzymes, preventing increased mitochondrial membrane permeability, and assisting electron transport efficiency in the mitochondrial respiratory chain. Exogenous application of melatonin is usually by the oral route, but for localized effects on the skin, topical administration is recommended, with consideration of preparations with a better half-life and bioavailability. Understanding the protective antioxidant function of melatonin in UV-induced skin photoaging helps to optimize its application. The protective properties of melatonin against UVR-oxidative stress-induced photoaging will be further explored in this review.

Bombyx Mori as a Potential Sunscreen to Prevent Photoaging

Excessive exposure to solar UV radiation is a major cause of skin photoaging, which is characterized by premature wrinkling, hyperpigmentation, and loss of skin elasticity. Traditional synthetic sunscreens are effective, but their potential side effects have led to a search for natural alternatives. Bombyx mori has attracted attention for its rich composition of bioactive compounds, such as silk proteins, sericin and fibroin, which have antioxidant and anti-inflammatory properties. These components are believed to contribute to the protection of skin cells against oxidative stress and inflammation from UV rays, thereby slowing down the aging process. This review systematically examines recent studies that have investigated the photoprotective effects of Bombyx mori-derived extracts, silk proteins, and other related substances. Findings suggest that these natural agents have the potential to reduce UV damage by enhancing skin defense mechanisms, promoting collagen synthesis, and reducing matrix metalloproteinase expression. In addition, the hypoallergenic properties of Bombyx mori compounds make them suitable for individuals with sensitive skin, thereby expanding their application in the skin care industry. However, while promising, research on Bombyx mori as a sunscreen agent is still in its early stages. Further studies are needed to elucidate the mechanisms underlying their photoprotective effects, assess their long-term safety, and optimize their formulations for effective delivery to the skin. This literature review contributes to a comprehensive understanding of the potential of Bombyx mori as an alternative to natural sunscreens and highlights the need for further research in harnessing its benefits to fight photoaging and maintain healthy skin.

Lycium barbarum polysaccharide inhibits blue-light-induced skin oxidative damage with the involvement of mitophagy.

Although blue light can damage the skin to a certain extent, the pathogenesis of its damage remains still unclear. The available evidence suggests that oxidative stress may be the main cause of its damage. Lycium barbarum polysaccharide (LBP) has antioxidative effects in a variety of cells. In this paper, we investigated the protective role of LBP and its mechanism of action related to mitophagy in blue-light-damaged skin cells. The findings indicated that in HaCaT cells and mouse skin, LBP pretreatment was effective in reducing blue-light-induced apoptosis and ameliorating the elevated level of cellular autophagy/mitophagy caused by excessive blue light exposure. The markers reactive oxygen species (ROS), superoxide dismutase (SOD), and malondialdehyde (MDA) were used to assess oxidative stress. LBP could effectively inhibit blue-light-induced oxidative stress. It was also found that blue light exposure caused mitochondrial dysfunction in HaCaT cells, including increased intracellular calcium ion levels and decreased mitochondrial membrane potential. LBP pretreatment significantly relieved mitochondrial dysfunction in HaCaT cells. These findings imply that LBP pretreatment protects skin cells from damage induced by blue light irradiation and that mitophagy may be a significant factor in skin photodamage.

PEMANFAATAN LIMBAH KULIT BAWANG PUTIH (Allium sativum L.) SEBAGAI BAHAN AKTIF PEMBUATAN SABUN CAIR

Utilization of household waste in Indonesia is still very rarely done, one of which is the use of garlic skin waste. From research by Allemann & Baumann in 2008, garlic skin is rich in antioxidant compounds so it can protect skin cells from free radical damage if used as a skincare product, one of which is liquid bath soap for the body. This research aims to formulate garlic skin extract as liquid soap. The concentration used is 10%. The liquid soap formulation used was 17 g of SLS, 3 g of NaCl, 9 g of Cocamidopropyl Betaine, 9 g of Glycerin, Fragrances, and Dyes to taste. Garlic skin extract liquid soap is evaluated for its physical quality consisting of organoleptic test results in the form of liquid, gum-scented and red-colored, pH test of 8.2, height test and foam stability of 79 mm, moisture content test of 51.12%, specific gravity test of 1.012 g/ml, and irritation test declared non-irritating. The results showed that garlic skin extract liquid soap with a concentration of 10 % had a physical quality that complied with their requirements. This research concludes that garlic skin extracts liquid soap meets the requirements of the physical quality test and safe for the skin because it does not cause irritation to the skin when used.

Sustained pigmentation causes DNA damage and invokes translesion polymerase Polκ for repair in melanocytes.

Melanin protects skin cells from ultraviolet radiation-induced DNA damage. However, intermediates of eumelanin are highly reactive quinones that are potentially genotoxic. In this study, we systematically investigate the effect of sustained elevation of melanogenesis and map the consequent cellular repair response of melanocytes. Pigmentation increases γH2AX foci, DNA abasic sites, causes replication stress and invokes translesion polymerase Polκ in primary human melanocytes, as well as mouse melanoma cells. Confirming the causal link, CRISPR-based genetic ablation of tyrosinase results in depigmented cells with low Polκ levels. During pigmentation, Polκ activates replication stress response and keeps a check on uncontrolled proliferation of cells harboring melanin-damaged DNA. The mutational landscape observed in human melanoma could in part explain the error-prone bypass of DNA lesions by Polκ, whose absence would lead to genome instability. Thereby, translesion polymerase Polκ is a critical response of pigmenting melanocytes to combat melanin-induced DNA alterations. Our study illuminates the dark side of melanin and identifies (eu)melanogenesis as a key missing link between tanning response and mutagenesis, mediated via the necessary evil translesion polymerase, Polκ.

Topically applied fullerenols protect against radiation dermatitis by scavenging reactive oxygen species

Adverse skin reactions caused by ionizing radiation are collectively called radiation dermatitis (RD), and the use of nanomedicine is an attractive approach to this condition. Therefore, we designed and large-scale synthesized fullerenols that showed free radical scavenging ability in vitro. Next, we pretreated X-ray-exposed cells with fullerenols. The results showed that pretreatment with fullerenols significantly scavenged intracellular reactive oxygen species (ROS) produced and enhanced the antioxidant capacity, protecting skin cells from X-ray-induced DNA damage and apoptosis. Moreover, we induced RD in mice by applying 30 Gy of X-ray irradiation, followed by treatment with fullerenols. We found that after treatment, the RD scores dropped, and the histological results systematically demonstrated that topically applied fullerenols could reduce radiation-induced skin epidermal thickening, collagen deposition and skin appendage damage and promote hair regeneration after 35 days. Compared with Trolamine cream, a typical RD drug, fullerenols showed superior radiation protection. Overall, the in vitro and in vivo experiments proved that fullerenols agents against RD.

Anti-Melanogenesis and Anti-Photoaging Effects of the Sulfated Polysaccharides Isolated from the Brown Seaweed Padina boryana.

Sulfated polysaccharides isolated from seaweeds are thought of as ideal ingredients in the pharmaceutical, nutraceutical, and cosmetics industries. Our previous study isolated and characterized sulfated polysaccharides from Padina boryana. The sulfated polysaccharides of Padina boryana (PBP) were extracted, and the antioxidant activity of PBP was evaluated. The results indicate that PBP possesses antioxidant effects and potential in the cosmetic industry. To further investigate the potential of PBP in cosmetics, the photoprotective and anti-melanogenesis effects of PBP were evaluated. The anti-melanogenesis test results display that PBP reduced the melanin content in the murine melanoma cells stimulated by alpha melanocyte-stimulating hormone from 203.7% to 183.64%, 144.63%, and 127.57% at concentrations of 25 μg/mL, 50 μg/mL, and 100 μg/mL, respectively. The anti-photodamage test results showed that PBP significantly protected skin cells against UVB-stimulated photodamage. PBP suppressed human epidermal keratinocyte (HaCaT cell) death by inhibiting apoptosis and reducing the level of intracellular reactive oxygen species. The intracellular reactive oxygen species level of HaCaT cells irradiated by UVB was reduced from 192.67% to 181.22%, 170.25%, and 160.48% by 25 μg/mL, 50 μg/mL, and 100 μg/mL PBP, respectively. In addition, PBP remarkably reduced UVB-induced human dermal fibroblast damage by suppressing oxidative damage, inhibiting collagen degradation, and attenuating inflammatory responses. These results indicate that PBP possesses photoprotective and anti-melanogenesis activities and suggest that PBP is a potential ingredient in the cosmetic industry.

Proteins from toad’s parotoid macroglands: do they play a role in gland functioning and chemical defence?

BackgroundParotoid gland secretion of bufonid toads is a rich source of toxic molecules that are used against predators, parasites and pathogens. Bufadienolides and biogenic amines are the principal compounds responsible for toxicity of parotoid secretion. Many toxicological and pharmacological analyses of parotoid secretions have been performed, but little is known about the processes related to poison production and secretion. Therefore, our aim was to investigate protein content in parotoids of the common toad, Bufo bufo, to understand the processes that regulate synthesis and excretion of toxins as well as functioning of parotoid macroglands.ResultsApplying a proteomic approach we identified 162 proteins in the extract from toad’s parotoids that were classified into 11 categories of biological functions. One-third (34.6%) of the identified molecules, including acyl-CoA-binding protein, actin, catalase, calmodulin, and enolases, were involved in cell metabolism. We found many proteins related to cell division and cell cycle regulation (12.0%; e.g. histone and tubulin), cell structure maintenance (8.4%; e.g. thymosin beta-4, tubulin), intra- and extracellular transport (8.4%), cell aging and apoptosis (7.3%; e.g. catalase and pyruvate kinase) as well as immune (7.0%; e.g. interleukin-24 and UV excision repair protein) and stress (6.3%; including heat shock proteins, peroxiredoxin-6 and superoxide dismutase) response. We also identified two proteins, phosphomevalonate kinase and isopentenyl-diphosphate delta-isomerase 1, that are involved in synthesis of cholesterol which is a precursor for bufadienolides biosynthesis. STRING protein-protein interaction network predicted for identified proteins showed that most proteins are related to metabolic processes, particularly glycolysis, stress response and DNA repair and replication. The results of GO enrichment and KEGG analyses are also consistent with these findings.ConclusionThis finding indicates that cholesterol may be synthesized in parotoids, and not only in the liver from which is then transferred through the bloodstream to the parotoid macroglands. Presence of proteins that regulate cell cycle, cell division, aging and apoptosis may indicate a high epithelial cell turnover in parotoids. Proteins protecting skin cells from DNA damage may help to minimize the harmful effects of UV radiation. Thus, our work extends our knowledge with new and important functions of parotoids, major glands involved in the bufonid chemical defence.

Ceratonia siliqua L. Pod Extract: From Phytochemical Characterization to Liposomal Formulation and Evaluation of Behaviour in Cells.

The formulation of plant extracts in phospholipid vesicles is a promising strategy to exploit their biological properties while solving problems related to poor solubility in water, high instability, and low skin permeation and retention time. In this study, Ceratonia siliqua ripe pods were used for the preparation of a hydro-ethanolic extract, which showed antioxidant properties owing to the presence of biologically active compounds identified by liquid chromatography-mass spectrometry (e.g., hydroxybenzoic acid and flavonoid derivatives). To improve the applicability of the extract in therapy, a topical formulation based on liposomes was explored. The vesicles were characterized by small size (around 100 nm), negative charge (-13 mV), and high entrapment efficiency (>90%). Furthermore, they displayed both spherical and elongated shapes, with oligolamellar structure. Their biocompatibility was demonstrated in cells, including erythrocytes and representative skin cell lines. The antioxidant activity of the extract was proved by the scavenging of free radicals, the reduction of ferric ions, and the protection of skin cells from oxidative damage.